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The Ecological Impacts of Climate Change

Eco-Aware Climate Consultants Integrated Report

Date: Wednesday April 2nd, 2014 Biology 4A03

Adam Armstrong 1046412 Alanna Smolarz 1132029

Emily Hague 1052572 Michael Hafezi 1067616

Samantha Stead 1057188 Shelby Hofstetter 1157695

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Acknowledgments

Dear Reader,

The Eco-Aware Climate Consultants would like to take this opportunity to thank Dr. Lovaye

Kajiura for her mentorship throughout the many steps taken to create this report. Through her

guidance this report was able to flourish into what it is today, and become an incredible capstone

to many of our groups final year at McMaster University.

We would further like to thank Emily Stacy our teaching assistant for her guidance throughout

the semester. The time that was taken in order to answer our many questions is greatly

appreciated.

Continuing we would also like to take this opportunity to thank Dr. Graham Scott for allowing

us the time to sit down with our group for an interview. Your insight into species plasticity was

greatly appreciated.

Furthermore we would like to thank our colleagues in Biology 4A03/ 2014 for allowing us to

share in your ideas and learning. Together we have all worked to create meshing reports that

truly prove how interconnected our world is.

Lastly we would like to thank our families and friends for their continued support throughout

these past couple of months. Whether it was helping us practice for presentations, editing our

work, or just being there for support your efforts did not go unnoticed.

Sincerely Thank You,

The Eco-Aware Climate Consultants

Adam Armstrong

Alanna Smolarz

Emily Hague

Michael Hafezi

Sam Stead

Shelby Hofstetter

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Table of Contents Page #

List of Figures and Tables 6

1. Introduction 8

1.1 Climate Change 9

2. Synthesis 11

2.1 Question 1: Response and Prediction of Changes 13

2.1.1 Introduction 13

2.1.2 Terrestrial Environments 13

2.1.2.1 Range Shifts 13

2.1.2.2 Phenotypic Plasticity and Phenology 14

2.1.2.3 Predicting Changes 15

2.1.2.4 Species Management 17

2.1.2.5 Future Directions 18

2.1.3 Marine Environments 18

2.1.3.1 Changing Phenology 18

2.1.3.2 Temperature Effects 19

2.1.3.3 Range Shifts 20

2.1.3.4 Predicting Changes 21

2.1.3.5 Future Directions 21

2.2 Question 2: Climate Change-Induced Natural Disasters 24

2.2.1 Effects of Climate Change on Occurrence of Natural Disasters 24

2.2.2 Disturbances, Intermediate Disturbance Hypothesis and Resilience 24

2.2.3 Introduction to Climate Change-Induced Natural Disasters 26

2.2.3.1 Floods 26

2.2.3.2 Droughts 27

2.2.3.3 Forest Fires 28

2.2.3.4 Landslides 29

2.2.3.5 Hurricanes 30

2.2.4 Conclusions 31

2.2.5 Future Directions 32

2.3 Question 3: Ecological Based Human Measures 34

2.3.1 Introduction 34

2.3.2 Management Options for Terrestrial Ecosystems Affected by Wildfires 34

2.3.3 Restoration Strategies for Wetland Habitats Affected by Storm Surges 37

2.3.4 Conservation Strategies for Marine Environments affected by Ocean Warming 40

2.3.5 Future Directions 43

3. Integration 45

3.1 Agricultural Implications of a Warming Climate 47

3.1.1 Impacts of Agriculture on Global Warming 47

3.1.2 Impacts of Global Warming on Agriculture 48

3.2 Impacts of Climate Change on Human Health 52

3.2.1 Disease Vectors 52

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3.2.2 Heat Waves 53

3.2.3 Natural Disasters 54

3.2.3.1 Floods 54

3.2.3.2 Hurricanes 55

3.3 Effect of Floods on the Spread of Contaminants 57

3.3.1 Future Directions 58

3.4 The Relationship between Climate Change and Poverty 60

3.4.1 Increased Carbon Emissions 60

3.4.2 Unsustainable Livelihood and Climate Warming 61

3.4.3 Unsustainable Livelihoods Increases Risks 62

3.4.4 Increased Vulnerability to Natural Disasters 63

3.4.5 Future Directions 63

3.5 Climate Change and Drought Resistant Crops 66

3.5.1 Climate Change-Mediated Crop Yield Loss and Future Food Security 66

3.5.2 Possible Climate Change Outcomes Due to Human Activity 66

3.5.3 Global Food Security and Areas of Need 67

3.5.4 Improving Drought-Tolerance by Breeding and Genetic Modification 68

3.5.5 Potential Risks of Genetic Modification 69

3.5.6 Present Genetically Modified Drought-Tolerance and Future Interests 69

3.5.7 Conclusions and Future Directs 70

3.6 Sustainable Solutions to Anthropogenic Changes and Climate Change 73

3.6.1 Introduction 73

3.6.2 Adaptive Water Management to Mitigate Direct Climate Change Effects 73

3.6.3 Strategies to Manage Indirect Effects of Climate Change 75

3.6.3.1 Clear Cutting in Relation to Wildfires and Landslides 76

3.6.3.1.1 Wildfires Caused by Clear cutting, Enhanced by Climate Change 76

3.6.3.1.2 Landslides Caused by Clear cutting, Enhanced by Climate Change 78

3.6.3.2 Sustainability of Costal Protection and Alternate Strategies 79

3.6.3.3 Effects of Hydroelectric Dams on the Climate and Earthquakes 80

3.6.4 Future Directions 82

4. Conclusions 84

4.1 Concluding Remarks 85

5. Reflections 87

5.1 Agricultural Implications of a Warming Climate 88

5.2 Insights Gained 88

5.3 Learning Experiences 89

5.3.1 Within Groups 89

5.3.2 Between Groups 89

5.4 Challenges Faced and Resolutions 90

5.5 Developed Skills 91

5.6 Future Goals 92

5.7 Final Remarks 92

6. References 93

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7. Appendix 116 Appendix A 117

Appendix B 124

Appendix C 128

Appendix D 137

Appendix E 158

Appendix F 165

Appendix G 167

Appendix H 187

Appendix I 194

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List of Figures and Tables

Figure 1. Fluctuations of temperature and carbon dioxide levels in Antarctic ice cores

(Whittingstall).

Figure 2. Global temperature anomalies since 1870 (Dahlman, 2009).

Figure 3. This diagram was used to represent the vulnerability of a species or ecosystems based

on its exposure to climate change (x- axis) as well as its sensitivity and its ability to adapt (y-

axis) (Dawson et al. 2011).

Figure 4. Graphical representation of the Intermediate Disturbance Hypothesis showing species

richness for different levels of disturbance (Wilkinson, 1999).

Figure 5. Mean annual relative growth rates by drought class (1, no drought 4, severe drought) for pine, oak and mesophytic species groups (Klos et al. 2009).

Figure 6. Graphical summary of the correlation between temperature increase and area burned

(Gillett et al. 2004).

Figure 7. Inforgraphics provided for public distribution depicting the current trends of wildfires

and climate change in western United States (Union of Concerned Scientists, 2013)

Figure 8. Intensity of hurricane according to the Saffir- Simpson scale from categories 1-5. It is

seen that for both number of intense hurricanes and percent of intense hurricanes, the number of

category 4 and 5 hurricanes is increasing. Category 1,2 and 3 hurricanes appear to be

decreasing (Webster et al. 2005).

Figure 9. Visual representation of the differences between conventional coastal engineering

(left) and ecosystem-based coastal defence (right). Blue arrows indicate an increase in intensity

of storm waves and storm surges. The green arrows represent the wetland sedimentation

stimulated by storm waves (Temmerman et al. 2013).

Figure 10. Map showing the global need for coastal flood protection and large-scale samples.

Potential application of ecosystem-based defence is also shown: dark green has the greatest

potential, pale green has moderate potential, orange represents cities with minimal potential,

blue are cities existing directly on coasts with the least potential (Temmerman et al. 2013).

Figure 11. The distributions of peak surge heights along four profiles across mangrove zones of

varying widths (coloured lines). The black solid line represents surge amplitudes along a profile

without mangrove effects (Zhang et al. 2012).

Figure 12a. Relationship between rice spikelet sterility and the mean maximum temperature

during the 20 days before and after anthesis (Taro et al. 2006).

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Figure 12b. Relationship between maize yield and mean diurnal temperature in summer (Taro et

al. 2006).

Figure 13. The projected levels of energy-related carbon dioxide emissions from both developed

(OECD) and developing (Non-OECD) nations (U.S. Energy Information Administration, 2013).

Figure 14. The different components of adaptive management represented in an extended PSIR

(Pressure-State-Impact-Response) framework (Pahl-Wostl, 2007).

Figure 15. Susceptibility of forests to wildfires as a result of damages caused by clear cutting

(Franklin & Forman, 1987).

Figure 16. Fire risk compared to time since landscape was first clear-cut. The landscape was

differentiated between ignition points and forest edges (Lindenmayer et al. 2009).

Figure 17. This map constructed using Google Maps but provided by International Rivers

displays the locations worldwide of suspected reservoir-induced seismicity (International Rivers,

2014).

Table 1. Cumulative area bound, forested area and percent area burned for ecozones in Canada

between 1980 and 1999 (Flannigan et al. 2005).

Table 2. Summary of main findings on landscape-wildfire interactions in Mediterranean Europe

to address and proposed policy and landscape management responses (Moreira et al. 2011).

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1. Introduction

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1. 1 Climate Change

Planet Earth formed

approximately 4.6 billion years

ago. Fluctuations in climate have

occurred throughout Earths

history, following a cyclical

pattern ranging from periods of

warming to ice ages. Historically,

there has been a strong correlation

between atmospheric carbon

dioxide levels and atmospheric

temperatures (Figure 1). Recently,

specifically since the Industrial

Revolution, there has been a

dramatic increase in carbon

dioxide emissions due to

anthropogenic activities. This has

led to an increase in global temperatures (Whittingstall, 2012). Temperatures have risen in recent

years; for example, Whittingstall (2012) documented an increase of about 0.7C from normal

values (Figure 2).

This increase in temperature, while seemingly insignificant, has many pervasive and

devastating impacts throughout the worlds ecosystems. As temperatures increase, tolerance

limits are breached, forcing species to relocate to new elevations and latitudes. This poses a

Figure 2. Fluctuations of temperature and carbon dioxide levels in Antarctic

ice cores (Whittingstall, 2012).

Figure 1. Global temperature anomalies since 1870 (Dahlman, 2009).

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threat to native species in these regions as it can alter ecosystem functioning through different

interactions (Malcom & Pitelka, 2000). This is one of many ways that ecosystems are altered as

a result of a warming climate. A further facet of climate change is an increase in the intensity

and frequency of extreme climate events (IPCC, 2007). For example, as sea and atmospheric

temperatures increase, hurricanes are forecasted to increase in frequency and severity (IPCC,

2007). The Intermediate Disturbance Hypothesis shows the relevance of increasing extreme

climate events in terms of ecosystem dynamics. A change to an ecosystems disturbance regime

may result in an increase or decrease in biodiversity based on the specific system being

investigated. Many tactics are being investigated as potential solutions for ecosystem defense

and remediation in response to climate change-induced natural disasters.

Based on the observations of increasing climate change and natural disasters, it is

extremely important to understand and adapt to changes that this will cause within natural

ecosystems. With this in mind, it was decided that the focus of this report would be divided into

three sections, based on three research questions:

1) How do ecosystems respond to climate change and how can we predict these changes?

2) What are the impacts of climate change-induced natural disasters within an ecosystem?

3) What measures, based on ecological principles, can be taken by humans to help

ecosystems affected by various climate change-induced natural disasters?

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2. Synthesis

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Question 1

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2.1 Question 1: Response and Prediction of Changes

2.1.1 Introduction

The synthesis of this concept addresses the question: What are the responses of species

and ecosystems to climate change and how can we predict the overall impact of these responses.

This synthesis will discuss responses observed in both terrestrial and marine environments,

touching on similar points relevant to both of these ecosystems.

2.1.2 Terrestrial Environments

Although land-use change is the main cause of biodiversity loss due to habitat

destruction, climate change is becoming an increasing threat to terrestrial ecosystems (Dawson et

al. 2011). Species have evolved under a particular set of conditions and climate warming is

pushing these organisms to their tolerance limit and upsetting the delicate balance of the

ecosystem as a whole.

2.1.2.1 Range Shifts

Organisms and species can respond in many ways to a changing environment. Many

species will migrate to a region where environmental conditions are the same as those to which

they have adapted. Range shifts have already been reported with many different arthropods in

terrestrial ecosystems. In the absence of extreme winter temperatures in a warming climate,

these organisms are able to survive through the winter, allowing for a northward movement of

their range (Tuite et al. 2013). These species are then considered to be invasive species and can

often have detrimental impacts on the ecosystems that they enter. For example, the deer tick, a

transmitter of Lyme disease caused by bacteria in the genus Borelia, is spreading throughout

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higher latitudes of North America, affecting many lifeforms (Tuite et al. 2013). Another example

of a species invading a terrestrial ecosystem is the Mountain Pine Beetle, which are also

increasing in range due to less extreme winter temperatures. These beetles cause widespread

die-offs of tree stands and a resulting increase in forest fires (Kurz et al. 2008), ultimately

resulting in a positive feedback to climate warming. Expansion of ranges will be a required

response to climate change by many species, both beneficial and non-beneficial to humans. Since

many desirable organisms are limited by physical habitat barriers caused by fragmentation,

efforts can be put towards facilitating the migration of these species to more suitable

environments (Dawson et al. 2011). This could serve as an effective conservation strategy for

species at risk.

2.1.2.2 Phenotypic Plasticity and Phenology

Along with the previously discussed migration strategies, terrestrial organisms can cope

with changing conditions in other ways. One method is adaptation, the natural selection of genes

that incur a higher fitness. This is a long-term response and effects species rather than

individuals. Short-lived species with high reproduction rates will be able to adapt more quickly

to changing conditions and therefore be more likely to survive in the long term. Phenotypic

plasticity, the ability of an organism to change the phenotype expressed under different

environmental conditions, is another mechanism used (Bradshaw & Holzapfel, 2006).

Phenotypic plasticity has been demonstrated in response to changing phenological events for

terrestrial ecosystems (Bradshaw & Holzapfel, 2006). A phenological event occurs periodically

in response to seasonal cues. If two trophic levels are adapted to different environmental cues

that do not co-vary under global warming, there will be a mismatch between these species. For

example, European Great Tits feed caterpillars to their young and therefore, the success of their

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offspring is dependent on the availability of this food source (Bradshaw & Holzapfel,

2006). Global warming has resulted in snowmelt occurring on an earlier date and therefore an

earlier spring. As a result, caterpillars have been reaching maturity and therefore peaking in

abundance earlier. The Great Tits, however, have not been hatching at an earlier date and as a

result there is a mismatch between these two trophic levels (Bradshaw & Holzapfel, 2006). The

Great Tits most able to modify their time of egg-laying will have the most reproductive

success and therefore, there will be a directional selection for this trait (Bradshaw & Holzapfel,

2006). This case study shows an adaptive shift to birds with greater phenotypic plasticity.

2.1.2.3 Predicting Changes

In light of current trends of climate change, it is important to know whether organisms

have the necessary genetic architecture to respond to expected temperature changes or whether

they must migrate. Studying terrestrial organisms tolerance ranges for different physical

parameters (i.e. temperature) can reveal the environments in which organisms can inhabit.

However, in order to determine the environment in which an organism will inhabit, the

ecological context must be considered. This refers to the concept of the fundamental niche versus

the realized niche. For example, a particular species may be able to inhabit a region with higher

temperatures, but its food source cannot. It is often considered easier to predict how organisms

will respond to warming temperatures rather than how ecosystems will respond. This

information can then be integrated with information on how terrestrial ecosystems have changed

in the past to create models, such as climate envelope models (CEMs), that will predict future

changes and facilitate the application of human-mediated conservation strategies (Duncan et al.

2009).

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CEMs are used to determine the range of a species in a different climate (Duncan et al.

2009). These models have been criticized because they do not factor in variables other than

climate, such as biotic interactions, dispersal limitations and environmental constraints (Duncan

et al. 2009). If a CEM can accurately predict a species range under different climates, then it is

assumed that climate limits distribution. CEMs were developed for South African dung beetles in

their native region and subsequently were used to predict their range when introduced to

Australia. The predicted and actual ranges were not always the same for the introduced species,

indicating that non-climatic variables were having an impact (Duncan et al. 2009).

More extreme results of climate change can include a decreased abundance and local

extirpation of species when insufficient time is available for them to adopt or evolve avoidance

strategies (McCain & King, 2014). In order to assess the vulnerability of a species to climate

change, three components must be analyzed: exposure, sensitivity and adaptive capacity

(Dawson et al. 2011). CEMs only explore exposure, which is the predicted change in climate for

the range of the species. Adaptive capacity and sensitivity takes into account the ability of

species to respond with phenotypic plasticity, adaptation, and migration (Dawson et al. 2011).

Furthermore, vulnerability assessments have been suggested to identify which species will be

most at risk in a changing climate (Dawson et al. 2011). For instance, traits that have been

associated with higher risk include poor dispersal abilities, long generation times, low

reproductive output, large body size and small geographic ranges (Dawson et al. 2011). Long

generation times and low reproductive rate result in higher risk because they decrease a species

ability to genetically adapt to environmental changes. It was hypothesized for terrestrial

ecosystems that smaller animals may be able to persist as climate warms by taking advantage of

different microhabitats (McCain & King, 2014). In addition, it has been shown that those species

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that are at higher latitudes and elevations such as polar bears, pika and caribou are at a

greater risk (McCain & King, 2014). Lastly, species with larger relative brain sizes are likely

better respond to challenges posed by global warming, such as colonizing new regions (Sol et al.

2006). For example, a study done by Sol et al. (2006) showed that bird species with larger

relative brain sizes experience less mortality.

2.1.2.4 Species management

Methods have been developed

for determining whether a particular

species requires intervention (Figure 3).

They are based on the same three

factors of vulnerability discussed

previously: exposure, adaptive capacity

and sensitivity. Exposure can be

predicted from climate models, while

the other two variables are

physiological characteristics. Species with low exposure, high sensitivity and low adaptive

capacity are not at risk currently but must be monitored because minor changes in environment

would put them at risk. Contrastingly, species with high exposure, low adaptive capacity and

high sensitivity require high intervention (Dawson et al. 2011). However, low-intensity

intervention is required for species with high exposure, low sensitivity and high adaptive

capacity. An example of low-intensity intervention is in reserves in Yellowstone, WY, where

there is the occasional introduction of top predators and eradication of invasive species (Dawson

et al. 2011). Intervention may require costly procedures and therefore economic costs must be

Figure 3. This diagram was used to represent the vulnerability of a

species or ecosystems based on its exposure to climate change (x-axis)

as well as its sensitivity and ability to adapt (y-axis) (Dawson et al.

2011).

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reviewed as well (Dawson et al. 2011). In addition, the economic services provided by an

ecosystem will be taken into account when deciding what efforts should be applied for the

species (Dawson et al. 2011).

2.1.2.5 Future Direction

There are many areas where further research is needed. Ecologists, climatologists and

physiologists should continue to work together to develop models to be used to predict

ecosystem changes in light of a changing climate. A part of this should include further research

on the tolerance limits of different species. In addition, human intervention costs should be

weighed using the adaptive capacity, sensitivity and exposure of a species to determine whether

the benefits would outweigh the costs. If decided that intervention is required, different

management practices such as translocation of species or facilitating migration could be

solutions to easing the challenges faced by species in a warming climate.

2.1.3 Marine Environments

Climate change is having a significant impact on the worlds oceans and many of these

changes are affecting levels of aquatic biodiversity. Some of these changes include increases in

ocean surface temperatures, increasing acidification of the water, and rises in ocean levels. These

changes in the oceans environment are leading to different species compositions. Many of these

species have to adapt to their ever-changing environment in ways that they have never had to

before.

2.1.3.1 Changing Phenology

The phenology of many species is changing in response to the climatic shift and this is

causing cascading effects throughout aquatic ecosystems on many different species. One of these

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changes is affecting different members of the plankton taxa. A long-term study from 1958 to

2002 determined that plankton blooms across all taxa have been changing (Edwards &

Richardson, 2004). Many of these species are blooming earlier in the season, which may be

causing a decoupling in the feeding time of other species which depend on the plankton as a food

source (Edwards & Richardson, 2004). One phylum in particular, Echinodermata, was shown to

have changed its blooming time to 47 days earlier fron 1958 to 2002 (Edwards & Richardson,

2004). This study shows that although some plankton species moved drastically forward in their

blooming event and some backwards there was an overall trend of deviation from their original

blooming times (Edwards & Richardson, 2004).

2.1.3.2 Temperature Effects

As stated previously, changes in ocean temperatures are affecting the species that survive

within them. Although specific effects range from species to species, the general ecology of the

oceans have been changing due to the increase in ocean temperature resulting from

anthropogenically-induced climate change. Many species within the oceans already lived close to

their thermal tolerance levels prior to recent warming and so rises in ocean temperatures is only

expected to be negatively impacting many of these species (Hughes et al. 2003). An example of

this negative influence is the increase in mass bleaching events of coral in the past century

(Hughes et al. 2003). These mass bleaching events, which will be discussed further in the

synthesis of the third question, result in the destruction of coral reef systems which support a

large proportion of the oceans biodiversity.

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2.1.3.3 Range Shifts

Along with changes in species phenology, climate change has also had an effect on

species ranges. Species that are capable of migration are moving into new territories which are

now more suitable to their survival. These species are following the favourable conditions that

they require for survival which include, but are not limited to environmental temperature, food

availability, and more. As surface temperatures in the tropics and mid-latitudes warm beyond

species tolerance levels, there is a general migration towards the polar regions of the planet

where the temperatures are more fitting for their survival (Mueter & Litzow, 2008). One

dramatic example of this range shift is that of the diatom Neodenticula seminae, which occurred

in 1999. This species, a common primary producer in the North Pacific, was able to infiltrate the

North Atlantic for the first time in 800,000 years due to decreased Arctic ice cover (Doney et al.

2012). Continuing with this trend, migratory changes have also been seen in the North Sea, a

portion of the Atlantic located between the United Kingdom, Norway and Germany. From 1986

to 2005 the species richness in the North Sea increased by nearly 50% (Doney et al. 2012). The

main increase in this richness came from increases in small-bodied southern species which, due

to warming water temperatures, were able to infiltrate and expand into the new North Sea

environment. Along with the North Sea example, there have also been noticeable differences in

the fish species that reside in the North Atlantic. In a study that examined a range of fish species

in this area, it was found that about half of the fish species studied had moved northward and

could now be found at deeper profiles of the ocean (Nye et al. 2009). Along with this discovery,

it was found that the temperatures which the fish were living were not different from where they

were found previously. This suggests that fish species will continue to adapt their ranges as long

as they are able to keep a constant environmental temperature (Walmsley, 2012). While this

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tactic will work for species in the near future it is not a sustained method of survival. As climate

change continues to take its toll, eventually species will travel as far north or southward as they

can go. With nowhere further to go, these species will most likely die off as they are no longer

able to adapt to the changing oceanic environments.

2.1.3.4 Predicting Changes

Predicting the changes in ecosystems that will result from climate change is a difficult

task as there are many complex processes involved in natural environments. While it is well

known that climate change is having a large impact on the species in the oceans, currently there

is no way to completely predict what will happen. Some scientists suggest a top-down approach

(predators to primary producers) while others suggest that a bottom-up approach (primary

producers to predators) is best to predict what will happen to the oceans in the future. Though

these are both valid approaches, individual areas of the oceans will most likely be affected to

different degrees by functional redundancy (the amount of species that perform similar function

in the environment), the rate at which the community structure is changing, as well as further

methods of community change (Doney et al. 2012). Thus, further knowledge of climate changes

impacts on community structure is required.

2.1.3.5 Future Directions

Further research needs to be done in a couple of different areas in order to better

understand the effects that climate change is having on marine species. Firstly, better

understanding of the warming trends in the oceans will allow more accurate predictions on where

species will migrate to and approximation of the time it will take for this migration to occur.

Furthermore, research into the tolerance limits of marine species will better help to predict which

species will be most affected by further climate change and ocean environmental changes. These

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two areas of study would greatly increase the accuracy of predictions being made by scientists

across the globe in this area of study.

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Question 2

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2.2 Question 2: Climate Change-Induced Natural Disasters

2.2.1 Effects of Climate Change on Occurrence of Natural Disasters

As mentioned previously, an increase in the frequency and intensity of extreme climate

events (IPCC, 2007). In the future, a warmer climate will result in increased droughts (IPCC,

2007). Increased temperatures also allow the atmosphere to hold more water, which causes an

increase in intense precipitation events, leading to flooding (IPCC, 2007). In addition, the

increased prevalence of precipitation can lead to an increased frequency of rainfall-triggered

landslides (Burma & Dehn, 1998). Models have also projected an increase in the severity of

tropical storms, with greater intensities of precipitation and winds (IPCC, 2007). After a

hurricane, damaged trees and plants increase the risk of wildfire which may be exacerbated by

temperature increases and summer dryness (Turton, 2012). Some of these projected changes

have already been observed, including an increase in frequency of heat waves and intense

precipitation events, as well an increase in the average number of Category 4 and 5 hurricanes in

the past 30 years (IPCC, 2007).

2.2.2 Disturbances, Intermediate Disturbance Hypothesis and Resilience

In 1978, Joseph Connell proposed the Intermediate

Disturbance Hypothesis, suggesting that species richness

of an ecosystem is highest at medium levels of disturbance

(Figure 4) (Wilkinson, 1999). Low levels of disturbance

will lead to lower species diversity due to competitive

exclusion while high levels of disturbance will lead to

Figure 4: Graphical representation of the

Intermediate Disturbance Hypothesis

showing species richness for different levels

of disturbance (Wilkinson, 1999).

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lower levels of species diversity due to the persistence of pioneering species (Wilkinson, 1999).

This theory demonstrates the importance of disturbance regimes in maintaining a diverse

ecosystem.

Disturbance can be classified in multiple ways based on their cause (either natural or

anthropogenic) or severity and frequency (chronic, stochastic or catastrophic) (Finkelstein et al.

2010). Chronic disturbances are constantly occurring and are generally of low intensity (i.e.

seasonal harvesting), stochastic disturbances are of low to moderate intensity and occur

erratically (i.e. weather events), and catastrophic events occur rarely but have the potential to be

of a very high intensity (i.e. hurricane) (Finkelstein et al. 2010). Thus, the disasters previously

discussed can be attributed primarily to natural causes, despite their anthropogenically-induced

increases, and can be classified as either stochastic or catastrophic.

While natural disasters have the potential to cause a severe short-term population decline,

some species have developed defenses for these naturally occurring disturbances (Finkelstein et

al. 2010). A resilient ecosystem is one that can resist damages caused by disturbance and retains

the same species composition without undergoing a phase shift (Turton, 2012). A phase shift

involves an abrupt, often permanent change of ecosystem composition and function into a new

qualitative state (ex. phase shift between vegetation types), once certain environmental

thresholds have been crossed (Turton, 2012). Phase shifts depend on both the external

disturbance to the system as well as the internal resilience of the system (Turton, 2012).

Environmental degradation of an ecosystem as well as disturbances of greater severity would

increase the potential for a phase shift.

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2.2.3 Introduction to Climate Change-Induced Natural Disasters

Despite most assumptions of their destructive impacts on ecosystems, many natural

disasters result in no significant ecosystem impacts, and some even have positive impacts on an

ecosystem (National Research Council, 1999). Climate change-induced natural disasters include

many different types of disturbances and therefore have differing effects on ecosystems. It is

often assumed that due to their greater spatial and temporal extent, disturbances such as droughts

and floods generally create greater environmental and long lasting impacts compared to

hurricanes, severe winter storms and thunderstorms (National Research Council, 1999). Natural

disasters are expected to have a more significant effect on small and isolated populations, which

can lead to extinction if they are endemic to the area of the disturbance (Dalsgaard et al. 2007).

The synthesis of this concept addresses the question: What are the impacts of climate change-

induced natural disasters within an ecosystems.

2.2.3.1 Floods

Floods play an important role in shaping an ecosystem (LeRoy Poff, 2002). In general,

large floods are considered to have positive impacts on some species and negative impacts on

others (National Research Council, 1999). Floods can often directly kill organisms such as small

fish and invertebrates through scouring, burial or displacing them into less favourable habitats

(LeRoy Poff, 2002). However, they also create new habitat, which many species are adapted to

exploit. Within floodplains, floods serve to saturate organic matter that has accumulated,

promoting the cycling of nutrients and therefore boosting the ecosystems productivity (LeRoy

Poff, 2002). This process has been shown to increase the production of various types of plankton

which supports juvenile fish, leading to increased yields from some floodplain fisheries during

flood pulses (LeRoy Poff, 2002). Some species rely on flooding as a part of their lifecycle, for

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example Cottonwood trees, which rely on seasonal snowmelt flooding in order to transport their

seeds (LeRoy Poff, 2002). Another example of the dual effects of a flood is in a great flood that

occurred in the American Midwest in 1993, where many fish species were able to spawn on the

inundated floodplain, which also increased the amount of food present for wading birds

(National Research Council, 1999). However, this flood had a negative impact on long-lived

species such as trees due to the stress caused by the long inundation (National Research Council,

1999). An increase in the magnitude and/or frequency of flooding is expected to cause a non-

uniform response throughout river ecosystems due to their variability (LeRoy Poff, 2002).

Seasonal floods in some cases are expected to occur up to one month earlier in the year, which

would have a significant impact on species such as riparian trees that rely on snowmelt to

transfer their seeds (LeRoy Poff, 2002).

2.2.3.2 Droughts

Droughts, unlike floods, are generally seen to have mostly negative impacts on

ecosystems (National Research Council, 1999). The millennium drought in Australia, had

effects throughout most southern and eastern parts of the county, lasting for over a decade (Bond

et al. 2008). In a study of its effects within aquatic ecosystems it was found that drought can

cause the waters edge to contract, effectively isolating habitats and stranding different species.

This can lead to death of robust riparian trees (Bond et al. 2008). In testing the effects of

drought on a forested ecosystem in the United States, one study found that droughts can cause a

decrease in growth or mortality of some species as well as have indirect effects by making trees

more susceptible to other biotic and abiotic factors such as fire and disease (Klos et al. 2009).

There was a decrease in mean annual growth seen in several tree species as the severity of

drought increased (Figure 5) (Klos et al. 2009). Different species act differently to drought

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depending on their tolerance to this form of disturbance (Klos et al. 2009). The insignificant

amount of change in annual growth rate within the Oak species shows a greater tolerance of

drought in this species (partially due to greater root depth) and suggests that an increase

Figure 5. Mean annual relative growth rates by drought class (no drought (1) - severe drought (4)) for

pine, oak, and mesophytic species groups (Klos et al. 2009).

in frequency and/or intensity of drought may cause a shift to an Oak tree-dominant community

(Klos et al. 2009). Despite the fact that ecosystems with seasonal droughts are well-adapted to

this disturbance regime, severe drought conditions can push the limits of this adaptation (Bond et

al. 2008). Additionally, due to their potentially large spatial scale, droughts have the ability to

affect vast areas and cause complete species extinctions (Bond et al. 2008).

2.2.3.3 Forest Fires

As mentioned, the occurrence of forest

fires is increasing due to global climate change.

This is one of the most dominant type of

disturbance of the forests in the United States

(Flannigan et al. 2000). Total area burned is

strongly related to an increase in both observed Figure 6. Graphical summary of the correlation between

temperature increase and area burned(Gillett et al. 2004)

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and simulated temperatures (Figure 6) (Gillett et al. 2004). This increase in fire is also aided by

an increase in cloud-to-ground lightning strikes, which can serve as ignition agents (Flannigan et

al. 2005). Forest fires, in some cases, can be beneficial to an ecosystem. However, if they occur

too frequently, or not frequently enough, they can upset the delicate balance in place (Flannigan

et al. 2000). The severity of a fire is measured by the amount of fuel it consumes; the more fuel

eaten up by the fire, the more severely it is classified (Flannigan, et al. 2000). Fire causes an

increase in the erosion of soils as well as the surface runoff (Ahlgren & Ahlgren, 1960). Ahlgren

and Ahlgren (1960) described how the loss of vegetation on stream banks post-fire led to the

collapse of these banks. The erosion and runoff was a product of the fire causing lower

infiltration rates of the soil, up to 38 percent in some studies (Ahlgren & Ahlgren, 1960). In some

cases, the decrease in the soil fertility caused very young seedling growth to be impaired

(Ahlgren & Ahlgren, 1960). Germination has also been reported to be much lower on soils

covered in ash (Ahlgren & Ahlgren, 1960). In some cases, however, burning of the soil has

proven to increase plant growth, specifically the germination of the Scots pine (Ahlgren &

Ahlgren, 1960).

There are also a variety of impacts on the vegetation of burned ecosystems. In one study,

it was found that burning increased growth of lichens and mosses. The removal of upper

vegetation by the burning caused an increased in sunlight, which was beneficial for growth of

vegetation on the forest floor (Ahlgren & Ahlgren, 1960).

2.2.3.4 Landslides

Landslides are natural disasters associated with the destructive repositioning of soil and

sediment from an area of higher elevation to one of lower elevation. Typically, they are caused

by precipitation or earthquakes and can result in substantial changes in the local ecosystem

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composition due to their destructive nature (Walker et al. 1996). Following heavy precipitation,

the saturation of soils on steep slopes can result in slips, which may cause damages to areas

below (Iverson, 2000). With increasing temperatures and changes in rainfall patterns, some have

predicted that small-scale landslides will decrease in frequency due to increased evaporation

rates, resulting in the future risk of large-scale landslides (Collison et al. 2000). In addition to the

initial damages caused by a landslide on the local ecosystem, the introduction of a new layer of

topsoil and the clearing of foliage in the surrounding area can present the opportunity for the

establishment of pioneering species. Most notably, the presence of seeds and nutrients in newly

laid soil can determine how rapidly pioneer species will establish themselves before succession

of long-standing species (Walker et al. 1996). However, the soils of landslides tend to possess

less organic matter than the areas below them, which can significantly impact the rate at which

these areas are able to recover. In a study of 12 landslides by Walker et al. (1996), it was found

that soil nutrients in the upper levels took up to 55 years to reach comparable levels to the

nutrient levels of the indigenous soils below. Though recovery from a landslide can be slow, the

availability of cleared topsoil means that pioneer species will eventually establish themselves,

fuelling the recovery of the local ecosystem. Despite this, recovery of long-established species

can be a slow process and with the predicted increase in large-scale landslides, such ecosystems

face an increased threat (Collison et al. 2000).

2.2.3.5 Hurricanes

Hurricanes are considered to be a large, infrequent disturbance (Lugo, 2008) and

generally have less of an effects on an ecosystem (National Research Council, 1999). In a review

of literature on the effects of hurricanes in forested ecosystems, it was found that while

hurricanes have many visible effects, such as defoliation, debris accumulation, etc., they rarely

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cause significant changes in ecosystem processes (Lugo, 2008). With a path of 50-150 miles

wide, damages often include erosion of shorelines as well as tree destruction (National Research

Council, 1999). Any effects on fauna in these ecosystems, including bird and lizard species, did

not occur during the actual hurricane event, but rather as a result of habitat destruction (Lugo,

2008). For example, the Roe Deer was minimally impacted by Hurrican Lothar, which passed

through their habitat in 1999. Instead, populations actually increased following the hurricane due

to the creation of openings in their forest habitat, which enhanced their foraging abilities

(Gaillard et al. 2003). Following Hurricane Larry on the West Tropics Forest region of northeast

Australia, many endemic mammals, as well as many beetle populations, were not significantly

impacted by the event (Turton, 2012). In addition, invasion of weeds in riparian areas that did

occur as a result of the disturbance were often short-lived, dying out following regrowth of the

forest canopy within 1-2 years (Turton, 2012). Damages are often dependent on location within

the path of the hurricane, being generally less extensive further from the center of the storm

(Turton, 2012).

2.2.4 Conclusions

Although natural disasters tend to be associated with negative impacts, it can be seen that this is

not always the case. Ecosystems have adapted to specific disturbance regimes and can even

benefit from certain conditions that are created following such disturbances. Though many

predictions can be made, it is not known what effects an increase in frequency and severity of

these events will have on ecosystems, even ones with species well adapted to these events.

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2.2.5 Future Directions

The effects of natural disasters on ecosystems are many and varying, leading to a diverse

and complex area of study. With such complex processes and systems involved, it is unlikely

that the effects of any type of natural disaster will be completely understood and predicted.

However, further research into this complex topic as well as into climate models projecting

changes in occurrence of these disturbances will be integral in allowing for more effective

planning of the protection or remediation of ecosystems. General circulation models (GCM) are

commonly used in studies to simulate this future climate change and are built around the effects

of various concentrations of greenhouse gases in the atmosphere (Flannigan et al. 2005). They

are multipurpose and can be used to explore the many effects of these gases on oceans and land

surfaces (Flannigan et al. 2005). For example in one study it was projected that the forest area

burned by the end of the century would increase by anywhere from 74% to 118% (Flannigan et

al. 2005). These models will likely never be completely accurate, therefore, there is always room

for improvement. With the predicted increase in frequency of such events, further research into

the effects of compounded disturbances within an ecosystem and how this affects the ecosystem

resilience will also be of increasing relevance.

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Question 3

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2.3 Question 3: Ecological Based Human Measures

2.3.1 Introduction

The geophysical events mentioned previously, including earthquakes, landslides,

flooding, and hurricanes, have been classified as natural disasters as a result of human influence

(Alcantara-Ayala, 2002). As previously discussed, climate change, although a natural

phenomenon, has been accelerated by human activities and has had detrimental impacts on

ecosystems around the world, both marine and terrestrial alike (OBrien et al. 2006). There are

impending risks to ecosystems associated with increasing natural disasters induced by

accelerated climate change. Since little can be done to resolve anthropogenic mistakes

committed against the environment, greater attention needs to be paid towards preparing for the

expected changes, as opposed to remediating damages done. The synthesis of this concept

addresses the question: what measures, based on ecological principles, can be taken by humans

to help ecosystems affected by various climate change-induced natural disasters. Management,

restoration, and conservation are the three approaches humans can take to help combat the

effects of natural disasters on terrestrial ecosystems, wetland habitats, and marine environments

respectively.

2.3.2 Management Options for Terrestrial Ecosystems Affected by Wildfires

Projected climate change for the 21st century is expected to directly and indirectly alter

climate-sensitive processes of ecosystems. It has also been shown that climate change will bring

about changes in terrestrial disturbance regimes, particularly regarding wildfires (Schumacher &

Bugmann, 2006). Recent studies have begun to focus on assessing the interactions amongst

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forest dynamics, climate change, and large-scale disturbances such as fire in order to develop

effective forest management strategies.

Siberia, Canada, Alaska and the Western United States are likely to be most greatly

affected by increased wildfires associated with climate

change (Flannigan et al. 2005). Table 1 summarizes the

fire properties in Canada, an area of growing

importance due to its vulnerability with respect to

future climate change. Similarly, the Western United

States is of even greater concern due to the longer fire

seasons, drier conditions, increased amounts of fuel,

and increased lightning storms, all of which are associated with climate change (Westerling et al.

2006). The infographic on wildfires in Western US provided by the Union of Concerned

Scientists (2013) illustrates the expected effects (Figure 7). Although these areas are permitted

to have prescribed burns and,

despite current fire management

which is able to control close to

97% of all fires before they reach

200 ha in size, 3% of all fires

surpass human capability to

suppress and account for almost

97% of the total area burned

(Stocks et al. 2002). This is alarming considering the expected increases in numbers of longer

and larger wildfires. Weather variables, such as atmospheric moisture, wind, and precipitation

Table 1. Cumulative area burned, forested area and

percent area burned for ecozones in Canada

between 1980 and 1999 (Flannigan et al. 2005).

Figure 7. Infographics provided for public distribution depicting the current trends

of wildfires and climate change in western United States (Union of Concerned

Scientists, 2013)

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patterns have all been shown to influence wildfires greatly. However, temperature appears to be

the most important variable as an increase leads to drier fuels, due to increased

evapotranspiration, and lightning storms (Flannigan et al. 2009).

Fire management via landscape policies is not a new concept, and has been occurring

since the early 1900s in certain areas of the world. However, although certain countries,

specifically Canada, are recognized as leaders in fire management, there is a need for better

policies focussed on prevention rather than suppression. This is supported by the evidence

showing that fire suppression policies can increase fuel accumulation and incidentally increase

wildfire severity. Adaptation to the emerging reality of longer fire seasons, increased fire

occurrences, and increased fire intensity will likely include the recognition that current

management policies will be insufficient in handling fire in the near future. Therefore, current

landscape management policies should make a strategic shift towards adopting proactive

planning strategies by means of developing preventative approaches to mitigate worsening

wildfires (Stocks et al. 2002). At the ecological level, forest planning can integrate area-wide fuel

modifications which are extensive applications of fuel treatments at the forest stand level that

include reduction of fuel load and disruption of fire favoured habitats (Moreira et al. 2011). Such

treatments refer to fuel type conversion which involves replacing highly flammable vegetation

with low growing, less fire-prone species (Rigolot et al. 2009). Another viable option is the

application of a fuel break strategy, which involves fragmenting large areas of fire-prone

landscape with a network of less fire prone corridors (Moreira et al. 2011).

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2.3.3 Restoration Strategies for Wetland Habitats Affected by Storm Surges

The risk of flood disasters, attributed to sea-level rise and increased instances of

hurricanes and associated storm surges, is increasing for many coastal areas around the world as

a result of global climate changes. At the same time, current conventional coastal engineering

solutions, including sea walls, dykes and embankments, are becoming increasingly challenged by

environmental pressures and in some cases are no longer fulfilling their protective role towards

coastlines (Temmerman et al. 2013). For example, Hurricane Katrina devastated New Orleans in

2005 after the levee system failed, Hurricane Sandy hit New York in 2012, and Typhoon Haiyan

in 2013 severely impacted the central Philippines (Temmerman et al. 2013). These, and similar

low-lying coastal areas around the world, require better flood protection techniques. Ecosystem

creation and restoration can provide protection from these storms by reducing storm surges and

acting as buffers against intense hurricanes and typhoons.

Recent climatic research indicates that major hurricanes, considered category 3 or higher

on the universally used Saffir-Simpson scale, may intensify in response to warming sea surface

temperatures associated with global

warming. This is demonstrated by a decline

in number and percent of category 1 storms

and an increase in category 4+5 storms

(Figure 8) (Webster et al. 2005). Harper

(2011) discuss the addition of a sixth

category to the current SaffirSimpson

category 1-5 scale to address storms outside this range of severity. What is even more concerning

is the combination of expected sea level rise with increased coastal storms and subsequent

Figure 8: Intensity of hurricanes according to the Saffir-Simpson

scale from categories 1 to 5. It is seen that for both number of

intense hurricanes and percent of intense hurricanes, the number of

category 4 and 5 hurricanes is increasing. Category 1, 2 and 3

hurricanes appear to be decreasing (Webster et al. 2005)

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intensification of storm surges (Mousavi et al. 2011). The reality is that the coupled impact of

storm intensification and sea level rise is projected to increase hurricane flood elevation by an

average of 0.5m and 1.8m respectively, by the 2030s and 2080s (Mousavi et al. 2011). Therefore,

in preparation for expected changes, coastal protection management needs to develop strategies

that can withstand future storms.

Conventional coastal engineering, such as the building of structures including sea walls

and embankments, is widely accepted as the most appropriate solution for combating flood risks

associated with coastal storms. However, these defenses are becoming increasingly recognized

as unsustainable and unsuitable for keeping up with increasing flood risk. Furthermore,

application of conventional coastal engineering often hinders the natural capacity of shorelines to

respond to sea level rise, which ultimately leads to land subsidence as they compromise the long-

term build-up of beaches and dunes (Temmerman et al. 2013). Recently, application of

ecosystem-based-defense, which is directed on restoring the natural capacity of coastlines to

handle intensification of storms with the goal being long-term sustainability, has intensified

(Temmerman et al. 2013). The foundation of this concept is creation and restoration of

ecosystems such as tidal marshes, mangroves, dunes and coral reefs to reduce storm surges and

keep up with sea-level rise by natural accretion of sediments. Specifically, this approach can be

successfully implemented in areas that have become increasingly urbanized along shorelines.

Comparison between conventional coastal engineering and ecosystem-based-defence was

completed to visually demonstrate the concepts behind each approach (Figure 9). For cities

located in estuaries or deltas such as New Orleans, London and many large Asian cities in the

low-lying areas of the continent (dark and pale green in Figure 10) restoring large tidal

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Figure 9. Visual representation of the differences between conventional coastal engineering (left) and ecosystem-based coastal

defence (right). Blue arrows indicate an increase in intensity of storm waves and storm surges. The green arrows represent the

wetland sedimentation stimulated by storm waves. (Temmerman et al. 2013)

Figure 10. Map showing the global need for coastal flood protection and large-scale examples. Potential application of

ecosystem-based defence is also shown: dark green has the greatest potential, pale green has moderate potential, orange

represents cities with minimal potential, blue are cities existing directly on coasts with the least potential (Temmerman et al.

2013)

marshes and mangroves along the coasts will provide many benefits (Temmerman et al. 2013).

Not only will it provide extra water storage areas and friction, which mitigates the landward

transgression of storm surges, it will provide added benefits associated with sustainability, which

is discussed in the integration section. Studies have been completed on viability of this flood

defense approach in areas around the world. For instance, Zhang et al. (2012) demonstrated,

using field observations, how the 6-30 km-wide mangrove forest along the Gulf Coast of South

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Florida effectively attenuated storm surges from the Category 3 hurricane Wilma and resulted in

a surge amplitude decrease at a rate of 50cm/km across the forest. The results of this study show

that, with no mangrove forest (black

solid line), distributions of peak surge

heights were well above those of areas

where mangrove zones of varying

widths were present (solid coloured

lines which indicate width of mangrove

zone) (Figure 11). This study provides

evidence for the ability of coastlines,

including mangroves for example, to

buffer the impacts of waves, storm

surges and tsunamis on coastal properties (Zhang et al. 2012). In a similar sense, a study

performed by Wamsley et al. (2010) demonstrated the potential for wetlands to reduce surges

based on observations in South-eastern Louisiana along the coast of the Gulf of Mexico.

Although there is significant variability in the ability of wetlands to successfully protect

coastlines against storms, which is attributed to both key storm parameters and wetland

properties, there is evidence that in general, wetlands do attenuate surges and therefore should be

considered when developing comprehensive coastal protection plans (Wamsley et al. 2010).

2.3.4 Conservation Strategies for Marine Environments Affected by Warming

Habitats such as marine environments, specifically coral reefs, are susceptible to the

negative impacts of climate change. Separate from the expected increases in storm intensity, sea

level rise, freshwater influx, and ocean acidification (lowering of pH as oceans absorb increasing

Figure 11. The distributions of peak surge heights along four profiles across

mangrove zones of varying widths (coloured lines). The black solid line

represents surge amplitudes along a profile without mangrove effects

(Zhang et al. 2012)

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levels of carbon dioxide), mass bleaching events are thought to have the greatest negative effect

on corals and has increased over the past two decades (Keller et al. 2009). As the Earth warms,

sea surface temperature increases along with ocean temperature in general which can result in

coral bleaching. Along with the potential damages caused by climate change, human induced

fragmentation of coral reef habitats undermine reef resilience and make them even more

susceptible to future climate change. Clearly, the capacity of coral reef ecosystems to withstand

future changes needs to be managed more actively in order to sustain these sensitive

environments. This can be done by implementing networks of marine protected areas (MPAs) to

improve coral reef resilience and sustain corals capacity to persist in changing conditions

(Hughes et al. 2003). Resilience can be defined in several ways, but for marine environments it is

a measure of a systems ability to sustain itself by absorbing perturbations, as caused by climate

change for example, and continue to function successfully (Keller et al. 2009)

Coral bleaching occurs when heat-stressed corals expel the pigmented microalgal

eudosymbionts, called zooxanthellae, which terminates the symbiotic relationship between the

two, ultimately leading to death of corals (Hughes et al, 2003). Bleached corals may recover

their symbiotic populations of zooxanthellae in the weeks and months following the disturbance

events if the conditions were mild and short-lived (Gibson et al. 2007). Recently, however,

mortality of corals has reached 100% more often due to extended periods of stressful conditions

lasting weeks. Repeated instances of these increased stressful periods due to recent ocean

warming were not seen until 1979 (Gibson et al. 2007). Since then, hundreds to thousands of

square kilometers of coral reef in almost every region of the world have been affected, with the

most severe global episode of coral bleaching occurring in 1998 when 16% of the worlds corals

died (Hughes et al. 2003). Although climate change has been determined as the major cause of

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mass coral bleaching events, mitigating its effects will not necessarily return the system to its

former state, as climate change is not easily reversible. However, if appropriate conservation

measures are properly implemented, coral reef resilience towards ocean warming can be

improved.

The preceding list of potential effects of climate change on oceans are considered

boundary-less threats in the sense that they have the potential to continuously increase in severity

regardless of what tactics humans adopt at this point to slow the effects of global climate change

(Davis, 2013). Despite the inability of MPAs to protect against these disasters, they do serve as a

significant and useful tool for conservation. For instance, (1) they provide unique protection for

marine ecosystems and may therefore increase the resilience of these habitats to disturbances

caused by climate change; (2) they help maintain the natural range of species (Notarbartolo di

Sciara, 2007; Wells et al., 2008). Networks of MPAs also integrate biological connectivity by

enabling adequate mixing of the gene pool to maintain natural genetic characteristics of the

population, which may also lead to greater resiliency by facilitating evolution of favourable

survival traits (Davis, 2013). Therefore, protection of biodiversity by maintaining the natural

range of species and facilitating development of more resilient ecological functions is a major

role of MPAs. There is a key relationship between resilience and biodiversity as they pertain to

MPAs, which stems from the ecological functions that species, especially corals perform. Each

species is capable of fulfilling a limited number of ecological functions, which accumulate as

more species are added to the ecosystem, generating greater biodiversity (Keller et al. 2009).

These diverse systems have been proven to re-establish ecological functions faster when they are

impaired or lost to perturbations as a result of climate change, for instance (Davis 2013). MPAs

can thus facilitate the maintenance of higher degrees of ecosystem resilience in areas where these

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functions are lost, by providing sufficient protected space and opportunities for these ecosystems

to absorb climatic perturbations without facing further anthropogenic disturbances (e.g. Fishing).

While MPA networks have immense potential for conserving marine biodiversity by improving

ecosystem resilience, they should be established in conjunction with other management strategies

such as fisheries regulations and reductions of land-based pollution if they are to be at all

effective in the near future given the current trends of climate change (Keller et al. 2009).

2.3.5 Future Directions

Future directions in sustainable management of future increases in wildfire occurrence

should focus on assembling flexible management policies that can easily be adapted to situations

on either ends of the severity scale for wildfires. Management of wildfires in peatland

ecosystems as well as areas of permafrost will also become increasingly important. Severe fire

activity in peatlands results in the combustion of deep peat layers which can occur for several

months, releasing continuous greenhouse gases including methane and carbon dioxide

(Flannigan et al. 2009). In the more northern habitats, permafrost can either hinder wildfires or

increase the vulnerability of ecosystems to burning (Flannigan et al. 2009). Future research

should be geared towards identifying which ecosystems these are in order to develop

management strategies for those which are at greatest risk of experiencing negative impacts of

climate change enhanced wildfires.

Application of ecosystem-based defense has increased in recent years, as it is recognized

as a cost effective and sustainable solution. However large-scale implementation of wetland

restoration for food defense is still very limited despite the extreme potential for this method to

reduce effects of flooding associated with rising sea levels and storm intensification. Current

findings on the numerous benefits of ecosystem-based defense demonstrate the potential for

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widespread implementation of this approach and should further stimulate joint research by

ecologists and engineers (Temmerman et al. 2013). Future research should be geared towards

identifying the potential for wider implementation of ecosystem-based defense over larger areas

in order to motivate governments and industries to adopt such restoration techniques.

Marine protected areas have the potential for being effective conservation tools humans

can implement to improve ecosystem resilience against climate change-induced stressors, for

example corals and mass bleaching events. However, spread of disease and the threat of invasive

species is also a reality of these systems that needs to be addressed in future research.

Unfortunately, the same characteristics that make invasive species successful r-strategists, or

invaders, may also make them already adapted to ocean warming which could therefore facilitate

expansion of these species throughout MPAs (Keller et al. 2009). Similarly, pathogens and

diseases are likely to respond positively to the warmer ocean temperatures associated with

climate change. Often, these negative side effects of networks of MPAs spread rapidly due to the

lack of dispersal barriers and eventually compromise the resiliency of species and consequently,

the entire ecosystem (Keller et al. 2009). Future research therefore, should focus on identifying

ways in which these biotic stressors can be reduced or controlled either by minimizing pollution

and overfishing, or by developing strategies to combat these issues. Also, due to the uncertainties

and difficulties associated with managing marine systems, such as expensive data collection,

inability to observe communities directly, and vast areas covered by these expansive habitats, the

importance of more research is essential for the future. Pursuing more detailed understanding of

these systems should therefore be the goal.

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3. Integration

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Integration with:

From the Ground Up

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3.1 Agricultural Implications of a Warming Climate

3.1.1 Impacts of Agriculture on Global Warming

Following the Green Revolution in the 1900s, agricultural intensity has increased in

many countries. This has contributed to the anthropogenically-induced global warming in many

ways. When land is cleared to make way for crops and livestock, trees are cut down and soil is

exposed. This results in an increase in carbon dioxide emissions both directly through the decay

of organic material, which previously sequestered carbon dioxide. In addition, agriculture

increases the greenhouse gases in the atmosphere via direct emissions. Next to transportation,

agriculture is the leading industry in fossil fuel consumption (Hosking, 2009). The transportation

of crops, livestock, pesticides, fertilizers etc. to different locations, as well as the manufacture of

such pesticides and fertilizers, contributes to these emissions. Another important greenhouse gas

is nitrous oxide. Nitrous oxide is a by-product of different microbial processes within the soil

that are referred to as denitrification and nitrification (Cornell et al. 2012). The application of

industrial nitrogen-based fertilizer will increase the nitrous oxide emissions to the atmosphere

(ABARES, n.d.). Park et al. (2012) have found a way to determine where particular nitrous oxide

emissions have originated. This allows for the monitoring of different countries nitrous oxide

emissions resulting from nitrogen-based fertilizer. Many proposals to reduce nitrous oxide

emissions have been made. Reduction efforts may include minimizing the fertilizer applied

before anticipated rainfall because of the fact that moisture increases microbial activity and, as a

result, nitrous oxide emissions (Park et al. 2012). Natural fertilizers, such as legume crops (e.g.

alfalfa and clover) (ABARES, n.d.), could be used versus synthetic fertilizers. Legumes have

symbioses with nitrogen-fixing bacteria and phosphorus-acquiring fungi (Scheublin et al. 2004).

It has been suggested that alternating sugar cane and soybeans (a legume) between growing

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seasons reduces the need for synthetic fertilizer (ABARES, n.d.). In addition, cover crops could

be planted to take up excess nitrogen following removal of crops (ABARES, n.d.). Lastly,

enhanced efficiency fertilizer (EEF) could work to decrease the rate at which nitrous oxide is

produced by adding different compounds that inhibit its synthesis (ABARES, n.d.). Methane is

another greenhouse gas, which is 21 times as potent as carbon dioxide (Boadi et al. 2004).

Methane is formed in the digestive tract of cattle by microbial processes and is eventually

released to the atmosphere (Boadi et al. 2004). Boadi et al. (2004) explain how feeding cattle

grain-based diets vs. roughage-based diets will both increase their productivity and decrease their

methane emissions. However, the increase in nitrogen fertilizer that is essential for growing the

food grain will contribute to both nitrous oxide and carbon dioxide emissions (Boadi et al. 2004).

Therefore, the overall greenhouse gas emissions impact must be evaluated. Currently, livestock

production accounts for 42% of agricultural greenhouse gas emissions (Boadi et al. 2004).

These are some of many ways that the agricultural industry contributes to greenhouse gas

emissions and therefore to global warming.

3.1.2 Impacts of Global Warming on Agriculture

These emissions will cause a subsequent warming due to the greenhouse effect, which in

turn negatively impacts the agricultural industry. For example, as stated previously, global

warming will result in changes in the ranges of different species. Currently, there is more

evidence for an increase in range due to climate warming than a decrease (Dawson et al. 2011).

This applies to many different pests, including the soybean aphid, which is native to Asia

(Heimpel et al. 2013). This aphid has become one of the biggest soybean pests in North America

(Heimpel et al. 2013). It is estimated that the manufacture, transport, and application of

insecticides against soybean aphid results in approximately 10.6 kg of carbon dioxide equivalent

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greenhouse gasses being emitted per hectare of soybeans treated (Heimpel et al. 2013). The

spread of crop pests will result in a positive feedback to climate warming. Different control

methods are being investigated such as crop-resistance as well as importing biological control

agents from Asia. Heimpel et al. (2013) found that if a pesticide threshold was implemented in

coalition with using biological control agents, the GHG emissions could be reduced by about 207

million kg of carbon dioxide equivalent gasses per year.

There are many agricultural implications of a warming climate and as a result our food

system is at risk. As shown with wild populations, crops will also experience a decrease in

available suitable habitat. Increasing temperatures have been shown to negatively correlate with

crop yields. A study by Tao et al. (2006) shows an increase in rice sterility with an increase in

the maximum temperature (Figure 12a) and a decrease in maize yields with a decrease in diurnal

temperature range, which results with greater night-time temperatures (Figure 12b). These

studies were both done in research stations in China. It is speculated by Tao et al. (2006) that

higher temperatures will increase the rate of phenological development to the extent that yields

are negatively impacted. In contrast, crop yields are benefiting from the rising atmospheric

carbon dioxide levels (Tao et al. 2006). As carbon dioxide is a necessary component of

photosynthesis, which is required for plant growth, an increase in this gas will result in what is

often referred to as carbon dioxide fertilization. Further research is necessary to elucidate the

overall impact of higher carbon dioxide levels and higher temperatures on crop yield. Under our

integration with Team Biotech we will be discussing ways in which we can aid in the sensitivity

and adaptive capacity of these crops in a changing climate.

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a) b) Figure 12. a) Relationship between rice spikelet sterility and the mean maximum temperature during the 20 days before

and after anthesis. b) Relationship between maize yield and mean diurnal temperature in summer (Tao et al. 2006).

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Integration with:

Youre Infected

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3.2 Impacts of Climate Change on Human Health

3.2.1 Disease Vectors

Climate Change is having a large impact on human health all over the globe. One of the

specific instances of this impact is the increasing prevalence of Lyme disease in Canada. Lyme

disease is transferred to humans through the bite of an infected deer tick. The specific bacterium

that causes this disease is Borrelia burgdorferi (Chief Medical Officer of Health, 2010). When a

tick inserts its head into the host skin it will start to feed on the blood of the host. Through this

attachment, it is able to pass on the Lyme disease bacteria after feeding for a minimum of 24

hours (Chief Medical Officer of Health, 2010).

Ticks live in the dead leaves that cover the forest floor and any other ground coverage

(Bradford & Hunka, 2013). When they are young, they feed on mice and other forest animals,

which is where they contract the bacterium that causes Lyme disease. In the past, most of the

deer ticks would die in the winter months since they are not able to survive in conditions lower

than 4C (Chief Medical Officer of Health, 2010). However, due to climate change, there are

now more ticks surviving the winter months and into the following spring than before. In

addition to this, songbirds returning from their wintering grounds in the south bring more ticks

every year into Canada (Bradford & Hunka, 2013). Although ticks are only able to travel a few

meters per year due to their size, they are expanding at a rate of nearly 46-50km per year

northward (Bradford & Hunka, 2013). This is due to the help that they are receiving from both

songbirds and the White-Footed mouse. The White-Footed mouse is known for carrying the

Lyme disease bacteria. As climate change expands their range, it is also leading to a correlated

increase with the deer tick (Bradford & Hunka, 2013). The current trajectory of this species is

expanding 10 kilometers per year northward and it is expected, by the year 2050, the White-

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footed mouse will populate nearly the entire province of Quebec (Bradford & Hunka, 2013).

This means that the deer ticks, as well, will populate the whole of Quebec.

The expansion of the deer tick in Canada has been quite rapid. In 1989, the only

established deer tick population was in the Long Point region of southern Ontario (Bradford &

Hunka, 2013). However in 2002 deer ticks were being observed all over the country. They

started appearing in the Maritimes followed by Quebec, Ontario, Manitoba and even British

Columbia (Bradford & Hunka, 2013). Their ability to colonize any environment suitable for their

biology has helped them to expand at such a rapid rate (Bradford & Hunka, 2013). Currently

their expansion is taking them through the most densely populated areas of Canada and by 2020

it is predicted that 80% of Canadians will be exposed to deer ticks (Bradford & Hunka, 2013).

This greatly increases the risk for Canadians to contract Lyme disease. Therefore, due to climate

change, the Canadian population is facing a new health threat as a direct result of climate change.

3.2.2 Heat Waves

Due to climate change and the warming planet, heat waves have been steadily rising in

the past decades. Heat waves are of biggest concern to the elderly and younger population,

whom are most susceptible to the negative effects of extreme temperatures. This is generally

caused by elderly people having pre-existing medical conditions that put them at higher risk.

Also, elderly people are generally considered to be less able to moderate their internal

temperature, which further increases their risk of death from heat waves (McMichael et al. 2006).

An example of the disastrous effects that heat waves can have on human health came in August

2003 in France when 14,802 people died in a heat wave (Haines et al. 2006). During heat waves,

the most severely affected places are city centers due to urban heat island effects (Haines et al.

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2006). Heat islands in city centers cause the centers of cities to be warmer than the surrounding

regions and this is why the effects are larger in city centers (Haines et al. 2006).

3.2.3 Natural Disasters

With the increasing prevalence of climate change, there is a correlated increase in climate

related natural disasters. These natural disasters often have a direct effect on the health of

humans living in the areas affected. These effects are further increased in third world countries

where their infrastructure is not properly designed and therefore, are not capable of appropriately

dealing with the natural disasters. The disasters that have the most impact on human health are

floods and hurricanes.

3.2.3.1 Floods

Floods are impacting humans by not only physically destroying cities and home, but also

adversely affecting human health. These impacts can be both short- and long-term. Short-term

health impacts are generally in the form of physical injuries sustained from flood debris or death

(Haines et al. 2006). Long-term health effects sustained from flooding often include mental

health issues that result from the actual flooding event (Haines et al. 2006). Here, the focus will

be on the short term health effects that people suffer from flood events. An example of a flood

event that significantly impacted human health was in 2002 in Dresden, Germany. This flood left

people without electricity and clean drinking water for nearly a week (Haines et al. 2006). After

flood events there is an increase in reported diarrhea and respiratory illnesses (Haines et al.

2006). Although this is a concern in developed countries, the effects in third world countries are

more severe. In these countries, access to proper medical treatments for the health concern is

usually lacking. Thus, the mortality rate from floods is increased due to decreased access to

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proper healthcare (Haines et al. 2006). Contrary to this, in countries that have increased access to

healthcare like those in North America and Europe these common illnesses rarely result in

death during flooding events. Thus the set-up of a countries medical system prior to a flooding

event will greatly affect the human health toll after the event has occurred.

3.2.3.2 Hurricanes

Hurricanes are very publicized and talked about events in the media, mainly due to the

great impact on the health of people affected by them. One of the most famous is hurricane

Katrinam, which impacted the United States on August 29, 2005. This hurricane in particular had

drastic effects on infrastructure in the areas that it decimated. The increased water levels created

breeding grounds for mosquitoes, and led to increased mould levels and decreased availability of

drinking water (Frank, 2013). Due to the increase in habitat for mosquitoes, outbreaks of West

Nile virus became a large concern for human health in the New Orleans area (Frank, 2013). In

other areas of the world, these increases in mosquito breeding grounds could cause increases in

even more severe diseases such as Malaria. Thus, due to a hurricanes ability to severely destroy

infrastructure, they pose large threats to human life and human health. With climate related

natural disasters expected to increase in the future, these effects on human health are likely to

increase.

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Integration with:

Waste Not Want Not

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3.3 Effect of Floods on the Spread of Contaminants

As discussed, an increase in rainfall intensity has been predicted as a result of climate

change (Schiermeier, 2011). This increase in rainfall has led to increased flooding in many

regions of the world. In particular, mountainous areas, which are inhabited by nearly a billion

people worldwide and cover one quarter of the Earths land surface, are at increased risk

(Allamano et al. 2009). Since water runs downhill in many of these mountainous landscapes,

people living in these areas are at an increased risk for flooding due to pooling of water in the

low-lying valleys (Allamano et al. 2009). In some areas of the world, it is predicted that an

increase in greenhouse gases will also cause an increase monsoon precipitation (Monirul Qader

Mirza, 2002). With a larger flood volume, bodies of water may experience overflow, and it may

take extended periods of time before the water is able to return to s