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ECOSYSTEMAakansha

1216512101B. Arch, Semester - 2

GSA, Gitam University,Vishakhapatnam,Andhra Pradesh

AbstractAn environmental study is the interdisciplinary academic field which systematically studies human interaction with the environment in the interests of solving complex problems. It is a broad field of study that includes also the natural environment, built environment, and the sets of relationships between them. The field encompasses study in basic principles of ecology and environmental science, as well as associated subjects such as ethics, politics, law, economics, philosophy, environmental sociology and environmental justice, planning, pollution control and natural resource management.

Ecosystem & its conservation are one of the major topics of discussion among the environmentalists. Due to natural as well as human activities, it is getting degraded from years and if no precaution is taken for it, then it will not be sustaining for the future generations and might slowly lead to the depletion of the earth.

So, this report is to make all the people aware of about it, so that it will lead to public awareness and its conservation will become a world step and will prevent the ecosystem and biodiversity from being depleted.

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IntroductionThe purpose of this report is to identify different types of ecosystem and biodiversity and the types of threat it is facing and will be facing in future due to human activities as well as natural calamities

It also shows importance of ecosystem and biodiversity and the factors influencing them.It shows the effect of decline of ecosystem and biodiversity.Mainly this report highlights the different ways towards the conservation of ecosystem and biodiversity.

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CONTENTSSr No. TOPIC Pg No.

1. What is an ecosystem? 52. History and development 63. Geography of ecosystem 74. Types of ecosystem

i) Forest ecosystem……………………..ii) Desert ecosystem…………………….iii) Grassland ecosystem………………….iv) Aquatic ecosystem……………………

89,1011-131415-18

5. Ecosystem process 19-216. Nutrient cycle 21-237. Role of an ecosystem 248. Function and biodiversity 259. Ecosystem management 26,2710. Threats to ecosystem 28,2911. Ecosystem conservation 3012. conclusion 31

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What is an ecosystem?

An ecosystem is an area composed of abiotic and biotic factors. There are lots of kinds of ecosystems all around the world. An ecosystem consists of the biological community that occurs in some locale, and the physical and chemical factors that make up its non-living or abiotic environment. There are many examples of ecosystems -- a pond, a forest, an estuary, grassland. The boundaries are not fixed in any objective way, although sometimes they seem obvious, as with the shoreline of a small pond.Usually the boundaries of an ecosystem are chosen for practical reasons having to do with the goals of the particular study.

The study of ecosystems mainly consists of the study of certain processes that link the living, or biotic, components to the non-living, or abiotic, components. Energy transformations and biogeochemical cycling are the main processes that comprise the field of ecosystem ecology. 

Components of an EcosystemABIOTIC COMPONENTS BIOTIC COMPONENTS

Sunlight Primary producersTemperature HerbivoresPrecipitation CarnivoresWater or moisture OmnivoresSoil or water chemistry (e.g., P, NH4+) Detritivoresetc. etc.

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All of these vary over space/time

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History and development

Arthur Tansley, a British ecologist, was the first person to use the term "ecosystem" in a published work. Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment. He later refined the term, describing it as "The whole system, including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment". Tansley regarded ecosystems not simply as natural units, but as mental isolates. Tansley later defined the spatial extent of ecosystems using the term ecotope.

G. Evelyn Hutchinson, a pioneering limnologist who was a contemporary of Tansley's, combined Charles Elton's ideas about trophic ecology with those of Russian geochemist Vladimir Vernadsky to suggest that mineral nutrient availability in a lake limited algal production which would, in turn, limit the abundance of animals that feed on algae. Raymond Lindeman took these ideas one step further to suggest that the flow of energy through a lake was the primary driver of the ecosystem.

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Hutchinson's students, brothers Howard T. Odum and Eugene P. Odum, further developed a "systems approach" to the study of ecosystems, allowing them to study the flow of energy and material through ecological system.

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The Geography of Ecosystems

There are many different ecosystems: rain forests and tundra, coral reefs and ponds, grasslands and deserts. Climate differences from place to place largely determine the types of ecosystems we see. How terrestrial ecosystems appear to us is influenced mainly by the dominant vegetation.The word "biome" is used to describe a major vegetation type such as tropical rain forest, grassland, tundra, etc., extending over a large geographic area (Figure). It is never used for aquatic systems, such as ponds or coral reefs. It always refers to a vegetation category that is dominant over a very large geographic scale, and so is somewhat broader than an ecosystem.

Figure: The distribution of biomes.

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Types of ecosystem

1. Forest

2. Desert

3. Grassland

4. Freshwater

5. Marine water

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ForestEcosystem

Deciduous Forest

Tropical rain Forest

Coastal Forest

Coniferous Forest

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Deciduous forest:

Large, flat leaves that drop off in the fall, new leaves grow in spring. Leaves change color with the season. Trees grow at places with warm wet, summers and cold winters.

Tropical rain forest:

These trees grow at places which are hot and wet whole year. Trees are very tall and leaves are always green. The forest has three layers – canopy, understory & forest floor.

Coastal forest:

Grows in places where there is lots of rain. Temperature is neither too hot nor too cold. Have three layers just like rain forest – canopy, understory & forest

floor.

Coniferous forest:

Grows in places with very cold winters and hot summers. The leaves look like needles, so they don’t need much water. Seeds grow in cones. Gets less rain than all the other forests.

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LocationHot deserts.Cold deserts.

PlantsDon’t need much water.Have special parts to beat heat.

AnimalsHave hard shell to protect from water loss.

ClimateVery dry &

warm.Little rain per year.

DESERT Ecosystem

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CLIMATE:

The desert is very dry and warm. Rainfall is very less per year. Some deserts cross 100F of temperature.

LOCATION:

Hot desert: Temperature is very high all the year. Summers are very hot. Example: Arabian Peninsula, great sandy Victoria, Thar,

Sahara, etc.

Cold desert: Short and warm summers. Long and cold winters. Located in North Pole and South Pole. Example: takla makan, Atacama, gobi, great basin, Turkestan,

etc

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ANIMALS: Protect them from the heat by staying under some shelter or shade. They survive by eating other animals or by eating plants that store

water in them. Some animals sleep during daytime and become active at night. Some animals have hard shells to protect them from loosing much

water especially by heat. More animals live in hot deserts than in cold deserts. Example: anteater, camel, roadrunner, scorpion, Gila monster

(lizard), etc.

Anteater Camel Roadrunner Gila monster

PLANTS: Many plants growing in deserts grow close to the ground for easy

access to water. They have special parts that help them in saving water. The special parts are: thick stems, shallow and wide roots and thick

skin covered with spines instead of leaves. Examples: cactus, babul, crucifixion bush, desert willow, Joshua

trees, etc.

Cactus Babul Crucifixion Willow Joshua

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TROPICAL GRASSLAND: Found in areas with high average temperature, low to precipitation

and a prolonged dry season. They are widely spread on either side of the equator. Savanna is a great example of tropical grassland.

TEMPERATE GRASSLAND: Cover vast expanses of plains and gently rolling hills in the interior

of north and South America, Europe and Asia. Winters are bitterly cold, summers are hot and dry and annual

precipitation falls unevenly throughout the year.

POLAR GRASSLAND: (Tundra) A cold, treeless, usually lowland area of far northern region. The lower strata of soil of tundra are permanently frozen, but in

summer the top layer of the soil thaws and can support low-growing mosses, lichens, grasses and small shrubs.

GRASSLAND

Tropical Temperate Polar(Tundra)

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MARINEShorelineBarrier islandCoral reefsOpen ocean

TRANSITIONAL

COMMUNITOES

EstuariesWet lands

FRESHWATER

Standing waterMoving water

AQUATIC ECOSYSTE

M

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Freshwater ecosystem

Rivers, ponds, lakes and streams have fresh water. for some rivers. Important rivers, most often, originate from

lakes. Some rivers end in lakes. Since both rivers and lakes are freshwater and flow in and

out of each other, they share similar characteristics and many species reside in both habitats.

Usually 0.005% salt present with some exceptional ones like great salt lakes – 5 to 27% of salt & dead sea with 30% of salt.

Moving water are cold and high in oxygen amount. Standing water are warmer and less in oxygen amount.

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Transitional communitiesEstuaries:

Place where freshwater dumps into ocean. Brackish (less salty than sea water). Have rich sediments that often form deltas.

Wetlands: SWAMPS - have trees like bald cypress; high

productivity. MARSHES – have no trees and consist of only tall

grasses with high productivity. BOGS/FENS – it may or may not have trees. waterlogged

soils with lots of peat but have low productivity.

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Marine ecosystem

Shorelines: Rocky coasts: it has great density and diversity attached to

the solid surface. Sandy beaches; this consists of burrowing animals. Threats: threats are caused to them due to hotels,

restaurants, houses near beaches and so plant life gets destroyed, destabilizing of soil, susceptible to wind and water erosion takes place.

Barrier Island: They are low and narrow offshore islands. It protects inland shores from shores. New coastal zoning law has been made to protect future

development.

Coral reefs: They are found in clear, warm shallow seas. It’s made up of accumulated calcareous skeletons of coral

animals. It has symbiotic relation with algae. Its formation depends on the amount of light penetration. They are dense and are in abundance.

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ECOSYSTEM PROCESSES:

Energy and carbon enter ecosystems through photosynthesis, are incorporated into living tissue, transferred to other organisms that feed on the living and dead plant matter, and eventually released through respiration. Most mineral nutrients, on the other hand, are recycled within ecosystems.

Ecosystems are controlled both by external and internal factors. External factors, also called state factors, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem. The most important of these is climate.

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Climate determines the biome in which the ecosystem is embedded. Rainfall patterns and temperature seasonality determine the amount of water available to the ecosystem and the supply of energy available (by influencing photosynthesis).Parent material, the underlying geological material that gives rise to soils, determines the nature of the soils present, and influences the supply of mineral nutrients. Topography also controls ecosystem processes by affecting things like microclimate, soil development and the movement of water through a system. This may be the difference between the ecosystem present in wetland situated in a small depression on the landscape, and one present on an adjacent steep hillside.Other external factors that play an important role in ecosystem functioning include time and potential biota. Ecosystems are dynamic entities—invariably, they are subject to periodic disturbances and are in the process of recovering from some past disturbance. Time plays a role in the development of soil from bare rock and the recovery of a community from disturbance. Similarly, the set of organisms that can potentially be present in an area can also have a major impact on ecosystems. Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.Unlike external factors, internal factors in ecosystems not only control ecosystem processes, but are also controlled by them. While the resource inputs are generally controlled by external processes like climate and parent material, the availability of these resources within the ecosystem is controlled by internal factors like decomposition, root competition or shading. Other factors like

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disturbance, succession or the types of species present are also internal factors. Although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.

Nutrient cycle:

Ecosystems continually exchange energy and carbon with the wider environment; mineral nutrients, on the other hand, are mostly cycled back and forth between plants, animals, microbes and the

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soil. Most nitrogen enters ecosystems through biological nitrogen fixation, is deposited through precipitation, dust, gases or is applied as fertilizer. Since most terrestrial ecosystems are nitrogen-limited, nitrogen cycling is an important control on ecosystem production.Until modern times, nitrogen fixation was the major source of nitrogen for ecosystems. Nitrogen fixing bacteria either live symbiotically with plants, or live freely in the soil. The energetic cost is high for plants which support nitrogen-fixing symbionts—as much as 25% of GPP when measured in controlled conditions.

Many members of the legume plant family support nitrogen-fixing symbionts. Some cyanobacteria are also capable of nitrogen fixation. These arephototrophs, which carry out photosynthesis. Like other nitrogen-fixing bacteria, they can either be free-living or have symbiotic relationships with plants. Other sources of nitrogen include acid deposition produced through the combustion of fossil fuels, ammonia gas which evaporates from agricultural fields which have had fertilizers applied to them, and dust. Anthropogenic nitrogen inputs account for about 80% of all nitrogen fluxes in ecosystems. When plant tissues are shed or are eaten, the nitrogen in those tissues becomes available to animals and microbes. Microbial decomposition releases nitrogen compounds from dead organic matter in the soil, where plants, fungi and bacteria compete for it. Some soil bacteria use organic nitrogen-containing compounds as a source of carbon, and release ammonium ions into the soil. This process is known as nitrogen mineralization. Others convert ammonium to nitrite and nitrate ions, a process known as nitrification. Nitric oxide and nitrous oxide are also produced during nitrification. Under nitrogen-rich and oxygen-poor

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conditions, nitrates and nitrites are converted to nitrogen gas, a process known as denitrification. Other important nutrients include phosphorus, sulfur, calcium, potassium, magnesium and manganese. Phosphorus enters ecosystems through weathering. As ecosystems age this supply diminishes, making phosphorus-limitation more common in older landscapes (especially in the tropics). Calcium and sulfur are also produced by weathering, but acid deposition is an important source of sulfur in many ecosystems. Although magnesium and manganese are produced by weathering, exchanges between soil organic matter and living cells account for a significant portion of ecosystem fluxes. Potassium is primarily cycled between living cells and soil organic matter.

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ROLE OF AN ECOSYSTEM Ecosystem services are ecologically mediated functional

processes essential to sustaining healthy human societies.

Water provision and filtration, production of biomass in forestry, agriculture, and fisheries, and removal of greenhouse gases such as carbon dioxide (CO2) from the atmosphere are examples of ecosystem services essential to public health and economic opportunity.

Nutrient cycling is a process fundamental to agricultural and forest production.

Ecosystem goods include the "tangible, material products"  of ecosystem processes—food, construction material, medicinal plants—in addition to less tangible items like tourism and recreation, and genes from wild plants and animals that can be used to improve domestic species.  

Ecosystem services, on the other hand, are generally "improvements in the condition or location of things of value". These include things like the maintenance of hydrological cycles, cleaning air and water, the maintenance of oxygen in the atmosphere, crop pollination and even things like beauty, inspiration and opportunities for research.

 While ecosystem goods have traditionally been recognized as being the basis for things of economic value, ecosystem services tend to be taken for granted.  

 Gretchen Daily's original definition distinguished between ecosystem goods and ecosystem services, Robert Costanza and colleagues' later work and that of the Millennium Ecosystem Assessment lumped all of these together as ecosystem services.

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Function and biodiversity

Ecosystem processes are broad generalizations that actually take place through the actions of individual organisms. The nature of the organisms—the species, functional groups and trophic levels to which they belong—dictates the sorts of actions these individuals are capable of carrying out, and the relative efficiency with which they do so. Thus, ecosystem processes are driven by the number of species in an ecosystem, the exact nature of each individual species, and the relative abundance organisms within these species.  Biodiversity plays an important role in ecosystem functioning.

Ecological theory suggests that in order to coexist, species must have some level of limiting similarity—they must be different from one another in some fundamental way, otherwise one species would competitively exclude the other.  Despite this, the cumulative effect of additional species in an ecosystem is not linear—additional species may enhance nitrogen retention, for example, but beyond some level of species richness, additional species may have little additive effect.  The addition (or loss) of species which are ecologically similar to those already present in an ecosystem tends to only have a small effect on ecosystem function. Ecologically distinct species, on the other hand, have a much larger effect. Similarly, dominant species have a large impact on ecosystem function, while rare species tend to have a small effect. Keystone species tend to have an effect on ecosystem function that is disproportionate to their abundance in an ecosystem.

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Ecosystem management

When natural resource management is applied to whole ecosystems, rather than single species, it is termed ecosystem management.

 A variety of definitions exist: F. Stuart Chapin and coauthors define it as "the application of ecological science to resource management to promote long-term sustainability of ecosystems and the delivery of essential ecosystem goods and services",  while Norman Christensen and coauthors defined it as "management driven by explicit goals, executed by policies, protocols, and practices, and made adaptable by monitoring and research based on our best understanding of the ecological interactions and processes necessary to sustain ecosystem structure and function" and Peter Brussard and colleagues defined it as "managing areas at various scales in such a way that ecosystem services and biological resources are preserved while appropriate human use and options for livelihood are sustained".Although definitions of ecosystem management abound, there is a common set of principles which underlie these definitions.  A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem; "intergenerational sustainability [is] a precondition for management, not an afterthought". It also requires clear goals with respect to future trajectories and behaviors of the system being managed. Other important requirements include a sound ecological understanding of the system, including connectedness, ecological dynamics and the context in which the system is embedded.Other important principles include an understanding of the role of humans as components of the ecosystems and the use of adaptive management.

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 While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems  (for example, agro ecosystem and close to nature forestry).

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Threats to ecosystem

There are generally considered to be nine major threats to the stability of ecosystems on Earth. Climate change and loss of biodiversity are often the most

publicized, although there are seven other factors that may be equally threatening.

The spread of agriculture and other human activities into natural habitats poses a large threat to ecosystems.

The disruption of fresh water systems through damming and diversion by humans can lead to vast habitats becoming dry and barren.

Chemical pollution can have devastating effects of the health of ecosystems (as well as humans) and the release of aerosols into the atmosphere (through activities such as burning fossil fuels) damages ecosystems in numerous ways. The release of aerosols (among other things) can also lead to the depletion of the ozone layer which threatens to allow harmful solar radiation to cause damage to organisms and ecosystems.

Another potential threat to global ecosystems that is rarely discussed is the acidification of the oceans due to increased carbon dioxide in the atmosphere, which can have serious knock-on effects on important aspects of ocean chemistry.

The disruption of the nitrogen cycle can lead to bacteria converting too much nitrogen from the atmosphere into a form not readily available for living things (this is often encouraged by agriculture to give higher crop yields).

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Of course, many of these threats are interlinked and if one threat were to go unchecked and get out of control, others will likely follow suit.

Climate change, disruption of the nitrogen cycle and the rate of biodiversity loss were considered to pose the most imminent threats to ecosystems on Earth, although others were not far behind.

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Ecosystem conservation

The main function of ecosystem conservation is protecting or restoring the structure, function and species compilation within the system. This can get hard quickly, because everything in an ecosystem affects everything else.

The best way to conserve an ecosystem is to approach it from a large-scale view. Large-scale approaches avoid the pitfalls of species-by-species methods that can drain finances and resources fast. These methods also become one giant headache because the conservationists become stuck in an environmental loop, always trying to come up with something new to fix the problem they just introduced.

It is important for the conservationists to work with the local people and governments so that there can be conservation goals that work well within the ecological unit and with the needs of the people.

Whether an ecosystem will fail or not depends on the toxicity of new factors, the resiliency of the ecosystem and its ability to adapt. A toxic factor will ruin an ecosystem, but a resilient ecosystem will be able to handle the change.

For ecosystem conservation, it is important to note that they function best when left alone. Results of too much human intervention can be disastrous.

The best approach to conservation is through goals that work with the ecosystem and the human sides of things. This ensures the preservation of wild ecosystems, as well as allowing people to live freely within them.

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Conclusion

Everyone in the world depends completely on Earth’s ecosystems and the services they provide, such as food, water, disease management, climate regulation, spiritual fulfillment, and aesthetic enjoyment. Over the past 50 years, humans have changed these ecosystems more rapidly and extensively than in any comparable period of time in human history, largely to meet rapidly growing demands for food, fresh water, timber, fiber, and fuel. This transformation of the planet has contributed to substantial net gains in human well-being and economic development. But not all regions and groups of people have benefited from this process—in fact, many have been harmed. Moreover, the full costs associated with these gains are only now becoming apparent. So it is better that care for ecosystem should be taken as one of the major responsibility of every individual for sustainable living of future generations as well.

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