![Page 1: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/1.jpg)
Multiple Stressors
![Page 2: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/2.jpg)
Multiple Stressors
• Nutrient loading (nitrogen, phosphorous) or eutrophication
• UV light (UVB)• Contaminants (toxins, sediments)• Global warming (increased SST)• Atmospheric CO2 (plant growth)• Hypoxia, anoxia (dead zones)• Introduced species• Many more…
![Page 3: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/3.jpg)
Multiple Stressors
• Attempts to measure impacts of multiple stressors are fairly recent
• Only a limited number of habitats or species have been the subject of studies of multiple stressors
• Information usually incomplete and address pairs or small number of risks
• Many studies on temperature, contaminants, and nutrients, others less well studied
• Impacts on populations or habitats of most conservation interest poorly represented
![Page 4: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/4.jpg)
Rocky Shores
• A few studies on temperate rocky shores have looked at multiple stressors
• One conducted in Australia (Przeslawski et al. 2005) looked at the effects of UV radiation together with temperature and salinity stress
• They found significant effects of UV (12 fold higher mortality)
• Effects of salinity in the presence of UV were much more negative
![Page 5: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/5.jpg)
Przeslawski et al. 2005
![Page 6: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/6.jpg)
Przeslawski et al. 2005
![Page 7: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/7.jpg)
Antarctic Habitats
• Lenihan et al. (2003) conducted multiple stressor experiments on Antarctic benthos
• They used total organic carbon and copper as stressors in field experiments
• They found interacting effects which varied by taxa
• Annelids increased with TOC across Cu treatments
• Arthropods and echinoderms decreased with Cu but responded variably to TOC depending on feeding mode
![Page 8: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/8.jpg)
Lenihan et al. 2003
![Page 9: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/9.jpg)
Lenihan et al. 2003
![Page 10: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/10.jpg)
Lenihan et al. 2003
![Page 11: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/11.jpg)
Coral Reefs
• Nordemar et al. (2003) exposed corals (Porites) to nutrient and temperature stresses
• They exposed corals in mesocosms to combinations of nitrogen additions and temperature increases
• They found changes in gross productivity although specific effects on the zooxanthellae were less
![Page 12: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/12.jpg)
Nordemar et al. 2003
![Page 13: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/13.jpg)
Nordemar et al. 2003
![Page 14: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/14.jpg)
Coral Reefs
• Bruno et al. (2003) looked at nutrient addition and the outbreak of yellow band disease of corals in Mexico
• They added nutrients (nitrogen) in the field and monitored the progression of yellow band disease
• The found strong effects of nutrients on tissue loss and disease
![Page 15: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/15.jpg)
Bruno et al. 2003
![Page 16: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/16.jpg)
Bruno et al. 2003
![Page 17: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/17.jpg)
Coral Reefs
• Dunn and Brown (2001) followed coral bleaching in Thailand
• They compared severity of bleaching with temperature and UV records (together with sea surface)
• They found that bleaching occurred not just in response to temperature but much more strongly following exposure to solar radiation
![Page 18: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/18.jpg)
Dunne and Brown 2001
![Page 19: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/19.jpg)
Dunne and Brown 2001
![Page 20: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/20.jpg)
Dunne and Brown 2001
![Page 21: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/21.jpg)
Dunne and Brown 2001
![Page 22: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/22.jpg)
Dunne and Brown 2001
![Page 23: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/23.jpg)
Dunne and Brown 2001
![Page 24: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/24.jpg)
Coral Reefs
• Porter et al. 1999 looked at temperature and salinity stress in FL corals
• They found significant interactions and magnification of temperature stress at higher salinities
![Page 25: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/25.jpg)
Porter et al 1999
![Page 26: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/26.jpg)
![Page 27: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/27.jpg)
Porter et al 1999
![Page 28: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/28.jpg)
Porter et al 1999
![Page 29: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/29.jpg)
Porter et al 1999
![Page 30: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/30.jpg)
Algal Responses
• Hoffman et al. (2003) conducted experiments to look at temperature and UV in algae
• They used Fucus in the northwest and subjected this experimentally to UV and temperature at the same time
• First studies to experimentally manipulate temperature and UV in a multicellular organism
• They found very large difference among taxa and a strong interaction among stressors
![Page 31: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/31.jpg)
Hoffman et al. 2003
![Page 32: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/32.jpg)
Hoffman et al. 2003
![Page 33: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/33.jpg)
![Page 34: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/34.jpg)
Vinebrook et al. 2004
![Page 35: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/35.jpg)
Estuarine Stressors
• Estuaries are among the places where multiple stressors have best been studied
• Many studies of effects of contaminants, but fewer looking at other stressors (salinity, temperature, nutrients)
![Page 36: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/36.jpg)
Estuarine Stressors
• Good examples from Chesapeake Bay, MD (many labs, many scientists)
• Experiment (Breitburg et al. 1999) looked at nutrients and trace metals on many aspects of Chesapeake food webs
• 20 L mesocosms were constructed – Nitrogen and phosphorous (nutrients)– A mixture of arsenic, cadmium, copper, nickel and zinc
(trace elements)• They found consistent effects of nutrients (higher in
most cases) but trace elements had variable and ofter negative effects
• These negative effects were also increased by nutrient additions (reversing nutrient effect)
![Page 37: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/37.jpg)
Breitburg et al. 1999
![Page 38: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/38.jpg)
Breitburg et al. 1999
![Page 39: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/39.jpg)
Breitburg et al. 1999
![Page 40: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/40.jpg)
Breitburg et al. 1999
![Page 41: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/41.jpg)
Breitburg et al. 1999
![Page 42: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/42.jpg)
Breitburg et al. 1999
![Page 43: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/43.jpg)
Breitburg et al. 1999
![Page 44: Multiple Stressors. Nutrient loading (nitrogen, phosphorous) or eutrophication UV light (UVB) Contaminants (toxins, sediments) Global warming (increased](https://reader035.vdocument.in/reader035/viewer/2022070402/56649f265503460f94c3dd22/html5/thumbnails/44.jpg)