Earth:Productivity (ecology)

From HandWiki
Short description: Rate of generation of biomass in an ecosystem

In ecology, the term productivity refers to the rate of generation of biomass in an ecosystem, usually expressed in units of mass per volume (unit surface) per unit of time, such as grams per square metre per day (g m−2 d−1). The unit of mass can relate to dry matter or to the mass of generated carbon. The productivity of autotrophs, such as plants, is called primary productivity, while the productivity of heterotrophs, such as animals, is called secondary productivity.[1]

The productivity of an ecosystem is influenced by a wide range of factors, including nutrient availability, temperature, and water availability. Understanding ecological productivity is vital because it provides insights into how ecosystems function and the extent to which they can support life.[2] Productivity is typically divided into two categories: primary and secondary productivity.

Primary production

Main page: Earth:Primary production

Primary production is the synthesis of organic material from inorganic molecules. Primary production in most ecosystems is dominated by the process of photosynthesis, In which organisms synthesize organic molecules from sunlight, H2O, and CO2.[3] Aquatic primary productivity refers to the production of organic matter, such as phytoplankton, aquatic plants, and algae, in aquatic ecosystems, which include oceans, lakes, and rivers. Terrestrial primary productivity refers to the organic matter production that takes place in terrestrial ecosystems such as forests, grasslands, and wetlands.

Primary production is divided into Net Primary Production (NPP) and Gross Primary Production (GPP). Gross primary production measures all carbon assimilated into organic molecules by primary producers.[4] Net primary production measures the organic molecules by primary producers. Net primary production also measures the amount of carbon assimilated into organic molecules by primary producers, but does not include organic molecules that are then broken down again by these organism for biological processes such as cellular respiration.[5] The formula used to calculate NPP is net primary production = gross primary production - respiration.

Primary producers

Photoautotrophs

Organisms that rely on light energy to fix carbon, and thus participate in primary production, are referred to as photoautotrophs.[6]

Photoautotrophs exists across the tree of life. Many bacterial taxa are known to be photoautotrophic such as cyanobacteria[7] and some Pseudomonadota (formerly proteobacteria).[8] Eukaryotic organisms gained the ability to participate in photosynthesis through the development of plastids derived from endosymbiotic relationships.[9] Archaeplastida, which includes red algae, green algae, and plants, have evolved chloroplasts originating from an ancient endosymbiotic relationship with an Alphaproteobacteria.[10] The productivity of plants, while being photoautotrophs, is also dependent on factors such as salinity and abiotic stressors from the surrounding environment.[11] The rest of the eukaryotic photoautotrophic organisms are within the SAR clade (Comprising Stramenopila, Alveolata, and Rhizaria). Organisms in the SAR clade that developed plastids did so through a secondary or a tertiary endosymbiotic relationships with green algae and/or red algae.[12] The SAR clade includes many aquatic and marine primary producers such as Kelp, Diatoms, and Dinoflagellates.[12]

Lithoautotrophs

The other process of primary production is lithoautotrophy. Lithoautotrophs use reduced chemical compounds such as hydrogen gas, hydrogen sulfide, methane, or ferrous ion to fix carbon and participate in primary production. Lithoautotrophic organisms are prokaryotic and are represented by members of both the bacterial and archaeal domains.[13] Lithoautotrophy is the only form of primary production possible in ecosystems without light such as ground-water ecosystems,[14] hydrothermal vent ecosystems,[15] soil ecosystems,[16] and cave ecosystems.[17]

Secondary production

Secondary production is the generation of biomass of heterotrophic (consumer) organisms in a system. This is driven by the transfer of organic material between trophic levels, and represents the quantity of new tissue created through the use of assimilated food. Secondary production is sometimes defined to only include consumption of primary producers by herbivorous consumers[18] (with tertiary production referring to carnivorous consumers),[19] but is more commonly defined to include all biomass generation by heterotrophs.[1]

Organisms responsible for secondary production include animals, protists, fungi and many bacteria.[citation needed]

Secondary production can be estimated through a number of different methods including increment summation, removal summation, the instantaneous growth method and the Allen curve method.[20] The choice between these methods will depend on the assumptions of each and the ecosystem under study. For instance, whether cohorts should be distinguished, whether linear mortality can be assumed and whether population growth is exponential.[citation needed]

Net ecosystem production is defined as the difference between gross primary production (GPP) and ecosystem respiration.[21] The formula to calculate net ecosystem production is NEP = GPP - respiration (by autotrophs) - respiration (by heterotrophs).[22] The key difference between NPP and NEP is that NPP focuses primarily on autotrophic production, whereas NEP incorporates the contributions of other aspects of the ecosystem to the total carbon budget.[23]

Productivity

Following is the list of ecosystems in order of decreasing productivity. [citation needed]

Producer Biomass productivity (gC/m²/yr)
Swamps and Marshes 2,500
Coral reefs 2,000
Algal beds 2,000
River estuaries 1,800
Temperate forests 1,250
Cultivated lands 650
Tundras 140
Open ocean 125

Species diversity and productivity relationship

The connection between plant productivity and biodiversity is a significant topic in ecology, although it has been controversial for decades. Both productivity and species diversity are constricted by other variables such as climate, ecosystem type, and land use intensity.[24] According to some research on the correlation between plant diversity and ecosystem functioning is that productivity increases as species diversity increases.[25] One reasoning for this is that the likelihood of discovering a highly productive species increases as the number of species initially present in an ecosystem increases.[25][26]

Other researchers believe that the relationship between species diversity and productivity is unimodal within an ecosystem.[27] A 1999 study on grassland ecosystems in Europe, for example, found that increasing species diversity initially increased productivity but gradually leveled off at intermediate levels of diversity.[28] More recently, a meta-analysis of 44 studies from various ecosystem types observed that the interaction between diversity and production was unimodal in all but one study.[29]

Human interactions

Anthropogenic activities (human activities) have impacted the productivity and biomass of several ecosystems. Examples of these activities include habitat modification, freshwater consumption, an increase in nutrients due to fertilizers, and many others.[30] Increased nutrients can stimulate an algal bloom in waterbodies, increasing primary production but making the ecosystem less stable.[31] This would raise secondary production and have a trophic cascade effect across the food chain, ultimately increasing overall ecosystem productivity.[32]

See also

References

  1. ↑ 1.0 1.1 Allaby, Michael, ed (2006). A Dictionary of Ecology (Third ed.). Oxford, UK: Oxford University Press. ISBN 978-0-19-860905-6. http://www.oxfordreference.com/views/ENTRY.html?subview=Main&entry=t14.e4512. Retrieved 2009-12-03. 
  2. ↑ US EPA, ORD (2017-11-01). "Ecological Condition" (in en). https://www.epa.gov/report-environment/ecological-condition. 
  3. ↑ Johnson, Matthew P. (2016-10-26). "Photosynthesis". Essays in Biochemistry 60 (3): 255–273. doi:10.1042/EBC20160016. ISSN 0071-1365. PMID 27784776. PMC 5264509. https://doi.org/10.1042/EBC20160016. 
  4. ↑ Woodwell, George (1 August 2015). "Primary Production in Terrestrial Ecosystems". American Zoologist 8: 19–30. doi:10.1093/icb/8.1.19. 
  5. ↑ Yu, Bo; Chen, Fang (2016-08-02). "The global impact factors of net primary production in different land cover types from 2005 to 2011". SpringerPlus 5 (1): 1235. doi:10.1186/s40064-016-2910-1. ISSN 2193-1801. PMID 27536518. 
  6. ↑ Scognamiglio, Viviana; Giardi, Maria Teresa; Zappi, Daniele; Touloupakis, Eleftherios; Antonacci, Amina (January 2021). "Photoautotrophs–Bacteria Co-Cultures: Advances, Challenges and Applications" (in en). Materials 14 (11): 3027. doi:10.3390/ma14113027. ISSN 1996-1944. PMID 34199583. Bibcode: 2021Mate...14.3027S. 
  7. ↑ Singh, Jay Shankar; Kumar, Arun; Rai, Amar N.; Singh, Devendra P. (2016). "Cyanobacteria: A Precious Bio-resource in Agriculture, Ecosystem, and Environmental Sustainability". Frontiers in Microbiology 7: 529. doi:10.3389/fmicb.2016.00529. ISSN 1664-302X. PMID 27148218. 
  8. ↑ Tang, Kuo-Hsiang; Tang, Yinjie J.; Blankenship, Robert Eugene (2011). "Carbon Metabolic Pathways in Phototrophic Bacteria and Their Broader Evolutionary Implications" (in English). Frontiers in Microbiology 2: 165. doi:10.3389/fmicb.2011.00165. PMID 21866228. 
  9. ↑ Margulis, L. (1968-09-06). "Evolutionary criteria in thallophytes: a radical alternative". Science 161 (3845): 1020–1022. doi:10.1126/science.161.3845.1020. PMID 17812802. Bibcode: 1968Sci...161.1020M. 
  10. ↑ Ford Doolittle, W (1998-12-01). "You are what you eat: a gene transfer ratchet could account for bacterial genes in eukaryotic nuclear genomes" (in en). Trends in Genetics 14 (8): 307–311. doi:10.1016/S0168-9525(98)01494-2. PMID 9724962. 
  11. ↑ Harman, Gary; Khadka, Ram; Doni, Febri; Uphoff, Norman (2021). "Benefits to Plant Health and Productivity From Enhancing Plant Microbial Symbionts". Frontiers in Plant Science 11: 610065. doi:10.3389/fpls.2020.610065. ISSN 1664-462X. PMID 33912198. 
  12. ↑ 12.0 12.1 Grattepanche, Jean-David; Walker, Laura M.; Ott, Brittany M.; Paim Pinto, Daniela L.; Delwiche, Charles F.; Lane, Christopher E.; Katz, Laura A. (2018). "Microbial Diversity in the Eukaryotic SAR Clade: Illuminating the Darkness Between Morphology and Molecular Data". BioEssays 40 (4): e1700198. doi:10.1002/bies.201700198. PMID 29512175. 
  13. ↑ Lazar, Cassandre Sara; Stoll, Wenke; Lehmann, Robert; Herrmann, Martina; Schwab, Valérie F.; Akob, Denise M.; Nawaz, Ali; Wubet, Tesfaye et al. (2017-06-13). "Archaeal Diversity and CO2 Fixers in Carbonate-/Siliciclastic-Rock Groundwater Ecosystems". Archaea 2017: 1–13. doi:10.1155/2017/2136287. PMID 28694737. 
  14. ↑ Griebler, C.; Lueders, T. (2009). "Microbial biodiversity in groundwater ecosystems" (in en). Freshwater Biology 54 (4): 649–677. doi:10.1111/j.1365-2427.2008.02013.x. 
  15. ↑ Sievert, Stefan; Vetriani, Costantino (2012-03-01). "Chemoautotrophy at Deep-Sea Vents: Past, Present, and Future". Oceanography 25 (1): 218–233. doi:10.5670/oceanog.2012.21. 
  16. ↑ Drake, Henrik; Ivarsson, Magnus (2018-01-01). "The role of anaerobic fungi in fundamental biogeochemical cycles in the deep biosphere" (in en). Fungal Biology Reviews 32 (1): 20–25. doi:10.1016/j.fbr.2017.10.001. https://portal.findresearcher.sdu.dk/da/publications/49859f59-f2d6-4a06-a2f7-5108375c1f25. 
  17. ↑ Galassi, Diana M. P.; Fiasca, Barbara; Di Lorenzo, Tiziana; Montanari, Alessandro; Porfirio, Silvano; Fattorini, Simone (2017-03-01). "Groundwater biodiversity in a chemoautotrophic cave ecosystem: how geochemistry regulates microcrustacean community structure" (in en). Aquatic Ecology 51 (1): 75–90. doi:10.1007/s10452-016-9599-7. 
  18. ↑ "Definition of term: "Secondary production"". The Glossary Table. FishBase. http://filaman.ifm-geomar.de/Glossary/Glossary.php?q=secondary+production&language=english&sc=is. 
  19. ↑ "Definition of term: "Tertiary production"". The Glossary Table. FishBase. http://filaman.ifm-geomar.de/Glossary/Glossary.php?q=tertiary+production&language=english&sc=is. 
  20. ↑ Allen, K.R. (1951). "The Horokiwi Stream: A study of a trout population". New Zealand Marine Department Fisheries Bulletin 10: 1–238. 
  21. ↑ Lovett, Gary M.; Cole, Jonathan J.; Pace, Michael L. (2006-01-30). "Is Net Ecosystem Production Equal to Ecosystem Carbon Accumulation?" (in en). Ecosystems 9 (1): 152–155. doi:10.1007/s10021-005-0036-3. ISSN 1432-9840. http://link.springer.com/10.1007/s10021-005-0036-3. 
  22. ↑ "The Flow of Energy: Primary Production". https://www.globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/energyflow.html. 
  23. ↑ Randerson, J. T.; Chapin, F. S.; Harden, J. W.; Neff, J. C.; Harmon, M. E. (2002-08-01). [0937:NEPACM2.0.CO;2 "Net Ecosystem Production: A Comprehensive Measure of Net Carbon Accumulation by Ecosystems"] (in en). Ecological Applications 12 (4): 937–947. doi:10.1890/1051-0761(2002)012[0937:NEPACM2.0.CO;2]. ISSN 1051-0761. http://doi.wiley.com/10.1890/1051-0761(2002)012[0937:NEPACM]2.0.CO;2. 
  24. ↑ Brun, Philipp; Zimmermann, Niklaus E.; Graham, Catherine H.; Lavergne, Sébastien; Pellissier, Loïc; Münkemüller, Tamara; Thuiller, Wilfried (2019-12-12). "The productivity-biodiversity relationship varies across diversity dimensions" (in en). Nature Communications 10 (1): 5691. doi:10.1038/s41467-019-13678-1. ISSN 2041-1723. PMID 31831803. Bibcode: 2019NatCo..10.5691B. 
  25. ↑ 25.0 25.1 van Ruijven, Jasper; Berendse, Frank (2005-01-18). "Diversity–productivity relationships: Initial effects, long-term patterns, and underlying mechanisms" (in en). Proceedings of the National Academy of Sciences 102 (3): 695–700. doi:10.1073/pnas.0407524102. ISSN 0027-8424. PMID 15640357. Bibcode: 2005PNAS..102..695V. 
  26. ↑ Waide, R. B.; Willig, M. R.; Steiner, C. F.; Mittelbach, G.; Gough, L.; Dodson, S. I.; Juday, G. P.; Parmenter, R. (November 1999). "The Relationship Between Productivity and Species Richness" (in en). Annual Review of Ecology and Systematics 30 (1): 257–300. doi:10.1146/annurev.ecolsys.30.1.257. ISSN 0066-4162. https://www.annualreviews.org/doi/10.1146/annurev.ecolsys.30.1.257. 
  27. ↑ Fraser, Lauchlan H.; Pither, Jason; Jentsch, Anke; Sternberg, Marcelo; Zobel, Martin; Askarizadeh, Diana; Bartha, Sandor; Beierkuhnlein, Carl et al. (2015). "Worldwide evidence of a unimodal relationship between productivity and plant species richness". Science 349 (6245): 302–305. doi:10.1126/science.aab3916. ISSN 0036-8075. PMID 26185249. Bibcode: 2015Sci...349..302F. https://www.jstor.org/stable/24748582. 
  28. ↑ Hector, A.; Schmid, B.; Beierkuhnlein, C.; Caldeira, M. C.; Diemer, M.; Dimitrakopoulos, P. G.; Finn, J. A.; Freitas, H. et al. (1999-11-05). "Plant Diversity and Productivity Experiments in European Grasslands" (in en). Science 286 (5442): 1123–1127. doi:10.1126/science.286.5442.1123. ISSN 0036-8075. PMID 10550043. https://www.science.org/doi/10.1126/science.286.5442.1123. 
  29. ↑ Cardinale, Bradley J.; Wright, Justin P.; Cadotte, Marc W.; Carroll, Ian T.; Hector, Andy; Srivastava, Diane S.; Loreau, Michel; Weis, Jerome J. (2007-11-13). "Impacts of plant diversity on biomass production increase through time because of species complementarity" (in en). Proceedings of the National Academy of Sciences 104 (46): 18123–18128. doi:10.1073/pnas.0709069104. ISSN 0027-8424. PMID 17991772. Bibcode: 2007PNAS..10418123C. 
  30. ↑ Isbell, Forest; Reich, Peter B.; Tilman, David; Hobbie, Sarah E.; Polasky, Stephen; Binder, Seth (2013-07-16). "Nutrient enrichment, biodiversity loss, and consequent declines in ecosystem productivity" (in en). Proceedings of the National Academy of Sciences 110 (29): 11911–11916. doi:10.1073/pnas.1310880110. ISSN 0027-8424. PMID 23818582. Bibcode: 2013PNAS..11011911I. 
  31. ↑ Carroll, Oliver; Batzer, Evan; Bharath, Siddharth; Borer, Elizabeth T.; Campana, Sofía; Esch, Ellen; Hautier, Yann; Ohlert, Timothy et al. (2021-12-27). Penuelas, Josep. ed. "Nutrient identity modifies the destabilising effects of eutrophication in grasslands" (in en). Ecology Letters 25 (4): 754–765. doi:10.1111/ele.13946. ISSN 1461-023X. PMID 34957674. https://onlinelibrary.wiley.com/doi/10.1111/ele.13946. 
  32. ↑ Conley, Daniel J.; Paerl, Hans W.; Howarth, Robert W.; Boesch, Donald F.; Seitzinger, Sybil P.; Havens, Karl E.; Lancelot, Christiane; Likens, Gene E. (2009-02-20). "Controlling Eutrophication: Nitrogen and Phosphorus" (in en). Science 323 (5917): 1014–1015. doi:10.1126/science.1167755. ISSN 0036-8075. PMID 19229022. https://www.science.org/doi/10.1126/science.1167755. 



Retrieved from "https://handwiki.org/wiki/index.php?title=Earth:Productivity_(ecology)&oldid=3297426"