Assessment of nitrogen flows into the Cuban landscape
The alteration of the nitrogen (N) cycle by human activities is widespread and has often resulted in increased flows of nitrogen to the marine environment. In this paper we have attempted to know the changes of N fluxes in Cuba by quantifying the N inputs to the landscape from (1) fertilizer applica...
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2006
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ftoceandocs:oai:aquadocs.org:1834/5111 |
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openpolar |
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Open Polar |
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IODE-UNESCO: OceanDocs - E-Repository of Ocean Publications |
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ftoceandocs |
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English |
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Atmospheric deposition Fertilizers Nitrogen Nitrogen cycle |
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Atmospheric deposition Fertilizers Nitrogen Nitrogen cycle Baisre, J. A. Assessment of nitrogen flows into the Cuban landscape |
| topic_facet |
Atmospheric deposition Fertilizers Nitrogen Nitrogen cycle |
| description |
The alteration of the nitrogen (N) cycle by human activities is widespread and has often resulted in increased flows of nitrogen to the marine environment. In this paper we have attempted to know the changes of N fluxes in Cuba by quantifying the N inputs to the landscape from (1) fertilizer applications, (2) atmospheric deposition, (3) biological nitrogen fixation and (4) net import of food and feeds. N-inputs to the country progressively increased until the end of the 20th century, reaching a peak during the 80s when low cost fertilizer imported from the former Soviet Union led to heavy rates of application. This rapid growth represented more than a 5-fold increase with respect to pristine values; higher than the two-fold global increase of anthropogenic N reported by Vitousek et al. (1997 Human alteration of the global nitrogen cycle: sources and consequences. Ecol. Appl. 7:737-750). Inorganic fertilizer was the largest single source of reactive N, followed by atmospheric deposition, biological fixation, and net imports of foods and feedstocks. Nitrogen inputs peaked in 1987 and data expressed on an area basis show that N flux to the Cuban landscape, in the 80s, was one of the highest reported in the literature. During the 90s, there was a dramatic drop in nitrogen inputs mainly associated to a decrease in the use of inorganic fertilizer. Other factors reducing nutrient inflows to Cuba, during the same period, were imports of foodstuff and livestock feeds, a decrease of nitrogen oxide emissions, and a decrease in the sugar cane crop area. Using an empirical relationship (Howarth et al. 1996 Regional nitrogen budgets and riverine N & O fluxes for the drainages to the North Atlantic Ocean: Natural and human influences. Biogeochemistry 35:75-139) we present a very preliminary estimate of N-inputs to coastal waters and discuss the consequences of these changes on the coastal zone. La alteración del ciclo del nitrógeno (N) por la actividad humana está muy extendida y con frecuencia se ha traducido en un ... |
| format |
Book |
| author |
Baisre, J. A. |
| author_facet |
Baisre, J. A. |
| author_sort |
Baisre, J. A. |
| title |
Assessment of nitrogen flows into the Cuban landscape |
| title_short |
Assessment of nitrogen flows into the Cuban landscape |
| title_full |
Assessment of nitrogen flows into the Cuban landscape |
| title_fullStr |
Assessment of nitrogen flows into the Cuban landscape |
| title_full_unstemmed |
Assessment of nitrogen flows into the Cuban landscape |
| title_sort |
assessment of nitrogen flows into the cuban landscape |
| publishDate |
2006 |
| url |
http://hdl.handle.net/1834/5111 |
| op_coverage |
Cuba |
| genre |
North Atlantic |
| genre_facet |
North Atlantic |
| op_relation |
10.1007/s10533-006-9004-z Aleem A.A. 1972. Effect of river outflow management on marine life. Mar. Biol. 15: 200–208. Alexander R.A., Johnes P.J., Boyer E.W. and Smith R.A. 2002. A comparison of methods for estimating the riverine export of nitrogen from large watersheds. Biogeochemistry 57/58: 295–339. Baisre J.A. 1985. Los Complejos Ecolo´ gicos de Pesca: Su importancia en la administracio´ n de las pesquerı´ as cubanas. FAO Fish Rep. 278(Suppl.): 251–272. Baisre J.A. 2000. Chronicle of Cuban Marine Fisheries 1935–1995: Trend analysis and fisheries potential. FAO Fish. Tech. Pap. 394, 26 pp. Boesch D.F. 2001. Causes and consequences of nutrient overenrichment of coastal waters. In: Ragaini R. (ed.), International Seminar on Nuclear War and Planetary Emergencies. 25th Session, World Scientific publishing, Singapore, pp. 165–180. Boyer E.W., Goodale C.L., Jaworski N.A. and Howarth R.W. 2002. Anthropogenic nitrogen sources and relationships to riverine nitrogen export in the northeastern U.S.A. Biogeochemistry 57/58: 137–169. Caddy J.F. 1993. Towards a comparative evaluation of human impacts on fishery ecosystems of enclosed and semi-enclosed seas. Rev. Fish. Sci. 1(1): 57–95. Caddy J.F. and Bakun A. 1994. A tentative classification of coastal marine ecosystems based on dominant processes of nutrient supply. Ocean Coastal Manag. 23: 201–211. Caddy J.F. and Bakun A. 1995. Marine Catchment Basins and anthropogenic effects on coastal fishery ecosystems. FAO Fish. Rep. 349: 119–133. Caddy J.F. 2000. Marine catchment basin effects versus impact of fisheries on semienclosed seas. ICES J. Mar. Sci. 57: 628–640. Caraco N.F. and Cole J.J. 1999. Human impact of nitrate export: an analysis using major world rivers. Ambio 28(2): 167–170. Centella A., Llanes J., Lo´ pez C. and Limia M. 2000. First National Report to the United Nation Convention on Climate Change (Spanish). Instituto de Meteorologı´ a, La Habana, Cuba.Cleveland C.C., Townsend A.R., Schimel D.S., Fisher H., Howarth R.W., Hedin L.O., Perakis S.S., Latty E-.F-., Von Fischer J.C., Elseroad A. and Mason M.F. 1999. Global patterns of terrestrial biological nitrogen (N2) fixation in natural ecosystems. Global Biochem. Cycles 13: 623–645. Cloern J.E. 2001. Our evolving conceptual model of the coastal eutrophication problem. Mar. Ecol. Prog. Ser. 210: 223–253. Cubagua 2004. Cuban data base on water resources. (http://www.hidro.cu). Cuesta Santos O., Ortiz Bulto P.L. and Gonza´ lez M.L. 1998. Deposition and atmospheric nitrogen concentrations trends in Cuba. Water, Air, Soil Pollution 106: 163–169. Dacal Moure R. and Rivero de la Calle M. 1986. Arqueologı´ a aborigen de Cuba. Editorial Gente Nueva, La Habana, 174 pp. Deegan L.A., Day J.W. Jr., Yan˜ ez-Arencibia A., Gosselink J.G., Sobero´ n-Cha´ vez G. and Sa´ nchez- Gil P. 1986. Relationships among physical characteristics, vegetation, distributions, and fisheries yield in Gulf of Mexico estuaries. In: Wolfe D.A. (ed.), Estuarine Variability, Academic Press, NewYork, pp. 83–100. Dennis R. 1997. Using the Regional Acid Deposition Model to determine the nitrogen deposition airshed of the Chesapeake Bay watershed. In: Baker J.E. (ed.), Atmospheric Deposition of Contaminants to the Great Lakes and Coastal Waters, SETAC Press, Pensacola, Florida, pp. 393–413. Downing J.A., Mcclain M., Twilley R., Melack J.M., Elser J., Rabalais N.N., Lewis W.M. Jr., Turner R.E., Corredor J., Soto D., Yan˜ es-Arencibia A., Kopaska J.A. and Howarth R.W. 1999. The impact of accelerating land-use change on the N-Cycle of tropical aquatic ecosystems: current conditions and projected changes. Biogeochemistry 46: 109–148. FAO 2003. Fertilizer Used by Crop in Cuba. Food and Agriculture Organization of the United Nations, Rome, 28 pp. FAOSTAT 2004. Food and Agriculture Organization of the United Nations FAOSTAT Agriculture Data. (http://www.apps.fao.org/). Galloway J.N. and Cowling E.B. 2002. Reactive nitrogen and the world: 200 Years of change. Ambio 31(2): 64–71. Galloway J.N., Dentener F.J., Capone D.G., Boyer E.W., Howarth R.W., Seitzinger S.P., Asner G.P., Cleveland C., Green P., Holland E., Karl D.M., Michaels A.F., Porter J.H., Townsed A. and Voro¨ smarty C. 2004. Nitrogen cycles: past, present and future. Biogeochemistry 70: 153–226. Galloway J.N., Schlesinger W., Levy H. II, Michaels A. and Schnoor J.L. 1995. Nitrogen fixation: Atmosopheric enhancement-environmental response. Global Biochem. cycles 9: 235–252. Grimes C.B. 2001. Fishery production and the Mississippi river discharge. Fisheries, 26(8): 17–26. Howarth R.W., Billen G., Swaney D., Townsend A., Jaworski N., Lajtha K., Downing J.A., Elmgen R., Caraco N., Jordan T., Berendse F., Freney J., Kudeyarov V., Murdoch P. and Zhu Zhao-Liang 1996. Regional nitrogen budgets and riverine N & O fluxes for the drainages to the North Atlantic Ocean: Natural and human influences. Biogeochemistry 35: 75–139. Howarth R.W., Anderson D., Cloern J., Elfring C., Hopkinson C., Lapointe B., Malone T., Marcus N., McGlathery K., Sharpley A. and Walker D. 2000. Nutrient Pollution of coastal rivers, bays and seas. Issues Ecol. 7, 15 pp. Howarth R.H., Boyer E., Pabich W. and Galloway J.N. 2002. Nitrogen use in the United States from 1961–2000, and estimates of potential future trends. Ambio 31: 88–96. IIIA (1985). Tabla de Composicio´ n de Alimentos. Instituto de Investigaciones de la Industria Alimenticia e Instituto Nacional de Higiene de los Alimentos, 6 pp. IFA (International Fertilizer Industry Association) 2004. Nitrogen, phosphate and potash statistics (http://www.fertilizer.org/ifa/statistics/IFADATA/dataline.asp). Jordan T.E. and Weller D.E. 1996. Human contributions to terrestrial nitrogen flux. Bioscience 46: 655–664. Kideys A.E. 2002. Fall and rise of the black sea ecosystem. Science 297: 1482–1484. Marrero L. 1950. Geografı´a de Cuba. Talleres Tipogra´ ficos Alfa, La Habana, 736 pp. Nixon S.W. 1995. Coastal marine eutrophication: a definition, social causes, and future concerns. Ophelia 41: 199–219.Matson P.A., Mc Dowell W.H., Townsend A.R. and Vitousek P.M. 1999. The globalization of N deposition: ecosystem consequences in tropical environments. Biogeochemistry 46: 67–83. ONE 2002. Oficina Nacional de Estadı´ sticas. Anuario Estadı´ stico de Cuba 2001, (Yearbook of Statistics 2001) (Spanish), 335 pp. Pearl H. 1985. Enhancement of marine primary production by nitrogen-enriched acid rain. Nature 315: 747–749. Peoples M.B., Herridgeand D.F. and Ladha J.K. 1995. Biological nitrogen fixation: an efficient source of nitrogen for sustainable agricultural production?. Plant and soil 174: 3–28. Rabalais N.N. 2002. Nitrogen in aquatic ecosystems. Ambio 31: 102–112. Ryther J. and Dunstan W. 1971. Nitrogen, phosphorus, and eutrophication in the coastal marine environment. Science 171: 1008–1012. Schimel D.S., Braswell B.H., McKeown R., Ojima D.S., Parton W.J. and Pulliam W. 1996. Climate and nitrogen controls on the geography and timescales of terrestrial biochemical cycling. Global Biogeochem. Cycles 10: 677–692. Smil V. 1997. Global population and the nitrogen cycle. Scientific American July: 76–81. Smil V. 1999. Nitrogen in crop production: an account of global flows. Global Biochem. Cycles 13: 647–662. Smith E.E. 1954. The Forest of Cuba. Maria Moors Cabot Foundation Publ. 2, 98 pp. Stockner J.G., Rydin E. and Hyenstrand P. 2000. Cultural oligotrophication: causes and consequences for fisheries resources. Fisheries 25(5): 7–14. Tabı´o E.E. and Rey E. 1985. Prehistoria de Cuba. Editorial de Ciencias Sociales, La Habana, 234 pp. Vitousek P.M., Aber J.D., Howarth R.W., Likens G.E., Matson P.A., Schindler D.W., Schlesinger W.H. and Tilman D.G. 1997. Human alteration of the global nitrogen cycle: sources and consequences. Ecol. Appl. 7: 737–750. Watanabe I. 1986. Nitrogen fixation by non-legumes in tropical agriculture with special reference to wetland rice. Plant Soil 90: 343–357. Yan W., Zhang S., Sun P. and Seitzinger S.P. 2003. How do nitrogen inputs to the Changjiang basin impact the Changjiang river nitrate: A temporal analysis for 1968–1997. Global Biochem. Cycles 17(4): 1091–1100. WRI 2001. Nutrient Overload Unbalancing the Global Nitrogen Cycle. Earth Trends 2001. World Research Institute, pp.1–3. Biochemistry, 79, p. 91-108 0006-2960 http://hdl.handle.net/1834/5111 |
| op_rights |
http://creativecommons.org/licenses/by-nc/3.0/ |
| _version_ |
1766136641363116032 |
| spelling |
ftoceandocs:oai:aquadocs.org:1834/5111 2023-05-15T17:36:58+02:00 Assessment of nitrogen flows into the Cuban landscape Baisre, J. A. Cuba 2006 http://hdl.handle.net/1834/5111 en eng 10.1007/s10533-006-9004-z Aleem A.A. 1972. Effect of river outflow management on marine life. Mar. Biol. 15: 200–208. Alexander R.A., Johnes P.J., Boyer E.W. and Smith R.A. 2002. A comparison of methods for estimating the riverine export of nitrogen from large watersheds. Biogeochemistry 57/58: 295–339. Baisre J.A. 1985. Los Complejos Ecolo´ gicos de Pesca: Su importancia en la administracio´ n de las pesquerı´ as cubanas. FAO Fish Rep. 278(Suppl.): 251–272. Baisre J.A. 2000. Chronicle of Cuban Marine Fisheries 1935–1995: Trend analysis and fisheries potential. FAO Fish. Tech. Pap. 394, 26 pp. Boesch D.F. 2001. Causes and consequences of nutrient overenrichment of coastal waters. In: Ragaini R. (ed.), International Seminar on Nuclear War and Planetary Emergencies. 25th Session, World Scientific publishing, Singapore, pp. 165–180. Boyer E.W., Goodale C.L., Jaworski N.A. and Howarth R.W. 2002. Anthropogenic nitrogen sources and relationships to riverine nitrogen export in the northeastern U.S.A. Biogeochemistry 57/58: 137–169. Caddy J.F. 1993. Towards a comparative evaluation of human impacts on fishery ecosystems of enclosed and semi-enclosed seas. Rev. Fish. Sci. 1(1): 57–95. Caddy J.F. and Bakun A. 1994. A tentative classification of coastal marine ecosystems based on dominant processes of nutrient supply. Ocean Coastal Manag. 23: 201–211. Caddy J.F. and Bakun A. 1995. Marine Catchment Basins and anthropogenic effects on coastal fishery ecosystems. FAO Fish. Rep. 349: 119–133. Caddy J.F. 2000. Marine catchment basin effects versus impact of fisheries on semienclosed seas. ICES J. Mar. Sci. 57: 628–640. Caraco N.F. and Cole J.J. 1999. Human impact of nitrate export: an analysis using major world rivers. Ambio 28(2): 167–170. Centella A., Llanes J., Lo´ pez C. and Limia M. 2000. First National Report to the United Nation Convention on Climate Change (Spanish). Instituto de Meteorologı´ a, La Habana, Cuba.Cleveland C.C., Townsend A.R., Schimel D.S., Fisher H., Howarth R.W., Hedin L.O., Perakis S.S., Latty E-.F-., Von Fischer J.C., Elseroad A. and Mason M.F. 1999. Global patterns of terrestrial biological nitrogen (N2) fixation in natural ecosystems. Global Biochem. Cycles 13: 623–645. Cloern J.E. 2001. Our evolving conceptual model of the coastal eutrophication problem. Mar. Ecol. Prog. Ser. 210: 223–253. Cubagua 2004. Cuban data base on water resources. (http://www.hidro.cu). Cuesta Santos O., Ortiz Bulto P.L. and Gonza´ lez M.L. 1998. Deposition and atmospheric nitrogen concentrations trends in Cuba. Water, Air, Soil Pollution 106: 163–169. Dacal Moure R. and Rivero de la Calle M. 1986. Arqueologı´ a aborigen de Cuba. Editorial Gente Nueva, La Habana, 174 pp. Deegan L.A., Day J.W. Jr., Yan˜ ez-Arencibia A., Gosselink J.G., Sobero´ n-Cha´ vez G. and Sa´ nchez- Gil P. 1986. Relationships among physical characteristics, vegetation, distributions, and fisheries yield in Gulf of Mexico estuaries. In: Wolfe D.A. (ed.), Estuarine Variability, Academic Press, NewYork, pp. 83–100. Dennis R. 1997. Using the Regional Acid Deposition Model to determine the nitrogen deposition airshed of the Chesapeake Bay watershed. In: Baker J.E. (ed.), Atmospheric Deposition of Contaminants to the Great Lakes and Coastal Waters, SETAC Press, Pensacola, Florida, pp. 393–413. Downing J.A., Mcclain M., Twilley R., Melack J.M., Elser J., Rabalais N.N., Lewis W.M. Jr., Turner R.E., Corredor J., Soto D., Yan˜ es-Arencibia A., Kopaska J.A. and Howarth R.W. 1999. The impact of accelerating land-use change on the N-Cycle of tropical aquatic ecosystems: current conditions and projected changes. Biogeochemistry 46: 109–148. FAO 2003. Fertilizer Used by Crop in Cuba. Food and Agriculture Organization of the United Nations, Rome, 28 pp. FAOSTAT 2004. Food and Agriculture Organization of the United Nations FAOSTAT Agriculture Data. (http://www.apps.fao.org/). Galloway J.N. and Cowling E.B. 2002. Reactive nitrogen and the world: 200 Years of change. Ambio 31(2): 64–71. Galloway J.N., Dentener F.J., Capone D.G., Boyer E.W., Howarth R.W., Seitzinger S.P., Asner G.P., Cleveland C., Green P., Holland E., Karl D.M., Michaels A.F., Porter J.H., Townsed A. and Voro¨ smarty C. 2004. Nitrogen cycles: past, present and future. Biogeochemistry 70: 153–226. Galloway J.N., Schlesinger W., Levy H. II, Michaels A. and Schnoor J.L. 1995. Nitrogen fixation: Atmosopheric enhancement-environmental response. Global Biochem. cycles 9: 235–252. Grimes C.B. 2001. Fishery production and the Mississippi river discharge. Fisheries, 26(8): 17–26. Howarth R.W., Billen G., Swaney D., Townsend A., Jaworski N., Lajtha K., Downing J.A., Elmgen R., Caraco N., Jordan T., Berendse F., Freney J., Kudeyarov V., Murdoch P. and Zhu Zhao-Liang 1996. Regional nitrogen budgets and riverine N & O fluxes for the drainages to the North Atlantic Ocean: Natural and human influences. Biogeochemistry 35: 75–139. Howarth R.W., Anderson D., Cloern J., Elfring C., Hopkinson C., Lapointe B., Malone T., Marcus N., McGlathery K., Sharpley A. and Walker D. 2000. Nutrient Pollution of coastal rivers, bays and seas. Issues Ecol. 7, 15 pp. Howarth R.H., Boyer E., Pabich W. and Galloway J.N. 2002. Nitrogen use in the United States from 1961–2000, and estimates of potential future trends. Ambio 31: 88–96. IIIA (1985). Tabla de Composicio´ n de Alimentos. Instituto de Investigaciones de la Industria Alimenticia e Instituto Nacional de Higiene de los Alimentos, 6 pp. IFA (International Fertilizer Industry Association) 2004. Nitrogen, phosphate and potash statistics (http://www.fertilizer.org/ifa/statistics/IFADATA/dataline.asp). Jordan T.E. and Weller D.E. 1996. Human contributions to terrestrial nitrogen flux. Bioscience 46: 655–664. Kideys A.E. 2002. Fall and rise of the black sea ecosystem. Science 297: 1482–1484. Marrero L. 1950. Geografı´a de Cuba. Talleres Tipogra´ ficos Alfa, La Habana, 736 pp. Nixon S.W. 1995. Coastal marine eutrophication: a definition, social causes, and future concerns. Ophelia 41: 199–219.Matson P.A., Mc Dowell W.H., Townsend A.R. and Vitousek P.M. 1999. The globalization of N deposition: ecosystem consequences in tropical environments. Biogeochemistry 46: 67–83. ONE 2002. Oficina Nacional de Estadı´ sticas. Anuario Estadı´ stico de Cuba 2001, (Yearbook of Statistics 2001) (Spanish), 335 pp. Pearl H. 1985. Enhancement of marine primary production by nitrogen-enriched acid rain. Nature 315: 747–749. Peoples M.B., Herridgeand D.F. and Ladha J.K. 1995. Biological nitrogen fixation: an efficient source of nitrogen for sustainable agricultural production?. Plant and soil 174: 3–28. Rabalais N.N. 2002. Nitrogen in aquatic ecosystems. Ambio 31: 102–112. Ryther J. and Dunstan W. 1971. Nitrogen, phosphorus, and eutrophication in the coastal marine environment. Science 171: 1008–1012. Schimel D.S., Braswell B.H., McKeown R., Ojima D.S., Parton W.J. and Pulliam W. 1996. Climate and nitrogen controls on the geography and timescales of terrestrial biochemical cycling. Global Biogeochem. Cycles 10: 677–692. Smil V. 1997. Global population and the nitrogen cycle. Scientific American July: 76–81. Smil V. 1999. Nitrogen in crop production: an account of global flows. Global Biochem. Cycles 13: 647–662. Smith E.E. 1954. The Forest of Cuba. Maria Moors Cabot Foundation Publ. 2, 98 pp. Stockner J.G., Rydin E. and Hyenstrand P. 2000. Cultural oligotrophication: causes and consequences for fisheries resources. Fisheries 25(5): 7–14. Tabı´o E.E. and Rey E. 1985. Prehistoria de Cuba. Editorial de Ciencias Sociales, La Habana, 234 pp. Vitousek P.M., Aber J.D., Howarth R.W., Likens G.E., Matson P.A., Schindler D.W., Schlesinger W.H. and Tilman D.G. 1997. Human alteration of the global nitrogen cycle: sources and consequences. Ecol. Appl. 7: 737–750. Watanabe I. 1986. Nitrogen fixation by non-legumes in tropical agriculture with special reference to wetland rice. Plant Soil 90: 343–357. Yan W., Zhang S., Sun P. and Seitzinger S.P. 2003. How do nitrogen inputs to the Changjiang basin impact the Changjiang river nitrate: A temporal analysis for 1968–1997. Global Biochem. Cycles 17(4): 1091–1100. WRI 2001. Nutrient Overload Unbalancing the Global Nitrogen Cycle. Earth Trends 2001. World Research Institute, pp.1–3. Biochemistry, 79, p. 91-108 0006-2960 http://hdl.handle.net/1834/5111 http://creativecommons.org/licenses/by-nc/3.0/ Atmospheric deposition Fertilizers Nitrogen Nitrogen cycle Journal Contribution Refereed Article 2006 ftoceandocs 2023-04-06T16:58:36Z The alteration of the nitrogen (N) cycle by human activities is widespread and has often resulted in increased flows of nitrogen to the marine environment. In this paper we have attempted to know the changes of N fluxes in Cuba by quantifying the N inputs to the landscape from (1) fertilizer applications, (2) atmospheric deposition, (3) biological nitrogen fixation and (4) net import of food and feeds. N-inputs to the country progressively increased until the end of the 20th century, reaching a peak during the 80s when low cost fertilizer imported from the former Soviet Union led to heavy rates of application. This rapid growth represented more than a 5-fold increase with respect to pristine values; higher than the two-fold global increase of anthropogenic N reported by Vitousek et al. (1997 Human alteration of the global nitrogen cycle: sources and consequences. Ecol. Appl. 7:737-750). Inorganic fertilizer was the largest single source of reactive N, followed by atmospheric deposition, biological fixation, and net imports of foods and feedstocks. Nitrogen inputs peaked in 1987 and data expressed on an area basis show that N flux to the Cuban landscape, in the 80s, was one of the highest reported in the literature. During the 90s, there was a dramatic drop in nitrogen inputs mainly associated to a decrease in the use of inorganic fertilizer. Other factors reducing nutrient inflows to Cuba, during the same period, were imports of foodstuff and livestock feeds, a decrease of nitrogen oxide emissions, and a decrease in the sugar cane crop area. Using an empirical relationship (Howarth et al. 1996 Regional nitrogen budgets and riverine N & O fluxes for the drainages to the North Atlantic Ocean: Natural and human influences. Biogeochemistry 35:75-139) we present a very preliminary estimate of N-inputs to coastal waters and discuss the consequences of these changes on the coastal zone. La alteración del ciclo del nitrógeno (N) por la actividad humana está muy extendida y con frecuencia se ha traducido en un ... Book North Atlantic IODE-UNESCO: OceanDocs - E-Repository of Ocean Publications |