tailieunhanh - Excess Nitrogen in the U.S. Environment: Trends, Risks, and Solutions

The Mangalore coast which is situated at the western part of the Indian peninsula stretching to about 22 Kms of Coastal district of Dakshina Kannada, Karnataka. The healthy condition of the aquatic system depends upon its physical, chemical and biological characteristics which actually fluctuate with season and degree of pollution. Marine ecosystem is one of the richest ecosystems (Cairns & Dickson, 1971). Industrialisation, development activities in coastal zones have placed enormous stress on habitats. For the better management of natural marine system, observational and experimental studies, monitoring the diversity of various life forms and ecosystem functioning are inevitable | ISSUES in EcGLGGy Published by the Ecological Society of America Excess Nitrogen in the . Environment Trends Risks and Solutions Eric A. Davidson Mark B. David James N. Galloway Christine L. Goodale Richard Haeuber John A. Harrison Robert W. Howarth Dan B. Jaynes R. Richard Lowrance B. Thomas Nolan Jennifer L. Peel Robert W. Pinder Ellen Porter Clifford S. Snyder Alan R. Townsend and Mary H. Ward Winter 2012 esa Report Number 15 Issues in Ecology Number Fifteen Winter 2012 Excess Nitrogen in the . Environment Trends Risks and Solutions Summary It is not surprising that humans have profoundly altered the global nitrogen N cycle in an effort to feed 7 billion people because nitrogen is an essential plant and animal nutrient. Food and energy production from agriculture combined with industrial and energy sources have more than doubled the amount of reactive nitrogen circulating annually on land. Humanity has disrupted the nitrogen cycle even more than the carbon C cycle. We present new research results showing widespread effects on ecosystems biodiversity human health and climate suggesting that in spite of decades of research quantifying the negative consequences of too much available nitrogen in the biosphere solutions remain elusive. There have been important successes in reducing nitrogen emissions to the atmosphere and this has improved air quality. Effective solutions for reducing nitrogen losses from agriculture have also been identified although political and economic impediments to their adoption remain. Here we focus on the major sources of reactive nitrogen for the United States . their impacts and potential mitigation options Sources Intensive development of agriculture industry and transportation has profoundly altered the . nitrogen cycle. Nitrogen emissions from the energy and transportation sectors are declining but agricultural emissions are increasing. Approximately half of all nitrogen applied to boost agricultural production escapes its