Agricultural input is the main cause for pollution of water bodies. Pesticides and other agro chemical products accumulate in water and affect inland fishing.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/water-bodies-pollution-agricultural-input-main-cause
[2] http://admin.indiaenvironmentportal.org.in/category/author/ishara-mudugamuwa
[3] http://admin.indiaenvironmentportal.org.in/category/newspaper/daily-news-sri-lanka
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/sri-lanka
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pollution
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/agriculture
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/pesticides
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/drinking-water
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/sewage