Current patterns of agricultural expansion and intensification are bringing unprecedented environmental externalities, including impacts on water quality. While water pollution is slowly starting to receive the attention it deserves, the contribution of agriculture to this problem has not yet received sufficient consideration.We need a much better understanding of the causes and effects of agricultural water pollution as well as effective means to prevent and remedy the problem. In the existing literature, information on water pollution from agriculture is highly dispersed. This repost is a comprehensive review and covers different agricultural sectors (including crops, livestock and aquaculture), and examines the drivers of water pollution in these sectors as well as the resulting pressures and changes in water bodies, the associated impacts on human health and the environment, and the responses needed to prevent pollution and mitigate its risks.

Qualitative and quantitative analysis of organochlorine insecticide residues were conducted in water, sediment, aquatic plants and animals from 3 freshwater reservoirs. Ninety water samples, 90 sediment samples, 397 aquatic plants samples and 121 aquatic animals samples were collected during March-April and August-September 1989. There were about 14 kinds of aquatic plants, such as water hyacinth, water lettuce, algae and water lilly etc. Aquatic animals are fish, shrimps and snails, but most of them are fish. They are striped snake-head fish, carp and catfish etc. Total samples of 698 were analyzed by using gas chromatographic techniques at Agricultural Toxic Substances Division. The results indicated that 5 kinds of insecticides were found in most samples. They were lindane, heptachlor, aldrin, dieldrin, DDT and derivatives. Dieldrin was detected at higher concentration and found in all samples. The residue level of dieldrin ranged from 0.01-0.12 ppb in water, 0.005-0.036 ppm in sediment, 0.001-0.138 ppm in aquatic plants and 0.001-0.037 ppm in aquatic animals respectively. The accumulation of dieldrin residue in water and aquatic plant samples from all reservoirs are not different but the level of dieldrin residue in sediment samples from Bueng Boraphed is higher than the other 2 reservoris. However the levels of dieldrin residue in sediment, aquatic plant and aquatic animal samples higher than those in water samples respectively.

Dams provide numerous economic benefits and can mitigate the adverse impacts of water variability and extreme climate events. However, such large-scale water infrastructure has also caused significant social and environmental costs, prompting calls for alternative, nature-based solutions. WLE suggests that collections of built and natural infrastructure, combined with participatory management approaches, can support water and food security, while enhancing livelihoods and environmental outcomes.

Eric Baran, Eric Guerin, Joshua Nasielski, 'Fish, sediment and dams in the Mekong: How hydropower development affects water productivity and food supply', 2016

11 pages, 5 figures, 5 tables, 1 appendix supplementary data https://dx.doi.org/10.1016/j.scitotenv.2016.03.234.-- This work is a contribution to the consolidated research group 2014 SGR 498 of the Generalitat de Catalunya | We analyzed the concentrations of trace metals/metalloids (TMs) in the water, sediment and plankton of two semi-enclosed marine coastal inlets located north of Jurong Island and separated by a causeway (SW Singapore; May 2012-April 2013). The west side of the causeway (west station) has residence times of approximately one year, and the east side of the causeway (east station) has residence times of one month. The concentrations of most of the TMs in water and sediment were higher in the west than in the east station. In the water column, most of the TMs were homogeneously distributed or had higher concentrations at the surface. Preliminary evidence suggests that the TMs are primarily derived from aerosol depositions from oil combustion and industry. Analyses of TMs in seston (>. 0.7 μm; mostly phytoplankton) and zooplankton (>. 100 μm) revealed that the seston from the west station had higher concentrations of most TMs; however, the concentrations of TMs in zooplankton were similar at the two stations. Despite the high levels of TMs in water, sediment and seston, the bioaccumulation detected in zooplankton was moderate, suggesting either the presence of effective detoxification mechanisms or/and the inefficient transfer of TMs from primary producers to higher trophic levels as a result of the complexity of marine planktonic food webs. In summary, the TM concentrations in water and seston are not reliable indicators of the bioaccumulation at higher trophic levels of the food web | This work was funded through grant MadeInPlankton from Singapore National Parks Board - Singapore (NParks) and DHI-NTU Research Centre and Education Hub, Ung EliteForsk grants 10-093759 and 10-094773 from the Danish Ministry for Independent Research to GD, and Projects PROTOS (CTM2009-08783), TOPCOP (CTM2011-23480) and FERMI (CGL2014-59227-R) from the Spanish Ministry of Economy and Competitiveness to AC | Peer Reviewed