John,WH; Anderson,BS; Philips,BM; Tjeerdema,RS; Puckett, HM; Vlaming, V (1999): Pattern of aquatic of aquatic toxicity in an agriculturally dominated coastal wetershed in California. Agriculture, Ecosystems and Environmental, 75:75-91.

This study was designed to investigate the occurrence, severity, sources and causes of aquatic toxicity in a coastal river and estuary subject to non-point source pollutant inputs from adjacent agricultural and urban areas. The Pajaro River estuarine system on the central coast of California. USA, receives subsurface tile drain runoff from irrigated cropland and seasonal surface runoff from agricultural, urban, industrial, and residential areas. Seven sites in the estuary upstream river tributary sloughs, and agricultural drainage ditches were selected to identify tributaries that might contribute toxic runoff to the estuary. These sites were each sampled 18 times over an 18-month period, and water samples were tested for toxicity to the mysid Neomysis mercedis a resident crustacean. Results indicated toxicity in 78% of agricultural ditch samples, 25% of tributary sloughs samples, and 11% of river and estuary samples. Temporal patterns in the occurrence of toxicity indicated that agricultural ditches and Upper River were more important than the freshwater sloughs as sources of toxic runoff to the estuary. Chemical analyses were conducted on samples collected at each site on two occasions. Organophosphate pesticides were detected in samples collected when the river flow rate was low, and persistent hydrophobic organochlorine pesticides were detected after high surface runoff. Three pesticides (toxaphene, DDT, and diazinon) were found at concentrations higher than published toxicity thresholds for resident aquatic species. Toxicity in the estuary was significantly correlated with increased river flow. Chemical causes of toxicity were investigated in two preliminary and four full Phase I Toxicity Identification Evaluations (TIEs ) on six separate samples from the agricultural drainage ditches receiving tile drain discharges. The TIE results indicated that multiple compounds were responsible for toxicity in all samples evaluated, and that non-polar and perhaps polar organic compounds were present in toxic concentrations.

Khandkar,UR; Gangwar,MS; Srivastava,PC (1999): Effect of fly ash on some properties of an acid soil, elemental composition and yield of crops. Pollution Research, 18(1): 101-107.

The effect of soil application of a ‘thermal power station fly ash (2 to 20 per cent of soil weight) was investigated on properties of an acid soil, elemental composition and yields of rice, soybean and blackgram crops. The application of fly ash altered the soil texture and increased water-holding capacity. pH and electrical conductivity and extractable amount of P, Ca, Mg, S, Fe, Mn, Zn, Cu, B and Al but decreased soil particle density and available soil N. Soil application of fly ash increased the concentration of all the nutrients, Na and Al in seed and straw of all the three crops except N in all the cases and P and K in rice. The application of fly ash increased the seed and straw yield of all the three crops with no adverse effect on yields even at 20 per cent level. Fly ash can be used to correct S and B deficiency in acid soils.

Lawrence,BC; Mikucki, JA; Mallin,MA (1999): Nitrogen and phosphorus imports to the Cape Fear and Neuse river basins to support intensive livestock production. Environmental Sciences & Technology, 33(3): 410-415.

Feeds imported to support rapidly expanding intensive livestock operations (ILOs) in North Carolina represent significant quantities and proportions of "new" nutrients in local watersheds. The Cape Fear and Neuse River basins include large fractions of total state inventories of hogs, turkeys, chickens, and cattle. Production of hogs, turkeys, and broiler chickens increased substantially in North Carolina during 1985-1995. Due to growth in the demand for feed and declines in feed crop production in North Carolina, ILOs must import large fractions of feed grains and soybeans they require from out of state. The corresponding quantities of new nitrogen and phosphorus, including inorganic phosphorus used as a diet supplement, imported in animal feeds are more than an order of, magnitude greater than current annual loads of these nutrients in each river. The eutrophication threat to these river basins and other areas with expanding animal populations from the potential large nutrient loading, especially phosphorus, associated with ILOs is substantial.

Lee,HD; Memebr,PE (1999): Institutional and technical barriers to risk-based water resources management: A case study. Journal of Planning Management, 125(4): 186-193.

Implementing risk-based Great Lakes water level management and forecasting, as recommended by the International Joint Commission, would allow managers and other interests affected by fluctuating water levels to consider the wide range of potential future lake levels, incorporate some of the uncertainty inherent in forecasts, and allow explicit consideration of risk. Decision making that requires knowledge of future lake levels would potentially improve, resulting in economic and environmental benefits. Significant institutional and technical barriers preventing implementation exist, among them the lack of International Joint Commission authority to mandate other agencies to implement its recommendations, and the lack of objective evidence that risk-based water level management is an improvement over current procedures. Strategies for overcoming these and other barriers are suggested. The barriers and strategies specific to this case study are generalized so that other water resource managers may consider them when applying risk-based management to their systems.

Malathi,T; Princy Merlin,J; Rajendran,A; Jeyakar Chellaraj,DA; Subramanian,NS (1999): A study on the applicability of a new water quality index- HWQI. Indian Journal of Environmental Protection, 19(1): 43-47.

Pollution load of fresh water bodies has been assessed by scholars using many independent parameters according to their Perspectives. In this work, an attempt had been made to formulate a new water quality index called Heber water quality index 1 in accordance with our climatic condition, industrialization, population pressure, etc. The National Sanitation Foundation ( NSF ) of USA has formulated a water quality Index (WQI ) based on ‘the analysis of nine parameters, namely temperature (DT ), turbidity, total solids, DO, BOD, pH, nitrates, phosphate’’-’ phosphorous and fecal coliform. It is found to be suitable for testing the water quality. In temperate regions, like USA. Hence HWQII table was prepared using the data collected from scholars. In this area by replacing the parameters, namely DT and phosphate phosphorous in NSF - WQI table by 2 other important parameters - fluoride and chromium. Water samples were collected from 5 different rivers around Trichy district and the water quality parameters suggested by NSF - WQI and HWQI, were analysed to express the quality and quantity of pollution comparatively for each sample.