There is no common understanding of the minimum per capita fresh water requirement for human health and economic and social development. Existing estimates vary between 20 and 4,654 l/c/d, however, these estimates are methodologically problematic as they consider only human consumptive and hygiene needs, or they consider economic needs but not the effects of trade. Reconsidering the components ...

Due to industrialization and environmental effects the drinking water quality has been greatly affected in Pakistan. A number of industries are draining their waste containing heavy metals without any treatment in effluents. As a result of this practice almost all of the fresh water resources are getting contaminated, although the deep aquifer in most of the countries is still safe from contami...

Proliferative gill disease (PGD) in channel catfish Ictalurus punctatus is caused by the myxozoan parasite Henneguya ictaluri. There is no effective treatment for PGD, and mortalities can exceed 50% in severe outbreaks. One approach to controlling losses would be to utilize a less susceptible ictalurid species in pond culture; alternatively, one could identify the traits that convey resistance ...

Ž . Ž . Ž . Ž . Feed intake FI , feed efficiency FE , protein efficiency ratio PER and weight gain WG of Ž . juvenile channel catfish initially weighing 15.0"0.23 g 10–12 cm initial total length were Ž evaluated under three regimes of time-varying water temperature mean daily water temperature . Ž for Stoneville, MS, USA; mean q3; and, mean y38C and three of dissolved oxygen DO; 100, . 70 and 3...

A large commercial catfish enterprise encompassing over 500 food fish ponds from five farms covering multiple counties in the Mississippi Delta was included in this analysis of columnaris risk factors. A gram-negative bacterium, Flavobacterium columnare, is the cause of columnaris disease and is considered the second-most prevalent bacterial disease in farm-raised catfish. The objective of this...

Methylmercury [MeHg(I) in the aerobic surface water of lakes is thought to be rapidly degraded, but contrary to expectations, we show that MeHg(I) concentrations often increase during sunlight hours or remain relatively constant. We hypothesized that there were water column processes that generated MeHg(I) and that these processes were linked to dissolved organic matter (DOM) and solar radiatio...

Worldwide, an estimated 2 billion people live primarily on a meat-based diet, while an estimated 4 billion live primarily on a plant-based diet. The US food production system uses about 50% of the total US land area, 80% of the fresh water, and 17% of the fossil energy used in the country. The heavy dependence on fossil energy suggests that the US food system, whether meat-based or plant-based,...

Pelagic bacterial production is often positively correlated, or coupled, with primary production through utilization of autotrophically produced dissolved organic carbon. Recent studies indicate that inorganic N or P can directly limit both bacterial and phytoplanktonic growth. Our mesocosm experiments, with whole communities from mesotrophic Calder Lake, test whether this apparent bacterial-al...

Climate change and forest disturbances are threatening the ability of forested mountain watersheds to provide the clean, reliable, and abundant fresh water necessary to support aquatic ecosystems and a growing human population. Here, we used 76 years of water yield, climate, and field plot vegetation measurements in six unmanaged, reference watersheds in the southern Appalachian Mountains of No...

There is the need to re-configure current urban water systems to achieve the objective of sustainable water sensitive cities. Stormwater represents a valuable alternative urban water source to reduce pressure on fresh water resources, and to mitigate the environmental impact of urban stormwater runoff. The selection of suitable urban stormwater harvesting sites is generally based on the judgeme...