The wastewater treatment process is aimed to reduce pollution the appropriate level. An oxidation pond system can treat contaminants in wastewater. Oxidation ponds are use sunlight, bacteria, and algae This study developed an improved mathematical model a graphical user interface (GUI), called oxi-P GUI predict pond. correlation between dissolved oxygen (DO), chemical demand (COD), coliform as ...

Of the non-native fishes introduced to the U.K., the pumpkinseed is one of six species predicted to benefit from the forecasted climate warming conditions. To demonstrate the potential response of adults and their progeny to a water temperature increase, investigations of parental pumpkinseed acclimatization, reproduction and YOY over-wintering were carried out in outdoor experimental ponds und...

1. The shallow ponds of the nature reserve ‘De Maten’ form a metacommunity, in which individual ponds are highly interconnected via a system of overflows and rivulets. This study reports on the relations between cladoceran species richness and (a) connectivity patterns and (b) local environmental variables. 2. No relation was found between local species richness and three connectivity variables...

Using the common carp Cyprinus carpio L. in polyculture ponds to increase both phytoand zooplankton availability has become a popular practice for the cultivation of plankti vorous fish, such as rohu Labeo rohita Hamilton. However, the dynamics of how common carp influences the environment and ecology in polyculture ponds are unclear. In the present study, the effects of various stocking densit...

Gene flow has historically been thought to constrain local adaptation; yet, recent research suggests that populations can diverge despite exchanging genes. Here I use a common garden experiment to assess the combined effects of gene flow and natural selection on morphological variation of 16 wood frog (Rana sylvatica) populations, a species known to experience divergent selection pressures in o...

White-spot syndrome virus (WSSV) is a devastating, infectious virus affecting shrimp. Although sensitive techniques involving PCR have been developed to assist farmers in screening shrimp (brood stock) for WSSV prior to stocking ponds, such practices have not yet been applied in Korea. Despite the rationality of implementing screening, there has been some doubt as to whether the stocking of WSS...

Pond carrying capacity is largely determined by management practices. Earlier work on semiintensive culture of Nile tilapia (Oreochromis niloticus) using manure or inorganic fertilizers indicated that carrying capacity might reach 2,000 to 3,000 kg/ha (Diana et al. 1991a, b; Knud-Hansen et al. 1991). As stocking density is increased in fertilized ponds, carrying capacity remains largely the sam...

The redox transformations of arsenic (As) in lakes are thought to be mainly controlled by algal/microbial processes. We tested if photochemical oxidation could also a significant process northern freshwater systems. exposed filtered natural water samples from four mine-impacted (Northwest Territories, Canada) and three unimpacted ponds (Nunavik, simulated solar radiation, followed As(III) oxida...

background: heavy metals have destructive and irreversible effects on the human, plants and animals. some industries in yazd enter industrial wastewater to municipal wastewater collection system. this can lead to high levels of heavy metals in wastewater and in turn in the wastewater treatment plant effluent.   methods: this study was carried out during four months from december 22, 2009 to may...