The status and protection of the ecological environment in Heihe River water source district

This article discusses the status of the ecological environment in Heihe River water source district, and points out that the decline of the forest coverage, the degradation of the pasture and the shrinking back of the glacier, the increased soil erosion and other phenomena are the main ecological and environmental problems in this area. The main reason is the natural and man-made results. This article proposes the specific measures to protect the ecological environment in Heihe River water source district.

Distribution characteristics and source identification of polychlorinated dibenzo-p-dioxin and dibenzofurans,and dioxin-like polychlorinated biphenyls in the waters from River Kanzaki,running through Osaka urban area,Japan

This is the first to elucidate the distribution and sources of polychlorinated dibenzo-p-dioxins and dibenzofurans （PCDD/PCDFs）,and dioxin-like polychlorinated biphenyls in the waters from Kanzaki River,which is one of the most heavily polluted rivers in Japan.The World Health Organization （WHO）-toxic equivalent quantities （TEQs） in waters from the mainstream exceeded the Japanese environmental standard （1.0 pg-TEQ/L）.The PCDD/PCDFs were dominated by highly chlorinated DFs,which predominantly contributed to the WHO-TEQs,suggesting that the main causes would be the incineration-related wastes.To find the sources,the dioxin congener concentrations in water and sediment samples from its tributary small waterways were determined.Abnormally high WHO-TEQs were detected in a water （50 pg-TEQ/L） and a sediment sample （41,000 ng-TEQ/kg dry weight） near the industrial solid waste incinerators （ISWIs）.The PCDD/PCDF characteristics agreed well with those of the incinerator-related wastes as seen in the mainstream.These facts indicate that the dioxin pollution in the mainstream could be largely related to the industrial wastes from the ISWIs.Here,a TEQ apportionment method was used to understand the contribution of the pyrogenic sources to the WHO-TEQs.The average contribution ratios of the pyrogenic sources to WHO-TEQs were more than 80% for river waters from the mainstream,indicating that the elevated WHO-TEQs in the mainstream had been largely caused by the ISWIs.

Identification of causative compounds and microorganisms for musty odor occurrence in the Huangpu River,China

There are regular problems of musty odor in the Huangpu River,a major source of drinking water for Shanghai,China.In this study,the musty odor and its main causative compounds in the Huangpu River source water were confirmed through a yearly investigation using flavor profile analysis combined with HSPME-GC-MS analysis.The investigation showed that 2-methylisoborneol （2-MIB） with a concentration level between 28.6 and 71.0 ng/L was responsible for the musty odor in summer from July to September.Microscopic observation confirmed with the cloning results showed that Phormidium spp.,which accounted for 80%-95% of the algal cell density,was the microorganisms responsible for the production of 2-MIB and the estimated 2-MIB yield was 0.022 pg/cell.Results from a wide-area sampling campaign in the Huangpu River watershed showed that,other than the large tributaries receiving water from Tai Lake,several small creeks close to the intake may have contributed most of the 2-MIB and the Phormidium spp.to the Huangpu River source water.This study provides methodology for the investigation of odor causing compounds and microorganisms in river-type source water,and the result will be useful for water quality control in both source water and drinking water.

Study on integrated calculation of ecological water demand for basin system

The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecological operation needs to be carried out in order to ensure ecological water use of downstream zone.The key technological support is the estimation and integrated calculation of ecological water demand.The connotation of the integrated calculation on ecological water demand lies on that the ecological water demand of different ecosystems is integrated to meet the requirements of water allocation and operation on watershed scale in terms of hydrological cycle.Considering the practical requirement of ecological operation of reservoir(s),this study proposed an integrated calculation approach of ecological water demand according to the ecological water demand in various ecosystems as well as the hydraulic connection among them;it established an integrated calculation model of regional ecological water demand by means of the distributed hydrological model,and studied the integrated calculation in Yalong River basin which is the source area of the west route of South-North Water Transfer Project as an example.The results indicated that the integrated calculation model more effectively combined the ecological water demand and hydraulic connection of ecosystems in time and space,compared with the lumped water balance analysis,since the former conquered the defect of insufficient ecological water source and supplement on multiple spatial and temporal scales,and met the demand of ecological operation of reservoir(s).