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Investigating Temporal Variation of Water Quality and Benthic Macroinvertebrates in Taudaha Lake, Kathmandu, Nepal

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Journal of Water Resource and Protection 2016年第13期8卷 1283-1296页

作者： sagar shrestha Puspa L. Adhikari Department of Physical and Environmental and Sciences Texas A&M University-Corpus Christi Corpus Christi TX USA Department of Environmental Sciences Louisiana State University Baton Rouge LA USA

Taudaha Lake is one of the important wetlands in Nepal, as it provides critical habitats for thousands of migratory birds and fishes. Despite being a critically important water body, there is a lack of detail chemical and biological studies on this lake. The present study investigates the effects of seasonal water quality variations in distribution and abundance of macroinvertebrates in Taudaha Lake, during four different seasons in 2006. The results indicate that all the water quality parameters, except secchi depth, and total alkalinity, significantly varied among seasons. The gross primary productivity of the lake also significantly varied among the seasons, with highest primary production during summer (3.92 ± 0.18 gC/m3/day) and lowest during spring (2.44 ± 0.67 gC/m3/day). A total of 2166 individual benthic macroinvertebrates from 10 families and 7 orders were collected during the study period. Unlike water quality parameters, the macroinvertebrate species composition did not vary significantly among the seasons. The results suggested that the change in lake water quality did not have significant impacts on community metrics such as species diversity, species richness, and species evenness.

关键词： Taudaha Lake Water Quality Macroinvertebrates Productivity

Determination of Significance of Environmental Impacts of Development Projects: A Case Study of Environmental Impact Assessment of Indrawati-3 Hydropower Project in Nepal

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Journal of Environmental Protection 2011年第8期2卷 1021-1031页

作者： Ram B. Khadka Ajay Mathema Uttam sagar shrestha 不详

The environmental impacts are commonly quantified in the EIA studies by rating, ranking and scaling. The National EIA Guidelines, 1993, Nepal provides a guideline to score the impacts in terms of magnitude, extent, and duration. This step is commonly known as impact prediction in the EIA process. The predicted scores are multiplied by the weightage value of the resource;likely to be affected. The application of the weightage transforms the predicted values of the impacts into their “significance”—a concept used in the environmental decision making. In other words the significance value entails assignment of relative judgment values to the impacts. The impacts, thus, can ranked based on their significance. The impact ranking is more useful in evaluating the socio-economic impacts. Unlike air, water and noise quality, which can be assessed against established standards;the socio-economic impacts do not have standard scale and are difficult to rank. Importance weighting of socio-economic impacts are commonly determined by the consensus obtained from the interaction with the local people, agencies, NGOs and experts. The impact ranking in the EIA process is unavoidable, firstly to prioritize the urgent environmental issues and design mitigation measures accordingly and also provide coherent linkages among the issues, and plan monitoring and auditing linkage with the proposed mitigation measures. Furthermore, it also provide strong basis of decision making, and thus facilitate the decision makers. The process of impact prediction, determination of significance and ranking were applied in the EIA of Indrwati-3 Hydroelectric Project, which is one of the successful cases of EIA in Nepal. The authors believe that the impacts predicted and quantified through this method are being focussed to more on the local concerns, since it seeks an active involvement of the local people who are likely to be affected.

关键词： Environmental Impact Assessment Environmental Significance Ranking Prediction of Impacts Importance Weighting Judgment Values

Evaluation of Spatial-Temporal Variations of Water Quality and Plankton Assemblages and Its Relationship to Water Use in Kulekhani Multipurpose Reservoir, Nepal

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Journal of Environmental Protection 2017年第11期8卷 1270-1295页

作者： Puspa L. Adhikari sagar shrestha Wokil Bam Lin Xie Peter Perschbacher Department of Environmental Sciences Louisiana State University Baton Rouge USA Department of Physical and Environmental Sciences Texas A & M University-Corpus Christi Corpus Christi USA Department of Oceanography and Coastal Sciences Louisiana State University Baton Rouge USA Aquaculture/Fisheries Center University of Arkansas at Pine Bluff Pine Bluff USA 210 River Gate Lane Wilmington USA

Spatial and temporal variation in planktons and water quality parameters were investigated in order to determine the effects of seasonal water use on reservoir water quality and planktons’ diversity in Kulekhani Multipurpose Reservoir, Nepal. This study also focuses on interactions among various water quality parameters with planktons and how such interactions can affect the second major utility, the fish farming in the reservoir. The analyses of seasonal water samples collected from three different sampling locations in the reservoir showed that select water quality parameters varied significantly (P < 0.05) with sampling seasons (transparency: 30 - 250 cm, pH: 7 - 7.5, alkalinity: 30 - 120 mg/L, DO: 6 - 11.5 mg/L, CO2: 0.1 - 1.1 mg/L) and sampling locations (phosphate: 0.1 - 0.25 mg/L, nitrate 0.01 - 0.19 mg/L) in the reservoir. Three groups of zooplankton and four classes of phytoplankton, respectively with eleven and twelve genera, were identified and quantified in the reservoir. Among them, Cyclops, Asplanchana, and Keratella were most dominant zooplanktons while Synedra, Melosira and Peridinum were the most dominant phytoplankton in the reservoir water. The abundance of select zooplanktons (Cyclops, Keratella, Polyanthra), and phytoplankton (Navicula, Melosira, Amphora, Chroococcus, Staurastrum, Scendesmus) showed significant interaction between sampling sites and sampling seasons, while the other varied only with sampling seasons and/or sites. These results showed that seasonal water level fluctuations, along with the variation of water quality parameters, change the abundance and diversity of planktons’ in the reservoir. Such changes can negatively impact the fish in cage culture, affecting the livelihood of people extensively relying on these fish farming.

关键词： Kulekhani Multipurpose Reservoir Water Quality Planktons Aquaculture Cage Culture Hydroelectric Reservoir in Nepal

Validation of the Satellite-Derived Rainfall Estimates over the Tibet

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Acta meteorologica Sinica 2011年第6期25卷 734-741页

作者：除多普布顿珠罗布坚参 sagar Bajracharya MANDIRA shrestha 郭建平 Institute of Plateau Meteorology CMA Tibet Institute of Plateau Atmospheric and Environmental Sciences Tibet Weather Observatory Tibet Meteorological Service International Centre for Integrated Mountain Development (ICIMOD) Chinese Academy of Meteorological Sciences CMA

Measuring rainfall from space appears to be the only cost effective and viable means in estimating regional precipitation over the Tibet, and the satellite rainfall products are essential to hydrological and agricultural modeling. A long-standing problem in the meteorological and hydrological studies is that there is only a sparse raingauge network representing the spatial distribution of precipitation and its quantity on small scales over the Tibet. Therefore, satellite derived quantitative precipitation estimates are extremely usefill for obtaining rainfall patterns that can be used by hydrological models to produce forecasts of river discharge and to delineate the flood hazard area. In this paper, validation of the US National Oceanic and Atmospheric Administration （NOAA） Climate Prediction Center （CPC） RFE （rainfall estimate） 2.0 data was made by using daily rainfall observations at 11 weather stations over different climate zones from southeast to northwest of the Tibet during the rainy season from 1 June to 30 September 2005 and 2006. Analysis on the time series of daily rainfall of RFE-CPC and observed data in different climate zones reveals that the mean correlation coefficients between satellite estimated and observed rainfall is 0.74. Only at Pali and Nielamu stations located in the southern brink of the Tibet along the Himalayan Mountains, are the correlation coefficients less than 0.62. In addition, continuous validations show that the RFE performed well in different climate zones, with considerably low mean error （ME） and root mean square error （RMSE） scores except at Nielamu station along the Himalayan range. Likewise, for the dichotomous validation, at most stations over the Tibet, the probability of detection （POD） values is above 73% while the false alarm rate （FAR） is between 1% and 12%. Overall, NOAA CPC RFE 2.0 products performed well in the estimation and monitoring of rainfall over the Tibet and can be used to analyze the precipitation pattern,

关键词： precipitation validation satellite rainfall estimation Tibetan Plateau

GeoSFM水文模型在西藏拉萨河流域的应用

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山地学报 2015年第6期33卷 751-758页

作者：除多达平向莉英罗布坚参 shrestha Mandira Bajracharya sagar 中国气象局成都高原气象研究所拉萨分部西藏高原大气环境科学研究所西藏自治区水文水资源勘测局西藏自治区气象台国际山地综合发展中心(ICIMOD)

基于物理过程的半分布式水文模型USGS Geo SFM(Geospatial Stream Flow Model)对拉萨河2005年1—12月日径流量进行了模拟,并与同期的观测资料进行了对比。结果表明,Geo SFM模型在拉萨河流域的模拟效果较好,Nash-Sutcliffe效率系数为0.72... 详细信息

基于物理过程的半分布式水文模型USGS Geo SFM(Geospatial Stream Flow Model)对拉萨河2005年1—12月日径流量进行了模拟,并与同期的观测资料进行了对比。结果表明,Geo SFM模型在拉萨河流域的模拟效果较好,Nash-Sutcliffe效率系数为0.72,模拟和观测值之间的线性相关系数达0.89。由于Geo SFM模型输入参数较少,很多可以从应用广泛的全球或大尺度数据中获取,尤其是卫星遥感降水估算产品直接可以作为模型的降水驱动参数,所以在没有或缺少水文气象观测资料的地区应用前景广阔。

关键词：水文模型 GeoSFM 拉萨河西藏

澜沧江和怒江流域的气候变化及其对径流的影响

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气候变化研究进展 2017年第4期13卷 356-365页

作者：刘苏峡丁文浩莫兴国王盛刘昌明罗贤何大明 sagar Ratna Bajracharya Arun Bhakta shrestha Nand Kishor Agrawal 中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 中国科学院大学资环学院/中丹学院北京100049 云南大学昆明650091 International Centre for Integrated Mountain Development Kathmandu 100023Nepal

采用VIP(Vegetation Interface Processes)模型和HIMS(Hydro-Informatic Modeling System)模型,模拟分析了1957—2012年澜沧江和怒江流域(简称两江流域)水资源量的演变。根据CMIP5 RCP2.6,RCP4.5和RCP8.5情景预测,模拟了2030年代和2050年代流域水资源的变化。研究发现,过去50年间,两江流域的气温都呈升高趋势,但海拔较高的上游地区升幅大于下游。年总降水量的变化趋势不明显,但春季降水增加趋势明显。两江流域年总水资源量为650亿~850亿m^3,水资源总量长期变化趋势不明显,其中澜沧江的波动性(1.884,最大与最小之比)大于怒江。空间上水资源量呈现北低-南高的格局。在未来,两江流域气温仍呈增加趋势,降水呈增加趋势,径流呈增加趋势,空间变异性趋小,但较强的季节性变化对水资源安全仍具有较大的挑战性。

关键词：径流气温降水 VIP模型 HIMS模型

Pharmacognostic studies of insect gall of Quercus infectoria Olivier(Fagaceae)

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Asian Pacific Journal of Tropical Biomedicine 2014年第1期4卷 35-39页

作者： Savitri shrestha Vasuki Srinivas Kaushik Ravi Shankara Birur Eshwarappa Sundara Rajan Subaramaihha Latha Muuaiah Ramanna Dhananjaya Bhadrapura Lakkappa Department of Chemistry SBMJCJain University National Referral Centre for Lead Projects in India(NRCLPI) Research Unit in Vrukshayurveda A division of Centre for Advanced Studies in BiosciencesJain University Dayananda sagar College of Applied Science Kumarswamy layout Toxinology Lab School of Chemical and Biotechnology(SCBT)SASTRA University

Objective:To study the detailed pharmacognostic profile of galls of Quercus infectoria Olivier(*** olivier)(Fagaceae),an important medicinal plant used in the Indian system of ***:Samples of galls of *** were studied by macroscopical,microscopical,physiochemical,*** analysis and othjer methods for standardization as recommended by ***:Macroscopically,the crude drug is globose with horny appearances on external surface(1.4-2.3 cm in length and 1-1.5 cm in diameter),with greyish-brown to brownish-black in colour externally and dark brown buff *** is smooth with numerous horny protuberances giving rough touch,and witfi unpleasant ***,a wide zone of radially elongated parenchyma cells between upper and lower epidermis were *** vascular strands were present at all places and radially elongated sclerides touched the lower *** physico-chemical studies,the moisture,total ash,acid insoluble ash,alcohol soluble,water soluble,petroleum ether,chloroform extractive value and tannin content were found to be 2.790,5.020,0.110,38.780,41.210,0.402,1.590 and 49.200 percentage *** phytochemical screening showed the presence of phenols,flavonoids,steroids,triterpenes,tannins,saponins and ***:The results of the present study serve as a valuable source of information and provide suitable standards for identification of this medicinally important plant drug material for future investigations and applications.

关键词： Quercus infectoria Gall extracts Traditional medicine Pharmacognostic study Microscopic studies.