Experimental Analysis of Deformation Characteristic for Soil Bank Slope Under Reservoir Water Level Fluctuation

Under reservoir water level fluctuation, soil bank slope water sucking, stress concentration and slip deformation in Three Gorges Reservoir area form slope cracks system at different periods and different spatial parts. In this study, laws of cracks spatial evolution in different deformation periods for soil bank slope were analyzed during a water cycle of impoundment and decline by model test. The test results indicated that, in the initial impoundment period, cracks appeared near the water line at the bank slope leading edge with high appearance frequency, and scale increased gradually and partial bank slope collapsed and damaged. In the middle impoundment period, cracks appeared in the front and trailing edges of bank slope, the frequency of occurrence and the scale of which decreased. And in the late impoundment period, the leading edge of the cracks development disappeared, the trailing edge of the cracks continued to develop and the bank slope crept along the sliding surface as a whole. Cracks expanded slowly in the pause impoundment as the water level raised. In the water level decline stage, tensile cracks mainly occurred in the back edges of bank slope. In the early water level decline, cracks appeared in low frequency and it grew slowly. In the late water level decline, cracks appeared in high frequency and large scale, and where the bank slope produced lower seat deformation and dislocated berm. Moreover, in water level decline stage, bank slope crept along the sliding surface as a whole.     

二龙山水库水质变化趋势评价研究

采用灰色理论对二龙山水库水质变化趋势进行评价,考虑相关因素选取高锰酸盐指数、BOD5、总氮和总磷作为水库的主要污染因子。通过1996～2003年污染因子的权重系数ei计算表明,二龙山水库的主要污染物是氮和磷,属有机污染型。据模糊综合指数zj评价二龙山水库1996～2003年历年水库水质变化,表明二龙山水库水质质量在已有的8年期间有所下降,分析其原因与二龙山水库作为国家4A级旅游区的开放是分不开的。     

泥河水库渔业水域水质及评价

1998年对泥河水库水的理化性状测定、分析,进行评价,为该水库渔业发展提供科学依据。     

三峡库区香溪河流域水沙关系变化及其驱动因素

[目的]分析降水量及水土保持措施等人类活动对流域水沙关系的响应,为水土保持措施效益评价提供科学依据。[方法]以香溪河流域兴山站输沙量数据为基础,采用Mann—Kendall趋势检验、线性回归、水文频率曲线及双累积曲线等方法,分析了1973—2010年香溪河流域面降雨量、径流量和输沙量变化,并进一步量化分析了流域水沙变化极其驱动因素。[结果]香溪河流域年降水量,年径流量和年输沙量均呈下降趋势,年降水量和年径流量变化趋势不显著,但年输沙量减少趋势显著;年输沙显著减少开始的年份是1994年,流域径流量开始减少的年份是1991年。[结论]水土保持等人类活动是香溪河流域水沙变化的主要驱动因素。     

三峡库区土地资源开发对水土流失的影响及其防治对策

该以秭归县为例，充分认识三峡工程的淹占情况及水土流失的现状，并就移民安置区土地资源开发对水土流失的影响，以及如何防止水土流失提出了防治对策。     

三峡水库太湖新银鱼耳石日轮与生长的研究

对采自重庆长江江津江段的太湖新银鱼(Neosalanx taihuensis)耳石日轮与生长进行了研究。太湖新银鱼矢耳石形状近圆形,体长(Y)与耳石长半径(X)之间呈线性相关,其关系式为Y=0.1099X+16.986,R2=0.7626。耳石日轮环纹清晰,以中心核为起点圆形规则排列,其上具有明显的过渡轮纹。太湖新银鱼体长(Y)与日轮(X)呈线性关系,其关系式为Y=0.2631X+23.924,R2=0.8057;体重(Y)与日轮(X)呈指数关系,其关系式为Y=0.0446e0.0244X,R2=0.8104。太湖新银鱼体重(Y)与体长(X)间呈显著的幂函数关系Y=0.000001X3.3529,R2=0.9163。     

Host tropism of infectious salmon anaemia virus in marine and freshwater fish species

The aquatic orthomyxovirus infectious salmon anaemia virus (ISAV) causes a severe disease in farmed Atlantic salmon, Salmo salar L. Although some ISA outbreaks are caused by horizontal transmission of virus between farms, the source and reservoir of the virus is largely unknown and a wild host has been hypothesized. Atlantic salmon are farmed in open net‐pens, allowing transmission of pathogens from wild fish and the surrounding environment to the farmed fish. In this study, a large number of fish species were investigated for ISAV host potential. For orthomyxoviruses, a specific receptor binding is the first requirement for infection; thus, the fish species were investigated for the presence of the ISAV receptor. The receptor was found to be widely distributed across the fish species. All salmonids expressed the receptor. However, only some of the cod‐like and perch‐like fish did, and all flat fish were negative. In the majority of the positive species, the receptor was found on endothelial cells and/or on red blood cells. The study forms a basis for further investigations and opens up the possibility for screening species to determine whether a wild host of ISAV exists.     

天然气库土壤中细菌及甲烷氧化菌的数量分布特性研究

在天然气藏压力的驱动下,天然气藏的轻烃气体持续向地表做垂直扩散和运移,在油气藏正上方的地表土壤中非常发育并形成微生物异常,研究这种异常现象可作为地下轻烃渗漏的指标,对这种高度专属性细菌的检测可为判别土壤中是否存在甲烷提供依据。通过运用传统的稀释涂平板方法对天然气库的0．5m、1．0m、1．5m和2．0m深度土层中微生物数量计数发现,同一采样点位土壤中的细菌数量随着土层的加深而逐渐减少,0．5m浅层土壤中微生物的数量级在10^7,lm、1．5m和2m土层土壤中微生物的数量级在10^6、10^5和10^4;甲烷氧化菌的数量分布规律与此基本相同,0．5m浅层土壤中甲烷氧化菌的数量级在10^5,1m、1．5m和2m土层土壤中甲烷氧化菌的数量级在10^4、10^4和10^3。与对照点对比可知,天然气库土壤中出现了“微生物异常”分布,这种异常分布对评价和预测下伏天然气藏的存在和性质具有直接的现实意义。     

三峡库区防护林不同林分结构森林小气候研究

研究表明：1．中龄林、成熟林对森林小气候影响最大,幼龄林、衰退林影响最小。2．复层混交林＞单层混交林＞单层纯林。并建立了y＝41．3038—9．9219×X_1－0．3002X_2等数学模型。结论：在各林分主要因子中,对森林小气候影响大小排序为：郁闭度＞平均树高＞树冠层厚度等。     

千河冯家山水库淤积数学模型的研究

利用千河千阳水文站1957～1993年的水沙资料及冯家山水库的运用方式,建立了冯家山水库淤积数学模型。在数学模型验证的基础上,得到了冯家山水库未来50年内的淤积过程、淤积总量及分布。其中水库将淤积1.71亿m3,推移质淤积占0.259亿m3,悬移质淤积占1.45亿m3;有效库容由2.86亿m3损失到1.43亿m3,死库容由0.91亿m3损失到0.33亿m3,从而导致冯家山水库调节系数降低,大大减小调节能力。