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1.
为了确定百花水库营养盐变化特征,选取百花水库5个监测点2014年1月-2018年7月共28个月份的水质实测数据,分析溶解氧、高锰酸盐指数、氨氮、总磷和总氮的年际变化特征.采用基于熵权法赋权的贝叶斯理论对5个监测点的水质综合状况进行评价,并结合水库的实际状况,从生态修复、工业污染源、沉积物中营养盐、水库季节性热分层及农业与生活污染源5个方面对其水质变化的影响因素进行分析.结果表明:2014-2018年水体环境波动较大;除总氮外,各污染指标浓度均有不同程度的下降;综合水质后验概率表明百花水库水质有逐渐变差的趋势;总氮和总磷治理应成为百花水库污染治理的主要方面;生态修复工程的开展和工业污染源的削减是百花水库水质转好的主要影响因素,农业与生活污染源的增加是百花水库水质转差的主要影响因素.  相似文献   
2.
为了解黔中地区浮游植物群落结构特征,同时为了研究功能群对水环境的指示,选取黔中2座典型水库——普定水库和桂家湖水库,分别于2015年的枯水期(1月)和丰水期(8月)进行浮游植物采样分析.结果表明:(1)2座水库营养盐无显著性差异,水动力学参数(水温、混合层深度、透明度、真光层深度、水柱相对稳定性、光的可获得性)存在显著性差异.(2)普定水库共归类出18个功能类群,桂家湖水库共归类出15个功能类群.普定水库优势功能群水期分布特征:枯水期LO→丰水期B+P;桂家湖水库优势功能群水期分布特征:枯水期B+J+Y→丰水期B+J.垂直层面上,普定水库枯水期以甲藻组成的优势功能群LO在三岔街采样点表层藻类生物量达到峰值(18529μg/L),远高于中层和底层水体以及其他采样点,与该点水文特性以及组成LO的甲藻特征有关.丰水期以硅藻组成的功能群P在小河采样点的中层藻类生物量最大(2741μg/L),远高于该点的表层水体及其他采样点,与P类群耐受低光有关.而桂家湖水库由于面积小、水位浅且少有人为干扰,故样点间环境因子差异小,整个水体优势功能群分布高度一致.(3)经RDA分析,水动力学参数、营养盐、p H和电导率是影响普定水库浮游植物群落分布的主要环境因子;桂家湖水库仅水动力学参数(水温和水柱相对稳定性)是主要因子.(4)从浮游植物功能群适宜生境来看,普定水库为富营养水体,桂家湖水库为中到富营养水体.由分析得出隶属于不同水域的2座水库浮游植物群落结构及水环境均存在显著性差异.  相似文献   
3.
我国近些年加快了不动产登记与交易系统的监管力度,而不动产信息的登记与信息整理技术应用还需进一步完善与提升。对不动产登记的相关整合技术进行研究探讨具有现实指导意义。  相似文献   
4.
为了能够准确、快速、大范围地对湖泊富营养化进行监测评价,以贵阳市百花湖为实例,首先,对其水体进行光谱实测与水体采样实验,以及对水体光谱进行归一化、一阶微分、二阶微分等处理,诊断各水质参数的敏感波段,建立其水质参数的高光谱遥感定量模型;其次,探讨湖泊水质高光谱反射率与水质参数浓度之间的定量关系,并采用综合营养状态指数法(TLI)对百花湖富营养化进行评价。结果表明:(1)利用水体光谱的一阶微分反射率分析光谱与水质参数之间的相关性,得出水质参数(Chl-a、TP、TN、SD、CODMn)的敏感波段分别为699nm、823nm、399 nm、563nm、504nm;(2)利用水质参数敏感波段对湖泊水质参数进行估测的效果较为理想,各估测模型R2分别达到0.8276、0.7711、0.7917、0.9213、0.8328;(3)采用水质参数的实测值与估测值对百花湖富营养化评价结果是一致的,且均为中营养化,说明采用高光谱技术对湖泊富营养化的监测与评价是可行的。  相似文献   
5.
为了探明百花湖麦西河后生浮游动物的群落组成及动态特征,于2009年8月至2011年8月对百花湖麦西河河口后生浮游动物进行调查研究.结果表明:百花湖麦西河河口共监测到轮虫29种,丰度为0.16~837.80 ind./L;桡足类浮游动物仅检测到了温中剑水蚤(Mesocyclops thermocyclopoides)和猛水蚤(Harpacticella sp.)2种,以无节幼体和桡足幼体为主,其丰度为0~642.75 ind./L;枝角类浮游动物9种,丰度为0~31.20 ind./L.后生浮游动物的丰度主要由轮虫和桡足类组成,轮虫丰度比例为4.09%~100%,桡足类丰度比例为0~95.64%.前节晶囊轮虫(Asplanchna priodonta)、卜氏晶囊轮虫(Asplanchna brightwelli)、裂足臂尾轮虫(Brachionus diversicornis)为轮虫类的主要优势种,最高丰度分别达到424.88、392.20和61.99 ind./L;长额象鼻溞(Bosmina longirostris)为枝角类优势种,最高丰度达到27.93 ind./L.轮虫丰度与透明度、总氮、硝态氮呈极显著正相关;枝角类丰度与透明度、硝态氮呈极显著正相关,与温度呈极显著负相关.  相似文献   
6.
Phytoplankton and environmental variables were measured monthly from July 2009 to August 2011 in the Maixi River from the estuary to Baihua Reservoir in the Maotiao River catchment,southwestern China,to understand phytoplankton community structure and environmental factors.The relationship between phytoplankton community structure and environmental factors including hydrological,meteorological,physical,and chemical variables were explored using multivariate analysis.A total of 81 taxa of phytoplankton were identified,which were mainly composed of chlorophyta,bacillariophyta,and cyanobacteria.The phytoplankton community was dominated by Pseudanabaena limnetica during summer and fall and by Cyclotella meneghiniana during winter and spring.The abundance of phytoplankton ranged from 0.24×104 cells/L to 33.45×106 cells/L,with the minimum occurring during February 2010 and the maximum during July 2009.The phytoplankton community was dominated mainly by cyanobacteria from April to September,and by bacillariophyta and pyrrophyta from October to March.Canonical correspondence analysis showed that temperature,pH values,and orthophosphate were the most important driving factors regulating the composition and dynamics of the phytoplankton community in the estuary.Cyanobacteria and euglenophyta abundance and biomass were affected mainly by temperature and pH values,while most chlorophyta and bacillariophyta were influenced by the concentrations of nutrients.  相似文献   
7.
Phytoplankton and environment factors were investigated in 2015 and phytoplankton functional groups were used to understand their temporal and spatial distribution and their driving factors in Wanfeng Reservoir. Seventeen functional groups(B, D, E, F, G, J, Lo, MP, P, S1, T, W1, W2, X1, X2, Xph, Y) were identified based on 34 species. The dominant groups were: J/B/P/D in dry season, X1/J/Xph/G/T in normal season and J in flood season. Phytoplankton abundance ranged from 5.33×10~4 cells/L to 3.65×10~7 cells/L, with the highest value occurring in flood season and lowest in dry season. The vertical profi le of dominant groups showed little differentiation except for P, which dominated surface layers over 20 m as a result of mixing water masses and higher transparency during dry season. However, the surface waters presented higher values of phytoplankton abundance than other layers, possibly because of greater irradiance. The significant explaining variables and their ability to describe the spatial distribution of the phytoplankton community in RDA diff ered seasonally as follows: dry season, NH4-N, NO_3-N, NO_2-N, TN:TP ratio and transparency(SD); normal season, temperature(WT), water depth, TN, NH4-N and NO_3-N; flood season, WT, water depth, NO_3-N and NO_2-N. Furthermore, nitrogen, water temperature, SD and water depth were significant variables explaining the variance of phytoplankton communities when datasets included all samples. The results indicated that water physical conditions and hydrology were important in phytoplankton community dynamics, and nitrogen was more important than phosphorus in modifying phytoplankton communities. Seasonal differences in the relationship between the environment and phytoplankton community should be considered in water quality management.  相似文献   
8.
为探究宜昌长江南岸岩溶区地下水中水生动物群落分布特征及环境响应规律,在2018年7月至8月对宜昌长江南岸15处表层岩溶泉及9处岩溶大泉中水生动物进行采集,同时对地下水理化指标进行测试。共采集到809个动物个体,共有13个亚纲,同时包括多个物种的暗层和非暗层种。结果发现:①不同动物在地下水空间分布上各异,在表层岩溶泉,Copepoda的暗层种和Ostracoda的暗层种大量存在(31.3%, 23.7%),Trichoptera和Diptera少量存在(0.4%, 2.9%);在岩溶大泉,Copepoda(非暗层种)和Amphipoda大量存在(25.0%, 8.3%),Ostracoda的暗层种少量存在(2.2%)。②不同地下水的环境也表现出差异,区内岩溶大泉pH, Na+, Ca2+, Mg2+等指标的极差(分别为0.64, 1.25, 34.0, 22.1 mg/L)小于表层岩溶泉(分别为2.45, 5.68, 59.6, 33.4 mg/L),表现出更稳定的环境特征。③通过对各环境因子以及不同物种的逐步回归分析得出,表层岩溶泉的主控环境因子为pH, Na+, Mg2+,岩溶大泉的主控环境因子为pH, SO42-, Mg2+;表层岩溶泉的主要代表性生物群落为Ostracoda, Diptera, Turbellaria的暗层物种,岩溶大泉的主要代表性生物群落为Mollusca, Diptera, Decapoda。④通过路径分析发现,生物通过种间相互作用,对环境因子具有直接与间接响应。在表层岩溶泉,Diptera主要通过与Ostracoda的种间关系对Na+和Mg2+起间接响应,另外Ostracoda, Diptera, Turbellaria的暗层种对pH有直接响应;在岩溶大泉,Mollusca主要通过Diptera对pH起间接响应,Diptera通过Decapoda对SO42-起间接响应,另Mollusca, Diptera, Decapoda对Mg2+直接响应。研究发现生物分布规律是对于环境因子的直接作用和生物之间的间接作用共同响应结果。   相似文献   
9.
Toxic cyanobacteria(TCB) are well-known worldwide for their adverse impacts on humans. Species compositions and seasonal variations of TCB in reservoirs depend on interactions between physical and chemical factors. This study was conducted to evaluate the water quality in the Aha Reservoir, Southwest China, focusing on cyanobacteria and cyanotoxins. Water samples were collected weekly or biweekly from May to September of 2015 and used to delineate temporal variations in density and distribution of toxic cyanobacteria and cyanotoxins in the reservoir. Toxic cyanobacteria identified consisted of Aphanizomenon flos-aquae, Pseudanabaena limnetica, Cylindrospermopsis sp., and Microcystis sp., with Aphanizomenon flos-aquae and Pseudanabaena limnetica being the most common and significant toxic genera. The total biomass of cyanobacteria was 17.0 mg/L. Identification and quantification of microcystin variants were conducted by high performance liquid chromatography(HPLC) using a system equipped with a photodiode array detector. Microcystin levels were between 0–3.0 μg/L, MC-RR was around 0–3.0 μg/L and MC-LR was approximately 0–0.9 μg/L. Overall, the results of this study indicate that the investigated reservoirs should be monitored regularly to minimize potential health risks to the human population.  相似文献   
10.
为了解贵州高原花溪水库在2017年3月生态调控蓝藻水华后,浮游植物物种多样性结构的稳定状况,于2017年4月2018年1月4个季节对花溪水库的浮游植物群落结构进行调查.运用生态位宽度、生态位重叠值、方差比率法、卡方检验和联结系数对主要浮游植物群落间的相互关系进行综合分析.结果表明:4个季节共出现优势种4门11种,其中硅藻门的尖针杆藻(Synedra acusva)和梅尼小环藻(Cylotella meneghiniana)在4个季节都为优势种,对水环境状态指示明显.各优势种的生态位宽度差异较大,变化范围为0.120~0.814,主要由广生态位种和窄生态位种组成.种对间生态位重叠值的变化范围为0.101~0.936,生境越相似的种对重叠值越大.方差比率法结果分析显示,优势种对间总体呈显著正关联.通过卡方检验后发现38对藻种中联结性显著的有9对,主要分布在夏、秋季,体现了花溪水库群落结构受人为干扰和季节变化的影响较大,呈"不稳定-稳定-不稳定"的交叉演替模式.  相似文献   
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