单 位：
贵州师范大学贵州省山地环境信息系统和生态环境保护重点实验室;山地生态与农业生物工程协同创新中心;贵州大学生命科学学院;贵州大学林学院;贵州大学动物科学学院
关键词：
草海;水质变化;水质分区;喀斯特高原;高原湿地
摘 要：
针对草海水质污染状况,开展水质季节变化特征研究,为草海湿地污染治理及保护提供依据。在草海湿地湖泊设置了15个采样点,于2014年8月、11月和2015年1月、4月,分4季进行水样采集。以所测水质参数为基础,运用水质综合评价和GIS空间分析方法,研究草海湿地水环境质量时空变化,并基于营养状态对湖泊水体进行了分区。研究表明:(1)草海TP、TN、CODMn、Chl-a 4种主要水质指标浓度在春季高于其他3个季节,浓度分别达到0.03、0.98、6.30和0.025 mg/L,空间分布呈现由东至西逐渐降低的趋势,草海入水口及码头区域要明显高于湖泊其他区域。(2)草海湖泊营养状态为中营养级别,按4个季度的综合营养状态指数(TLI)平均值分为3个区域,A区为东北角入水口及西海游客码头,长年处于富营养状态,为富营养状态区,53.9≤TLI≤63.0,水质处于Ⅳ与Ⅴ类等级;B区为临近县城及入水口区域,季节性富营养状态,为中营养状态区,41.2≤TLI≤46.6;C区为草海湖泊中心延续到阳关山的下游出水口区域,为贫中营养状态区,35.8≤TLI≤39.7;B区和C区水质全年为Ⅲ类等级。(3)各区域主要污染物指标以Chl-a、TN为主,A区形成的主因是城市污水注入,B区形成的主因是农业面源污染。控制城市污水和农药、化肥施用量是治理草海湖泊水环境的重要途径。
译 名：
Spatial-temporal Variation of Water Quality in Caohai Lake
作 者：
ZHOU Chen;YU Li-fei;CAI Guo-jun;AN Miao;XIA Pin-hua;College of Forestry,Guizhou University;College of Life Sciences,Guizhou University;Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering;College of Animal Sciences,Guizhou University;Guizhou Key Laboratory for Mountainous Environment Information and Ecological Protection,Guizhou Normal University;
关键词：
Caohai Lake;;water quality variation;;area division;;karst plateau;;plateau wetland
摘 要：
Caohai Lake,located on the Guizhou karst plateau,is one of the three great plateau freshwater lakes in China and it plays an important role in the Caohai Wetland ecosystem,part of the National Nature Reserve of Caohai,Guizhou Province. The total area of the wetland is 96. 0 km2,with a water area of 19. 8 km2 in dry season and26. 0 km2 in wet season. A seasonal investigation of water quality in Caohai Lake was carried out to reveal the factors influencing lake water quality and provide a scientific basis for pollution control and conservation of Caohai Lake and Wetland. Water samples were collected once during each season( August and November,2014 and January and April,2015) at 15 sampling sites. Water temperature,depth,transparency,dissolved oxygen and p H were measured in situ using a WTW 3430 water quality analyzer. Total nitrogen( TN),total phosphorus( TP),permanganate index( CODMn) and Chl-a were determined using standard analytical methods. The resulting data was used to assess spatial-temporal variations of Caohai water quality using GIS analysis. Results show:( 1) Concentrations of TN,TP,CODMnand Chl-a were higher in spring than other seasons: 0. 98 mg / L,0. 03 mg / L,6. 30 mg / L and 0. 025 mg / L,respectively. Spatially,TN,TP,CODMnand Chl-a concentrations decreased gradually from east to west,being generally higher at the inlet and wharf than other areas of the lake.( 2) Overall,the trophic status of Caohai Lake is mesotrophic,but the 15 sampling sites fell into three groups according to the average comprehensive trophic status index( TLI) across the four seasons. Area A includes the inlet and tourist wharf of northeastern Caohai,which remained eutrophic throughout the year( 53. 9 ≤TLI≤63. 0) and water quality remained at the level of IV to V. Area B,including the areas located near Weining County and water inlet,is mesotrophic with seasonally eutrophic conditions( 41. 2≤TLI≤46. 6). Area C,from the center of the lake to the outlet near Yangguang Mountain,is oligo-mesotrophic( 35. 8≤TLI≤39. 7). Water quality in areas B and C are both level III.( 3) Chl-a and TN were the major contributors to the TLI scores in all three areas. Municipal wastewater was the principal cause of poor water quality in Area A and agricultural non-point source was the principal nutrient source to Area B. Therefore,controlling municipal wastewater discharge and over-use of chemical fertilizers are key for improving water quality in Caohai Lake.
