CAJ | 학술논문

分析了兰州市银滩湿地2011年3?10月沉积物中硅藻群落结构以及演变特征.每月中旬在湿地样点采集8个沉积物样,同时测定样点水体温度、电导率和pH值.共鉴定出27属,126种及变种硅藻, Navicula和Nitzschia 两个属出现的频率最高.各个月份的硅藻优势种、个体形态、种群数量及结构有较大的差异.其中,3月份以Navicula pupula 为优势种,4月份以Navicula simplex 为优势种,5,8,10三个月Navicula veneta在表层沉积物中含量最高,6月份Cymbella pusilla 丰度最高,7,9两个月的优势种为Navicula viridula var. rostellata.而从7月以后湿地硅藻属种的面貌发生了较大的变化, Nitzschia palea, Cymbella a?nis, Cymbella ventricosa, Navicula veneta, Navicula viridula var. rostellata 等成为了主要硅藻属种.受黄河7月以后水位上升的影响,外源污水可能大量进入湿地水体,湿地大部分处于弱有机污染状态.通过对硅藻属种及pH、电导率、总有机质质量分数和温度环境变量之间的去趋势对应分析和主成分分析表明: pH是影响硅藻属种分布最主要的环境变量,能解释较多的硅藻属种分布特征;次要的环境变量是电导率、有机质质量分数受水体的影响,表明湿地水体有机污染物有外源输入的特征.
분석료란주시은탄습지2011년3?10월침적물중규조군락결구이급연변특정.매월중순재습지양점채집8개침적물양,동시측정양점수체온도、전도솔화pH치.공감정출27속,126충급변충규조, Navicula화Nitzschia 량개속출현적빈솔최고.각개월빈적규조우세충、개체형태、충군수량급결구유교대적차이.기중,3월빈이Navicula pupula 위우세충,4월빈이Navicula simplex 위우세충,5,8,10삼개월Navicula veneta재표층침적물중함량최고,6월빈Cymbella pusilla 봉도최고,7,9량개월적우세충위Navicula viridula var. rostellata.이종7월이후습지규조속충적면모발생료교대적변화, Nitzschia palea, Cymbella a?nis, Cymbella ventricosa, Navicula veneta, Navicula viridula var. rostellata 등성위료주요규조속충.수황하7월이후수위상승적영향,외원오수가능대량진입습지수체,습지대부분처우약유궤오염상태.통과대규조속충급pH、전도솔、총유궤질질량분수화온도배경변량지간적거추세대응분석화주성분분석표명: pH시영향규조속충분포최주요적배경변량,능해석교다적규조속충분포특정;차요적배경변량시전도솔、유궤질질량분수수수체적영향,표명습지수체유궤오염물유외원수입적특정.
@@@@Diatom community and structure were analysized in the sediments collected from March to October in the Lanzhou Yintan Wetland. Every mid-month, eight samples in 50 g surface sediments were collected at the same site. Simultaneity, water temperature, conductivity and pH were determined at the sample site. 27 genera, 126 species and varieties of diatom were identified in the Environmental Lab in the College of Earth and Environmental Sciences, Lanzhou University and it was found that Navicula and Nitzschia were the highest concentration among them. Navicula pupula was the dominant species in March, Navicula simplex in April, Navicula veneta in May, August and October, Navicula viridula var. rostellata in July and September. Navi-cymbula pusilla was the dominant species in June. The diatom community characteristics changed greatly after July. Nitzschia palea, Cymbella a?nis, Cymbella ventricosa, Navicula veneta, Navicula viridula var. rostellata became the predominant diatom species. Seen from the diatom community, external organic pollution influenced the water in the Lanzhou Yintan Wetland with rise of the water level of the Yellow River starting from July. The relationship between diatom species and environmental variances such as pH, SC, w(TOC) and temperature was analysised using DCA and PCA methods. The result showed that pH was the primary environmental variance influencing diatom species and next was the conductivity (SC). And the TOC contained in the samples showed that the water was influenced by external orangic pollutions.