丹江口水库和干渠南阳段微型生物群落的周期性变化

Periodic Variation of Microbial Communities in Danjiangkou Reservoir and the Water Cancel of Nanyang City Before and After the Start-Up of the Mid-Line Project of South-to-North Water Diversion

旨在掌握南水北调中线工程水源区丹江口水库及南阳段干渠调水前后浮游生物群落结构的动态变化和水质状况,为中线工程调水水质保护和工程管理提供科学依据.于2014年7月-2015年5月分别在中线工程取水口陶岔坝上下游6个监测站进行5次野外调查取样和室内研究.结果显示,共监测到浮游藻类9门44科94属357种(含变种),指示藻类8门21科32属42种(含变种),通水前为β-中污带,调水后为寡污带,调水后硅藻比例明显增加;浮游动物4门32科38属46种;调水后香农-威勒多样性指数均大于1,呈现调水后先降低后增加.丹江口水库及南阳段干渠的水质达到Ⅰ类水质标准(总氮指标除外).综合评价水源区水体稳定,为β-中营养型,符合中线工程调水的水质要求.

In order to understand the dynamic changes of the plankton community structure and water quality of Danjiangkou reservoir and water channel in Nanyang before and after the water transfer of the mid-line project of south to north water division, six stations were monitored to provide scientific basis for the water quality protection and engineering management of the mid-line project during 2014.07- 2015. 05. Plankton and physical-chemical indexes were measured. Water samples were collected using standard methods. Saprobic system, trophic status index, and diversity index of Shannon-Weiner were used to evaluate the trophic status. There were 357 species （varieties）, 94 genera and 9 divisions including 42 species （varieties）, 32 genera saprobic indicators. Samples also contained 46 species （varieties）, and 38 genera of zooplankton occupying 2. 63 %. The proportion of diatom significantly increased after water diversion. Diversity indexes of Shannon- Weiner were above 1.00 in all stations, which went down and then up after the start-up of the mid-line project. The physical-chemical indexes except total nitrogen were under the standard of I type water. All results showed that the nutrition types of the water system could be regarded as mesotrophy, and Danjiangkou reservoir is suitable for the mid-line project.