贵州高原红枫湖水库浮游植物功能分组及其时空分布特征

Phytoplankton functional groups and their spatial and temporal distribution characteristics in Hongfeng Reservoir,Guizhou Province

为了解贵州高原水源红枫湖水库的浮游植物功能类群及其时空分布特征,于2012年至2013年枯水期(11月)、平水期(4月)、丰水期(7月)对红枫湖浮游植物与水体进行分层采样分析。研究结果表明,水库浮游植物可分为25个功能群,其中S1、F、J、B、D、S2、Y、LM是红枫湖主要代表性功能群,而W1、A、W2、K、X3出现频率较低,主要功能群生境特征都适应于中富营养水体,S1适应于透明度较低、混合程度较高的中富营养水体,F适应于深层混合的中至富营养湖泊,J适应于混合的高富营养浅水水体,B对分层敏感适应于中营养水体;各采样点主要浮游植物功能群季节变化大体相同,枯水期、平水期各采样点功能群较少,丰水期功能群最为丰富;水温是影响红枫湖浮游植物功能类群分布变化的主要因子;浮游植物生长策略变化规律为:枯水期CR/R/S策略藻种→平水期R/CR/CS策略藻种→丰水期R/CR/CRS/C策略藻种,水体浮游植物优势功能群在物质供给、能量输入均较理想的条件下能充分生长,随着能量限制程度的增加而较其他类群更具耐受性;通过浮游植物功能群与水体环境相互关系可以得出:红枫湖水体处于中富营养状态。

Hongfeng Reservoir is located at Guizhou Province, which has the most widely distributed and the most complex types of karst. The reservoir is one of the sources for drinking water for Guiyang city. Besides, it has many other functions, such as agricultural irrigation, flood control, and tourism. Management of the eeo-environment and water resources of this reservoir are important for sustainable development of this area. This study identified functional groups of phytoplankton to understand the distribution patterns of the Hongfeng Reservoir, which is different from the traditional approach of community identification. Phytoplankton and water samples were collected in dry period （November 2012 ）, level period （April 2013 ）, and flood period （July 2013）. In total, 25 functional groups of phytoplankton were identified, wherein, the groups S1, F, J, B, D, S2, Y, and LMwere comparatively common functional groups, and the groups W1, A, W2, K, and X3 were less common. Habitat characteristics of the main functional groups that are adapted to the eutrophication of water bodies included eodon S1 habitat template： turbid mixed environments, eodon F habitat template： clear, deeply mixed mesoeutrophic lakes, eodon J habitat template： shallow, mixed, highly enriched systems （including many low-gradient rivers）, eodon B habitat template： mesotrophie small- and medium-sized lakes with species sensitive to the onset of stratification. The seasonal changes among the three sampling sites were generally the same. During dry period and level period of phytoplankton functional groups of each site is less, the plentiful functional group of the largest number in the wet period. The dry period, level period, and wet period have 16, 19, and 22 function groups, respectively. The main representative functional groups are J/B/P for dry period, S1/J/B/F for average water season, and S1 （dominant functional group）/D/J for wet period. Phytoplankton functional groups changed at depth of 6 m for Jiangjunwan and Houwu, and at depth of 10 m for Dam. In addition, the analysis of changes in the environmental factors suggested that water nutrient is no longer the limiting factor for the phytoplankton growth, and that water temperature is the most important factor influencing the spatial and temporal distribution of the phytoplankton functional groups. The strategy of the phytoplankton growth followed the law ： CR/R./S in dry period→ R/CR/CS in level period → R/CR./CRS/C in wet period （C means Competitors; R means Ruderals; S means Stress-tolerators ）. Phytoplankton functional groups can grow well under ideal conditions of material supply and energy input. The phytoplankton functional groups increased with the increase in the degree of energy restriction and were more tolerant than other groups. It could be concluded that I-Iongfeng Reservoir is in the meso-eutrophic state based on the correlation of phytoplankton functional groups and aquatic environment.