Structural and grazing responses of zooplankton community to biomanipulation of some Dutch water bodies
Structural and grazing responses of zooplankton community to biomanipulation of some Dutch water bodies
复制标题
浮游动物群落对荷兰某些水体生物操纵的结构和放牧反应
DOI：
10.1007/bf02530332
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发表时间：
1990
期刊：
影响因子：
2.6
通讯作者：
R. D. Gulati
中科院分区：
文献类型：
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作者：
R. D. Gulati
甲壳类浮游动物的结构和放牧活动进行了比较，在五个湖泊进行操作与几个未经处理的富营养（浅）和中营养（深）湖泊在荷兰。生物操纵的湖泊中轮虫和甲壳类的物种数量和丰度都较少，平均动物大小（3-11 µg C ind.−1）比未操纵的富营养湖泊（0.65 µG C ind. −1）大得多。WhereasD. hyalina（=D. galeata）和D.在未处理的湖泊和处理过的湖泊中，葫芦形藻通常共存。Hyalina和其他大型水蚤、D. magna，D. pulex）;（pulicaria）是重要的食草动物。在生物操纵的湖泊中，个体甲壳动物尺寸和浮游动物质量的增加反映在悬浮物浓度的降低、更高的塞奇盘深度以及蓝细菌浮游植物生物量份额的显着减少。悬浮物（150 µm）和浮游动物之间的生物量关系显示出莫诺型关系，在曲线的初始部分，浮游动物对悬浮物的增加呈线性响应，直到约2 mg C l−1，然后在3-4 mg C l− 1悬浮物时，浮游动物质量达到饱和（0.39 mg C l−1），当悬浮物水平>4 mg C l−1时，浮游动物质量受到抑制。在生物操纵的湖泊中，浮游动物的摄食率在春季经常超过100%d −1，食物水平通常下降到<0.5 mg C l−1。计算出的浮游动物的比清除率（SCR）为1.9 l mg− 1 Zoop C，完全在深营养和中营养沃茨的SCR值（1.7-2.2 l mg− 1 Zoop C）范围内，但比富营养湖泊高出一个数量级，食物水平高出10倍。对于25% d− 1的湖泊悬浮物清除，生物操纵湖泊需要35 - 60 ind. l− 1，而富营养化湖泊需要1200-1300 ind. l − 1。同样，在富营养化湖泊中，要消灭每日初级生产量，需要的甲壳类食草动物比在生物操纵湖泊中多10至15倍。这些数字与动物大小的差异呈负相关。在富营养化沃茨中，清除初级生产力所需的浮游动物生物量值在生物操纵的湖泊中为0.1-0.2 mg C l− 1，而在未操纵的富营养化沃茨中约为0.45 mg C l− 1。然而，大多数情况下，输入超过了浮游动物的同化去除，估计悬浮物损失可归因于沉积和矿化。
Structure and grazing activities of crustacean zooplankton were compared in five lakes undergoing manipulation with several unmanipulated eutrophic (shallow) and mesotrophic (deep) lakes in The Netherlands. The biomanipulated lakes had lesser number of species and their abundance, both of rotifers and crustaceans, and had much larger mean animal size (3–11 µg C ind.−1) than in the unmanipulated eutrophic lakes (0.65 µG C ind.−1). WhereasD. hyalina(=D. galeata) andD. cucullatagenerally co-occurred in the unmanipulated lakes, in the manipulated lakes bothD. hyalinaand other large-bodied daphnids,D. magna,D. pulex(=D. pulicaria), were the important grazers. In the biomanipulated lakes an increase in the individual crustacean size and of zooplankton mass were reflected in a decrease in seston concentration, higher Secchi-disc depth and a marked decrease in the share in phytoplankton biovolume of cyanobacteria. Biomass relationship between seston (150 µm) and zooplankton indicated a Monod type relationship, with an initial part of the curve in which the zooplankton responds linearly to the seston increase up to aboutca.2 mg C l−1, followed by a saturation of zooplankton mass (0.39 mg C l−1) at 3–4 mg C l−1seston, and an inhibitory effect on zooplankton mass at seston levels>4 mg C l−1. This latter is related to predominance in the seston of cyanobacteria.In the biomanipulated lakes, the zooplankton grazing rates often exceeded 100% d−1, during the spring, and food levels generally dropped to <0.5 mg C l−1. The computed specific clearance rate (SCR) of zooplankton of 1.9 l mg−1Zoop C is well within the range of SCR values (1.7–2.2 l mg−1Zoop C) from deep and mesotrophic waters, but about an order of magnitude higher than in the eutrophic lakes, with the food levels 10-fold higher. For 25% d−1clearance of lake seston between 35 and 60 ind. l−1are needed in the biomanipulated lakes against 1200–1300 ind. l−1in eutrophic lakes. Similarly, about 10 to 15 times more crustacean grazers are required to eliminate the daily primary production in the eutrophic lakes than in the biomanipulated lakes. These numbers are inversely related to the differences in animal size. The corresponding biomass values of zooplankton needed to clear the daily primary production in the eutrophic waters were 0.1–0.2 mg C l−1in the biomanipulated lakes, but about 0.45 mg C l−1in the unmanipulated eutrophic waters.Only if the water was kept persistently clear by zooplankton was there a balanced seston budget between the inputviaprimary production and elimination by zooplankton. Mostly, however, the input exceeded the assimilatory removal by zooplankton, such that the estimated seston loss could be attributed to sedimentation and mineralization.