微型生态系统中正磷酸盐的周转时间的估算
ESTIMATION OF THE TURNOVER TIME OF ORTHOPHOSPHATE IN FRESHWATER MICROCOSMS
-
摘要: 在考查罗非鱼或鲢、鳙下行影响的微型生态系统实验后期,以水柱正磷酸盐(PO4-P)完全被浮游植物摄取所需要的时间为指标,估算了系统中PO4-P的周转时间,其中浮游植物的PO4-P摄取率是采用挂瓶法来测定和估算的。结果表明,两组实验中大多数有鱼系统的浮游植物PO4-P摄取率都显着地比无鱼系统高,而PO4-P周转时间的估算值均最着地小于无鱼系统。经相关分析测定,两组实验中浮游植物的PO4-P摄取率皆显着地正相关于浮游植物密度和初级生产力,同水柱PO4-P浓度之间的负相关关系则不显着。根据估算结果看来,罗非鱼对系统中磷循环速率的影响比鲢、鳙大得多,而鳙的影响又明显地大于鲢。这些鱼类使微型生态系统中PO4-P的周转时间缩短,可能主要是它们加速了系统中PO4-P再生的结果。
-
关键词:
- 微型生态系统 /
- PO4－P周转时间 /
- 浮游植物PO4－P摄取率
Abstract: Experiments have been conducted to investigate the effects of Oreochromisniloticus or Hypophthalmichthys molitrix and Aristichthys nobilis on the communitystructure, metabolism and nutrient levels of freshwater microcosms. consultsdemonstrated that in the microcosms stocked with fish, orthophosphate (PO4-P)concentrations were lower but primary productivity was higher than those in thefish-free microcosms, probably indicating an intense cycling of phosphorus in theexperimental microcosms. In the later Period of the experiments, the tUrnover bine ofPo4-P in the microcosms was estimated through the index of the bine required foruptake of the total amount of PO4-P in the water column by phytoplankton, in whichthe PO4-P uptake rate of phytoplankton was eshmated by the decrease of PO4-Pconcentrations in the sample bottles suspended in the microcosms in the given bimeintervals. The results from both experiments showed that the rates of PO4-P uptake byphytoplankton were significantly higher while the indices for PO4-P tUrnover bine weremarkedly lower in most microcosms with fish than those in the fish-free microcosms.In each experiment the rates of PO4-P uptake by phytoplankton were showed to bein significantly posihve correlation with the density and primary preduction ofphytoplankton but in insignificantly negative correlation with PO4-Pconcentrahons inthe water column. It appears that Oreochromis niloticus had much greater influence ascompared witrh Hypophthalmichlhys molilrix and Aristichthys nobilis on phosphoruscycling in the microcosms, whereas the effect of Aristichthys nobilis was obviouslygreater than that of Hypophthalmichthys molitrix. The reduchon of PO4-P turnover timein the microcosms containing fish was attributed mainly to the accelerahon of PO4-Pregeneration by fish. -
-
[1] 阮景荣 刘衢霞 王少梅 等.罗非鱼对微型生态系统浮游生物群落和初级生产力的影响.应用生态学报, 1993, 4(1)：65-73
[2] 阮景荣 戎克文 王少梅.微型生态系统中鲢、鳙下行影响的实验研究．浮游生物群落和初级生产力.湖泊 科学, 1995, 7(3)：226-234
[3] Lynch M. Shapiro J. Predation, enrichment, and phytoplankton community structure. Limnol. Oceanogr., 1981, 26:86-102
[4] Tatrai I. Istvanovics V. The role of fish in the regulation of nutrient cycling in Lake Balaton, Hungary. Freshwat. Biol., 1986, 16:417-424
[5] 阮景荣 刘衢霞 王少梅等.罗非鱼对微型生态系统营养物水平的影响.应用生态学报, 1993, 4(4)：404- 409
[6] 阮景荣 戎克文 王少梅.微型生态系统中鲢、鳙下行影响的实验研究.营养物水平.湖泊科学, 1995, 7(4)：334-340
[7] Peters R H. Concentrations and kinetics of phosphorus fractions in water from streams entering Lake Memphremagog. J. Fish. Res. Board Can., 1978, 35:315-328
[8] Peters R H. Concentrations and kinetics of phosphorus fractions along the trophic gradient of Lake Memphremagog. J. Fish. Res. Board Can., 1979, 36:970-979
[9] 中国医学科学院卫生研究所编.水质分析法.北京：人民卫生出版社, 1974, 112-115
[10] 斯奈迪格G W.等著(杨纪珂 汪安琦译).应用于农学和生物学实验的数理统计方法.北京：科学出版社, 1964, 95-112, 179-215
[11] Reinertsen H. Jensen A. Langeland A. et al. Algal competition for phosphorus: the influence of zooplankton and fish. Can. J. Fish. Aquat. Sci., 1986, 43:1135-1141
[12] Northcote T G. Fish in the structure and function of freshwater ecosystems: a ‘Top-down' view. Can. J. Fish. Aquat. Sci., 1988, 45:361-379
计量
- 文章访问数: 909
- HTML全文浏览量: 0
- PDF下载量: 379
下载: