Streit B
Institute of Limnology, University of Freiburg, Konstanz.
Oecologia. 1976 Sep;22(3):261-273. doi: 10.1007/BF00344796.
Four brook-dwelling populations of Ancylus fluviatilis were studied. Data on life-cycle, specimen number, biomass and egg capsule biomass are reported. By means of experimental data on ingestion, assimilation, growth and egg-production, energy balances are calculated for whole populations.Mean annual biomass turned out to be 26.58-64.88 mg C/m. Mean annual biomass turn-over ratio (production/biomass) was 2.64-5.95. Cohort biomass turnover ratio was 4.11-6.09 for the whole population. Young specimens show considerably higher production efficiencies than adult ones. Production by the smallest size classes is a very considerable part of whole population production. Net production efficiency of the whole population was 11.2-11.8%, gross production efficiency 5.6-6.5%. An important factor for variation between different populations is temperature, but other factors, such as food supply, may be important, too. Experimental production estimates were compaerd with the Allen curve method and the instantaneous growth method.Differences due to different methods of production measurement are discussed. The range of values for different efficiencies lies within the range reported for other freshwater snails. Interpopulation variation in turnover ratios nearly equals variation reported for different species of univoltine snails.
对河流中四个椎实螺种群进行了研究。报告了关于生命周期、样本数量、生物量和卵囊生物量的数据。通过关于摄食、同化、生长和产卵的实验数据，计算了整个种群的能量平衡。年平均生物量为26.58 - 64.88毫克碳/平方米。年平均生物量周转率（产量/生物量）为2.64 - 5.95。整个种群的同龄组生物量周转率为4.11 - 6.09。幼体标本的生产效率比成体高得多。最小尺寸类别的产量占整个种群产量的很大一部分。整个种群的净生产效率为11.2 - 11.8%，总生产效率为5.6 - 6.5%。不同种群之间变化的一个重要因素是温度，但其他因素，如食物供应，可能也很重要。将实验性生产估计值与艾伦曲线法和瞬时生长法进行了比较。讨论了由于不同生产测量方法导致的差异。不同效率的值范围在其他淡水蜗牛报告的范围内。种群间周转率的变化几乎等于单化性蜗牛不同物种报告的变化。
