Algal Nutrient Limitation and Food Quality for Aquatic Herbivores

藻类生长的营养限制引起了细胞生化组成的变化。这反过来又影响了藻类作为上层营养层食物的质量。因此，草食动物与其食物相互作用的动力学模型应该包括这种食物质量效应。本研究将探讨藻类生长速度对食品质量的影响。实验室人口统计学研究的淡水枝海，水蚤，取食各种有限的单藻和多藻食物将进行。这些研究将确定简单系统中生长速度和质量之间的关系。此外，食品质量对自然种群的影响将通过一系列实验和测量进行检验，包括1。藻类种群的性质和营养限制程度评估，2。2 .浮游动物种群食物限制程度评价；浮游动物对氮、磷同化效率的测定。这些数据将用于在理论模型中探索草食动物和藻类共存的稳定性和趋势如何受到食品质量效应的影响。研究结果将有助于建立湖沼学的概念基础，并将增加管理水生资源的信息库。

Nutrient limitation of algal growth provokes changes in the biochemical composition of the cells. This in turn affects the quality of algae as food for upper trophic levels. Models of the dynamics of the interaction of herbivores and their food thus should include such food quality effects. This research will explore the ways in which algal growth rate changes food quality. Laboratory demography studies of the freshwater cladoceran, Daphnia pulex, feeding on variously limited unialgal and multi- algal foods will be undertaken. These studies will ascertain the relationship between growth rate and quality in simple systems. In addition, food quality effects in natural populations will be examined through a set of experiments and measurements including 1. assessment of nature and degree of nutrient limitation in algal populations, 2. assessment of degree of food limitation in zooplankton populations, 3. measurement of assimilation efficiency of N and P in zooplankton. These data will then be used to explore in theoretical models how the stability and tendency for coexistence of herbivore and algae is influenced by food quality effects. Results will contribute to the conceptual basis of limnology and will add to the information base for managing aquatic resources.