The Limits to Copepod Growth: Resolving the Malthusian Dilemma

桡足类生长的限制：解决马尔萨斯困境

• 批准号: 9201476
• 负责人: Mark Huntley
• 金额: $ 20.07万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-07-15 至 1995-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9201476&HistoricalAwards=false
• 关键词: Limits; Copepod; Growth; Resolving; Malthusian

Zooplankton are the major pathway for carbon transfer to higher trophic levels, and to deeper water and the sediments. Estimates of zooplankton production are critical in understanding how short and long term variations in primary production affect these rates of carbon transfer. Drs. Huntley and Lopez have hypothesized that copepod growth is predictable with first-order precision from habitat temperature alone. If this relationship proves to be robust, we will have a powerful tool for estimating zooplankton production. However, the apparent simplicity of this relation raises major issues about plankton dynamics since it denies the usual assumption that zooplankton are food-limited. These investigators from the Universities of California and Hawaii will investigate the thesis that, at the population level, food limitation of copepods operates mainly through changes in mortality rate. They suggest that there is strong evidence for this in fish populations where density dependence operates on the mortality of the early life stages. Thus, the general solution of the Malthusian dilemma for marine populations is to die young rather than starve later. They will address these key questions in the following ways: - (1) Direct measurements of the generation times of a variety of warm-water copepod species, to fill a critical gap in the database; - (2) Experimental testing of the hypothesis that size-specific predation pressure can compensate for the effects of food-limited growth rate by increasing apparent development rate at the population level.

浮游动物是碳转移到 更高的营养水平，更深的水和沉积物。 对浮游动物产量的估计对于理解 初级生产的短期和长期变化如何影响 这些碳转移的速率。 亨特利和洛佩斯医生 假设桡足类的增长是可预测的一阶 仅来自栖息地温度的精确度。 如果这种关系 被证明是稳健的，我们将有一个强大的工具来估计 浮游动物生产 然而，这一点的明显简单性 关系提出了关于浮游生物动态的重大问题，因为它 否定了浮游动物食物有限的通常假设。 这些来自加州大学的研究人员和 夏威夷将研究的论点，在人口水平上， 桡足类的食物限制主要通过改变 死亡率 他们认为，有强有力的证据表明， 这在鱼类种群中，密度依赖于 生命早期阶段的死亡率。 因此， 海洋种群面临的马尔萨斯困境是夭折 而不是以后挨饿 他们将解决这些关键问题， 以下方式： - (1)直接测量一个变种的世代时间 暖水桡足类物种，以填补一个关键的空白， 数据库; - (2)实验测试的假设，大小特异性 捕食压力可以补偿食物限制的影响 增长率通过提高表观发展率 人口水平。