A singular stochastic control model for sustainable population management of the fish-eating waterfowl Phalacrocorax carbo
A singular stochastic control model for sustainable population management of the fish-eating waterfowl Phalacrocorax carbo
复制标题
食鱼水禽 Phalacrocorax carbo 可持续种群管理的奇异随机控制模型
DOI：
10.1016/j.jenvman.2018.04.099
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发表时间：
2018
影响因子：
8.7
通讯作者：
Fujihara Masayuki
中科院分区：
文献类型：
--
作者：
Yaegashi Y;Yoshioka H;Unami K;Fujihara Masayuki
利用一个可处理的奇异随机控制模型，研究了日本江鱼的主要捕食者--食鱼水禽Phalacrocorax Caro(Great Cormorant)的可持续种群管理策略。栖息地湖泊周围的鸟类种群动态由一个带有奇异控制变量的随机微分方程来描述，该控制变量代表了人类干预以抑制捕食的行为。最优种群管理政策最大限度地提高了绩效指数，涵盖了应对措施的成本、沿江鱼类的损失以及鸟类提供的生态系统服务。动态规划原理得到了一个精确可解的变分不等式，它控制了一个可持续的临界型最优管理策略。在这项政策中，当人口达到一定水平时就采取对策。该模型被应用于管理OFP。日本琵琶湖周围的碳素种群，那里的河流鱼类被捕食是全国最严重的。在该模型的框架下，对现有的环湖管理政策进行了分析和验证，重点是人口控制阈值和单位时间内的平均人口减少。
Using a tractable singular stochastic control model, this study seeks a sustainable population management policy for the fish-eating waterfowlPhalacrocorax carbo(Great Cormorant), a major predator of riverine fish in Japan. The bird population dynamics around a habitat lake are described by a stochastic differential equation with a singular control variable representing human interventions to suppress the predation. The optimal population management policy maximizes a performance index that covers the cost of countermeasures, the loss of riverine fish, and the ecosystem services provided by the bird. The dynamic programming principle obtains an exactly-solvable variational inequality that governs a sustainable, threshold-type optimal management policy. In this policy, countermeasures are taken when the population reaches a certain level. The model is applied to management ofP. carbopopulation around Lake Biwa, Japan, where predation of riverine fish is the most severe in the country. The current management policy around the lake is analyzed and verified in the context of the proposed model, focusing on the population-control threshold and the average population reduction per unit time.