基于初级生产力的海洋生物资源承载力评估——以日照近岸海域为例

The assessment of carrying capacity of marine biology resources based on primary productivity method——A case study of coastal waters of Rizhao

资源环境承载力研究亟待突破承载阈值界定与关键参数率定的技术瓶颈,并建立一套标准化的定量评价关键技术。本研究基于“资源量?消费量”模型,通过调查与实验分析获取特定海区的初级生产力、浮游植物有机碳含量、鱼类营养级等关键参数值,采用营养动态模型和Tait沿岸海域能流模型来估算海洋生物资源总量,然后根据年人均水产品摄入量或年人均蛋白质摄入量来计算该海区海洋生物资源承载力的阈值。根据2016年对日照辖区海域的生态环境状况调查,该海域年平均初级生产力(以C计)为428.22 mg/(m^2·d),浮游植物年生产量为918.51万t,鱼类、虾蟹类和头足类的平均营养级分别为3.85、3.92和3.90,利用营养动态模型计算海域渔业资源(鱼类、虾蟹类和头足类)的年生产量为3.89万t;根据Tait沿岸海域能流模型计算日照10 m等深线以内浅海的除去壳重的贝类资源量为5.50万t。按照年人均水产品摄入量为21 kg,计算出日照辖区海域的海洋生物资源承载力总和为192.86万人;按照年人均摄入蛋白质量为30 kg,计算出日照辖区海域的海洋生物资源承载力总和为16.87万人。本文建立了一项具有广泛适用性的海洋生物资源承载力定量评价技术,对科学地开发利用海洋生物资源和建立陆海统筹的资源环境承载力的监测预警机制起到积极的促进作用。

The technical bottlenecks of threshold determination and key parameter calibration in carrying capacity of resources and environment urgently need to be broken through,and then establish a standardized quantitative evaluation method.In the present study,several key parameters such as primary productivity,phytoplankton organic carbon content and trophic level were obtained through investigation and experimental analysis.The nutrition dynamic model and the Tait coastal energy flow model were used to estimate the total quantities of marine biological resources.Then,the threshold of carrying capacity of marine biological resources was calculated based on the“resource-consumption”model.For example,according to the survey results in 2016,the annual average primary productivity of sea area under Rizhao jurisdiction was 428.22 mg/(m2·d)and the annual production of phytoplankton was 9.19×10^6 t.Meanwhile,the average trophic levels of fishes,shrimps and crabs,and cephalopods were 3.85,3.92 and 3.90,respectively.The annual production of fishery resources(fish,shrimp and crab,and cephalopod)in the sea area was 38.9 thousand tons calculated by the“nutritional dynamic model”.In addition,the shellfish resources in shallow sea within 10 m depth contour was 55 thousand tons calculated by the Tait coastal energy flow model.Thus,according to the annual per capita intake of aquatic products of 21 kg,the total carrying capacity of marine biological resources in Rizhao coastal waters was 1.9286×10^6 people.Meanwhile,according to the annual per capita protein intake of 30 kg,the total carrying capacity of marine biological resources in Rizhao area was calculated to be 1.687×10^5 people.Taken together,this paper describes a quantitative assessment technique with wide applicability for carrying capacity of marine biological resources.This will contribute to substantial utilization of the marine biological resources and establishment of the monitoring and early warning of resources and environment carrying capacity in a way of overall planning of land and sea.