Study On Development Mode Of Shenyang Hunhe Ecological Fishery

In our country,the aquatic resources are rich and the fisheries development foundation is very good.The robust development of fishery economy are important for the adjustment of agricultural structure,the increase of farmers' income and the improvement of people's dietary structure.But with the change of the social and economic development,fish resources are going through a serious recession.As a result,scientific development of the fishery resources is a serious subject for us.Fishery resources is the material basis of fishery production and the realization of the sustainable utilization of fishery resources is a prerequisite for the sustainable development of fishery.According to the actual situation,choosing an efficient mode of fishery development,making full use of water energy and biological resources are of great importance.Hunhe,called Hunshui in ancient time,is the natural waterways of Shenyang.The length of it is 415 km,which flows through the middle east of Liaoning Province,and finally flows into the Bohai sea.Hunhe has abundant fishery resources in the past.But in recent years,it faces river pollution,fishery resources recession and so on.In order to set up an ecological mode of fishy development,the urgent work includes doing a full investigation on the fishery resources and ecological environment in Hunhe and making a reasonable strategy of fishy development.The main contents and contributions are as follows:The first part reviews the current situation and the existing problems of fisheries development.The main problems include superfluous water diversion quantity,over fishing,alien species invasion,water pollution and other issues.The second part analyzes the current situation of Hunhe,including the geography,topography,landform,the climate characteristics,hydrological system and so on.This chapter focuses on the effects of agricultural pollution,water shortages,overfishing,insufficient attention on fishery development.The third part studies the present situation,the composition of aquatic organisms,the breeding habits and the fisheries production of Hunhe by reading literature,social investigation,etc.The body weight and length of the main economic fish species(including rhodeus ocellatus,crucian carp,bighead carp)are analyzed.Firstly,FISAT_II software is used to solve the relation between body weight and body length,to estimate the critical age of weight growth.The quantity of resource of main economic fish species is obtained.Secondly,the Ecopath software is used to build an Ecopath model of ecological system,which covers 22 functional groups including silver carps,oxtail,carp,carp,black carp,grass carp and so on.Lastly,combing the food web structure and the direction of energy flow,the ecological capacities of typical species such as silver carps,oxtail,carp,carp,black carp and grass carp are given.The last part studies the development mode of ecological fishery.According to the tendency of the fisheries development,a series of reasonable strategies is presented,such as relaxation fishery,technology fishery and facility fishery.Besides,some suggestions from the aspects of technology,ecology and talent are also proposed.