Nearshore Key Food Web Ecological Restoration Technique Of Bohai Bay

An ecological restoration technique based on the construction of local key foodweb was proposed to restore the degraded nearshore marine ecosystem of Bohai Bay.The Harbor1of Tianjin Lin Gang Economic Zone was taken as a hypotheticalrestoration exercise to elucidate the proposed technique. In the proposed restorationtechnique, the local pioneer species were screened and the local key food web wasbuilt according to the trophic relationships of screening species. The trophicrelationships of food web were quantified to determine the biomass ratio between thescreening species of each trophic level and finally the value of biomass of restorationinput was fixed based on the local primary prouction. The target ecosystem wasformed by the key food web with quantitative trophic relationship.The target ecosystem and the existing ecosystem (the ecosystem before restoration)were evaluated by using Ecopath model and the ocean health index to predict theexpected restoration effect. The results showed that the target ecosystem is moremature and healthy than the existing ecosystem. The ocean health index of the targetecosystem is86.3, which is much higher than that (51.8) of the existing ecosystem.The strengthening ecological restoration methods, such as artificial reef, hardsurface roughening and artificial reef with hard surface roughening simultaneously,were taken to improve the restoration effect of example area. The expectedstrengthening effect was predicted from the aspects of maturity and health ofecosystem by using Ecopath model and the ocean health index. The results indicatedthat above three strengthening methods are all effective and the strengthening effectof artificial reef with hard surface roughening simultaneously is the best.It was concluded that the key food web ecological restoration technique is effectiveand the strengthening ecological restoration methods improves the restoration effectof the proposed technique. The model of the proposed technique should be initiatedand applied in the other restoration of nearshore marine ecosystem.