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Macrobenthic bioturbation affects the environment, and variances in habitat, such as decreased dissolved oxygen concentration and increased ammonia concentration, affects the macrobenthic community. The relationship between macrobenthos and habitat factors may be a mutually causal relationship. The bottom-sowing culture for Manila clam Ruditapes philippinarum in many coastal countries plays an important role in coastal fisheries, and the relationship between Manila clam and other macrobenthos affects the ecological stability of the bottom-sowing culture zone. It is necessary to explore the relationship between them to manage the waters used for the bottom-sowing culture for Manila clam. In this study , from June to October 2021, the field investigation on macrobenthos including Manila clam and their habitat factors, such as particle size, nutrient content, redox potential, and organic matter content, in 21 experimental communities enclosed by bolting-silk net in Shuangdao Bay, Weihai, Shandong, China was conducted, during which macrobenthos functional groups were determined by feed sources and motor behavior. The results showed that Manila clam biomass was 7.215±0.984 g/m2 (calculated by dry soft tissue weight), and it was positively correlated with the biomass of macrobebthos functional groups B1, G1 and P1; water content in sediment; sulfide content in interstitial water; the Shanon-Wiener diversity index; Pielou’s evenness index and the W statistic of the ABC (Abundance-Biomass Comparison) curve (p< 0.05). Moreover, it was negatively correlated with sediment particulate size and HCl-NO3 content in sediment (p< 0.05). The action of Manila clam to habitats was the dominant role of the interaction between clam and habitat. Thus, the bottom-sowing culture for Manila clam does not decrease the macrobenthic community stability, and the invasion of other macrobenthos into the bottom-sowing culture zones for Manila clam may be accidental or inevitable. The results of our study suggest that the management of the bottom-sowing culture for Manila clam should be conducted from ecosystem level; i.e., fishing and aquaculture in the same waters are regarded as two components of an ecosystem; manage them together, rather than treat them separately.

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This paper presents the hierarchical linkage scheduling emergency supplies problem. A mathematical description is provided and a model of the hierarchical scheduling emergency supplies with multiple supplies and multiple vehicles is formed in order to acquire the shortest scheduling time and the lowest cost. For this problem, we give a two-stage scheduling case of supplies in this paper. This case consists of a primary transportation system including primary storage, secondary storage and primary road network(normal road and highway), and the secondary system which includes secondary storage, disaster point and secondary road network(normal road). In order to facilitate the expression, we named primary first-stage and secondary second-stage. After that, we define the hybrid of shortest scheduling time and cost as the objective function in this two-stage system. An improved genetic algorithm is applied to calculate this case. Thus, we can obtain the scheduling plan after implementing a global linkage approach.