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Li X.,Chinese Academy of Fishery Sciences | Yu Z.,Fresh Water Fishery Research Institute of Shandong Province | Sun S.,Chinese Academy of Fishery Sciences | Jin X.,Chinese Academy of Fishery Sciences
Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban | Year: 2013

Based on the fishery resources data from the bottom trawl surveys conducted on the R/V Beidou in the Yangtze River estuary and its adjacent waters in June, August and October of 2006, the index of relative importance (IRI) was measured to determine the dominant species of fish assemblage, and the niche indicators and their seasonal variations of the dominant species were analyzed. A total of 10 dominant species in the 3 survey cruises were recorded, which were divided into two groups by the Bray-curtis similarity clustering and non-metric multidimensional scaling (MDS) analysis, with a significant seasonal variation of niche breadth and niche overlap. One group included Engraulis japonicus, Champsodon capensis, and Acropoma japonicum, whose niche breadth and niche overlap were larger in summer than in autumn, with a migration from the Yangtze River estuary and its adjacent waters to outer deeper waters, while the other group included Trichiurus haumela, Chaeturichthys stigmatias, Apogon lineatus, Larimichthys polyactis, Psenopsis anomala, Argyrosomus argentatus, and Benthosema pterotum, whose niche breadth and niche overlap were larger in autumn than in summer, with a reverse migration from southern Yellow Sea and northern East China Sea to the Yangtze River estuary and its adjacent waters. The different migration direction of the two groups was related to their ecological habits and environmental factors. Source

Dong G.,Ocean University of China | Dong G.,Fresh Water Fishery Research Institute of Shandong Province | Dong S.,Ocean University of China | Wang F.,Ocean University of China | Tian X.,Ocean University of China
Aquaculture Research | Year: 2010

Eight light-intensity treatments (natural light, continuous darkness, and 15, 30, 60,125, 250 and 500 lx under LD12:12 cycle) were used to investigate the effects of light intensity on the daily activity of 30.27 ± 3.08 g sea cucumber Apostichopus japonicus (Selenka). Cyclic nocturnal activity patterns of behaviour were observed at different light intensities in the range of 15-500 lx under LD 12:12 cycle. And an ongoing nocturnal cycle persisted in DD cycle for up to 8 days, but longer feeding time and less marked rhythm occurred at continuous darkness. Under poor light conditions (I<5.18 lx), the daily activity rhythm of A. japonicus was governed by an innate biological clock and the effect of light intensity was not significant among different treatments. Andmore individuals tended to retreat to shelters (from 56.04% to 91.83%) with the increase of light intensity within the weak light condition (from 5.18 to 278 lx). However, the daily behaviours of A. japonicus were in£uenced under strong light conditions (>278 lx). Less than 8.17% individuals kept actively feeding and the proportion was not decreased with the increase of light intensity. © 2010 Blackwell Publishing Ltd. Source

Dong G.,Ocean University of China | Dong G.,Fresh Water Fishery Research Institute of Shandong Province | Dong S.,Ocean University of China | Wang F.,Ocean University of China | Tian X.,Ocean University of China
Aquacultural Engineering | Year: 2010

In the present studies, the effects of various artificial shelters on behavior of juvenile sea cucumber, Apostichopus japonicus, were evaluated. The preferences of animals in the experiments with eight different artificial material shelters were compared, and showed that shelters of stone, cement pipe, polywoven fabric (a synthetic woven material mainly composed of polypropylene), ceramic tile and PVC (polyvinylchloride) pipe attracted significantly more animals than low-pressure polyethylene pipe, wood block and corrugated PVC board (P< 0.05). The influences of shelters pre-incubation for 0.5. M (month), 1. M, 1.5. M and 2. M to grow biofilm on the shelter selection of the animals were compared with non-incubation shelters (0. M), and showed that the numbers of the animals attracted by incubated shelters were significantly greater than that without incubation, and the 1.5. M shelters attracted significantly more sea cucumbers than other treatments (P< 0.05) except 2. M (P> 0.05). Among six color shelters white shelter attracted less juvenile A. japonicus than green, red and blue ones, and there were no significant differences among white, yellow and black shelters (P> 0.05). © 2010 Elsevier B.V. Source

Yan F.-J.,Ocean University of China | Yan F.-J.,Fresh Water Fishery Research Institute of Shandong Province | Tian X.-L.,Ocean University of China | Dong S.-L.,Ocean University of China | Yang G.,Ocean University of China
Chinese Journal of Applied Ecology | Year: 2014

The functional diversity of aquatic microbial communities in sea cucumber (Apostichopus japonicus) cultural ponds was examined in this paper. The Biolog plate technique and redundancy analysis (RDA) method were used to evaluate seasonal changes and their relationships with environmental factors. The results showed that both total amount and types of carbon sources utilized by microbes in the sea cucumber cultural ponds varied seasonally, and were the highest in summer and lowest in winter, with polymers being the main type of carbon sources. Principal component analysis revealed that the carbon utilization diversity of the microbial communities varied significantly over the seasonal courses. A total of 10 categories of carbon sources were significantly related to the principal component 1, among which were polymers, carbohydrates, carboxylic acids, amino acids, and amines. Significant seasonal changes were detected for all carbon utilization diversity indices of the microbial communities, including Shannon, McIntosh, Simpson, and S-E. However, seasonal variations were different among the microbial diversity indices. RDA analysis revealed that TP, NO3 --N, TN, and PO4 3--P were the critical environmental factors influencing the seasonal changes in functional diversity of aquatic microbial community in sea cucumber cultural ponds. Source

Jiang R.,Shandong University | Li X.,Fresh Water Fishery Research Institute of Shandong Province | Zhu Y.,Fresh Water Fishery Research Institute of Shandong Province | Zhang Z.,Shandong University
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2011

Study of vegetation productivity and carbon sequestration of wetland ecosystem is a main research topic of global carbon cycle and global change. The ecosystem productivity study of Yellow River Delta, a wetland delta with fastest reclamation speed in China and in the world, is therefore extremely important. Due to human activities have affected all of ecological systems, to find an expeditious way to assess the ecosystem health becomes the major topic of current study. Net primary productivity (NPP) is a key component of terrestrial carbon cycle, and it is defined as the accumulative organic matters by green plants per unit of time and space. NPP, the direct reflection of plant community productivity for a certain natural environment, is the basis of matter and energy cycles of terrestrial ecosystem. The Normalized Difference Vegetation Index has been used for many years to measure and monitor plant growth, vegetation cover, and biomass production from multispectral satellite data. It is an indicator of vegetation growth and its spatial distribution has a close relationship with climate conditions. We use MODIS NPP and NDVI data to analyze the characteristics of spatial-temporal variation of NPP and NDVI in Yellow River Delta between 2001 and 2006. Distribution of NDVI shows that soil water-salt distribution is the main controlling factor of plant growth in the delta. The distribution of primary productivity has been obviously affected by human activities. We further built a new coastal regression model. As the changeable different regions which have different distances from the coastline and which have different lengths, we discuss the correlation between annual NPP (aNPP) and average annual NDVI (ANDVI). Results suggest that distribution of wetland ecosystems in the Yellow River Delta has obvious spatial heterogeneity from sea to land, along with the ecosystem succession. Mud flat along the coastline is a place for developing ecosystem with a large amount of pioneer plants, which has high productivity and their aNPP is positively related to ANDVI. Saline-alkali land has a low lever of aNPP because of higher concentration of salts; Agricultural land is a developed mature ecosystem in which the nutrition circulates only inside the ecosystem and affected mostly by human activities. Thus there is no directly relationship between aNPP and ANDVI in saline-alkali land and agriculture land, Consequently, we preliminarily discussed the feasible regions in the Yellow River Delta that can use MODIS NDVI to monitor their productivity. In the region where the distance to coastline is less than 6km, all of six simple regression models for each year passed the significant F-test (α=0.01, R2 0.86 - 0.97). Finally, to understand the time differentiation characteristics of correlation coefficient between ANDVI and aNPP, we calculated the percentage size and the average aNPP with different ANDVI value range. We figured out that resource competition may be one of the fact making the correlation coefficient difference. Therefore, we can use NDVI to effectively monitor and manage the ecosystems and to increase their productivity. Based on the research of the ecosystem productivity of Yellow River Delta, we can effectively understand the regularity for change of productivity during the rapid economic development period, which can further guide the administration of local ecosystems. Source

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