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trophic Interaction in a Portunus rituberculatus Polyculture Ecosystem Based on Carbon and Nitrogen Stable Isotope Analysis

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Journal of Ocean University of China 2018年第6期17卷 1432-1440页

作者： FENG Jie TIAN Xiangli DONG Shuanglin LI Da HE Ruipeng ZHANG Kai ZHANG Dongxu ZHANG Qingqi The Key Laboratory of Mariculture of Ministry of Education Fisheries CollegeOcean University of ChinaQingdao 266003China Marine Fishery Technology Guiding Office of Ganyu Lianyungang 222100China Marine and Fisheries Research Institute of Rizhao Rizhao 276800China

trophic interaction among various biomass groups in a swimming crab Portunus trituberculatus polyculture pond was investigated using carbon and nitrogen stable isotope analysis. The polycultured animal species also included white shrimp Litopenaeus vannamei, short-necked clam Ruditapes philippinarum, and redlip mullet Liza haematochila. The mean δ^(13)C value for all the biomass groups in polyculture ecosystem ranged from -25.61‰ to -16.60‰, and the mean δ^(15)N value ranged from 6.80‰ to 13.09‰. Significant difference in the δ^(13)C value was found between particulate organic matter(POM) and sediment organic matter(SOM)(P < 0.05), indicating that these two organic matter pools have different material sources. Assuming that a ^(13)C-enrichment factor of 1.00‰ and a ^(15)N-enrichment factor of 2.70‰ existed between consumer and prey, diets of the four cultured animals were estimated using a stable isotope mixing model. The estimated model results indicated that P. trituberculatus mainly feed on Aloidis laevis; L. vannamei mainly feed on shrimp feed; while A. laevis, R. philippinarum and L. haematochelia mainly feed on POM. Shrimp feed was also an important food source of R. philippinarum and L. haematochelia. The diets of P. trituberculatus, L. vannamei, R. philippinarum, and L. haematochila showed complementary effects in this polyculture ecosystem. Our finding indicated that the polyculture of these four organisms with suitable farming density could make an effective use of most of the food sources, which can make a highly efficient polyculture ecosystem.

关键词： trophic interaction Portunus trituberculatus polyculture stable isotope diet composition

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trophic factors are essential for the survival of grafted oligodendrocyte progenitors and for neuroprotection after perinatal excitotoxicity

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Neural Regeneration Research 2020年第3期15卷 557-568页

作者： Megumi Hirose-Ikeda Brian Chu Paul Zhao Omar Akil Elida Escalante Laurent Vergnes Carlos Cepeda Araceli Espinosa-Jeffrey Intellectual and Developmental Disabilities Research Center Jane and Terry Semel Institute for Neuroscience and Human BehaviorDepartments of NeurobiologyPsychiatry&Biobehavioral SciencesUniversity of CaliforniaLos AngelesCAUSA Department of Human Genetics David Geffen School of MedicineUniversity of CaliforniaLos AngelesCAUSA

The consequences of neonatal white matter injury are devastating and represent a major societal problem as currently there is no ***,low weight birth and maternal pre-natal infection are the most frequent causes of acquired myelin deficiency in the human neonate leading to cerebral palsy and cognitive *** the developing brain,oligodendrocyte(OL)maturation occurs perinatally,and immature OLs are particularly *** replacement therapy is often considered a viable option to replace progenitors that die due to glutamate *** previously reported directed specification and mobilization of endogenous committed and uncommitted neural progenitors by the combination of transferrin and insulin growth factor 1(TSC1).Here,considering cell replacement and integration as therapeutic goals,we examined if OL progenitors(OLPs)grafted into the brain parenchyma of mice that were subjected to an excitotoxic insult could rescue white matter *** that purpose,we used a well-established model of glutamate excitotoxic ***-day-old mice received a single intraparenchymal injection of the glutamate receptor agonist N-methyl-D-aspartate alone or in conjunction with TSC1 in the presence or absence of OLPs grafted into the brain *** and expression of stress proteins and OL developmental specific markers were examined.A comparison of the proteomic profile per treatment was also *** found that OLPs did not survive in the excitotoxic environment when grafted *** contrast,when combined with TSC1,survival and integration of grafted OLPs was ***,energy metabolism in OLPs was significantly increased by N-methyl-D-aspartate and modulated by *** proteomic profile after the various treatments showed elevated ubiquitination and stress/heat shock protein 90 in response to *** changes were reversed in the presence of TSC1 and ubiquitination was *** results obtained i

关键词： myelin regeneration myelination oligodendrocytes periventricular leukomalacia premature birth proteomics trophic factors white matter injury

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Historical trophic evolutions and their ecological responses from shallow lakes in the middle and lower reaches of the Yangtze River: Case studies on Longgan Lake and Taibai Lake

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Science China Earth Sciences 2006年第z1期49卷 51-61页

作者： YANG Xiangdong SHEN Ji DONG Xuhui LIU Enfeng WANG Sumin Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China

The evolutions of diatom floras and the total phosphorous (TP) concentrations in the historical period were reconstructed for two lakes, Longgan and Taibai in the middle Yangtze River,based on high resolutional fossil diatom study from two sediment cores and an established regional diatom-TP transfer function. The TP concentration in Longgan Lake changed slightly in the range of 36-62 μg/L and kept its middle trophic level in the past 200 years. The changes of diatom assemblages reflect a macrophyte-dominated history of the lake. During the nineteenth century, the lake TP concentration increased comparatively, corresponding to the increase in abundance of benthic diatoms. The progressive increase of epiphytic diatoms since the onset of the twentieth century indicates the development of aquatic plants, coinciding with the twice drops of water TP level. The TP concentration in Taibai Lake kept a stable status about 50 μg/L before 1953 AD, while diatoms dominated by facultative planktonic Aulacoseira granulata shifted quickly to epiphytic diatom species, indicating a rapid expansion of aquatic vegetation. During 1953-1970 AD, the coverage of aquatic plants decreased greatly inferred by the low abundance of epiphytic diatoms as well as declined planktonic types, and the reconstructed TP concentration shows an obvious rising trend firstly, suggesting the beginning of the lake eutrophication. The lake was in the eutrophic condition after 1970, coinciding with the successive increase of planktonic diatoms. The comparison of the two lakes suggests the internal adjustment and purification function of aquatic plants for nutrients in water. The discrepancy of TP trends in the two lakes after 1960 reflects two different patterns of lake environmental response to human disturbance. Sediments in Taibai Lake clearly recorded the process of lake ecological transformation from the macrophyte-dominated stage to the algae-dominated stage. The limits of TP concentration (68-118 μg/L) i

关键词： diatom, quantitative reconstruction of total phosphorous, trophic evolution, lake ecology, the middle and lower reaches of Yangtze River.

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Establishment of trophic continuum in the food web of the Yellow Sea and East China Sea ecosystem: Insight from carbon and nitrogen stable isotopes

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Science China(Life Sciences) 2005年第6期48卷 531-539页

作者： CAI Deling1, LI Hongyan2, TANG Qisheng3 & SUN Yao3 1. Key Laboratory of Marine Sedimentology & Environment Geology, SOA, First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China 2. Ocean University of China, Qingdao 266003, China 3. Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China 1. Key Laboratory of Marine Sedimentology & Environment Geology SOA First Institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. Ocean University of China 266003 Qingdao China 3. Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences 266071 Qingdao China

Stable carbon and nitrogen isotope ratios (δ13C and δ15N) are used to study the trophic structure of food web in the Yellow Sea and East China Sea ecosystem. The trophic con-tinuum of pelagic food web from phytoplankton to top preyer was elementarily established, and a trophic structure diagram in the Yellow Sea and East China Sea was outlined in combination with carbon isotopic data of benthic organisms, which is basically consistent with and makes some improvements on the simplified Yellow Sea food web and the trophic structure diagram drawn based on the biomass of main resource population during 1985―1986. This result indicates that the stable isotope method is a potential useful means for further studying the complete marine food web trophic continuum from viruses to top predators and food web stability.

关键词： food web, trophic continuum, carbon isotope, nitrogen isotope, Yellow Sea, East China Sea.

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Trace metals in barnacles:the significance of trophic transfer

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Science China(Life Sciences) 2005年第z1期48卷 110-117页

作者： Philip S. RAINBOW Department of Zoology the Natural History Museum Cromwell Road London SW7 5BD London UK

Barnacles have very high accumulated trace metal body concentrations that vary with local trace metal bioavailabilities and represent integrated measures of the supply of bioavailable metals. Pioneering work in Chinese waters in Hong Kong highlighted the potential value of barnacles (particularly Balanus amphitrite) as trace metal biomonitors in coastal waters,identifying differences in local trace metal bioavailabilities over space and time. Work in Hong Kong has also shown that although barnacles have very high rates of trace metal uptake from solution, they also have very high trace metal assimilation efficiencies from the diet. High assimilation efficiencies coupled with high ingestion rates ensure that trophic uptake is by far the dominant trace metal uptake route in barnacles, as verified for cadmium and zinc. Kinetic modelling has shown that low efflux rate constants and high uptake rates from the diet combine to bring about accumulated trace metal concentrations in barnacles that are amongst the highest known in marine invertebrates.

关键词： barnacles, trophic transfer, assimilation efficiency, trace metals.

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trophic Status of Shallow Lakes of La Pampa (Argentina) and Its Relation with the Land Use in the Basin and Nutrient Internal Load

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Journal of Environmental Protection 2013年第11期4卷 51-60页

作者： Santiago A. Echaniz Alicia M. Vignatti Departamento de Ciencias Biológicas Facultad de Ciencias Exactas y Naturales Universidad Nacional de La Pampa Santa Rosa Argentina.

Phosphorus and nitrogen are essential nutrients for living organisms. Their concentration in the water of an aquatic ecosystem is one of the factors responsible for the trophic status of the lake and is related to the soils of the region and to the human activities carried out in their basins. These nutrients are also found in the bottom sediments, where they can either be retained or re-enter the water column. Since the information about the concentrations of nutrients in the water of some lakes of La Pampa (Argentina) is fragmentary, the aim of this study is to describe the trophic status of some shallow lakes of the semiarid center of Argentina and analyze its relation with the human activities in their basins, the concentrations of nutrients and organic matter and particle size distribution of sediments. To this end, we studied ten shallow lakes subjected to different anthropogenic influences (agriculture, agriculture and livestock and impacted by cities). All were hypertrophic and the concentrations of total phosphorus and total nitrogen were among the highest reported globally. Since some lakes had no fish, cladoceran grazing (top-down effect) led them have reduced concentrations of phytoplankton chlorophyll-a and high water transparency. This relativizes the use of these parameters to determine the trophic status. The sediments of seven of the studied lakes were predominated by fine sands, whereas three were predominated by silts. Nutrient and organic matter content were high, with higher concentrations in lakes with prevalence of fine particles. The reduced adsorption capacity of sediments, the resuspension by wind, the anthropogenic input and the accumulation favored by the arheic character of the basins would explain the high concentrations of nutrients in the water of these Pampean environments.

关键词： Eutrophication trophic State Total Phosphorus Shallow Lakes Internal Load Land Use

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Amniotic fluid： Source of trophic factors for the developingintestine

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World Journal of Gastrointestinal Pathophysiology 2016年第1期7卷 38-47页

作者： Soham Dasgupta Shreyas Arya Sanjeev Choudhary Sunil K Jain Department of Pediatrics University of Texas Medical BranchGalvestonTX 77555United States2Department of EndocrinologyUniversity of Texas Medical BranchGalvestonTX 77555United States Department of Internal Medicine University of Texas Medical BranchGalvestonTX 77555United States Department of Neonatology University of Texas Medical BranchGalvestonTX 77555United States

The gastrointestinal tract(GIT) is a complex system, which changes in response to requirements of the body. GIT represents a barrier to the external environment. To achieve this, epithelial cells must renew rapidly. This renewal of epithelial cells starts in the fetal life under the influence of many GIT peptides by swallowing amniotic fluid(AF). Development and maturation of GIT is a very complex cascade that begins long before birth and continues during infancy and childhood by breastfeeding. Many factors like genetic preprogramming, local and systemic endocrine secretions and many trophic factors(TF) from swallowed AF contribute and modulate the development and growth of the GIT. GIT morphogenesis, differentiation and functional development depend on the activity of various TF in the AF. This manuscript will review the role of AF borne TF in the development of GIT.

关键词： Amniotic Fluid Gastrointestinal Factors Tract trophic Development

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Plankton- Based Assessment of the trophic State of Three Tropical Lakes

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Journal of Environmental Protection 2011年第3期2卷 304-315页

作者： Benedict Obeten Offem Ezekiel Olatunji Ayotunde Gabriel Ujong Ikpi F. B. Ada S. N. Ochang 不详

In developing countries, lakes being important sources of water supply and fishing are vulnerable to anthropogenic impact, yet knowledge of their trophic state in relation to changes in species composition, and environmental variables, are limited. This study is aimed at assessing the trophic status of lakes by monthly sampling of three lakes located along the floodplain of Cross River, Nigeria between January 2008 and December 2009. Samples were analyzed for water quality parameters, zooplankton and phytoplankton composition and distribution. Results were subjected to community structure analysis using trophic state index, species richness and diversity indexes. Essential primary productivity nutrients, nitrates, sulphates and phosphates were highest in Ejagham Lake, and lowest in Ikot Okpora Lake. Dominant phytoplankton species Oscillatoria lacustria (Cyanophyceae), Cyclotella operculata (Bacilliarophyceae) and zooplankton Keratella tropica, Keratella quadrata, Filinia longiseta, Branchionus anguillaris and Trichocerca pusilla (rotifers) all typical of eutrophic communities were recorded in high densities in Ejagham Lake in both dry and wet seasons while Cladocerans, Bosmina longirostris and Moina micrura and copepods considered indicators of oligotrophy and mesotrophy were recorded in large numbers in Ikot Okpora and Obubra Lakes respectively. Higher values of species richness, Evenness and Shannon-Wiener diversity index for both phytoplankton and zooplankton, were recorded in Ejagham Lake during the dry season than wet. Also values of the trophic state index were generally highest at the Ejagham Lake in the savanna region of the floodplain and lowest at Ikot Okpora in the forest region of the floodplain. Forest region is therefore a limiting factor in the productivity of lakes in the tropics.

关键词： Zooplankton Phytoplankton trophic State Index Diversity Indices Species Richness

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Water Quality Assessment, trophic Classification and Water Resources Management

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Journal of Water Resource and Protection 2010年第10期2卷 907-915页

作者： Arkadi Parparov Israel Oceanographic and Limnological Research Kinneret Limnological Laboratory Migdal Israel

Quantification of water quality (WQ) is an integral part of scientifically based water resources management. The main objective of this study was comparative analysis of two approaches applied for quantitative assessment of WQ: the trophic level index (TLI) and the Delphi method (DM). We analyzed the following features of these conceptually different approaches: A. similarity of estimates of lake WQ;B. sensitivity to indicating disturbances in the aquatic ecosystem structure and functioning;C. capacity to reflect the impact of major management measures on the quality of water resources. We compared the DM and TLI based on results from a series of lakes covering varying productivity levels, mixing regimes and climatic zones. We assumed that the conservation of aquatic ecosystem in some predefined, “reference”, state is a major objective of sustainable water resources management in the study lakes. The comparison between the two approaches was quantified as a relationship between the DM ranks and respective TLI values. We show that being a classification system, the TLI does not account for specific characteristics of aquatic ecosystems and the array of different potential uses of the water resource. It indirectly assumes that oligotrophication is identical to WQ improvement, and reduction of economic activity within the lake catchment area is the most effective way to improve WQ. WQ assessed with the TLI is more suitable for needs of natural water resources management if eutrophication is a major threat. The DM allows accounting for several water resource uses and therefore it may serve as a more robust and comprehensive tool for WQ quantification and thus for sustainable water resources management.

关键词： Water Quality trophic Level Index Delphi Method Sustainable Management Lakes

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Study on the Applicability of Landsat-8 Images as a Tool for Monitoring the trophic State of Lake Guiers (Senegal)

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Journal of Water Resource and Protection 2019年第4期11卷 434-447页

作者： Charles Diédhiou Seybatou Diop Gayane Faye Tijani Moshod Souléye Wade Institute of Earth Sciences Faculty of Sciences and Techniques Cheikh Anta Diop University Dakar Senegal Department of Geology University of Ibadan Ibadan Nigeria

In this study, an algorithm to transform LANDSAT 8 images of Lake Guiers into chlorophyll-a concentration maps was developed. The objective was to see the feasibility of this method as a mapping tool for monitoring the trophic state of the Lake. The available data are 15 in-situ measurements of the CHL-a content of Lake Guiers’ water using a Micro FLU device and images of the lake acquired in 2013 and 2016 by the LANSAT 8 OLI sensor. A series of correlation tests (simple linear functions, multi-variables, or containing two- order terms) were performed between the spectral sensor signal of June 19, 2016 LANSAT 8 image (“corrected” and converted into reflectance) and the CHL-a content of Lake waters measured on the same day of the satellite record. This was, to find the best regression equation that can be inferred to develop an algorithm to transform LANDSAT 8 image into CHL-a concentration maps. The best equation obtained by correlating the ground truths and the reflectance ratios of the visible and near infrared bands (B2, B3, B4 and B5), is as follows: where B2 = Blue band, B3 = Green band, B4 = Red band, B5 = NIR band. The obtained R2 is 0.703 (e.g., a correlation coefficientof 0.84), revealed that the measured concentrations are well reproduced by the regression model. Applying this model to the 2013 and 2016 image data revealed the monthly variations of the lake CHL-a contents and their seasonal evolution and interannual variations. The obtained results are quite consistent with those from similar studies and provide valuable information regarding Lake Guiers’ vulnerability to algal development. The calculation and analysis of the variability of the CHL-a contents over the study period made it possible to evaluate the trophic state of the Lake, which shows a general tendency for eutrophication process, leading to a progressive degradation of the quality of the water resource.

关键词： Lake Guiers LANDSAT 8 Chlorophyll a trophic State

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