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A Quantitative Seismic Topographic Effect Prediction Method Based upon BP Neural Network Algorithm and FEM Simulation

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Journal of Earth Science 2024年第4期35卷 1355-1366页

作者： Qifeng Jiang Mianshui Rong Wei Wei Tingting Chen Shandong Seismic Hazard Prevention Center Shandong Earthquake AgencyJinan250014China Shandong Institute of Earthquake Engineering Jinan250021China Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University of TechnologyBeijing100124China Publicity and Education Center Shandong Earthquake AgencyJinan250014China Shandong Earthquake station Shandong Earthquake AgencyJinan250014China

Topography can strongly affect ground motion,and studies of the quantification of hill surfaces’topographic effect are relatively *** this paper,a new quantitative seismic topographic effect prediction method based upon the BP neural network algorithm and three-dimensional finite element method(FEM)was *** FEM simulation results were compared with seismic records and the results show that the PGA and response spectra have a tendency to increase with increasing elevation,but the correlation between PGA amplification factors and slope is not obvious for low *** BP neural network models were established for the prediction of amplification factors of PGA and response *** kinds of input variables’combinations which are convenient to achieve are proposed in this paper for the prediction of amplification factors of PGA and response spectra,*** absolute values of prediction errors can be mostly within 0.1 for PGA amplification factors,and they can be mostly within 0.2 for response spectra’s amplification *** input variables’combination can achieve better prediction performance while the other one has better expandability of the predictive ***,the BP models only employ one hidden layer with about a hundred nodes,which makes it efficient for training.

关键词： seismic topographic effect finite element method BP neural network algorithm earthquake disaster prevention

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Changes in the patterns of inorganic nitrogen and TN/TP ratio and the associated mechanism of biological regulation in the shallow lakes of the middle and lower reaches of the Yangtze River

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Science China Earth Sciences 2006年第z1期49卷 126-134页

作者： WU Shikai XIE Ping WANG Songbo ZHOU Qiong Donghu experimental station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

The changes of NH3-N, NO3-N, NO2-N and TN/TP were studied during growth and non-growth season in 33 subtropical shallow lakes in the middle and lower reaches of the Yangtze River. There were significant positive correlations among all nutrient concentrations, and the correlations were better in growth season than in non-growth season. When TP＞0.1 mgL-1, NH3-N increased sharply in non-growth season with increasing TP, and NO3-N increased in growth season but decreased in non-growth season with TP. These might be attributed to lower dissolved oxygen and low temperature in non-growth season of the hypereutrophic lakes, since nitrification is more sensitive to dissolved oxygen and temperature than antinitrification. When 0.1 mgL-1＞TP＞0.035 mgL-1, TN and all kinds of inorganic nitrogen were lower in growth season than in non-growth season, and phytoplankton might be the vital regulating factor. When TP＜0.035 mgL-1, inorganic nitrogen concentrations were relatively low and NH3-N, NO2-N had significant correlations with phytoplankton, indicating that NH3-N and NO2-N might be limiting factors to phytoplankton. In addition, TN/TP went down with decline in TP concentration, and TN and inorganic nitrogen concentrations were obviously lower in growth season than in non-growth season, suggesting that decreasing nitrogen (especially NH3-N and NO3-N) was an important reason for the decreasing TN/TP in growth season. The ranges of TN/TP were closely related to trophic level in both growth and non-growth seasons, and it is apparent that in the eutrophic and hypertrophic state the TN/TP ratio was obviously lower in growth season than in non-growth season. The changes of the TN/TP ratio were closely correlated with trophic levels, and both declines of TN in the water column and TP release from the sediment were important factors for the decline of the TN/TP ratio in growth season.

关键词： nitrate-nitrogen, ammonium-nitrogen, nitrite-nitrogen, shallow lakes, phytoplankton.

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experimental STUDIES ON THE ROLE OF PLANKTIVOROUS FISHES IN THE ELIMINATION OF MICROCYSTIS BLOOM FROM DONGHU LAKE USING ENCLOSURE METHOD

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Chinese Journal of Oceanology and Limnology 1996年第3期14卷 193-204页

作者：谢平 Donghu experimental station of Lake Ecosystems CERN Institute of Hydrobiology Chinese Academy of Sciences Wuhan

The hypertrophic subtropic Donghu Lake’s dense water bloom(of mainly Microcystis Anaabaena andOscillatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The infiuenceof planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years usingthe enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of waterbloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completelyeliminated in 10-20 days by introduction of silver and/or bighead carp(grass carp was not effectivein controlling water bloom).This study showed clearly that grazing pressure by planktivorous fishes is a keyfactor in eliminating water bloom from the lake.

关键词： enclosure experiments water bloom hypertrophic lake planktivorous fishes grazing pressure

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Expression levels of K_(ATP)channel subunits and morphological changes in the mouse liver after exposure to radiation

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World Journal of experimental Medicine 2024年第2期14卷 103-113页

作者： Ming Zhou Tao-Sheng Li Hiroshi Abe Hideo Akashi Ryoji Suzuki Yoshio Bando Department of Anatomy Akita University Graduate School of MedicineAkita 010-8543Japan Department of Stem Cell Biology Atomic Bomb Disease InstituteNagasaki UniversityNagasaki 852-8523Japan Sendai Old Age Refresh station A Long-term Care Health FacilitySendai 981-1105Japan

BACKGROUND ATP sensitive K+(K_(ATP))channels are ubiquitously distributed in various of cells and tissues,including the *** play a role in the pathogenesis of myocardial and liver *** To evaluate the radiation-induced changes in the expression of K_(ATP)channel subunits in the mouse liver to understand the potential role of K_(ATP)channels in radiation *** Adult C57BL/6 mice were randomly exposed toγ-rays at 0 Gy(control,n=2),0.2 Gy(n=6),1 Gy(n=6),or 5 Gy(n=6).The livers were removed 3 and 24 h after radiation *** and eosin staining was used for morphological observation;immunohistochemical staining was applied to determine the expression of K_(ATP)channel subunits in the liver *** Compared with the control group,the livers exposed to 0.2 Gyγ-ray showed an initial increase in the expression of Kir6.1 at 3 h,followed by recovery at 24 h after *** to a high dose of 5.0 Gy resulted in decreased expression of Kir6.1 and increased expression of SUR2B at 24 ***,the expression of Kir6.2,SUR1,or SUR2A had no remarkable changes at 3 and 24 h after exposure to any of these *** The expression levels of Kir6.1 and SUR2B in mouse liver changed differently in response to different radiation doses,suggesting a potential role for them in radiation-induced liver injury.

关键词： Radiation exposure ATP-sensitive K^(+)channel Mouse Liver

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Research and Application of Compressed Fermented Chestnut Leaf Feed in Fattening Mutton Sheep

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Agricultural Biotechnology 2024年第4期13卷 28-30,37页

作者： Lei WANG Xiaoyan LI Rundong QIANG Yu ZHOU Huihui CAO Shengyu SU Kaixuan ZHANG Changli WANG Hengzhi REN Daxin CHAI Yuli WANG Zhongkuan LIU Tangshan Food and Drug Comprehensive Inspection and Testing Center Tangshan 063000China Agriculture and Rural Affairs Bureau of Qianxi County Tangshan 063000China Tangshan Academy of Agricultural Sciences Tangshan 063000China Jidong Comprehensive experimental Promotion station of Grass Industry Innovation Team of Hebei Provincial Modern Agricultural Industry System Tangshan 063000China Yanshan University Qinhuangdao 066000China Institute of Agricultural Resources and Environment Hebei Academy of Agriculture and Forestry SciencesShijiazhuang 050050China

Chestnut leaves and bran were evenly mixed according to different mass ratios,and the mixtures were sprayed and inoculated with a certain amount of prepared EM microbial liquid,and then compressed into 70 cm×40 cm×30 cm blocks by a fully automatic yellow-storage block compression and packaging *** obtained blocks were packaged and sealed with plastic film,and placed in a freely ventilated place for more than 15 d of anaerobic fermentation,so as to obtain compressed fermented chestnut leaf block feed.[Results]Through the detection and analysis of nutritional components in the compressed fermented chestnut leaf block feed in the laboratory,the protein content was equal to or greater than 10.2%,which was 44.68%higher than that of unfermented chestnut leaf feed;the tannin content was equal to or greater than 638 mg/kg,which was 18.41%lower than that of the original feed;and the crude fiber content was equal to or greater than 19.5%,which was 14.09%lower than that of the original feed.[Conclusions]This study improves the palatability of chestnut leaf feed,increases the use efficiency of feed and reduces feeding *** is worth popularizing.

关键词： EM microbial liquid Chestnut leaf Compressed fermentation Fattening of mutton sheep

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Ecological adaptation strategies of annual plants in artificial vegetation-stabilized sand dune in Shapotou Region

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Science China Earth Sciences 2004年第z1期47卷 50-60页

作者： ZHANG Jingguang LI Xinrong WANG Xinping WANG Gang Shapotou Desert experimental Research station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Taking annual plant Eragrostis poaeides in the artificial vegetation-stabilized sand dune in the Shapotou experimental Research station as example, study has been done on the adaptation strategies of annual plants to random environment through fixed quadrat observations of population changes and fixed plant determinations of individual growth, seed germination,population dynamics, spatial distribution pattern of population, competition and regulation. During the growing season, the survival rate of annual plants depends on the precipitation intensity and precipitation duration which activate the germination of seeds. The optimal germination strategy of annual plants in this habitat during the growing season appears as continuous germination under suitable conditions. Such continuous germination is an adaptive characteristic of annual plants to random environment. In addition, the variation processes of population size and regulation mechanism of E. poaeoides are studied. Statistical results of natural population in four consecutive years show that water condition in the habitat is the leading factor affecting the population dynamics of E. poaeoides. During the establishment period E. poaeoides had a higher death rate, but in the middle to later period they could survive stably. Due to the limitation of soil moisture, the competition among individuals for water inevitably led to self-thinning phenomena. Under very arid condition, the survival curve of annual herbs entirely appears as Deevey Ⅲ type (C type), but under relatively adequate precipitation condition, the survival curve appears as intermediate type. The strategy of life history obviously appears as r-strategy. Plant species of r-strategy often occurs in the early succession stage of the communities. In the relatively adequate and evenly-distributed rainfall years, E. poaeoides population exhibited a density-dependent, i. e., survival rate increased with decrease in population density. The main pattern to re

关键词： Shapotou region Eragrostis poaeoides ecological adaptation strategy.

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Soil water and salt distribution under furrow irrigation of saline water with plastic mulch on ridge

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Journal of Arid Land 2013年第1期5卷 60-70页

作者： LiJuan CHEN Qi FENG Alxa Desert Ecohydrological experimental Research station Cold and Arid Regions Environmental and Engineering ResearchInstitute Chinese Academy of Sciences Lanzhou 730000 China

Furrow irrigation when combined with plastic mulch on ridge is one of the current uppermost wa- ter-saving irrigation technologies for arid regions. The present paper studies the dynamics of soil water-salt trans- portation and its spatial distribution characteristics under irrigation with saline water in a maize field experiment. The mathematical relationships for soil salinity, irrigation amount and water salinity are also established to evaluate the contribution of the irrigation amount and the salinity of saline water to soil salt accumulation. The result showed that irrigation with water of high salinity could effectively increase soil water content, but the increment is limited com- paring with the influence from irrigation amount. The soil water content in furrows was higher than that in ridges at the same soil layers, with increments of 12.87% and 13.70% for MMF9 （the treatment with the highest water salinity and the largest amount of irrigation water） and MMF1 （the treatment with the lowest water salinity and the least amount of irrigation water） on 27 June, respectively. The increment for MMF9 was gradually reduced while that for MMF1 increased along with growth stages, the values for 17 August being 2.40% and 19.92%, respectively. Soil water content in the ridge for MMF9 reduced gradually from the surface layer to deeper layers while the surface soil water content for MMF1 was smaller than the contents below 20 cm at the early growing stage. Soil salinities for the treatments with the same amount of irrigation water but different water salinity increased with the water salinity. When water salinity was 6.04 dS/m, the less water resulted in more salt accumulation in topsoil and less in deep layers. When water salinity was 2.89 dS/m, however, the less water resulted in less salt accumulation in topsoil and salinity remained basically stable in deep layers. The salt accumulation in the ridge surface was much smaller than that in the furrow bottom under this

关键词： water and salt transportation furrow irrigation saline water soil salinity soil water content

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Integrated multi-omics reveals the relationship between growth performance,rumen microbes and metabolic status of Hu sheep with different residual feed intakes

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Animal Nutrition 2024年第3期18卷 284-295页

作者： Yanzhen Zhang Xiaowei Zhang Dingren Cao Jinyong Yang Huiling Mao Lingling Sun Chong Wang College of Animal Science and Technology College of Veterinary MedicineZhejiang A&F UniversityHangzhou 311300China Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province Hangzhou 311300China Zhejiang Provincial Animal Husbandry Technology Promotion and Monitoring station of Breeding Livestock and Poultry Hangzhou 310021China Department of Animal Science Shandong Vocational Animal Science and Veterinary CollegeWeifang 261061China

Residual feed intake(RFI)is a metric that provides a more accurate measure of feed *** lower the RFI,the higher the feed *** changes in the host microbiome and metabolome contribute to the greater feed efficiency of low RFI(LRFI)*** aim of this study was to explore the differences in rumen microorganisms,rumen metabolites and plasma metabolites of Hu sheep with differing RFI through the microbiome and metabolome.A total of 80 Hu sheep were *** experiment consisted of a 15-d pretrial period and a 128-d experimental *** RFI in the experimental period was calculated for all sheep,and the sheep were screened into high RFI(HRFI,n=8)and LRFI(n=8)*** HRFI and LRFI sheep did not differ in their initial and final body weights,average daily gain and body measurements,but the dry matter intake of LRFI sheep was significantly decreased(28.4%,P<0.001).The sheep with LRFI had higher digestibility of crude protein(P=0.010)and ether extract(P=0.010)compared to HRFI *** concentrations of acetate(P=0.036),propionate(P=0.010),valerate(P=0.027)and total volatile fatty acids(P=0.048)in rumen of LRFI group were higher compared to HRFI *** results of 16S rDNA sequencing indicated that the sheep with LRFI had higher proportions of Prevotella genus in rumen liquid(P=0.031).The rumen metabolome and plasma metabolome results showed that the citrate cycle,pyruvate metabolism and alanine,aspartate and glutamate metabolism processes were more active for sheep in LRFI group,which provided more energy substrate such as malic acid,oxoglutaric acid and citric *** conclusion,sheep with LRFI can utilize feed more efficiently,and the more active energy metabolism pathway and the production of energy substances may account for the higher feed efficiency.

关键词： Feed efficiency Residual feed intake Rumen microbiome and metabolome Plasma metabolome

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Mycorrhizal fungi mitigate nitrogen losses of an experimental grassland by facilitating plant uptake and soil microbial immobilization

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Pedosphere 2024年第2期34卷 399-410页

作者： Yangyang JIA Marcel G.A.VAN DER HEIJDEN Alain Y.VALZANO-HELD Markus JOCHER Florian WALDER Postdoctoral Mobile station of Ecology College of Ecology and EnvironmentXinjiang UniversityÜrümqi 830046China Research Group Plant-Soil Interactions AgroscopeZürich 8046Switzerland Research Group Climate and Agriculture AgroscopeZürich 8046Switzerland Department of Plant and Microbial Biology University of ZürichZürich 8008Switzerland Research Group Soil Quality and Soil Use AgroscopeZürich 8046Switzerland

Nitrogen(N)is one of the most limited nutrients of terrestrial ecosystems,whose losses are prevented in tightly coupled cycles in finely tuned *** change-induced N enrichment through atmospheric deposition and application of vast amounts of fertilizer are now challenging the terrestrial N *** mycorrhizal fungi(AMF)are known drivers of plant-soil nutrient fluxes,but a comprehensive assessment of AMF involvement in N cycling under global change is still ***,we simulated N enrichment by fertilization(low/high)in experimental grassland microcosms under greenhouse conditions in the presence or absence of AMF and continuously monitored different N pathways over nine *** found that high N enrichment by fertilization decreased the relative abundance of legumes and the plant species dominating the plant community changed from grasses to forbs in the presence of AMF,based on aboveground *** presence of AMF always maintained plant N:phosphorus(P)ratios between 14 and 16,no matter how the soil N availability *** in plant N:P ratios due to the increased plant N and P uptake might thus be a primary pathway of AMF altering plant community ***,we constructed a comprehensive picture of AMF’s role in N cycling,highlighting that AMF reduced N losses primarily by mitigating N leaching,while N_(2)O emissions played a marginal *** mycorrhizal fungi reduced N_(2)O emissions directly through the promotion of N_(2)O-consuming *** underlying mechanism for reducing N leaching is mainly the AMF-mediated improved nutrient uptake and AMF-associated microbial *** results indicate that synergies between AMF and other soil microorganisms cannot be ignored in N cycling and that the integral role of AMF in N cycling terrestrial ecosystems can buffer the upcoming global changes.

关键词： N cycling N enrichment N uptake N:P ratio plant community structure symbiotic soil fungi

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A comprehensive approach for assessing the economic contribution of forage and livestock improvement options to smallholder farming enterprises

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Journal of Integrative Agriculture 2015年第8期14卷 1573-1580页

作者： Neil Mac Leod Scott Waldron WEN Shi-lin Agriculture Flagship Commonwealth Scientific and Industrial Research Organisation (CSIRO) University of Queensland Red Soils experimental station Chinese Academy of Agricultural Sciences

The importance of livestock production activities to improving the livelihoods of smallholder farming households and the efficiency of their underlying farming systems is increasingly recognized.A rapid increase in livestock numbers, especially beef cattle, and special purpose forages is being promoted for smallholder farms which have traditionally undertaken subsistence cropping activities or simple livestock rearing activities using low quality *** limited plantings of specialized forages combined with a poor knowledge of animal nutrition are a challenge to establishing sustainable livestock enterprises, much public policy and research is now being focused on the use of new forages and improved feeding practices.A number of economic studies have suggested that specialized forage growing and livestock feeding activities can make a positive contribution to smallholder *** studies have typically compared the total level of farm or household income with and without livestock *** attention is given to how much the new forage or livestock activities actually contribute to or draw resources from other farm activities to assess their real economic contribution to the enterprise, and the availability of simple tools to assist in making such assessments are *** paper describes a simple modelling approach that was developed for an Australian Centre for International Agricultural Research（ACIAR）-supported project to explore the real as opposed to apparent economic impact of integrating improved forages and livestock within smallholder farming systems in the Red Soils region of south-central *** of the model is demonstrated using a simple case study of a smallholder enterprise that plans to introduce a new beef cattle rearing activity to its existing farm activity *** case study highlights the importance of explicitly valuing transfers of resources between different farm activities to gauge the real contribution o

关键词： smallholder farming systems economics resource transfers opportunity costs economic profit

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