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Effects of urea plus nitrate pretreated rice straw and corn oil supplementation on fiber digestibility,nitrogen balance,rumen fermentation,microbiota and methane emissions in goats

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Journal of Animal science and Biotechnology 2019年第2期10卷 491-500页

作者： Xiumin Zhang Rodolfo F.Medrano Min Wang Karen A.Beauchemin Zhiyuan Ma Rong Wang Jiangnan Wen Lukuyu A.Bernard Zhiliang Tan Key Laboratory for Agro-ecological Processes in Subtropical Region National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry ProductionInstitute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125HunanChina University of the Chinese Academy of sciences Beijing 100049China College of Veterinary science and Medicine Central Luzon State UniversityScience City of Munoz3120 Nueva EcijaPhilippines College of Animal science and Technology Hunan Agricultural UniversityChangsha 410128People’s Republic of China Agriculture and Agri-Food Canada Lethbridge Research and Development CentreLethbridgeAlberta T1J 4B1Canada International livestock research institute POB 30709Nairobi 00100Kenya.

Background: Urea pretreatment is an efficient strategy to improve fiber digestibility of low quality roughages for ruminants. Nitrate and oil are usually used to inhibit enteric methane(CH4) emissions from ruminants. The objective of this study was to examine the combined effects of urea plus nitrate pretreated rice straw and corn oil supplementation to the diet on nutrient digestibility, nitrogen(N) balance, CH4 emissions, ruminal fermentation characteristics and microbiota in goats. Nine female goats were used in a triple 3 × 3 Latin Square design(27 d periods). The treatments were: control(untreated rice straw, no added corn oil), rice straw pretreated with urea and nitrate(34 and 4.7 g/kg of rice straw on a dry matter [DM] basis, respectively, UN), and UN diet supplemented with corn oil(15 g/kg soybean and15 g/kg corn were replaced by 30 g/kg corn oil, DM basis, UNCO).Results: Compared with control, UN increased neutral detergent fiber(NDF) digestibility(P < 0.001) and copies of protozoa(P < 0.001) and R. albus(P < 0.05) in the rumen, but decreased N retention(-21.2%, P < 0.001), dissolved hydrogen concentration(-22.8%, P < 0.001), molar proportion of butyrate(-18.2%, P < 0.05),(acetate + butyrate) to propionate ratio(P < 0.05) and enteric CH4 emissions(-10.2%, P < 0.05). In comparison with UN, UNCO increased N retention(+34.9%, P < 0.001) and decreased copies of protozoa(P < 0.001) and methanogens(P < 0.001). Compared with control, UNCO increased NDF digestibility(+8.3%, P < 0.001), reduced ruminal dissolved CH4 concentration(-24.4%, P < 0.001) and enteric CH4 emissions(-12.6%, P < 0.05).Conclusions: A combination of rice straw pretreated with urea plus nitrate and corn oil supplementation of the diet improved fiber digestibility and lowered enteric CH4 emissions without negative effects on N retention. These strategies improved the utilization of rice straw by goats.

关键词： Dissolved hydrogen Methane Nitrate Oil Rumen fermentation Urea

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ecological risk assessment of the Gannan Plateau,northeastern Tibetan Plateau

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Journal of Mountain science 2018年第6期15卷 1254-1267页

作者： YUE Dong-xia ZENG Jian-jun YANG Chao ZOU Ming-liang LI Kai CHEN Guan-guang GUO Jian-jun Xu Xiao-feng Meng Xing-min Key Laboratory of Western China＇s environmental Systems （Ministry of Education） College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Key Laboratory of Desert and Desertification Northwest Institute of Eeo-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China School of Management Lanzhou University Lanzhou 730000 China

Desertification, soil salinization and grassland degradation are the major environmental hazards faced by the Gannan Plateau, northeastern Tibetan Plateau. ecological risk assessment plays an important role in formulating environmental management strategies yet little attention to this region. In this study, we established an ecological risk assessment index system based on 30 evaluation indices in the categories of hydrometeorology, ecological environment, ground surface disturbance, and society and economy for the Gannan Plateau. An entropy method was used to calculate an index weight,and subsequently the matter-element method was used together with extension theory to establish a matter-element extension model of ecological risk. We assessed the ecological risk in this region by calculating the degree of association between index layer, system layer and target layer, and the cumulative ecological risk index. The degrees of ecological risk for the counties of the region were determined by using Arc GIS which would represent a spatial heterogeneity of the risk grade in production. Our results showed that the areas of high ecological risk were in Zhouqu County and Zhuoni County, and others were of low risk(Hezuo City, Diebu County, Xiahe County and Lintan County) or intermediate risk(Maqu County). The results of the assessment were in accord with the actual observed situation. Thus, our ecological risk assessment index system is appropriate for this region and suggests that high risk counties need a priori ecological protection. Such research could provide a technological support which would potentially prevent or reduce disasters by establishing an ecological barrier to promote the sustainable development of Gannan Plateau.

关键词： Matter-element Extension theory ecological risk assessment Ecosystem GannanPlateau

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Experience of Overseas Countryside Development and Construction of “Beautiful Countryside” in Zhejiang

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Journal of Landscape research 2014年第3期6卷 26-30,34页

作者： HUANG Shan WU Qianbo XU Ming Architectural design & research institute of Zhejiang University Co. Ltd. Department of Urban Planning Zhejiang University of Technology Hangzhou Urban Planning & Consultation Co. Ltd.

Countryside development paths and phase characters of typical developed countries and regions were analyzed,such as the East Asian Model(Japan and South Korea),and Western European Model(Germany and the Netherlands).The former is based on the big gap between urban and rural development,and the latter is based on the balanced development of urban and rural areas,both of them achieved the world’s leading level of countryside *** Zhejiang Province,"China’s Beautiful Countryside"represented by Anji,and"Zhejiang Green Agricultural Product Base"represented by Xianju emerged in the county *** mechanisms for countryside development in China and abroad were analyzed,including industrial system,infrastructure,ecological environment,and local culture.

关键词： Overseas countryside Balanced urban and rural development Beautiful countryside Zhejiang

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research on the Prevention and Control Methods for Forest Disasters in China's Forestry ecological environment Construction

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Agricultural Biotechnology 2022年第4期11卷 148-160页

作者： Yanrong CAI Xueqing ZHAO Qiuyu LAI Sichuan Water Resources and Hydroelectric Investigation and design research institute Co. Ltd.Chengdu 610072China China State Grid Sichuan Electric Power Company Construction Branch Chengdu 610072China

With the development of economy,China has gradually begun to pay attention to the protection of the natural *** the concept of"lucid waters and lush mountains are invaluable assets",importance has been attached to the development of forestry *** protection of forest resources and the prevention and control of disasters are important contents and necessary components in the construction of China's forestry ecological *** the analysis and research on the types of forest disasters(forest fires,biological disasters,meteorological disasters,geological disasters,deforestation)and disaster-causing factors,some basic countermeasures were put forward with the aim to enhance the production capacity of forest resources,improve the ecological environment of forest resources and prevent forest resource disasters.

关键词： Lucid waters and lush mountains Invaluable assets Forest disasters Disaster prevention and mitigation Basic countermeasures

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Flexible lithium metal capacitors enabled by an in situ prepared gel polymer electrolyte

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Chinese Chemical Letters 2021年第11期32卷 3496-3500页

作者： Qizhi Zhong Bao Liu Bingjun Yang Yali Li Junshuai Li Xingbin Yan Key Laboratoy of Special Function Materials Structure design of the Ministry of Education and School of Materials&EnergyLanzhou UniversityLanzhou 730000China Laboratory of Clean Energy Chemistry and Materials State Key Laboratory of Solid LubricationLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

The rapid development of next-generation flexible electronics stimulates the growing demand for flexible and wearable power sources with high energy *** metal capacitor(LMC),combining with a Li metal anode and an activated carbon cathode,exhibits extremely high energy density and high power density due to the unique energy storage mechanism,thus showing great potential for powering wearable electronic ***,a flexible LMC based on an in situ prepared PETEA-based gel polymer electrolyte(GPE)was reported for the first *** to the high ionic conductivity of PETEA-based GPE(5.75×10^(−3)S/cm at 20℃),the assembled flexible LMC delivers a high capacitance of 210 F/g at 0.1 A/g within the voltage range from 1.5 V to 4.3 V ***/Li^(+),a high energy density of 474 Wh/kg at 0.1 A/g and a high power density of 29 kW/kg at 10 A/*** importantly,PETEA-based GPE endows the LMC with excellent flexibility and safety,which could work normally under abuse tests,such as bending,nail penetration and *** in situ prepared PETEA-based GPE simplifies the fabrication process,avoids the risk of leakage and inhibits the growth of Li dendrite,making LMC a promising flexible energy storage device for the flexible electronic field.

关键词： Lithium metal capacitor In situ prepared gel polymer electrolyte Flexible Energy density Power density

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Agricultural ecological Capital: Factor Structure,Value Assessment and Accumulation Mechanism

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Meteorological and environmental research 2017年第6期8卷 1-5,14页

作者： Li Pingheng Yan Lidong Zhu Xiaorong Deng Yuanjian School of Business Administration Zhongnan University of Economics and Law Business School Wuhan Institute of Design and Sciences

As a kind of important new capital form,agricultural ecological capital plays a decisive role in guaranteeing healthy development of agricultural ecological economy. Therefore scientific understanding agricultural ecological capital is favorable for developing agricultural ecological economy,while clarifying factor structure,value assessment and accumulation mechanism of agricultural ecological capital is important content of understanding agricultural ecological capital. In this paper,factor structure of agricultural ecological capital is firstly elaborated,and it is thought that agricultural ecological capital is the unity of agricultural ecological environment,agricultural ecological resource and agricultural ecological system. Then agricultural ecological capital value is assessed according to use value method and non use value method,thereby realizing quantification of agricultural ecological capital. After agricultural ecological capital passes through value assessment,the value is more clear,which creates condition for agricultural ecological capital accumulation. Finally accumulation mechanism of agricultural ecological capital is analyzed. Accumulation channel of agricultural ecological capital is explored from natural and human factors,and it is found that agricultural ecological capital accumulates in the forms of agricultural ecological restoration and agricultural ecological compensation.

关键词： Agricultural ecological capital Factor Value Accumulation

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ecological Risks of Agricultural Land Capitalization and Their Prevention

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Journal of Landscape research 2017年第6期9卷 53-57,60页

作者： LI Pingheng YAN Lidong ZHU Xiaorong PAN Shilei School of Business Administration Zhongnan University of Economics and Law Business School Wuhan Institute of Design and Sciences

The capitalization of agricultural land as an institutional innovation in land use is of great significance to revitalize China's land resources, change land use and improve land use efficiency. With the gradual implementation of the capitalization of agricultural land, however, environmental problems brought by capitalization have restricted the sustainable and efficient utilization of agricultural land. This study, from the perspective of ecology, discusses ecological risks of agricultural land capitalization, analyzes the ecological risks of agricultural land capitalization in terms of the amount of land and land quality as well as the formation mechanism of the ecological risks of agricultural land capitalization. It is found that the logic of the capital itself, the profitability of the subject and the fragility of the ecological environment are the internal and external factors of the ecological risks of agricultural land. Thereupon authors put forward policy suggestions to prevent the ecological risks of agricultural land capitalization in terms of large-scale agricultural operations in diverse forms, the development of green agriculture, the protection of agricultural land quality and green finance, with a view to resolving the ecological risks of agricultural land capitalization and realizing the benign operation of agricultural land capitalization.

关键词： Agricultural land Capitalization ecological risks Risk prevention

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LANDSCAPE ecological CONSTRUCTION IN RURAL CHINA:THEORY AND APPLICATION

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Chinese Geographical science 2001年第2期11卷 104-114页

作者： XIAO Du-ning (Cold and Arid Regions environmental and Engineering research institute, the Chinese Academy of sciences, Lanzhou 730000, P.R.China institute of Applied Ecology,the Chinese Academy of sciences, Shenyang 110015,P.R.China ) Cold and Arid Regions environmental and Engineering research institute the Chinese Academy of Sciences Lanzhou P.R. China institute of Applied Ecology the Chinese Academy of Sciences Shenyang P. R. China

In landscape with overpopulation, intensive management for economic production, and where even small natural-vegetation patches are scarce, ecological conservation generally must be developed in the course of economic development. Thus “landscape ecological construction” has evolved in China. This approach adds spatial elements and alters landscape pattern to strengthen inter-ecosystem linkages, improve functioning of damaged ecosystems, and increase productivity and stability of the whole landscape. Five examples of managed landscapes in China are presented: dike-pond systems in a river delta; multi-pond system in a rice paddy landscape; field-grass-wood grid system on unstable sand dunes; shelterbelt network in a crop field area; and field-grass-wood mosaic system on highly erodible hilly farmland. These indicate that ecological conditions can be improved along with increased economic production. Altering landscape structure and ecological flows by introducing small landscape elements in distinct spatial patterns is considered a key to the results. This reshaping of the land has focused on changing patch size, regularity of arrangement, biological and hydrological corridors, and networks, the matrix and grain size. It suggests that such changes can increase negative feedbacks and increase stability. Finally, planning and design principles are pinpointed for the landscape ecological construction process.

关键词： landscape planning ecological construction rural China

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A Study on the Protection of Urban Fringe Habitat Units from the Perspective of the Actor-Network Theory

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China City Planning Review 2021年第3期30卷 6-18页

作者： Tang Xizi Lei Qiuyun Shenglin Elijah Chang Bi Linglan Zhang Yu Qian Fang(译) Liu Jian(校) School of Architecture and design Southwest Jiaotong UniversityChengduP.R.China Graduate institute Building&Planning National Taiwan UniversityTaipeiP.R.China 不详

Being an important part of a region’s ecological space,the habitat units on the urban fringe continuously provide multiple services for the city and its residents and guarantee the ecological security of the local *** composed of farmlands,secondary woodlands,ditches and ponds,etc.,they are typical semi-natural habitat which is subject to the influences of both the human society and the natural *** they involve multiple stakeholders and concern complex ownerships,top-down measures are difficult to be implemented,as presented by the Not-In-MyBackyard(NIMBY)phenomenon against protected *** on the Actor-Network Theory,this paper clarifies the intrinsic relationship between the maintenance of urban fringe habitat units and the relevant social *** the case study on Yilan’s practice of protecting and utilizing agricultural and forestry resources in Taiwan,China,the paper explores the community supported management and control strategies for the purposes of enhancing the protection of habitat units and promoting the effectiveness of regional services,which are implemented through the steps of implementing such translation methods as Obligatory Passage Point setting and benefit granting,recruiting and mobilizing relevant actors to form a network,and realizing the substantial protection of habitat units.

关键词： urban fringe habitat unit protection and utilization actor-network

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Study of spatial patterns and spatial effects of energy eco-efficiency in China

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Journal of Geographical sciences 2016年第9期26卷 1362-1376页

作者： GUAN Wei XU Shuting Center for Studies of Marine Economy and Sustainable Development Liaoning Normal University Dalian 116029 Liaoning China Collegeof Urbanand environment science Liaoning Normal University Dalian 116029 Liaoning China

Energy eco-efficiency is a concept integrating ecological and economic benefits arising from energy utilization and serves as a measure of efficiency in the energy-environment-economy system. Using the slacks-based measure （SBM） model considering undesirable output, this study first measures the energy eco-efficiency of provinces in China from 1997 to 2012. It then analyzes the spatial distribution and evolution of energy eco-efficiency from three aspects： scale, intensity, and grain of spatial patterns. Finally, it examines the spatial spillover effects and influencing factors of energy eco-efficiency in different provinces by means of a spatial econometric model. The following conclusions are drawn：（1） The overall energy ecofficiency is relatively low in China, with energy-inefficient regions accounting for about 40%. Guangdong, Hainan and Fujian provinces enjoy the highest energy eco-efficiency, while Ningxia, gansu, Qinghai, and Xinjiang are repre- sentative regions with low efficiency. Thus, the pattern of evolution of China＇s overall energy eco-efficiency is U-shaped. Among local regions, four main patterns of evolution are found： increasing, fluctuating, mutating, and leveling. （2） At the provincial level, China＇s energy eco-efficiency features significant spatial agglomeration both globally and locally. High-high agglomeration occurs mainly in the eastern and southern coastal regions and low-low agglomeration in the northwestern region and the middle reaches of the Yellow River. Changes in spatial patterns have occurred mainly in areas with high-low and low-high agglomeration, with the most remarkable change taking place in the Beijing-Tianjin-Hebei region. （3） There exist significant spatial effects of energy eco-efficiency among provinces in China. For the energy eco-efficiency of a given region spatial spillovers from adjacent regions outweigh the influence of errors in adjacent regions. Industrial structure has the greatest influence on energy eco-effic

关键词： energy eco-efficiency SBM model spatial pattern spatial econometric model

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