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Withdrawal Intention of Farmers from Vacant Rural Homesteads and Its Influencing Mechanism in Northeast china: A Case Study of Jilin Province

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chinese Geographical Science 2023年第4期33卷 634-648页

作者： YU Jiaping LI Jing LO Kevin huang Shanlin Northeast institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China Department of Geography Hong Kong Baptist UniversityHong Kong 999077China School of Public Administration and Law Northeast Agricultural UniversityHarbin 150030China

The effective use of land in Northeast china is of great significance for ensuring national food security and regional rural *** this study,based on the survey data collected from Jilin Province,Northeast china,we analyzed the vacancy rates of rural homesteads in suburban,outer suburban,and remote villages,as well as the withdrawal intention of rural-settled farmers,urbansettled farmers,and farmers with urban and rural dual residency from vacant *** the perspective of farmers’perceptions,this study constructed a theoretical framework of the influence mechanism of their withdrawal intention and analyzed such mechanism by constructing a structural equation *** results indicated that:1)rural homestead vacancy rates increased with distance from the village to the city.2)rural-settled farmers showed a low withdrawal intention for vacant rural homesteads,followed by urban and rural dual-residence farmers,and urban-settled farmers showed the highest withdrawal intention.3)the relative importance of the factors influencing withdrawal intention is in the following order:policy awareness>interest perception>living environment perception>family ***,this study discussed the reformation of the homestead system and rural homestead transition in Northeast china,which can provide policy support to increase the potential of cultivated land and promote sustainable rural development and urban-rural coordination.

关键词： village hollowing vacant rural homesteads withdrawal intention influence mechanism Northeast china

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Relationship between nutrients and plankton biomass in the turbidity maximum zone of the Pearl River Estuary

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Journal of Environmental sciences 2017年第7期29卷 72-84页

作者： Zhen Shi Jie xu Xiaoping huang Xia Zhang Zhijian Jiang Feng Ye Ximei Liang Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Key Laboratory of Marginal Sea Geology Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China College of Animal Science and Technology Jiangxi Agricultural UniversityNanchang 330045China

Nutrients,dissolved and particulate organic carbon and plankton（bacterio-,phyto-and zoo-）were compared in the turbidity maximum zone（TMZ） and adjacent areas（non-TMZ） in the Pearl River *** results showed that high levels of suspended substances had marked effect on dynamics of nutrients and plankton in the *** on the cluster analysis of total suspended solids（TSS） concentrations,all stations were divided into two groups,TMZ with average TSS of 171 mg/L and non-TMZ of 45 mg/*** substances adsorbed PO^（3-）_4 and dissolved organic carbon,resulting in higher particulate phosphorus and organic carbon（POC）and lower PO^（3-）_4 and DOC in the TMZ,compared to the ***,suspended substances had limited effect on nitrogenous *** growth was light-limited due to high concentrations of suspended substances in the TMZ and a peak of phytoplankton abundance appeared in the *** contrast,the highest bacterial abundance occurred in the TMZ,which was likely partly responsible for low DOC *** peaks of zooplankton abundance observed in the TMZ and non-TMZ in the Pearl River estuary were primarily supported by bacteria and phytoplankton,*** finding implied that high levels of suspended solids in the TMZ affect the trophic balance.

关键词： Nutrient Plankton Turbidity maximum zone Pearl River estuary

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One size fits all? Contract farming among broiler producers in china

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Journal of Integrative Agriculture 2018年第2期17卷 473-482页

作者： huang Ze-ying xu Ying ZENG Di WANG Chen WANG Ji-min institute of agricultural Economics and Development Chinese Academy of Agricultural Sciences Centre for Global Food and resources University of Adelaide

Contract farming has been increasingly found to benefit smallholders in developing countries, yet much less is known about its role in the poultry industry where economies of scale could be more prominent. This study aims to narrow this gap by analysing the choice of contract farming among chinese broiler producers using a nationally representative survey. Simply cost-benefit analysis and multinomial logit regression modelling are jointly employed to explain contract farming decision making especially among small producers. In contrast to many recent studies, we find that small producers, though not passively excluded, usually opt out of contract farming due to limited profitability when large producers are coexistent. Such relationship is appropriately identified through a control function approach to correct for possible endogeneity. Therefore, contract farming may not help achieve higher welfare goals for small broiler producers who actually instead seek alternative market opportunities that better realise their comparative advantages.

关键词： contract farming broiler price multinomial logit china

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Development of an Agrobacterium-mediated CRISPR/Cas9 system in pea(Pisum sativum L.)

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The Crop Journal 2023年第1期11卷 132-139页

作者： Guan Li Rong Liu Rongfang xu Rajeev KVarshney Hanfeng Ding Mengwei Li Xin Yan Shuxian huang Juan Li Dong Wang Yishan Ji Chenyu Wang Junguang He Yingfeng Luo Shenghan Gao Pengcheng Wei xuxiao Zong Tao Yang National Key Facility for Crop Gene resources and Genetic Improvement/institute of Crop sciences Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Rice Genetic Breeding of Anhui Province Rice Research InstituteAnhui Academy of Agricultural SciencesHefei 230031AnhuiChina State agricultural Biotechnology Centre Centre for Crop and Food InnovationFood Futures InstituteMurdoch UniversityMurdochWA 6150Australia institute of Crop Germplasm resources Shandong Academy of Agricultural Sciences/Shandong Provincial Key Laboratory of Crop Genetic ImprovementEcology and PhysiologyJinan 250100ShandongChina Zhejiang Xinnan Chemical Industrial Group Co. Ltd.Hangzhou 311300ZhejiangChina State Key Laboratory of Microbial resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Pea(Pisum sativum L.)is an annual cool-season legume *** to its role in sustainable agriculture as both a rotation and a cash crop,its global market is expanding and increased production is urgently *** both technical and regulatory reasons,neither conventional nor transgenic breeding techniques can keep pace with the demand for increased *** answer to this challenge,CRISPR/Cas9 genome editing technology has been gaining traction in plant biology and crop breeding in recent ***,there are currently no reports of the successful application of the CRISPR/Cas9 genome editing technology in *** developed a transient transformation system of hairy roots,mediated by Agrobacterium rhizogenes strain K599,to validate the efficiency of a CRISPR/Cas9 *** optimization resulted in an efficient vector,*** used this optimized CRISPR/Cas9 system to edit the pea phytoene desaturase(PsPDS)gene,causing albinism,by Agrobacterium-mediated genetic *** is the first report of successful generation of gene-edited pea plants by this route.

关键词： Agrobacterium-mediated transformation CRISPR/Cas9 Pea Genome editing

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呼伦贝尔岭东地区野生大豆资源分布和种群生境调查研究

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中国野生植物资源 2024年第6期43卷 91-96页

作者：肖燕子王旭张宏斌黄学文姜超刘欣雨何立超邓庆山风润呼伦贝尔学院草产业协同创新研究中心内蒙古呼伦贝尔021000 中国农业科学院农业资源与农业区划研究所/内蒙古呼伦贝尔草原生态系统国家野外科学观测研究站北京100081 农业农村部农业生态与资源保护总站北京100000 呼伦贝尔市农畜产品质量安全中心内蒙古呼伦贝尔021000 内蒙古索尔奇国家湿地公园管理局内蒙古呼伦贝尔021000 海拉尔区农牧技术推广中心内蒙古呼伦贝尔021000

目的:通过对呼伦贝尔岭东地区野生大豆(Glycine soja Sieb.)种质资源分布、种群生境及样方内物种组成进行考察、搜集和整理,为该地区野生大豆资源开发、利用和保护提供参考依据。方法:采用野外调查、植物样本采集、资料文献收集等,分析... 详细信息

目的:通过对呼伦贝尔岭东地区野生大豆(Glycine soja Sieb.)种质资源分布、种群生境及样方内物种组成进行考察、搜集和整理,为该地区野生大豆资源开发、利用和保护提供参考依据。方法:采用野外调查、植物样本采集、资料文献收集等,分析了野生大豆地理分布特征、伴生植物组成及生长状况,并对保护区和非保护区野生大豆保护情况进行了对比分析。结果:呼伦贝尔岭东地区野生大豆大多分布在湿地、池塘、水稻田边机耕路、大豆田边、铁道旁边等地势低洼处,零星分布,也有连片成为群落的。野生大豆在湿地公园区域内株丛数和盖度排序第一,株高平均值为48 cm。伴生植物披碱草(Elymus dahuricus Turcz.)(83丛、盖度7%)、长萼鸡眼草(Kummerowia stipulacea Maxim.)(62丛、盖度3%)、问荆(Equisetum arvense L.)(52丛、盖度16%)占位优势种。结论:呼伦贝尔地区野生大豆资源较丰富,发展提升空间大,但是对其重要性的认识不到位,造成野生大豆破坏现象十分严重,本次调查为该地区的野生大豆资源的保护和科学利用提供参考依据。

关键词：呼伦贝尔岭东地区野生大豆资源调查

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生育期对燕麦全株产量和营养价值的影响

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草业科学 2024年第7期41卷 1720-1728页

作者：那亚陶雅李峰花梅徐丽君李文龙乌仁曹内蒙古农业大学草原与资源环境学院/草地资源教育部重点实验室/农业农村部饲草栽培、加工和高效利用重点实验室内蒙古呼和浩特010011 中国农业科学院草原研究所内蒙古呼和浩特010019 中国农业科学院农业资源与农业区划研究所北京100081 内蒙古鄂尔多斯市乌审旗林业和草原局内蒙古鄂尔多斯017300

观测15个燕麦(Avena sativa)品种的产量和营养品质等指标,研究不同生育期对不同燕麦品种全株产量和营养价值的影响,为鄂尔多斯地区引进高产优质的燕麦品种提供科学参考依据。结果表明:1)在灌浆期、乳熟期和蜡熟期干草产量最高的品种分... 详细信息

观测15个燕麦(Avena sativa)品种的产量和营养品质等指标,研究不同生育期对不同燕麦品种全株产量和营养价值的影响,为鄂尔多斯地区引进高产优质的燕麦品种提供科学参考依据。结果表明:1)在灌浆期、乳熟期和蜡熟期干草产量最高的品种分别是‘爱沃256’‘领袖’和‘黄燕麦’;2)粗蛋白含量在灌浆期、乳熟期和蜡熟期最高的品种分别是‘爱沃256’‘青引2号’和‘甜燕麦’;3)粗灰分含量在灌浆期、乳熟期和蜡熟期最低的品种分别是‘青引1号’‘白燕7号’和‘黄燕麦’;4)‘青引2号’的中性洗涤纤维含量在灌浆期最低,蜡熟期和乳熟期最低的品种均是‘白燕7号’;5)在灌浆期、乳熟期、蜡熟期酸性洗涤纤维含量最低的品种均是‘白燕7号’;6)随着生育期的推移,‘白燕7号’的干草产量先降低后增加,粗蛋白含量无显著变化,酸性洗涤纤维和中性洗涤纤维含量显著下降。综合分析得出,‘白燕7号’可作为鄂尔多斯地区高产优质的燕麦品种进行推广种植,其最适刈割期为蜡熟期。

关键词：燕麦生育期品种产量营养成分引种鄂尔多斯

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Identification of commercial cultivars of Agaricus bisporus in china using genome-wide microsatellite markers

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Journal of Integrative Agriculture 2019年第3期18卷 580-589页

作者： WANG Li-ning GAO Wei WANG Qiong-ying QU Ji-bin ZHANG Jin-xia huang Chen-yang Key Laboratory of Microbial resources Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China

Agaricus bisporus is one of the most widely cultivated mushrooms in the world. Commercial cultivars are usually phenotypically alike and easy to be copied by isolating tissue cultures. This brings great challenges to distinguish different cultivars and to protect new varieties. Thus, techniques for the accurate identification of cultivars are essentially required. In this study, we accurately identified 11 commercial cultivars of A. bisporus released in china by using microsatellite(SSR, simple sequence repeat) markers. SSR markers were developed by mining the genome sequence. A total of 3 134 SSRs were identified, of which 1 490 SSRs were distributed in gene models, and 1 644 in the intergenic regions. A total of 17 polymorphic primer pairs were developed and SSR fingerprints were constructed for all the commercial cultivars. These SSR markers generated a total of 73 alleles, with an average of 4.29 per locus. Specifically, the primer combination of AB_SSR_2341 and AB_SSR_2590 could distinguish all the 11 commercial cultivars. The similarity coefficients of the 11 commercial cultivars were between 0.56 and 0.95 indicating that some of them were close related. Our results provide an efficient technique for the identification of A. bisporus cultivars in china, which can also facilitate the marker-assisted breeding in the future.

关键词： Agaricus bisporus SSR strain identification fingerprint

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Determining the optimum range of soil Olsen P for high P use efficiency, crop yield, and soil fertility in three typical cropland soils

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Pedosphere 2020年第6期30卷 832-843页

作者： Qihua WU Shuxiang ZHANG Gu FENG Ping ZHU Shaomin huang Boren WANG Minggang xu institute of agricultural resources and regional planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081China Guangdong Provincial Bioengineering institute (Guangzhou Sugarcane Industry Research Institute)/Guangdong Key Laboratory of Sugarcane Improvement and BiorefineryGuangzhou 510316China College of resources and Environmental sciences China Agricultural UniversityBeijing 100094China Centre of agricultural Environment and resources Jilin Academy of Agricultural SciencesChangchun 130033China institute of Plant Nutrition Resources and EnvironmentHenan Academy of Agricultural SciencesZhengzhou 450002China

Soil Olsen P level has a major influence on crop yield,efficient P utilization,and soil *** this study,the optimum Olsen P range was determined from long-term(1990–2012)field experiments in three typical soil types of china under single cropping of maize or double cropping of maize and *** critical soil Olsen P value for crop yield was evaluated using three different models,and the relationships among P use efficiency(PUE),Olsen P,and total P were *** agronomic critical soil Olsen P values obtained from the three models for the neutral soil of Gongzhuling and the calcareous soil of Zhengzhou were similar;however,the values from the linear-linear and linear-plateau models for both maize and wheat were substantially lower than those from the Mitscherlich model for the acidic soil of *** PUE response change rates(linear equation slopes)under different soil Olsen P levels were small,indicating slight or no changes in the PUE as the soil Olsen P increased in all three soils.A comparison of the Olsen P levels that achieved the maximal PUE with the agronomic critical values derived from the three models indicated that the linear-plateau model exhibited the best *** regression equation coefficients of Olsen P response to total P decreased as follows:Zhengzhou(73 mg g-1)>Qiyang(65 mg g-1)>Gongzhuling(55 mg g-1).The Olsen P level increased as the total P increased,which may result in a decrease in *** achieve a relatively high crop yield,PUE,and soil fertility,the optimum Olsen P range should be 13–40,10–40,and 29–40 mg kg-1 at Gongzhuling,Zhengzhou,and Qiyang,respectively.

关键词： critical Olsen P value efficient P utilization long-term fertilization P management response curve soil type

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Increasing Winter Conductive Heat Transfer in the Arctic Sea-ice-covered Areas: 1979–2014

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Journal of Ocean University of china 2017年第6期16卷 1061-1071页

作者： FAN Xieyu BI Haibo WANG Yunhe FU Min ZHOU xuan xu Xiuli huang Haijun Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and Environmental Science Fujian Agriculture and Forestry University Fuzhou 350002 P. R. China Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of SciencesQingdao 266071 P. R. China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266200 P. R. China National Marine Environmental Forecasting Center Beijing 100081 P. R. China institute of Electronics Chinese Academy of Sciences Beijing 100190 P. R. China University of chinese academy of sciences Beijing 100049 P. R. China

Sea ice is a quite sensitive indicator in response to regional and global climate changes. Based on monthly mean PanArctic Ice Ocean Modeling and Assimilation System(PIOMAS) sea ice thickness fields, we computed the conductive heat flux(CHF) in the Arctic Ocean in the four winter months(November–February) for a long period of 36 years(1979–2014). The calculated results for each month manifest the increasing extension of the domain with high CHF values since 1979 till 2014. In 2014, regions of roughly 90% of the central Arctic Ocean have been dominated by the CHF values larger than 18 Wm^(-2)(November–December) and 12 Wm^(-2)(January–February), especially significant in the shelf seas around the Arctic Ocean. Moreover, the population distribution frequency(PDF) patterns of the CHF with time show gradually peak shifting toward increased CHF values. The spatiotemporal patterns in terms of the trends in sea ice thickness and other three geophysical parameters, surface air temperature(SAT), sea ice thickness(SIT), and CHF, are well coupled. This suggests that the thinner sea ice cover preconditions for the more oceanic heat loss into atmosphere(as suggested by increased CHF values), which probably contributes to warmer atmosphere which in turn in the long run will cause thinner ice cover. This represents a positive feedback mechanism of which the overall effects would amplify the Arctic climate changes.

关键词： conductive heat flux sea ice Arctic Ocean

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基于FY-3D卫星的微波与光学陆表温度融合研究

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气象 2024年第1期50卷 1-17页

作者：刘勇洪翁富忠徐永明韩秀珍段四波唐世浩叶成志中国气象局地球系统数值预报中心北京100081 灾害天气国家重点实验室北京100081 南京信息工程大学遥感与测绘工程学院南京210044 国家卫星气象中心北京100081 中国农业科学院农业资源与农业区划研究所北京100081 湖南省气象局长沙410118

目前还没有基于国产卫星的1 km分辨率的全天候陆表温度(LST)产品,FY-3D卫星提供了中分辨率成像仪(MERSI)Ⅱ型1 km分辨率晴空LST产品与微波成像仪(MWRI)25 km全天候LST产品,因此可结合两者优势开展全天候1 km分辨率LST的融合研究。基于... 详细信息

目前还没有基于国产卫星的1 km分辨率的全天候陆表温度(LST)产品,FY-3D卫星提供了中分辨率成像仪(MERSI)Ⅱ型1 km分辨率晴空LST产品与微波成像仪(MWRI)25 km全天候LST产品,因此可结合两者优势开展全天候1 km分辨率LST的融合研究。基于地理加权回归(GWR)方法,选择海拔、FY-3D归一化植被指数和归一化建筑指数等建立GWR模型对FY-3D/MWRI 25 km LST降尺度到1 km,并与MERSI 1 km LST进行融合;同时针对MWRI轨道间隙,利用前后1天融合后的云覆盖像元1 km LST进行补值,可以得到接近全天候下的1 km LST。基于以上融合算法,选择了中国区域多个典型日期FY-3D/MERSI和MWRI LST官网产品进行了融合试验,并利用公开发布的全天候1 km LST产品(TPDC LST)对FY-3D 1 km LST融合结果进行了评估。研究结果表明,基于GWR法的LST降尺度方法,可以有效避免传统微波LST降尺度方法中存在的“斑块”效应和局地温度偏低等问题;LST融合结果有值率从融合前的22.4%~36.9%可提高到融合后69.3%~80.7%,融合结果与TPDC LST的空间决定系数为0.503~0.787,均方根误差为3.6~5.8 K,其中晴空为2.6~4.9 K,云下为4.1~6.1 K;分析还表明目前官网产品FY-3D/MERSI和MWRI LST均存在缺值较多与精度偏低等问题,显示其存在较大改进潜力,这有利于进一步改进FY-3D LST融合质量。

关键词： FY-3D MERSI-Ⅱ FY-3D MWRI 全天候陆表温度地理加权回归

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