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Chinese Chemical Letters 2002年第3期13卷 219-222页

作者： XiangKaiFU yansui 等 CollegeofChemistryandChemicalEngineering Southwest－ChinaNormalUniversityChongqing400715 CollegeofChemistryandChemicalEngineering ChongqingUniversityChongqing400044

The polystyrenylphosphonous acid (PSPA) of low polymerization degree was prepared with one step reaction. The reaction mechanism was changed with different initiators. For the reaction with AIBN or BPO as the initiator, there are 2 or 3 series of radical reaction chains and 5 or 9 series of polystyrenyl products. The main products are PSPA without or with the fragment of the initiator H[CH(C6H5)-CH2]n-PO2H2 and C6H5CO2-[CH2CH (C6H5)]n-PO2H2 respectively.

关键词： Polystyrenylphosphonous acid (PSPA) low polymerization degree 2 2-azobisiso-butyronitrile (AIBN) benzoyl peroxide (BPO) reaction mechanism.

Dynamic Evolvement of Agricultural System and Typical Patterns of Modern Agriculture in Coastal China:A Case of Suzhou

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Chinese Geographical Science 2009年第3期19卷 249-257页

作者： ZHAI Rongxin LIU yansui Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Shandong Provincial Land Survey ＆ Planning Institute Jinan 250014 China

Based on dynamic theory of system, agriculture is a complex system composed by element, structure, function and development. Firstly, this paper analyzes their connotation and relationship, which could be simply described that in virtue of element integrating and structure optimizing, agricultural system may achieve multifunctionality to meet increasingly diverse demands. As a case study of Suzhou, it concludes that Suzhou has a LP-dependence on agricultural element, and the growth extent of agricultural productivity correlates to the ratio of agricultural labor reduc- ing rate to farmland reducing rate. Agricultural structure of Suzhou changed with time, and in the early 1980s and 2000s it was most notable. Correspondingly, agricultural function has experienced a succession process: 'production', 'production-living', and 'production-living-ecology'. At last, based on questionnaires and interviews, some new characteristics and problems of agricultural development in coastal developed region of China have been put forward. Meanwhile, some typical patterns of modern agriculture in Suzhou which adapt to system evolving are also brought up such as export-oriented agriculture, enterprises-leading agriculture, agricultural science and technology parks, characteristic and stereoscopic agriculture, tourism and sightseeing agriculture.

关键词： modern agriculture agricultural system Suzhou coastal China

Spatio-temporal Dynamic Patterns of Rural Area Development in Eastern Coastal China

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Chinese Geographical Science 2013年第2期23卷 173-181页

作者： LIU yansui WANG Guogang ZHANG Fugang Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences China Law Center for Land and Resource

The aim of this study is to evaluate the current state of rural area development at the county level in the eastern coastal China. An evaluation index system including 18 factors was developed, and a rural development index (RDI) was constructed to evaluate rural development state in 2000, 2004, and 2008. The quantitative evaluation indicated the following results. 1) This study derived four dominating components by means of principal component analysis, which can explain 78.2% of the total information, namely agricultural production input, the basic condition of agriculture, the comparative effectiveness of grain production, and the household′s own basic conditions. 2) Since the turn of the new millennium, the rural area in the eastern coastal China has experienced a rapid development in general. Well developed, developed, moderately developed and undeveloped rural areas respectively occupied 29.32%, 22.33%, 21.91%, and 10.51% in 2008. 3) The countryside had maintained a sound momentum of developing trend between 2000 and 2008, while the rural development in the eastern coastal China lacked sustainability. And 4) industrialization, urbanization, original economic basis, and location are four major driving forces of the disparity of rural area development in the eastern coastal China. Given these results, the strategies and policies for the improvement of each rural group were put forward.

关键词： rural area development rural development evaluation new countryside construction eastern coastal China

Optimizing field management to promote the ecologicalization of agriculture in loess hilly-gully region,China

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Journal of Geographical Sciences 2023年第5期33卷 1055-1074页

作者： HUANG Yunxin LI Yurui LIU yansui Institute of Geographic Sciences and Natural Resources Research CASBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing101408China National Observation and Research Station of Earth Critical Zone on the Loess Plateau in Shaanxi Xi’an710061China

Scientific field management is an important path to realize ecological production and sustainable development of *** the main content of field management,nitrogen(N)management is the key to balance the economic and ecological benefits of agricultural *** the loess hilly-gully region,for the fragile ecological and social system,ecologicalization of agricultural production is an important direction to promote sustainable agricultural ***,irrational fertilization has been one of the main constraint factors,hindering the ecologicalization of local *** order to solve the problem and prove the practical significance of field management to ecologicalization of agriculture,this study aimed at evaluating the effects of different N fertilization rates and timing using Root Zone Water Quality Model(RZWQM)and then optimizing the N *** were conducted from 2018 to 2019 in Yangjuangou watershed,loess hilly-gully region,to calibrate and validate the *** root mean square error(RMSE)of soil water content,nitrate N concentration,above-ground biomass,leaf area index ranged from 10.5-13.5 mm,2.96-3.80 mg·kg^(−1),730.3-1273.9 kg·ha^(−1)and 0.26-0.38,respectively,with the agreement index(d)between observed and simulated values ranging between 0.88 to *** results showed that N leaching in semi-arid areas was also quite high due to concentrated rainfall and loose soil,which had previously been *** the fertilization rate decreased by 35%(applying the chemical fertilizer at rate of 245.7 kg N ha^(−1))of typical fertilization(applying the chemical fertilizer at rate of 378.0 kg N ha^(−1)),the leaching and residual N decreased by 72.2%-75.4%and 35.6%-50.9%,respectively,while NUE increased by 41.5%-45.2%with no reduction in maize ***,compared with applying additional N at seedling stage in one batch,applying at seedling and jointing stages in two batches further decreased N leaching and

关键词： field management nitrogen fertilization ecologicalization of agriculture gully agriculture loess hilly-gully region

Characteristics and Mechanism of Agricultural Transformation in Typical Rural Areas of Eastern China:A Case Study of Yucheng City,Shandong Province

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Chinese Geographical Science 2010年第6期20卷 545-553页

作者： CHEN Yangfen LIU yansui XU Keshuai Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of SciencesBeijing 100101China

Rural off-farm employment,rapid loss of agricultural land,and advanced technology popularization had led agricultural production in Chinese typical rural areas come at a critical transformation and upgrade *** on sample survey data gathered from 401 households in Yucheng City,Shandong Province,this paper focuses on the characteristics and mechanism of agricultural transformation in typical rural areas of the eastern *** was found that 74.3% of households surveyed kept at least one member engaging in off-farm employment,and 57.1% looked forward to expanding the operational scale of arable land,while just 13.7% had actually transferred their agricultural *** growing off-farm employment does not result in the collapse of traditional subsistence agriculture,therefore,agricultural production in Yucheng City is at an incomplete transformation phase from traditional small-holder farming to modern scale *** is caused by both macro environments and family characteristics,while urban-rural dual structure,imperfect rural development policy and agricultural technology popularization make peasant economy strengthen upon maintenance,and small-holder farming becomes peasant's natural response owing to pluriactivity,local off-farm employment,reverse elimination,*** order to achieve smooth agricultural transformation of typical rural areas in the eastern China,it needs to promote professional differentiation among peasants,under clear policies adopted by central *** comprehensive services for agricultural production and improving production skills and knowledge of farmers who are still living in the countryside will effectively stimulate the process of agricultural transformation.

关键词： agricultural transformation off-farm employment arable land management Yucheng City China

Hollow Villages and Rural Restructuring in Major Rural Regions of China: A Case Study of Yucheng City, Shandong Province

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Chinese Geographical Science 2011年第3期21卷 354-363页

作者： SUN Hu LIU yansui XU Keshuai Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of Sciences Beijing 100101 China

The agricultural land resources of China are relatively limited because of its large ***,balancing the land use for industrialization,urbanization,and food security is a big *** recent years,rural hollowing in China has resulted in numerous of abandoned rural houses,and the areas with abandoned houses need to be restored into agricultural land with effective land consolidation *** study used the method of benefit-cost analysis and the data collected through field surveys conducted in Yucheng City in the northwest of Shandong Province in March 2009,to examine how hollow villages (HVs) to be created and how to solve the *** qualitative and quantitative analyses indicate following results.1) The situation of HVs is becoming increasingly severe under rapid industrialization and urbanization in Yucheng City.2) Poor infrastructure in rural areas and incomplete urbanization are the main factors that have led to the rural hollowing in many major rural regions of China.3) In order to resolve the problem caused by HVs and increase agricultural land,reconstructing rural communities in the countryside is necessary.4) A new mechanism in the provision of compensation funds by developed regions to the villages in less-developed regions must be established.

关键词： hollow villages (HVs) village regrouping rural restructuring Yucheng City

Sustainable poverty alleviation and green development in China’s underdeveloped areas

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Journal of Geographical Sciences 2022年第1期32卷 23-43页

作者： GUO Yuanzhi LIU yansui Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China

In 2020, the decisive victory of building a moderately well-off society in all aspects means that absolute poverty in rural China has been completely eliminated. Consolidating and expanding the achievements of poverty alleviation and establishing a long-term mechanism to solve relative poverty have become key issues in high-quality development of underdeveloped areas. In this study, human-earth system is employed to analyze the element composition, structural organization and functional state of underdeveloped areas. The results show that poverty in underdeveloped areas stems from the lack of the coupling and coordinating mechanism among human, economic, resource and environmental elements, which is not conducive to transforming the ecological advantages into the advantages of regional development. In the antipoverty stage, underdeveloped areas innovate the human-earth coupling and coordinating mechanism through a series of targeted measures, promote the organic combination of poverty alleviation, ecological conservation and sustainable development, and boost the transformation of regional development and the increase of farmers’ incomes. Focusing on the 14 th Five-year Plan(2021–2025) and the long-term goal of 2035, governments in underdeveloped areas should make full use of the policy support to explore scientific methods of modern governance and sustainable development. In particular, it is necessary to practice the concept that "clear waters and lush mountains are invaluable assets" and take the road of the ecologicalization of industry and the industrialization of ecology by establishing a policy system of "green land", "green people", "green industry" and "green right", thus building an endogenous growth mechanism of sustainable poverty alleviation and green development in China’s underdeveloped areas.

关键词： sustainable poverty alleviation green development human-earth system underdeveloped areas high-quality development ecological civilization

GIS-based Effect Assessment of Soil Erosion Before and After Gully Land Consolidation: A Case Study of Wangjiagou Project Region, Loess Plateau

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Chinese Geographical Science 2015年第2期25卷 137-146页

作者： LIU yansui GUO Yanjun LI Yurui LI Yuheng College of Resources Science and Technology Beijing Normal University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

The Loess Plateau is one typical area of serious soil erosion in the world. China has implemented ′Grain for Green′(GFG) project to restore the eco-environment of the Loess Plateau since 1999. With the GFG project subsidy approaching the end, it is concerned that farmers of fewer subsidies may reclaim land again. Thus, ′Gully Land Consolidation Project′(GLCP) was initiated in 2010. The core of the GLCP was to create more land suitable for farming in gullies so as to reduce land reclamation on the slopes which are ecological vulnerable areas. This paper aims to assess the effect of the GLCP on soil erosion problems by studying Wangjiagou project region located in the central part of Anzi valley in the middle of the Loess Plateau, mainly using the revised universal soil loss equation(RUSLE) based on GIS. The findings show that the GLCP can help to reduce soil shipment by 9.87% and it creates more terraces and river-nearby land suitable for farming which account for 27.41% of the whole study area. Thus, it is feasible to implement the GLCP in places below gradient 15°, though the GLCP also intensifies soil erosion in certain places such as field ridge, village land, floodplain, natural grassland, and shrub land. In short, the GLCP develops new generation dam land and balances the short-term and long-term interests to ease the conflicts between economic development and environmental protection. Furthermore, the GLCP and the GFG could also be combined preferably. On the one hand, the GFG improves the ecological environment, which could offer certain safety to the GLCP, on the other hand, the GLCP creates more farmland favorable for farming in gullies instead of land reclamation on the slopes, which could indirectly protect the GFG project.

关键词： gully land consolidation land-resource engineering revised universal soil loss equation(RUSLE) effect assessment Loess Plateau

Regional ecosystem services relationships and their potential driving factors in the Yellow River Basin,China

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Journal of Geographical Sciences 2023年第4期33卷 863-884页

作者： SHAO Yajing LIU yansui LI Yuheng YUAN Xuefeng Yellow River Institute of Shaanxi Province College of Urban and Environmental SciencesNorthwest UniversityXi'an 710127China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China School of Land Engineering Chang'an UniversityXi'an 710064China

The Yellow River Basin(YRB)occupies an important position in China’s socioeconomic development and ecological conservation *** the spatiotemporal characteristics of the relationships among multiple ecosystem services(ESs)and their drivers is crucial for regional sustainable development and human-earth system *** study simulated food production(FP),water yield(WY),net primary production(NPP),soil conservation(SC),and habitat quality(HQ)in the YRB from 2000 to 2020,and evaluated the spatial evolution and the relationship of ESs at the raster *** analysis was used to identify the impact of natural,socioeconomic,and landscape patterns on the relationship between *** results demonstrated that the average HQ per unit area decreased by 18.10%,while SC,NPP,WY,and FP increased by 42.68%,47.63%,30.82%,and 67.10%,respectively,from 2000 to *** relationship between ESs in the YRB was dominated by weak trade-offs and weak synergies at a temporal scale,with the trade-offs strengthened in the Upper Yellow River Basin(UYRB)and the Middle Yellow River Basin(MYRB),and synergies strengthened in the Lower Yellow River Basin(LYRB).At the spatial scale,the relationships between HQ and WY,HQ and SC,HQ and NPP,FP and SC,and FP and HQ were all dominated by trade-offs,while other ES pairs were mostly based on synergistic *** the YRB,the relationships among ESs were mainly influenced by human disturbance,precipitation,and land-use and exploitation ***,the trade-offs among ESs in the UYRB were primarily affected by precipitation,and those in the MYRB and LYRB by human *** heterogeneity of the landscape could also effectively promote synergies among *** study could provide insights into trade-offs and synergies among ESs and their driving forces and lay a foundation for ecological restoration and sustainable development of ESs in the YRB.

关键词： ecosystem services trade-offs and synergies redundancy analysis human-earth system coordination YellowRiverBasin

Quantitative Appraisement on Ecological Carrying Capacity in Coastal Rapid Developing Region of Hainan Province

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Chinese Journal of Population,Resources and Environment 2008年第2期6卷 87-92页

作者： Zhang Fugang Liu yansui Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China

The ecological carrying capacity,an important indica- tor to evaluate the sustainable development of the ecosystem, means the potential ability of the natural ecosystem to carry so- cioeconomic development while the ecosystem is *** is limited by the carrying capacity of natural resources and environ- ment and the elasticity of the *** will be greatly signifi- cant to study the ecological carrying capacity of Hainan Province, the first ecological province admitted by the State Environmental Protection Administration in *** only is the natural eco- system reflected,but also the effects of human activities are em- phasized by integrating the ecosystem health analysis into the ecological carrying capacity *** research results,using the Factor Analysis tools of software SPSS,indicate that the eco- logical carrying capacity of Hainan Province fluctuated obviously from 1996 to *** level of the ecological carrying capacity of Hainan Province was relatively high in 1996,and reached into trough from 1997 to *** has steadily ascended to be above the middle level since the 21st *** results also show that policy factors,especially the implementation of the 'Ecological Province' strategy,were important driving forces to influence the ecological carrying *** the population rapidly increas- ing,the land and water resources per capita have decreased *** amount of the ecological carrying capacity was pro- moted remarkably by socioeconomic development especially economic growth and technology *** of these will provide useful suggestions to establish and enact regional devel- opment policies,especially for protecting and reconstructing the ecology and environment of Hainan Province.

关键词： ecological carrying capacity evaluation driving forces Hainan Province