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  • Resources and Strategy
    LI Wei, YANG Cheng-xing, WANG Lu-cang, FENG Bin, QUAN Jin-zong
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    With the proposal of national spatial planning, China's urban-rural planning system has entered a new period of development, and the traditional national spatial development dominated by production space development has also turned to the new national spatial development, in which ecological, living and production spaces are coordinated. However, how to promote the cognition from the traditional national territorial area based on the concept of "Sansheng spaces" (production, living and ecological space) to the complex national attractive territorial area that enriches cultural context, ecological traits, and life foundation, balance the development priorities of different regions, so as to avoid blindly follow the single development model, are major themes facing both the central and local governments. From the perspective of the combination of history and reality, this paper, on the basis of reviewing the spatial cognitive process and rethinking the practice of spatial planning, clarifies the concept and connotation of "national attractive territorial area", puts forward the focus of "national attractive territorial area" in the national spatial planning system, as well as expounds the role and functionality of the "national attractive territorial area" from the aspects of balanced regional development, flexible management adjustment, spatial element flow, and development goal optimization.
  • Special Forum of "Ecological Restoration of Territorial Space"
  • Special Forum of "Ecological Restoration of Territorial Space"
    CHEN Xian-peng, FANG Kai, PENG Jian, LIU Ai-yuan
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    Maintaining the magnitude and intensity of human activities within the carrying capacity of resources and the environment is the core of the sustainable development theory. Therefore, how to assess the carrying capacity in a scientific way receives top priority among sustainability development strategies. The Planetary Boundaries Framework (PBF) that takes into account the Earth system as a whole provides new insights into assessing the carrying capacity of resources and the environment. The PBF has attracted considerable attentions and discussions within the sustainability science since its first appearance in the literature. However, the opportunities and challenges facing the PBF remain largely unexplored by the scientific community. This paper aims to fill in this gap by elaborating on the theoretical basis of the PBF and its conceptual evolution, revisiting the development and applications of the framework at the national, provincial, urban and organizational scales, identifying the challenges that the framework is facing and the solutions, and comparing the framework with the traditional paradigm for assessing the carrying capacity of resources and the environment. As a combination of historical experiences and scientific studies based on the theory of stable states and catastrophe in complex systems, the PBF serves as a useful supplement to the present assessments of carrying capacity. Primarily the downscaling of PBF to sub-global scales can be achieved through either top-down allocation or bottom-up integration. A systematic understanding of the linkages between these two pathways and their potential synergies would be of crucial significance to the development of the framework. However, we observe that there is a lack of clarity and transparency in the PBF regarding the scaling properties and interactions between various biophysical processes, leading to arguments over variables selection and boundaries setting. Besides, methodological challenges appear when we integrate PBF with tools for environmental impact assessment, such as environmental footprints and life cycle assessment, and extending the framework to socioeconomic dimensions. Therefore, there is a need for a deeper understanding of the PBF with respect to its theoretical basis, technical approaches and practical applications, so as to enhance the policy-guiding value of the framework as an approach to address the world's major public issues such as achieving Sustainable Development Goals (SDGs).
  • Special Forum of
  • Special Forum of
    LU Long-hui, CHEN Fu-jun, XU Yue-qing, HUANG An, HUANG Ling
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    Land use changes can affect the ecosystem services. Since the implementation of reform and opening-up policy in 1978, the transformation and development of society and economy has led to the land use transition, and furthermore led to the "ecosystem services transition". Based on the data of LUCC, net primary productivity (NPP) and statistics in 1980, 2000 and 2015, this paper analyzed the changes and spatial patterns of two types of ecosystem service, e.g., food production, carbon sequestration and oxygen release, in the Beijing-Tianjin-Hebei region by using the methods of GIS and ecosystem service values calculation, and revealed the reasons for the "ecosystem services transition". The results show that: (1) In the past 35 years, the land use changes in the study region was mainly characterized by the expansion of construction land and the decrease of cultivated land. The phenomenon of conversion of cultivated land to construction land was particularly prominent in this region. Between 1980-2000 and 2000-2015, the cultivated land in mountainous areas changed from decrease to increase and the forest land changed from decrease to increase. The cultivated land in dam areas continued to increase and the forest land changed from decrease to increase. Both the cultivated land and forest land in plain area continued to decrease. In 1980 and 2000, areas with high values of NPP were mainly located in mountainous areas, and in 2015, they were mainly found in plain areas. (2) From 1980 to 2000, the ecosystem services in the study area were mainly reflected by the increase of food production service and the decrease of carbon sequestration and oxygen production service. From 2000 to 2015, the ecosystem services in the region were mainly featured by the simultaneous increase of food production function and carbon sequestration and oxygen production function. The pattern of "ecosystem service transition" was "food production + carbon sequestration and oxygen production -" → "food production + carbon sequestration and oxygen production +". (3) The main reasons for "ecosystem services transition" were the improvement of agricultural productivity, the increase of area and quality of forest land, and the increase of the quality of cultivated land and grassland. In general, the "ecosystem services transition" in the Beijing-Tianjin-Hebei region has a positive impact on food security. It is particularly necessary to pay attention to areas where both food production function and ecological function declined. Policies aimed at improving agricultural productivity should be formulated, while policies for supporting ecological restoration should be continued.

  • Special Forum of "Ecological Restoration of Territorial Space"
  • Special Forum of "Ecological Restoration of Territorial Space"
    ZHAO Wen-zhen, HAN Zeng-lin, YAN Xiao-lu, ZHONG Jing-qiu
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    Taking Wafangdian county in Liaoning province as the research unit, on the basis of the evaluation of the four typical ecosystem services, including food supply, NPP, water yield and soil conservation in 2000 and 2014, OWA model was introduced to simulate the priority conversation areas of ecosystem services in the study area in 2014 as the ecological source. The MCR model was used to identify the ecological corridor and buffer zone, and the ecological security pattern of the study area was constructed. The results show that: (1) From 2000 to 2014, the spatial and temporal changes of ecosystem services in Wafangdian were significant. Except for water yield, other ecosystem services had been enhanced. (2) Considering the efficiency of ecosystem services protection (Ei>1) and trade-off degree (0.68), the priority conservation areas under scenario 5 were selected as the ecological source of Wafangdian. (3) The ecological source area of Wafangdian was 564.92 km2, which is distributed throughout the region; the total length of ecological corridors was 642.62 km, the first level corridors (220.76 km) ran through the north and south of the study area, and the secondary corridors (421.86 km) connected the dispersed ecological sources with net-like distribution. The results can provide decisive supports for sustainable ecosystem management and land use optimization in Wafangdian.
  • Special Forum of "Ecological Restoration of Territorial Space"
    ZHANG Rui, LIU Yan-xu, ZHAO Song, FU Bo-jie
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    As a special ecological and geographical region, the Tibetan Plateau provides various ecosystem services for the surrounding areas. Does the ecosystem service perceive differently from the public who have regional characteristic respectively? Meanwhile, would the regional difference influence the valuation of the Tibetan Plateau and ecological management measures? Based on 13254 questionnaires from 27 cities in China, this paper aims to value the ecosystem service and the drivers of public willingness to pay, and probe into the spatial heterogeneity in the above-mentioned verdict. The results show that: (1) The sorts of average maximum willing payment are: Northeast and North regions (1185.7 yuan/year) > Southeast coastal region (1021.1 yuan/year) > Northwest region (1012.3 yuan/year) > Central region (957.1 yuan/year) > Southwest region (894.7 yuan/year). (2) The allocation proportion sequence of ecosystem services is sorted as water conservation > carbon fixation > soil retention > biodiversity conservation > pollution decomposition > aesthetic existence. The allocation proportion of payment has no spatial heterogeneity in water conservation and aesthetic. The people in Northwest and Southwest regions are willing to pay more in soil retention, while those in Southeast coastal, Southwest and Central regions are willing to pay more compared with North region in pollution decomposition. It is difficult to grasp the spatial heterogeneity in carbon fixation and biodiversity conservation. (3) The drivers of public willingness to pay are ordered as ecosystem management attitudes > subjective indicators > objective indicators. (4) The types of ecosystem services and the level of urban development are the dominant factors for the regional differences of payment amount. The spatial difference has no influence on water conservation and aesthetic existence, and the objective indicators of the first-tier cities link less tighter to the payments than others do. Spatial distance only affected the correlation between biodiversity conservation and per capita monthly income. The findings can enhance the publicity of ecosystem management in the Tibetan Plateau.
  • Special Forum of "Ecological Restoration of Territorial Space"
    WANG Jie, BAI Wan-qi, TIAN Guo-hang
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    Ecological risk assessment is the foundation of prevention and control of ecological risks. Its development has experienced a process from environmental impact assessment to environmental risk assessment and then to ecological risk assessment gradually. With the further research on global change and ecological risk, more and more attention has been paid to the ecosystem risk caused by the change of land use. Therefore, ecological risk assessment of land use is also an important part of ecological risk research, which is the assessment of the possible adverse effects of the ecosystem under the direct or indirect impacts of land use. Through reviewing the existing researches, in this paper we summarize the progresses in methodology of ecological risk assessment of land use from three aspects: assessment model, spatial expression of ecological risk and uncertainty analysis. And we also expound the status and function of land use ecological risk management in land use ecological risk assessment. There exist three main problems in this field: (1) The evaluation index and standard of ecological risk assessment of land use are not unified; (2) There is great uncertainty with evaluation process and relevant result; (3) The research on ecological risk management is rather limited. The future trends of the study in this field include: (1) More attention should be paid to the ecological risk of land use under the background of global change, which needs to be more integrated with other fields of research and deal with the effect of ecological environment on global change; (2) The role of land use ecological risk assessment in land space planning and ecological restoration should be emphasized, which will give us a deep understanding of the current condition of the ecosystem and in an effort to maintain the sustainable development of the ecological environment; (3) The study of ecological risk management of land use is supposed to be strengthened, especially the link between risk management and assessment; (4) Ecological risk assessment and data management platform ought to be established and improved. It will standardize the risk index system, evaluation method and data acquisition, and reduce the uncertainty in the evaluation process effectively. What's more, our essay will enrich the theoretical system and provide related reference materials in this field.
  • Articles
  • Articles
    LIU Run-jia, BA Duo-xun
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    The compact urban construction is a new way to avoid the disorderly spread of the city, improve the quality of urban development and realize the efficient use of land resources. Therefore, it is essential to coordinate the relationship between urban compactness and urbanization level. Based on this, this paper takes 30 provincial capital cities and municipalities directly under the Central Government as the research object, and comprehensively uses the entropy method and capacity coupling coefficient model to measure the comprehensive level of provincial capital compactness and urbanization, and analyzes the coupling and coordination relationship between them. The results show that: (1) The compactness of China's provincial capitals continued to increase between 2006 and 2016. The compactness of the eastern provincial capitals was slightly higher than that of the central and western cities, showing the characteristics of the current situation of the east, the middle, and the west. (2) The city of compactness is gradually decreasing, and the number of the cities with medium and low compactness is increasing. (3) The relationship between compactness and urbanization of most provincial capital cities in China is mainly on the verge of coordination, and the overall transition changes from disordered state to coordinated state.
  • Articles
    SU Wei-zhong, MA Li-ya, CHEN Shuang, YANG Gui-shan
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    On the basis of the needs of national land space integration theory and method, the paper explores the system optimization method of urban ecological space adapting to the local development characteristics of China's rapidly urbanized areas. (1) Firstly, from the perspective of landscape or land composition based on CHANS (coupled human and nature system), the elements of urban ecological space system are deconstructed as ecological space and urban space. Then, the process framework of urban ecological space conflict analysis is established, which includes three aspects: conflict source, conflict area and conflict impact. The conflict source refers to the driving force of urban spatial growth and the source of ecological spatial change. The pressure of urban spatial change on ecological space results in the formation of ecological spatial conflict area under the conflict source. The consequences of various urban ecological functions (processes) are caused by conflict factors and conflict areas. Lastly, the way of system optimization is proposed based on the systematic diagnosis of conflict process and causes. (2) The case study of rapid urbanization shows that the first conflict source of social and economic activities in urban ecological space conflict is not prominent, and the policy driving force constitutes the main conflict source and runs through the whole conflict process. Through the analysis of road network and land layout planning process, the type and conflict mechanism of conflict area between urban and natural catchment areas are revealed, and the SWMM model is used to simulate and identify four flooding types and key causes. (3) Therefore, the system optimization objectives of urban ecological space are constructed respectively for conflict sources, conflict areas and conflict impact. The traditional optimization objectives aim at the drainage process and facilities formed by end-conflict impacts, and the core objectives aim at the key causes of formation of flooding areas, i.e. the enhancement of storage function and reconstruction of spatial elements in conflict areas of urban ecological space change. The fundamental optimization objectives aim is to change system, policy and planning of urban ecological space. The spatial optimization framework consisting of three types of main functional optimization areas, six types of key points and five types of key channels is identified for the case area. The framework of conflict analysis and the method of system optimization in the paper provide reference for the study of national land spatial integration. The case study covers the succession process of international stormwater management as a whole, which is helpful for the local understanding of the current large-scale land development transformation and the concept of sponge city construction.
  • Articles
    YIN Xu, LI Yu-rui, YUAN Tao, WANG Jing
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    Township is an important regional unit for the realization of new urbanization and rural vitalization in the new era. Both sustainable economic development and land use intensity are major issues in the new urbanization stage. Many concerns about the healthy development of towns are focused on the efficiency of economic development and the scale of land use. Therefore, the multi-factor comprehensive evaluation method was used to measure the level of economic development and land use intensity of 109 sampled towns in Jiangsu province. Furthermore, the correlation characteristics between land use intensity and economic development were discussed based on correlation analysis. The results show that: (1) The correlation of economic development and land use intensity of sampled towns is significantly positive (r=0.841, P<0.01), the better the economic development, the more intensive the land use. The "exponential growth" effect of increasing population size on economic development and land use intensity is more significant than the "linear growth" due to the expansion of built-up area. After the population size of towns reaches roughly 50 to 60 thousand, the level of economic development and land use intensity would accelerate significantly. (2) In terms of the average scores of economic development and land use intensity in different types of towns, as in economic regions, Southern Jiangsu > Central Jiangsu > Northern Jiangsu; in terms of development types, national key towns > non-key towns > xiang (township, a type of towns in China, more similar to rural community); as for industries, secondary industry > tertiary industry > balanced development industry > primary industry. (3) The degree of correlation between the two parts presents a differentiated feature. Southern Jiangsu has a significantly higher degree than Central and Northern Jiangsu; the larger the population in size, the higher the correlation between the two parts. However, the correlation caused by the increased built-up of towns is not obvious. Besides, the correlation degree of the national key towns is significantly higher than that of the non-key towns, and the correlation degree of balanced development industry and industry-oriented townships is relatively high, while that of agriculture-oriented townships is the lowest. The implications for the healthy development of towns is that the towns should focus on the coordination of plans, polarized development, enhance the attraction to population, and reach the ideal population threshold.
  • Articles
    SHAN Jing-zhu, LI Jing-mei, XU Zhi-hua
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    Protest response is a typical abnormal phenomenon in the research of contingent valuation method (CVM), which is against basic economic principles and may result in estimation bias of valuation of resource and environmental goods. The recognition of protest response and the reduction of impact on the willingness to pay will contribute to the improvement of estimation validity. Taking the willingness to pay for the governance of green tides in Jiaozhou Bay as an example, we chose protest belief as the proxy variable of protest response, screened motivation factors of protest belief in survey and studied the direction and degree of impact of these factors on willingness to pay. The results indicated that the respondents who were willing to pay for the governance of green tides showed protest belief and their protest belief was even higher in some items than that of respondents who were not willing to pay. The environmental concern variables, dilemma concern variables and warm glow variables had effects on the protest belief. We also found that the overall degree of protest belief had significant effects on the participation level as well as the extent of willingness to pay and the direction and degree of effects between these respondents were different, which verified that the participation and payment were different processes. The results will provide guidance for the optimal design of questionnaires, standardization of operational procedures and reduction of estimated bias of CVM.
  • Articles
    TIAN Hua-zheng, MA Li
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    As China's largest CO2 emission agency, industrial carbon emission reduction is crucial to achieving China's CO2 emission reduction goals. Apart from technical upgrading and adjustment of energy consumption structure, industrial restructuring should also be one of the important measures to decrease carbon emission intensity. To understand the relationship between industrial structure and industrial carbon emission intensity, this paper analyzed the CKC relationship between the output value of each department and its CO2 emissions based on Chinese industry and energy data from 1986 to 2016 by classifying 41 industrial sectors into 16 departments. Then, the carbon emission intensity of total industry output was decomposed into the carbon emission department structure, carbon emission factor, energy consumption intensity, and output structure with Kaya function. Further, contributions of four factors to the change of Chinese industrial carbon emission intensity were studied with LMDI method. At last, some conclusions were drawn as follows. Firstly, the relationship between the output and its CO2 emissions of different industrial departments is different. Only the wood processing and furniture manufacturing, papermaking and printing, stationery manufacturing and non-metallic mineral products industries have an inverted U-shaped relationship. The department of machinery/transportation/electrical/electronic equipment manufacturing has an inverted N-shaped relationship, and the remaining departments have a linear or monotonous increasing relationship. Secondly, the decline of energy consumption intensity is the outstanding factor and all departments show the same trend, while the contributions of output structure and carbon emission department structure show different trends of different departments. The capital and technology-intensive industries, such as non-metallic mineral products, chemical industry, pharmaceutical industry, machinery/transportation/electrical/electronic equipment manufacturing, wood processing and furniture manufacturing, show the significant technical reduction effects. The primary product processing industries, such as other manufacturing, oil and gas extraction, textiles and apparel, and chemical fiber and rubber and plastics industries, have significant structure reduction effects, while some energy industries, such as petroleum processing, coke and nuclear fuel processing, metal smelting and processing, and electricity gas and water producing and supplying industry, show a strong size and structure effect simultaneously. Therefore, China needs to formulate a scientific and reasonable industrial structure adjustment policy based on the characteristics of the relationship between the output value of various industrial sectors and its CO2 emissions.
  • Articles
    LU Yu-jia, CHEN Yang-fen
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    Overseas investment in agriculture is an important part of the Belt and Road Initiative (BRI). The research on the characteristics of USA's overseas investment in agriculture can provide scientific basis for a better use of domestic and international markets and resources, not only for drawing on USA's development experience, but also for responding and adapting to the investment behavior of major competitors. Based on the Outward Foreign Direct Investment theory, this paper adopts the logistic model and panel data analysis method to study the spatiotemporal pattern and influencing factors of USA's overseas investment in agriculture from 2000 to 2018, and discusses its policy implications for China's agricultural cooperation. The results show that: firstly, the USA's overseas investment in agriculture is mainly distributed on food processing and other pre- and post-production processes, mainly concerning developed countries such as Western European countries, as well as some neighbor developing countries such as Mexico and Brazil. Secondly, USA's overseas investment in agriculture showed a significant market orientation. In the meantime, it is also affected by geographical and cultural distance, national governance and other factors of the host country. Thirdly, in comparison of differences between China and the USA in characteristics of overseas investment in agriculture, considering the goal of China's international agricultural cooperation under the background of current international economic and trade situation, we suggested that China should further optimize the layout of agricultural industry chain, which will advance the implementation of sustainable development goals set by the United Nations and increase China's pricing power and channel control in the field of global food security. Furthermore we should explore the existing overseas agricultural investment market, reduce the geopolitical competition pressure and fully tap into potential market opportunities, focus on the agricultural technology demands of the BRI countries and region, and ensure that investment objectives are consistent with the investment demands of the host country. More importantly, it is necessary to solve practical problems faced with China's overseas investment in agriculture such as large cultural and institutional differences, which will improve the sustainability of agricultural cooperation projects under the BRI.
  • Articles
    LI Bo, ZHANG Wen-zhong, YU Jian-hui, LIU Qian-qian
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    This paper uses the entropy-weighted TOPSIS method to comprehensively evaluate the municipal economic development of prefecture-level cities in the Shanxi-Shaanxi-Inner Mongolia-Gansu-Ningxia (SSIGN) region. Then, it explores the spatio-temporal differentiation of economic development of the region using Markov transition probability analysis method and ESDA spatial analysis method. The results show that: (1) From 2005 to 2015, the gap in municipal economic development between cities in the SSIGN region was narrowed in the fluctuations, indicating that the municipal economic of the study region had not developed towards polarization, and there was a certain foundation for achieving coordinated development. (2) Each economic development grade city presented a diametrically opposite evolution law in different periods. Over time, all besides the lowest-grade cities had a higher risk of grade decline. This result indicates that for cities with higher municipal economic level, effective measures shoud be taken to improve their economic development sustainability. (3) From 2005 to 2010, to a certain degree, there was a significant spatial negative correlation between the economic levels of the cities in the SSIGN region. A positive interaction needs to be formed in this region. By 2015, this relationship was no longer significant. This result indicates that the municipal economic development of the region has improved in the direction of positive integration, but we still need to be alert to the problems of excessive homogenization and lack of effective interaction that have occurred in the historical development of this region. (4) The regional economic development of the SSIGN region has gradually emerged in the spatial pattern of the Golden Triangle consisting of Xi'an, Hohhot and Taiyuan. However, there has also been a clear cold spot in the study region. (5) The municipal economic development system in the cities of this region is generally in a state of low coupling coordination, and unbalanced economic development and uncoordinated are prominent. This result actually points out the key issue affecting the overall coordinated development of the region's economy. That is, the economic development subsystems within the city should also be a balanced system and coordinated development should be achieved among these subsystems.
  • Articles
    LI Li, HOU Guo-lin, XIA Si-you, HUANG Zhen-fang
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    Leisure tourism will be the future trend of tourism consumption, and leisure tourism resources are the carrier and foundation for the development of leisure tourism industry. Based on the POI data of Chengdu's leisure tourism resources, this paper aimed to analyze the spatial pattern and its influencing factors of leisure tourism resources in the city. We explored and analyzed the spatial distribution of leisure tourism resources using methods including Nearest Neighbor Hierarchical Clustering Analysis, Ripley's K function and Geographic Detector. The results show that: (1) The distribution pattern of Chengdu's leisure tourism resources is featured by central agglomeration and peripheral dispersion. The recreational, cultural, special and natural leisure tourism resources show the layout characteristics based on traditional business districts, cultural centers, green parks and natural attractions respectively. (2) There are different types of leisure tourism resources in terms of spatial scale. The largest spatial scale presents recreational and entertainment features, followed by special and cultural features, and the smallest one exhibits natural features. (3) Distance from the city center, tourist density, street vitality, resident density, resource endowment, road density, etc. are important factors influencing the spatial distribution of leisure tourism resources in the study area. (4) Among the influencing factors, the distance from the city center and the density of tourists and residents are the dominant factors; resource endowment and street vitality are the driving factors; road density, distance from main road and regional economic level are the predisposing factors; government behaviors and major events are the adjustment factors, and all these four factors form the spatial distribution pattern of leisure tourism resources in Chengdu.
  • Articles
    ZHANG Hai-peng, HE Ren-wei, LIU Yun-wei, FANG Fang
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    Taking Nagqu county in the alpine pasture of Tibetan Plateau as a case study, this paper built a land suitability evaluation index system of settlements, assessed the suitability of the land for the layout of settlements and its suitability grade in the study area using self-organizing mapping neural network (SOFM), evaluated the land suitability of current settlements, and further explored the paths of settlement reconstruction. The results showed that: (1) Nagqu county had a low level of land suitability for the layout of settlements. Suitable and sub-suitable areas, scattered in valleys with low elevations and flat terrain, only accounted for 12% of the total land area. Other areas of poorer suitability were relatively concentrated, accounting for 88% of the total land area. There were obvious differences among various townships and towns in the land suitability of settlements. (2) The current settlements of Nagqu county covered an area of 75.94 km2, accounting for only 0.47% of the total land area. Areas where the suitability level was generally suitable and above accounted for 86.47%. About 13.53% of settlement area was distributed in hardly suitable, unsuitable, or prohibited construction areas. The layout of settlements in various townships and towns tended towards high-grade suitability areas. The better the environmental conditions, the more reasonable the layout of settlements; and vice versa. Lack of planning guidelines, irrational setting of administrative villages, local identification with specific survival spaces, and worshipping of mountains by Tibetans all contributed to the unreasonable layout of settlements in Nagqu county. (3) Ecomigration, "village-oriented" development in suitable areas, and other promotion factors can be integrated to realize the spatial reconstruction of settlements. Through constructing the central villages and towns system supported by characteristic industries and giving full play to the element diffusion role of the "point-axis" system, restructuring can be promoted to achieve the economic restructuring of settlements. By means of improving the allocation of public service facilities, enhancing the degree of social organization, strengthening the inheritance of Tibetan culture, and promoting the optimization of other functions, the social restructuring of settlements will be accomplished.
  • Articles
    XU Hao, LIU Gang
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    Water option trading aims at solving the problem of uneven spatial and temporal distribution of water resources. With the change of global climate, rainfall has become an important factor leading to the uneven spatial and temporal distribution of water resources. In this paper, Markov chain is used to divide and forecast the rainfall scenarios. On the basis of rainfall forecast, the related costs of water option trading are determined. The forecast results of rainfall index are integrated into the determination of the ultimate overprice of water options. The improved Black-Scholes option pricing model is used to determine the rights of water options trading based on the forecast results of rainfall. Finally, the rationality of the calculation results is verified by using the extended linear expenditure model, which proves the rationality of the transaction price determined by the model. Taking Guangdong province as an example, this paper verifies the necessity of incorporating rainfall index into water option trading and the rationality of the related costs of water option trading determined by the model, and proves the superiority of fluctuating water price over stepped water price. Water option trading considering rainfall fully reflects the relationship between supply and demand in water market, and improves the scientificity of water option trading pricing in China.
  • Articles
    YANG Xin, MU Yue-ying
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    Although scarcity of irrigation water restricts grain production, it can promote agricultural technology progress to increase supply elasticities of grain. To shed light on the comprehensive effect of irrigation water pressure on grain production structure, this paper explores the effects of irrigation water pressure, grain price changes and their interaction on the yields of different crops based on heterogeneous coefficient Nerlove model and panel data of 27 provinces from 2002 to 2017. The results show that: (1) The direct effect of irrigation water pressure on grain production structure is increasing proportion of corn yield and reducing proportions of other crops yields. Specifically, the magnitude of that impact is in a descending order from rice, potatoes, beans and wheat. (2) The indirect effect of irrigation water pressure on grain production structure is decreasing supply elasticities of wheat, beans and potatoes while making supply elasticities of rice and maize even larger, which contributes to the increase of proportions of rice yield and corn yield. (3) With growth of irrigation water pressure from 2002 to 2017, its comprehensive effect on grain production structure makes a significant increase in proportion of corn yield and a significant decrease in proportions of beans yield and potatoes yield. Regional analysis reveals an increase in yield proportions of maize and rice in main grain production areas of Northern China, leading to more irrigation water consumption in this region where scarcity of water is severer. And this finding of our paper is a support for "the paradox of irrigation efficiency".
  • Articles
    YANG Jing-han, LIU Meng-yun, ZHANG Jie, ZHANG Meng-meng, CAO Run-shan, CAO Xin-yue
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    Studying the spatial variability and its affecting factors of surface soil organic matter and total nutrients can provide reference for soil management in the ecological fragile zone of the Loess Plateau. Based on the 93 soil sampling points in Wangdonggou watershed, this paper used a variety of geostatistical methods to analyze the spatial variability and its influencing factors of soil nutrients in the gully region of the Loess Plateau. The results showed that soil nutrient contents in the study area were at a moderate level. The spatial variability was in the following order: Total phosphorus > total nitrogen > organic matter > total potassium, and they were dominated by structural factors. Compared with total phosphorus and total potassium, organic matter and total nitrogen had smaller variation scale, weaker spatial autocorrelation and higher spatial complexity. Soil organic matter and total nitrogen presented a distribution pattern of high in the south and low in the north, and their main influencing factors included elevation, slope, curvature and land use. Total phosphorus was opposite to the former two, namely high in the north and low in the south. Elevation, slope, land use, soil mechanical composition and human activity had great influence on it. Total potassium was high in the center and low in the periphery, and its distribution was relatively scattered, and aspect and soil mechanical composition had a stronger effect on it. In view of the above results, regression prediction models between nine environmental factors and soil nutrients were established to provide data support for the sustainable use of soil resources in the study area.