Loading...

Table of Content

    20 December 2018, Volume 33 Issue 12 Previous Issue    Next Issue
    Study on the Matching Pattern of Water and Potential Arable Land Resources in China
    SUN Zhen, JIA Shao-Feng, YAN Jia-Bao, ZHU Wen-Bin, LIANG Yuan
    2018, 33 (12):  2057-2066.  doi: 10.31497/zrzyxb.20171204
    Abstract ( )   HTML ( )   PDF (14575KB) ( )   Save
    Most previous studies have focused on the matching pattern of actual arable land and water resources in China. However, due to the lack of valid data about potential arable land resources, the matching pattern of potential arable land and water resources has seldom been investigated. In this paper, based on the potential arable land resources retrieved from remote sensing data, the matching degree of potential arable land resources with water resources in China was evaluated by using two indexes, i.e., water resource per unit area and Gini coefficient. First of all, according to the filter conditions suitable for crop cultivation, the spatial distribution of potential arable land area in China was retrieved from three indexes including DEM, slope and soil type. Then, the water resource per unit area of potential arable land in China were calculated, and the spatial matching degree of the raw water and soil resources in China was evaluated. Finally, we drew the Lorenz curve of water and land resources, calculated the Gini coefficient, and evaluated the overall matching pattern of water resource with potential arable land resource in China. The results showed that: 1) The potential arable land varied greatly in China that the area of potential arable land in northern China was much larger than that in southwestern China and east coastal regions. This indicated that in the future the potential arable land would be mainly located in the northern region. 2) There was a serious mismatching between the water resource and potential arable land resource in China. 3) The matching degree of water resource with potential arable land resource was extremely poor. About 80% of water resource served less than 23% of potential arable land in China. The Gini coefficient of water resource with arable land resource which was 0.712 in the whole country, was much higher than that of agricultural water use with farmland resources, which was 0.566. The matching degree of agricultural water and farmland resource was better than that of potential arable land and water resource, which was the result of human activities. This indicated that the Gini coefficient, calculated by the potential arable land without considering the water resource restriction, was much more suitable for expressing the matching degree of water and land resources. This study can provide scientific basis for us to take effective measures to adapt to the background matching pattern.
    References | Related Articles | Metrics
    Resource Utilization and Management
    Spatial-temporal Variations and Influential Factors of Land Transfer in China
    WANG Jia-yue, LI Xiu-bin, XIN Liang-jie
    2018, 33 (12):  2067-2083.  doi: 10.31497/zrzyxb.20171215
    Abstract ( )   HTML ( )   PDF (9886KB) ( )   Save
    Improving the efficiency of agricultural production and developing moderate scale management are the directions of China's agricultural development at present, and land transfer is the main way to realize the scale management of land in China in the system of collective ownership. Based on detailed analysis of spatial-temporal variation characteristics of land transfer in China, this paper used factor analysis method to explore the factors affecting land transfer at the provincial scale. The results showed that: 1) At present, China's land transfer is developing rapidly, but the regional differences are obvious. The land transfer rate increased rapidly from 5.2% in 2007 to 33.3% in 2015. In 2007, only 4 million hectares of cultivated land were transferred. In 2015, 30 million hectares of cultivated land were involved in land transfer. The scale of land transfer increased by 6 times in 8 years, and 3 million hectares of cultivated land were added to the land transfer process every year. The southern and western regions have slower transfer speed and smaller transfer scale, while the transfer speed is much faster and the scale is much larger in plains. 2) The promotion effect of land transfer on scale management (management scale > 3.33 hm2) is not obvious yet. The ratio of scale management is still at a low level that only 1.42% famers have management scale bigger than 3.33 hm2, and the management scale of cultivated land of 80% farmers is below 0.67 hm2. The fragmentation of land has a great hindrance to the realization of the land transfer effects. 3) Land resource endowment, economic development level, transfer transaction cost, land ownership stability, peasant households' willingness of land transfer and traffic accessibility are the most important factors that affect the development of land transfer. Land resource endowment, economic development level and land ownership stability are positively related to land transfer, and transaction cost is negatively related to land transfer. 4) There exist regional differences of the maturity of land transfer conditions in China. Heilongjiang, Inner Mongolia and Jilin have the highest maturity of land transfer conditions, and the maturity of land transfer conditions in Guizhou, Yunnan and Guangxi are the lowest. There are policy implications that the high transaction cost in China hinders the realization of land transfer effect and land fragmentation is an important cause of the increase of transaction costs. Carrying out the reform of the rural land system and promoting the farmland contracting rights in a certain area can promote the concentration of small plots, effectively reduce the transaction costs of land transfer and increase the scale of farmers' land management. At the same time, the regional differences of the maturity of land transfer conditions and the major limiting factors of land transfer should be paid attention in the formulation of policies that promote land transfer. Policies should be formulated by regions to solve the land transfer barriers, and moderate scale management fit for local condition should be encouraged.
    References | Related Articles | Metrics
    Resource Ecology
    Spatiotemporal Variation of the Vegetation Coverage in Yangtze River Basin during 1982-2015
    ZHANG Liang, DING Ming-jun, ZHANG Hua-min, WEN Chao
    2018, 33 (12):  2084-2097.  doi: 10.31497/zrzyxb.20171056
    Abstract ( )   HTML ( )   PDF (22337KB) ( )   Save
    Given the indication function of vegetation to climate change in many ways, quantification of vegetation coverage change and its coupling relationship with climate change has become the central topic in current global change and terrestrial ecosystem researches. In the present study, GIMMS (Glaobal Inventory Modelling and Mapping Studies) -NDVI (Normalized Difference Vegetation Index) and meteorological data during 1982-2015 were used to investigate the spatiotemporal change of vegetation coverage and its relationship with climate change and human activities in Yangtze River Basin (YRB) based on trend analysis, mutation analysis, partial correlation analysis and residual analysis. The results showed that: 1) Except for Min and Tuo River Basin, the vegetation coverage in the study area which accounts for 69.77% of the YRB was in rising tendency during 1982-2015, and 45.09% of the rising area it showed a significant increasing trend. 2) Based on the Mann-Kendall mutation analysis, we found that there were mutations of the interannual variation of vegetation coverage in the YRB during 1982-2015, however, there were regional differences of the mutation. 3) The vegetation coverage change was more sensitive to variations of temperature than other influencing factors, which suggests that temperature was the dominant factor affecting the change of vegetation cover in YRB. 4) According to residual analysis, the influence of human activities on vegetation coverage in the YRB is increasingly enhanced. Areas with weakening human activities mainly distributed in the Chin-sha River Basin, Min and Tuo River Basin, Hanshui River Basin and some provincial capital cities.
    References | Related Articles | Metrics
    Study on Transition of Land Use Function and Ecosystem Service Value Based on the Conception of Production, Living and Ecological Space: A Case Study of the Fuzhou New Area
    DAI Wen-yuan, JIANG Fang-qi, HUANG Wan-li, LIAO Li-hong, JIANG Kun
    2018, 33 (12):  2098-2109.  doi: 10.31497/zrzyxb.20171197
    Abstract ( )   HTML ( )   PDF (6049KB) ( )   Save
    Transition of land use function and transformation of ecosystem services value provide basis for management and layout of production-living-ecological space in rapid urbanization areas. Based on three periods of Landsat ETM+/OLI remote sensing data of the Fuzhou New Area in 2000, 2009 and 2015 and land use classification system based on the leading function of “production-living-ecological space”, the characteristics of land use function transition and the spatio-temporal evolution of ecosystem service value in 15 years in the Fuzhou New Area were quantitatively studied. The results showed that: 1) The area of living and production space in the Fuzhou New Area expanded 11 224.63 hm2 in 15 years, with a growth rate of 82.31%, while the area of ecological and production space increased firstly and then followed by a decrease, with a total increase of 19.94%. The growth of the living space resulted from the occupation of the ecological space and production space, while the growth of ecological and production space is derived from the wetland and the sea area. 2) The ecosystem service value in Fuzhou New Area decreased by 21.69% in 15 years. The decrease of ecological space was the largest in amount, which was 682.28 million yuan. The decline of living production space was the largest in percentage in the 15 years, which was 92.10%. 3)Regional ecosystem service value reflected two opposite trends at the same time: improvement and deterioration. The main reasons for the decline of the ecosystem service value in the study area stemmed from the encroachments of living-production space in ecological space and production-ecological space from the living space whose contribution rates were 38.60% and 18.77%, respectively. 4) Measures should be taken to promote the coordinated layout scheme of “production-living-ecological space”, strengthen the ecological forest, Minjiang estuary and coastline in the protected areas, and steadily promote the optimization of living space infrastructure in the core areas and townships in the new area, intensively use production space and increase the output benefit. The research results will provide a scientific basis for coordinated land resources development and eco-environmental protection in the coastal rapid urbanization area.
    References | Related Articles | Metrics
    Effects of Tending on Stand Growth and Spatial Structure in Picea asperata Plantation
    FENG Yi-ming, CAO Xiu-wen, LIU Jin-qian, LI Bo, QI Ri, ZHAO Yang, CHEN Xue-long, LI Yi
    2018, 33 (12):  2110-2123.  doi: 10.31497/zrzyxb.20171301
    Abstract ( )   HTML ( )   PDF (1127KB) ( )   Save
    Forest tending is the basic requirement of scientific, efficient and sustainable management of forests. Taking two experimental areas of young and middle-aged Picea asperata plantation in Shatan National Forest Park, Gansu as the research objectives, the spatial structure, non-spatial structure of forest after five different adjustment measures and a no-optimizing (control) treatment were investigated and analyzed continuously in six years. The five kinds of tending methods were forsook, sanitary cutting, mechanical thinning (cut one row every one other row, cut one row every two other rows), and ecological thinning measures, hereinafter referred as FJ, WF, JF1, JF2 and SF. In the young forest, we found that forest tending significantly influenced the average DBH of the stand, height, diameter, individual volume and volume growth. After six years, the average stand DBHs tended by FJ , WF, JF1 , JF2 and SF were -0.3, 0.2, 2.1, 4.5 and 2.3 cm higher than that of control trees, respectively. The volume of individual tree tended by FJ , WF, JF1, JF2 , and SF tending measures were 1.2, 1.1, 4.0, 7.8 and 10.2 times higher than that of control trees, and volume growth were 1.5, 1.4, 1.8, 8.1 and 10.4 times higher than that of control trees. In the middle-aged forest, we found that forest tending significantly increased not only the average stand DBH but also the stand volume growth. After six years, the average stand DBHs of trees tended by FJ, WF, JF1, JF2 , and SF were 0.2, 0.3, 2.8, 2.6 and 1.6 cm higher than that of control trees, respectively. The stand volume of trees tended by FJ, WF, JF2 and SF were 2.1, 2.6, 11.7 and 18.2 times higher than that of control trees, respectively, except the stand volume of trees tended by JF1 which increased -16.8 m3/hm2. In addition, the tending measures of SF was the most favorable one in improving the stand volume. The forest tending did not significantly increased the degree of spatial separation, which had less influence on the size differentiation of trees, but it significantly decreased the forest uniform angle index. It was near normal distribution that the left side of the frequency is greater than the right side, and the spatial distribution of stand was adjusted to random distribution or uniform distribution. The results of our comprehensive analysis show that the most effective forest tending measures for Picea asperata plantation is SF and JF2 in young forests whose stand density was 4 500-4 800 trees per hectare, but only SF can used in middle-aged forests whose stand density was 1 630-2 151 trees per hectare. However, to achieve an increase in stand DBH and total volume growth, the stand density should be 3 200-3 500 trees per hectare in young forests and around 1 500 trees per hectare in middle-aged forests.
    References | Related Articles | Metrics
    Resource Evaluation
    Discussion on Different Driving Factors of Diversified Construction Land Expansion in Rapid Urbanization Area: A Case Study of Yiwu City
    XIONG Chang-sheng, TAN Rong, YUE Wen-ze
    2018, 33 (12):  2124-2135.  doi: 10.31497/zrzyxb.20170948
    Abstract ( )   HTML ( )   PDF (3655KB) ( )   Save
    Revealing the distribution pattern of urban expansion and detecting the determinants of urban expansion can help to understand the mechanism of urban development and forecast the urban change, which will be meaningful for decision-making on city management. Many outstanding researches have focused on this topic and made massive contribution to the knowledge system of it. However, a research gap is still left behind for deeper understanding. Most of previous literatures regarded the urban expansion as the sprawl of all construction lands and ignored the diversity of construction lands, such as residential land and industrial land, therefore, the researches exploring the determinants of urban expansion might neglect the fact that different types of construction lands could be driven by different determinants, e.g., commercial lands prefer to locate at the surrounding of CBD while industrial lands are more likely to locate far away from CBD. Hence, to fill in this gap, this paper aims to figure out the different determinants of diversified construction lands under the background of urban expansion. In detail, the multinomial Logistic regression model was applied in Yiwu, a city in Zhejiang Province, to detect the difference between determinants of commercial-residential land and industrial land expansion during 2006-2014. These two types of construction lands accounted for a big proportion of urban expansion during this period in Yiwu. The result illustrated that the urban expansion in Yiwu is the result of interaction of multiple factors, including natural environment, human activities and policies. A significant difference existed between the determinants of commercial-residential lands and industrial land expansion, which is mainly reflected in the following three aspects: 1) they are driven by different determinants, e.g., land price has positive effect on the expansion of commercial-residential lands while has no significant relationship with industrial land expansion; 2) they are driven by opposite effect of the same determinants, e.g., distance to the CBD and distance to industrial parks both have opposite influences on these two types of land expansion; 3) they are driven by different degree of effect of the same determinants, e.g., the commercial-residential land expansion is more sensitive to the amount of neighboring urban built-up area, while the industrial land expansion is more likely to change with the amount of available neighboring developing area. Furthermore, due to the different determinants, the development of Yiwu city exhibited a characteristic of the separation of production and residence. Given this situation, it's necessary to enhance the road network construction so as to improve the connection between industrial production and residential living in Yiwu. This study revealed the difference between the determinants of commercial-residential land expansion and industrial land expansion under the background of urban sprawl, which give a further understanding of the mechanism of urban expansion and can help to provide scientific basis and direct reference for urban planning and urban management in the future.
    References | Related Articles | Metrics
    Rainstorm Characteristics and Its Relationship with Waterlogging Disaster in Shanghai during 2007-2016
    LI Hai-hong, WU Ji-dong
    2018, 33 (12):  2136-2148.  doi: 10.31497/zrzyxb.20180559
    Abstract ( )   HTML ( )   PDF (8895KB) ( )   Save
    Based on hourly precipitation data of 30 automatic weather stations in Shanghai during 2007-2016 and 110 alert phone calls from the Shanghai Emergency Linkage Platform, the distribution characteristics of rainstorm and waterlogging disaster in Shanghai in the past ten years were analyzed using the methods of statistics and GIS, and the relationship between disastrous rainstorm processes and waterlogging disaster were further studied. The results indicate that: 1) The spatial distribution of rainstorm days in Shanghai reflected the urban rain-island effect, and extreme hourly rainfall intensity was relatively prone to occur on the eastern coast where the vapor is abundant and in the central urban districts where the level of urbanization is high. 2) The annual variation of waterlogging disasters was big. The monthly distribution curve of waterlogging disasters showed a single peak, and the daily distribution was double peaks. Waterlogging disasters are densely concentrated in the central urban region and the centers of districts, which reflecting the spatial characteristics of the disaster bearing body. 3) The rainstorm process had a significant contribution to the waterlogging disasters. The number of waterlogging disasters was significantly related to the process rainfall, maximum hourly rainfall and maximum hourly rainfall intensity and was less related to the duration and the affected stations. 4) When the maximum hourly rainfall was equal to the process rainfall and the process rainfall was less than 60 mm, the number of waterlogging disasters was less than 20, however, the waterlogging disasters increased dramatically as the process rainfall increased gradually, especially when the process rainfall exceeded 100 mm. This study on the relationship between rainstorm characteristics and waterlogging disaster is of great significance for disaster forecasting, warning and service.
    References | Related Articles | Metrics
    The Seasonal Spatiotemporal Variation of the Temperature Mutation and Warming Hiatus over northern China during 1951-2014
    LIANG Long-teng, MA Long, LIU Ting-xi, SUN Bo-lin, ZHOU Ying, LIU Yang
    2018, 33 (12):  2149-2166.  doi: 10.31497/zrzyxb.20171187
    Abstract ( )   HTML ( )   PDF (15903KB) ( )   Save
    Over the past hundred years, remarkable changes occurred around global climate. Two significant characteristics of climate changes are temperature mutation and warming hiatus, which led to a variety of extreme climate events of all scales, such as in the north of China. Therefore, revealing the features and rules of temperature mutation and warming hiatus in northern China could provide some basis to deeply understand climate changes, prevent and mitigate disasters as well as improve ecological environment in northern China and in the whole world. Based on the seasonal (monthly) average minimum temperature, average temperature and average maximum temperature data at 357 meteorological stations in northern China and surrounding areas during 1951-2014, this paper analyzes the spatio-temporal variation of three types of seasonal temperature (the average minimum temperature, average temperature and average maximum temperature) mutation and warming hiatus over northern China by using Mann-Kendall test, slide t test and other methods. The results indicate: according to the average minimum temperature, average temperature and average maximum temperature, the abrupt change of temperature and warming hiatus became late and the cycle from abrupt change to warming hiatus became short as the latitude reduces. In spring and winter, the temperature mutation and warming hiatus in the Northeast China were the earliest (1970s-1980s, 1993-2002), in North China were the second and in the Northwest China were the latest (1990s-2000s, 1996-2010). While in summer and autumn, the temperature mutation and warming hiatus in North China were the earliest, in Northeast China were the second and in Northwest China were the latest (1990s-2010s). There was little distinction among areas in warming hiatus year. Meteorological stations with no mutation and no hiatus were centralized in mountainous regions, high-latitude areas and southern part of North China Plain where the surrounding areas were relatively late in mutation and warming hiatus. The mutations and warming hiatus of same kinds of temperature became late in the order of winter (1981-1990), spring, autumn and summer (1994-2008) and winter (1995-2008), autumn, summer and spring (1998-2010). The cycle from temperature mutated to warming hiatus became short in the sequence of winter, spring, autumn and summer, during which the average minimum temperature period was the longest in winter (9-24 a). The average minimum temperature mutated earliest in spring, summer and winter, which occurred during 1972-1999, 1987-1999 and 1971-2000, the average temperature was the second to mutate, while the average maximum temperature was the latest to mutate which occurred during 1975-2008, 1994-2008, 1972-2006. However, in autumn, the mutation of the average temperature was the earliest (1982-2001), the mutation of the lowest average temperature was the second, and the mutation of the highest average temperature was the latest (1987-2001). The warming hiatus of the average minimum temperature, average temperature and average maximum temperature in spring and summer became late successively, which were during 1994-2008, 1997-2008 and 1997-2010, respectively, while the sequence was opposite in autumn and winter. The lengths of periods from temperature mutation to warming hiatus in each season in order were that of the average minimum temperature (9-18 a), that of the average temperature and that of the average maximum temperature (5-12 a). In particular, the three kinds of temperatures all mutated earliest in the southern of North China in summer, which is inconsistent with the rule in the whole area that the mutation became late as latitude decreases, and the temperature at most stations in this area did not mutate, which is also inconsistent with the general rule in the whole area.
    References | Related Articles | Metrics
    Research on the Basic Farmland Distribution in Mountainous Areas Based on Ecological Harmony and Construction Suitability
    HOU Xian-hui, ZHAO Min-juan, LIU Jing-ming, ZHANG Dao-jun
    2018, 33 (12):  2167-2182.  doi: 10.31497/zrzyxb.20171112
    Abstract ( )   HTML ( )   PDF (8881KB) ( )   Save
    With the background of ecological civilization construction, the basic farmland layout which gives consideration to both ecological environment protection and farmland protection is not only an urgent task to delimit the permanent basic farmland but also the main content to construct land use development pattern. At present, the research of basic farmland layout still treat cultivated land as resources but neglect the rationality of cultivated land's generation and existence in regional ecological system, and thus it caused aggravated ecological and environmental problems. This paper carried out research from both ecological harmony and construction suitability point of views. The ecological harmony of basic farmland was diagnosed with the minimum resistance model from two perspectives of biodiversity conservation and soil and water conservation, and the comprehensive quality of farmland and soil environment which can reflect the construction suitability of basic farmland was evaluated based on the comprehensive evaluation model with multi-factor and Nemerow Pollution Index respectively. Finally, reasonable distribution index was used to ensure the types of basic farmland distribution. The results indicated that: 1) The regions which have low ecological harmony mainly distribute in the town of Ansha, Huainan and Gongshan. It will cause soil loss, water shortages and degradation of bio-diversity if the basic farmland locates in these areas. The high ecological harmony regions which are suitable for basic farmland mainly distribute in the town of Xiaotao, Xiyang and Gongchuan. 2) There are 15 030.23 hm2 of cultivated land suitable for basic farmland, accounting for 85.48% of the total area of cultivated land. 3) The cultivated land can be divided into four types by Jenks Method. The priority type and basic protection type have better ecological harmony and construction suitability in which basic farmland can be distributed directly. The moderate layout type need to be screened based on the results of comprehensive land management and landscape planning, while the withdrawing type is not suitable for basic farm land. The conclusion of this article is that the layout method not only guarantees the internal requirement of basic farmland protection system to protect the high quality cultivated land, but also emphasizes the interaction between cultivated land and region ecological system and promote the coordinated development of mountain land use and ecological environment. The result of this paper can provide reference for decision-making in comprehensive land management, high standard basic farmland construction and ecological environment planning.
    References | Related Articles | Metrics
    Comprehensive Performance Evaluation of High Standard Farmland Construction in Mountainous Counties—A Case Study in Dianjiang, Chongqing
    MA Xue-ying, SHAO Jing-an, CAO Fei
    2018, 33 (12):  2183-2199.  doi: 10.31497/zrzyxb.20171185
    Abstract ( )   HTML ( )   PDF (20061KB) ( )   Save
    Evaluating the comprehensive performance of high standard farmland construction project has important significance in the implementation of high standard farmland planning and government decision-making. On the bases of particle projection pursuit model (PP) optimized with swarm optimization (PSO) algorithm, investigation data, maps and statistic data of land use were used to build the index system for comprehensive performance evaluation of high standard farmland construction project in Dianjiang County, Chongqing. The results showed that: 1) Compared with the situation before the construction of high standard farmland, the contiguous degree of cultivated land increased by 13.56%, which indicated the improvement of the agricultural land flat condition. After the construction of high standard farmland, arable land showed significant discreteness, and the rate of terraced field increased significantly. The road accessibility also increased by 25%, which showed the improvement of the agricultural production conditions. Spatial dispersion slightly increased and agglomeration effect appeared after the project implementation. Road hardening rate were high in the middle and low at two sides of the area after high standards farmland construction. Irrigation guarantee rate and ditch density were improved apparently after high standards farmland construction, and the improved area was closely related to the industrial structure and terrain conditions in the south. The vegetation coverage rate of farmland ecological environment kept remarkably discrete during the whole process of the project. The thickness of effective soil layer increased obviously, and its spatial distribution is quite related with road accessibility. There existed big dispersion in the improvement of multiple subjects' satisfaction that both individual satisfaction and corporation satisfaction were high in southern crane platform areas after the implementation. The spatial distribution of newly increased annual income was evenly distributed after the high standards farmland construction. 2) As for the comprehensive effect evaluation, the comprehensive effect of Class Ⅰ production area, accounting for 53.26% of the area, was the best where the multiple subjects' satisfaction was promoted, the agricultural condition, the farmland ecological environment and the agricultural land flat condition were all improved. The overall comprehensive effect of Class Ⅱ area, taking 37.62% of the area, was the second where the projection values of the four subgoals matched the effect and comprehensive results will be significant after the completion of the project. The comprehensive effect of Class Ⅲ area, taking 9.12% of the area, was relatively poor where the projection values of the four subsystems were relatively low. Comprehensive evaluation of high standard farmland construction should take unique regional characteristics into consideration, formulate scientific and reasonable evaluation plan, and orderly perform differential evaluation.
    References | Related Articles | Metrics
    Study on the Evolution of Construction Land Slope Spectrum in Shenzhen during 2000-2015
    PENG Qiu-zhi, TANG Ling, CHEN Jie, WU Ya-ling, CHEN Xiang-ze
    2018, 33 (12):  2200-2212.  doi: 10.31497/zrzyxb.20171159
    Abstract ( )   HTML ( )   PDF (9523KB) ( )   Save
    The horizontal expansion process of construction land often occurs with vertical climbing process in the rapid urbanization area which constrained by topographic factor. Slope spectrum is a useful tool that can help people understand the spatial-temporal characteristics and evolution laws of the vertical climbing process of construction land. A lot of useful knowledge needs to be mined from the morphological characteristics of slope spectrum curve to guide planning makers to make more scientific land use planning. In this paper, taking Shenzhen and its 10 districts as examples, SRTM DEM data and Landsat TM/OLI images in four periods from 2000 to 2015 were used to build the background land surface slope spectrum and construction land slope spectrum. Aiming to study the morphological characteristics and evolution laws of the construction land slope spectrum, some qualitative empirical knowledge and a series of quantitative indices based on slope spectrum theory were defined, such as steepness of slope spectrum, evenness of slope spectrum, and forward cumulative critical value of slope spectrum. The results show that: 1) The overall expansion rate of construction land in Shenzhen was decreasing and tended to be stagnant from 2000 to 2015. The main spatial pattern of construction land change is characterized by the coexistence of climbing and reclamation and is dominated by stable climbing process. 2) Each municipal district shows different characteristics of construction land slope spectrum which can be summarized as four types: climbing dominated type such as Longhua District, reclamation dominated type such as Nanshan District, climbing and reclamation mixed type such as Yantian District, and stable type such as Futian District. 3) The steepness of slope spectrum is below 0.2, the evenness of slope spectrum is between 0.4 and 0.8, the main upper limit slope of construction land is between 4° and 14°, and the extreme upper limit slope of construction land is between 7° and 20°. In other words, for Shenzhen and its districts, construction land tend to congregate in flat region, and the climbing degree of construction land is not serious. Besides, all the quantitative indices of slope spectrum in the southern municipal districts are larger than those in the north. This research suggests that Shenzhen will still face the pressure of construction land climbing in the near future. It is very necessary and urgent to set scientific and strict standards of upper limit slope for construction land climbing, and it is also important to enforce these standards strictly.
    References | Related Articles | Metrics
    Research on Carbon Emission Peak in Yangtze River Economic Zone with Steady Economic Growth: Based on Data of Global Night-time Light
    CHEN Zhi-jian, LIU Yue-mei, LIU Xiao, KONG Fan-bin
    2018, 33 (12):  2213-2222.  doi: 10.31497/zrzyxb.20171145
    Abstract ( )   HTML ( )   PDF (3660KB) ( )   Save
    The time and level of carbon emission peak will affect the development space of regions and have a far-reaching impact on the coordinated development in the Yangtze River Economic Zone (YREZ). This is also a problem to which we need to attach great importance when coping with climate change and regional management. Night-time light has become a typical remote sensing data used to describe the intensity of economic activities. This paper builds the measurement model of night-time light and GDP in the YREZ. According to the estimated results, the fitting precision is high and the GDP can be well explained by the night-time light by the model. This paper estimates and calibrates the GDP in the YREZ with the data of global night-time light from 1995 to 2013, and then predicts the GDP in the YREZ from 2014 to 2050 under the situation of steady economic growth. Three simulation scenarios based on decay rate of carbon intensity are designed to explore the time and level of carbon peak in the YREZ. The result shows that there is no carbon peak in Jiangsu and Jiangxi with the same drop index of carbon intensity as in the “12th Five-Year Plan” period, and carbon peak in other regions will appear before 2050. Furthermore, Yunnan will reach the carbon peak in 2025 which is 6.54×107 t. In addition, in the scenario of the drop index of carbon intensity as same as in the “13th Five-Year Plan” period there is no carbon peak in Jiangsu, and the carbon peak in Anhui and Jiangxi will appear after 2040. In the same scenario, the carbon peak in Chongqing, Sichuan and Guizhou will appear around 2031. Furthermore, Yunnan will reach the carbon peak in 2023. In addition, the above two simulated scenarios both show that the time of carbon emissions peak in upstream area of Yangtze River is earlier than that in the midstream area. It should be pointed out that the decay rate of carbon intensity in Chongqing and Sichuan region reaches 4.30% and that in Guizhou and Yunnan region reaches 3.90%. Moreover, the carbon peak in Chongqing, Sichuan, Guizhou and Yunnan are 8.17×107, 1.36×108, 1.16×108 and 6.32×107 t, respectively. Therefore, the speed of economic growth is an important factor that affects the carbon peak. In the scenario with the goal of achieving carbon peak in 2030 in the YREZ, there are significant regional differences in the decay rate of carbon intensity. For example, the decay rate of carbon intensity in Yunnan is 2.58% and in Jiangxi is 7.53%. Therefore, regional imbalance in economic development should be taken into full consideration as well as the coordination of carbon intensity and economic growth rate when it comes to formulate carbon reduction plan. Meanwhile, emission reduction policy of achieving carbon peak by regions and by phases should be formulated, which is conducive to the target of achieving carbon peak with steady economic growth.
    References | Related Articles | Metrics
    Effects of Different Tillage Methods on Soil Organic Carbon Pool Management Index and Its Composition in Weibei Highland
    ZHANG Xia, DU Hao-hui, WANG Xu-dong, LI Jun
    2018, 33 (12):  2223-2237.  doi: 10.31497/zrzyxb.20171206
    Abstract ( )   HTML ( )   PDF (1918KB) ( )   Save
    To investigate the effect of different tillage methods on soil carbon pool management index (CPMI), carbon sequestration rate (CSE), wheat yield and straw returning apparent humification coefficient, a nine-year (2007-2016) field experiment with six tillage measures under straw returning condition in Wei Highland was conducted. The tillage measures included three single continuous tillages (no-tillage (NN), subsoiling (SS) and conventional tillage (CC)), and three rotational tillages (no-tillage-subsoiling (NS), subsoiling-conventional tillage (SC) and conventional tillage-no-tillage (CN)). The results showed that, compared with the conventional tillage, the measure of NN increased carbon sequestration rate, soil organic carbon content (SOC) and its oxidative components (EOC), and carbon pool management index in surface soil (0 to 10 cm) while decreased SOC and EOC, but increased the stability coefficient of organic carbon (KOS) in soil layer deeper than 10 cm. The measure of SS increased the SOC, EOC content, CSE, CPMI in the surface soil layer and 35-50 cm soil layer, improved the EOC/SOC values in the soil layers of 0-10 cm and 35-50 cm, and increased KOS in 10-20 cm soil layer. Rotational tillages increased the SOC, EOC content and CSE in each soil layer, and increased the EOC/SOC value in the soil layers of 0-10 cm and 35-50 cm, NS and CN rotational tillages increased CPMI in each soil layer. Compared with the conventional tillage, the yield of wheat grain and the dry mass of wheat straw were increased in the treatment of SS, NN and rotational tillage, and the maximum increment was found to be in the treatment of NS which was 14.3% for grain yield and 12.9% for straw dry mass, respectively. After the nine-year straw returning, the apparent humification coefficient of returning straw increased in the SS, NN and rotational tillage, and the apparent humification coefficient of NS treatment was significantly higher than that of the conventional tillage.
    References | Related Articles | Metrics
    A Tentative Study of “Cloudy and Rainy Area Effect” of the δ18O in the Precipitation of Typhoon “Dujuan”
    XU Tao, CAI Jian-rong, SUN Xiao-shuang, CUI Meng-yue, LEI Guo-liang, JIANG Xiu-yang
    2018, 33 (12):  2238-2248.  doi: 10.31497/zrzyxb.20171244
    Abstract ( )   HTML ( )   PDF (5113KB) ( )   Save
    Typhoon precipitation is conspicuous in southeastern China, but little is known about the characteristics of the stable isotopes in these heavy rainfall events. It is thus highly needed to study the variation and controlling factors of the stable isotopes in extreme precipitation events. According to the meteorological data and stable isotope compositions of precipitation in Taipei and Fuzhou, the No. 21 Typhoon “Dujuan” led to landfall twice in Yilan County, Taiwan Province and Putian City, Fujian Province respectively, from September 28th to 29th, 2015. This paper analyzed the characteristic of stable isotopes in the precipitation of Typhoon “Dujuan” and the influence factors. During the period of Typhoon “Dujuan”, the δ18O varied from -3.4‰ to -15.0‰ with a fluctuation range of 11.6‰. The stable isotope compositions in the precipitation at the front and back in these two places are relative positive, and the average values vary from -4‰ to -6‰. The stable isotope composition of precipitation in the central area of these two places are most negative, and the average values are -12.4‰ and -13.2‰, respectively. The stable isotope compositions of front-end and back-end precipitation in two places are relative positive and the water vapor is obviously affected by “evaporation effect”. The stable isotope composition of middle-end precipitation is mainly influenced by “cloudy and rainy area effect”, which has the most negative values. In the sharp rise process of the airflow in cloudy and rainy area of Typhoon, water vapor rapidly condensed and fell in supersaturated environment, and the effect of kinetic fractionation is small, so the δ18O is most negative. Characteristics of δ18O, deuterium excess and simulated vapor transport trajectories suggest that the water vapor source of precipitation with Typhoon “Dujuan” is the western Pacific Ocean.
    References | Related Articles | Metrics
Share: