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    Resource Utilization and Management
  • Resource Utilization and Management
    Lü Xiao, HUANG Xian-jin, ZHONG Tai-yang, ZHANG Quan-jing
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    The purpose of this paper is to determine whether land-use planning has controlled construction land expansion based on the perspective compositing consistency and effectiveness. The conceptual model was built up and used in a case study of Tongzhou in Jiangsu. The GIS spatial analysis method and a Logistic model were used to evaluate the consistency of construction land expansion before and after the land-use planning, and the effectiveness of landuse planning, respectively. The results showed that: 1) Based on the perspective of consistency, the controlling effects of space scale and space structure show that, the construction land expansion controlling effects of Tongzhou are poorer in the last round of general land-use planning. In contrast, the controlling effects of newly-increased urban industrial and mining land are better than land use at the rural residential land. 2) Based on the perspective of effectiveness, landuse planning has an significant impact on construction land expansion; the reserved area of construction of land-use planning has played an obvious space guiding function in construction land expansion. But contrary to expectations, planning of basic farmland protection areas has not played a proper role in constraint. 3) Taken together, the consistency of land-use planning implementation was poor and the land-use planning in an incomplete ideal state has an effect just to a certain degree. 4) It is known by contrast, the driving action of space location variables for construction land expansion will be relatively stronger after the development to a certain stage. It means that cluster development may become inevitable and it is necessary to strengthen space controlling effects of land-use planning implementation. This model can evaluate the controlling effects of land-use planning on construction land expansion better; it can provide a reference for improving the planning implementation evaluation method of theory and technology.

  • Resource Ecology
  • Resource Ecology
    WANG Li-yan, XIAO Yi, RAO En-ming, JIANG Ling
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    As food production becomes unstable and the issue of food safety is increasingly outstanding, it is necessary to understand the spatial distribution characteristics of food provision service. In this study, we used "calories" which were standardized from food production according to the food-nutrition converting formula, to assess the spatial characteristics of food provision service and its impact factors. The results showed that: 1) In 2010, the total food production value was up to 11765.28×1012 kJ in China, and the food production capacity of southeast is stronger than that of northwest. 2) The capacity of food production varied in different geographical regions, that East China has the best food production function, followed by Central and Northeast China. Henan, Shandong and Heilongjiang were the three major food provision provinces. 3) Under the situation of cultivated land resources dwindling, technology elements play a more important role in improving the food production capacity of the ecosystem. Factors like sowing area, effective irrigated area, chemical fertilizer, agricultural machinery power, agricultural populations, and farm chemicals have significant positive correlation with food production capacity (P<0.01). Therefore, in order to improve China's food production capacity and realize the sustainable development of society and environment, the important ways are to take full advantage of natural resources and make more efforts to use scientific techniques.

  • Resource Ecology
    YANG Xin, CAI Yin-ying, ZHANG Xiao-yu, ZHANG An-lu
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    Farmland not only provides people with food and material, but plays an integral role in national food security, recreation, biodiversity conservation. The central government has adopted a series of severe policy and mechanism to protect farmland in China. However, due to the huge difference of the economic output of agricultural land and industrial land, the current non-equilibrium farmland protecting policy brings "wipeouts" and "windfalls" to the farmland protecting stakeholders without related compensations. Thus, effective design of farmland spatial eco-compensation has aroused the attention of domestic researchers and government policymakers. Based on their ecological account, this paper established a spatial compensation transfer Model to calculate the farmland spatial transfer eco-compensation among districts in Wuhan Metropolitan Area by combining the methods of ecological services value and ecological footprint/ capacity. The results are described as following: 1) The value of farmland ecological service in Wuhan Metropolitan Area achieved as much as 75.00×108 yuan in 2008, which is quite a huge non-market value that shouldn't be ignored. The district which has the largest value of ecological service is Qianjiang District (6.37×108 yuan), while the least is Jianghan District due to the fact that there is no farmland in this district. 2) For the Wuhan Metropolitan Area, the amounts of districts which are negative in their farmland ecological account is 24, which means there are 24 districts that should transfer farmland spatial eco-compensation to other districts. Among those 24 districts, Wuchang District should pay the largest amount of farmland ecocompensation to other districts (5967.92×104 yuan), with Tieshan District transferring the least (14.94×104 yuan); while the rest 24 districts should obtain farmland eco-compensation. District that should receive the largest amount of farmland spatial compensation is Huangpi District (238.91×104 yuan), with Yingshan County receiving the least (5.14×104 yuan). 3) The amounts of farmland spatial eco-compensation transfer among districts are much lower than their financial income, the proportion of farmland spatial transfer amounts to their financial income varies from 0.07% to 5.24%, so it is realistic to take the farmland spatial eco-compensation transfer measures. In order to protect and enhance the sustainable and variable ecological service supplied by the farmland ecosystem, a reasonable and feasible farmland spatial eco-compensation transfer amounts among different districts should be estimated. Based on ecological account, this paper provided an easy but reliable way to calculate the farmland eco-compensation and its spatial transfer in Wuhan Metropolitan Area by establishing a farmland spatial eco-compensation transfer model, which can also provide guidelines to the calculation of other ecosystem's spatial eco-compensation transfer at different levels.

  • Resource Economics
  • Resource Economics
    YANG Huai-yu, YANG Zheng-yong
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    It is very important to evaluate land use efficiency for land managers and policy makers. In this paper, through the portfolio model of land use, we evaluate the effect and efficiency of land use and management in reclaimed area of Lingang New City, Shanghai from 2003 to 2010, using two indicators of Sharpe index (θ) and economic return per unit of risk (δ). The result of the study shows that from 2003 to 2010, Sharpe index (θ) increased from 0.11 to 12.77 and economic return per unit of risk (δ) increased from 0.69 to 12.96, indicating that land use of reclaimed area of Lingang New City has a good effect. Analysis on the efficiency frontiers indicates that Sharpe index (θ) and economic return per unit of risk (δ) failed to achieve the optimal value from 2003 to 2010. The land use was under-utilization in 2003; the status of the land use in 2008 was between the optimal value of "economic return-risk" and the optimal value of "total return-risk" ; the intensity of land use in 2010 was too high. Because of the lack of data, it is difficult to estimate the optimal portfolio of the land use in the future.
  • Resource Economics
    DENG Yu
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    Spatial pattern and bid rent of land price is an important basis for organization of land use, configuration of traffic infrastructure, improvement of land policy, and promotion of land use efficiency. In this paper, the spatial pattern and bid rent of land price is investigated based on measurement of the comprehensive accessibility. This study finds that: 1) the spatial pattern of land price is significantly characterized by single center circles. Moreover, land price decreases with the decrease in time accessibility. 2) Commercial land price is dominant in the first circle, but it decays most quickly with the decrease of accessibility; the decay rates of comprehensive land and residential land are relatively lower; the price of industrial land has no significant correlation with the accessibility. 3) Within 0.75 h of time accessibility the price of commercial lands is significantly higher than that of other types of land; the inflection of residential land appears at the 1 h time accessibility. The 1 h isochron meets the locations of rail station and main transportation, which points out the farthest tolerable commuting distance of people. The price of industrial lands is related to the property of the industry and the land policies, and has no relation with time accessibility. Therefore, in order to build a cosmopolis, realize the integration of Beijing-Tianjin-Hebei, and relieve the pressure of ecological environment, the industries should be relocated in a larger spatial extent.
  • Resource Evaluation
  • Resource Evaluation
    GUAN Xu, JIN Xiao-bin, YANG Xu-hong, GUO Bei-bei, ZHOU Yin-kang
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    Farmland consolidation is the focus of land consolidation in China. As increasing the area of effective cultivated land and improving the quality and the scale of cultivated land are important orientations and goals of farmland consolidation, so it requires coordination between farmland consolidation and the quantity and quality of cultivated land to a certain degree. In order to find out this coordination both on space and time, based on the data of consolidation project from 2006 to 2012 by the Ministry of Land and Resources, combined with land use data and production of agricultural land classification and gradation, the paper first establishes consistency models and gravity center models by spatial analysis tools in ArcGIS at county level. Then the coordination of farmland consolidation and cultivated land resources is analyzed at national and provincial level. The results show that: 1) In terms of national level, 52.2% of farmland consolidation was arranged in the region of 14.4% of cultivated land during 2006 to 2012. It shows a poor coordination between farmland consolidation and the quantity of cultivated land resources. 2) When it comes to provincial level, the gravity centers of farmland consolida-tion are convergent to the gravity center of cultivated land in the majority of provinces. There is a good consistency between the arrangement of farmland consolidation and the distribution of cultivated land. 3) The proportion of farmland consolidation and cultivated land is relatively identical at each grade of cultivated land. The ratio of superior and inferior cultivated land increase gradually, while the higher grade shows a downward trend and the medium changes little. 4) We can easily find that the farmland consolidation gravity centers of each grade of cultivated land and the land gravity center are consistent in spatial distribution. The arrangement of farmland consolidation on superior and medium cultivated land becomes more and more balanced. The consolidation of higher cultivated land stresses to north and the consolidation gravity center of inferior cultivated land shows an annual difference. The above results reflect that the arrangement of farmland consolidation is unreasonable at national level. In some provinces, the current arrangement is not suitable to optimize sustainable development. It is necessary for the government to reduce the proportion of land development. Meanwhile, we can also find that the farmland consolidation becomes more and more balanced, and it also reflects a public welfare according to the increase of consolidation on inferior cultivated land. In the future, the guiding role of national land consolidation planning should be strengthened to standardize the provincial farmland consolidation project. We should take the opportunity to improve the quality of cultivated land of the whole country.

  • Resource Evaluation
    WANG Jin-liang, SHAO Jing-an, LI Yang-bing
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    The Geo-spectrum unit of land use change can unify "the map expressing the spatial cells" and "the spectrum expressing the starting point and the process of phenomena" , and can establish the integrated space-property-process information. Supported by 3S technology, this paper built Geo-spectrum information of crop and forest land use change in the Three Gorges Reservoir Area at two stages (1990-2000, 2000-2010) based on TM/ETM images and auxiliary image interpretation, and also built Geo-spectrum of crop and forest land use change model which combined land use information of three periods (1990, 2000, 2010). Then the change trajectories, characteristics and laws of crop and forest land use in the Three Gorges Reservoir Ar-ea are discussed. The results showed that: 1) The interchange among crop land, forest land, and grass land, the crop land and forest land occupied by building land were the main ways of cropforest land use conversion throughout the 1990-2000 phases in the Three Gorges Reservoir Area. The change of crop land to building land (code 15)" , "grassland to forest land (code 32)" and "forest land to grassland (code 23)" were the most marked types in spatial differences, and the spatial isolation of them were low. 2) The isolation of Geo-spectrum unit of crop and forest land use change increased during 2000-2010, and the spatial scale of Geo-spectrum unit of crop and forest land use change further enlarged during 2000-2010. The most marked types were the change of "crop land to forest land (code 12)" and "crop land to building land (code 15)" . The second marked types were that of crop and forest land use flooded by water body (code 14 and 24). The area of this type enlarged. 3) The change in earlier stage and later stage were the main ways of crop and forest land use change in the Three Gorges Reservoir Area, so the transformation of crop and forest land use have obvious characteristics of stages.

  • Resource Evaluation
    WANG Yi-qiang, ZHAO Yuan
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    This article first analyzes the development of different types of natural gas flow zones, and then divides all the provinces into four flow types: non-flow zones, output centers, input centers and exchanging centers. Next, this article analyzes the concentration and diffusion characteristics, current spatial pattern and its evolution of source and terminal regions of natural gas resources flows. Conclusions are drawn as follows: 1) the numbers of no natural gas flow zones, one-way output zones, one-way input zones and two-way exchanging zones all stabilized during the Eleventh Five-Year Plan period. The number of output centers is small but the quantity of flow is large. The number of input centers is large and they are widely distributed. Generally speaking, it presents a significant characteristic of centralized output and dispersed input in geographic space. 2) Current situation of China's natural gas output source has a characteristic of random distribution. But the terminal regions of natural gas flows have strong positive spatial correlation, which presents a significant spatial agglomeration pattern. Shandong, Jiangsu, Zhejiang and Shanghai show a high-high agglomeration mode, but Yun-nan, Sichuan, Tibet, Qinghai and Gansu show a low-low agglomeration mode. 3) The spatial pattern changes of China's natural gas output zones have three different stages: was relatively stable during 2001-2003; moved northwestward, expanded in space, and widely dispersed during 2004-2006; transferred to the east, spatially contracted, and significantly concentrated during 2007-2011. The spatial pattern changes of China's natural gas input zones have two different stages: expanded in east-west direction while contracted in north-south direction during 2001-2005; and relatively stable in spatial structure, and had obvious trend of intensification during 2006-2011.
    To summarize the flows of natural gas resources in China, the following conclusions can be drawn. 1) Regional natural gas resources abundance and the development sequence are major factors of the forming of the source regions of natural gas resources in China. 2) The spatial pattern of the terminal regions changes with the evolution of natural gas consumption pattern. 3) Based on current spatial pattern of source and terminal regions of natural gas resources and current status of natural gas pipeline construction, it is recommended that the planning and construction of natural gas main network should extend to the southeast coastal areas of China. Meanwhile, to meet the demand of natural gas consumption in these areas in a timely manner, more work needs to be done, such as layout and optimization of shore stations and pipeline infrastructures for imported liquefied natural gas.
    Studying on the spatial pattern of natural gas resources, this paper takes provincial regions as homogeneous space nodes. In theory, this study should take natural gas pools as the sources of resources flows and take the locations of consumer terminals, such as natural gas power plants, as the terminals. In addition, as the import of liquefied natural gas from overseas is gradually growing, the disturbance of liquefied natural gas on natural gas resources flow in China is gradually increasing. However, this paper does not bring oversea liquefied natural gas into the system of natural gas resources. Therefore, future research should further strengthen the analysis on the influence of international liquefied natural gas market on natural gas resources in China.

  • Resource Evaluation
    ZHANG Tao, LI Bao-lin, HE Yuan-qing, DU Jian-kuo, NIU He-wen, XIN Hui-juan
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    Precipitation measurement is always an important problem in mountainous areas. Because of multiple factors such as atmospheric circulation, topography, and land-sea positions, precipitation shows strong spatial-temporal heterogeneity, especially in mountainous areas. Meanwhile, although traditional rain gauges and rainfall measuring radar on the ground can obtain the precipitation information precisely, the distribution density and range of the observation sites are the main limitations. Tropical Rainfall Measuring Mission (TRMM) data may fill the gaps. The Hengduan Mountains, which is located in the southeast of Qinghai-Tibet plateau, has been chosen as the study area in this article. There are 38 weather stations interspersing in this region, and the recorded monthly precipitations from 1998 to 2012 have been used as the truth values, hence the TRMM 3B43 V7 data are verified during the same period. After that, a calibration method based on linear regression of monthly TRMM 3B43 data of each subregion has been carried out by using ISODATA clustering and maximum likelihood method. Finally, the spatial and temporal distribution features of precipitation in Hengduan Mountains are investigated. Results show that TRMM 3B43 data have significant correlation with perticipations, while have low precision at almost half of the sites. After correction, the precision is improved greatly. The number of the stations whose biases (compared with the rain gauges) are more than 10% decreased from 16 (42.1%) to 7 (18.4%), that is, 81.6% of the stations have the biases below 10%, and only 3 stations have TRMM biases ≥20%, which is acceptable in the study area. The precipitation decreases gradually from southeast to northwest, which shows the same tendency as the East Asian Monsoon in Hengduan Mountains. Precipitation in the study area is decreasing during 1998-2012, mainly in the southern and mid-western regions. Precipitation in summer displays the most decrease, that in autumn ranks the second, while there are no significant changes in spring and winter. Precipitation in most of the Hengduan Mountains shows positive correlation with the East Asian Summer Monsoon Index, while displays negative correlation with the East Asian Winter Monsoon Index. The East Asian Summer Monsoon Index in this area is continuously shrinking in the last 15 years, which is consistent with the decreasing trend of precipitation indicated by this article.

  • Resource Evaluation
    LIN Hou-bo, YOU Qing-long, JIAO Yang, MIN Jin-zhong
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    Based on high resolution data of the daily precipitation over the Tibetan Plateau (hereafter TP) from 1961 to 2010, the spatial and temporal characteristics of precipitation over the TP are studied. According to relatively heavy rain, rainy, relatively little rain, little rain and drought area, the whole TP is divided into eight subareas, which represent the amounts of precipitation in the region. The trend and distribution of annual and seasonal precipitation over the TP are analyzed and discussed during the studied period. The results show that the distribution of the average annual precipitation over the TP is uneven and has spatial differences, decreasing from the southeastern to northwestern TP. At the same time, the precipitation has seasonal differences, with largest/smallest amount in summer/winter, followed by spring and autumn. The distribution of precipitation in summer is like the annual average precipitation. In other seasons, the precipitation is generally concentrated in the southern, southeast and southwest TP. The trends to the east and west of 102°E are quite different in the TP. The trend of seasonal average precipitation is obvious, dominated by region and time. Regions with larger average precipitation also have larger magnitudes of increase. Each subarea has increased precipitation in each season, except the large area in the eastern TP having decreasing trend in summer, and regions around Lhasa having reduced trends in winter.

  • Resource Evaluation
    YANG Jin-hu, SUN Lan-dong, LIN Jing-jing, YANG Jian-ling
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    Using the re-analyzed monthly mean NCAR/NCEP data,daily summer (from May to August) precipitation data of 156 stations from 1961 to 2012 in the east part of Northwestern China and 74 Circulation Indices from CMA, and using precipitation anomaly percentage of summer, the evolution features of the drought and flood sharp turns in recent half century are studied by defining the drought-flood sharp turn index, and the circulation characteristics of drought-flood sharp turn phenomenon over the southeast part of Northwestern China are analyzed. Additionally, a prediction model of drought-flood sharp turn phenomenon is established. The result showed that the annual differences of drought and flood sharp turns in summer are small over the southeast part of Northwestern China in recent half century. By comparison, the frequencies of drought-flood sharp turn events were more before 1992, and it were less after 1992. In drought period of drought-turn-flood years, Arctic polar vortex leans to east and is weak, the Ural ridge leans to be strong, East Asian trough leans to west and be deep, also the westerlies at the middle and high latitudes leans to be strong and prevents cold air to move southward. In addition, there is no unusual moisture transport belt, which cause that there is no abnormal cold air and warm-moist airstream to affect the southeast part of Northwestern China. And the vertical field displays downdraft. So, there is less rainfall in drought periods. In flood period of drought-turn-flood years, the Ural blocking leans to be strong, the Mongolia low pressure is deeper, the Subtropical high pressure leans to west and be strong, the southeast part of Northwestern China is located at the periphery of the subtropical high pressure and the bottom of Mongolia low pressure. There is enough warm and moisture air flow from southwest, so the rainfall tend to be more. Also, the westerlies at the middle and high latitudes tends weak which helps the cold air move southward. In addition, the anomaly moisture conveyor belt coming from the Pacific Ocean may reach this region, and the vertical field displays updraft, so the rainfall leans to be more. In flood-turn-drought years things are opposite. Ensemble forecasting model of drought-flood sharp turn is established with the pre-atmospheric circulation index which is significantly associated with the drought-flood sharp turn index. Additionally, ensemble forecasting model is examined by using of the recent ten years of data, and we found that the model has the ability to predicate the drought-flood sharp turn phenomena in summer in the southeast region of Northwest China, thus it provides a reference for short-term climate prediction.
  • Resource Evaluation
    LIAO Shu-fen, WANG Xin, XIE Zi-chu, LIU Shi-yin, LIN Jian, JIANG Zong-li
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    Characteristics of glacial lake variation were analyzed in the views of temporal and spatial evolution based on four phases of glacier lake inventories of 1970s, 1990, 2000 and 2010 respectively. The glacier lake variations are characterized by a general trend of "weak decrease in the number and marked increase in the area" in Chinese Himalayas during the past 40 years. The number of glacier lakes decreased with a rate of 0.3%, and the area of glacier lakes increased with a rate of 53.1%±11.5%. The interdecadal differences are obvious, and 2000 is a turning point in the number of glacier lakes (the number of glacier lakes decreased before around the year of 2000, while increased after that), but the area of glacial lakes kept continuous growth in last 40 years. It was found that the growth rate of glacier lakes was much faster at western watersheds than that in the eastern watersheds and decreased with a linear rate of 2.4%/(°) from west to east. In addition, the glacial lake areas are widely expanding at different elevations. Therein, the annual net glacier lakes growth rate of 76.7% watersheds present a " single-peak " growth model at different elevations with 100 m bandwidth, and the others present "double-peak" or even " multi-peak " expanding models, which reflects the complexity of glacier lakes evolution at different elevations and the vertical differentiation of the climatic change. The positive correlation relationship is remarkable between the normalized glacier areas and the normalized glacier lake areas, and it appeared a trend of "normalized glacier areas decrease and normalized glacial lake areas increase" in different watersheds of Chinese Himalayas during the past 40 years.

  • Resource Evaluation
    WANG Yan-jun, WANG Sui-ji, SU Teng
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    Water resource is now a serious problem around the world due to the impact of climate change and increasing human activities. There are serious concerns about the impacts of climate change on water resources.Water resource problem is particularly prominent in semi-arid and arid regions since the water resources and primarily runoff in these regions are highly sensitive to climate change; and a small change of climate variables may result in significant variation of hydrological cycle and subsequently change the regional water resource. With a channel of 2309 km and a basin of 5.57×105 km2, the Songhua River is located in the northeast of China where the latitude is high and the climate is cold. Natural runoff as the main source of surface water plays an important role in agricultural irrigation, socio-economic development, hydropower generation, wetland recharge and local eco-environmental conservation in the ba-sin. However, the runoff in the whole river basin has experienced dramatic change in the last decades. It is necessary to study the trend of the runoff change and to quantify the influencing factors of the runoff change on different spatial scales. Based on annually observed hydrological data at six gauge stations on the Songhua River mainstream and annual precipitation at 62 meteorological station in and around the Songhua river basin, the changes of annual runoff and the contributions of the major influencing factors to them during the period 1955-2010 were analyzed. First, the cumulative anomaly and sequential cluster were used to detect the abrupt changes of each runoff series. Three inflexion years were detected that divided the entire time period into four periods (increasing-decreasing-increasing-decreasing) for each gauge station. Without considering the effect of evapotranspiration, the slope change ratio of cumulative quantity (SCRCQ) was adopted to estimate the impacts of precipitation and human activities. The result shows that the contribution of precipitation was 26%-35%, 0.1%-10% and 25%-43%, respectively, while that of human activities was 65%-74%, 90%-99.9% and 57%-75% respectively for the different periods compared with the baseline period. It is obvious that the human activities are the most important factor to runoff change. While the impact of human activities on runoff change is still increasing in most basins of china, that of the 4th period in the Songhua River basin was less than the 3th periods. However, the effect of human impacts was still greater than that of precipitation. Considering the severe stress of water resource, anthropogenic impact on runoff changes should be given more attention in future.

  • Resource Evaluation
    HUANG Hui-ping, CAO Ming-ming, SONG Jin-xi, HAN Yu-ping, CHEN Shan-shan
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    According to daily meteorological data of 608 weather stations in China from 1957 to 2012, the thesis analyzes the temporal and spatial changes and trends of the potential evapotranspiration (ET0) in China using Penman-Monteith formula. Based on ArcGIS, SPSS and principal component analysis, this paper discusses the distribution characteristics and influencing factors of ET0. The results show that in the 56 years the average annual ET0 is between 616 and 2128 mm with the average of 1104 mm, and the highest value is 3.45 times of the lowest. In the Hexi Corridor, South of the Five Ridges, Hainan Island and the coastal area of southern China, ET0 is comparatively larger; however, in the northeast region of Heilongjiang, Sichuan basin and the east region of the southwestern area, ET0 is smaller. The ET0 of ten hydrological regions indicates decline trend, and the rate of the Northwest Rivers region is -12.22 mm/10 a. The rate of Haihe, Liaohe, Huaihe, Yangtze region is -9.15, -9.11, -8.02, -5.44 mm/10 a respectively. In Huanghe, Southeast, Southwest, Songhua regions, the decline rate is comparatively smaller. The interannual fluctuation in Huanghe and Southwest Rivers region is sever. The peak and minimum value appears in different month in ten regions. The maximum appears in July in Northwest Rivers, Huanghe, Southeast Rivers, Yangtze and Zhujiang regions, in May in the Southwest, Liaohe, Songhua, Haihe regions, while in June in Huaihe regions. Among influencing factors of ET0, the first principal component is the thermodynamic factor, the second principal component is the moisture and radiation factor, the third component is constitute of the geographic and aerodynamic factors, and the elevation factor composes the fourth.

  • Resource Evaluation
    YU Zhi-kang, SUN Gen-nian, LUO Zheng-wen, FENG Qing
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    Global warming lead to universally high temperature in summer. Traditional avoid summer heat in the mountains has been unable to meet the public demand for cool climate environment. This paper, focusing on summer tourism in high-latitude of China, selected 212 cities long-term climate observation data from 1980 to 2010, quantitatively evaluated summer climate comfort degree of cities to the north latitude of 40°N by THI, WCI, and ICL. Conclusions are as follows: 1) From the spatial distribution, vast northeastern plains are suitable for summer tourism. In mountainous region of northern Inner Mongolia and Xinjiang, the regions appropriate for summer tourism are small. From time series, the most comfortable time being June with average index is 7.62, next is August with average index of 7.28, July has the relatively poor climate comfort and its average degree is 6.81. 2) The longest avoiding summer heat period is more than 60 days, which includes Heilongjiang, Jilin, Liaoning and Xinjiang Altay region. Second is northern Hebei and central Inner Mongolia, Xinjiang Yili region, the summer heat avoiding period is 30 to 45 days. However, in western Inner Mongolia, Xinjiang Tianshan valley the period is less than 30 days. Among a year, the longest comfortable month is August with average days adding to 25.1, next is July with average days about 20.2, the shortest climate comfortable time is June with average days about 19.9. 3) The high-latitude summer tourism comprehensive regionalization in China is divided into six types. From the type of statistics, the more suitable summer tourism regions are mainly distributed in the high latitudes of centraleast China, and the most competitive provinces are the three northeastern provinces of China. This research provides a certain reference for the choice of summer tourist destination and the formulation of summer tourism development strategy.

  • Resource Research Method
  • Resource Research Method
    LI Jie, HU Jin-ming, ZHANG Hong, LUO Huai-xiu, JIA Hai-feng, ZHANG Kou-qiang
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    The present study took the Napahai ungauged subalpine wetlands as an example and built an empirical correlation model between the climatic factor and the hydrological factor based on the time lag effect of basin runoff. This model took advantages of the climatic factor to simulate the fluctuation of hydrological factor. Forty-eight scenes of Landsat Thematic Mapper/ Enhanced Thematic Mapper Plus (TM/ETM+) images from 1990 to 2011 were catalogued to extract the open water areas (OWA) in the wetlands. Then the accumulated daily precipitation (ADP) levels at different time steps were generated by statistically computing the daily rainfall data in the study area. Through regression analysis between OWA and ADP at different time steps, optimal accumulated daily precipitation (OADP) was screened out and the empirical correlation model of OADP-OWA was also obtained. And then with the help of empirical equation between open water storage (OWS)-OWA in Napahai wetlands, the correlation model of OWS-OADP was established. The simulated results showed that the hydro-regime of Napahai kept stable in the dry season (November to April) and fluctuated sharply in the rainy season (May to October) on the inter-annual time scale. On the intra-annual time scale, the average monthly OWS raised in July, got maximum of 8.66×106 m3 in September, then rapidly declined in October, and kept stable of 0.95×106 m3 from November to July in the next year. September was the most urgent month for protecting the surrounding villages from flooding. This is basically consistent with the data from field surveys and remote sensing image interpretation information. It is suggested that the above model could simulate the fluctuation trends of the OWS in Napahai wetlands and could effectively reduce the influence of data deficiency on the quantitative simulation of hydrological regime in wetlands. The above model provides a new vision for hydrological studies of ungauged subalpine wetlands, and offers the basic data and method for preventing the flood in this area.

  • Resource Research Method
    CHENG Qian, CHEN Jin-feng
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    Under the complex coastal land environment, how to improve the extraction accuracy of land cover information by remote sensing is a key problem. This paper, taking southern coastal land of Hangzhou Bay as the study area, using most newly launched GF-1 satellite and Resources satellite No.3 remote sensing images extract the land cover information by the object-oriented classification method compared with maximum likelihood method. The results show that comprising with the maximum likelihood method, the object oriented method with GF-1 image are more suitable for extraction of coastal land information. It not only considers the object spectral, spatial and texture features, but also makes full use of the rich texture and spatial information of GF-1 image, which has better recognition ability for various land types, distribution of fuzzy coastal land boundary of mixed pixels, thus getting higher classification accuracy of 90.4% and Kappa coefficient of 0.8767. The choice of segmentation scale is an important influence on high precision image classification, and the results show that image segmentation optimal scales of GF-1 2 m and 8 m images are 63% and 65%, and the optimal segmentation scale of Resources No.3 images is 66%. Comprising with resources satellite No.3, GF-1 image can reflect more advantages in land cover information extraction in the aspects of ground vegetation and water.