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  • 2012 Volume 27 Issue 6
    Published: 20 June 2012
      

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  • WANG Cheng-jun, FEI Xi-min, XU Xiu-ying
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    The purpose of this paper is to perform an investigative analysis of the influence and functional mechanism of rural labor force transfer on woodland element circulation between rural households. This paper conducts a theoretical analysis of the functional mechanism underlying the influence of rural labor force transfer on woodland circulation between rural households. Empirical test is also conducted based on econometric calculation and research statistics from rural households of two counties/cities in Zhejiang Province. The result shows the transfer of rural surplus labor can promote the restructuring of woodland between rural households. It can, to some extent, promote the optimization of woodland and labor. This paper also finds that the woodland production in China has now a certain degree of scale economy, and woodland is still partially responsible for the livelihood of rural households. The result will provide indication for subsequent researcher and the policy-making in the woodland area.
  • ZHAO Yun-tai, HUANG Xian-jin, ZHONG Tai-yang, ZHANG Xiao-ling, PENG Jia-wen, DU Guan-yin, XIAO Li
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    The purpose of this study is to analyze whether the implementation of land supervision is effective in land marketization and assess the extent of the effects. Based on province-level panel data from 2003 to 2008, methods of fixed-effects model and random-effects model were employed to estimate the equations. The test on the models suggests that the fixed-effects model is more appropriate than random-effects model. The effects of land supervision on land marketization were evaluated on the basis of the estimation of the fixed-effects model. The results show that: 1) Land supervision has played a positive role in land marketization in China from 2007 to 2009. The growth of every percentage point in special land supervision coverage brought about 0.14% growth in land marketization degree. The growth of every percentage point in regular land supervision coverage brought about 1.12% growth in land marketization degree. 2) Land marketization degree in China respectively increased 2.06%, 0.19% and 0.55% in 2007, 2008 and 2009 because of the implementation of special land supervision; land marketization degree respectively increased 5.01% and 12.47% in 2008 and 2009 because of the implementation of regular land supervision. 3) On the whole, the implementation of land supervision has promoted the degree of land marketization in China, and accordingly land marketization degree respectively increased 2.04%, 5.21% and 13.02% in 2007, 2008 and 2009. The implementation of land supervision has effectively promoted the development of land marketization. Land supervision on land use and management of local government should be further strengthened, especially in implementing special land supervision on the act of excessive and illegal intervention in land supply of local government, in order to reduce the existence of gray land market and promote the healthy and stable development of land market.
  • ZHAO Jian-an, JIN Qian-zhi, WEI Dan-qing
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    This paper analyses the energy predication and consumption patterns since the 21st century in China, especially in the energy consumption of the energy-intensive industries. Meanwhile, it compares the gap between China’s per unit product energy consumption of the relatively energy-intensive industries with the international advanced level. To the gap and major problems, it probes into China’s potential of the energy-intensive industries in energy-saving and carbon emission reduction. Through energy-saving and carbon dioxide emissions of the energy-intensive industries, in the national total targets that reduce 40% to 45% of carbon dioxide of per unit GDP in 2020, it probes into the contribution rate and the contribution scale of the energy saving industrial technology of the relatively energy-intensive industries. Through technological progress of the coal, the iron and steel, the non-ferrous metals, the building materials, the petrochemical, the chemical, the coal mining, the oil and gas mining and other major energy-intensive industries, it is forecasted that the energy-saving potential of industrial technology would realize 51560×104-52000×104 tec and would reduce carbon dioxide by a total size of 125800×104-126880×104 t. Carbon dioxide emissions in the entire unit of GDP would decrease by 40% to 45% of the national target in 2020, the energy saving and carbon emission of industrial technology accounts for the contribution rate of 15.5%-16.5%, and will not be able to assume primary responsibility for achieving national target. In addition, China’s industrial technology for energy saving potential and carbon emission reduction for further expansion, the future path of the main energy saving was discussed. Included the steady progress of the CCS projects(Carbon Capture and Storage)in the energy-intensive industries, backward technology and equipment and new material to speed up the elimination industry to achieve economies of scale enterprise development, strong industry association to promote industrial parks and guide the development of circular economy, strengthen the establishment of cleaner production organization and promote comprehensive utilization of resources.
  • YU Guo-qiang, ZHANG Xia, ZHANG Mao-sheng, PEI Liang
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    Mechanism of gravitational erosion in the slope-gully system and the root reinforcement reduction mechanism of the Loess Plateau was explored with the aid of the finite difference software, Flac3D, while numerical simulation of stress field and displacement field and plastic yielded zone with and without vegetation, and the reduction mechanism of root reinforcement was clarified. Results show that the displacement in the upper part of the slope-gully system appears mainly in the form of "settlement", and the displacement in the lower part appears mainly in the form of "shear", gully head traceability areas are most susceptible to gravitational erosion. The shear plastic zone is mainly distributed in most area of slope and gully slope, and the tension plastic zone is mainly distributed in tops and slopes of barren hills. As vegetation roots system reinforcement, the soil body stress of slope surface was improved, the extent of stress concentration and surface displacement were reduced effectively. The horizontal displacement and vertical displacement were reduced by 15% and 2.5% respectively. The volume of plastic yielded zone was also reduced, the volume of shear plastic zone and tension plastic zone were reduced by 11.48% and 83.99% respectively. The degree of damage of gravitational erosion was mitigated. However, the main failure model in the slope-gully system is still shear failure model. This study will provide a new method for understanding of vegetation root regulation on gravitational erosion.
  • L? Ming-quan, WANG Ji-jun, XIA Zi-lan, CHEN Zhi-xue
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    The payments for soil and water conservation environmental services are of great importance to soil and water conservation. The payments amount is a core issue of setting up payments for environmental services (PES) scheme. In this paper, Dongbeigou Watershed in the upstream area of the Panjiakou Reservoir was selected to study PES amount related to soil and water conservation, on the basis of land use in 1990 and 2009, soil, vegetation, DEM and peasant household survey data. The Revised Universal Soil Loss Equation (RUSLE) based on GIS was used to calculate the reduction of soil loss between 1990 and 2009 because of taking precaution measures against soil loss. The environmental economics approaches (nonmarket valuation methods) was applied in calculating downstream benefit from Dongbeigou Watershed providing soil and water conservation services, and Dongbeigou Watershed’s cost and benefit in providing soil conservation services. A payment amount for soil and water conservation environmental services model was set up based on previous calculation. The results indicated that the soil loss amount decreased by 6.49×104t·a-1 from 1990 to 2009. The watershed inhabitants providing soil conservation services lost 24.48×104 yuan/a from losing developing opportunities and gained 44.21×104 yuan/a from reducing land and fertility losses. Downstream water users receiving soil and water conservation services benefited 84.88×104 yuan/a from losing siltation and eutrophication of Panjiakou Reservoir. The compensation standard was from 24.48×104 yuan (222.55 yuan per person) to 46.90×104 yuan(426.36 yuan per person).
  • LIU Pu-xing, ZHANG Ke-xin, HUO Hua-li, PAN Jing-hu
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    Populus euphratica Oliv. has a decisive function in protecting fragile ecosystem balance in the middle and lower reaches of the Shule River Basin. It is important to comprehend characteristics and their causes of the spatial variations of soil water and salt content under Populus euphratica Oliv. in order to protect and renew Populus euphratica Oliv. for sustainable development of the oasis of the study area. Based on 720 soil samples of the 8 sites, we studied characteristics and their causes of the spatial variations of the soil water and salt content under the natural Populus euphratica Oliv. forests in the middle and lower reaches of the Shule River Basin by using methods of interpolation analysis of geostatistics and statistics. The results indicated that the soil water content was increased with the depth, while the soil salt content was decreased with the depth. The change was sharp from 0 cm to 80 cm, slow from 80 cm to 120 cm. And there were an obvious spatial variations of the decreasing soil water content and the increasing soil salt content from the middle reaches to the lower reaches of the Shule River Basin. Ranges of their variation coefficients were between moderate and intense, and the deeper the smaller. Though the variation coefficients of the soil water and salt content were obviously different in all layers in the middle to the lower reaches of the Shule River Basin, ranges of their variation coefficients were between both moderate and intense, and the deeper, the smaller. Both natural and human factors result in the evident spatial variations of the soil water and salt content in the study area.
  • DUAN Jin, KANG Mu-yi, JIANG Yuan
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    In this paper, through a case study conducted in cities involved in Dongjiang River Basin, we improved the ecological footprint model by adding freshwater resource account and pollution account and by adjusting the yield factors using actual average land productivity method. The ecological footprints of eight cities, i.e., Ganzhou, Meizhou, Heyuan, Shaoguan, Huizhou, Guangzhou, Dongguan and Shenzhen in the Basin in 2008 were evaluated using our revised ecological footprint model. The results showed that: 1) The ecological footprint and the ecological capacity of each city were sizably different from the other seven cities within the Basin. This reflects the differences both in natural resources endowment and in socio-economic development stage among the eight cities within the basin. The summed ecological footprint per capita increased spatially from the upstream to midstream and to downstream except for Huizhou and Shenzhen cities. While the available total per capita ecological capacity of cropland, forestland, pastureland, built-up land, fishing land and fossil-energy land decreased spatially from the upstream to midstream and to downstream. 2) As the per capita GDP and/or the urbanized population ratio increased, the spatial variation of the per capita ecological footprint increased first and then turned to decrease, showing a similar trend that EKC (environmental Kuznets curve) once expressed. 3) The total ecological footprint of all eight cities within the Basin exceeded the corresponding ecological capacity except for the freshwater resource, and thus there existed a global ecological deficit within the Basin. This indicates all the eight cities within the Basin have to import, more or less, natural products, resources and energy from outside regions at present, to sustain the normal development according to their current consumption standard and production conditions.
  • CAI Tai-yi, HUANG Hui-juan, HUANG Yao-wei, LU Wen-tao, JIA Zhi-kuan, YANG Bao-ping
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    A field experiment (2007-2010) was conducted at the Heyang Dryland Farming Experimental Station in Shaanxi Province of China to determine the effects of straw mulch rates on soil labile organic matter (LOC), carbon management index (CMI) and spring maize (Zea mays L.) yield. Maize straw at rates of 0 (CK), 4500 (S1), 9000 (S2) and 13500 kg/hm2(S3) was placed on field plots. The results indicated that soil organic carbon (TOC) content of S1, S2 and S3 treatments increased by 5.08%, 14.12% and 28.03%, respectively, compared with the CK at 0-20 cm soil layer; the LOC content increased by 19.20%, 44.02% and 23.50%, respectively; the CMI increased by 20.94%, 46.86% and 50.21%, respectively. Spring maize yield was found significantly (P<0.05) related to the LOC and CMI, while showed no significant correlations with the TOC. It was concluded that the LOC and CMI could reflect more rapidly and objectively the effects of different rates of straw mulch on soil carbon pool and maize yields more than TOC for the Weibei Dry Highland in China, besides, the treatment with 9000 kg/hm2 of straw mulch is preferable。
  • MA Ning, WANG Nai-ang, WANG Peng-long, SUN Yan-meng, DONG Chun-yu
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    Based on the daily data from 1960 to 2009 of 14 meteorological stations in Heihe River Basin and the surrounding areas, spatial and temporal distributions of the reference evapotranspiration in the Heihe River Basin were analyzed after calculation with the Penman-Monteith method recommended by FAO. Nondimensional relative sensitivity coefficients of reference evapotranspiration to climate elements of three representative stations in different regions were calculated to research the dominant factor of ET0’s change combined with the relative change of the climate element. The results showed that obvious regional difference of annual and seasonal ET0 in the Heihe River Basin and the former is estimated to be about 568-700 mm in the upper course, 800-900 mm in the Hexi corridor plain and over 1000 mm in the lower course. The ET0 of summer is the most in a year, followed by spring, autumn and winter is the least. In general, the annual and seasonal ET0 all decreased in past the 50 years, but also with regional difference, which increased slightly in the upper course and decreased in middle and lower course. The relative humidity is the most sensitive variable to annual ET0 in Tuole and Gaotai which belong to the upper and middle course, however, wind speed is the most sensitive variable in Ejina which belongs to the lower course. The seasonal and monthly sensitivity of climate elements in the three sites have a little difference. Wind speed is the dominant factor causing change of ET0, however, the relative humidity and sunshine duration contributed little.
  • LU Zhi-hua, XIA Zi-qiang, YU Lan-lan, WANG Jing-cai
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    In order to illustrate and analyze temporal and spatial variation of characteristics of precipitation in Songhua River Basin, the precipitation data were interpolated by Kriging interpolation method. The Mann-Kendall test was applied to examine the trend of precipitation. The concentration degree and period of annual precipitation were used to analyze the annual distribution of precipitation. The results show that ∶1) In recent 52 years (1958—2009) the annual precipitation shows an indistinctive negative trend. The annual precipitation decreases from eastern part to western part, and most of the basin area show an indistinctive negative trend. 2) The annual precipitation distribution is uneven, occurs mainly from May to September, with June to August being most abundant. The flood-season (from June to September) precipitation occupies 77.65% of the annual precipitation and shows a weak negative trend throughout the basin. 3) The concentration degree of annual precipitation is very high, averaging 0.682, and the concentration degree of southeastern part is smaller than that of northwestern part. The concentration period of annual precipitation is from 181.90° to 187.68°, the annual precipitation is concentrated from 20, July to 26, July, the concentration period of northern part is longer than that of southern part. The concentration degree of annual precipitation shows an indistinctive decreasing trend,while the concentration period of annual precipitation shows a significant decreasing trend.
  • JING Ya-ping, ZHANG Xin, LUO Yan
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    Urban water demand system is always nonlinear and stochastic, although combination model based on Grey Model and BP Neural Network has strength both on single variable forecasting and nonlinear problem, its weight coefficient calculating is uncertain and would affect forecasting result. Therefore, a combination model based on Grey Model and BP Neural Network and amended by Markov chain is set up to forecast Qinghai eight cities’water demand. The water consumption of Qinghai from 1980 to 2009 is used to verify this amended combination model and forecast eight cities’water demand in 2010, 2015 and 2020. The forecasting result shows that the combination model based on Grey Model and BP Neural Network and amended by Markov chain has smaller deviation and higher forecasting precision accuracy.
  • LIU Mei, XU Xin-yi, WANG Hong-rui, WANG Feng
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    Based on an overview of the concept and calculation method of virtual water and water footprint, water footprint and related indexes including water scarcity, water dependence, water self-sufficiency and water footprint intensity for each district of Hebei Province for the period 1995-2008 are calculated, then, time series of water footprint and water footprint intensity is analyzed. Furthermore, spatial classification is made by system cluster analysis of water footprint and related indexes. Moreover, according to virtual water trade balance and the comparison of water footprint and GDP growth, a spatial-temporal change of water footprint is further discussed. The results show that water footprint and water footprint intensity take on an upward trend and a downward trend respectively, and there are spatial variations in water consumption pattern, water use efficiency, water scarcity, water self-sufficiency and externalization of water footprint of various districts in Hebei.
  • REN Yong-jian, LIU Min, YUAN Ye-chang, SUN Shan-lei, YANG Hong-qing, WANG kai
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    Based on boundary layer model CALMET coupled mesoscale model MM5, wind region of Hubei Province was simulated, which had been 1 km horizontal resolution and 150 m vertical resolution. Compared with wind towers, the correlation coefficients of simulated hourly wind speed in July and November were 0.59, 0.57. The annual wind speed error at 70 m by the numerical simulation was 7.21%, and the monthly average error was respectively 6.62%-7.30%. Complicated by the underlying surface topography, 10 m height of the error was maximum, the simulation at 50 m was better than other heights. The hourly and monthly wind speed in different heights was well simulated. The distribution was that wind speed and wind power in the east was larger, and that the western contour was relatively messy and dense. The wind resource in winter and spring was greater than the fall and relatively poor in the western region. Although numerical simulation results had some errors, the simulated wind energy resource distribution was response to the regional climate and topographical features. The results can be used as the scientific basis for regional wind power development planning. In the process of selecting the wind farm sites, more wind towers need to be laid in regions with errors greater than the average level.
  • GENG Yuan-bo, SHI Jing-jing
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    The main purpose of partitioning soil respiration lies in accurately estimating the source and sink of carbon and soil carbon accumulation in grassland ecosystem and providing data for forecasting global climate change. The application of the stable Isotope 13C in the partitioning of grassland soil respiration was introduced in this paper. The applications are as follows: 1) Continuous labeling methods and pulse labeling methods of plants in grassland by 13CO2. Continuous labeling methods include bomb-14C labeling, 13C natural abundance labeling and FACE labeling, and pulse labeling methods include single pulse labeling and repeated pulse labeling. 2) The theory and method of calculation of separating soil respiration by stable isotope 13C. 3) Sampling and measuring of 13CO2 for soil respiration in grassland. They include a method of static closed chamber-Keeling Plot, a method of static closed chamber at equilibrium and a dynamic closed system with infrared gas analyzer (IRGA). 4) Means of improving Keeling-Plot accuracy for measuring carbon-isotopic composition of soil-respired carbon dioxide in static closed chambers.
  • WANG Chao-hui, LU Lin, XIA Qiao-yun
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    Events and mega events are significant tourism resources in the tourist destination, the mega event is an important means to improve the urban and its tourism economic development. The success of mega events, such as Beijing Olympic Games, Shanghai World Expo makes event tourism a focus of research domestic tourism field. Based on the concept and connotation of event and event tourism, the paper gives a review of mega events on their social, economic, political, cultural and environmental impacts, makes a comment on the research object, research perspective, research content, research method, research technology, research design etc., and puts forward the research focal point of the event tourism impact in the future, namely, improving the research content system, enriching the research technique, enhancing the empirical research and comparative research and so on.
  • HUA Chang-cheng, PENG Xing-qian, WU Ren-wei, SHAO Kun
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    The World Heritage Fujian Earth Buildings are located in China’s southeast coastal area where is frequently suffered from typhoon and severe weather, the annual amount of rainfall can be as much as 1600 mm.Whenever typhoon landed, the gustiness, gathering with the torrential rain, tends to erode and cause damages to these Earth Buildings, with that, the wind-driven rain’s erosion of the rammed earth wall has become the main form causing such damages. The accurate simulation of numerical wind tunnel can be completed by the adoption of methods of CFD numerical simulation and wind tunnel test, according to the analysis of the raindrops’ motion form and the rainfall characteristics under the effect of the wind-driven rain. Considering the various combinative conditions of the rain strength and wind speed based on the numerical wind field and rainfall model, followed by analyzing the erosion damage of the rammed earth wall caused by the weather beaten, in such way, whose inherent regularity can be revealed. The last step is to predict the annual range of average erosion damage which is from 0.4 mm to 2.6 mm by the calculation example based on the local meteorological statistical data. The result will provide the earth buildings’ maintenance reinforcement and exploitation with scientific basis, and provide the other rammed earth architecture with reference as well.