Table of Content

25 November 2012, Volume 31 Issue 11 Previous Issue    Next Issue

Original Articles

Magnetic Susceptibility of Glacial Deposits and the Impacting Factors in the Eastern Bordering Mountains of the Tibetan Plateau ZHANG Wei, LI Yuanyuan, FENG Ji, BI Weili, LIU Ge 2012, 31 (11):  1415-1425.  doi: 10.11820/dlkxjz.2012.11.001 Abstract ( )   PDF (1006KB) ( )   Save Magnetic susceptibility value of the continuous sediment samples from lakes, loess and paleosol, and deep sea are widely used as an alternative indicator of environmental change. However, magnetic susceptibility measurement has yet to be involved in the research on the non-continuous deposits that reflect the climate change in a specific time period, such as the glacial deposits. This paper reports the study of the magnetic susceptibility of eight typical profiles of glacial deposits in the eastern bordering mountains of the Tibetan Plateau and the comparison of the data to those of deposits from the lake, loess, deep sea and the surface soil. Based on the mass susceptibility and frequency susceptibility data, the magnetic susceptibility of the glacial deposits is characterized and the impacting factors are analyzed. The results are as follows. (1) The magnetic susceptibilitydata of the glacial deposits in the bordering mountains to the east of the Tibetan Plateau show a large amplitude of fluctuation between 3.01×10-8 m3·kg-1 and 1808.80×10-8 m3·kg-1, with a mean value of 147.84×10-8 m3·kg-1, while the frequency magnetic susceptibility values are small and fluctuated between 0 and 6.89%, with a mean value of 1.37%. (2) The temporal and spatial data of the magnetic susceptibility show different characteristics. In other words, the change of magnetic susceptibility in the different glacial stages of the same region is minimal, while the change of that in different regions of the same glacial stage is dramatic. (3) Parent rock lithology is the major factor affecting the magnetic susceptibility of the glacial deposits, while climate conditions havecomplex impact. References | Related Articles | Metrics

Reconstruction and Analysis on the Series of Winter-half-year Temperature Change during the Qing Dynasty in the Northern China Region YAN Junhui, GE Quansheng, ZHENG Jingyun 2012, 31 (11):  1426-1432.  doi: 10.11820/dlkxjz.2012.11.002 Abstract ( )   PDF (1634KB) ( )   Save Based on the records of irregular first and last frost dates from the historical documents during the Qing Dynasty, the winter-half-year temperatures in northern China region are reconstructed at a five-year resolution by applying a conversion function to the historical records obtained from examining the correlation between the changes of first and last frost dates and the changes of instrument-measured regional mean temperatures in more recent years. The characteristics of temperature changes in that period are analyzed. The results indicate that: (1) the climate in northern China region in the Qing Dynasty can be characterized as cold. The mean winter- half-year temperature of that time period in the region is 0.55℃ lower than that of the present time (1951-1980), with a 1.42℃ difference in the coldest five years (1656-1660). (2) The centennial scale climate variations show a“cold-warm-cold”pattern. The two cold periods appear around 1646-1700 and 1781-1910, when the winter-half-year temperature in northern China region is about 0.77℃ and 0.58℃ lower than that of the present days respectively. During the period of 1701-1780, the climate is relatively warm, but the winter- half-year temperature is still lower than that of the present days (by 0.36℃ difference). (3) At a higher time resolution, relatively small temperature fluctuations are observed within each cold and warm time period, with two“cold troughs”during the late Qing Dynasty (1781-1910). References | Related Articles | Metrics

Assessment and Intercomparison of Satellite-derived Start-of-Season (SOS) Measures in Eurasia for 1982-2006 LIU Lingling, LIU Liangyun, HU Yong 2012, 31 (11):  1433-1442.  doi: 10.11820/dlkxjz.2012.11.003 Abstract ( )   PDF (3970KB) ( )   Save Vegetation phenology is one of the most direct and sensitive indicators of seasonal and interanual variations of environmental conditions. Phenological changes reflect quick change of terrestrial ecosystems in response to climate change. Satellite remote-sensing techniques capture canopy reflectance and can be used for studies of vegetation phenology. In this study, satellite-derived Start of Season (SOS) dates are obtained from the GIMMS AVHRR NDVI dataset by different methods such as Dynamic Threshold method, Delayed Moving Average methods, Double Logistic analysis and Savitzky-Golay method. The derived SOS data are compared and analyzed for the ecoregions from China to Russia, and the Dynamic Threshold method is decided to be most suitable for Eurasia scale. Based on the analysis of the changes of vegetation phenology and the response of phenology to climate change from 1982 to 2006, it is concluded that the Dynamic Threshold method has high retrieval rate for the SOS dates in Eurasia, and the data show a stable trend along the latitudinal gradient. The retrieved SOS dates for boreal forests and tundra ecosystems are most stable in the long term, while in the vegetation areas of low latitudes the dates show higher variability. It is found that from 1982 to 2006, there is a trend of SOS dates becoming earlier for the majority of vegetation types, and the forest coverage areas show even stronger trend of SOS dates becoming earlier, with a change rate of 11.45-15.61 days/25 years, due to global warming. With the exception of the closed to open (>15%) shrubland (<5 m), for most other types of vegetation, there is a negative correlation between vegetation phenology and the average temperature of the month. In other words, for each one degree increase, there is 1.32-3.47 days decrease to SOS date in spring, which is consistent with global warming in recent years. References | Related Articles | Metrics

Comparative Analysis of Radiation and Energy Budget over Badain Jaran Desert on Clear and Cloudy Days in Summer LI Jiangang, AO Yinhuan, LI Zhaoguo 2012, 31 (11):  1443-1451.  doi: 10.11820/dlkxjz.2012.11.004 Abstract ( )   PDF (1366KB) ( )   Save Based on the study of land-atmosphere interactions in Badain Jaran desert in the summer of 2009, this paper presents a comparative analysis of diurnal variations of surface radiation, energy budget and soil temperature under different synoptic conditions. As shown in the results: (1) In Badain Jaran desert, global radiation, surface reflection radiation, surface long-wave radiation, effective radiation and net radiation are all greater on typical clear days than those on typical cloudy days. However, atmospheric long-wave radiation is greater on cloudy days. Under both weather conditions, daily integral value of net radiation is 1/3 of global radiation. (2) The distribution of day-time surface albedo on clear days takes a U shape with an average value of 0.32, while it is relatively flat on cloudy days with an average value of 0.29. (3) The sensible heat transfer is the major component of the surface energy budget. On clear days and cloudy days, Bowen ratio (the ratio of sensible heat to latent heat) is 4.55 and 1.16 respectively, and imbalance energy accounts for 20% and 30% of net energy respectively. (4) The effective energy is negative in day time and positive in night time on clear days, and is positive all the time on cloudy days. Turbulent energy is always positive. The average EBR (energy budget ratio) is 0.68 on clear days and 0.76 on cloudy days. (5) The diurnal variations of soil temperature decrease as the depth changes from 5 to 10 cm (Δ15.7℃ vs. Δ9.4℃). In 20~40 cm depth range, there is almost no diurnal variation. Under both weather conditions, soil heat flux shows greatest diurnal variations at 5 cm depth and very little at 20 cm depth. References | Related Articles | Metrics

Contributions of Local Moisture to Precipitations in Western China MA Qian, ZHANG Mingjun, WANG Shengjie, WANG Baolong, MA Xuening 2012, 31 (11):  1452-1459.  doi: 10.11820/dlkxjz.2012.11.005 Abstract ( )   PDF (1347KB) ( )   Save Based on stable isotope data of precipitations and lakes on the Tibetan Plateau and Tianshan-Altay areas, contributions of secondary evaporation and evaporative vapors to local precipitations are estimated. (1) The stable isotope data show that values of both δ18O and d-excess decreases from Hetian to Altay in summer monsoon (June to September), suggesting that in the area secondary evaporation has a greater effect in summer monsoon, while in Tibetan plateau area the stable isotope composition of hydrogen and oxygen increases along the water vapor trajectory in both summer monsoon and winter monsoon (October to May), contributed mainly by evaporative vapors from surface water bodies throughout the year. (2) The estimation of evaporation rate indicates that in Tianshan-Altay area the secondary evaporation happens at all times, and it has greater effect in summer monsoon, with rates from 13% to 20% and an average rate of 16.7%, and less effect in winter monsoon, with an average rate of 4.3%. (3) Using a vapor contribution rate model, contributions from moisture advection, evaporative vapors from surface water bodies, and transpiration from plants are calculated. Moisture advection generally contributes the biggest part, greater than 50%, while evaporative vapors contribute the smallest part, with an overall rate of 10%. Transpiration has a contribution rate in between. References | Related Articles | Metrics

13C Distribution Characteristics in Soil Profiles with the Impacts of Short-term Trees, Shrubs and Grass Replacement SHEN Yating, LU Guohui, HU Jundong, WANG Xuejun 2012, 31 (11):  1460-1466.  doi: 10.11820/dlkxjz.2012.11.006 Abstract ( )   PDF (783KB) ( )   Save To investigate the impact of short-term vegetation replacement on the distribution of organic carbon in soil and the mechanism of soil carbon cycle, five types of 0-110 cm mountain soil profiles with Quercus trees, shrubs, grass alterations are collected in Qujing, Yunnan Province, China. Each type of soil profile is divided into 6 layers. Stable carbon isotope ratios (δ13C values), total organic carbon (TOC) data and carbon density are measured. Results show that: (1) Changes of δ13C values after shrubs replaced by Quercus trees and grass are between 2.28‰ and 5.08‰. (2) Vegetation replacement has the greatest impact on 13C in SOM (soil organic matter) in the 0-10 cm soil layer. δ13C value in the soil layer of 30-50 cm depth is not sensitive to vegetation replacement, thus the leached layer can serve as a reference profile. (3) Short-term vegetation replacements (around 10 years) significantly influence δ13C values in the 0-30 cm soil layer. In the 0~50 cm soil layer, enrichment of 13C decreases as the depth increases. In addition, δ13C values have negative correlation with TOC. Change of atmospheric δ13C is not related to 13C enrichment in the 0-50 cm soil layer in the forest. (4) Soil organic carbon density in the 0-30 cm layer has changed by 2.30 kg/m2 and -1.00 kg/m2 in 10 years after replacement of shrub vegetation by oak plantings and herbaceous vegetation, respectively. (5) Planted oak forest has significant impact on short-term soil carbon diversity and storage increase. In 10 years after the change from shrubs to planted oaks, the annual carbon density has increased by 0.23 kg/m2. This paper concludes that δ13C can be used to distinguish C3 from C4, and even among the different C3 plant (such as arbor, shrubs and herbaceous) changes, hence widely used in the study of soil carbon storage turnover and carbon cycle. References | Related Articles | Metrics

Characteristics of Palaeoflood Slackwater Deposits of Yunxian County in the Upper Reaches of the Hanjiang River QIAO Jing, PANG Jiangli, HUANG Chunchang, ZHA Xiaochun, ZHAO Yanlei, ZHANG Yuzhu 2012, 31 (11):  1467-1474.  doi: 10.11820/dlkxjz.2012.11.007 Abstract ( )   PDF (3072KB) ( )   Save Palaeoflood slack water deposits (SWD) are very useful for hydrological reconstruction. Search for SWD has become a key step in the study of palaeoflood hydrology. Three types of sediments (palaeoflood SWD, paleosol and loess) are surveyed over the first level river terraces of the upper Hanjiang valley. Comprehensive analyses of macroscopic characteristics, grain-size distribution, magnetic susceptibility, loss-on-ignition, micromorphology, and major-elementcomposition are conducted in the laboratory. Results are shown as follows. (1) The color of palaeoflood slackwater deposits in the upper Hanjiang valley is gray-yellow (2.5 YR 7/2), with abrupt vertical changes and clear boundaries in the adjacent stratigraphies. (2) The palaeoflood SWD has coarse texture with silty fine sand, and is better sorted than other types of sediments, indicating that this type of sediment was formed by the suspended sediment load of floodwater. However, compared to palaeoflood SWD in the Weihe river valley, the latter is even better sorted because the majority of it is silty fine sand with even smaller grain size. (3) The magnetic susceptibility of the palaeoflood SWD is slightly higher than that of loess, but significantly lower than that of luvisols. (4) Loss-on-ignition of palaeoflood SWD is lower than that of loess and paleosol, which suggests that the palaeoflood SWD was fresh sediment without being affected by weathering and pedogenesis after deposition. (5) In micromorphology, the surface of the palaeoflood SWD is distributed with V-shaped pits, typically caused by physical collision and friction in running water. (6) The palaeoflood SWD is also different from paleosol and loess in major-element compositions and UCC (upper continental crust)-normalized patterns. These results are of great importance to the identification of the palaeoflood slackwater deposits in the upper Hanjiang valley and the reconstruction of the palaeoflood hydrological parameters. References | Related Articles | Metrics

The Regional Difference and Abrupt Events of Climatic Change in Tianshan Mountains during 1960-2010 ZHANG Zhengyong, LIU Lin, TANG Xiangling 2012, 31 (11):  1475-1484.  doi: 10.11820/dlkxjz.2012.11.008 Abstract ( )   PDF (1993KB) ( )   Save The data of monthly temperatures and precipitations during 1960-2010 from the 27 meteorological stations in the Tianshan Mountains, combined with DEM data, are used for the analysis of the temporal and spatial trends of climate changes, including some abrupt changes. As shown in the results: (1) annual average temperatures have shown a clear upward trend, with more dramatic temperature increases in the years of this century. The seasonal averages are changing in a similar fashion with the annual averages, with the winter averages showing the highest increases and the summer averages the lowest increases. The east side of the mountains shows the most striking trend of temperature increase, and temperature change on the north is more than that on the south. (2) Precipitationshave kept increasing since 1960’s, and the increase accelerates after 1980’s. Summer precipitations show the biggest increase, and spring precipitations show the smallest increase. The annual precipitation in the mountain regions are mainly contributed by summer and spring. In the spatial scale, the mountain climate shows a“two-center”pattern, with a center of“hot and dry”on the east, and a center of “warm and wet”on the northwest, and the contrast between the two is in the trend of expanding. (3) Abrupt changes in temperature and precipitation in the mountain regions are not evident. Spring and summer temperatures may have had abrupt changes in late 1990’s to early 2000’s, while abrupt changes to autumn and winter temperatures may have happened during 1990’s. There may be an abrupt change of annual temperature on the south and east side in 1982, on the north side roughly in 1990. An abrupt change of autumn precipitation occurs in the late 1980’s, but for other seasons there are not obvious abrupt changes. Annual precipitation has an abrupt change in the late 1980’s. References | Related Articles | Metrics

Review of Research on Rice Phenology Models ZHANG Shuai, TAO Fulu 2012, 31 (11):  1485-1491.  doi: 10.11820/dlkxjz.2012.11.009 Abstract ( )   PDF (452KB) ( )   Save Phenology, the study of biological events and how they are influenced by seasonal and interannual variations in climate change, is an important indicator of climate change, as more and more studies suggest that plant phenology goes through dramatic change in response to climate change. Thus an accurate phenology model is needed for us to accurately understand the mechanism of how crops respond to global climate change. Phenological sub-models are being widely used in the models such as ecosystem productivity models, land surface process models and crop simulation models, because phenology provides important data. A good phenology model improves the accuracy of the simulation of energy exchange between the earth and its atmosphere and the accuracy of carbon assessment. A robust phenology model has gradually become a critical tool for improving the accuracy of the simulation of the changes of crops in response to climate change, and the simulation of crop phenology in turn is an important part of crop model. Rice is one of the most important crops in the world and is the major food crop in China. This paper reviews research progress on rice phenology models abroad and at home, discusses the categories of the models and uses several models as examples. The current issues and future trends are suggested as well. This review can serve as a reference for research on rice phenology models and crop models. References | Related Articles | Metrics

Studies on the Transfer of the Right of Operation of Scenic Areas: A Review LIU Min 2012, 31 (11):  1492-1502.  doi: 10.11820/dlkxjz.2012.11.010 Abstract ( )   PDF (959KB) ( )   Save Transfer of the right of operation is a phenomenon of Chinese characteristics in the tourism industry. This paper provides a panoramic coverage and an objective review of the studies on the topic and proposes the focus for future studies. To make sure to meet the scientifically rigorous standard, this work uses systematic review methodologies. First a thorough search of the literature by key words is conducted, a number of papers are selected by certain screening criteria and repetitive papers excluded, and finally 143 papers published from 2002 to 2011 are chosen, including 120 Chinese articles, 22 master and doctoral dissertations and 1 conference publication. Five main conclusions are drawn from the analysis. (1) Main themes of the literature are the focus on the existent problems in the tourism practices with the attempts to investigate the causes and suggest alternatives, solutions and remedies, rather than the forward-looking studies. (2) Numbers of publications vary over time. Most papers were published from 2002 to 2006, with a peak number of 26 in 2006, and the number decreases afterwards. (3) Most works are rather shallow and the topics are scattered in different directions such as value assessment, benefits of transfer, models of transfer, executions of policies and regulations, government participations and policy recommendations, business entities, and reviews. (4) The studies are rather qualitative, lacking indepth investigations, and high percentage of the papers, up to 50%, focus on basic analysis. (5) Relatively speaking, among the scattered topics, value assessment, executions of policies and regulations, and benefits of transfer are the major ones with a good in-depth approach. Six topics should be investigated in the future: (1) the legal environment for the transfer of the right of operation of scenic areas; (2) the driving force and mechanism of transfer ability of the rights of operation; (3) method to assess the value of the right of operation and policy study; (4) relationships of the stakeholders and their interests in the transfer of the right of operation; (5) the micro- scale benefits of the transfer of the right of operation and case studies; (6) macro-scale studies of policy-making and regulation recommendations for the transfer of the right of operation. References | Related Articles | Metrics

Research Progresses of Surface Temperature Characteristic Change over Tibetan Plateau since 1960 SONG Ci, PEI Tao, ZHOU Chenghu 2012, 31 (11):  1503-1509.  doi: 10.11820/dlkxjz.2012.11.011 Abstract ( )   PDF (449KB) ( )   Save As the largest plateau in China and highest plateau on the earth, the Tibetan Plateau has a significant impact on global climate. This article reviews the progress of the study of the characteristics of the surface air temperature change over the Tibetan Plateau in the last 50 years and the causes for the change. The conclusions are as follows. (1) In the last 50 years, the surface air temperature over the Tibetan Plateau has clearly increased, through a cold period (mid-1960s to early 1980s) and a warm period (mid-1980s to present) with increasing fluctuations and the abrupt changes in the 1980s, showing an alternating“low and high”overall upward trend. (2) The upward trend of the lowest temperature and that of the highest temperatures are not in parallel. In other words, the lowest temperatures have increased more dramatically than the highest temperatures. In addition, the frequency and the intensity of the extreme events have also changed, with extreme low temperature events decreasing significantly and extreme high temperature events increasing slightly. (3) As the indices of the biological events, the accumulated temperatures and their time durations have increased as well. In spatial scale, the temperature in the Tibetan Plateau has shown an overall increase, with the change to a greater extent in the west than that in the east, and an opposite phase zonally. (4) Many factors affect the surface air temperature change over the Tibetan Plateau, such as sunspot cycle, various meteorological elements in the plateau and the atmospheric circulation. References | Related Articles | Metrics

Responses of Carbon Cycling Key Processes to Precipitation Changes in Arid and Semiarid Grassland Ecosystems: A review PENG Qin, QI Yuchun, DONG Yunshe, HE Yating, LIU Xinchao, SUN Liangjie, JIA Junqiang, JIN Zhao 2012, 31 (11):  1510-1518.  doi: 10.11820/dlkxjz.2012.11.012 Abstract ( )   PDF (412KB) ( )   Save Climate models predict that the amounts and the timing of precipitation will change in the future, both globally and regionally. Given the sensitivity of grassland to water availability in arid and semiarid areas, the variability of precipitation will undoubtedly influence the net primary production (NPP) and soil respiration (Rs), the two most key processes of carbon cycles in these ecosystems. And then, it can change the carbon budget of grassland. Thus, in order to better predict the function of carbon budget of grassland in future precipitation scenario, it is crucial to investigate the responses of the two key processes (NPP and Rs) to precipitation changes in arid and semiarid grassland ecosystems. This paper reviews research progress at home and abroad on how NPP and Rs respond to precipitation changes, points out the areas for improvement and discusses about the topics where more focus is needed in the future: (1) Study of the effects of precipitations intensity, frequency and interval on the responses of NPP, especially below ground NPP; (2) By better categorizing the components of soil respiration and studying the temporal and spatial variability of NPP and Rs, further explore the mechanism of their responses to the changing precipitation regimes; (3) Long term in-situ field research on the“lagged effects” of the responses of NPP and Rs to climate change. References | Related Articles | Metrics

Research Progress and Connotation of Cloud GIS LIN Degen, LIANG Qin’ou 2012, 31 (11):  1519-1528.  doi: 10.11820/dlkxjz.2012.11.013 Abstract ( )   PDF (1280KB) ( )   Save Cloud Computing is evolving as a platform of next generation. Its emergence promises to promote new developments in the Geographic Information System (GIS), which is closely related to computer sciences. This paper discusses the characteristics of Cloud Computing, the definition and the key technical and scientific issues of Cloud GIS. Cloud GIS is a new technology that utilizes the large-scale computing power of Cloud infrastructure to overcome the challenges of handling the massive spatial data in the GIS in several aspects, including multi-site distributed data storage, allocation of processing tasks, data query and retrieval, interoperability, virtualization, etc. By improving data processing and data management, Cloud GIS provides high-performance processing technologies to a variety of GIS services, such as data-intensive tasks and computing-intensive tasks. The essential connotations of Cloud GIS are the Cloud characteristics of spatial data and the Cloud Computing characteristics of data management. Cloud GIS goes beyond the“small professional community”of conventional GIS, brings the spatial information services and their values to the public, and in return makes a volutionary breakthrough for GIS itself and greatly expands the scale of the market for its applications. We introduce several CloudGIS platforms, and discuss advantages and disadvantages of the development of Cloud GIS. At the end is an overview of research progress on Cloud GIS in China in three aspects: the trend of technology models of Cloud GIS, the need for its applications, and the need for its education. References | Related Articles | Metrics

A Review of the Progresses of Avalanche Hazards Research WANG Shijin, REN Jiawen 2012, 31 (11):  1529-1536.  doi: 10.11820/dlkxjz.2012.11.014 Abstract ( )   PDF (500KB) ( )   Save With the global warming, the risk of cryospheric avalanche hazards has been gradually increasing, and receives a great deal of attention from the public. There has been significant progress in avalanche research in the fields such as: (1) mechanism of avalanche formation; (2) avalanche path; (3) dynamic simulation; (4) risk assessment and hazard zoning; (5) forecasting and prevention of avalanche hazards. Avalanche research has gone through the changes: (1) from field survey only to combination of field survey and remote sensing; (2) from qualitative and semi-quantitative to quantitative; (3) from empirical estimation to dynamic simulation; (4) from study of avalanche formation to avalanche risk assessment, adaptation and mitigation in the hazardous areas. However, previous studies put more focus on the mechanism of avalanche formation which involves weather, snowpack structure, terrain, etc., and relatively less focus on the vulnerability, exposure, adaptation measures in the hazardous areas. Only when the avalanche initiation areas and the hazardous areas are taken together under a systematic investigation, through early warning, prediction and forecasting, can the hazardous areas be protected against avalanche disaster and the loss of human life and property in the areas be prevented or minimized. References | Related Articles | Metrics

Integrated Innovation Systems for Climate Change Adaptation Technologies in North China Plain HAN Rongqing, PAN Tao, LIU Yujie, ZHANG Jiutian, WANG Wentao 2012, 31 (11):  1537-1545.  doi: 10.11820/dlkxjz.2012.11.015 Abstract ( )   PDF (788KB) ( )   Save Integrated technology innovation is a necessary approach to climate change adaptation. This paper, taking the North China Plain (NCP), one of the most important commodity grain producing regions, as a case, analyzes the impacts of climate change on the region’s agriculture, and puts forward several integrated innovation systems for climate change adaptation technologies for the agriculture in NCP, including: (1) single-objective system, (2) multi-objective system, (3) multi-agency system, (4) area-specific system. In examining the different scenarios for implementation of climate change adaptation, this paper discusses the uncertainty of climate change adaptation, differences in the need for the adaptation, and integrated innovation capability of the adaptation technologies. This paper also points out that climate change adaptation in China requires the study of integrated technology innovation in different fields, and requires the formation of integrated innovation system in different agencies, so that many a single and independent technical achievement can be integrated into the system, which leads to the establishment of an integrated innovation mechanism for climate adaptation technologies. References | Related Articles | Metrics

Intensities of Agricultural Carbon Emissions and Their Causes in the Major Grain Producing Areas in China TIAN Yun, ZHANG Junbiao, LI Bo 2012, 31 (11):  1546-1551.  doi: 10.11820/dlkxjz.2012.11.016 Abstract ( )   PDF (501KB) ( )   Save While the major grain producing areas in China play a vital role in agriculture, they have become the main source of agricultural carbon emission. Thus scientifically assessing current intensities of agricultural carbon emissions, discrepancies between the areas, and major causes in those areas is an essential prerequisite for making sound policies leading to reduction of agricultural carbon emission. To that end, based on 16 indexes, using principal components analysis, this paper presents the measurement of the agricultural carbon intensity in 13 major grain producing provinces. It shows that the carbon intensities of Hunan, Shandong and Hubei are among the highest three, while those of Jilin, Heilongjiang and Inner Mongolia are among the lowest three. An evaluation matrix of carbon intensity vs. benefits is then created to regroup the 13 areas. As shown in the results, Hunan, Jiangxi, Henan and Anhui are the high-intensity low-benefits areas; Hubei, Jiangsu and Shandong are thehigh- intensity high-benefits areas; Sichuan and Hebei are the low-intensity low-benefits areas; Heilongjiang, Jilin, Liaoning and Inner Mongolia are the low-intensity high-benefits areas. References | Related Articles | Metrics

Diagnosis Based on the PSR Model of Rural Land-use Conflicts Intensity YANG Yongfang, AN Qian, ZHU Lianqi 2012, 31 (11):  1552-1560.  doi: 10.11820/dlkxjz.2012.11.017 Abstract ( )   PDF (1056KB) ( )   Save With the acceleration of industrialization and urbanization, rural land-use conflict has become more frequent. It is of great significance to rural development to analyze the forms of land-use conflict and assess its intensity in different rural areas. This paper presents the studies in the distinctive rural areas of Yanling County from 1990 to 2010. Using correlation analysis and principal component analysis, among the 32 driving factors in the categories of population, social economy and agriculture intensification that cause the changes of arable land-use in Yanling County, 6 major factors are identified. Based on the studies of structural changes of land-use as well as municipal policies and regulations and their effects on the social and ecological environment, an indicator system is established, and the intensity of the land-use conflict is evaluated by using Pressure-State-Response Index of Land-use (ILU). The results show that the pressure on land-use is increasing on yearly basis, the state is deteriorating, and the response is gradually strengthened. Overall, the intensity of land-use conflict in Yanling County has increased from 1990 to 2010. The three major causes for the intensified land-use conflict are as follows: (1) economic development and changes of economic structures. Increase of farmers’income brings changes to way of life and means of work, which in turn affects the composition of workforce and the choice of occupation, and then changes land-use and causes dramatic changes to the industrial structures of Yanling County, leading to intensified conflicts between arable land and construction land, and between arable land and forest land. (2) Changes of agricultural activities. The industrialization of flower and livestock business provides more economic benefits to rural households, constantly drives changes and adjustments in the structure of agricultural activities, and causes land-use conflicts. However, obviously the small business of family-owned contract service conflicts the large-scale operation required by modern agriculture. (3) Influences of the development in science and technology and the government policies, etc. Government policies serve to attenuate the land-use conflicts to some extent. From the conflict management perspective, we propose that government can regulate land-use by utilizing the self-adjustment mechanism of the market and reinforcing the policies on planning. Land-use conflict can be prevented or minimized by improving the effectiveness of land-use through multipurpose planning and balancing, and by standardizing the better ways to use the land. References | Related Articles | Metrics