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  • Articles
    CUI Peng, LIN Yongming
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    Due to special topographical, geological and meteorological conditions, debris flows occur frequently and result in heavy losses of lives and properties in mountainous areas, which become a great threaten to the sustainable development of regional economy and society in western China. At present, debris-flow prevention has performed well in many mountainous countries and has made headway in early warning, disaster mitigation by structural engineering methods, and risk analysis and management. In this paper, debris-flow prevention techniques have been introduced from the aspects of botanical methods, geotechnical engineering methods, and synthetic prevention system based on the above two methods. In addition, the treatment system of multilevel runoff and unconsolidated soil in the catchment with a chain of “slope-gully-valley” is set up in consideration of sediment load of main rivers, incorporation of slope improvement and gully retention, as well as micro-site factors for matching species with the site. Furthermore, attentions should be paid to the mechanism and technical details of vegetation measures for debris-flow prevention, as well as effective incorporation between botanical method and geotechnical method.
  • Articles
    CHU Ying, WANG Shaoqiang, WANG Jingyuan, Matthias PEICHL, Samereh FALAHATAR
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    Soil dissolved organic carbon (DOC) is an active fraction of the soil organic carbon (SOC) pool and links terrestrial and aquatic systems. The degradation of DOC can affect carbon cycling, nutrient dynamics and energy supply to microorganism, and consequently change biogeochemical processes. This study investigated the vertical and seasonal variability of soil DOC concentrations and its controls in a 23-year-old planted slash pine (Pinus elliottii) forest at Qianyanzhou Forest Experimental Station (QFES) in Southern China. Soil solutions were collected at bimonthly intervals at depths of 10, 20 and 30 cm by a mechanical-vacuum extractor from November 2007 to March 2009, and at monthly intervals at depths of 10, 30 and 50cm from April 2009 to October 2010. The DOC concentrations were determined with a total organic carbon (TOC) analyzer. Mean (±standard deviation) DOC concentrations at depths of 10cm, 20cm, 30cm and 50cm were 12.4±4.4, 10.6±6.3, 8.7±2.6, and 8.0±5.9 mg L-1, respectively. Both seasonal and spring means of DOC concentration showed a decreasing trend with increasing depth, while there was no clear trend for the summer, autumn, or winter seasons. DOC concentrations during spring, summer, autumn and winter ranged from 4.8 to 21.5, 4.9 to 26.2, 5.4 to 17.1, 4.9 to 14.6 mg L-1, respectively, their mean DOC concentrations were 10.2, 10.5, 10.8 and 8.3 mg L-1, respectively. No consistent pattern of seasonal variability of DOC concentrations at different depths was observed. No obvious relationship between organic carbon content of forest litter and DOC concentration was found. There was a positive linear relationship between SOC and DOC concentration (R2=0.19, p<0.01), which showed that SOC was one of the main controls of DOC. A positive exponential relationship existed between soil temperature at 5 cm and DOC concentrations at 10 cm depth in slash pine, masson pine (Pinus massoniana) and Chinese fir (Cunninghamia lanceolata) planted forests (R2=0.12, p<0.01). DOC concentrations showed a negative linear relationship with soil moisture at all depths in slash pine forest (R2=0.15, p<0.001), and DOC concentrations at depth of 10 cm demonstrated a negative exponential relationship with soil moisture at 5 cm depth in three planted forests (R2=0.13, p<0.001). Precipitation in sampling months and mean seasonal DOC concentration were not correlated. However, a more detailed analysis of precipitation events at different times before sampling and seasonal DOC concentration showed that the timing of precipitation events prior to sampling had different effects on seasonal DOC concentrations at different depths. Our study highlights the importance of DOC dynamics for the carbon cycle in planted slash pine forest and it provides evidence for evaluating the effects of ecological restoration in subtropical red soil region.
  • Articles
    TAO Yuhua, Roger A. WILLIAMS
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    Carbon (C) stocks and sequestration rates were determined for oak-hickory forests in Ohio, USA. The models we developed show that the patterns of C sequestration rates follow what we expect in total and merchantable volume increment. The current annual increment (CAI) and the mean annual increment (MAI) peaks at ages 23 and 46 years, respectively, for total aboveground C. The peak CAI and MAI for the aboveground C peaks at ages 26 and 53 years, respectively. The 5-year periodic MAI for both total aboveground C and aboveground portion of merchantable trees occurs at age 30 years, occurring simultaneously with the 5-year periodic MAI for total and merchantable volume. Knowing that C sequestration occurs in similar patterns to volume growth is helpful in transitioning from traditional volume-based management to carbon-based management.
  • Articles
    ZHAN Xiaoyun, YU Guirui, HE Nianpeng
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    We conducted a systematic census of leaf N for 102 plant species at 112 research sites along the North-South Transect of Eastern China (NSTEC) following the same protocol, to explore how plant functional types (PFTs) and environmental factors affect the spatial pattern of leaf N. The results showed that mean leaf N was 17.7 mg g-1 for all plant species. The highest and lowest leaf N were found in deciduous-broadleaf and evergreen-conifer species, respectively, and the ranking of leaf N from high to low was: deciduous > evergreen species, broadleaf > coniferous species, shrubs ≈ trees > grasses. For all data pooled, leaf N showed a convex quadratic response to mean annual temperature (MAT), and a negative linear relationship with mean annual precipitation (MAP), but a positive linear relationship with soil nitrogen concentration (Nsoil). These patterns were similar when PFTs were examined individually. Importantly, PFTs, climate and Nsoil jointly explained 46.1% of the spatial variation in leaf N, of which the independent explanatory powers of PFTs, climate and Nsoil were 15.6%, 2.3% and 4.7%, respectively. Our findings suggest that leaf N is regulated by climate and Nsoil mainly via plant species composition. The wide scale empirical relationships developed here are useful for understanding and modeling of the effects of PFTs and environmental factors on leaf N.
  • Articles
    GUO Juan, LIU Changxin, SUN Ping
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    We use the refined Laspeyres index decomposition method to determine the main CO2 emissions from industry and analyze differences in these over the period 1994-2007. Then we examined the decoupling state between carbon emissions and economic growth and the effectiveness of the implementation of emission reduction policy. We found that output effect is the dominant positive factor for carbon emissions growth in China’s industrial sectors, and the effect of energy intensity change is the mainfactor affecting carbon emission reductions; the impact of these two factors is respectively 357.20% and -248.67%. The food industry, textile industry and machinery industry show a decreasing trend in emissions, and emissions from the oil industry increased by 217.75%. From 1994 to 2007 and 2000 to 2007, the decoupling index of carbon emissions and the industrial sector was 0.63 and 0.56 respectively. This indicates carbon emissions and economic growth are in a weak decoupling state, and emission reduction policies lack efficacy. These findings can be used in the design of policy priorities for improving decoupling across industrial sectors.
  • Articles
    HU Ruishan, DONG Suocheng
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    Land use change and landscape patterns have a large effect on land productivity and ecosystem biodiversity. Based on geographical information system technology and remote sensing data related to land use and land cover of Jiangsu and Zhejiang provinces and Shanghai (Jiang-Zhe-Hu area), we analyzed patterns of landscape change and predicted land use dynamics using the CA-MARKOV model. We also analyzed the conversion rate and area among landscape classes using the CA-Markov model. We found that from 1980 to 2005, there was a significant decrease in the area of farmland, and much of this landscape was transformed into settlements. Most of the landscape classes have become fragmented and isolated. The areas of farmland, settlement land and water tend to be complex in their shape and spatial clustering. The shapes of other land class patches have become simpler, and overall landscape fragmentation has increased. Landscape diversity and heterogeneity have increased. The CA-MARKOV model predicted that settlement land will continue to grow from 2005 to 2015, but the speed of conversion will be reduced. The speed of the reduction in farmland and forest has increased, and increased settlement areas are clustered along the Yangtze River. Land use dynamics and change in the landscape pattern have affected land productivity and made the ecosystem more sensitive and fragile in this study region.
  • Articles
    LI Yajuan, CHEN Tian, HU Jing, WANG Jing
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    The concept of ecological security stems from environmental security theory, and is generally used to evaluate the ecological security of land, water resources and the city. This study applies the Pressure-Station-Response (P-S-R) model and theory of ecological security with field research in 2010 to establish an index system for tourism ecological security evaluation. The findings show that tourism ecological security in Wuhan has increasingly improved from a comprehensive evaluation value of 5.8023 in 2004 to 6.459 in 2010, and has moved from a “sensitive” condition to “safe” condition. Ecological pressure and ecological response are negatively correlated, and the value of ecological response was below that of ecological pressure during the seven years. In order to make clear the impact factors affecting tourism ecological security in Wuhan, this paper summarizes ten limiting factors influencing tourism ecological security and makes several recommendations to improve tourism ecological security.
  • Articles
    FAN Jie, HU Wangshu, CHEN Dong, SUN Wei
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    The aesthetic perceptions of local residents towards residential landscapes are significant to the protection and sustainable development of regional landscapes, especially in underdeveloped areas with landscape resources of higher aesthetic value. Using Nujiang Lisu Autonomous Prefecture in Yunnan Province as a case study, we conducted questionnaires with 620 local residents and a logistic regression model to determine aesthetic perceptions and factors affecting these perceptions. We found that local residents in Nujiang hold a relatively high perception of their residential landscapes. A majority of respondents, 75.81%, believe their residential landscapes are beautiful. Eight factors were found to influence the aesthetic perception. In direct influential factors, administrative village located in the protected areas and the standard deviation of the elevation around the administrative village have positive influence; distance from administrative village to county town, the ecological environment has changed in recent years, whether tourism development has a negative impact and wish to live in the city have negative influence. In indirect influential factors, both residential house type and have a television at home have positive influence. Based on these results, we discussed relevant policy suggestions to maintain the aesthetic perceptions held by local residents of their residential landscapes and promote the protection and sustainable development of this valuable landscape in Nujiang.
  • Reports
  • Reports
    ZUO Qiting, MA Junxia, TAO Jie
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    Chinese water resource management (CWRM) has passed through four stages: infancy, initial development, rapid development, and formation. In the last of these stages some problems persist and will affect management performance. CWRM was a decentralised, imperfectly codified and weakly implemented system that lacked a sound market policy, rational water prices, water conservation awareness, technical support and a performance appraisal system. The government of China proposed two new strategies in 2009: the Three Red Lines and the Interconnected River System Network (IRSN). This paper analyses these two strategies and reflects on new CWRM concepts. Both strategies strive for the sustainable utilisation of water resources and human-water harmony. The concepts, quantification method and application of harmony theory to water resources management is discussed. Applications of harmony theory to water resources management include (i) harmony between humans and nature; (ii) a harmony strategy for water resources management; (iii) a rational allocation model for water resources among different areas and departments based on harmony theory; (iv) harmony-based water allocation issues associated with transboundary rivers; (v) harmony-based interbasin water transfer problems; and (vi) harmony-based control of pollution discharge. We conclude by discussing how harmony theory and its applications provide an appropriate pathway for water resource management in China.
  • Reports
    ZHOU Hong, GU Shuzhong, YAO Yulong, WANG Limao, HU Yongjun
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    We analyze the mechanism of natural resource regulation on regional economic growth and estimate the model based on panel data for 31 Chinese provinces from 2000 to 2009. Our findings suggest that a fixed effect model is more appropriate than a mixed cross section or random effect model. A fixed effect model between natural resource regulation and regional economic growth quantity and quality was constructed to check the validity of natural resource regulation on regional economic growth. We found that natural resource regulation is effective at regulating regional economic growth; and natural resource regulation restrains regional economic speed to some extent. The per unit growth of natural resource regulation intensity will cut 24.6 billion CNY in gross domestic product; however, natural resource regulation can improve the quality of regional economic growth. Growth in the per unit natural resource regulation intensity will increase the index of regional economic growth quality by 0.022 units. In summary, these data support the proposal for using natural resources to regulate regional economic growth and transformation.
  • Reports
    ZHANG Yan, GAO Xiang, ZHANG Hong
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    Here, we estimate the rationality of specific agricultural inputs and discuss the sensitivity of integrated agricultural output to various resources input for Chaohu City, China. We used two parameters, marginal output and elastic coefficient, and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method, which has an unambiguous geometric meaning and is simple and convenient, to integrate various output and input. The results indicate that for most of 2001-2009, agricultural inputs rose except that the number of people engaged in agricultural production fell. Although integrated agriculture output increased, the proportion of resources with a negative utilization efficiency was 23.82% from 2001 to 2009. Integrated output was more sensitive to agricultural pesticide, the irrigation ratio and the use of plastic film. Integrated outputs may be increased by moderate decreases in input. This type of agricultural production meets the requirements of resource saving and is a sustainable mode of resource utilization.
  • Reports
    ZHANG Leqin, CHEN Suping, ZHU Yawen, XU Xinwang
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    In the context of “two-wheel drive” development mode, China’s construction land shows significant expansion characteristics. The carbon emission effect of construction land changes is an important factor for the increase of carbon emissions in the atmosphere. In this study, the drivers of carbon emissions in Anhui Province from 1997 to 2011 were quantitatively measured using the improved Kaya identity and Logarithmic Mean Divisia Index. The results show that: economic growth, expansion of construction land and changes in population density have incremental effects on carbon emissions. The average contribution rate of economic growth as the first driver is 266.32 percent. The construction land expansion is an important driving factor with annual mean carbon effect of 6.4057 million tons and annual mean contribution rate of 187.30 percent. But the change in population density has little impact on carbon emission driving. Energy structure changes and energy intensity reduction have inhibitory effects on carbon emissions, of which the annual mean contribution rate is -212.06 percent and -158.115 percent respectively. The targeted policy approaches of carbon emission reduction were put forward based on the decomposition of carbon emission factors, laying a scientific basis to rationally use the land for the Government, which is conducive to build an ecological province for Anhui and achieve the purpose of emission reduction, providing a reference for the research on carbon emission effect of changes in provincial-scale construction land.