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    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    SHAO Jing-an, SHAO Quan-qin, LU Qing-shui, HUANG Lin, KUANG Wen-hui
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    The initial participating actions of farmers and herdsmen to government leading ecological construction projects usually possess certain passive characteristics. This study interviews 508 farmers’households from four counties, Mountain-River-Lake of Jiangxi Province and 151 herdsmen’s households in Maduo County, Three-River Headwaters of Qinghai Province, using participatory rural appraisal method. And the differences of the initial responses of their participation to ecological construction projects were understood. The interview data were analyzed by ecological time limits method and EXCEL statistical software. These results showed: 1) The direct actions of farmers participating in ecological construction presented that farmers provided time and labor to complete government leading mountainous afforestation in Mountain-River-Lake. However, the direct participation of herdsmen was reflected by the ecological immigrants that were constituted of the few or no herding livestock in Three-River Headwaters. The rights of mountainous land cleared was the main appropriate means, by which farmers’passive participation actions could be adjusted to ensure farmers participating and benefiting themselves in Mountain-River-Lake. While, for the adjustment of herdsmen’s passive participation actions, the main problems were more considering the changes of herdsmen’s religions and customs, but not merely increasing the standards and years of resettlement compensation in Three-River Headwaters.2) The indirect actions of farmers’participation were the responses of maximizing farmers own interests and helping mountainous land restoration under the stress and shock of foreign powers in Mountain-River-Lake. They were driven by farming opportunity cost increase and breeding risk rise, but not farmers’conscious actions. And the indirect participation of herdsmen was mainly the evolvement result of traditional animal husbandry under the government leading in Three-River Headwaters. "Forbidden-grazing-enclosure-reduced-livestock", as the first responses of herdsmen’s indirect participation, were suitable to mitigate grassland pressure and did not completely change traditional animal husbandry.3) Farmers shifted to non-agricultural industry with the larger initiative in Mountain-River-Lake. It was a spontaneous choice decided by balancing the income gap between agriculture and non-agriculture. The ecological effects after shifting industry presented the pressure of mountainous land were long-term relieved, and a lower bounce risk could be observed. However, herdsmen shifted to non-animal husbandry with the larger passivity in Three-River Headwaters. It was consequent on herdsmen’s passive participation, under the course of government providing some opportunities (e.g., training, employment, education, etc.) and favorable policies, after the game between government and herdsmen for "poor and rich". The bounce risk of grassland ecological improvement was larger after shifting production. The implications of this study help to provide effective data and ideas support for farmers and herdsmen participating in concentric ecological reconstruction and pressure-relief ecological restoration.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WANG Chuan-sheng, ZHU Shan-shan, SUN Gui-yan, FAN Jie
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    Slopes villages refer to villages locating on the slopes of mountains and hills, which are distributed extensively in mountain settlements and constitute an important type of the village settlements in China. The western mountainous areas, which are the main slope village distributed areas, have faced the resources and ecology bottleneck because the long time population growth pressure have made them in recent years the main areas of population movement, and frequent village migrations. With "the Main Function of the National Planning" implemented in the "Twelfth Five-Year Plan on National Economic and Social Development" period, the above regions will be faced the new opportunities and challenges. The spatial reorganization and the population migration in the slope village distributed mountainous areas will be also influenced. And finally the rural household livelihood and sustainable development in mountainous area will be affected. These two problems have exactly long puzzled the western rural development. Accessing the villages space evolution and the peasant households, using the multi-time remote sensing images (TM, ETM, and Alos at 2.5 m resolution) and topographic maps of different scales (1:50000, 1:100000 and 1:250000), the disperse and concentrate characteristics of the two spatial evolutions types of the slope villages were analyzed by using the GIS spatial analysis tools. The concentration is the slope village households’movements from the slope lands down to the smooth lands under the environmental pressure and driven by most of the benefits. One concentration type is its position located on some bigger river valley plains and some main roads are caused by the spatial difference of the slope village’site conditions. Another nearby bigger markets and the advantageous traffic accesses are caused due to infrastructure reconstruction and market mechanism establishment in western mountainous areas. The dispersion is the slope village households’movements up to hills and developing hill slopes for seeking new lands owing to the population pressure. The main reasons for the slope village’s dispersion are the complex terrain, the limited land, the self-sufficient production pattern and the traditional life style of peasants. The rural household questionnaires were prepared in Guyuan and Zhaotong as typical area respectively in the Loess Plateau hilly area and the southwestern mountainous area. The rural livelihoods including the farmlands property, the incomes and the main life style and their changes in the process of the village space evolution and the movement of population are analyzed. The conclusion believed that the spatial concentration and the completely moving out of the slope villages are beneficial to the mountainous area development. The spatial concentration of the slope villages may reduce pressures of resources and environment, enrich livelihood property of the rural households, enhance the income of the indigenous inhabitant, and, by advancing life types of the peasants, build a harmonious developing way between human and environment. However, from another angle, the lower bearing capacity of population and economic activities in the mountainous area limits the slope village’s expansion in scale. And more, owing to lack of the outer communication, the decentralization also may be the normal process of the slope villages’spatial evolution in mountainous area. At that time, the moderate scale household properties, the diversifying household livelihoods, the comfortable living environment, the slope villages’spatial system coordinated with environment, which should be concerned on sustainable development in the mountainous area.
  • ZHOU Sheng-l?, SHI Min-jun, LI Na, YUAN Yong-na
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    This paper aims to assess the economic and environmental effects of fulfilling China’s unilateral international climate policy and non-fossil fuel pledges for 2020. A Chinese Energy-Environment-Economic Model based on CGE model with detailed electricity technologies for China is used to simulate four different mitigation policies. The results show that with 40 yuan/tCO2 of carbon tax rate and use the carbon tax revenues as government income, household income, reduce output tax rate of most impacted sectors by carbon tax, and as the investment of non-fossil energy, can reduce CO2 emission intensity by 35.87%, 35.80%, 35.07% and 40.13% in 2020 compared to 2005, as well as non-fossil energy consumption will account for 10.99%, 11.00%, 10.75% and 15.82% of the total energy consumption, respectively. The mitigation costs under policy scenarios compared to baseline are rather modest and stay below 0.2% of GDP. If the tax revenue is used to alleviate output tax of the most affected industrial sectors, GDP may even increase. This paper suggests that the policy of combining carbon tax with investing non-fossil energy is a good policy choice, which can not only promote the achievement of carbon intensity target in 2020, but also provide funds for non-fossil energy development to stimulate the realization of the non-fossil fuel consumption goal. In addition, taking into account the co-benefits of lower fossil-fuel use suggests that for most mitigation policies considered these benefits outweigh any losses in GDP. Hence, China may benefit from unilateral climate policy in the short run, independent of possible long-term effects on global warming.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    JIAO Shi-xing, WANG La-chun, YANG Shun-xi, LI Yan-dong, ZHANG Yan-ling, YIN Yi-xing, LI Jing, YUAN Huan-huan
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    Urban drinking water sources have an important role in the promotion of social and economic development and stable social order, its comprehensive assessment should be improved in research methods and content. On the basis of "Urban Drinking Water Sources Protection Planning Technology Security Framework", the paper has selected the operable and available 14 indexes of surface water source and 12 indexes of ground water source in terms of water quantity, water quality, management and environmental conditions. Security assessment model of urban drinking water sources was built based on triangular fuzzy numbers. Taking Anyang city of Henan Province as an example, the potential danger rank values and security level of the urban drinking water sources were evaluated compressively. Results show the security level of 10 urban drinking water sources in Anyang city is above average and the potential danger rank values are different. The security degree of the No.2 and No.3 waterworks in Anyang city is very high, without existence of higher potential danger and extremely high potential danger. Seven water sources such as Yuecheng Reservoir, Gongshang Reservoir have high security degree, but their potential danger degrees have evident differences, of which the No.1 and No.4 waterworks in Anyang city assign about 50% to low potential danger, but the No.2 Waterworks in the Huaxian County and the water supply company in Tangyin County and Neihuang County assign about 30% to high potential danger, eventually the No.1 Waterworks in Huaxian County has medium security and assigns only 35% to low security hidden danger and 29% to high security hidden danger. The factors of index layer and rule layer have different influences on the security urban drinking water sources. The profitability of the urban drinking water sources in the index layer is the primary factor influencing Yuechening Reservoir, however, the environmental factor is the most sensitive factor influencing Yuecheng Reservoir. The conclusions show the indicator system and security assessment mode constructed have certain significance to security assessment of urban drinking water sources in China.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WU Wei, XU Zong-xue, LI Fa-peng
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    The Guanzhong Reach is the center of Weihe River Basin, and ecosystem has been disturbed greatly, which impact the economic development in this area. Flow data at Linjiacun, Weijiabao, Xianyang, Lintong and Huaxian stations of the Weihe River are analyzed in this paper, which are the most important stations in the Guanzhong Reach of the Weihe River. Change points are detected by using Sequential Cluster Analysis. Based on the change point analysis, the degrees of hydrologic alteration are analyzed by RVA(Range of Variability Approach) method, and hydrologic parameters that have altered greatly are determined. Results show that the change points are detected in 1986. It implies that the hydrologic regime before 1986 may be more close to natural state, while the hydrologic regime after 1986 has changed greatly because of intense human activity. Supposed that the hydrologic series before 1986 represents the hydrologic regime of pre-impact period, and that after 1986 for post-impact period. According to range of variability analysis, different hydrologic parameters show different alterations. On the whole, the hydrologic regime at five stations has changed obviously, especially that at Linjiacun, Weijiabao and Xianyang stations. These analyses facilitate understanding of hydrologic alteration in the Weihe River, and may be helpful for estimation of environmental flow.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LIU Fang, ZHANG Hong-qi
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    The land use sustainability in main agricultural production regions in China concerns the national food security. Based on the variable weight theory, the paper constructs a sustainability assessment model of land use with indicators covering three pillars of natural resource and environment, economy and society at the county level, with the aim to depict the status and dynamic changes of land use sustainability among the eight agricultural production regions in China. The results showed that, the maps clearly presented the spatial variability obviously existed among the three pillars: natural resource and environmental, economic and social sustainability, and the change range of the latter two aspects was larger than the first aspect between 2000 and 2008. In 2008, Huang-Huai-Hai Plain, middle Yangtze River and Jianghuai region, and Sichuan Basin with the better resource environment and higher GDP, showed a higher natural resource and economic sustainability level than other regions, especially the ecological fragile regions like Xinjiang and eastern part of Inner Mongolia. As for the social sustainability, the sustainability above the moderate level in middle Yangtze River and Jianghuai region, Huang-Huai-Hai Plain and Songnen Plain covered above 90% of the county proportion separately. Between 2000 and 2008, the natural and environmental sustainability in Sichuan Basin, Songnen Plain, Sanjiang Plain and Huang-Huai-Hai Plain showed an increasing trend, with the county proportion increment above 10%, while west of South China, Xinjiang and eastern part of Inner Mongolia showed a decreasing trend. In terms of economic sustainability, different degree improvement occurred in the eight agricultural production regions. The noteworthy was the more contentious human-land conflict in Sichuan Basin and middle Yangtze River and Jianghuai region and the remarkable income gap between urban and rural area in west of South China.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    MA Ai-hui, CAI Yin-ying, ZHANG An-lu
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    In China, limited cultivated land bears great pressure with economic development, so the most severe protection policy for cultivated land in the world has been implemented by the Chinese government for many years, but the present command and control policy has subtle effects. Therefore, how to find a kind of effective measurement to protect the rare cultivated land resources in China is one of the key topics for both land resources protection and ecological environmental construction. The ecological compensation practice of many countries and regions has shown that eco-compensation mechanism is an effective means to solve the contradiction between cultivated land resources protection and economic development, and the accounting and determination of eco-compensation criteria are always the core issues, and also are the key and difficult point in ecological compensation mechanism. This paper takes the stakeholders of cultivated land ecological compensation-citizens’ survey as an example, and uses a new method to evaluate environmental quality, which is a choice experiment method to simulate cultivated land ecological compensation policy and its trading market, and to obtain willingness to pay and quotas of citizens about cultivated land resources protection. Then through a certain econometric model, it can measure citizens’ preferences about attribute of cultivated land protection, including cultivated land area, the quality of cultivated land, the surrounding landscape and ecological environment of cultivated land. This paper also measures welfare level difference value of policy scheme which is a combination of four attributes in cultivated land protection. Two results can be drawn from the study. Firstly, to protect cultivated land resources, citizens focus more on cultivated land ecological landscape surroundings than other properties, and they are willing to pay 154 yuan for improving cultivated land landscape and ecological environment surroundings every year. Secondly, in many attribute combinations, citizens are willing to pay 247 yuan per year for the best policy scheme. That is to say, citizens should pay 247 yuan per year for cultivated land eco-compensation. Different combinations of welfare level difference in value for the cultivated land can contribute to determine a flexible eco-compensation standard in construction of eco-compensation mechanism.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    LI Tian-hong, ZHENG Li-na
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    Soil erosion has become a worldwide environmental problem because it could threaten soil structure, agricultural production, water quality, and so on. During the past decade, much effort has been made to control soil erosion in the Loess Plateau, thus the distribution of soil erosion intensity in this region has experienced a great change. So it is necessary to take more effective soil and water conservation measures and realize the sustainable utilization of water resource by knowing soil erosion changes. Based on RUSLE model, soil erosion changes from 2001 to 2010 in the Yanhe Watershed, a typical hilly-gully region on the Loess Plateau, were studied with the support of GIS and RS. The data set used in the model includes monthly precipitation, MODIS NDVI data, DEM, land use and soil type maps. Having localized the coefficients in RUSLE, the gauged data from Xingzihe Hydrological Station was used to verify the model and the proved reasonable results were produced with this model. The annual soil erosion modulus and the temporal and spatial change of soil erosion intensity in the Yanhe Watershed were analyzed. The main conclusions are as follows: Firstly, in the period 2001-2010, soil erosion in the Yanhe Watershed experienced a decreasing trend from the maximal value of 6596.72 t/(km2穉) in 2001 to the minimal value of 2485.46 t/(km2穉) in 2008, decreased by 62.32%; the soil erosion modulus increased obviously in 2009 because of heavy rainfall. Secondly, the distribution of soil erosion intensity changed obviously and the area ratio of intense, extremely intense, and most intense soil erosion decreased from 16.21%, 21.93% and 12.36% to 10.85%, 4.58% and 0.39% respectively. Thirdly, the transformation matrix of soil erosion intensity indicated that the soil erosion intensity transformed from high level to low level in most of the area with 31.68% of the total area of the watershed from 2001 to 2005 and 42.13% from 2005 to 2010. The distribution pattern of soil erosion intensity during the past decade revealed in this study could provide support for soil and water conservation and ecological environmental construction in the study area and even in the similar watersheds of the Loess Plateau.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    YANG Huai-yu, YANG Zheng-yong
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    Valuation on ecosystem services has been paid much more attention by researchers, decision-makers and the public in the last ten years. However, most current studies are still based on static evaluation framework, dynamic assessment has been scarcely used. In this paper, using the principle and method of system dynamics, the internal structure of pond aquaculture system evaluation of oriental river prawn (Macrobrachium nipponense) is analyzed and its causality and flow chart diagram is given. Then, the mathematical model of aquaculture system is developed with differential equations and simulated with computer, the trend of changes in 30 years about the value of food provision, O2-emission, carbon fixation and costs of eutrophication at different aquaculture strategies has been forecasted. The result shows that: 1) Regardless of any strategy to be adopted, if the external environment of a system can not change, the supply of net value per year of ecosystem services will be stable. 2) Non-market value including O2-emission and carbon fixation is an important and stable source of the value of ecosystem services. 3) In a short period, the change of investment on oriental river prawn aquaculture will result in large fluctuations of the market value of the prawn, but in a long time, with the increase of investments, the market value of the prawn will increase, but the rate of the increment will reduce to zero. 4) On the constraint of assumptions and environments, the outcome of simulations basically accords with the result of actual measurement.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    CHEN Bo, OUYANG Zhu, CHENG Wei-xin, LIU Li-ping
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    To support water resource allocation and planning scientifically, this study analyzed the historical trend of water consumption for winter wheat and summer maize in recent 50 years with Mann-Kendall trend test method. Characteristics of evapotranspiration and water use efficiency (WUE) were presented. Furthermore, the reasons accounting for historical trend of water consumption were proposed by analyzing the trend of water surface evaporation and meteorological factors. Data used in this study came from literatures and long time experimental observations at Yucheng Comprehensive Experimental Station, Chinese Academy of Sciences. Results suggested: 1) The water consumption of winter wheat and summer maize in the North China Plain showed a downtrend in recent 50 years. The water consumption for winter wheat had decreased from 501.2 mm to 456.3 mm, and that of summer maize fluctuated between 300.0 mm and 400.0 mm. 2) WUE for winter wheat and summer maize had been promoted to a large extent. WUE had increased from 3.31 kg/(hm2穖m) to 15.91 kg/(hm2穖m) for winter wheat and from 3.72 kg/(hm2穖m) to 23.36 kg/(hm2穖m) for summer maize. 3) Stages from jointing to milking had high evapotranspiration rate for winter wheat, and several irrigations were needed to meet water demand. Similarly, summer maize in stages from jointing to grain filling consumed more water. However, no additional irrigations were needed due to rainy season. 4) Increase of relative humidity and decrease of sunshine times primarily weakened evaporability, and thus water consumption for winter wheat and summer maize showed a downtrend.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    HU Ying-min, GAO Qiong, LAN Yu-fang, JIN Dong-yan, XU Xia
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    The farming-pastoral zone in northern China has become one of the most vulnerable eco-regions due to the comprehensive effects of climate changes and human activities. As an integral component of ecosystem, vegetation cover dynamics indicated by various vegetation indices from long time series remote sensing data could be used to reflect the ecological and environmental changes. The Grain for Green Project is widely put forward by converting farmland into forests and grasslands, the evaluation of which as a result has become the hot spot of ecosystem researches. Identifying the distinctive impacts of climatic factors and land use management disturbances could help to make more objective assessment of vegetation restoration and guiding the follow-up ecological constructions. This study used Taips County, a typical region in the farming-pastoral zone, as the study area. Based on the data of MODIS-EVI, monthly mean air temperature and precipitation obtained from the nearby 45 weather stations, the spatial-temporal patterns of vegetation cover from 2000 to 2008 were explored. The correlation coefficients between the annual maximal EVI over the whole region and the climatic variables of different months during the growing periods were calculated. Together with the land use data in 2000 and 2005, when northern China was experiencing fast land use shift, we further analyzed the correlation between EVI and climatic variables for different land use types. And EVI changes caused by land use transitions were also studied. The results indicated that from 2000 to 2008, the annual maximal EVI fluctuated with an increasing trend and the vegetation in middle-east of the region grew better than that in the southwest. The average EVI over the whole region of July had a negative correlation with the mean air temperature of June and July and a positive correlation with the total precipitation of the two months. The correlation coefficients were both higher than 0.9, suggesting delayed and accumulative effects. The correlation between EVI and climatic variables of different land use types differed significantly. Before farmland conversions, only the EVI of grasslands had negative correlations with precipitation while after the abrupt land use changes from farmland to forests and grasslands, the EVI of farmland and forests both had higher correlation coefficients than grasslands, interpreting the non-identical results of intensive and extensive land use managements. Different land-use transition patterns resulted in different EVI changes. EVI decreased 2.27% and 1.42% respectively when farmland converted into grassland and forests converted into cropland. The inter-transitions between forests and grasslands also resulted in EVI decrease, pointing out the great uncertainties of environmental protective policies and vegetation restoration projects in case of other natural and human influences.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    ZHANG Yan-jun, GUO Sheng-li, NAN Ya-fang, LI Ze
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    Investigated the changes of soil C:N ratio can help us to understand accumulation of soil organic carbon and nitrogen and tendency of soil quality changes. Based on landforms and land use types, 737 soil samples were collected for investigating the changes of soil C:N ratio and its’influencing factors at a typical small watershed in the hilly region of the Loess Plateau. The results showed that in the condition of 0-20 cm soil layer, in ridge slope soil C:N ratios of woodland and grassland were 1.13 and 1.03 times that of those cropland; in gulley slope the soil C:N ratios of woodland, grassland and cropland were 13.88, 12.58 and 9.02 respectively; in cropland the soils C:N ratios of gulley slope, ridge slope and valley bottom were 9.02, 10.34 and 10.77 respectively; in woodland the soils C:N ratios of gulley slope and ridge slope were 13.88 and 11.67 respectively;in grassland the soil C:N ratio of gulley slope was 1.19 times that of the ridge slope; in the same landforms or land use types, soil C:N ratio was larger in the surface layer than in the deep layer, soil C:N ratios in 0-20 cm and 20-40 cm soil layer were 1.05 to 1.17 and 1.16 to 1.42 times that of those in the deep layer.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    XIE Hua-lin, LI Xiu-bin, ZHANG Yan-ting, PENG Xiao-lin
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    Grassland serves as the basic resources and condition for the survival of human. It is meaningful for us to protect grassland and restore the areas that are seriously damaged gradually as well as refund the natural ecological grassland. It can not only make the land ecological service get a valid guarantee, but also play an important role in the land ecosystem equilibrium and the formation of the regional pattern for ecological security. Strengthening the research on grassland change at the county level about its characteristics, rules, spatial patterns etc., have important sense to guiding the protection of grassland at the county level and realizing the sustainable development of social economy. In this paper, based on global and local spatial autocorrelation analyses of exploratory spatial data, the spatial disparities about grassland change at the county level in Beijing-Tianjin-Hebei Area are discussed by using GIS and Geoda software. The conclusions are as follows: 1) During 1980-2000, the global spatial autocorrelation of forest land changes is significant. Global Moran’s I is the significant positive spatial correlation because it is 0.1844. The spatial clustering phenomenon about the changes of grassland in Beijing-Tianjin-Hebei Area appears on the whole. 2) There is an obviously temporal increase of Moran’s I value from 1980-1995 to 1995-2000. That is, there was a dramatic increase about grassland change’s spatial clustering in Beijing-Tianjin-Hebei Area. 3) The extent of grassland change is almost the same in some region by analyzing the grid figure of Local Moran’s I. Especially, the characteristic of spatial clustering about regional high value and low value is significant. 4) The counties of the positive spatial correlation in local indicators of spatial association are in the majority. The regions with the "high-high" correlation are mainly located in the north-west hilly area during 1995-2000. However, the regions with the "low-low" correlation were distributed in middle area during 1995-2000.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    CAO Yong-qiang, SU Yang, ZHANG Lan-xia, LU Lu, YANG Chun-xiang
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    Using 51 meteorological stations’daily rainfall data from 1960 to 2009 over Zhejiang Province and basing on the index of averaged waiting time for precipitation (AWTP) and wavelet analysis and Kriging spatial interpolation method to analyze temporal and spatial characteristics of droughts in Zhejiang Province. The results show that the trend of drought is increasing in recent years; in 50 years, the maximum value of equivalent dry period reaches 52 days in 1979; there is a clear inter-annual and decadal variation in the trend of change; there are three years of primary cycle on Zhejiang Province’s drought. At the same time it shows that Zhejiang has a significant regional drought, which increases from south to north; the drought of Pinghu and Jinhua of western Zhejiang is more evident than the other regions; west Hangzhou, Wenzhou, Taizhou and partial southern places come the second place; that of Ningbo, Shaoxing and Huzhou is the lightest.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    JIA Yan-long, XU Zhong-qi, JI Xiao-lin, XU Xue-hua, HUANG Xuan-rui
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    In order to understand the difference between plantation and secondary forest as a carbon sink, we chose an age sequence of Larix principis-rupprechtii plantation and secondary poplar-birch forest respectively for the study of biological carbon storage in north region of Yanshan Mountain. Result showed that: Total biological carbon storages in 13-, 18-, and 28-year old secondary poplar-birch forest are 27.33, 35.77, 46.13 t/hm2, and 9-, 13-, and 30-year old Larix principis-rupprechtii plantation are 21.97, 34.14, 55.62 t/hm2, respectively. Yearly carbon accumulation rates in secondary forest are 2.10, 1.69, 1.04 t/hm2 for 0-13, 14-18, and 19-28 years stand respectively. And the rates in plantation are 2.44, 3.04, 1.34 t/hm2 for 0-9, 10-13, and 14-30 years stand respectively. Larix principis-rupprechtii have a high speed individual tree biomass accumulation. At tree age of 10-25, individual tree biomass accumulation rate in Larix principis-rupprechtii is 5.83-1.63, 7.87-2.26 times faster than in birch and in poplar respectively. Biomass conversion and expansion factor (BCEF) and biomass expansion factor (BEF) for Larix principis-rupprechtii decreases gradually with increasing age and DBH, but increases gradually for the two factors of birch and poplar. It is concluded that compared with secondary poplar-birch forest in north region of Yanshan Mountain, Larix principis-rupprechtii plantations have a powerful carbon sequestration capacity and have huge carbon storage potential for the existence of massive young and middle age trees. Application of biomass factors should consider the effect of tree species, age and DBH.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    WANG Zhong-qiang, ZHANG Xin-yu, MENG Xian-min, SHENG Lian-xi, WANG Sheng-zhong, HE Chun-guang, HOU Jia-zhi
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    Peat is a carbon-rich resource by long-term accumulation in mire, and it plays not only the key role to global carbon conservation but serves also as the most important media to horticultural industry. There has been the controversy to peat whether being protected or utilized due to its scarcity and versatility, so researches on peat substitute will be of great significance for peat protection and horticultural production. The paper summarizes the process and key factors for peat formation so as to provide some new ideas and method for peat substitute research.