Loading...

Table of Content

    20 August 2016, Volume 31 Issue 8 Previous Issue    Next Issue
    Resource Ecology
    Monitoring the Evolution of Wetland Ecosystem Pattern in Northeast China from 1990 to 2013 Based on Remote Sensing
    MAO De-hua, WANG Zong-ming, LUO Ling, REN Chun-ying, JIA Ming-ming
    2016, 31 (8):  1253-1263.  doi: 10.11849/zrzyxb.20151005
    Abstract ( )   HTML ( )   PDF (5547KB) ( )   Save
    With the background of global change, wetland has great sensitivity and vulnerability. In order to investigate the dynamics of the spatial characteristics and heterogeneity of natural and human-made wetlands in Northeast China, the ecosystem pattern of six important wetland regions in the study area in 1990, 2000 and 2013 were rebuilt based on satellite images of Landsat TM, ETM+, OLI and Chinese HJ. Results indicated that the area of wetlands in Northeast China in 1990, 2000 and 2013 was 11.75×104, 10.57×104 and 10.41×104 km2, respectively. The distribution of wetlands had obvious regional features. There are more natural wetlands in the Greater Khingan Mountains wetland region, while there are more human-made wetlands in the Liaohe Delta wetland region. Notable loss of wetlands was observed in Northeast China during 1990-2013 (11.4% of wetland, 14.3% of natural wetland). Most of the disappeared wetlands were converted to croplands. The most significant decrease of wetland area was observed in the Sanjiang Plain with a loss of 9 935.2 km2 for natural wetlands, however significant increase of human-made wetland area was observed in the Songnen Plain, with an increase of 1 141.9 km2. There were clearly spatial differences in the impacts of climatic and human factors on the wetlands. Based on the changing trends of wetland, climate and human factors, human activities were the leading driving force for the losses of wetlands.
    References | Related Articles | Metrics
    Assessment of Land Ecological Risks Driven by Multi-sources: A Case Study of Sheyang County, Jiangsu Province
    YU Yan-na, ZHU Jiang, WU Shao-hua, ZHOU Sheng-lu, LI Bao-jie
    2016, 31 (8):  1264-1274.  doi: 10.11849/zrzyxb.20151104
    Abstract ( )   HTML ( )   PDF (3977KB) ( )   Save
    Land ecosystem including nature subsystem and social subsystem is an important part of global terrestrial ecosystem, which supports human beings’ livelihood. With rapid urbanization and the social progress, the land-use of China transformed significantly and this process changed the structure and function of land ecosystem. Those changes led to further degradation of land ecosystem driven by multiple risk sources. Thus,it is of great significance to evaluate land ecological risks in order to guide the exploitation of land resource. We proposed a method to assess land ecological risks by combining the occurrence probabilities of multi-sources risks, the resistance and resilience of land ecosystem and possible damages when land ecosystem is exposed to risky environment. This paper quantified and spatialized the land system ecological risks using tools in geography information system. This paper took Sheyang County of Jiangsu Province for example. Based on the practical condition of Sheyang and the feasibility of data acquisition, several targets were selected to calculate the land ecological risk source index, nature system resilience index and damage index, social system reliance index and damage index, nature system risk index, social system risk index and complex system risk index. The result showed that: 1) The soil pollution, soil sealing and water pollution play an important role in land ecosystem risk source index. The land ecosystem risk source index is much higher in urban area than in rural area, which shows the risk sources index is closely related to the urbanization progress and the socioeconomic development. Urbanization progress brings more risk sources. 2) The town center of Sheyang is the region with the highest social system risks, while the region of the highest nature system risk locates in the nature reserve of eastern Sheyang which is bounded by the Huanghai Sea, therefore. In these two regions, more attention should be paid to ecological protection and restricted construction. 3) When it comes to the complex system risk index, the highest value appears in the nature reserve near Huanghai Sea, being less than 0.5 in the core zone of the nature reserve. The town center also shows relatively high value of the complex system risk index. Lower values distribute in large areas in the east of Sheyang and around the town center. It is suitable for urban expansion and land development in these regions. Correspondingly, it needs to restrict the expansion of the nature reserve and the town center. According to the research results, this paper proposed diversified land ecology policies in different regions of Sheyang, which can provide decision-makings for urbanization and ecological environment protection in Sheyang. It is proved by the research results that the assessment model of land ecological risks presented in this paper has high precision and can express regional land ecological conditions very well. This model can provide a reference for further work of quantifying land ecological risks.
    References | Related Articles | Metrics
    Estimating the Spatio-temporal Characteristic of Vegetation Water Use Efficiency over Weihe River Basin
    WEI He-jie, ZHANG Yan-fang, DONG Xiao-bin, LU Na-chuan, WANG Xue-chao
    2016, 31 (8):  1275-1288.  doi: 10.11849/zrzyxb.20151064
    Abstract ( )   HTML ( )   PDF (7471KB) ( )   Save
    Water Use Efficiency (WUE) can be used to describe the relationship between “water loss” and “carbon fixation” of plants in the process of photosynthesis, which is an important variable to link ecosystem carbon and water cycles. Estimating WUE with remote sensing data can enhance our ability to reveal how global change affects water and carbon cycles. Based on triangle model and CASA model which is used to estimate evapotranspiration (ET) and net primary production (NPP), this paper constructs the WUE remote sensing estimation models with improved water limiting parameters. Using the constructed model, this paper acquires the WUE of vegetation over the Weihe River Basin in 2010 based on MODIS imagery and meteorological data. Then this paper studies the relationship between WUE and temperature or precipitation. Results are shown as follows: 1) The results of WUE estimated by different WUE models are different because these models are based on different definitions of WUE, different simulation areas, different data sources or different vegetation classifications. 2) The monthly variation of WUE roughly shows a double peak pattern over the Weihe River Basin in 2010 with the highest value in August. The seasonal WUE shows that the maximum value is in summer (1.05 gC·m-2·mm-1), followed by autumn (0.66 gC·m-2·mm-1), spring (0.57 gC·m-2·mm-1) and winter (0.12 gC·m-2·mm-1). 3) The spatial distribution of WUE shows that the high value pixels are in the forest region of Ziwuling, Huanglong Mountain, Liupan Mountain and the northern slope of Qinling, while the low value pixels are in the built-up regions of Xi’an city, low vegetation coverage regions of upper basin and some dry farming areas. 4) With the increase of temperature, the change of WUE can be divided into five stages, which are essentially invariant, slightly increased, rapid increased, stable and declined. With the increase of precipitation, the change of WUE over the Weihe River Basin also can be divided into five stages, which are rapidly increased, slowly increased, stable, slowly declined and rapidly declined.
    References | Related Articles | Metrics
    Resource Utilization and Management
    The Occupation of River Network by Urban-rural Land Expansion in Taihu Basin, China
    SU Wei-zhong, CHEN Wei-xiao, GUO Wei, RU Jing-jing
    2016, 31 (8):  1289-1301.  doi: 10.11849/zrzyxb.20151137
    Abstract ( )   HTML ( )   PDF (10852KB) ( )   Save
    Rapid processes of urbanization have altered the natural processes of river network structure in the watershed and led to the degeneration of ecological service functions, such as flooding storage and biodiversity. The paper proposed a new concept of urban-rural river, which links the urban-rural land with the topology structure of the river system, and measured the occupation of river network by the urban-rural land expansion. Urban-rural river are transformed from natural rivers in the watershed enveloped or overlaid by the urban-rural land which alter the natural processes and functions. It can be a spatial feature indicating the impact of urban-rural development on the river network. Based on the urban-rural river density (URRD) and the characteristics of 490 spatial units of sub-basins, the paper measured and revealed the impact of urban-rural development on river structure in the Taihu Basin. The URRD increased from 57.10 m/km2 in 1985 to 122.28 m/km2 in 2010, and the leading structure changed from low level to high level. The growth of URDD centered at the cities in the important development belts, such as Shanghai-Nanjing, Shanghai-Hangzhou and along Yangtze River. There was a weak correlation between the URRD and the river density (RD), and a significant correlation between the URRD and the urban-rural land density (URD), however, the correlation coefficient was different in different phrases of urban-rural development, such as in the phases of URD 0-15% and URD 25%-40% they had the most significant correlation. Based on the statistics of samples in sub-basins and study of typical cases, the changes of the correlation may be linked with the different patterns of urban-rural land growth in different development phrases. The urban-rural river resulted from the urban-rural land expansion in the watershed, and presented a spatial difference in the watershed owing to the growth pattern of urban-rural land, such as infilled growth or intensive growth. Thus, the strategies is proposed to coordinate the spatial patterns of the urban-rural land and river networks, such as protective, defensive and offensive, which can adapt to different development phrases of urban-rural land expansion in the sub-basins.
    References | Related Articles | Metrics
    A Study on Efficiency and Equity of Rangeland Management on Qinghai-Tibet Plateau in Different Property Right Systems
    CAI Hong, LI Wen-jun
    2016, 31 (8):  1302-1309.  doi: 10.11849/zrzyxb.20141650
    Abstract ( )   HTML ( )   PDF (946KB) ( )   Save
    Based on field studies in Ruoergai County of Sichuan Province, this paper conducts a comparative analysis on the efficiency and equity of rangeland resource in two different rangeland property systems: private rangeland use-right and community rangeland use-right. The findings of this research demonstrate that community collective use of rangeland is more effective in promoting rangeland management equity and efficiency compared to the privatized use-right regime. This is mainly because the community collective regime is more suitable to the local natural and social characteristics, including the temporal and spatial heterogeneity of rangeland resource distribution, the strong role of pastoralism culture that are embedded in the Tibetan Buddhism, and the ability of community self-organization in rangeland management. Given this, we recommend that policy makers should take local natural characteristics and socio-cultural backgrounds into consideration when designing and implementing rangeland property right regimes, and avoid implementing uniform property arrangement in all pastures across the whole country.
    References | Related Articles | Metrics
    Plastic Film Residue and Farmers’ Willingness of Film Recycling in the Oasis Area of the Heihe River Basin, China
    XIN Liang-jie, LI Peng-hui, LI Xiu-bin, TAN Ming-hong, ZHENG Lu-qian, XIAO Xing-yuan
    2016, 31 (8):  1310-1321.  doi: 10.11849/zrzyxb.20151084
    Abstract ( )   HTML ( )   PDF (2447KB) ( )   Save
    Plastic film mulching plays an important role in China’s increasing agricultural production due to its soil warming and moisture conservation effects. According to China Agricultural Statistical Yearbook 2014, the volume of plastic film mulch used in China increased to 136.2×104 t in 2013, and the total crop area covered with plastic film mulch similarly increased to 1 765.7×104 hm2. Now, China ranks the top in the world in terms of the use of plastic film mulch. While producing huge benefits, plastic film mulch technology has also brought on a series of pollution hazards.
    In order to investigate the status quo of mulch residue, a detailed household survey in the oasis area of the Heihe River Basin, China, was conducted by the authors with the help of Hexi University in July, 2014, and 131 valid questionnaires were obtained. A Probit model and a multi-variable regression model were built to understand the influencing factors of mulch recycling rate.
    Based on the survey data and regression models, some conclusions about plastic film residue and the factors affecting farmers’ willingness of film recycling were obtained. Firstly, agricultural plastic film mulching is widely used for almost all crops in Zhangye. The crop area covered with plastic film mulch accounted for 69.9% of the total in 2014. Secondly, the rate of residual film in Zhangye was 25.7% on average in 2014, and the amount of residual film in Zhangye in 2014 reached 63.75 kg/hm2, equal to the amount of plastic film applied on the corn field in this area. The level of residual agricultural film is obviously higher than the level in Inner Mongolia region and the North China, nearly reaching the limit of national standard. Although plastic film can increase soil temperature and conserve moisture, corn covered with plastic film mulch still cannot cope with low temperature and less water in the hilly regions of Zhangye. So farmers in the counties of Shandan and Minle prefer to plant wheat and barley rather than plant corn. The height limit of film application is about 2 100 m.
    In the plain region of the middle reach of the Heihe River, higher wage has a negative impact on the rate of film recycling. Higher wages reduce the dependence of farmers on agricultural income and increase the opportunity cost of farming. Farmers are unwilling to input more labor in the field. Farmers prefer to apply black film in vegetable fields and the recycle rate in vegetable fields is higher than that in grain fields, because vegetable can bring higher profit than grain crops and vegetable fields need higher soil quality. More plots mean more commuting time. So farmers with more plots usually manage their lands extensively, which caused the low recycling rates. Agricultural labor input and the elevation of farmer’s houses have positive impacts on the rate of film recycling. It is worth noting that the educational level of the household head and agricultural subsidy have no impacts on the recycling rate of agricultural film.
    The policy implications are as follows: 1) the quality of plastic film should be improved obviously so that it can be easily picked up; 2) the development of plastic film recycling machine should be sped up in order to reduce the increasing labor cost; and 3) research and development of biodegradable mulch film should also be improved
    References | Related Articles | Metrics
    Resource Economy
    Interactions between Efficiency, Resources and Mechanism of Urban Tourism: A Comparative Study of 49 Chinese Excellent Tourism Cities
    XU Xiao-bo, ZHAO Lei, WU Bi-hu, LIU Bin-yi, ZHONG Li-na
    2016, 31 (8):  1322-1338.  doi: 10.11849/zrzyxb.20150844
    Abstract ( )   HTML ( )   PDF (3181KB) ( )   Save
    Urban tourism has become a research focus at home and abroad. Meanwhile, domestic research in this area should situate itself in China’s urbanization contexts. As pointed out by many researchers, more analysis should be conducted on key issues such as efficiency, resources, mechanism and effects of urban tourism. This paper aims to advance the knowledge of correlations between tourism efficiency, urban resources (attributes) and development mechanism of Chinese tourist cities. To this end, 49 excellent tourist cities in China are selected to make a multi-case and comparative study. Data is collected from more than 11 000 pieces of online narrative texts published on a well-known Chinese tourism business website www.ctrip.com, all of which are remarks of unknown tourists after their visiting the studying cities. Research methodologies of content analysis, importance-performance analysis, cluster analysis, ANOVA, block-modeling and TOPSIS are employed. It is found that tourism efficiency is not in line with yet affected by urban resources qualification, but determined by tourism development mechanism. Besides, both tourists’ perception and satisfaction levels fluctuate evidently with urban resources, which therefore can serve as the discrimination credits for group-identification of tourist cities. Among these resources, each of 13 is suggested to be critical indicators according to tourists’ perception and satisfaction. A further analysis shows that the 49 sample cities fit into four groups, which are nominated, respectively, function-prominent group, combinative group, resource-prominent group and tourism-specified group. Differences among these four groups are detailed in terms of tourism development mechanism. The catalyst role of traditional tourism resources to the development mechanism of urban tourism can be identified through a summary review; also the characterizing attributes or resources of the city per se hold a large stake in promoting tourists’ satisfaction. It is concluded that tourists’ perception levels tend to be extroversive from high-perceived resources, while satisfaction levels introversive to the most-prominent attributes. These findings might be inductive for policy-making of Chinese tourist cities.
    References | Related Articles | Metrics
    An Empirical Research on the Coupling Coordinative Relationship between Regional Tourism and Informationization
    WANG Guan-xiao, LIANG Liu-ke, LI Feng, JIANG Si-yuan, DUAN Xiao-wei
    2016, 31 (8):  1339-1350.  doi: 10.11849/zrzyxb.20151154
    Abstract ( )   HTML ( )   PDF (1632KB) ( )   Save
    This paper aims at constructing the evaluation index system of coupling coordination between regional tourism and informationization. By using efficacy function, comprehensive evaluation function, and the index of coupling coordination degree, the coupling coordinative level of 31 provinces in China (not including Hong Kong, Macao and Taiwan due to no data) was quantitatively evaluated. Then, the coupling coordination relationship between tourism and informationization of each province was classified into different grades and types with the distribution matrix of coupling coordination. The results showed that: there were great gaps in the levels of tourism and informationization among provinces, and the provinces with higher level of informationization were mostly economically developed provinces, including Guangdong, Beijing, Jiangsu, Zhejiang, Shanghai and Shandong. The differences among provinces in the social application, infrastructure and development environment of informationization, tourism personnel training and tourism economic effect were significant. However, due to the coupling coordination mechanism of tourism and informationization, the difference between tourism and informationization was kept in a certain range, which resulted in that the coupling degrees of most provinces were in high level, 29 provinces with coupling degree above 0.6. The coupling coordination degree is more dependent on the comprehensive strength in terms of economy, technology and talent, so the differences of the coupling coordination degree among provinces were great, that the coupling coordination degree of Guangdong Province was the highest, being 5.57 times as high as the coupling coordination degree of Tibet which was the lowest among all provinces. The level of coupling coordination of tourism and informationization presented distinct spatial differentiation. The provinces around Bohai sea, the Yangtze River Delta and the Pearl River Delta were in the moderate or higher grades of coupling coordination, while the central and western provinces other than Sichuan and Hubei were all in the moderate or lower grades of coupling coordination. Except Beijing, Guangdong and Jiangsu, all provinces had the mode of tourism-leading or synchronous development of tourism and informationization. Based on above results, in the future we should take measures to promote continuous and coordinated development of tourism and informationization, such as promote informationization, accelerate the application of information technology in the tourism, promote the integration of tourism industry and information industry, strengthen the cross regional cooperation, etc.
    References | Related Articles | Metrics
    Carbon Sequestration Efficiency of Four Forest Regions in China: Measurement, Driving Factors and Convergence
    XUE Long-fei, LUO Xiao-feng, WU Xian-rong
    2016, 31 (8):  1351-1363.  doi: 10.11849/zrzyxb.20150985
    Abstract ( )   HTML ( )   PDF (1121KB) ( )   Save
    This paper brings forestry carbon sequestration into the forestry economic accounting system, building a DEA-Malmquist index containing positive externality output. Based on the systematic measurement of forestry carbon sequestration, it estimates forestry production efficiency and the driving factors of the four forest regions of China from 1988 to 2013, and then using σ convergence and absolute β divergence analysis method, it checks the convergence of forestry production efficiency. The results show that: due to the differences of forest intensive degree and industrial development, the carbon sequestration and carbon sequestration value also have big difference among the four forest regions, the total output values of carbon sinks from high to low are: in the first place, the carbon sequestration value in the Southwest Forest Region is 187.069 billion yuan; in the second place, the carbon sequestration value in the Northeast Forest Region is 133.541 billion yuan; came in the third place is the South Forest Region, the carbon sequestration value being 84.273 billion yuan; on the bottom of the list is the North Forest Region, the carbon sequestration value being 40.735 billion yuan. The Malmquist index without considering the carbon output of forestry production is low, 0.958. When taking the carbon sink of forestry output into consideration, the efficiency is then improved at an average annual growth rate of 0.6% from 1988 to 2013, and the main reason is the improvement of technical efficiency. In the South Forest Region and Northeast Forest Region, the production efficiencies are in the upgrading trend, while in the Southwest Forest Region and North Forest Region, the production efficiencies show downward trend. The efficiencies in the Southwest Forest Region and South Forest Region have a tendency of inversed “U”-shape with the change of time. The average efficiency of the South Forest Region is the highest, which is 1.036, followed by the efficiency of the Northeast Forest Region, which is 1.020. The Malmquist index does not show σ convergence in the four forest regions of China, and there is a phenomenon of absolute β divergence, which means that the differences of the absolute values and the growth rates of the forestry production efficiencies in the four forest regions do not reduce with time.
    References | Related Articles | Metrics
    Analyze on the Spatial-temporal Pattern and Influence Factors of China’s per Capita Household Carbon Emissions
    LIU Li-na, QU Jian-sheng, HUANG Yu-sheng, WANG Li, ZENG Jing-jing, BIAN Yue
    2016, 31 (8):  1364-1377.  doi: 10.11849/zrzyxb.20150905
    Abstract ( )   HTML ( )   PDF (4139KB) ( )   Save

    This paper calculates per capita household carbon emissions (HCEs) based on IPCC’s reference approach and Input-output analysis (IOA) of different categories of carbon emissions in China from 1997 to 2012. Its driving factors are also analyzed with the Spatial Error Model (SEM) and the Spatial Lag Model (SLM). The main purpose of this work is to emphasize the characteristics of household carbon emissions based on temporal scale and spatial scale. The results show that: 1) Based on different carbon sources, HCEs can be divided into direct and indirect emissions; based on different human needs, HCEs can be classified as basic and development emissions; based on different consumers’ behaviors, HCEs can be divided into transportation, housing, food, goods and service emissions. 2) At the time scale, both direct and indirect per capita HCEs, basic and development per capita HCEs, and each item of per capita HCEs based on behaviors exhibit the increasing tendency. 3) From the spatial perspective, there is a common pattern in spatial distributions of per capita HCEs. The cluster effect of per capita HCEs is stable. 4) From the space point of view, the per capita HCEs in China shows a decreasing tendency from east to west in 2012. 5) Based on the spatial analysis model, the proportion of basic HCEs per capita in the whole is the main driving factor. Meanwhile, per capita income and per capita GDP are also affecting per capita HCEs. On the basis of analyzing the spatial-temporal patterns and driving factors of per capita household carbon emissions, we provide scientific evidences and put forward effective suggestions for carbon emissions reduction measures and policies.

    References | Related Articles | Metrics
    Research on CO2 Emission Factors of Cement Production by the Measurement of Carbonate
    WEI Jun-xiao, GENG Yuan-bo, ZHAO Jian-an, WANG Song, MU Yue
    2016, 31 (8):  1378-1387.  doi: 10.11849/zrzyxb.20150951
    Abstract ( )   HTML ( )   PDF (1844KB) ( )   Save
    In order to optimize the calculation of cement CO2 emission factors, we analyzed and calculated the clinker and cement CO2 emission factors based on raw material carbonate method and the classification of emissions. The emissions are divided into the process-related emissions and the combustion-related emissions of NSP kilns, and the inorganic carbon emissions and the organic carbon emissions of shaft kilns. Based on the sampled test data, the process-related emission factors of NSP kilns are 520.00 kg CO2/tcl, the combustion-related emission factors are about 288.06 kg CO2/tcl, and the clinker CO2 emission factors are 808.06 kg CO2/tcl. For the shaft kiln, the inorganic carbon emission factors are 504.18 kg CO2/tcl, organic carbon emission factors are 343.67 kg CO2/tcl, and clinker carbon emission factors are 847.85 kg CO2/tcl. Due to the popularity of NSP kilns and cogeneration technology, and the decline of clinker-to-cement ratio, China’s cement CO2 emission factor has decreased year by year. From 2001 to 2012, China’s cement CO2 emission factors decreased from 767.13 kg CO2/tce to 550.80 kg CO2/tce, respectively. Process-related emissions, combustion-related emissions and electricity-related emissions account for 58.57%, 29.79% and 11.64% approximately in the cement CO2 emission.
    References | Related Articles | Metrics
    Assessment on Low-carbon Effects of Hydropower Development in Tibet, China
    ZHAO Wei, SHEN Wei-shou, LI Hai-dong
    2016, 31 (8):  1388-1398.  doi: 10.11849/zrzyxb.20150928
    Abstract ( )   HTML ( )   PDF (1334KB) ( )   Save
    Hydropower development and outward transmission in Tibet play a vital role in optimization of energy resource configuration and reduction of CO2 emission in China. The low-carbon effects of hydropower development in Tibet were assessed, and fossil fuel consumption reduction and CO2 reduction achieved by hydropower development in Tibet were analyzed based on net coal consumption rate, CO2 emission coefficient and its dynamic change of fossil-fired power generation in different power grids. The results show that: 1) The fossil fuel consumption reduction and the CO2 reduction achieved by hydropower development in Tibet have significant variations. During the period from 2006 to 2012, the fossil fuel consumption reduction and the CO2 reduction achieved by hydropower development in Tibet were the most in 2011. 2) The fossil fuel consumption reductions achieved by hydropower development in Tibet were different significantly with different net coal consumption rates of fossil-fired power generation. The fossil fuel consumption reduction achieved by hydropower development according to net coal consumption rate of fossil-fired power generation in Central China power grid (CCPG) was the most, the fossil fuel consumption reduction according to net coal consumption rate of fossil-fired power generation in Northwest China power grid (NCPG) and Tibet power grid (TPG) took the second and the third place respectively, and the fossil fuel consumption reduction according to net coal consumption rate of fossil-fired power generation in national power grid (NPG) was the least. 3) According to different CO2 emission levels of fossil-fired power generation, the CO2 reductions achieved by hydropower development in Tibet were also different. Among them, the CO2 reduction achieved by hydropower development according to CO2 emission level of fossil-fired power generation in TPG was the most, the CO2 reduction of hydropower development according to CO2 emission level of fossil-fired power generation in NCPG and CCPG took the second and the third place respectively. 4) The fossil fuel consumption reduction potential and the CO2 reduction potential achieved by hydropower development in Tibet were outstanding. According to net coal consumption rates of fossil-fired power generation in NCPG, CCPG, TPG and NPG, the fossil fuel consumption reductions achieved by hydropower development in Tibet in 2030 would be more than 75% of total fossil fuel consumption (1.379×108 tec) of fossil-fired power generation in NCPG in 2012. Among the CO2 reduction potentials according to different CO2 emission levels, the CO2 reduction achieved by hydropower development in Tibet according to CO2 emission level of fossil-fired power generation in CCPG would be the least, but more than the carbon dioxide emissions of fossil fuel consumption in Argentina, Pakistan, Vietnam and other countries in 2013.
    References | Related Articles | Metrics
    Changes of Organic Carbon and Readily Oxidizable Carbon in Deep Soil at Different Developmental Stages of Artificial Pinus tabulaeformis Plantation and the Impact Factors
    QIU Tian-tian, LIU Guo-bin, WANG Guo-liang, SUN Li-peng, YAO Xu
    2016, 31 (8):  1399-1409.  doi: 10.11849/zrzyxb.20150917
    Abstract ( )   HTML ( )   PDF (2226KB) ( )   Save
    It is not clear how plantation affect the soil organic carbon (SOC) in deep soil for terrestrial ecosystem. Based on space for time method, we studied the effect of Pinus tabulaeformis plantations at three developmental stages (young forest, middle age forest and mature forest) on the soil organic carbon (SOC) and soil readily oxidizable carbon (ROC) in 0-200 cm soil profile. The results showed that SOC content and storage significantly increased in soils with different developmental stages of Pinus tabulaeformis plantation compared with abandoned cropland in 0-200 cm profile. In the 0-100 cm soil layer, average SOC content of mature forest, middle age forest and young forest were 2.03, 1.85 and 1.59 times more than that in abandoned cropland, respectively. SOC storage in shallow and deep soil layers contributed 61.0%-69.8% and 30.2%-39.0% to total SOC storage in the whole profile (0-200 cm) at all of the investigated developmental stages. SOC storage in shallow soil layer varied significantly among different developmental stages, however, no obvious difference of SOC storage in deep soil layer was observed at all developmental stages. Compared to that in abandoned cropland, the ROC storage in soils of young forest, middle age forest and mature forest increased 54.8%, 82.0% and 91.6% in shallow soil layer and 32.4%, 40.9% and 58.1% in deep soil layer, respectively. ROC storage in deep soil layer contributed 31.2%-33.3% to total ROC storage in the whole profile (0-200 cm) at all developmental stages. SOC and ROC content in shallow soil layer were influenced by a number of factors, furthermore, ROC content in deep soil showed significant correlations with the plant height, root biomass, litter thickness and litter biomass. In conclusion, construction of artificial forest may significantly improve the soil carbon pool in both shallow and deep soil profiles.
    References | Related Articles | Metrics
    Regional Environmental Carrying Capacity for Livestock and Poultry Breeding Based on Planting-breeding Balance in Hangzhou City
    QIU Le-feng, LONG Wen-li, FANG Hao, HU Wei
    2016, 31 (8):  1410-1419.  doi: 10.11849/zrzyxb.20151101
    Abstract ( )   HTML ( )   PDF (2594KB) ( )   Save
    Taking available nitrogen and phosphorus in soil, and annual statistical data of planting and breeding as data sources, and using modified nutrient-balance method, the environmental carrying capacity and pollution risk of livestock and poultry breeding in Hangzhou City was explored. Firstly, it is found that the amount of nitrogen and phosphorus consumption of main crops in Hangzhou were 39 886.4 and 21 874.1 t in 2014. Vegetable, rice, fruit and beans consumed 11 879.7, 8 588.2, 5 255.0 and 4 641.6 t of nitrogen, respectively. Meanwhile, vegetable, rice and fruit also consumed 10 394.8, 4 480.8 and 2 189.6 t of phosphorus, respectively. Secondly, the strongest counties of soil nitrogen and phosphorus supply were Lin’an (86.6 kg/hm2 for nitrogen) and the downtown area (60.6 kg/hm2 for phosphorus), while the weakest one was Tonglu County (77.0 kg/hm2 for nitrogen and 59.2 kg/hm2 for phosphorus). Thirdly, during 2014, the environmental carrying capacities of districts in Hangzhou ranged from 1.48 to 35.59 heads/hm2, and 1.01 to 39.79 heads/hm2 when calculated on the basis of nitrogen and phosphorus, respectively. According to the environmental carrying capacity of livestock and poultry breeding, all the counties of Hangzhou City could be divided into three levels. Fuyang was on the highest level with carrying capacity of 35.59 (based on nitrogen) and 39.79 head/hm2 (based on phosphorus). Yuhang, Xiaoshan, and Jiande were on the second level with carrying capacities ranging from 20 to 30 head/hm2. Tonglu, Lin’an, Chun’an and the downtown area were on the lowest level with carrying capacities all below 10 head/hm2. Fourthly, the pollution risk indices in livestock manure ranged from 0.19 to 8.05 (based on nitrogen) and 0.14 to 11.68 (based on phosphorus). These results indicated that the pollution risk of livestock manure in Hangzhou was generally low. However, the pollution risk in each district was significantly different. Environmental carrying capacities of the downtown area and counties of Lin’an, Chun’an and Tonglu were severely overburdened, while Fuyang, Yuhang, Xiaoshan and Jiande had not exceeded their environmental carrying capacity. Overall, the areas with high pollution risk of livestock manure needed to reduce the scale of breeding urgently and transfer the redundant manure to surrounding counties that still have potential carrying capacity. Besides, regions having rich woodland resource also can take the wood land as disposal site to load livestock manure. As a result, more detailed data is in urgent needed to achieve more scientific and accurate results so as to provide scientific basis for layout planning and pollution regulation of livestock and poultry breeding industry in Hangzhou.
    References | Related Articles | Metrics
    Estimating Population Parameters and Abundance of Coreius heterodon in Jiangjin Section of the Upper Yangtze River
    LIU Hong-yan, XIONG Fei, DUAN Xin-bin, LIU Shao-ping, CHEN Da-qing
    2016, 31 (8):  1420-1428.  doi: 10.11849/zrzyxb.20151067
    Abstract ( )   HTML ( )   PDF (2937KB) ( )   Save
    Coreius heterodon, a representative semi-migratory species, is one of the important economic fish species in the main channel of the Yangtze River. However, its resources has been in serious degradation. To understand its population dynamics after the Three Gorges Reservoir and before the Xiangjiaba and Xiluodu reservoirs were impounded, we used FAO-ICLARM Stock Assessment Tools based on length-frequency data to estimate the growth and mortality parameters, and population abundance of C. heterodon based on surveys in Jiangjin section conducted in 2007-2009. The fishes ranged from 125 to 530 mm in length and 24 to 2 250 g in weight, with an average length of 228.7 ± 56.6 mm and an average weight of 206.4 ± 251.9 g. The length group of 150-270 mm dominated the catches (80.4% of the total number). The length-weight relationship of C. heterodon fit well with a power function, W = 7.63×10-6 L3.10 (R2 = 0.97, P < 0.01, n = 280). Asymptotic length (L) and growth constant (k) were estimated using length frequency data to be 630.0 mm and 0.23 a-1, respectively. Natural mortality was estimated to be 0.46 using the empirical formula proposed by Pauly. The total mortality was estimated using a length-converted catch curve analysis to be 1.82. The minimum catchable size was 170.7 mm, and the exploitation rate observed was 0.75, which was higher than the estimated maximum exploitation rate (0.50). Population abundance of C. heterodon in Jiangjin section was estimated by length-structured virtual population analyses to be 2 820 ind·km-1 (2.63 t·km-1) in 2007, 3 035 ind· km-1 (4.71 t· km-1) in 2008, and 8 130 ind·km-1 (16.56 t· km-1) in 2009, respectively, with an study average of 4 661 ind· km-1 (7.96 t· km-1). In view of the rapidly declined resources of C. heterodon in the Yangtze River, especially in the lower reaches, we suggest to stop exploiting the resources immediately. We also suggest Jiangjin section should be considered as the prior region for population conservation and habitat restoration of C. heterodon.
    References | Related Articles | Metrics
Share: