2014 Vol. 0, No. 2
Display Method:
2014, 0(2): 137-146.
doi: 10.1007/s11769-013-0650-5
Abstract:
A continuous three-year observation (from May 2008 to April 2011) was conducted to characterize the spatial variation of dissolved inorganic nitrogen (DIN) deposition at eight main forest ecosystems along the north-south transect of eastern China (NSTEC). The results show that both throughfall DIN deposition and bulk DIN deposition increase from north to south along the NSTEC. Throughfall DIN deposition varies greatly from 2.7 kg N/(ha·yr) to 33.0 kg N/(ha·yr), with an average of 10.6 kg N/(ha·yr), and bulk DIN deposition ranges from 4.1 kg N/(ha·yr) to 25.4 kg N/(ha·yr), with an average of 9.8 kg N/(ha·yr). NH4+-N is the dominant form of DIN deposition at most sampling sites. Additionally, the spatial variation of DIN deposition is controlled mainly by precipitation. Moreover, in the northern part of the NSTEC, bulk DIN deposition is 17% higher than throughfall DIN deposition, whereas the trend is opposite in the southern part of the NSTEC. The results demonstrate that DIN deposition would likely threaten the forest ecosystems along the NSTEC, compared with the critical loads (CL) of N deposition, and DIN deposition in this region is mostly controlled by agricultural activities rather than industrial activities or transportation.
A continuous three-year observation (from May 2008 to April 2011) was conducted to characterize the spatial variation of dissolved inorganic nitrogen (DIN) deposition at eight main forest ecosystems along the north-south transect of eastern China (NSTEC). The results show that both throughfall DIN deposition and bulk DIN deposition increase from north to south along the NSTEC. Throughfall DIN deposition varies greatly from 2.7 kg N/(ha·yr) to 33.0 kg N/(ha·yr), with an average of 10.6 kg N/(ha·yr), and bulk DIN deposition ranges from 4.1 kg N/(ha·yr) to 25.4 kg N/(ha·yr), with an average of 9.8 kg N/(ha·yr). NH4+-N is the dominant form of DIN deposition at most sampling sites. Additionally, the spatial variation of DIN deposition is controlled mainly by precipitation. Moreover, in the northern part of the NSTEC, bulk DIN deposition is 17% higher than throughfall DIN deposition, whereas the trend is opposite in the southern part of the NSTEC. The results demonstrate that DIN deposition would likely threaten the forest ecosystems along the NSTEC, compared with the critical loads (CL) of N deposition, and DIN deposition in this region is mostly controlled by agricultural activities rather than industrial activities or transportation.
2014, 0(2): 147-162.
doi: 10.1007/s11769-013-0620-y
Abstract:
The soil and water conservation practices of ecological restoration (ER), fish scale pit (FP), furrow and ridge tillage across the slope (FR), shrub strips (SS), and vegetation-covered ridge (VR) are characteristic of the Jixing small watershed of the low mountain and hilly region of Jilin Province, Northeast China. This study aims to elucidate the effects of soil and water conservation practices on soil conditions after the short-term implementation of practices. Soil samples were collected from five soil and water conservation sites (ER, FP, FR, SS, and VR) and two controls (BL and CT) to investigate their properties. To evaluate the influence of soil and water conservation practices on soil quality, an integrated quantitative index, soil quality index (QI), was developed to compare the soil quality under the different soil and water conservation practices. The results show that not all soil and water conservation practices can improve the soil conditions and not all soil properties, especially soil organic carbon (SOC), can be recovered under soil and water conservation practice in short-term. Moreover, the QI in the five soil and water conservation practices and two controls was in the following order: ER > VR > BL > FR > CT > SS > FP. ER exhibited a higher soil quality value on a slope scale. In the low mountain and hilly region of Northeast China, ER is a better choice than the conversion of farmlands to planted grasslands and woodlands early in the soil and water conservation program.
The soil and water conservation practices of ecological restoration (ER), fish scale pit (FP), furrow and ridge tillage across the slope (FR), shrub strips (SS), and vegetation-covered ridge (VR) are characteristic of the Jixing small watershed of the low mountain and hilly region of Jilin Province, Northeast China. This study aims to elucidate the effects of soil and water conservation practices on soil conditions after the short-term implementation of practices. Soil samples were collected from five soil and water conservation sites (ER, FP, FR, SS, and VR) and two controls (BL and CT) to investigate their properties. To evaluate the influence of soil and water conservation practices on soil quality, an integrated quantitative index, soil quality index (QI), was developed to compare the soil quality under the different soil and water conservation practices. The results show that not all soil and water conservation practices can improve the soil conditions and not all soil properties, especially soil organic carbon (SOC), can be recovered under soil and water conservation practice in short-term. Moreover, the QI in the five soil and water conservation practices and two controls was in the following order: ER > VR > BL > FR > CT > SS > FP. ER exhibited a higher soil quality value on a slope scale. In the low mountain and hilly region of Northeast China, ER is a better choice than the conversion of farmlands to planted grasslands and woodlands early in the soil and water conservation program.
2014, 0(2): 163-179.
doi: 10.1007/s11769-013-0630-9
Abstract:
In karst regions, the spatial heterogeneity of soil mineral oxides and environmental variables is still not clear. We investigated the spatial heterogeneity of SiO2, Al2O3, Fe2O3, CaO, MgO, P2O5, K2O, and MnO contents in the soils of slope land, plantation forest, secondary forest, and primary forest, as well as their relationships with environmental variables in a karst region of Southwest China. Geostatistics, principal component analysis (PCA), and canonical correlation analysis (CCA) were applied to analyze the field data. The results show that SiO2 was the predominant mineral in the soils (45.02%-67.33%), followed by Al2O3 and Fe2O3. Most soil mineral oxide components had a strong spatial dependence, except for CaO, MgO, and P2O5 in the plantation forest, MgO and P2O5 in the secondary forest, and CaO in the slope land. Dimensionality reduction in PCA was not appropriate due to the strong spatial heterogeneity in the ecosystems. Soil mineral oxide components, the main factors in all ecosystems, had greater influences on vegetation than those of conventional soil properties. There were close relationships between soil mineral oxide components and vegetation, topography, and conventional soil properties. Mineral oxide components affected species diversity, organic matter and nitrogen levels.
In karst regions, the spatial heterogeneity of soil mineral oxides and environmental variables is still not clear. We investigated the spatial heterogeneity of SiO2, Al2O3, Fe2O3, CaO, MgO, P2O5, K2O, and MnO contents in the soils of slope land, plantation forest, secondary forest, and primary forest, as well as their relationships with environmental variables in a karst region of Southwest China. Geostatistics, principal component analysis (PCA), and canonical correlation analysis (CCA) were applied to analyze the field data. The results show that SiO2 was the predominant mineral in the soils (45.02%-67.33%), followed by Al2O3 and Fe2O3. Most soil mineral oxide components had a strong spatial dependence, except for CaO, MgO, and P2O5 in the plantation forest, MgO and P2O5 in the secondary forest, and CaO in the slope land. Dimensionality reduction in PCA was not appropriate due to the strong spatial heterogeneity in the ecosystems. Soil mineral oxide components, the main factors in all ecosystems, had greater influences on vegetation than those of conventional soil properties. There were close relationships between soil mineral oxide components and vegetation, topography, and conventional soil properties. Mineral oxide components affected species diversity, organic matter and nitrogen levels.
2014, 0(2): 180-190.
doi: 10.1007/s11769-014-0665-6
Abstract:
Radionuclide dating techniques characterized by 137Cs and 210Pbex have recently been applied in the study of lake sediments around the world. In this study, a chronological series of sediment cores was established based on 137Cs and 210Pbex analyses along with the evaluation of sediment properties, such as particle size distribution, total organic carbon (TOC), carbonate content, and acid-insoluble residue, to study sediment accumulation rates, sediment sources, and responses to human activities in the Jiuzhaigou National Nature Reserve in southwestern China. In terms of the particle size distribution of sediments, silt content was the highest, and clay and sand contents were relatively low. The sediments displayed high TOC contents because of the significant amounts of vegetation grown in the lakes. The carbonate content was also high due to the overall geological background of carbonates in Jiuzhaigou. Carbonate content tended to decline from top to bottom in the sediment cores, whereas the acid-insoluble residue tended to increase. These results suggested that the depth variation of the environmental parameters of the sediments in two lakes in Jiuzhaigou would correspond to each other. The results indicated that the sediment rate of Jiuzhaigou was generally high with strong siltation, indicating that serious soil loss was induced by intensive human activities in the basin over the past decades. The increases in the mass accumulation rate, contents of acid-insoluble residue, and mean particle size during the periods of 1840-1900s, late 1930s-early 1950s, 1966-1978, and 2003-2006 revealed the occurrence of severe soil and water loss as a result of extensive agricultural expansion, large-scale deforestation, and road construction in Jiuzhaigou. The deposition rate and the properties of lacustrine sediments could reflect the significant impact of human activities on lake sedimentation during Jiuzhaigou’s history.
Radionuclide dating techniques characterized by 137Cs and 210Pbex have recently been applied in the study of lake sediments around the world. In this study, a chronological series of sediment cores was established based on 137Cs and 210Pbex analyses along with the evaluation of sediment properties, such as particle size distribution, total organic carbon (TOC), carbonate content, and acid-insoluble residue, to study sediment accumulation rates, sediment sources, and responses to human activities in the Jiuzhaigou National Nature Reserve in southwestern China. In terms of the particle size distribution of sediments, silt content was the highest, and clay and sand contents were relatively low. The sediments displayed high TOC contents because of the significant amounts of vegetation grown in the lakes. The carbonate content was also high due to the overall geological background of carbonates in Jiuzhaigou. Carbonate content tended to decline from top to bottom in the sediment cores, whereas the acid-insoluble residue tended to increase. These results suggested that the depth variation of the environmental parameters of the sediments in two lakes in Jiuzhaigou would correspond to each other. The results indicated that the sediment rate of Jiuzhaigou was generally high with strong siltation, indicating that serious soil loss was induced by intensive human activities in the basin over the past decades. The increases in the mass accumulation rate, contents of acid-insoluble residue, and mean particle size during the periods of 1840-1900s, late 1930s-early 1950s, 1966-1978, and 2003-2006 revealed the occurrence of severe soil and water loss as a result of extensive agricultural expansion, large-scale deforestation, and road construction in Jiuzhaigou. The deposition rate and the properties of lacustrine sediments could reflect the significant impact of human activities on lake sedimentation during Jiuzhaigou’s history.
2014, 0(2): 191-204.
doi: 10.1007/s11769-013-0631-8
Abstract:
This study used spatial autoregression (SAR) model and geographically weighted regression (GWR) model to model the spatial patterns of farmland density and its temporal change in Gucheng County, Hubei Province, China in 1999 and 2009, and discussed the difference between global and local spatial autocorrelations in terms of spatial heterogeneity and non-stationarity. Results showed that strong spatial positive correlations existed in the spatial distributions of farmland density, its temporal change and the driving factors, and the coefficients of spatial autocorrelations decreased as the spatial lag distance increased. SAR models revealed the global spatial relations between dependent and independent variables, while the GWR model showed the spatially varying fitting degree and local weighting coefficients of driving factors and farmland indices (i.e., farmland density and temporal change). The GWR model has smooth process when constructing the farmland spatial model. The coefficients of GWR model can show the accurate influence degrees of different driving factors on the farmland at different geographical locations. The performance indices of GWR model showed that GWR model produced more accurate simulation results than other models at different times, and the improvement precision of GWR model was obvious. The global and local farmland models used in this study showed different characteristics in the spatial distributions of farmland indices at different scales, which may provide the theoretical basis for farmland protection from the influence of different driving factors.
This study used spatial autoregression (SAR) model and geographically weighted regression (GWR) model to model the spatial patterns of farmland density and its temporal change in Gucheng County, Hubei Province, China in 1999 and 2009, and discussed the difference between global and local spatial autocorrelations in terms of spatial heterogeneity and non-stationarity. Results showed that strong spatial positive correlations existed in the spatial distributions of farmland density, its temporal change and the driving factors, and the coefficients of spatial autocorrelations decreased as the spatial lag distance increased. SAR models revealed the global spatial relations between dependent and independent variables, while the GWR model showed the spatially varying fitting degree and local weighting coefficients of driving factors and farmland indices (i.e., farmland density and temporal change). The GWR model has smooth process when constructing the farmland spatial model. The coefficients of GWR model can show the accurate influence degrees of different driving factors on the farmland at different geographical locations. The performance indices of GWR model showed that GWR model produced more accurate simulation results than other models at different times, and the improvement precision of GWR model was obvious. The global and local farmland models used in this study showed different characteristics in the spatial distributions of farmland indices at different scales, which may provide the theoretical basis for farmland protection from the influence of different driving factors.
2014, 0(2): 205-219.
doi: 10.1007/s11769-013-0637-2
Abstract:
Double- and triple-cropping in a year have played a very important role in meeting the rising need for food in China. However, the intensified agricultural practices have significantly altered biogeochemical cycles and soil quality. Understanding and mapping cropping intensity in China′s agricultural systems are therefore necessary to better estimate carbon, nitrogen and water fluxes within agro-ecosystems on the national scale. In this study, we investigated the spatial pattern of crop calendar and multiple cropping rotations in China using phenological records from 394 agro-meteorological stations (AMSs) across China. The results from the analysis of in situ field observations were used to develop a new algorithm that identifies the spatial distribution of multiple cropping in China from moderate resolution imaging spectroradiometer (MODIS) time series data with a 500 m spatial resolution and an 8-day temporal resolution. According to the MODIS-derived multiple cropping distribution in 2002, the proportion of cropland cultivated with multiple crops reached 34% in China. Double-cropping accounted for approximately 94.6% and triple-cropping for 5.4%. The results demonstrat that MODIS EVI (Enhanced Vegetation Index) time series data have the capability and potential to delineate the dynamics of double- and triple-cropping practices. The resultant multiple cropping map could be used to evaluate the impacts of agricultural intensification on biogeochemical cycles.
Double- and triple-cropping in a year have played a very important role in meeting the rising need for food in China. However, the intensified agricultural practices have significantly altered biogeochemical cycles and soil quality. Understanding and mapping cropping intensity in China′s agricultural systems are therefore necessary to better estimate carbon, nitrogen and water fluxes within agro-ecosystems on the national scale. In this study, we investigated the spatial pattern of crop calendar and multiple cropping rotations in China using phenological records from 394 agro-meteorological stations (AMSs) across China. The results from the analysis of in situ field observations were used to develop a new algorithm that identifies the spatial distribution of multiple cropping in China from moderate resolution imaging spectroradiometer (MODIS) time series data with a 500 m spatial resolution and an 8-day temporal resolution. According to the MODIS-derived multiple cropping distribution in 2002, the proportion of cropland cultivated with multiple crops reached 34% in China. Double-cropping accounted for approximately 94.6% and triple-cropping for 5.4%. The results demonstrat that MODIS EVI (Enhanced Vegetation Index) time series data have the capability and potential to delineate the dynamics of double- and triple-cropping practices. The resultant multiple cropping map could be used to evaluate the impacts of agricultural intensification on biogeochemical cycles.
2014, 0(2): 220-230.
doi: 10.1007/s11769-013-0644-3
Abstract:
This paper uses the Global Trade Analysis Project (version 7) database to calculate embodied CO2 emissions in bilateral trade between China and other countries (regions) based on input-output methods. The sources and flows of embodied CO2 emissions in import and export trade of China are analyzed. Results show that the flows of embodied CO2 emissions in export trade are highly concentrated. The main flows to the United States (US) and Japan account for 1/4 and 1/7 of the total CO2 emissions in export trade, respectively. Concentrated flows of total exports and small differences in export structure are the main reasons for the highly concentrated export trade. The sources of embodied CO2 emissions in import trade have relatively low concentration. Taiwan Province of China, Hong Kong Special Administrative Region of China, US, Russia, Republic of Korea, and Japan account for around 7.72%-12.67% of the total embodied CO2 emissions in import trade. The relative dispersion of import sources, the impact of the import structure, and the level of production technology in importing countries caused low concentration of CO2 emissions in import trade. Overall, the embodied CO2 emissions in the export trade of China are higher than those in import trade. As a result, production-based CO2 emissions are higher than consumption-based CO2 emissions. The difference of 8.96 × 108 t of CO2, which comes mainly from the US, Japan, Germany, and the United Kingdom, accounts for 58.70% of the total difference. Some suggestions, such as improving energy efficiency, alerting high carbon-intensive industries transfer, expanding the market for sharing risks, and prompting the accounting system of consumption-based CO2 emissions, are proposed based on the results.
This paper uses the Global Trade Analysis Project (version 7) database to calculate embodied CO2 emissions in bilateral trade between China and other countries (regions) based on input-output methods. The sources and flows of embodied CO2 emissions in import and export trade of China are analyzed. Results show that the flows of embodied CO2 emissions in export trade are highly concentrated. The main flows to the United States (US) and Japan account for 1/4 and 1/7 of the total CO2 emissions in export trade, respectively. Concentrated flows of total exports and small differences in export structure are the main reasons for the highly concentrated export trade. The sources of embodied CO2 emissions in import trade have relatively low concentration. Taiwan Province of China, Hong Kong Special Administrative Region of China, US, Russia, Republic of Korea, and Japan account for around 7.72%-12.67% of the total embodied CO2 emissions in import trade. The relative dispersion of import sources, the impact of the import structure, and the level of production technology in importing countries caused low concentration of CO2 emissions in import trade. Overall, the embodied CO2 emissions in the export trade of China are higher than those in import trade. As a result, production-based CO2 emissions are higher than consumption-based CO2 emissions. The difference of 8.96 × 108 t of CO2, which comes mainly from the US, Japan, Germany, and the United Kingdom, accounts for 58.70% of the total difference. Some suggestions, such as improving energy efficiency, alerting high carbon-intensive industries transfer, expanding the market for sharing risks, and prompting the accounting system of consumption-based CO2 emissions, are proposed based on the results.
2014, 0(2): 231-244.
doi: 10.1007/s11769-013-0645-2
Abstract:
Since the reform and opening-up program started in 1978, the level of urbanization has increased rapidly in China. Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas. In this study, ArcGIS 10, ENVI 4.5, and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656 Chinese cities from 1992 to 2010. Firstly, an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System (DMSP_OLS) nighttime light data. This improved algorithm has the advantages of high accuracy and speed. Secondly, a mathematical model (Human impacts (HI)) was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation Index (NDVI) and Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI. HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects. The results were analyzed from four aspects: the size of cities (metropolises, large cities, medium-sized cities, and small cities), large regions (the eastern, central, western, and northeastern China), administrative divisions of China (provinces, autonomous regions, and municipalities) and vegetation zones (humid and semi-humid forest zone, semi-arid steppe zone, and arid desert zone). Finally, we discussed how human factors impacted on vegetation changes in the built-up areas. We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas. The negative human impacts followed an inverted ‘U’ shape, first rising and then falling with increase of urban scales. China’s national policies, social and economic development affected vegetation changes in the built-up areas. The findings can provide a scientific basis for municipal planning departments, a decision-making reference for government, and scientific guidance for sustainable development in China.
Since the reform and opening-up program started in 1978, the level of urbanization has increased rapidly in China. Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas. In this study, ArcGIS 10, ENVI 4.5, and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656 Chinese cities from 1992 to 2010. Firstly, an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System (DMSP_OLS) nighttime light data. This improved algorithm has the advantages of high accuracy and speed. Secondly, a mathematical model (Human impacts (HI)) was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation Index (NDVI) and Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI. HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects. The results were analyzed from four aspects: the size of cities (metropolises, large cities, medium-sized cities, and small cities), large regions (the eastern, central, western, and northeastern China), administrative divisions of China (provinces, autonomous regions, and municipalities) and vegetation zones (humid and semi-humid forest zone, semi-arid steppe zone, and arid desert zone). Finally, we discussed how human factors impacted on vegetation changes in the built-up areas. We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas. The negative human impacts followed an inverted ‘U’ shape, first rising and then falling with increase of urban scales. China’s national policies, social and economic development affected vegetation changes in the built-up areas. The findings can provide a scientific basis for municipal planning departments, a decision-making reference for government, and scientific guidance for sustainable development in China.
2014, 0(2): 245-257.
doi: 10.1007/s11769-013-0619-4
Abstract:
To shed light on the general patterns and trends in urban sprawl research, and to provide reference for future study, bibliometric analysis and refined analysis are conducted for publications in this area from 1991 to 2011. The general publication output, the global geographical distribution of the authors, the funding and institutions involved, the research areas, and the source titles are analyzed and discussed. Scholars in the United States and China have produced most of the documents in urban sprawl and these two countries are also the largest contributors in terms of funding and institutions. ‘Environmental Sciences & Ecology’, ‘Urban Studies’, and ‘Geography’ are the most common research areas, and the journal titled Urban Studies has contributed the most articles. Furthermore, the refined analyses on the 500 top-cited and most relevant publications have revealed that research on urban sprawl is closely associated with the categories of ‘Urban form and development’, ‘Land use/land development’ and ‘environment/ecology/biology’. Conclusions are made with respect to the basic paradigm of research on urban sprawl. The multi-disciplinary research into urban sprawl are expected to be more diversified and integrated.
To shed light on the general patterns and trends in urban sprawl research, and to provide reference for future study, bibliometric analysis and refined analysis are conducted for publications in this area from 1991 to 2011. The general publication output, the global geographical distribution of the authors, the funding and institutions involved, the research areas, and the source titles are analyzed and discussed. Scholars in the United States and China have produced most of the documents in urban sprawl and these two countries are also the largest contributors in terms of funding and institutions. ‘Environmental Sciences & Ecology’, ‘Urban Studies’, and ‘Geography’ are the most common research areas, and the journal titled Urban Studies has contributed the most articles. Furthermore, the refined analyses on the 500 top-cited and most relevant publications have revealed that research on urban sprawl is closely associated with the categories of ‘Urban form and development’, ‘Land use/land development’ and ‘environment/ecology/biology’. Conclusions are made with respect to the basic paradigm of research on urban sprawl. The multi-disciplinary research into urban sprawl are expected to be more diversified and integrated.
2014, 0(2): 258-268.
doi: 10.1007/s11769-013-0617-6
Abstract:
This paper falls into the broad area of economic geography and economics of creativity, and it presents an alternative approach to explain why total factor productivity (TFP) growth is different across China′s regions. It establishes an empirical model to estimate the spatial agglomeration effects of creative industries on regional TFP growth, using China’s provincial panel data during the period of 2003 to 2010. We found that the creative industries agglomeration (CIA) has significant and positive impact on regional TFP growth. The result also implies that the CIA can facilitate regional TFP growth through promoting regional innovation instead of improving regional efficiency. Therefore, we argue that policy makers should take some measures to retain and establish more creative zones.
This paper falls into the broad area of economic geography and economics of creativity, and it presents an alternative approach to explain why total factor productivity (TFP) growth is different across China′s regions. It establishes an empirical model to estimate the spatial agglomeration effects of creative industries on regional TFP growth, using China’s provincial panel data during the period of 2003 to 2010. We found that the creative industries agglomeration (CIA) has significant and positive impact on regional TFP growth. The result also implies that the CIA can facilitate regional TFP growth through promoting regional innovation instead of improving regional efficiency. Therefore, we argue that policy makers should take some measures to retain and establish more creative zones.
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