Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid areas.In this study,the spatial autocorrelation method and the spatial computation model were used...Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid areas.In this study,the spatial autocorrelation method and the spatial computation model were used to investigate the spatial impacts of mineral resources excavation and processing on comprehensive level of urbanization in the Tarim River Basin,Xinjiang,China for the years of 2000,2006 and 2008.The results are as follows:1)There was a spatial correlation of the development of mineral resources industry and the comprehensive level of urbanization in 2006 and 2008,with the spatial concentration trend rising significantly in 2006 and decreasing in 2008.2)The patterns of local spatial concentration of mineral resources industry and of the comprehensive level of urbanization were relatively stable,and the two patterns showed signs of spatial correlationship.The higher was the degree of the concentration of mineral resources industry,the stronger was its impact on the spatial clustering of urbanization.3)In 2000, mineral resources excavation and processing had a significant positive impact on the comprehensive level of urbanization in the region but not in its adjacent regions.However,in 2008,mineral resources excavation and processing significantly raised the comprehensive level of urbanization not only in the region but also in its neighboring regions.This research demonstrates that the development of mineral resources industry can strongly affect the trends and spatial patterns of urbanization.展开更多
Characteristics of seismic activity before the M5. 1 earthquake in Wen＇an, Hebei Province on July 4, 2006 are analyzed by relocation of small earthquakes in the China＇s capital area, and some results are obtained as...Characteristics of seismic activity before the M5. 1 earthquake in Wen＇an, Hebei Province on July 4, 2006 are analyzed by relocation of small earthquakes in the China＇s capital area, and some results are obtained as follows：① The seismic activity of ML ≥ 3.0 in the middle part of the Hebei plain seismic belt displayed a feature of strengthening （ lasting 43 months） quiescence （17 months） five years before the Wen＇an earthquake. Simultaneously, the strain release curve showed a variation process of accelerating-flatting. ② A seismogenic gap in a three-dimensional space, located at the depth of 15km - 20km, with 70km long in latitude direction and 90km long in longitude orientation, was formed by M≥2.0 earthquakes four years prior to the Wen＇an earthquake. The initial rupture point of the Wen＇an earthquake is situated at the bottom of the gap. ③ The focal depths of earthquakes with ML ≥ 2. 0 in the middle part of the Hebei plain seismic belt gradually increased from 10km to 30kin during the period from April, 2003 to October, 2004. Meanwhile, the seismic activity obviously strengthened in the middle and lower crust （from 20km to 30km in depth）.展开更多
The migration of soil dissolved organic carbon(DOC) from terrestrial to aquatic environments has important impacts on the adjacent water quality and the transport of organic and inorganic contaminants.However,few stud...The migration of soil dissolved organic carbon(DOC) from terrestrial to aquatic environments has important impacts on the adjacent water quality and the transport of organic and inorganic contaminants.However,few studies have investigated the sources and properties of DOC in riparian zones.A total of 34 soil samples were collected across four riparian buffer zones(Zones A-D) on Chongming Island,China.The vertical distributions of soil organic carbon(SOC) and DOC,fluorescence excitation-emission matrix(EEM) spectra of DOC and the optical indices,including fluorescence index(FI),index of recent autochthonous contribution(BIX),and humification index(HIX),were measured across the riparian environment to investigate the sources and fluorescence properties of DOC.The results showed that SOC stored in the surface soil(0-30 cm) accounted for 40%of the total soil profile SOC.The DOC accumulated in Zones A-C,which accounted for 5%of the SOC.The fluorescence EEM spectra of DOC showed that DOC contained humic-like and protein-like substances,which were mainly derived from recent plant debris by microbes.A large amount of humic-like substances were sorbed to minerals in the surface soil(0-30 cm).In addition,the riparian topography and soil physico-chemical properties(pH,EC and moisture) dictated the transformation and transport of DOC.The results suggested that EEMs could reveal the source of DOC in riparian soil systems,and that optical indices were complementary tools that revealed the characteristics of soil DOC and provided supplemental evidence about DOC sources.展开更多
基金Under the auspices of Chinese Academy of Sciences Western Doctor Special Financial Aid(No.XBBS200812)National Natural Science Foundation of China(No.40601032)
文摘Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid areas.In this study,the spatial autocorrelation method and the spatial computation model were used to investigate the spatial impacts of mineral resources excavation and processing on comprehensive level of urbanization in the Tarim River Basin,Xinjiang,China for the years of 2000,2006 and 2008.The results are as follows:1)There was a spatial correlation of the development of mineral resources industry and the comprehensive level of urbanization in 2006 and 2008,with the spatial concentration trend rising significantly in 2006 and decreasing in 2008.2)The patterns of local spatial concentration of mineral resources industry and of the comprehensive level of urbanization were relatively stable,and the two patterns showed signs of spatial correlationship.The higher was the degree of the concentration of mineral resources industry,the stronger was its impact on the spatial clustering of urbanization.3)In 2000, mineral resources excavation and processing had a significant positive impact on the comprehensive level of urbanization in the region but not in its adjacent regions.However,in 2008,mineral resources excavation and processing significantly raised the comprehensive level of urbanization not only in the region but also in its neighboring regions.This research demonstrates that the development of mineral resources industry can strongly affect the trends and spatial patterns of urbanization.
基金sponsored by the National Key Technology R&D Program(2006BAC01B02-01-02),China
文摘Characteristics of seismic activity before the M5. 1 earthquake in Wen＇an, Hebei Province on July 4, 2006 are analyzed by relocation of small earthquakes in the China＇s capital area, and some results are obtained as follows：① The seismic activity of ML ≥ 3.0 in the middle part of the Hebei plain seismic belt displayed a feature of strengthening （ lasting 43 months） quiescence （17 months） five years before the Wen＇an earthquake. Simultaneously, the strain release curve showed a variation process of accelerating-flatting. ② A seismogenic gap in a three-dimensional space, located at the depth of 15km - 20km, with 70km long in latitude direction and 90km long in longitude orientation, was formed by M≥2.0 earthquakes four years prior to the Wen＇an earthquake. The initial rupture point of the Wen＇an earthquake is situated at the bottom of the gap. ③ The focal depths of earthquakes with ML ≥ 2. 0 in the middle part of the Hebei plain seismic belt gradually increased from 10km to 30kin during the period from April, 2003 to October, 2004. Meanwhile, the seismic activity obviously strengthened in the middle and lower crust （from 20km to 30km in depth）.
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment of China(Nos.2011ZX07303-001 and 2014ZX07303-003)the State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences(No.Y412201426)
文摘The migration of soil dissolved organic carbon(DOC) from terrestrial to aquatic environments has important impacts on the adjacent water quality and the transport of organic and inorganic contaminants.However,few studies have investigated the sources and properties of DOC in riparian zones.A total of 34 soil samples were collected across four riparian buffer zones(Zones A-D) on Chongming Island,China.The vertical distributions of soil organic carbon(SOC) and DOC,fluorescence excitation-emission matrix(EEM) spectra of DOC and the optical indices,including fluorescence index(FI),index of recent autochthonous contribution(BIX),and humification index(HIX),were measured across the riparian environment to investigate the sources and fluorescence properties of DOC.The results showed that SOC stored in the surface soil(0-30 cm) accounted for 40%of the total soil profile SOC.The DOC accumulated in Zones A-C,which accounted for 5%of the SOC.The fluorescence EEM spectra of DOC showed that DOC contained humic-like and protein-like substances,which were mainly derived from recent plant debris by microbes.A large amount of humic-like substances were sorbed to minerals in the surface soil(0-30 cm).In addition,the riparian topography and soil physico-chemical properties(pH,EC and moisture) dictated the transformation and transport of DOC.The results suggested that EEMs could reveal the source of DOC in riparian soil systems,and that optical indices were complementary tools that revealed the characteristics of soil DOC and provided supplemental evidence about DOC sources.
