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GIS-based Effect Assessment of Soil Erosion Before and After Gully Land Consolidation: A Case Study of Wangjiagou Project Region, Loess Plateau 被引量:32
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作者 LIU Yansui GUO Yanjun +1 位作者 LI Yurui LI Yuheng 《Chinese Geographical Science》 SCIE CSCD 2015年第2期137-146,共10页
The Loess Plateau is one typical area of serious soil erosion in the world. China has implemented ′Grain for Green′(GFG) project to restore the eco-environment of the Loess Plateau since 1999. With the GFG project s... The Loess Plateau is one typical area of serious soil erosion in the world. China has implemented ′Grain for Green′(GFG) project to restore the eco-environment of the Loess Plateau since 1999. With the GFG project subsidy approaching the end, it is concerned that farmers of fewer subsidies may reclaim land again. Thus, ′Gully Land Consolidation Project′(GLCP) was initiated in 2010. The core of the GLCP was to create more land suitable for farming in gullies so as to reduce land reclamation on the slopes which are ecological vulnerable areas. This paper aims to assess the effect of the GLCP on soil erosion problems by studying Wangjiagou project region located in the central part of Anzi valley in the middle of the Loess Plateau, mainly using the revised universal soil loss equation(RUSLE) based on GIS. The findings show that the GLCP can help to reduce soil shipment by 9.87% and it creates more terraces and river-nearby land suitable for farming which account for 27.41% of the whole study area. Thus, it is feasible to implement the GLCP in places below gradient 15°, though the GLCP also intensifies soil erosion in certain places such as field ridge, village land, floodplain, natural grassland, and shrub land. In short, the GLCP develops new generation dam land and balances the short-term and long-term interests to ease the conflicts between economic development and environmental protection. Furthermore, the GLCP and the GFG could also be combined preferably. On the one hand, the GFG improves the ecological environment, which could offer certain safety to the GLCP, on the other hand, the GLCP creates more farmland favorable for farming in gullies instead of land reclamation on the slopes, which could indirectly protect the GFG project. 展开更多
关键词 土地整理 黄土高原 土壤侵蚀 效果评估 GIS 项目区 通用土壤流失方程 生态脆弱地区
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Fuzzy Synthetic Evaluation of Wetland Soil Quality Degradation:A Case Study on the Sanjiang Plain,Northeast China 被引量:16
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作者 WANG Jian-Hua LU Xian-Guo +2 位作者 JIANG Ming LI Xiao-Yan TIAN Jing-Han 《Pedosphere》 SCIE CAS CSCD 2009年第6期756-764,共9页
Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursu... Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursuit evaluation (PPE) model based on real-coded accelerating genetic algorithm were introduced to evaluate quality variations in top layers of the main wetland soils on the Sanjiang Plain in 1999 and 2003, respectively. As soil quality degradation boundaries were vague, this study established two fuzzy synthetic evaluation (FSE) models based on the original data and criteria used in the RSQE and PPE models. The outputs of the two FSE models were obtained by choosing two fuzzy composite operators M(∧, ∨) and M(·, ⊕). Statistical analysis showed that the results of the FSE, RSQE, and PPE models were correlated. In particular, outputs of the FSE model using M(·, ⊕) were significantly correlated with those of the RSQE model with r = 0.989 at P < 0.01. Compared with RSQE and PPE models, the FSE model may be more objective in showing soil quality variations and was closer to the natural situation, showing the feasibility and applicability of the FSE model in evaluating soil quality degradation. However, the choice of composite operator was of critical importance. The study of wetland soil quality degradation on the Sanjiang Plain was of scientific and practical significance for protection and management of soils and for sustainable development of agriculture in this area in the future. 展开更多
关键词 土壤质量退化 模糊综合评价 三江平原 湿地 中国 东北
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Use of Intensity Analysis to Measure Land Use Changes from 1932 to 2005 in Zhenlai County, Northeast China 被引量:9
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作者 YANG Yuanyuan LIU Yansui +1 位作者 XU Di ZHANG Shuwen 《Chinese Geographical Science》 SCIE CSCD 2017年第3期441-455,共15页
Analyzing spatiotemporal dynamics of land use and land cover over time is widely recognized as important to better understand and provide solutions for social, economic, and environmental problems, especially in ecolo... Analyzing spatiotemporal dynamics of land use and land cover over time is widely recognized as important to better understand and provide solutions for social, economic, and environmental problems, especially in ecologically fragile region. In this paper, a case study was taken in Zhenlai County, which is a part of farming-pastoral ecotone of Northeast China. This study seeks to use multi-temporal satellite images and other data from various sources to analyze spatiotemporal changes from 1932 to 2005, and applied a quantitative methodology named intensity analysis in the time scale of decades at three levels: time interval, category, and transition. The findings of the case study are as follows: 1) the interval level of intensity analysis revealed that the annual rate of overall change was relatively fast in 1932–1954 and 1954–1976 time intervals. 2) The category level showed that arable land experienced less intensively gains and losses if the overall change was to have been distributed uniformly across the landscape while the gains and losses of forest land, grassland, water, settlement, wetland and other unused land were not consistent and stationary across the four time intervals. 3) The transition level illustrated that arable land expanded at the expense of grassland before 2000 while it gained intensively from wetland from 2000 to 2005. Settlement targets arable land and avoids grassland, water, wetland and other unused land. Besides, the loss of grassland was intensively targeted by arable land, forest land and wetland in the study period while the loss of wetland was targeted by water except for the time interval of 1976–2000. 4) During the early reclamation period, land use change of the study area was mainly affected by the policy, institutional and political factors, followed by the natural disasters. 展开更多
关键词 土地利用变化 东北农牧交错带 镇赉县 分析测量 使用强度 中国 生态脆弱地区 时间尺度
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Interactive effects of soil temperature and moisture on soil N mineralization in a Stipa krylovii grassland in Inner Mongolia, China 被引量:14
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作者 Yue LI YingHui LIU +3 位作者 YaLin WANG Lei NIU Xia XU YuQiang TIAN 《Journal of Arid Land》 SCIE CSCD 2014年第5期571-580,共10页
Determining soil N mineralization response to soil temperature and moisture changes is challenging in the field due to complicated effects from other factors. In the laboratory, N mineralization is highly dependent on... Determining soil N mineralization response to soil temperature and moisture changes is challenging in the field due to complicated effects from other factors. In the laboratory, N mineralization is highly dependent on temperature, moisture and sample size. In this study, a laboratory incubation experiment was carefully designed and conducted under controlled conditions to examine the effects of soil temperature and moisture on soil N mineralization using soil samples obtained from the Stipa krylovii grassland in Inner Mongolia, China. Five temperature(i.e. 9℃, 14℃, 22℃, 30℃ and 40℃) and five moisture levels(i.e. 20%, 40%, 60%, 80% and 100% WHC, where WHC is the soil water holding capacity) were included in a full-factorial design. During the 71-day incubation period, microbial biomass carbon(MBC), ammonium nitrogen(NH4 ^+-N) and nitrate nitrogen(NO3^--N) were measured approximately every 18 days; soil basal respiration for qCO2 index was measured once every 2 days(once a week near the end of the incubation period). The results showed that the mineral N production and net N mineralization rates were positively correlated with temperature; the strongest correlation was observed for temperatures between 30℃ and 40℃. The relationships between moisture levels and both the mineral N production and net N mineralization rates were quadratic. The interaction between soil temperature and moisture was significant on N mineralization, i.e. increasing temperatures(moisture) enhanced the sensitivity of N mineralization to moisture(temperature). Our results also showed a positive correlation between the net nitrification rate and temperature, while the correlation between the NH4 ^+-N content and temperature was insignificant. The net nitrification rate was negatively correlated with high NH4 ^+-N contents at 80%–100% WHC, suggesting an active denitrification in moist conditions. Moreover, qCO2 index was positively correlated with temperature, especially at 80% WHC. With a low net nitrification rate and high soil basal respiration rate, it was likely that the denitrification concealed the microbial gross mineralization activity; therefore, active soil N mineralization occurred in 60%–80% WHC conditions. 展开更多
关键词 soil N mineralization soil temperature soil moisture Stipa krylovii grassland
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Effects of vegetation types on soil water dynamics during vegetation restoration in the Mu Us Sandy Land, northwestern China 被引量:9
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作者 Yu Xiaona Huang Yongmei +2 位作者 Li Engui Li Xiaoyan Guo Weihua 《Journal of Arid Land》 SCIE CSCD 2017年第2期188-199,共12页
The arid and semi-arid northwestern China has been undergoing ecological degradation and the efforts to reverse the ecological degradation have been undertaken for many years. Some shifting dunes have been fixed and t... The arid and semi-arid northwestern China has been undergoing ecological degradation and the efforts to reverse the ecological degradation have been undertaken for many years. Some shifting dunes have been fixed and the vegetation has been partially recovered in certain areas and the Mu Us Sandy Land in the Ordos Plateau is an example of the success. The present study attempts to reveal the relationships between the vegetation restoration and ecohydrology in the Mu Us Sandy Land. We continuously measured soil water content at 10-min intervals under three vegetation types (i.e., shifting dune, shrub-dominated community, and herb-dominated community) in the Mu Us Sandy Land from April 2012 to October 2013. The results show the infiltration coefficient increased with increased rainfall amount and eventually reached a stable value. Infiltration coefficients were 0.91, 0.64, and 0.74 in the shifting dune, in the shrub-dominated community, and in the herb-dominated community, respectively. Cumulative infiltration and soil texture are two vital factors affecting the depths of rainfall penetration. Only rainfall events larger than 35.0 mm could recharge soil water at the 60-80 cm layer in the herb-dominated community. Our results imply that the expected forward succession of restored vegetation may be destined to deterioration after reaching the climax simply because of following two facts: (1) soil water is mainly retained at shallower layer and (2) plant fine roots mainly distribute in deeper layer in the herb-dominated community. 展开更多
关键词 ECOHYDROLOGY soil water content vegetation restoration Artemisia ordosica community
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Diagenesis and reservoir quality of the fourth member sandstones of Shahejie formation in Huimin depression,eastern China 被引量:4
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作者 张金亮 李德勇 江志强 《Journal of Central South University》 SCIE EI CAS 2010年第1期169-179,共11页
Petrographic analysis combined with various techniques, such as scanning electron microscopy and X-ray diffraction, was used to assess the timing of growth and original mineral cements, the controls on reservoir and r... Petrographic analysis combined with various techniques, such as scanning electron microscopy and X-ray diffraction, was used to assess the timing of growth and original mineral cements, the controls on reservoir and reservoir quality of the fourth member sandstones of Shahejie formation (Es4). The Es4 sandstones are mostly arkose and lithic arkose, rarely feldspathic litharenite, with an average mass fraction of quartz 51.6%, feldspar 33.8% and rock fragments 14.6% (Q51.6F33.8R14.6). They have an average framework composition (mass fraction) of quartz 57.10%, K-feldspar 5.76%, sodium-calcium feldspar 13.00%, calcite 5.77%, dolomite 5.63%, siderite 0.95%, pyrite 0.30%, anhydrite 0.04%, and clay mineral 11.46%. The diagenentic minerals typically include kaolinite, illite-smectite (I/S), illite, chlorite, authigenetic quartz and feldspar, and carbonate and pyrite. Es4 sandstone has undergone stages A and B of eodiagenesis, and now, it is experiencing stage A of mesodiagenesis. Reservoir quality is predominantly controlled by the mechanical compaction, for example, 45.65% of the original porosity loss is related to compaction. The original porosity loss related with cementation is only 26.00%. The reservoir quality is improved as a result of dissolution of feldspar, rock fragment and so forth. The porosity evolved from dissolution varies from 3% to 4%. 展开更多
关键词 长石砂岩 质量分数 沙河街组 惠民凹陷 成岩作用 中国东部 扫描电子显微镜 压实控制
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The influence of different underlying surface on sand-duststorm in northern China 被引量:4
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作者 SONG Yang QUAN Zhanjun LIU Lianyou YAN Ping CAO Tong 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期431-438,共8页
In this paper, a quantitative research on the relationship between different underlying surface and sand-dust storm has been made by using 40 years meteorological data of five different types of underlying surface in ... In this paper, a quantitative research on the relationship between different underlying surface and sand-dust storm has been made by using 40 years meteorological data of five different types of underlying surface in northern China, which include farmland, grassland, sandland, gobi and salt crust. These metrological data comprise sand-dust storm days and strong wind days. By analyzing, we can find that there are certain correlations between the days of sand-dust storm and strong wind for different underlying surface, which has great influence on sand-dust storm. But there are pronounced differences in different types of underlying surface. The sand-dust storm days of grassland, gobi and salt crust, with smaller interannual variation are obviously less than strong wind days. On the other hand, the sand-dust storm days of farmland and sandland increase evidently, even in many years, are much more than strong wind days. The differences are mainly induced by the influencing mechanism of different underlying surface on sand-dust storm. Grassland, gobi and salt crust with stable underlying surface are not prone to sand-dust storm under strong wind condition. Whereas, the underlying surface of farmland and sandland is unstable, that is easy to induce sand-dust storm under strong wind condition. 展开更多
关键词 sand-dust storm underlying surface strong wind northern China
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Landscape pattern change and driving force of blowout distribution in the Hulun Buir Sandy Grassland 被引量:6
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作者 Eerdun Hasi 《Research in Cold and Arid Regions》 2012年第5期431-438,共8页
The land coverage pattern changes for the past 50 years in a typical region of the Hulun Buir Sandy Grassland were interpreted and analyzed based on a series of remote sensing images in 1959, 2002, 2004 and 2009. The ... The land coverage pattern changes for the past 50 years in a typical region of the Hulun Buir Sandy Grassland were interpreted and analyzed based on a series of remote sensing images in 1959, 2002, 2004 and 2009. The temporal and spatial changes of landscape patterns were revealed and the driving forces were analyzed. The results show that all land coverage types had large variable amplitudes. The grassland area decreased, whereas other areas incleased. Owing to implementation of artificial sand fixation from 2004 to 2009, the areas of flowing blowouts and depositional area decreased by 71,369 and 128,835 m2, respectively. The average patch area reduced, but the number of blowouts increased, fractal dimension increased, and blowout structure became complex. The fragmentation index increased, whereas contagion index decreased. Driving force analysis shows that human factors such as overglazing are slightly larger than natural factors of increased temperature and decreased precipitation 展开更多
关键词 BLOWOUT landscape pattems Hukm Buir driving force
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A review of the research on complex erosion by wind and water 被引量:3
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作者 SONG Yang YAN Ping LIU Lianyou 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期231-241,共11页
Complex erosion by wind and water, which is also called aeolian-fluvial interactions, is an important erosion process and landscape in arid and semiarid regions. The effectiveness of links between wind and water proce... Complex erosion by wind and water, which is also called aeolian-fluvial interactions, is an important erosion process and landscape in arid and semiarid regions. The effectiveness of links between wind and water process, spatial environmental transitions and temporal environmental change are the three main driving forces determining the geomorphologic significance of aeolian-fluvial interactions. As a complex interrelating and intercoupling system, complex erosion by wind and water has spatial- temporal variation features. The process of complex erosion by wind and water can be divided into palaeoenvironmental process and contemporary process. Early work in drylands has often been attributed to one of two schools advocating either an 'aeolianist' or a 'fluvialist' perspective, so it was not until the 1930s that the research on complex erosion by wind and water had been conducted. There are two obstacles restricting the research of complex erosion by wind and water. Firstly, how to transform in different temporal and spatial scales is still unsettled; and secondly, the research methodology is still immature. In the future, the mechanism and control of erosion, the complex soil erodibility in wind and water erosion will be the focus of research on complex erosion by wind and water. 展开更多
关键词 complex erosion by wind and water aeolian-fluvial interactions semiarid regions sediment contemporary process
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Evaporative enrichment of stable isotopes(δ^(18)O and δD) in lake water and the relation to lake-level change of Lake Qinghai, Northeast Tibetan Plateau of China 被引量:4
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作者 WU Huawu LI Xiaoyan +3 位作者 LI Jing JIANG Zhiyun LI Guangyong LIU Lei 《Journal of Arid Land》 SCIE CSCD 2015年第5期623-635,共13页
Stable isotopic compositions (δ18O and 6D) have been utilized as a useful indicator for evaluating the current and historical climatic and environmental changes. Therefore, it is vital to understand the relationshi... Stable isotopic compositions (δ18O and 6D) have been utilized as a useful indicator for evaluating the current and historical climatic and environmental changes. Therefore, it is vital to understand the relationship be- tween the stable isotopic contents in lake water and the variations of lake level, particularly in Lake Qinghai, China. In this study, we analyzed the variations of isotope compositions (δ18O, 6D and d-excess) in lake water and pre- cipitation by using the samples that were collected from Lake Qinghai region during the period from 2009 to 2012. The results showed that the average isotopic contents of δ18O and 6D in lake water were higher than those in pre- cipitation, which were contrary to the variations of d-excess. The linear regression correlations between δ18O and 6D in lake water and precipitation showed that the local evaporative line (LEL) in lake water (δD=5.88δ18O-2.41) deviated significantly from the local meteoric water line (LMWL)in precipitation (δD=8.26δ18O+16.91), indicating that evaporative enrichment had a significant impact on isotopic contents in lake water. Moreover, we also quanti- fied the Eli ratio (evaporation-to-input ratio) in Lake Qinghai based on the lake water isotopic enrichment model derived from the Rayleigh equation. The changes of E/I ratios (ranging from 0.29 to 0.36 between 2009 and 2012) clearly revealed the shifts of lake levels in Lake Qinghai in recent years. The average E/I ratio of 0.40 reflected that water budget in Lake Qinghai was positive, and consistent with the rising lake levels and the increasing lake areas in many lakes of the Tibetan Plateau. These findings provide some evidences for studying the hydrological balance or water budget by using δ18O values of lake sedimentary materials and contribute to the reconstruction of paleo- lake water level and paleoclimate from an isotopic enrichment model in Lake Qinghai. 展开更多
关键词 stable isotopes d-excess lake level E/I ratio isotopic enrichment model PALEOCLIMATE
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Water and Energy Conservation of Rainwater Harvesting System in the Loess Plateau of China 被引量:3
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作者 JIANG Zhi-yun LI Xiao-yan MAYu-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1389-1395,共7页
Water is the source of all the creatures on the earth and energy is the main factor driving the world. With the increasing population and global change, water and energy conservation have become worldwide focal issues... Water is the source of all the creatures on the earth and energy is the main factor driving the world. With the increasing population and global change, water and energy conservation have become worldwide focal issues, particularly in the water-stressed and energy-limited regions. Rainwater harvesting, based on the collection and storage of rainfall runoff, has been widely used for domestic use and agricultural production in arid and semiarid regions. It has advantages of simple operation, high adaption, low cost and less energy consumption. This study reviewed rainwater harvesting systems adopted in the Loess Plateau of China and analyzed water use efficiency (WUE) for various rainwater harvesting techniques. Supplemental irrigation using harvested rainwater could increase crop yield by more than 30%, and WUE ranged from 0.7 to 5.7 kg m4 for spring wheat, corn and flax, and 30-40 kg m-3 for vegetables. Moreover, energy consumption for rainwater harvesting based on single family was compared with traditional water supply in the city of the Loess Plateau using the life cycle assessment (LCA) method. Results showed that energy consumption yielded per unit harvested rainwater was 25.96 MJ m-3 yr which was much less than 62.25 MJ m3 yr^-1 for main water supply in Baoji City, Shanxi Province, meaning that rainwater harvesting saved energy by 139.8% as compared to the main water supply system. This study highlights the importance and potential of rainwater harvesting for water and energy conservation in the near future. 展开更多
关键词 rainwater harvesting water saving energy conservation life cycle assessment (LCA)
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Diurnal and seasonal variation of the elevation gradient of air temperature in the northern flank of the western Qinling Mountain range,China 被引量:3
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作者 WANG Guo-yi ZHAO Ming-fei +4 位作者 KANG Mu-yi XING Kai-xiong WANG Yu-hang XUE Feng CHEN Chen 《Journal of Mountain Science》 SCIE CSCD 2017年第1期94-105,共12页
The typically sparse or lacking distribution of meteorological stations in mountainous areas inadequately resolves temperature elevation variability. This study presented the diurnal and seasonal variations of the ele... The typically sparse or lacking distribution of meteorological stations in mountainous areas inadequately resolves temperature elevation variability. This study presented the diurnal and seasonal variations of the elevation gradient of air temperature in the northern flank of the western Qinling Mountain range,which has not been thoroughly evaluated. The measurements were conducted at 9 different elevations between 1710 and 2500 m from August 2014 to August 2015 with HOBO Data loggers. The results showed that the annual temperature lapse rates(TLRs) for Tmean,Tmin and Tmax were 0.45?C/100 m,0.44?C/100 m and 0.40?C/100 m,respectively,which are substantially smaller than the often used value of 0.60°C/100 m to 0.65°C/100 m. The TLRs showed no obvious seasonal variations,except for the maximum temperature lapse rate,which was steeper in winter and shallower in spring. Additionally,the TLRs showed significant diurnal variations,with the steepest TLR in forenoon and the shallowest in early morning or late-afternoon,and the TLRs changed more severely during the daytime than night time. The accumulated temperature above 0°C,5°C and 10°C(AT0,AT5 and AT10) decreased at a lapse rate of 112.8?C days/100 m,104.5?C days/100 m and 137.0?C days/100 m,respectively. The monthly and annual mean diurnal range of temperatures(MDRT and ADRT) demonstrated unimodal curves along the elevation gradients,while the annual range of temperature(ART) showed no significant elevation differences. Our results strongly suggest that the extrapolated regional TLR may not be a good representative for an individual mountainside,in particular,where there are only sparse meteorological stations at high elevations. 展开更多
关键词 温度日变化 季节变化 海拔梯度 西秦岭 北缘 Toll样受体 空气 中国
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Relationships between tree-ring cell features of Pinus koraiensis and climate factors in the Changbai Mountains,Northeastern China 被引量:4
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作者 Hui Wang Xuemei Shao +3 位作者 Xiuqi Fang Yuan Jiang Chunlan Liu Qing Qiao 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第1期105-114,共10页
Anatomical characteristics have been proven useful for extracting climatic signals. To examine the climatic signals recorded by tree-ring cell features in the Changbai Mountains, we measured cell number and cell lumen... Anatomical characteristics have been proven useful for extracting climatic signals. To examine the climatic signals recorded by tree-ring cell features in the Changbai Mountains, we measured cell number and cell lumen diameter, in addition to ring widths, of Korean pine (Pinus koraiensis) tree rings at sites of varied elevation, and we developed chronologies of cell number (CN), mean lumen diameter (MLD), maximum lumen diameter (MAXLD) and tree-ring width (TRW). The chronologies were correlated with climatic factors monthly mean tem- perature and the sum of precipitation. As shown by our analysis, the cell parameter chronologies were suitable for dendroclimatology studies. CN and TRW shared relatively similar climatic signals which differed from MLD and MAXLD, and growth-climate relationships were elevation- dependent, as shown by the following findings: (1) at each elevation, MLD and MAXLD recorded different monthly climatic signals from those recorded by TRW for the same climatic factors; and (2) MLD and MAXLD recorded cli- matic factors that were absent middle elevations. Cell lumen effective archive for improving for this study area. from TRW at lower and diameter proved to be an the climate reconstruction 展开更多
关键词 Climate variability Cell features Pinuskoraiensis DENDROCLIMATOLOGY Growth-climaterelationships
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Effects of converting natural grasslands into planted grasslands on ecosystem respiration: a case study in Inner Mongolia, China 被引量:2
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作者 ZHANG Meng LI Xiaobing +3 位作者 WANG Hong DENG Fei LI Xu MI Xue 《Journal of Arid Land》 SCIE CSCD 2017年第1期38-50,共13页
With increasingly intensifying degradation of natural grasslands and rapidly increasing demand of high quality forages, natural grasslands in China have been converted into planted grasslands at an unprecedented rate ... With increasingly intensifying degradation of natural grasslands and rapidly increasing demand of high quality forages, natural grasslands in China have been converted into planted grasslands at an unprecedented rate and the magnitude of the conversion in Inner Mongolia is among the national highest where the areal extent of planted grasslands ranks the second in China. Such land-use changes(i.e., converting natural grasslands into planted grasslands) can significantly affect carbon stocks and carbon emissions in grassland ecosystems. In this study, we analyzed the effects of converting natural grasslands into planted grasslands(including Medicago sativa, Elymus cylindricus, and M. sativa+E. cylindricus) on ecosystem respiration(F(eco)) in Inner Mongolia of China. Diurnal F(eco) and its components(i.e., total soil respiration(F(ts)), soil heterotrophic respiration(F(sh)) and vegetation autotrophic respiration(F(va))) were measured in 2012(27 July to 5 August) and 2013(18 July to 25 July) in the natural and planted grasslands. Meteorological data, aboveground vegetation data and soil data were simultaneously collected to analyze the relationships between respiration fluxes and environmental factors in those grasslands. In 2012, the daily mean F(eco) in the M. sativa grassland was higher than that in the natural grassland, and the daily mean F(va) was higher in all planted grasslands(i.e., M. sativa, E. cylindricus, and M. sativa+E. cylindricus) than in the natural grassland. In contrast, the daily mean F(ts) and F(sh) were lower in all planted grasslands than in the natural grassland. In 2013, the daily mean F(eco), F(ts) and F(va) in all planted grasslands were higher than those in the natural grassland, and the daily mean F(sh) in the M. sativa+E. cylindricus grassland was higher than that in the natural grassland. The two-year experimental results suggested that the conversion of natural grasslands into planted grasslands can generally increase the F(eco) and the increase in F(eco) is more pronounced when the plantation becomes more mature. The results also indicated that F(sh) contributed more to F(eco) in the natural grassland whereas F(va) contributed more to F(eco) in the planted grasslands. The regression analyses show that climate factors(air temperature and relative humidity) and soil properties(soil organic matter, soil temperature, and soil moisture) strongly affected respiration fluxes in all grasslands. However, our observation period was admittedly too short. To fully understand the effects of such land-use changes(i.e., converting natural grasslands into planted grasslands) on respiration fluxes, longer-term observations are badly needed. 展开更多
关键词 natural grasslands planted grasslands ecosystem respiration soil respiration vegetation autotrophicrespiration Inner Mongoia
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Changes and spatial patterns of eco-environment in the farming-pastoral region of northern China 被引量:2
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作者 JIANG Weiguo LI Jing +2 位作者 LI Jiahong CHEN Yunhao WU Yongfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第3期329-336,共8页
This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then di... This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then discusses in detail the methods about evaluating eco-environment background condition and analyzing eco-environment change. The eco-environment background conditions of 1989 and 1999 are synthetically appraised. Finally, the paper analyzes the spatial distribution, quantitative change, the trend of change, the areas of change and the dynamic spatial pattern of eco-environment. The results are as follows: (1) The eco-environment background condition becomes worse from southeast to northwest in the fanning-pastoral region of northern China. (2) The eco-environment background condition deteriorates from 1989 to 1999. (3) In the adjacent areas of Shanxi-Shaanxi-Inner Mongolia-Gansu-Ningxia, Horqin Sandy Land and its peripheries, and eastern Qinghai orovince, eco-environmental deterioration is very serious. 展开更多
关键词 fanning-pastoral region ECO-ENVIRONMENT spatial pattern northern China
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Effects of grassland management on the community structure, aboveground biomass and stability of a temperate steppe in Inner Mongolia, China 被引量:6
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作者 ZHANG Jinghui HUANG Yongmei +4 位作者 CHEN Huiying GONG Jirui QI Yu YANG Fei LI Engui 《Journal of Arid Land》 SCIE CSCD 2016年第3期422-433,共12页
Plant community structure responds strongly to anthropogenic disturbances, which greatly influence community stability. The changes in community structure, aboveground biomass(AGB), biodiversity and community stabil... Plant community structure responds strongly to anthropogenic disturbances, which greatly influence community stability. The changes in community structure, aboveground biomass(AGB), biodiversity and community stability associated with different management practices were studied with a three-year field investigation in a temperate steppe of Inner Mongolia, China. The species richness, Shannon-Wiener index, evenness, plant functional type abundance, AGB, temporal community stability, summed covariance, scaling coefficient and dominant species stability were compared among areas subjected to long-term reservation(R), long-term grazing(G), mowing since enclosure in 2008(M) and grazing enclosure since 2008(E). Site R had higher perennial grass abundance and lower species richness than sites G, M and E, although the AGB was not significantly different among the four sites. The species structure varied from a single dominant species at site R to multiple dominant species at sites G, M and E. The long-term reservation grassland had lower biodiversity but higher stability, whereas the enclosed grassland with/without mowing had higher biodiversity but lower stability. Different stability mechanisms, such as the compensatory dynamics, mean-variance scaling and dominant species stability were examined. Results showed that community stability was most closely related to the relative stability of the dominant species, which supports the biomass ratio hypothesis proposed by Grime. 展开更多
关键词 dominant species biodiversity indices mass ratio hypothesis variance-mean scaling compensatory dynamics
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Grazing every month minimizes size but boosts photosynthesis in Stipa grandis in the steppe of Inner Mongolia, China 被引量:1
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作者 LI Xiaobing HUANG Qi +3 位作者 MI Xue BAI Yunxiao ZHANG Meng LI Xu 《Journal of Arid Land》 SCIE CSCD 2018年第4期601-611,共11页
In order to explore the effects of grazing frequency on functional traits and to test whether Slipa gandis has compensatory photosynthesis during the frequent grazing period, we investigated morphological traits, biom... In order to explore the effects of grazing frequency on functional traits and to test whether Slipa gandis has compensatory photosynthesis during the frequent grazing period, we investigated morphological traits, biomass allocation, photosynthetic traits, and chlorophyll fluorescence parameters of the species in Inner Mongolia, China. The grazing frequency treatments included fencing (To), grazing in May and July (T1, i.e., two months per year) and grazing from May to September (T2, i.e., continuous five months per year). Results indicate that T1 and T2 treatments did not affect individual biomass, but T2 treatment negatively affected individual size, i.e., plant height, stem length, and leaf length. Physiological traits of S. grandis were significantly affected by grazing, year, and their interaction. In July 2014 (i.e., dry environment and low relative humidity), the photosynthetic rate, transpiration rate and water use efficiency were highest under T2 treatment, which was caused by the increase in stomatal conductance. However, in July 2015 (i.e., 展开更多
关键词 grazing frequency morphological traits gas exchange photochemical efficiency water use efficiency
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On Urban Heat Island of Beijng Based on Landsat TM Data 被引量:1
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作者 JIANG Zhangyan CHEN Yunhao LI Jing 《Geo-Spatial Information Science》 2006年第4期293-297,共5页
Land surface temperature (LST) of Beijing area was retrieved from Landsat TM thermal band data utilizing a radiative transfer equation and the urban heat island (HUI) effects of Beijing and its relationship with land ... Land surface temperature (LST) of Beijing area was retrieved from Landsat TM thermal band data utilizing a radiative transfer equation and the urban heat island (HUI) effects of Beijing and its relationship with land cover and normalized difference vegetation index (NDVI) were discussed. The result of LST showed that the urban LST was evidently higher than the suburban one. The average urban LST was found to 4.5 ℃ and 9 ℃ higher than the suburban and outer suburban temperature, respectively, which demonstrated the prominent UHI effects in Beijing. Prominent negative correlation between LST and NDVI was found in the urban area, which suggested the low percent vegetation cover in the urban area was the main cause of the urban heat island. 展开更多
关键词 土壤表面温度 城市热岛效应 陆地卫星 温度变化
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Application of Refactoring and Design Pattern in Land Information System Development 被引量:1
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作者 CHEN Luyao YUE Jianwei +2 位作者 JIANG Weiguo LI Jing CHEN Yunhao 《Geo-Spatial Information Science》 2007年第4期299-302,共4页
土地信息系统的不停的变化问题能通过重新分解和设计模式被解决。为了在开发再使用软件的土地信息系统支持设计模式和重新分解的方法的实现,设计,适用重新分解在土地信息系统开发的模式被讨论的到抽象工厂和装饰者设计的方法。
关键词 土地信息系统 系统开发 重构 设计模式 GIS
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Physical principle of wind erosion on sandy land surface in southern Beijing 被引量:1
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作者 YUE Depeng LIU Yongbing +2 位作者 WANG diping LI Hailong CUI Weijia 《Journal of Geographical Sciences》 SCIE CSCD 2006年第4期487-494,共8页
The endangerment of aeolian sand is one of the most serious eco-environmental problems facing the southern suburb of Beijing. To control wind erosion is thus a matter of great urgency. This paper chooses typical land-... The endangerment of aeolian sand is one of the most serious eco-environmental problems facing the southern suburb of Beijing. To control wind erosion is thus a matter of great urgency. This paper chooses typical land-use types, i.e., cultivated land, wild grassland, drifting sandy land, etc. based on the fixed experimental observation and quantitative analysis, to conduct studies on the principles and characteristics of aeolian activities and measures controlling wind erosion in Daxing District of Beijing, The results show that: the near ground wind velocity yielded the logarithmic distribution with height; there are significant differences among different ground cover roughness; there are significant differences in the corresponding friction velocities caused by different properties of the underlying surface; there are differences in the threshold wind velocities speed in different land .use types; and there are minus exponential relations between the sediment discharge percentage and the height at a range of 0-20 cm air flow layer, Different land use types result in various degrees of coarse component. There is a significant exponential relation between sediment transport concentration and wind velocity. 展开更多
关键词 BEIJING wind erosion physical principle comprehensive tackle of Sandy land
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