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云南金沙江干热河谷地区麻疯树生物量的变化
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作者 陈喜英 谷勇 +2 位作者 殷瑶 吴昊 齐泮仑 《贵州农业科学》 CAS 北大核心 2011年第4期174-176,共3页
为实现麻疯树资源的可持续利用和科学管理,并为估算麻疯树生态系统的碳汇提供依据,于2009年7月对云南省金沙江干热河谷地区的元谋、永胜、华坪3县半野生的麻疯树进行了生物量调查。结果表明:6~15年生麻疯树生理活动达到高峰期,生物量... 为实现麻疯树资源的可持续利用和科学管理,并为估算麻疯树生态系统的碳汇提供依据,于2009年7月对云南省金沙江干热河谷地区的元谋、永胜、华坪3县半野生的麻疯树进行了生物量调查。结果表明:6~15年生麻疯树生理活动达到高峰期,生物量迅速增加;地上部分生物量与主干、叶、枝条的生物量符合线性模型,各构件生物量与树龄的关系符合生长曲线模型,其中地上部分生物量与树龄的关系符合3次曲线方程,地下部分生物量与树龄的关系符合逻辑曲线方程;地上部分各构件生物量比率随树龄的变化呈不同的变化规律;根系中主根生物量最大,占全根系的58.7%~82.6%,须根最小,仅占0.7%~6.2%。 展开更多
关键词 麻疯树 生物量 金沙江 云南 干热谷地区
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遥感与DEM辅助下的元谋干热环境识别与分析 被引量:1
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作者 赵红梅 陈晓玲 +1 位作者 熊明 王素芳 《遥感学报》 EI CSCD 北大核心 2008年第1期135-142,共8页
在干热谷地区的研究中,大都根据海拔高度划定干热谷气候区的范围。而实际上,干热谷景观同时受地形特征(包括高程、坡度和坡向)和人类活动的多重影响。单纯利用高程信息划分干热谷景观区,而没有考虑以上多种因素的影响,显然难以正确地识... 在干热谷地区的研究中,大都根据海拔高度划定干热谷气候区的范围。而实际上,干热谷景观同时受地形特征(包括高程、坡度和坡向)和人类活动的多重影响。单纯利用高程信息划分干热谷景观区,而没有考虑以上多种因素的影响,显然难以正确地识别不同的自然景观。本文以最为典型的元谋干热谷为例,首先利用多波段混合运算方法提取山体阴影区,从而剔除坡向的影响;然后,以DEM数据为基础,针对陆地卫星影像,分别采用土地利用绘图法、陆面温度阈值法和干热指数法(RTVI,Ratio of Temperature and NDVI)三种方法对干热谷景观进行识别;最后,利用景观生态学方法对以上识别结果进行对比分析。结果发现,干热指数用于识别干热谷景观区域是最为简单可行的方法;从研究区域的典型干热谷景观分布特征来看,该景观虽然已远远超出传统高程划分的1350m上限,但是,超出这一上限的干热谷景观斑块相对破碎,水体及植被斑块与干热谷景观斑块交错连接,说明这一区域生态恢复的能力较强。 展开更多
关键词 元谋 干热谷 多波段混合运算 指数(RTVI) 红外
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Influence of Vegetation Coverage on Surface Runoff and Soil Moisture in Rainy Season in Dry-hot Valley 被引量:7
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作者 郭芬芬 南岭 +1 位作者 陈安强 刘刚才 《Agricultural Science & Technology》 CAS 2010年第4期138-143,共6页
[Objective]The research aimed to study the effects of vegetation coverage on the changes of soil moisture in rainy season in dry-hot valley.[Method]The surface runoff and soil moisture of slope with vegetation coverag... [Objective]The research aimed to study the effects of vegetation coverage on the changes of soil moisture in rainy season in dry-hot valley.[Method]The surface runoff and soil moisture of slope with vegetation coverage and bare land in rainy reason in Jinsha River at Yuanmou County of Yunnan Province were observed continuously.Moreover,the statistical analysis was made based on the observation data.[Result]The vegetation coverage could decrease surface runoff and the surface runoff on bare land(CK) was 22 times as the plot with vegetation coverage.The soil water content in 0-180 cm layer with vegetation coverage increased by 37.8% than bare land.The stability of soil moisture content in deep layer was enhanced and the physical properties stability of soil was maintained.The soil moisture content in different depth of soil had significant difference and the changes of soil moisture content were obviously different.[Conclusion]The vegetation coverage of slope could change the soil hydrology obviously and keep soil moisture at the higher level,especially at soil layer below 20 cm. 展开更多
关键词 Vegetation coverage Surface runoff Soil moisture Dry-hot valley
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Effect of Typical Vegetation Restoration Pattern on Soil and Water Conservation in Yuanmou Dry-hot Valley of Yunnan Province 被引量:1
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作者 南岭 郭芬芬 +1 位作者 王小丹 刘刚才 《Agricultural Science & Technology》 CAS 2010年第11期167-171,201,共6页
In Yuanmou dry-hot valley of Yunnan Province,three typical vegetation restoration patterns including production forest transformed from sloping fields to terracing,ecological afforestation within the gully and ecologi... In Yuanmou dry-hot valley of Yunnan Province,three typical vegetation restoration patterns including production forest transformed from sloping fields to terracing,ecological afforestation within the gully and ecological aforestation in gully head and slope were selected to compare their effects on soil and water conservation.Soil and water loss,soil infiltration rate and the soil moisture dynamics of soil profile with the depth of 0-100 cm of these three patterns and their controls were observed by established standard observation plots in rainy season.The results showed that the soil and water loss of ecological afforestation and production forest terrace reduced by over 30% and 60% compared with their controls(without growth of any vegetation)respectively,showing significant control effect on the soil and water loss.Vegetation restoration also apparently increased the infiltration rate of soil(increased by 100%-200%).In rainy season,the soil moisture content of ecological afforestation and production forest terrace increased by over 30% and 100% compared with their controls.This indicated that vegetation restoration will not lead to soil aridity during the rainy season;vegetation restoration not only reduced the loss of surface water and soil fine particles,but also enhanced the infiltration of precipitation.These two effects made the soil moisture content increase throughout the profile. 展开更多
关键词 Dry-hot valley Soil and water loss Vegetation restoration Soil moisture
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The dry-hot valleys and forestation in southwest china 被引量:6
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作者 马焕成 Jack A.McConchie 《Journal of Forestry Research》 CAS CSCD 2001年第1期35-39,共7页
The dry-hot valleys (DHV) are located mainly in the deeply incised v alleys along the upper streams of several international and domestically rivers, like Yangtz, Zhu, Lanchang, Hong, and Nu rivers. This paper briefl... The dry-hot valleys (DHV) are located mainly in the deeply incised v alleys along the upper streams of several international and domestically rivers, like Yangtz, Zhu, Lanchang, Hong, and Nu rivers. This paper briefly described t he reasons of formation of DHV from view of climate and geographical conditions, and by referring to great deal of documents, analyzed the historical case and p resent status of the vegetations in DHV. The environment in DHV is facing the se rious vulnerable period in the history due to its nature situation of half-year dry period, fragile geological structure and shallow soil, and its social situat ion of over dense population and over farming. The primary vegetation is broad l eaf forest and it was denuded in the history. The current local vegetation is th e degraded secondary vegetation: savanna and succulent thorny shrub. Since the e nvironmental situation in valley influenced directly the water body of river, th e soil erosion control and re-vegetation in DHV is the most urgent task in the p rocess of environmental harness along the rivers. Quite a few pilot research pro jects have been carried out.on demonstrating new silviculture techniques for re- vegetation in DHV, but there still exist great difficulties in carrying out larg e-scale afforestation engineering. 展开更多
关键词 Dry-hot valley Forestation Environmental harness
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Livelihood Strategy and Farmland Use in Xinping County of Yuanjiang Dry-hot Valley 被引量:1
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作者 赵文娟 杨世龙 王潇 《Agricultural Science & Technology》 CAS 2016年第4期977-982,共6页
Methods of participatory rural appraisal and mathematical statistics were adopted to study livelihood diversification, livelihood strategy and farmland use of the four types of farmers in Xinping County of Yuanjiang d... Methods of participatory rural appraisal and mathematical statistics were adopted to study livelihood diversification, livelihood strategy and farmland use of the four types of farmers in Xinping County of Yuanjiang dry-hot valley with field survey data. The results showed as follows: firstly, as farmers are transforming from pure agriculture to non-agriculture, their agricultural livelihood diversification index will decrease, while non-agricultural livelihood diversification index will increase. In term of livelihood activities, pure agricultural farmers are exclusively engaged in agricultural activities, agricultural-dominant and non-agricultural-dominant farmers are engaged in both agricultural and non-agricultural ones, while non-agricultural farmers are basically engaged in off-farm activities. Secondly, as for crops planted, pure agricultural and agricultural-dominant farmers tend to choose those crops with more investment,shorter growth period and higher value, meanwhile non-agricultural-dominant farmers tend to choose crops with less investment, simpler management and longer growth period. Thirdly, to cope with current problems in farming, pure agricultural farmers will adopt measures such as changing planting structure, maintaining or expanding planting scale, increasing planting investment and renting in more land to promote the development of farming; agriculture-dominant farmers will adopt measures such as changing planting structure, reducing planting scale, maintaining planting investment, renting in and taking back the leased land as well as engaging in non-agricultural activities to overcome the difficulties faced; while non-agricultural-dominant farmers will adopt measures such as reducing both planting scale and investment,changing planting structure and engaging in farmland transfer as well as various offfarm activities to avoid livelihood risks. 展开更多
关键词 Xinping County of Yuanjiang dry-hot valley Farmers' livelihood activities Farmland use
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Preliminary Study on Biological Characteristics of Degraded Soil Ecosystems in Dry Hot Valley of the Jinsha River 被引量:21
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作者 HEYURONG YANGWANQIN +1 位作者 WANGKAIYUN SONGGUANGYU 《Pedosphere》 SCIE CAS CSCD 2002年第4期365-372,共8页
Distribution characteristics of soil animals, microorganisms and enzymatic activity were studied in the dry red soil and Vertisol ecosystems with different degradation degrees in the Yuanmou dry hot valley of the Jins... Distribution characteristics of soil animals, microorganisms and enzymatic activity were studied in the dry red soil and Vertisol ecosystems with different degradation degrees in the Yuanmou dry hot valley of the Jinsha River, China. Results showed that Hymenoptera, Araneae and Collembola were the dominant groups of soil animals in the plots studied. The numbers of groups and individuals and density of soil animals in the dry red soil series were higher than those in the Vertisol series, and the numbers of individuals and density of soil animals decreased with the degree of soil degradation. Bacteria dominated microbiocoenosis not only in the dry red soils but also in the Vertisols. Microbial numbers of the dry red soil series were higher than those of Vertisol series, and decreased with the degree of soil degradation. The activities of catalase, invertase, urease and alkaline phosphatase declined with the degradation degree and showed a significant decline with depth in the profiles of both the dry red soils and the Vertisols, but activities of polyphenol oxidase and acid and neutral phosphatase showed the same tendencies only in the Vertisols. It was concluded that the characteristics of soil animals, microorganisms and enzymatic activity could be used as the bio-indicators to show the degradation degree of the dry red soils and Vertisols. Correlation among these soil bio-indicators was highly significant. 展开更多
关键词 degraded soil ecosystem soil enzyme soil fauna soil microbes
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SLOPE LITHOLOGIC PROPERTY, SOIL MOISTURE CONDITION AND REVEGETATION IN DRY-HOT VALLEY OF JINSHA RIVER 被引量:5
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作者 XIONGDong-hong ZHOUHong-yi +1 位作者 YANGZhong ZHANGXin-bao 《Chinese Geographical Science》 SCIE CSCD 2005年第2期186-192,共7页
The dry-hot valley of the Jinsha River is one of the typical eco-fragile areas in Southwest China, as well as a focus of revegetation study in the upper and middle reaches of the Changjiang River. Due to its extremely... The dry-hot valley of the Jinsha River is one of the typical eco-fragile areas in Southwest China, as well as a focus of revegetation study in the upper and middle reaches of the Changjiang River. Due to its extremely dry and hot climate, severely degraded vegetation and the intense soil and water loss, there are extreme difficulties in vegetation restoration in this area and no great breakthrough has ever been achieved on studies of revegetation over the last several decades. Through over ten years’ research conducted in the typical areas-the Yuanmou dry-hot valley, the authors found that the lithologic property is one of the crucial factors determining soil moisture conditions and vegetation types in the dry-hot valley, and the rainfall infiltration capability is also one of the key factors affecting the tree growth. Then the revegetation zoning based on different slopes was conducted and revegetation patterns for different zones were proposed. 展开更多
关键词 REVEGETATION lithologic property soil moisture plant growth dry-hotvalley Jinsha River
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Surface Morphology of Soil Cracks in Yuanmou Dry-hot Valley Region,Southwest China 被引量:7
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作者 XIONG Donghong LONG Yi +3 位作者 YAN Dongchun LU Xiaoning JI Zhonghua FANG Haidong 《Journal of Mountain Science》 SCIE CSCD 2009年第4期373-379,共7页
Surface morphology of soil cracks is one of the important factors influencing the water evaporation rate in cracked soil in Yuanmou Dry-hot Valley Region,Southwest China. Quantitative study of the complicated surface ... Surface morphology of soil cracks is one of the important factors influencing the water evaporation rate in cracked soil in Yuanmou Dry-hot Valley Region,Southwest China. Quantitative study of the complicated surface morphology of soil cracks is a prerequisite for further studies of soil-cracking mechanisms. The present paper establishes a quantitative indicator system by application of concepts and methods originating from Fractal Geometry and Network Analysis. These indicators can effectively express the complicated features of soil-crack network structure. Furthermore,a series of values related to soil-crack morphology was obtained by image processing on field photos of soil-crack quads,and gradation criteria for the degree of development of soil cracks were determined. Finally,the changes in values of the morphological indicators under different degrees of development were analyzed in detail. Our results indicate that (1) the degree of development of soil cracks can be divided into five grades,i.e.,feeble development,slight development,medium development,intensive development and extremely intensive development; (2) the values of the indicators change predictably with increasing degree of development of soil cracks. The area density (Dc) increases,and both the area-weighted mean ratio of crack area to perimeter (AWMARP),which reflects the intensity of cracking,and the index r,which is related to the connectivity of a soil crack,grow uniformly (albeit with different forms). AWMRAP increases at a geometric rate while r shows logarithm-mic growth,indicating a gradual increase in theconnectivity of a soil crack. Nevertheless,the area-weighted mean of soil-crack fractal dimension (AWMFRAC) shows a decreasing trend,indicating a gradual decline in the complexity of cracks as area density increases. 展开更多
关键词 Soil crack Surface morphology Quantitative indicator Degree of development Southwest China
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Simulation of Morphological Development of Soil Cracks in Yuanmou Dry-hot Valley Region, Southwest China 被引量:8
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作者 XIONG Donghong YAN Dongchun +4 位作者 LONG Yi LU Xiaoning HAN Jianning HAN Xueqin SHI Liangtao 《Chinese Geographical Science》 SCIE CSCD 2010年第2期112-122,共11页
Soil cracking is an important process influencing water and solutes transport in the Yuanmou Dry-hot Valley region of Southwest China. Studying the morphological development of soil cracks helps to further reveal the ... Soil cracking is an important process influencing water and solutes transport in the Yuanmou Dry-hot Valley region of Southwest China. Studying the morphological development of soil cracks helps to further reveal the close relationship between the soil cracking process and water movement in such semi-arid regions. Here we report regular changes on surface morphology of soil cracks with decreasing water in four different soils (Typ-Ustic Ferrisols,Ver-Ustic Ferrisols,Tru-Ustic Vertisols and Typ-Ustic Vertisols) through simulation experiments. Our results indicate the following: 1) Different soils ultimately have different development degrees of soil cracks,according to their various values of crack area density. Soil cracks in Typ-Ustic Ferrisols can only develop to the feeble degree,while those in the other three soils are capable of developing into the intensive degree,and even into the extremely intensive degree. 2) Soil crack complexity,as expressed by the value of the area-weighted mean of crack fractal dimension (AWMFRAC),is found to continuously decrease as a whole through the whole cracking process in all the studied soils. 3) Soil crack connectivity shows a uniform trend in the studied soils,that is to say,connectivity gradually increases with soil crack development. 展开更多
关键词 soil cracks morphological development simulation experiment Yuanmou Dry-hot Valley region Southwest China
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Morphology and controlling factors of the longitudinal profile of gullies in the Yuanmou dry-hot valley 被引量:3
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作者 DING Lin QIN Fa-chao +6 位作者 FANG Hai-dong LIU Hui ZHANG Bin SHU Cheng-qiang DENG Qing-chun LIU Gang-cai YANG Qian-qian 《Journal of Mountain Science》 SCIE CSCD 2017年第4期674-693,共20页
The morphology of the gully longitudinal profile (GLP) is an important topographic index of the gully bottom associated with the evolution of the gullies. This index can be used to predict the development trend and ... The morphology of the gully longitudinal profile (GLP) is an important topographic index of the gully bottom associated with the evolution of the gullies. This index can be used to predict the development trend and evaluate the eroded volumes and soil losses by gullying. To depict the morphology of GLP and understand its controlling factors, the Global Positioning System Real-time Kinematic (GPS RTK) and the total station were used to measure the detail points along the gully bottom of 122 gullies at six sites of the Yuanmou dry-hot Valley. Then, nine parameters including length (Lt), horizontal distance (Dh), height (H), vertical erosional area (A), vertical curvature (Co), concavity (Ca), average gradient (Ga), gully length-gradient index (GL), normalized gully length-gradient index (Ngl), were calculated and mapped using CASS, Excel and SPSS. The results showed that this study area is dominated by slightly concave and medium gradient GLPs, and the lithology of most gullies is sandstone and siltstone. Although different types of GLPs appear at different sites, all parameters present a positively skewed distribution. There are relatively strong correlations between several parameters: namely Lt and H, Dh and H, Lt and A, Dh and A, H and GL. Most GLPs, except three, have a best fit of exponential functions with quasi- straight shapes. Soil properties, vegetation coverage, piping erosion and topography are important factors to affect the GLP morphology. This study provides useful insight into the knowledge of GLP morphology and its influential factors that are of critical importance to prevent and control gully erosion. 展开更多
关键词 Gully longitudinal profile Morphological characteristics Soil erosion Gully erosion Controlling factors Dry-hot valley
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A novel model to assess soil productivity in the dry-hot valleys of China 被引量:3
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作者 DUAN Xing-wu HAN Xu +2 位作者 HU Jin-ming FENG De-tai RONG Li 《Journal of Mountain Science》 SCIE CSCD 2017年第4期705-715,共11页
Accurate evaluation of soil productivity has been a long-standing challenge. Although numerous models for productivity assessment exist, most are cumbersome to use and require substantial parameter inputs. We develope... Accurate evaluation of soil productivity has been a long-standing challenge. Although numerous models for productivity assessment exist, most are cumbersome to use and require substantial parameter inputs. We developed a new empirical soil productivity model based on field investigations of soil erosion, soil physieoehemieal properties, and crop yields in the dry-hot valleys (DHVs) in China. We found that soil pH, and organic matter and available potassium contents significantly affected crop yields under eroded conditions of the DHVs. Moreover, available potassium content was the key factor affecting soil productivity. We then modified an existing soil productivity model by adding the following parameters: contents of effective water, potassium, organic matter, and clay, soil pH, and root weighting factor. The modified soil productivity model explained 63.5% of the crop yield. We concluded that the new model was simple, realistic, and exhibited strong predictability. In addition to providing an accurate assessment of soil productivity,our model could potentially be applied as a soil module in comprehensive crop models. 展开更多
关键词 Soil productivity Productivity indexmodel Redundancy analysis Dry-hot valleys
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Impacts of reforestation on woody species composition,species diversity and community structure in dry-hot valley of the Jinsha River,southwestern China
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作者 GONG Zhi-lian TANG Ya 《Journal of Mountain Science》 SCIE CSCD 2016年第12期2182-2191,共10页
To understand the impacts of reforestation on woody species composition,species diversity and community structure,seven plantation forests in dryhot valley of the Jinsha River in Southwest China were investigated,with... To understand the impacts of reforestation on woody species composition,species diversity and community structure,seven plantation forests in dryhot valley of the Jinsha River in Southwest China were investigated,with adjacent wastelands,natural shrub grassland and a natural forest as references.Species importance value,species richness,species heterogeneity and Sorenson similarity index between plantations and the natural forest were analyzed.Results indicated that compared to wastelands and natural shrub grassland,reforestation improved species diversity and community structure,and more forest woody species found suitable habitats in plantations.Species diversity in understory of plantations and Sorenson similarity index were significantly negatively correlated with stem density in mature plantations(26-31 years old).Higher species diversity and Sorenson similarity index existed in mature sparse plantations due to lower stem density and more tree species planted initially.In contrast,reference natural forest,with species heterogeneity of 2.28 for shrub layer,showed the highest species diversity.It would take a long time for species composition and diversity to recover through reforestation in a dry-hot valley.Therefore,it was essential to protect remnant natural forests strictly and reforest with suitable management such as lower stem density and increasing genetic diversity of trees planted. 展开更多
关键词 Biodiversity Plantations Dry hot valley Genetic resources Natural forest Reforestation
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