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基于Landsat8的凤永高速地表温度反演
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作者 罗闰豪 何伟 王瑞雪 《地下水》 2024年第3期7-10,19,共5页
在隧道建设过程中,高地温热害会影响机械设备效率和施工进度,还会恶化作业环境、对人员安全造成威胁,因此,精准识别地热异常区对隧道建设非常重要。热红外遥感是用遥感的方法探测地球表面的温度,以此为基础利用遥感技术反演地表温度愈... 在隧道建设过程中,高地温热害会影响机械设备效率和施工进度,还会恶化作业环境、对人员安全造成威胁,因此,精准识别地热异常区对隧道建设非常重要。热红外遥感是用遥感的方法探测地球表面的温度,以此为基础利用遥感技术反演地表温度愈发可靠。以云南省凤永高速凤庆-领岗地隧道为研究区域,采用Landsat8影像数据,运用大气校正法对研究区进行地表温度反演,再利用DEM数据制作地形坡向文件,按阳坡、阴坡分布提取地表温度,结合地质构造对地表温度异常进行分析,圈定地热异常区。 展开更多
关键词 landsat8 地表温度反演 坡向分析 地热异常
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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS 被引量:4
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作者 ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, Chengdu 610066, Sichuan, China 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China +1 位作者 3. Graduate University of the Chinese Academy of Sciences, Beijing 100049, China 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期915-921,共7页
By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of ... By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure. 展开更多
关键词 slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area
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Soil Atterberg Limits and Consistency Indices as Influenced by Land Use and Slope Position in Western Iran 被引量:2
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作者 Zahra ZOLFAGHARI Mohamamd Reza MOSADDEGHI +1 位作者 Shamsollah AYOUBI Hamid KELISHADI 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1471-1483,共13页
Atterberg limits and consistency indices are used for classifications of cohesive(fine-grained) soils in relation with compaction and tillage practices. They also provide information for interpreting several soil mech... Atterberg limits and consistency indices are used for classifications of cohesive(fine-grained) soils in relation with compaction and tillage practices. They also provide information for interpreting several soil mechanical and physical properties such as shear strength, compressibility, shrinkage and swelling potentials. Although, several studies have been conducted regarding the land use effects on various soil mechanical properties, little is known about the effects of land use and slope positions on Atterberg limits and consistency indices. This study was conducted to investigate the effects of land use and slope position on selected soil physical and chemical properties, Atterberg limits and consistency indices in hilly region of western Iran. Three land uses including dryland farming, irrigated farming and pasture and four slope positions(i.e., shoulder, backslope, footslope, and toeslope) were used for soil samplings. One hundred eleven soil samples were collected from the surface soil(0-10 cm). Selected physical and chemical properties, liquid limit(LL), plastic limit(PL) and shrinkage limit(SL) were measured using the standard methods; and consistency indices including plastic index(PI), friability index(FI), shrinkage index(SI) and soil activity(A=PI/clay) were calculated. The results showed that irrigated farming significantly increased organic matter content(OM) and OM/clay ratio, and decreased bulk density(ρb) and relative bulk density(ρb-rel) as a result of higher biomass production and plant residues added to the soil compared to other land uses. Except for sand content, OM, ρb, cation exchange capacity(CEC) and calcium carbonate equivalent(CCE), slope position significantly affected soil physical and chemical properties. The highest values of silt, OM/clay and CEC/clay were found in the toeslope position, predominantly induced by soil redistribution within the landscape. The use of complexed(COC)- noncomplexed organic carbon(NCOC) concept indicated that majority of the studied soils were located below the saturation line and the OM in the soils was mainly in the COC form. The LL, PI, FI and A showed significant differences among the land uses; the highest values belonged to the irrigated farming due to high biomass production and plant residues returned to the soils. Furthermore, slope position significantly affected the Atterberg limits and consistency indices except for SL. The highest values of LL, PI, SI and A were observed in the toeslope position probably because of higher OM and CEC/clay due to greater amount of expandable phyllosilicate clays. Overall, soils on the toeslope under irrigated farming with high LL and SI and low values of FI need careful tillage management to avoid soil compaction. 展开更多
关键词 land use slope position Atterberg limits Soil consistency Relative bulk density Complexed organic carbon
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Soil Organic Carbon Pools in Particle-Size Fractions as Affected by Slope Gradient and Land Use Change in Hilly Regions,Western Iran 被引量:12
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作者 Parisa Mokhtari KARCHEGANI Shamsollah AYOUBI +1 位作者 Mohammad Reza MOSADDEGHI Naser HONARJOO 《Journal of Mountain Science》 SCIE CSCD 2012年第1期87-95,共9页
This study was conducted to explore the effects of topography and land use changes on particulate organic carbon(POC),particulate total nitrogen(PTN),organic carbon(OC) and total nitrogen(TN) associated with different... This study was conducted to explore the effects of topography and land use changes on particulate organic carbon(POC),particulate total nitrogen(PTN),organic carbon(OC) and total nitrogen(TN) associated with different size primary particle fractions in hilly regions of western Iran.Three popular land uses in the selected site including natural forest(NF),disturbed forest(DF) and cultivated land(CL) and three slope gradients(0-10 %,S1,10-30 %,S2,and 30-50%,S3) were employed as the basis of soil sampling.A total of 99 soil samples were taken from the 0-10 cm surface layer in the whole studied hilly region studied.The results showed that the POC in the forest land use in all slope gradients was considerably more than the deforested and cultivated lands and the highest value was observed at NF-S1 treatment with 9.13%.The values of PTN were significantly higher in the forest land use and in the down slopes(0.5%) than in the deforested and cultivated counterparts and steep slopes(0.09%) except for the CL land use.The C:N ratios in POC fraction were around 17-18 in the forest land and around 23 in the cultivated land.In forest land,the silt-associated OC was highest among the primary particles.The enrichment factor of SOC,EC,was the highest for POC.For the primary particles,EC of both primary fractions of silt and clay showed following trend for selected land uses and slope gradients:CL> DF> NF and S3 > S2> S1.Slope gradient of landscape significantly affected the OC and TN contents associated with the silt and clay particles,whereas higher OC and TN contents were observed in lower positions and the lowest value was measured in the steep slopes.Overall,the results showed that native forest land improves soil organic carbon storage and can reduce the carbon emission and soil erosion especially in the mountainous regions with high rainfall in west of Iran. 展开更多
关键词 land use change Soil organic carbon slope gradient Physical fractionation Particulate organic carbon
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Water Availability for Winter Wheat Affected by Summer Fallow Tillage Practices in Slope Dryland
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作者 WANGXiao-bin CAIDian-xiong +9 位作者 JINKe WUHui-jun BAIZhan-guo ZHANGCan-jun YAOYu-qing LUJun-jiez WANGYu-hong YANGBo RogerHartmann DonaldGabriels 《Agricultural Sciences in China》 CAS CSCD 2003年第7期773-778,共6页
The tillage experiments for winter wheat were conducted on the slope farmland in Luoyang, Henan Province in the semihumid to arid loess plateau areas of North China. Different tillage methods including reduced tillage... The tillage experiments for winter wheat were conducted on the slope farmland in Luoyang, Henan Province in the semihumid to arid loess plateau areas of North China. Different tillage methods including reduced tillage(RT), no-till(NT), 2 crops/year(2C), subsoiling(SS), and conventional tillage(CT)were compared to determine the effects of tillage methods on soil water conservation, water availability, and wheat yields in a search for better farming systems in the areas. The NT and SS showed good effects on water conservation. The soil water storage increased 12 - 33 mm with NT and 9-24 mm with SS at the end of summer fallow periods. The soil evaporation with NT and SS decreased 7-8 mm and 34 - 36 mm during the fallow periods of 1999 and 2001, respectively. Evapotranspiration(ET)with NT and SS increased about 47 mm during wheat growth periods of 2000 to 2001. Treatment RT and 2C had low water storage and high water losses during the fallow periods. The winter wheat yields with conservation tillage practices were improved in the 2nd year, increased by 3, 5 and 8% with RT, NT and SS, respectively, compared with CT. The highest wheat yields were obtained with subsoiling, and the maximum economic benefits from no-till. All conservation tillage practices provided great benefits to saving energy and labors, reducing operation inputs, and increasing economic returns. No-till and subsoiling have shown promise in increasing water storage, reducing water loss, enhancing water availability, and saving energy, as well as increasing wheat yield. 展开更多
关键词 DRYland slope land Conservation tillage NO-TILL SUBSOILING Soil water
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Construction of Forest and Grass Industry Economic Belt Using Land Resources in Road Side Slope 被引量:1
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作者 Zhaohua ZHU Qingwang LAI +2 位作者 Guogang XU Guoliang CHI Xiaorong CHEN 《Asian Agricultural Research》 2017年第7期70-75,79,共7页
The construction of expressway and high-speed rail is at the sacrifice of the soil ecological environment. It brings about much damaged land and bare slope. It is necessary to restore vegetation and rebuild landscape.... The construction of expressway and high-speed rail is at the sacrifice of the soil ecological environment. It brings about much damaged land and bare slope. It is necessary to restore vegetation and rebuild landscape. In the design of target plant community and configuration plants,it is required to select as far as possible plants that can blossom and bear fruit or pods. Then seeds of these plants can be harvested,processed and sold,and applied for other projects,so as to develop into a complete forest and grass seed industry chain. This not only reasonably utilizes land resources,but also provides a new approach to the problem of insufficient fine forest seed sources in China. This paper discussed the use of land resources in road side slope and forest and grass seed selection and breeding technology,and elaborated the industrialized development paths for forest and grass seed industries in road side slope. Finally,it arrived at following recommendations.( i) The construction of forest and grass industry economic belt using land resources in road side slope can realize maximum land value. Building a road can help people there get rich,and the type of land and water cultivates its type of forest and grass.( ii) It can make up for the losses incurred from construction of expressway and high-speed rail or destroying forest land,and it can increase farmers' income.( iii) It can increase the supply of domestic seeds,reduce seed import,save foreign exchange,and partly solve the problem of insufficient supply of forest and grass seeds.( iv) It is able to form a complete forest and grass seed industry economic cycle chain,increase employment,and provide new approaches for enriching and benefiting farmers. 展开更多
关键词 Road side slope land resources Forest and grass species Forest and grass seed industry economic belt
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Sustainable land-use patterns for arid lands: A case study in the northern slope areas of the Tianshan Mountains 被引量:6
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作者 LUO Geping FENG Yixing +1 位作者 ZHANG Baiping CHENG Weiming 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期510-524,共15页
Sustainable land use patterns are ecological and economic prerequisites of regional sustainable development. This is especially true for arid lands, where the environment is wholly fragile thanks to extremely limited ... Sustainable land use patterns are ecological and economic prerequisites of regional sustainable development. This is especially true for arid lands, where the environment is wholly fragile thanks to extremely limited precipitation, and where human activities have greatly transformed natural desert system by clearing natural vegetation, expanding oases and even building dams on inland rivers. However, the current studies on land use patterns are still characterized by field investigations and case studies, with almost no solid scientific basis. This paper holds that land types and their combination patterns are the principal basis for designing sustainable land use patterns, and that GIS and RS-based large-scale land type mapping and the study of their spatial combination structures should be coordinated with the demand of social development. The existing environmental problems induced by irrational land use mostly result from their deviation from the natural properties of land types. Taking the northern slope of the Tianshan Mountains (NSTM) as an example and considering land type patterns as the basis of land use patterns, this paper improves the vertical oa- sis-and-mid-mountain two-belts development model and the sustainable mountain land use model for arid lands put forward in recent years; and in terms of oases patterns, it outlines oasis development models, including intensive land use pattern in alluvial-diluvial fans, moderate agricultural development pattern in alluvial plains, and ecological land use pattern in river-end oases. 展开更多
关键词 northern slope of the Tianshan Mountains land type land-use pattern oases
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Interactions between water-land resources and oasis urban development at the northern slopes of the Tianshan Mountains,Xinjiang,China 被引量:9
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作者 Jun LEI Wen DONG +2 位作者 Yu YANG Jie LU Thomas STERR 《Journal of Arid Land》 SCIE 2012年第2期221-229,共9页
Urban development in arid and semi-arid regions is largely constrained by fragile physical environ- ments. The characteristics of an urban settlement are different from those in other regions of China. This paper anal... Urban development in arid and semi-arid regions is largely constrained by fragile physical environ- ments. The characteristics of an urban settlement are different from those in other regions of China. This paper analyses the coupling characteristics and spatio-temporal variations for oasis urban development and water-land resources at the northern slopes of the Tianshan Mountains by principal component analysis and a coupling degree model. The result shows that the degree and change in regional use of water and land resources are different among the studied cities/counties during their development. The built-up areas of these cities/counties have changed little with increasing populations and urbanization levels, which well reflects that the urban development in arid and semi-arid regions is limited by oasis areas. Per capita amount of water supplied, however, presented a trend of slowed growth with increasing levels of urbanization. Water consumption gradually increased with urban development and the improvement of people's living standards, accompanied by enhanced water use efficiency. The level of urbanization can be assessed through the coupling degree between oasis urban development and the use of water and land resources. A high coupling degree represents a high level of comprehensive urban devel- opment and use of water-land resources. Alternatively, a low coupling degree denotes a low level of urban devel- opment and water-land resource use. 展开更多
关键词 oasis urban development water-land resources coupling factors coupling degree northern slopes of the TianshanMountains
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Landscape Ecological Security Assessment of Low-Slope Hilly Region in Lu County,China
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作者 王旭熙 彭立 +1 位作者 苏春江 徐定德 《Journal of Donghua University(English Edition)》 EI CAS 2017年第3期466-474,共9页
Low-slope hilly land( LSHL) refers to regions with relatively lower altitude,smaller topographic changes and gentler slopes. Exploitation and utilization of such areas is acting as an efficient approach to release the... Low-slope hilly land( LSHL) refers to regions with relatively lower altitude,smaller topographic changes and gentler slopes. Exploitation and utilization of such areas is acting as an efficient approach to release the intensity in land utilization for mountainous areas in China, and needs further study. By summarizing related domestic concepts regarding LSHL,and taking Lu County of Sichuan province as the sample,this paper defined the scope of LSHL and extracted a total coverage of 331. 71 km2 LSHL.Then based on the landscape ecological security patterns theory,we have established the landscape ecological security pattern of Lu County by the minimum cumulative resistance model,targeting to achieve ecological land protection. Moreover,LSHL of different landscape security levels is further classified through overlay analysis on the current utilization status of the LSHL. The LSHL is classified into four categories, including prioritized development type,moderate development type, limited development type and prohibited development type. Their scopes of areas are 108. 72,97. 03,68. 36 and 57. 60 km2 respectively. In addition,respective land utilization and exploitation plan for LSHL are proposed according to the analysis of characteristics of each type. The result has provided scientific references for the definition,establishment of landscape ecological security pattern as well as the appropriate exploitation and utilization of the LSHL. 展开更多
关键词 landscape exploitation mountainous coverage hilly overlay altitude targeting moderate cultivated
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中国西南地区旱坡地碳减排研究进展与展望
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作者 王谢 杨琴 +7 位作者 刘禹池 李芹 杨勤 陈冠陶 岳丽杰 张建华 陈新平 刘永红 《作物学报》 CAS CSCD 北大核心 2024年第7期1635-1646,共12页
农田生态系统既是碳源,又是碳汇,具备很强的减排固碳潜力,对全球碳循环贡献巨大。西南地区旱坡地长期小规模、碎片化的农业生产方式给区域碳排放带来极大的不确定性。探索西南旱坡地的碳排放特征和减排途径对于改善环境、提升区域农业... 农田生态系统既是碳源,又是碳汇,具备很强的减排固碳潜力,对全球碳循环贡献巨大。西南地区旱坡地长期小规模、碎片化的农业生产方式给区域碳排放带来极大的不确定性。探索西南旱坡地的碳排放特征和减排途径对于改善环境、提升区域农业生产潜力具有重要意义。本研究系统总结了我国西南地区旱坡地农田生态系统主要温室气体(CO_(2)、N_(2)O)的产生环节,探讨了旱坡地固碳减排新材料与新技术的应用效果,提出了未来西南地区旱坡地的固碳减排策略。(1)鉴于西南地区旱坡地的区域资源禀赋、产业基础、生产规模、经营方式、生态功能等差异巨大,应结合地区特殊的农业生产条件,集成研发适宜的固碳减排措施和监测体系,探索全球变暖背景下西南旱坡地碳排放过程及其内在机制,以全面提升地区农业生产应对气候变化的韧性。(2)鉴于西南地区农作物复种指数较高且作物空间分布斑块化,应依据国家战略和地方规划,以绿色高产优质为目标导向,改进农业生产方式,优化产业空间布局。(3)由于西南地区旱坡地碳减排是一个复合过程,亟需根据今后较长一段时间内区域农业生产的实际结构和功能需求,有针对性地对各项成熟的减排技术、固碳产品和固碳模式进行优化组合,形成综合性的固碳减排方案。综上,本综述期望为进一步研究西南地区旱坡地农田生态系统的碳源和碳汇特征,以及合理调整农田管理措施提供全面的有效参考。 展开更多
关键词 温室气体 旱坡地 固碳减排 中国西南地区
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表层土壤结构对红壤坡耕地产流及产沙过程的影响 被引量:2
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作者 张紫薇 赵文俊 +5 位作者 李奇 马一淳 田亮 杨广勇 李忠武 刘窑军 《土壤学报》 CAS CSCD 北大核心 2024年第2期434-444,共11页
针对南方红壤区坡耕地水土流失严重与表层结构退化的现状,采用室内模拟降雨的方法,分析表层土壤结构和雨强对降雨再分配、坡面产流及产沙过程的影响。结果表明:(1)表层土壤结构显著改变降雨的再分配过程,深耕作层可以降低地表径流比例,... 针对南方红壤区坡耕地水土流失严重与表层结构退化的现状,采用室内模拟降雨的方法,分析表层土壤结构和雨强对降雨再分配、坡面产流及产沙过程的影响。结果表明:(1)表层土壤结构显著改变降雨的再分配过程,深耕作层可以降低地表径流比例,增加壤中流比例,60和90 mm·h^(-1)雨强下,随耕作层深度增加,地表径流平均比例依次为70.5%,62.9%和56.8%,壤中流平均比例依次提升为7.1%,12.3%和18.1%;(2)土壤流失率随雨强增加而增大,90 mm·h^(-1)雨强下土壤流失率为60 mm·h^(-1)雨强下的4.4倍,土壤流失率随耕作层深度增加而显著减小,依次为36.8、21.1和13.1 g·m^(-2) min^(-1);(3)雨强和表层土壤结构显著影响坡面侵蚀形态的演变,随耕作深度增加坡面侵蚀由细沟侵蚀逐渐转变为面蚀。表层土壤结构显著改变坡耕地降雨-径流关系和侵蚀过程,合理增加耕作层深度,对降低地表侵蚀、促进土壤水分的深层下渗、增加土壤深层持水量具有积极作用。 展开更多
关键词 土壤结构 产流 产沙 壤中流 红壤坡耕地
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石漠化坡地不同整地措施下表层土壤水分空间分布特征 被引量:1
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作者 田卓 张帅普 徐勤学 《水土保持学报》 CSCD 北大核心 2024年第4期335-345,共11页
[目的]分析石漠化坡地不同整地措施下表层土壤水分的空间分布特征,为提高石漠化坡地的水资源利用效率和农业管理水平提供参考依据。[方法]以石漠化坡地中反坡、斜坡和平地3种整地措施下的柑橘林地为研究对象,采用经典统计学、地统计学... [目的]分析石漠化坡地不同整地措施下表层土壤水分的空间分布特征,为提高石漠化坡地的水资源利用效率和农业管理水平提供参考依据。[方法]以石漠化坡地中反坡、斜坡和平地3种整地措施下的柑橘林地为研究对象,采用经典统计学、地统计学和多重分形理论研究土壤水分的空间分布特征。[结果](1)反坡的土壤含水量显著高于平地和斜坡(p<0.05),平地土壤含水量的空间连续性和聚集性以及总变异和结构性变异强于斜坡和反坡。(2)不同整地措施下的土壤含水量均具有中等强度变异性(10.00%≤CV≤100.00%)、强空间自相关性[C_(0)/(C_(0)+C)≤0.25]和极显著(p<0.01)的空间聚集性。(3)不同整地措施下的土壤含水量分布具有多重分形特征,旱季时反坡的土壤含水量分布区间最窄,斜坡的土壤含水量分布更离散;雨季时平地的土壤含水量分布区间最窄,反坡的土壤含水量更不均匀。[结论]土壤机械组成是影响土壤含水量的主要因素,反坡整地措施更有利于改善石漠化坡地的土壤水分条件。 展开更多
关键词 石漠化坡地 整地措施 土壤水分 空间分布
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三峡库区乡村坡耕地长时间序列动态演变与转型
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作者 赵雯欣 陈艳 +2 位作者 李阳兵 王清荣 邵景安 《生态学报》 CAS CSCD 北大核心 2024年第16期6907-6922,共16页
研究山区坡耕地动态演变与利用转型,对中国西南山区传统乡村的粮食安全和农业可持续发展具有一定指导意义。以三峡库区腹地草堂溪流域为研究对象,利用ArcGIS 10.2软件并结合Fragstats、土地利用转移矩阵等技术手段对坡耕地的演变和驱动... 研究山区坡耕地动态演变与利用转型,对中国西南山区传统乡村的粮食安全和农业可持续发展具有一定指导意义。以三峡库区腹地草堂溪流域为研究对象,利用ArcGIS 10.2软件并结合Fragstats、土地利用转移矩阵等技术手段对坡耕地的演变和驱动机制进行分析。结果表明:(1)坡耕地面积持续减少,与1965年相比,2020年坡耕地面积减少8004.7 hm^(2),整体动态度达7.21%,随着社会经济的发展坡耕地动态演变更趋活跃;坡耕地面积随高程级、坡度级的增加而先增后减,随聚落距离的增加而迅速减少。(2)坡耕地LPI、MPS、AI呈减小的趋势,MNN不断增加;坡耕地规模减小、破碎化程度加剧,斑块连片集中化程度减弱。(3)坡耕地主要向果园、林地和草地等转换,坡耕地生产功能主要转换为生态经济功能和生态功能,部分转换为生活功能。(4)山区坡耕地动态演变和利用转型可以归纳为生态经济型、撂荒型和生态型3种模式,其演变主要受到自然、社会经济、政策等多种因素的共同作用。研究结果揭示了50多年来三峡库区坡耕地的动态演变及转型特征,对库区山区农村土地利用、乡村可持续发展以及人地关系的改善具有启示意义。 展开更多
关键词 土地利用 坡耕地 动态演变 三峡库区
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Error Analysis on Gradient Information of Sloping Land Derived from the Low-resolution DEM 被引量:6
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作者 王莉 贺秀斌 +2 位作者 鲍玉海 南宏伟 刘艳锋 《Agricultural Science & Technology》 CAS 2010年第1期109-112,共4页
With digital elevation model (DEM),sloping data were extracted automatically and soil erosion situation was also investigated. Compared with field survey and the related studies,the results showed that parallel rang... With digital elevation model (DEM),sloping data were extracted automatically and soil erosion situation was also investigated. Compared with field survey and the related studies,the results showed that parallel range-gorge landform in Three Gorges reservoir area,the inter-bedded structures formed by Jurassic purple clay (page) rocks and human activities were the key controlling factors for small-scale sloping terrain. 展开更多
关键词 Sloping land Resolution of DEM land use Soil erosion
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高原湖泊流域建设用地坡谱演变研究--以滇池流域为例
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作者 马腾 段学军 +3 位作者 王佳恒 颜蔚 闵敏 邹辉 《地理科学》 CSCD 北大核心 2024年第7期1142-1152,共11页
高原湖泊流域因受自然地理条件限制较大,建设用地不可避免地出现“向湖”“爬坡”扩张现象,通过构建建设用地坡谱可有效揭示其时空演变规律。以滇池流域为例,基于2000—2020年土地利用数据和基于DEM转化的海拔数据,借助陡峭度、均匀度... 高原湖泊流域因受自然地理条件限制较大,建设用地不可避免地出现“向湖”“爬坡”扩张现象,通过构建建设用地坡谱可有效揭示其时空演变规律。以滇池流域为例,基于2000—2020年土地利用数据和基于DEM转化的海拔数据,借助陡峭度、均匀度、上限坡度等方法分析了坡谱演化特征,提出了加权爬坡指数(WBCI)以定量表征建设用地爬坡程度,并结合海拔区间的视角探究了建设用地扩张的空间分异及演变规律。结果表明:①滇池流域建设用地扩张显著,呈现以滇池北岸主城区为主核心,东岸呈贡区、南岸晋宁区为次核心的建设用地分布格局;②建设用地垂直空间扩张呈现两阶段特征,即先平地扩张后爬坡扩张。2000—2015年为向湖、降海拔扩张阶段(WBCI<0);2015—2020为爬坡、升海拔扩张阶段(WBCI>0)。③建设用地坡谱演变与海拔变化在流域尺度具有一致性,即爬坡指数变化趋势与建设用地分布的平均海拔变化趋势高度一致。但在区县尺度,建设用地爬坡扩张与海拔爬升存在明显的空间差异性。研究为城镇空间二维扩展向三维扩展提供新的思考和视角,也可为城镇空间用地规划及其生态环境效应评估提供支撑借鉴。 展开更多
关键词 建设用地扩张 坡谱分析 地形梯度 海拔分区 滇池流域
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不同农作措施下紫色土坡耕地氮磷流失特征
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作者 李清藐 李天阳 +1 位作者 何丙辉 张海香 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期46-54,共9页
为揭示不同农作措施下径流氮磷流失变化特征,基于2020年12场次的自然降雨产流事件,分析了顺坡无施肥(对照,CK)、顺坡混合施用有机肥和化肥(T1)、顺坡单施化肥(T2)、顺坡单施化肥增量(T3)、横坡单施化肥(T4)5种处理下径流量及径流中总氮(... 为揭示不同农作措施下径流氮磷流失变化特征,基于2020年12场次的自然降雨产流事件,分析了顺坡无施肥(对照,CK)、顺坡混合施用有机肥和化肥(T1)、顺坡单施化肥(T2)、顺坡单施化肥增量(T3)、横坡单施化肥(T4)5种处理下径流量及径流中总氮(TN)、总磷(TP)质量浓度与流失量、氮磷比(TN/TP)的变化特征.结果表明:①各处理径流TN,TP最高质量浓度均发生在施肥后的前6次降雨,其中的4次降雨事件造成了超50%的总氮、总磷流失.②与单施化肥相比,有机肥化肥配施的径流TN,TP流失量没有显著差异,且径流TN,TP质量浓度与施肥后天数都呈极显著线性负相关(p<0.01).③和顺坡耕作相比,横坡垄作可以显著削减76.85%的径流量、75.12%的径流总氮流失量和87.97%的径流总磷流失量.④CK处理的TN/TP显著高于T2和T3(p<0.05),但与T1,T4差异无统计学意义(p>0.05),所有处理下全年超50%的TN/TP≥50,表现为磷限制. 展开更多
关键词 地表径流 氮磷流失 坡耕地 紫色土
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侵蚀性降雨对黑土坡耕地土壤侵蚀特征的影响
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作者 丁贵惠 任忠政 +2 位作者 胡伟 陈渊 张兴义 《水土保持学报》 CSCD 北大核心 2024年第2期47-56,共10页
[目的]降雨是黑土坡耕地水力侵蚀的动力来源,研究天然降雨条件下坡耕地土壤侵蚀特征对水土流失防治具有重要意义。[方法]基于黑龙江省海伦市光荣小流域2021-2022年不同坡度(3°,5°和7°)顺坡垄作径流小区观测的43场次侵蚀... [目的]降雨是黑土坡耕地水力侵蚀的动力来源,研究天然降雨条件下坡耕地土壤侵蚀特征对水土流失防治具有重要意义。[方法]基于黑龙江省海伦市光荣小流域2021-2022年不同坡度(3°,5°和7°)顺坡垄作径流小区观测的43场次侵蚀性降雨事件,采用K-Mean聚类法对比分析不同雨型和坡度下径流与输沙特征,并探讨影响坡耕地径流与输沙的影响因素。[结果]研究区以短历时、大雨强、小雨量的降雨(雨型3)为主,其次是中等历时、中等雨强、中等雨量的降雨(雨型2),长历时、小雨强、大雨量的降雨(雨型1)极少发生。相同雨型下,累积径流深和输沙量均随坡度的增加而增大。相同坡度下,不同雨型对累积径流深响应不同,累积输沙量整体表现为雨型3贡献最高(50.90%~57.90%),雨型2次之(37.60%~44.10%),雨型1最低。雨型2事件降雨侵蚀力和坡度对径流深产生直接影响,径流深和坡度对输沙量产生直接影响。雨型3事件降雨侵蚀力通过直接和间接作用影响径流深,进而影响输沙量。[结论]对所有雨型事件,降雨侵蚀力和坡度是影响坡耕地径流深的主控因子,径流深和坡度是影响坡耕地输沙量的主控因子。 展开更多
关键词 雨型 坡度 黑土 坡耕地 土壤侵蚀
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冀北山地植被恢复对不同坡位土壤可蚀性与养分的影响
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作者 沙晓玮 武昱鑫 +1 位作者 贾国栋 余新晓 《水土保持学报》 CSCD 北大核心 2024年第4期11-19,28,共10页
[目的]了解不同坡位和不同土地利用引起的土壤可蚀性和养分差异,讨论各因素对土壤可蚀性和养分情况的影响状况。[方法]通过土壤和根系取样,使用加权求和法计算不同坡位和不同土地利用下的综合土壤可蚀性指数(CSEI)和综合土壤养分指数(CS... [目的]了解不同坡位和不同土地利用引起的土壤可蚀性和养分差异,讨论各因素对土壤可蚀性和养分情况的影响状况。[方法]通过土壤和根系取样,使用加权求和法计算不同坡位和不同土地利用下的综合土壤可蚀性指数(CSEI)和综合土壤养分指数(CSNI)。[结果](1)不同坡位下的CSEI和CSNI均存在差异,其中CSEI的最大、最小值分别出现在坡上(0.653)和坡下(0.275),CSNI的最大、最小值分别出现在坡顶(0.715)和坡上(0.341);(2)不同土地利用下的CSEI和CSNI均存在差异,其中CSEI的最大、最小值分别出现在撂荒地(0.617)和林地(0.252),CSNI的最大、最小值分别出现在林地(0.793)和撂荒地(0.322);(3)CSEI与黏粒含量、砂粒含量、根长密度和地上生物量呈显著负相关,与粉粒含量和土壤容重呈显著正相关,其中容重的直接影响最大(0.26);CSNI与黏粒含量、砂粒含量、根长密度和地上生物量呈显著正相关,与粉粒含量和土壤容重呈显著负相关,其中黏粒含量的直接影响最大(0.45);CSEI、CSNI二者间呈显著负相关。[结论]坡位对CSEI和CSNI均有显著影响,在植被恢复中应注重坡上和坡中;各地貌部位植被恢复均有效降低CSEI并提升CSNI,其中乔木对水土流失的控制更为有效。 展开更多
关键词 土壤可蚀性 土壤养分 坡位 土地利用
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不同作物种植对光伏坡地土壤团聚体稳定性与有机碳的影响
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作者 李馨妤 孙东滨 +5 位作者 张孟豪 林晓钦 钟鹤森 庞煜龚 周波 张池 《农业环境科学学报》 CAS CSCD 北大核心 2024年第7期1549-1556,共8页
为探讨种植不同作物对坡地土壤团聚体分布及其有机碳含量变化特征的影响,在光伏农业坡地项目区内采集玉米、大豆、南瓜片区以及未种植区土壤样品(各处理分别记作YM、DD、NG、CK),测定不同片区的土壤机械稳定性团聚体和水稳定性团聚体的... 为探讨种植不同作物对坡地土壤团聚体分布及其有机碳含量变化特征的影响,在光伏农业坡地项目区内采集玉米、大豆、南瓜片区以及未种植区土壤样品(各处理分别记作YM、DD、NG、CK),测定不同片区的土壤机械稳定性团聚体和水稳定性团聚体的分布特征及其不同粒径(d>2 mm、0.25 mm≤d≤2 mm、d<0.25 mm)团聚体的有机碳含量,计算土壤团聚体破坏率,同时对土壤团聚体分布比例及其有机碳含量进行相关性分析。结果表明:与CK相比,种植活动使土壤的机械稳定性和水稳定性大团聚体分布比例显著降低,其破坏率显著升高(P<0.05);而不同作物之间,土壤的团聚体破坏率表现为玉米>大豆>南瓜(P<0.05),YM、DD较NG处理显著提高了44.2%和23.1%。与CK相比,种植区土壤有机碳及水稳定大团聚体有机碳的含量显著降低(P<0.05);不同作物处理之间,NG处理的有机碳含量分别显著高于YM和DD处理19.3%和15.4%,且其不同粒级团聚体有机碳含量也显著高于YM和DD处理(P<0.05)。相关性分析结果显示,水稳定性大团聚体分布比例与土壤有机碳含量呈显著正相关(P<0.05),与团聚体破坏率呈显著负相关,而微团聚体情况则相反(P<0.05)。研究表明,光伏农业坡地项目区种植作物造成土壤团聚体破坏及有机碳流失,但不同作物品种对其影响不同,其中南瓜种植对土壤扰动和有机碳流失的影响最小,是光伏农业坡地项目区的优选作物。另外,为了缓解项目区土壤团聚体破坏及有机碳流失,应补充土壤有机质,采取保护性耕作措施。 展开更多
关键词 光伏农业 坡地 土壤 团聚体 有机碳
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西南旱坡地适栽油菜品种筛选试验
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作者 杨婷婷 田效琴 +2 位作者 李卓 刘永红 李伟 《中国果菜》 2024年第2期54-59,共6页
为筛选出适宜在西南旱坡地种植的高产抗逆油菜品种,选择西南片区市面上具有代表性的21个油菜品种(组合)进行大田试验,分别对抗病性、抗倒性、农艺性状和产量等指标进行综合评价。结果表明,除‘川油36’‘德5油33’外,其余油菜品种均具... 为筛选出适宜在西南旱坡地种植的高产抗逆油菜品种,选择西南片区市面上具有代表性的21个油菜品种(组合)进行大田试验,分别对抗病性、抗倒性、农艺性状和产量等指标进行综合评价。结果表明,除‘川油36’‘德5油33’外,其余油菜品种均具备较好的抗倒性。‘蜀龙油2号油满缸’‘川油83’‘宁杂11号’‘德兴油12号’‘德5油700’抗病性较强;‘蜀龙油2号油满缸’‘川油83’‘宁杂11号’‘德兴油12号’‘川油48’生长势与整齐度较好;‘德兴油12号’‘蜀龙油2号油满缸’农艺性状较优;‘德兴油12号’产量最高,较其余品种增产2.99%~139.72%。综上所述,‘德兴油12号’在生长势、抗逆性、农艺性状和产量等方面综合表现最优,可作为西南旱坡地油菜主导品种大面积种植。 展开更多
关键词 油菜 品种筛选 农艺性状 旱坡地
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