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Land-use changes in the small watershed of the Loess Plateau,hilly-gully region, China 被引量:2
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作者 Yini Han Jianzhi Niu Feizhou Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期91-99,共9页
As more and more farmland is converted to forestry, the need for effective decision support regarding the use of land in the fragile ecological environment of the Loess Plateau hilly-gully area. The Luoyugou watershed... As more and more farmland is converted to forestry, the need for effective decision support regarding the use of land in the fragile ecological environment of the Loess Plateau hilly-gully area. The Luoyugou watershed was chosen as the study area to calculate the single dynamic degree, integrated dynamic degree, and change indexes of land use, as well as the land-use type transition matrix. This was done by interpreting the TM and SPOT images of the Luoyugou watershed in 1986, 1995, and2004 and making statistical analysis. The results of ou statistical analysis show that the conversion of slope farm land to terrace and forest land plays a dominant role in land-use changes in the Luoyugou watershed from 1986 to2004. The land-use changes are mainly driven by popula tion growth, socio-economic development, consume spending, and investment in forest ecology. 展开更多
关键词 loess Plateau hilly-gully region Luoyugou watershed Land use and cover changes Driving force
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Characteristics of Soil Respiration of Terraces and Slope Farmland in Loess Hilly and Gully Regions
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作者 Ma Tao Zhou Bo +2 位作者 Chen Aihua Zhang Feng Dong Yanli 《Meteorological and Environmental Research》 CAS 2017年第1期67-70,共4页
Soil CO_2 emissions of terraces and slope farmland in loess hilly and gully regions were measured by using Infra Red Gas Analysis(IRGA),and the diurnal variation characteristics of soil respiration rate in different s... Soil CO_2 emissions of terraces and slope farmland in loess hilly and gully regions were measured by using Infra Red Gas Analysis(IRGA),and the diurnal variation characteristics of soil respiration rate in different slope positions of terraces and slope farmland were analyzed.The results show that the diurnal variation curves of soil respiration rate of terraces and slope farmland in loess hilly and gully regions had a single peak.The soil respiration rate of terraces reached the peak during 13:00-15:00,while the soil respiration rate of slope farmland reached the peak from 11:00 to13:00,and it was the lowest at next 07:00.The daily average of soil respiration rate in slope farmland was 0.86μmol/(m^2·s),accounting for 93.48% of that of terraces.The daily average of soil respiration rate in different slope positions of terraces and slope farmland is shown as follows:the bottom of the slope>the middle of the slope>the top of the slope.At the top of the slope,the daily averages of soil respiration rate in terraces and slope farmland were the same;at the middle and bottom of the slope,the daily average of soil respiration rate in terraces was larger than that of slope farmland. 展开更多
关键词 Soil respiration rate DIURNAL variation CHARACTERISTICS TERRACE Slope farmland loess hilly and gully regions China
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Dynamic Land Use /Cover Change and Analysis of Landscape Pattern in the Hilly and Gully Region of Loess Plateau: A Case Study of Pengyang County in Southern Ningxia
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作者 Jia HANG Yun SHI +1 位作者 Dahan HE Sha GENG 《Asian Agricultural Research》 2014年第7期38-43,48,共7页
The quantitative evaluation on land use /cover change as well as its influence on landscape pattern under the background of returning grain plots to forestry is significant to the sustainable utilization of land resou... The quantitative evaluation on land use /cover change as well as its influence on landscape pattern under the background of returning grain plots to forestry is significant to the sustainable utilization of land resources and ecological environment reconstruction in the southern Ningxia.Based on multi-temporal remote sensing data from four periods of Landsat TM /ETM,and combination of ecological quantity analytical method with GIS,the change of land use /cover and landscape pattern in Pengyang County of Ningxia Province were analyzed.The conclusions showed that the amount of each land use type was changed with different degrees,the area of forest /grass land increased,while farmland and unused land decreased.The change of landscape pattern was characterized as that the degree of landscape fragmentation,mixed distribution of patches,diversity index and evenness index increased gradually and then decreased,the connectivity between patches decreased gradually and then increased,and landscape shape presented irregular. 展开更多
关键词 Land use /cover change(LUCC) GIS LANDSCAPE pattern
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Quantitative analysis of the dynamic change and spatial differences of the ecological security: a case study of Loess Plateau in northern Shaanxi Province 被引量:5
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作者 LI Jing REN Zhiyuan ZHOU Zixiang 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期251-256,共6页
Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecologica... Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecological carrying capacity and ecological surplus/loss in 1986-2002 on the Loess Plateau in northern Shaanxi Province. What is more, this paper has put forward the concept of ecological pressure index, set up ecological pressure index models, and ecological security grading systems, and the prediction models of different ecological footprints, ecological carrying capacity, ecological surplus and ecological safety change, and also has assessed the ecological footprint demands of 10,000 yuan GDE The results of this study are as follows: (1) the ecological carrying capacity in northern Shaanxi shows a decreasing trend, the difference of reducing range is the fastest; (2) the ecological footprint appears an increasing trend; (3) ecological pressure index rose to 0.91 from 0.44 during 1986-2002 on the Loess Plateau of northern Shaanxi with an increase of 47%; and (4) the ecological security in the study area is in a critical state, and the ecological oressure index has been increasing rapidlv. 展开更多
关键词 regional ecological security dynamic change spatial difference quantitative analysis the loess Plateau in northern shaanxi Province
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A comparison between different ecological de-farming modes in the loess hilly-gully region in China 被引量:3
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作者 XUYong GUOTengyun YANGGuoan 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期53-60,共8页
The eco-environmental restoration has been a chief task of the western development strategies carried out by the central and local governments of China since the late 1990s, and the ecological de-farming has been rega... The eco-environmental restoration has been a chief task of the western development strategies carried out by the central and local governments of China since the late 1990s, and the ecological de-farming has been regarded as a powerful measure for the ecological restoration in the Loess Plateau and the upper reaches of the Yangtze River. "Relieving and de-farming" (RD) and "rebuilding terrace and de-farming" (RTD) are two more mature ones among various de-farming modes. Taking the loess hilly-gully region as a case, this paper summarized the basic characteristics of RD and RTD modes, calculated the sizes of de-farming slope farmland, rebuilt terraces, enlarged garden plots and restored vegetation, and compared the differences of two modes in terms of de-farming area, ecological reestablishment index, investment demand amount and benefits. The results showed that RTD mode has many advantages, including suitable investment, sufficient grain supply and great benefits, and will be the best ecological reestablishment mode in the loess hilly-gully region, and RD mode which is being carried out in this region should be replaced by RTD mode as soon as possible. 展开更多
关键词 ecological de-farming mode COMPARISON the loess hilly-gully region
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Geodetection analysis of the driving forces and mechanisms of erosion in the hilly-gully region of northern Shaanxi Province 被引量:6
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作者 员学锋 韩霁昌 +2 位作者 邵雅静 李玉恒 王永生 《Journal of Geographical Sciences》 SCIE CSCD 2019年第5期779-790,共12页
This paper analyzes the spatial variation in soil erosion in the loess hilly-gully region of northern Shaanxi Province, China. It sums up existing research, describes the factors that drive soil erosion, and uses geod... This paper analyzes the spatial variation in soil erosion in the loess hilly-gully region of northern Shaanxi Province, China. It sums up existing research, describes the factors that drive soil erosion, and uses geodetection to investigate the factors individually and in pairs.Our results show that soil erosion in the loess hilly-gully region of northern Shaanxi is mainly hydraulic erosion. There are significant spatial differences in the severity of soil erosion in the region. Generally, it is more severe in the north and west and less severe in the south and east. Individual factor detection results show that the major risk factors affecting soil erosion are human population distribution, precipitation, land-use type, elevation, and soil type. Interactive detection results show that interacting factors play much bigger roles in soil erosion than do individual factors. Based on forced detection results from different periods of time, we can see that forest and grass coverage, urbanization, and economic development in the study area all clearly inhibit soil erosion. 展开更多
关键词 soil EROSION driving factors geodetection loess hilly-gully region northern shaanxi
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Quantifying the vertical distribution pattern of land-use conversion in the loess hilly region of northern Shaanxi Province 1995–2015 被引量:4
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作者 曹智 李裕瑞 +1 位作者 刘正佳 杨凌帆 《Journal of Geographical Sciences》 SCIE CSCD 2019年第5期730-748,共19页
The mountainous and hilly region plays an important role in ecological safety and production in China. However, recent studies have poorly characterized the parallel structure of land use in the valleys of the mountai... The mountainous and hilly region plays an important role in ecological safety and production in China. However, recent studies have poorly characterized the parallel structure of land use in the valleys of the mountainous and hilly region using topographic factors(e.g.elevation, slope, aspect). Here, the loess hilly region of northern Shaanxi Province is used as a representative case area to analyze the vertical distribution pattern of land-use conversion using the relative elevation concept and the HAND index. The differences in the vertical structure of land-use conversion between absolute elevation and relative elevation were compared. We found that the classifications of absolute and relative elevation had similar proportions of each relative elevation grade in each absolute elevation grade. Cropland,woodland, and grassland were distributed evenly in each grade of absolute/relative elevation,while water body, built-up land and unused land were more likely to spread in low grades of relative elevation than those of absolute elevation. The land-use conversion(i.e. loss of cropland and gain in woodland and built-up land) showed an apparently stepped distribution with relative elevation classification, suitable for revealing vertical distributions of land-use conversion in the loess hilly region. Cropland transformed to woodland was mainly distributed in high grade of relative elevation, decreasing with a decrease in grades, while built-up land transformed from cropland and grassland was mainly distributed in low grade of relative elevation, decreasing with increases in grades. The grade of relative elevation where cropland transformed to woodland descended with the implementation of the Grain for Green Project. Our results suggest that it is better to analyze the vertical distribution of land-use conversion with relative elevation classification in hilly regions. 展开更多
关键词 land use change VERTICAL distribution pattern topographic factors HAND(Height above the Nearest Drainage) loess hilly region northern shaanxi PROVINCE
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罗玉沟流域水沙变化趋势及影响因素 被引量:1
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作者 秦瑞杰 李平 +2 位作者 肖培青 马田铂 王柯凡 《水土保持研究》 CSCD 北大核心 2024年第1期151-158,共8页
[目的]探讨小流域水沙变化趋势及影响因素,为黄土高原丘陵沟壑区水土流失治理和水土保持措施布设提供参考依据。[方法]采取Spearman秩次相关检验方法、累积距平法和双累积曲线法等对黄土丘陵沟壑区罗玉沟流域1986—2016年降水量、径流... [目的]探讨小流域水沙变化趋势及影响因素,为黄土高原丘陵沟壑区水土流失治理和水土保持措施布设提供参考依据。[方法]采取Spearman秩次相关检验方法、累积距平法和双累积曲线法等对黄土丘陵沟壑区罗玉沟流域1986—2016年降水量、径流量和输沙量变化趋势和演变过程进行分析。[结果](1) 1986—2016年罗玉沟流域年降水量趋势性变化不显著;流域年径流量和年输沙量变化具有明显的阶段性,以1993年为界,年径流量和年输沙量呈显著降低趋势。(2)降水和水土保持措施影响罗玉沟流域年径流量和输沙量,不同降水水平年,降水和水土保持措施对流域水沙变化的影响不同,水土保持措施使流域枯水年份径流量和输沙量减少最为显著。(3)水土保持措施对年径流量和年输沙量的减少贡献率分别为83.50%和80.97%。[结论]降水量变化不显著的情况下,水土保持措施对罗玉沟流域年径流量和年输沙量的减少起主导作用,水土保持综合治理对枯水年径流量和输沙量的影响幅度最大。 展开更多
关键词 黄土丘陵沟壑区 罗玉沟流域 水沙变化 影响因素
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黄土高原河谷城镇“川—沟”融合单元发展路径研究
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作者 田达睿 卫雨欣 +1 位作者 白钰 席佳榕 《规划师》 北大核心 2024年第7期104-111,共8页
通过分析黄土高原河谷城镇独特的城乡关系与发展困境,认为川道与次沟空间结构一体化、功能结构差异化发展是振兴黄土高原丘陵沟壑区的重要突破口,由此提出“川—沟”融合单元的概念内涵与划定方法。以榆林市绥德县为例,打破镇域行政边... 通过分析黄土高原河谷城镇独特的城乡关系与发展困境,认为川道与次沟空间结构一体化、功能结构差异化发展是振兴黄土高原丘陵沟壑区的重要突破口,由此提出“川—沟”融合单元的概念内涵与划定方法。以榆林市绥德县为例,打破镇域行政边界和小流域镇村体系,基于川道城镇和次沟乡镇的空间关联关系划定10个融合单元,并从用地形态结构、产业经济地理、服务设施配置等方面对融合单元的空间构型、功能类型和服务水平进行剖析,探讨川道与次沟协同视角下以融合单元为抓手推动黄土高原河谷城镇高效发展和管控治理的新路径。 展开更多
关键词 “川—沟”融合单元 城乡发展路径 黄土高原丘陵沟壑区 河谷城镇 榆林市绥德县
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黄土丘陵沟壑区村庄生态系统服务对人类福祉的影响机理——以陕西省米脂县为例 被引量:1
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作者 刘迪 陈海 +2 位作者 王麒菲 张杰 石金鑫 《水土保持研究》 CSCD 北大核心 2024年第3期69-78,共10页
[目的]在生态脆弱区,探究村庄生态系统服务对人类福祉的影响机理,为推动区域可持续发展提供参考。[方法]以黄土丘陵沟壑区陕西省米脂县为例,基于生物物理指标、人类需求理论分别评估村庄服务与福祉,分析了两者的空间分布。基于结构方程... [目的]在生态脆弱区,探究村庄生态系统服务对人类福祉的影响机理,为推动区域可持续发展提供参考。[方法]以黄土丘陵沟壑区陕西省米脂县为例,基于生物物理指标、人类需求理论分别评估村庄服务与福祉,分析了两者的空间分布。基于结构方程模型揭示了村庄禀赋视角下村庄服务对福祉的影响机理。[结果](1)作物和肉类空间分布相近,水果供给呈集中分布;高土壤保持村庄分布于南部丘陵,水源涵养和生境质量均西部高于东部;景观美学东部高于西部,高休闲娱乐村庄集中于城镇区。(2)村庄各需求、福祉空间分布差异较大。高福祉村庄包括川道村、多数乡镇中心村、乡村振兴示范村;低福祉村庄主要位于东西部丘陵,需政府重点关注。(3)村庄服务对福祉产生正向影响,作物、肉类、水源涵养是影响村庄福祉的关键服务。村庄禀赋对服务、福祉产生正向影响,且村庄禀赋通过提高村庄ES间接改善村庄福祉水平。高程是关键的自然禀赋,非文盲率和老龄化率是关键的社会禀赋;距县城距离是关键的区位禀赋。[结论]村庄服务与福祉空间差异明显,禀赋—服务—福祉的影响路径显著。依据空间差异与路径差异施策,是提升生态系统服务福祉贡献的要求。 展开更多
关键词 生态系统服务 人类福祉 空间分异 影响机理 黄土丘陵沟壑区 陕西省米脂县
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北洛河上游流域植被覆盖度时空变化及其地形分异特征 被引量:1
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作者 陈浩 权倍平 +3 位作者 李占斌 郭晋伟 李伟涛 张晓萍 《水土保持研究》 CSCD 北大核心 2024年第2期219-227,239,共10页
[目的]揭示退耕还林还草工程实施前后黄土丘陵沟壑区流域植被恢复过程,阐明流域植被恢复的地形分异效应,进而为黄土丘陵沟壑区制定适宜的流域生态建设和保护对策提供科技支撑。[方法]基于北洛河上游流域1990—2019年4期Landsat影像及数... [目的]揭示退耕还林还草工程实施前后黄土丘陵沟壑区流域植被恢复过程,阐明流域植被恢复的地形分异效应,进而为黄土丘陵沟壑区制定适宜的流域生态建设和保护对策提供科技支撑。[方法]基于北洛河上游流域1990—2019年4期Landsat影像及数字高程模型数据,利用像元二分模型结合GIS技术,开展了退耕还林还草工程实施前后该流域植被覆盖度变化地形分异特征研究。[结果](1)流域植被覆盖度在空间上呈现东南高、西北低的分异特征。1990—2019年流域年均植被覆盖度呈持续上升趋势,在退耕还林还草工程实施以后高等级植被覆盖度面积占比大幅提升,1990年、2000年、2010年、2019年高等级植被覆盖度面积占比分别为0.97%,6.96%,42.17%,64.18%。(2)在工程实施的各个时期,流域植被覆盖总体持续改善,但西北局部地区植被退化。研究期间,流域植被覆盖度结构改善明显,中高及高植被覆盖度面积以转入为主,中低及低植被覆盖度面积以转出为主。(3)流域植被覆盖度在地形上存在明显分异特征,植被覆盖度随高程的增加呈减小趋势,植被覆盖度与坡度呈正相关,坡度越陡,植被覆盖度越大,植被覆盖度随坡向遵循阴坡>半阴坡>平地>半阳坡>阳坡的分布规律。[结论]实施退耕还林还草工程对增加北洛河上游流域植被覆盖度起到了关键作用,但部分区域植被退化严重,未来该流域应重点关注城市空间扩展以及气候变化对植被建设的影响,以应对环境演变下植被生态系统可持续发展面临的挑战。 展开更多
关键词 植被覆盖度 时空变化 地形因子 退耕还林还草工程 黄土丘陵沟壑区
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多源土地利用产品在黄土丘陵沟壑区的精度评估
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作者 陈乐 卫伟 《水土保持学报》 CSCD 北大核心 2024年第3期177-186,194,共11页
[目的]为评估多源土地利用产品在黄土丘陵沟壑区的精度。[方法]以黄河二级支流关川河流域为例,基于高精度GCLUCC土地利用数据,从空间分布、面积特征、样本点精度和空间一致性4个方面评估空间分辨率为10,30 m的6种土地利用产品(WorldCove... [目的]为评估多源土地利用产品在黄土丘陵沟壑区的精度。[方法]以黄河二级支流关川河流域为例,基于高精度GCLUCC土地利用数据,从空间分布、面积特征、样本点精度和空间一致性4个方面评估空间分辨率为10,30 m的6种土地利用产品(WorldCover 10 m、ESRI 10 m、GLC_FCS30-2020、GlobleLand30、CNLUCC和CLCD)的准确性。GCLUCC数据是基于GF-2(0.8 m)、DEM(5 m)、野外采样点(6400个)和Google Earth样本点(2320个),采用面向对象法和人工目视解译,空间分辨率为1 m,整体精度超过95%。[结果](1)分类特征方面,多数产品能提取主要土地类别,但提取效率和准确度存在明显差异,特别是在耕地、林地和建设用地等地类的空间分布上。(2)面积一致性上,各产品与GCLUCC在不同地类的面积上存在显著差异。部分产品的草地面积是GCLUCC的2倍以上,而林地和水域面积仅占GCLUCC的0.13%~12.11%和1.41%~11.27%。(3)整体精度方面,GlobleLand30和WorldCover 10 m展现较高精度,空间图谱精度分别达到58.21%和50.19%。而CLCD和CNLUCC的准确性相对较低,其中,林地与草地、耕地与草地及建设用地与耕地间的分类混淆严重。(4)所有产品与实际地表间的空间误差显著,尤其在对乔木、灌木、裸地和水体分类上面临挑战。[结论]当前土地利用产品在黄土丘陵沟壑区精确表征地表覆盖特征方面存在挑战。未来的产品开发应更多地考虑地形和地理特征,并加强对特定土地利用类型的识别。研究结果可为黄土高原生态保护和地表信息获取提供理论参考。 展开更多
关键词 黄土丘陵沟壑区 土地利用/覆被产品 精度评估 面向对象分类
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人类活动对延河流域生态地质环境承载力影响研究
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作者 钟佳悦 郝利娜 +1 位作者 张明颖 严丽华 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第5期87-95,共9页
目的为探究治沟造地和平山造城重大工程对延河流域生态地质环境承载力(ecogeological environment carrying capacity,EGCC)的影响,方法利用分形理论和信息量模型构建研究区EGCC评价模型,揭示延河流域环境承载力时空模式及流转态势,构... 目的为探究治沟造地和平山造城重大工程对延河流域生态地质环境承载力(ecogeological environment carrying capacity,EGCC)的影响,方法利用分形理论和信息量模型构建研究区EGCC评价模型,揭示延河流域环境承载力时空模式及流转态势,构建人类活动强度指数,采用最小二乘法和皮尔逊相关系数探讨人类活动与EGCC之间的关系。结果结果表明:延河流域1990—2018年EGCC整体状况明显改善,平均值从−0.299上升至−0.197;EGCC分布多年来呈“中部最高,东南次之,西北最低”格局;人类活动强度从1990年成片分布逐渐发展到2018年“单核辐射”分布,高强度区主要分布在延河流域中部;人类活动强度与EGCC相关度较高,一定范围内呈正向促进关系;受平山造城工程活动影响,2010—2018年高水平和较高水平承载力面积分别增加了1.610,3.164 km2;EGCC变化趋势因治沟造地工程所处乡、镇地理位置和发展侧重不同而存在差异。结论人类活动与生态地质环境承载力呈较强的正相关关系,治沟造地和平山造城工程对EGCC具有一定积极影响。 展开更多
关键词 黄土丘陵沟壑区 治沟造地 平山造城 生态地质环境 承载力
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陕北黄土高原沟壑区文物遗产时空分布规律研究
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作者 段涵 林予欣 颜培 《建筑与文化》 2024年第7期209-211,共3页
揭示陕北黄土高原沟壑区文物遗产的分布特征,为该地区历史文化时空变迁研究与历史文化空间格局的凝炼提供借鉴。研究将文物遗产按照其所承载的内涵分为聚居型、人文型、防御型与近现代文物遗产四类,运用地理信息技术分析其空间分布特征... 揭示陕北黄土高原沟壑区文物遗产的分布特征,为该地区历史文化时空变迁研究与历史文化空间格局的凝炼提供借鉴。研究将文物遗产按照其所承载的内涵分为聚居型、人文型、防御型与近现代文物遗产四类,运用地理信息技术分析其空间分布特征,结合历史、文化、社会等时空变迁脉络研究陕北黄土高原沟壑区文物遗产的时空分布规律及其影响因素,指出河流道路的位置与走向对聚居型文物遗产的分布具有较大影响,自然山川的形势决定了人文型文物遗产的选址与布局,政治军事活动推动了防御型遗产“由点至带”的发展演变。 展开更多
关键词 陕北黄土高原沟壑区 文物遗产 分布特征 时空规律
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黄土丘陵沟壑区降雨特征对不同土地利用类型坡面产流产沙的影响
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作者 石默杰 杨光 +3 位作者 薛艳春 吴际 思彩花 刘一 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2024年第10期101-109,118,共10页
【目的】探究黄土丘陵沟壑区降雨特征及其对不同土地利用类型坡面产流产沙的影响。【方法】2019-2021年,以内蒙古达拉特旗合同沟小流域为研究区,设置5个不同土地利用类型(裸地、天然草地、灌木林地、农地、乔木林地)径流小区,监测研究... 【目的】探究黄土丘陵沟壑区降雨特征及其对不同土地利用类型坡面产流产沙的影响。【方法】2019-2021年,以内蒙古达拉特旗合同沟小流域为研究区,设置5个不同土地利用类型(裸地、天然草地、灌木林地、农地、乔木林地)径流小区,监测研究区的降雨特征指标(降雨量、降雨历时、30 min最大降雨强度(I 30)、平均降雨强度、降雨侵蚀力),利用K-均值聚类法,以研究区的降雨特征指标为变量,对合同沟小流域的侵蚀性降雨进行分类;计算不同土地利用类型径流小区的径流深和土壤流失量,分析不同土地利用类型和不同降雨类型对坡面产流产沙的影响,最后分析了合同沟小流域降雨特征与不同土地利用类型坡面总径流深和总土壤流失量的相关性。【结果】(1)2019-2021年,合同沟小流域降雨分布不均匀,共发生降雨128次,其中侵蚀性降雨51次,侵蚀性降雨量占总降雨量的80.2%,且侵蚀性降雨主要集中在6-8月。(2)将侵蚀性降雨分为3类:Ⅰ类降雨(大雨量、长历时、高强度);Ⅱ类降雨(中雨量、中历时、中强度)和Ⅲ类降雨(小雨量、短历时、低强度)。与Ⅱ类降雨和Ⅲ类降雨相比,Ⅰ类降雨发生的频次较低,但其平均降雨侵蚀力较强;在同一土地利用类型下,Ⅰ类降雨造成的坡面径流深和土壤流失量均明显较大。(3)2019-2021年,不同土地利用类型径流小区坡面产流产沙特征差异明显,总径流深和总土壤流失量由大到小依次为裸地>农地>天然草地>灌木林地>乔木林地。(4)各降雨特征指标与不同土地利用类型的坡面总径流深和总土壤流失量均呈正相关关系,其中降雨量、降雨强度和I_(30)的影响较大。【结论】在黄土丘陵沟壑区,降雨量、降雨强度和I_(30)是影响坡面产流产沙的最主要指标,天然草地、乔木林地、灌木林地的减流减沙效益较好,可知农地退耕还林还草工程是减少土壤侵蚀的有效措施之一。 展开更多
关键词 黄土丘陵沟壑区 土地利用 坡面产流产沙 水土保持
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An applied research on remote sensing classification in the Loess Plateau 被引量:5
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作者 LIU Yongmei TANG Guoan +1 位作者 LI Tianwen YANG Qinke 《Journal of Geographical Sciences》 SCIE CSCD 2003年第4期395-399,共5页
Dae to complex terrain of the Loess Plateau, the classification accuracy is unsatisfactory when a single supervised classification is used in die remote sensing investigation of the sloping field. Taking the loess hil... Dae to complex terrain of the Loess Plateau, the classification accuracy is unsatisfactory when a single supervised classification is used in die remote sensing investigation of the sloping field. Taking the loess hill and gully area of northern Shaanxi Province as a test area, a research was conducted to extract sloping field and other land use categories by applying an integrated classification. Based on an integration of supervised classification aad unsupervised classification, sampling method is remarkably unproved. The results show that the classification accuracy is satisfactory by the method and is of critical significance in obtaining up-to-date information of the sloping field, which should be helpful in the state key project of converting farmland to forest and grassland on slope land in this area. This research sought to improve the application accuracy of image classification in complex terrain areas. 展开更多
关键词 remote sensing integrated classification loess hilly and gully area sloping field shaanxi
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陕北黄土沟壑区采煤沉陷对黄土坡面形态的影响及土壤侵蚀效应 被引量:5
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作者 宋世杰 孙涛 +3 位作者 郑贝贝 牛瑞琳 阮豪 成星 《煤炭科学技术》 CAS CSCD 北大核心 2023年第2期422-435,共14页
如何破解煤炭开采与水土保持之间的矛盾是实现黄河中游生态环境保护与高质量发展的关键科学问题。以陕北黄土沟壑采煤沉陷区为研究对象,针对主采煤层典型地质赋存特征,以地下采厚(9、7、5 m)、地表黄土自然坡面坡形(直线坡、凹形坡、凸... 如何破解煤炭开采与水土保持之间的矛盾是实现黄河中游生态环境保护与高质量发展的关键科学问题。以陕北黄土沟壑采煤沉陷区为研究对象,针对主采煤层典型地质赋存特征,以地下采厚(9、7、5 m)、地表黄土自然坡面坡形(直线坡、凹形坡、凸形坡、复合坡)及坡度(5°、15°、25°、35°、45°)为变量,共构建了60个数值模型,基于FLAC3D数值模拟软件,研究了黄土自然坡面形态及采厚耦合作用下坡面形态演变过程与规律,基于中国水土流失方程(CSLE模型)和经验模型,计算与分析了沉陷坡面土壤侵蚀效应。研究结果表明:(1)采煤沉陷会导致地表黄土坡面的坡度增大,且采厚越大,坡度增幅越大,大采厚对采煤沉陷导致地表黄土坡面坡度的增大会产生明显的放大效应。凹形坡普遍对沉陷坡面坡度的影响显著,特别是在“采厚5 m、自然坡度>5°”“采厚7 m、任意自然坡度”“采厚9 m、自然坡度≤35°”条件下。无论在何种采厚及自然坡形情况下,≤5°的自然坡度对沉陷坡面坡度增幅的影响均最大。(2)采煤沉陷会导致“年侵蚀降雨”尺度下地表黄土坡面的土壤侵蚀模数M_(1)增大,且采厚越大,M1增幅越大;当采厚从5 m增大到9 m时,M_(1)增幅增大了1倍左右;4种坡形中凹形坡对沉陷坡面M1的增幅影响最大;≤15°自然坡度对沉陷坡面的M1增幅影响较大,在“采厚9 m,凹形坡”条件下超过了20%。(3)采煤沉陷会导致“典型场次侵蚀降雨”尺度下地表黄土坡面的土壤侵蚀模数M_(2)增大,且采厚越大,M_(2)增幅越大;当采厚从5 m增大到9 m时,M2增幅增大了1倍左右;4种坡形中凹形坡对沉陷坡面M2的增幅影响最大;≤15°自然坡度对沉陷坡面的M2增幅影响较大,在“采厚9 m,凹形坡”条件下超过了17%。该结果可为陕北矿区乃至黄河流域中游的水土流失精准防控与高质量发展提供科学依据。 展开更多
关键词 陕北黄土沟壑区 采煤沉陷 地表形态 土壤侵蚀 坡形 坡度
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Eco-environment Restoration and Regional Differentiation Characteristics Based on “Building Terrace and Returning Slope Farmland to Forests and Grass”
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作者 Yanhua LIU Yong XU 《Asian Agricultural Research》 2013年第1期41-47,共7页
Based on the scientific and technological achievements in the past decade in the Loess Hilly-gully Region and the successful demonstration experience in Yan'an Yangou watershed, we summarize the characteristics of... Based on the scientific and technological achievements in the past decade in the Loess Hilly-gully Region and the successful demonstration experience in Yan'an Yangou watershed, we summarize the characteristics of eco-environment restoration pattern based on "building terrace and returning slope farmland to forests and grass". According to the data on land use, slope farmland and the agricultural population in 1999, we calculate the area of new terrace that needs to be built, the area of garden plot that needs to be extended, vegetation restoration area and investment demand in counties (cities, districts). Establishing and using some indicators, such as basic farmland extension indicator, garden plot extension indicator, vegetation restoration index and investment demand density, we conduct type classification and analysis of regional differentiation characteristics in 55 counties (cities, districts). The results show that in the Loess Hilly-gully Region, 691 600 hm2 of new terrace needs to be built, 792 000 hm2 of economic forests and orchards need to be extended, 5 410 200 hm2 of vegetation needs to be restored, and the total investment demand is 15.82 billion yuan; in terms of geographical distribution, obviously there are two key areas for eco-environment restoration (one is located in the border area between northern Shaanxi and northwestern Shanxi, and the other is located in the eastern Gansu and southern Ningxia area); the classified regional guidance policies should be formulated as soon as possible, and the limited funds should be concentrated in the key areas. 展开更多
关键词 ECO-ENVIRONMENT restoration "Building TERRACE and
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人地关系视角下黄土丘陵沟壑区乡村公服设施布局优化探析——以陕西子洲县为例
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作者 段德罡 李凯欣 《小城镇建设》 2023年第2期73-82,共10页
城镇化水平的不断提高,使得乡村社会的发展认知由“底线思维”向“发展思维”转变,村民需求由“生存型”向“品质型”转变。加之近年来国家关于公共服务均等化政策的落实与深化,乡村公服设施建设的“量与质”都有了较大提升,但由于忽视... 城镇化水平的不断提高,使得乡村社会的发展认知由“底线思维”向“发展思维”转变,村民需求由“生存型”向“品质型”转变。加之近年来国家关于公共服务均等化政策的落实与深化,乡村公服设施建设的“量与质”都有了较大提升,但由于忽视了村庄的地域特征、人口发展、村民需求等因素,使得现有乡村公服设施配置出现使用效率低下、空间品质不佳、功能关联性较差等问题。基于此,本文通过陕西省榆林市子洲县乡村公服设施空间布局分析,采用田野调查、POI数据分析等方法进行深入研究,总结子洲县公服设施问题主要体现在需求供给错配、空间布局错位,功能行使错用三方面。最后基于人地关系视角,探寻人口流动与地理空间对公服设施配置的影响,并提出黄土高原丘陵沟壑区乡村公服设施优化布局策略,以期为提高我国乡村地区的发展能力,推进城乡一体化建设,早日实现乡村振兴提供参考。 展开更多
关键词 公共服务设施 黄土高原丘陵沟壑区 人口流动 地域差异 陕西省子洲县
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宁南黄土丘陵区侵蚀沟不同部位植物多样性与土壤养分 被引量:5
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作者 王亚娟 陈云明 +1 位作者 孙亚荣 赵敏 《水土保持研究》 CSCD 北大核心 2023年第5期99-105,共7页
[目的]探明宁南黄土丘陵区侵蚀沟不同部位植物多样性与土壤养分的关系,为侵蚀沟的水土保持及防护提供依据。[方法]以宁夏彭阳县玉洼流域3个稳定侵蚀沟的沟头、沟床、沟岸为对象,通过野外植被调查,同时采集0—10,10—25,25—40,40—55,55... [目的]探明宁南黄土丘陵区侵蚀沟不同部位植物多样性与土壤养分的关系,为侵蚀沟的水土保持及防护提供依据。[方法]以宁夏彭阳县玉洼流域3个稳定侵蚀沟的沟头、沟床、沟岸为对象,通过野外植被调查,同时采集0—10,10—25,25—40,40—55,55—70 cm土样,在室内测定土壤有机碳、土壤全氮、土壤全磷含量,分析了侵蚀沟不同部位(沟头、沟床、沟岸)的植物多样性及土壤养分特征。[结果]侵蚀沟沟头植物隶属3科6属,禾本科4属4种,伞形科和豆科各1属1种;沟床植物隶属5科12属,禾本科4属4种,菊科5属5种,豆科、茜草科和伞形科各1属1种;沟岸植物隶属3科7属,禾本科4属4种,豆科2属2种,伞形科1属1种。侵蚀沟各部位植物种数表现为:沟床>沟岸>沟头,均以禾本科植物为主。生活型上,各部位均以多年生草本植物搭配一、二年生草本植物为主。侵蚀沟的地上生物量、Shannon-Wiener指数、Patrick指数和Margalef指数均表现为:沟床>沟岸>沟头;Simpson指数表现为:沟头>沟床>沟岸;Pielou指数表现为:沟头>沟岸>沟床。侵蚀沟各部位平均土壤有机质、土壤全磷和土壤全氮含量均表现为:沟床>沟岸>沟头,且主要集中在0—10 cm和55—70 cm。侵蚀沟沟头和沟岸的地上生物量与土壤有机碳呈极显著正相关(p<0.01)、与土壤全磷呈显著正相关(p<0.05);侵蚀沟沟床的Shannon-Wiener指数与土壤全磷呈显著负相关(p<0.05),地上生物量与土壤有机碳呈极显著正相关(p<0.01)。[结论]侵蚀沟沟头易崩塌且土壤养分条件较差,应配置根系发达、茎干粗壮、耐冲性强的乡土树种,沟床、沟岸养分较高可优先配置碳、氮、磷含量需求较大的草本或灌木。 展开更多
关键词 宁南黄土丘陵区 侵蚀沟 沟头 沟床 沟岸 物种多样性 土壤养分
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