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1.
黄河源区玛多县土地利用/覆被及景观格局变化的遥感分析 总被引：6，自引：3，他引：3
采用了黄河源地区1977、1990及2003年MSS、TM的3个时相遥感影像,通过人机交互的解译与GIS的空间分析,提取了玛多县3个时期的土地利用/覆被信息。分析了玛多县各地类的数量变化和空间变化特征。另外对景观生态空间分布格局,利用FRAGSTATS软件对玛多县景观级别的动态特征进行了分析。结果表明:玛多县的土地利用/覆被类型以草地为主,占全区总面积77.93%;退化现象十分严重,主要是草地覆盖度的降低以及草地沙化;景观破碎化程度在前期呈下降趋势,而后期呈上升趋势,景观斑块形态越来越偏离规则而变得复杂、多样。 相似文献
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准确认识三江源植被生产力月度尺度的时空格局变化,对三江源畜牧业生产以及生态保护政策制定具有重要意义,可稳定获取的重访周期为4 d的16 m分辨率GF-1/WFV数据使中等空间分辨率的月度NPP产品生产成为可能。本文建立了一套以GF-1/WFV为基本数据源的中等空间分辨率草地月度NPP估算技术方法,并评估了其在三江源地区应用的可行性。在黄河源区玛多县的实验表明以GF-1/WFV为基础,以MODIS13Q1数据为补充,可以获得覆盖全区的中等空间分辨率月度NDVI数据,据其反演得到的草地NPP,地面验证精度在70%以上,优于MODIS NPP产品精度,且能更为详细地反映草地生产力变化的空间差异,在青海三江源地区利用GF-1/WFV数据生产中等空间分辨率的草地月度NPP产品是可行的。 相似文献
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通过收集川西北高原地区近20年来的5个主要生态环境因子与牦牛、绵羊、山羊数量的数据资料,在建立二次多项式模型的基础上,进行了单因子边际分析.分析结论:牦牛和绵羊数量与生态环境因子间的多项式回归方程具有显著性,山羊数量与生态环境因子间的多项式回归方程不具有显著性.从而,提出了家畜生长的最适宜生态环境条件,为当地的畜牧业生产发展规划以及生态环境资源合理开发利用提供了科学的依据. 相似文献
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本文选择黄河三角洲大汶流自然保护区为研究对象,以多时相遥感影像,对土地利用类型进行解译分析。同时,以平均低潮线作为分析基线,提取海岸线变化信息。结果表明:1996-2009年研究区面积净增13.35km2。各种土地利用类型中滩涂所占面积最大,养殖池所占比例最小,但增幅明显。芦苇地面积后期增长迅速,指示研究区生态环境趋向转好。自然因素(黄河来水来沙量)和人类活动(黄河调水调沙工程,湿地恢复工程,滩涂规模开发以及人类开垦造田)是研究区土地利用类型变化的直接驱动力。1976-2009年研究区海岸净造陆面积217.14km2,沙嘴变幅为29.2km。黄河入海水沙量和滨海区的海洋潮流条件共同影响着海岸线的变迁。 相似文献
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西藏高原土地面积广阔,但适宜人类居住的空间却高度集中于局部地区,其中雅鲁藏布江中游地区是西藏高原最重要的人口承载区。利用核密度、空间“热点”探测和地理探测器等方法,从“居民点斑块-样带-研究区全域”构成的点-线-面多尺度揭示了雅鲁藏布江中游地区城乡居民点的规模、形态和密度的空间分异特征,并分析了自然因素对城乡居民点空间分异的影响。结果表明：① 全域尺度上,雅鲁藏布江中游地区各乡镇居民点规模空间差异较大,基本形成以“彭措林乡-增期乡”为轴线的南北对称态势,居民点形态普遍规则,密度总体偏低;② 样带尺度上,仅有拉萨河样带的密度分布呈线性分布,雅鲁藏布江样带和湘曲-年楚河样带的规模、形态和密度以及拉萨河样带的形态和规模在各自方向上均呈现非线性分布,即居民点东西方向呈现分布规模和形态“两端大中间小”、分布密度“两端小中间大”的特征,而南北方向规模、形态和密度均呈现“南大北小”的特征;③ 斑块尺度上,居民点规模普遍较小,面积小于1000 m 2的数量高达19 099个,占比达到55.14%;斑块形态比较规则,形状为规则类型的数量有21 256个,占比为61.37%;分布密度整体偏低,全域仅为0.34个/km 2;④ 自然要素中,海拔对居民点规模和密度的影响最大,地势起伏度和河流邻近性对居民点形态影响显著,而降水量对居民点的规模、形态和密度影响均不显著。 相似文献
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1菏泽市耕地现状 菏泽市位于山东省西南部，辖8县、1区和1个省级经济开发区，人口900万人，面积12239km^2，耕地面积83.13万hm^2，基本农田面积71.43万hm^2。黄河流经菏泽市4个县（区），全长185km，河面最宽10km，最窄3km，河水含沙量为27.8kg／m^3。根据最新国土、河务部门联合开展的淤涝地调查摸底统计， 相似文献
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三江源生态工程实施以来草地恢复态势及现状分析 总被引：1，自引：0，他引：1
三江源生态保护与建设工程实施以来,区域生态环境发生了明显的改善。为了正确认识该地区草地退化恢复的程度及其空间分布特征,本文通过对比分析2004年和2012年2期遥感影像,利用人工解译的手段获取了工程实施后三江源地区退化草地变化态势数据集,并在此基础上分析了退化草地的恢复态势,以及草地退化现状的空间格局特征。结果表明：① 2004-2012年三江源生态工程实施以后,该地区草地退化呈现不同程度的减缓态势,而且局部地区草地状况明显好转;② 三江源地区各县草地退化趋势基本得到控制,退化草地变化以轻微好转和明显好转为主,退化发生和退化加剧现象仅发生在极少数县;③ 2012年三江源退化草地面积比2004年降低了5.78%,其中中度退化草地的面积减少最显著,下降了5.35%。黄河源和长江源草地退化的形势依然比较严峻,玛多县、曲麻莱县、称多县北部和治多县东南部草地退化最明显。三江源生态工程自实施以来,草地恢复态势及现状分析对归纳总结三江源生态保护与建设一期工程的成功经验和基本教训,以及合理指导二期工程的实施具有重要的科学意义。 相似文献
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羊鼻山铁金钨成矿带是黑龙江省著名的铁金矿产开采矿山和整装勘查区之一。矿带走向北北西,北西由集贤县石门矿化区起,经双鸭山市羊鼻山铁钨矿至宝清县老柞山金矿止,全长62km,宽1km～3km。以找寻铁、金、钨矿产为主。 相似文献
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本文利用由遥感影像解译获得的土地利用数据和MODIS NDVI产品,采用空间转移矩阵、最大值合成法、均值法和一元线性回归模拟等方法,分析了2000年以来京津风沙源区生态环境变化的时空特征.结果表明:(1)2000-2005年京津风沙源区耕地开垦、林草地减少的趋势有所减缓,但区域气候变化趋于干旱,水域面积明显减少,草地退... 相似文献
11.
Factors influencing the grazing management styles of settled herders: a case study of Nagqu County, Tibetan Plateau, China 总被引：1，自引：1，他引：0
Xiao-bo Hua Jian-zhong Yan Xiang Liu Ying-ying Wu Lin-shan Liu Yi-li Zhang 《山地科学学报》2013,10(6):1074-1084
The implementation of pasture contracting policies in the Tibetan Plateau has been of widespread concern in the scientific community and related government departments. Studying the effects of the implementation of pasture contracting policies will help us understand herders＇ attitudes toward those policies and to amend existing policies effectively. This paper analyzes 135 herder families＇ grazing management behavior using participatory rural appraisal （PRA）, quantitative analysis and a Logistic regression model in three townships of Nagqu County in remote areas of the Tibetan Plateau, China. The results show that the herders have become settled and are no longer nomadic, so the settlement project has basically been completed and the policy of contracting for grazing rights is being gradually implemented in Nagqu County. Since the grazing rights and pastures were under contract, group-based management has been widely accepted in this area, which helps the herders deal with constraints, such as limited pasture area, a small grazing radius, controlled family animal husbandry and an uneven distribution of water. The herders that have more family members available for labor, higher proportion of family members with good health, and higher income from animal husbandry tend to choose household-based management. Herders tend to choose group-based management when higher quality winter pastures are available. 相似文献
12.
《山地科学学报》2019,(11)
Increasing populations of large carnivores are leading to tension and conflicts with livestock production, a situation that potentially might escalate.In Norway the objective of the large carnivore policy is two-folded: to ensure viable carnivore populations and to secure a sustainable grazing industry. The main instrument is zonation, with carnivore management zones(CMZs) prioritized for reproduction of the large carnivore species separated from other areas prioritized for grazing livestock. The objective of this paper is to describe current knowledge about the impact of the zoning management strategy on the grazing industry. This is done by documenting status and changes in sheep production, losses of livestock to predating carnivores,and the use of grazing areas inside and outside the CMZs. CMZs offering protection for lynx, wolverine,bear and wolf cover 55% of the Norwegian mainland.30% of the sheep and 50% of the Sami reindeer grazing areas are found inside the CMZs. Livestock(semi-domestic reindeer excluded) is using 59% of the available natural pasture areas outside the CMZs, but only 26% inside the CMZs. The lowest use of availablegrazing areas was found inside zones for wolves(12%)and brown bears(6%). Livestock in these zones are confined to fenced enclosures, mostly on the farm itself, or moved to pastures outside the management zone for summer grazing. Livestock losses increased in the affected regions during the period when carnivores were reestablished. Later, losses declined when CMZs were established and mitigation efforts were implemented in these zones. The bulk of sheep and reindeer killed by carnivores are now found in boundary areas within 50 km off the CMZs, where sheep are still grazing on open mountain and forest ranges. Therefore, instruments to protect livestock in areas close to the CMZs are also needed. The number of sheep declined inside the CMZs from 1999 to 2014,but increased outside the zones. The reduction in the absolute number of sheep in the CMZs is balanced by a similar increase outside, thus the total sheep production in Norway is maintained. We conclude that although of little consequence for the total food production in Norway, the economic and social impact of the large carnivore management strategy can be serious for local communities and individual farmers who are affected. There is a need for more exact carnivore population monitoring to quantify the carnivore pressure, better documentation of reindeer losses, and a clearer and stricter practicing of thezoning strategy. Increased involvement of social sciences is important in order to understand the human dimension of the carnivore conflicts. 相似文献
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面向中国洪涝灾害应急监测的无人机空港布局 总被引：1，自引：0，他引：1
当前洪涝灾害对社会的经济发展和人民生命财产安全构成严重威胁。无人机机动、灵活,安全性高,可迅捷甚至实时获取灾区影像,对灾情的快速评估和应急救援决策意义重大。遥感无人机在洪涝灾害救援中能够发挥的重要作用已得到广泛共识,但是由于灾害的突发性,缺乏就近部署的资源制约了无人机遥感观测和救援作用的发挥。针对突发灾害,在区域和全国范围内建立起一定的无人机遥感应急体系成为国家面向未来正在考虑的选项。基于此,本研究提出了基于中国科学院的野外台站构建全国无人机遥感观测网的设想。本研究以中国防范洪涝灾害等级分布数据、行政区划数据、中国科学院野外台站分布数据和当前无人机性能数据库为数据源;以行政区划离散并提取的中心点作为需求点,台站作为设施点,不同洪涝等级区域内需要无人机进行应急观测的重要程度作为权重,利用最大覆盖选址模型进行空港选址布局;利用成本-效益曲线确定台站的最佳数量,最终从268个台站中选取出81个作为支撑全国洪涝灾害无人机遥感观测网络的无人机空港。无人机空港布局结果在理论上能够实现对中国绝大数突发洪涝灾害在2 h内初步完成洪涝观测,这对于构建中国空天地一体化的洪涝灾害监测体系具有重要意义。同时,本研究中的方法和成果对于进一步构建行业和综合性的全国无人机遥感观测网也具有一定借鉴和参照意义。 相似文献
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Effects of grazing exclusion on soil carbon and nitrogen storage in semi-arid grassland in Inner Mongolia,China 总被引：1，自引：1，他引：0
Xing Wu Zongshan Li Bojie Fu Fei Lu Dongbo Wang Huifeng Liu Guohua Liu 《中国地理科学(英文版)》2014,24(4):479-487
The semi-arid grasslands in Inner Mongolia, China have been degraded by long-term grazing. A series of ecological restoration strategies have been implemented to improve grassland service. However, little is known about the effect of these ecological restoration practices on soil carbon and nitrogen storage. In this study, characteristics of vegetation and soil properties under continued grazing and exclusion of livestock for six years due to a nationwide conservation program—′Returning Grazing Lands to Grasslands(RGLG)′ were examined in semi-arid Hulun Buir grassland in Inner Mongolia, China. The results show that removal of grazing for six years resulted in a significant recovery in vegetation with higher above and below-ground biomass, but a lower soil bulk density and pH value. After six years of grazing exclusion, soil organic C and total N storage increased by 13.9% and 17.1%, respectively, which could be partly explained by decreased loss and increased input of C and N to soil. The effects of grazing exclusion on soil C and N concentration and storage primarily occurred in the upper soil depths. The results indicate that removal of grazing pressure within the RGLG program was an effective restoration approach to control grassland degradation in this region. However, more comprehensive studies are needed to evaluate the effectiveness of the RGLG program and to improve the management strategies for grassland restoration in this area. 相似文献
15.
Unmanned Aerial Vehicles(UAVs) have become popular and their use in agriculture monitoring is attracting more and more attention. There has emerged another class of agricultural UAVs whose normal consumer grade Red/Green/Blue(RBG) bands cameras have been modified to include the Near-Infrared(NIR) band by replacing one of the visible channel bands. This reduces the cost for agricultural UAVs. However, few researches have assessed the suitability of these modified UAV cameras in agricultural remote sensing. This study employed a modified UAV consumer grade camera with Blue/Green/Near Infra-red(BGNIR) bands to assess its applicability in crop remote sensing monitoring. Two experimental fields in Eastern Zimbabwe were used to assess the applicability of the modified BGNIR UAV camera in potato stress detection, maize senescence monitoring and chlorophyll concentration variations in bananas. Processed Green Normalized Vegetation Index(GNDVI) maps from the UAV imagery were compared with actual ground data of geo-tagged images taken during the UAV flights. Visual comparison between the ground and UAV imagery showed positive correlation. Highly stressed potato plants had lower GNDVI values than the healthier looking plants. Matured maize canopies also had lower GNDVI values than the late mature plants whose leaves were still green. GNDVI values in bananas from the first flight ranged from 0.094 91 to 0.334 74 and after the application of Nitrogen/Phosphorous/Potassium(NPK) fertilizer the GNDVI values ranged from 0.124 61 to 0.555 64. Increase in nitrogen also increases chlorophyll concentration in plant leaves hence the values of GNDVI increase after fertilization. We conclude that consumer grade modified UAV cameras are suitable in remote sensing of agricultural crops. Their adoption and utilization reduce the cost burden on farmers in developing countries especially in Africa, and help them to monitor their crops more efficiently. 相似文献
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近年来,针对中国生态环境、洪涝灾害应急响应、国土安全监测等遥感观测任务,无人航空遥感手段需求越来越多。构建异构无人航空器遥感观测多任务集群系统是近几年的发展目标,为完成无人航空遥感生态建设,垂直起降无人机以其不受场地限制起降又可快速巡飞的特点,在多个领域发挥着越来越大的作用。本文主要研究内容包括国内垂直起降无人机发展现状调研、面向航空遥感应用市场的无人机分析及典型机型介绍、垂直起降无人机在遥感领域的应用场景及案例分析、垂直起降无人机在遥感领域的应用前景及发展趋势等。通过广泛调研及深入分析可知,目前垂直起降固定翼无人机正逐步取代多旋翼飞行器的主导地位;垂直起降无人机占据了遥感应用无人机80.47%的市场份额;动力多元化、系统智能化、布局多样化、尺寸小型化等是面向遥感应用的垂直起降无人机的发展方向。本文较为全面地阐述和剖析了面向遥感应用的垂直起降无人机的相关内容,为遥感航空无人机生态建设提供了参考与支撑。 相似文献
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利用遥感对地观测技术对2020年夏季鄱阳湖地区发生的洪水灾情进行评估和分析,分别选取Landsat 8卫星4月和 Sentinel-1A雷达卫星7月的影像作为洪水发生前、后的影像,利用遥感专题信息提取、随机森林分类和变化检测技术揭示洪水淹没范围,以及被淹没的主要土地覆盖类型面积,同时结合水文气象和地形数据进行灾情和受灾原因分析。研究结果表明,鄱阳湖2020年洪灾的淹没面积为1961.95 km2,共造成区内110.83 km2建筑用地、760.54 km2耕地、71.59 km2林地、992.02 km2草地和26.97 km2裸地被淹,其中尤以鄱阳县受灾最为严重,其总受灾面积达到514 km2,其次为新建区与余干县,分别达到了330 km2和310 km2。持续2个月的强降雨使得鄱阳湖流域的水位超过了其1998年特大洪水的水位,加上长江水倒灌,湖区地势北高南低,积水不能及时排出,圩堤决口等诸多水文气象和地形因素造成了此次鄱阳湖的特大洪灾。 相似文献
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以牛羊为主的反刍动物养殖是我国甲烷的首要排放源,其中又以牛的排放占主导。我国的养殖牛中,黄牛的数量最为庞大,占总存栏牛的56%。在以往有关反刍动物甲烷排放的研究中,着重点多在于排放因子的测定及依据测定结果估算国家尺度的排放源清单。但是,对于反刍动物种群特征及环境因子变化造成的动物甲烷排放在空间和季节的差异却较少关注。本研究收集了我国不同地区46个亚科黄牛的个体特性数据及其生态因子,结合IPCC的反刍动物甲烷排放估算方法,分析了我国2005年黄牛甲烷排放因子的空间差异及其季节变化特征。结果表明,总体上农区肠道发酵排放因子,除4-6月因役用强度大的原因,而排放略高于牧区外,其他月份均小于牧区,而农区粪便管理排放因子全年高于牧区。肠道发酵排放因子在夏季小于其他季节,其月均排放因子为4.48 kg/head/m,粪便管理排放因子则表现出相反的季节格局,夏季粪便管理月均排放因子为0.44 kg/head/m。在7个大的分区中,肠道发酵年排放因子最大、最小区域分别为黄土高原区71.0 kg/head/a和西南区55.2 kg/head/a;粪便管理年排放因子最大、最小区域分别为东南区5.4 kg/head/a和青藏区0.1 kg/head/a。 相似文献
19.
基于改进蚁群算法的无人机低空公共航路构建方法 总被引：4，自引：0，他引：4
日益增加的无人机数量和飞手自由规划航线给航空安全带来极大隐患。构建一个安全、高效的航空飞行环境,可以为无人机活动设立隔离空域,并在隔离空域内规划无人机低空公共航路,以提高低空空域利用率,为无人机交通管理提供决策依据。本研究充分考虑无人机近地表飞行及其即时通讯等特点,以天津市为例,基于地理信息技术构建以多源地理空间数据为基础的无人机低空飞行环境,包括低空蜂窝网络环境、大气环境和政策空域环境等,并改进传统蚁群算法以搜索无人机最优路径,得到该区无人机低空公共航路网。研究结果表明,改进的蚁群算法大大提高了路径搜索效率,满足无人机航路规划的高时效性、动态更新等要求;并且天津市航路长度符合市场上现有的无人机最远航程要求,基本满足现有的无人机运输要求。本研究描述的无人机低空公共航路研究的核心算法和关键技术,可以为无人机管控系统提供核心技术支撑。 相似文献
20.
Vegetation traits and soil properties in response to utilization patterns of grassland in Hulun Buir City,Inner Mongolia,China 总被引：2，自引：1，他引：1
Numerous studies have focused on vegetation traits and soil properties in grassland, few of which concerned about effects of human utilization patterns on grassland yet. Thus, this study hypothesized that human disturbance （e.g., grazing, mowing and fencing） triggered significant variation of biomass partitioning and carbon reallocation. Besides, there existed some differences of species diversity and soil fertility. To address these hypotheses of grassland with diverse utilization patterns in Hulun Buir City, Inner Mongolia, China, we sampled in situ about aboveground biomass （AGB） and belowground biomass （BGB） to evaluate their biomass allocation. Species diversity and soil properties were also investigated. Subsequently, we discussed the relationship of species diversity with environmental conditions, using data collected from 23 sites during the ecological project period of Returning Grazing Lands to Grasslands （RGLG） program. The results were as follows： 1） both AGB and BGB were lower on grazing regime than those on fencing and mowing, but the ratio of root-to-shoot （R/S） was higher on grazing regime than the other two utilization patterns; 2） neither of evenness and Simpson Index was different significantly among all grassland utilization patterns in desert, typical, and meadow grassland at 0.05. In meadow grassland, species richness of fencing pattern was significantly higher than that of grazing pattern （p 〈 0.05）; 3） both of soil organic carbon content and soil available phosphorous content were increased significantly on fencing pattern than grazing pattern （p 〈 0.05） in desert grassland, and mowing patterns increased the soil nutrients （soil organic carbon, soil total phosphorous, soil available phosphorous, and soil total nitrogen） significantly compared with grazing patterns （p 〈 0.05） in typical grassland. However, there were no significant differences among utilization patterns in meadow grassland. In conclusion, both of AGB and BGB were increased s 相似文献