• 2000—2020年黄河流域土地生态质量及其变化趋势预测

    Subjects: Geosciences >> Geography submitted time 2023-11-13 Cooperative journals: 《干旱区地理》

    Abstract:黄河流域生态保护对我国高质量发展具有重要战略意义。从生态本底、生态结构、生态效益、生态胁迫4方面构建土地生态质量评价指标体系,基于理想点法对2000、2005、2010、2015、2020年黄河流域土地生态质量进行评价,结合Slope趋势预测及F显著性检验模型对2025年黄河流域土地生态质量变化趋势进行预测,并对预测结果进行冷热点分析,以探究2025年流域土地生态质量发展趋势集聚区。结果表明:(1) 20002020年黄河流域土地生态质量呈东南部、西南部整体高于东北部、西北部的分布特征。(2) 20002020年黄河流域土地生态质量整体较低,但呈自东南部向西北部逐渐好转的态势。(3) 2000年黄河流域土地生态本底质量较差的中上游区域质量上升空间大,好转现象明显。(4) 2025年黄河流域土地生态质量呈上升趋势的区域主要集聚在流域甘肃段东部和中部、宁夏段南部,位于黄土高原生态功能保护区;土地生态质量可能会下降的区域,部分集聚于流域青海段西南部的黄河源生态功能保护区,部分集聚于流域内蒙古段西北部。黄河流域西北部要持续推进生态治理,为区域高质量发展奠定生态基础,流域东南部在加强生态保护和监测的同时继续推进经济发展,实现经济与生态互相促进的良性发展。

  • Identification of rural residential development types in loess hilly and gully region: A case of Wuqi County

    Subjects: Geosciences >> Geography submitted time 2023-04-07 Cooperative journals: 《干旱区地理》

    Abstract: This study uses a minimal cumulative resistance model to explore the suitability of a residential area layout from the perspective of ecology and construction and studies network relations of residential areas through social network analysis. Starting from the significance of the overall residential area suitability and individuals, this study also identifies various types of residential development in Wuqi County, Yan’an City, Shaanxi Province, China. The following results are presented. (1) The rural residential areas in Wuqi County have zonal distribution, and a clustering feature is observed in a scattered distribution. The terrain and traffic conditions are the key constraints to determining the residential area distribution in the loess hilly and gully regions. Additionally, the overall clustering degree is low, and the average scale is 1500 m2 . (2) Suitability zoning is conducted using the minimal cumulative resistance model to consider the suitability of land use in rural residential areas under the constraints of an ecological environment. In accordance with zoning results, the suitable construction area, buffer zone, and ecological protection area show the characteristics of“overall agglomeration and partial dispersion”. A total of 62.83% of rural residential areas are situated in the suitable construction area and the overall layout is reasonable, but the layout of some residential areas has exerted impacts on the regional ecological stability. (3) Considering the results of network analysis, one central node is found at least in a village and town. However, the existing residential area network structure of some towns is not uniform and the existing network structure cannot boost the development of surrounding nodes. Therefore, village nodes with large development potential should be cultivated to promote the balanced development of villages and towns. (4) On the basis of the results of suitability zoning and network analysis, the zoning can be divided into the following four types:“direct town type”,“prior development type”,“conditional development type”, and“restricted expansion type”, and the corresponding development focuses are introduced. The research results can provide a reference for rational planning and rural residential development in the loess hilly and gully regions.

  • 黄土高原气候和人类活动对植被NPP变化的影响

    Subjects: Geosciences >> Geography submitted time 2022-03-28 Cooperative journals: 《干旱区研究》

    Abstract:本研究基于CASA模型获得黄土高原20002018年植被NPP数据集,通过相关性、残差分析等方法,定量分析了气候变化和人类活动对植被NPP变化的影响。结果表明:(1)黄土高原20002018年植被NPP呈东南高、西北低分布格局,研究区约86.86%区域植被NPP呈增加趋势,主要为退耕还林还草的核心区;呈下降趋势的面积占13.14%,主要分布在西北部的干旱区。(2)气候变化和人类活动对植被NPP变化的贡献率分别为48.78%和51.22%,在空间上有明显的差异性,人口稀少、发展相对落后地区的植被变化主要受气候变化的影响;人口众多、经济发展较好地区植被变化以人类活动为主。(3)黄土高原作为干旱半干旱区植被对气候变化的响应较为敏感,随着人类活动的日益频繁,气候和人类活动共同作用于黄土高原的植被变化。本研究有助于理解气候变化和人类活动对植被动态变化的影响,并为黄土高原的植被恢复和高质量发展提供科学依据。

  • 基于格网GIS的黄河流域土地生态质量综合评价

    Subjects: Geosciences >> Geography submitted time 2022-02-11 Cooperative journals: 《干旱区地理》

    Abstract:以8 km8 km的格网为评价单元,从土地生态系统的景观特征、生境质量抗干扰能力、生态系统服务价值、社会经济效益4个角度构建土地生态质量评价体系,利用层次分析法和熵值法确定权重,通过空间自相关、冷热点分析和障碍度诊断模型,探究了黄河流域土地生态质量的空间分异规律。结果表明:(1)黄河流域土地生态质量空间上呈中部及西南部较高、东南和东北部中等、西 北质量较低的态势,土地生态质量总体较低,临界安全及危险区域分别占31.4%、27.7%。(2)黄河流域土地生态质量的空间自相关程度高,热点主要分布于治理强度较高的黄土高原、毛乌素沙地生态保护区,冷点分布于流域西北部,应适当加强上游区域土地生态的治理,消除极端冷点。(3)黄河流域土地生态质量主要障碍因子为经济密度、土地利用结构多样性、离生态保护区距离、离水域 距离,应立足区域自然基础和资源禀赋状况,加快绿色创新驱动,将丰富的自然资源、生物资源和历史文化资源转化为市场价值,在生态修复和改造时,合理配置人工生态系统结构,必要时可增设自然保护区。

  • 基于景观生态安全的神木市生态廊道识别与优化

    Subjects: Geosciences >> Geography submitted time 2021-08-12 Cooperative journals: 《干旱区研究》

    Abstract:以优化生态格局为出发点,对神木市景观生态安全进行评价。综合运用主成分分析法、自然断点法、MCR(Minimum Cumulative Resistance,MCR)模型,获取神木市生态安全格局的分布状况,并在此基础上提取生态源地,采用最小累积阻力模型构建生态廊道以优化生态景观格局。结果表明:神木市景观生态安全状况分为5级,1级区域多位于西北部,少部分分布在东南部及北部边缘地区,2级、3级区域在全域呈碎片化相间分布,4级、5级区域分别受人类活动和自然条件影响,在中部建设用地区成集中连片分布,东南部沟壑纵横区成碎片化分布;神木市生态廊道共121条,其中有19.08%的生态廊道独立存在,43.51%的生态廊道未与主要生态廊道群相连;设计新增生态廊道10条,总长76.69 km。通过新增生态廊道,完善生态廊道网络,加强独立生态廊道与生态源地的联系,对优化神木市景观生态环境,构建生态安全格局具有重要的参考意义。