Subjects: Geosciences >> Cartography submitted time 2023-09-27 Cooperative journals: 《干旱区地理》
Abstract：中国山西-陕西-内蒙古交界地开采沉陷对地表土壤扰动强烈，引起地表生态损伤。为了揭示开采沉陷对土壤水盐运移的影响机制，通过建立土壤沉陷物理模型，利用沉陷剖面不同应力区土壤容重数据建立HYDRUS-2D水盐模型，研究土壤蒸发过程中，土壤水分、总盐分、不同溶质离子在不同沉陷应力区随土壤深度和运移时间的变化规律。结果表明：（1） 0~40 cm深度，沉陷拉张作用显著增强土壤蒸发作用，造成挤压区土壤含水率显著大于拉张区，土壤含水率随时间变化曲线呈现典型的蒸发过程三阶段模式。（2） 沉陷组各应力区土壤总含盐量不但随深度呈现强烈变异，具体表现为20~40 cm、60~80 cm土壤总含盐量相对积聚；而且右侧拉张区总含盐量积聚深度有向下迁移的趋势。（3） 沉陷拉张区Ca2+、SO42-、Mg2+、Cl-离子积聚浓度大于挤压区。Ca2+、SO42-、CO32-土壤离子浓度随深度呈单峰积聚，沉陷拉张区积聚深度均显著下移。（4） HYDRUS-2D水盐模型可以较好地模拟开采沉陷土壤剖面中的土壤水盐运移。土壤含盐量、含水率的实测值与模拟值率定结果为平均相对误差（ME）0.5，均方根误差（RMSE）0.5，决定系数（R2）>0.95，模拟精度满足试验要求。研究结果可为科学开展开采沉陷区生态修复工程、提高生态自修复能力提供重要理论依据。
Subjects: Geosciences >> Cartography submitted time 2023-07-19 Cooperative journals: 《干旱区地理》
Abstract：农牧交错区的土地利用转型及生态环境建设，是我国西北地区可持续发展的重要支撑。基于三生空间视角，运用包头市2000、2010、2020年3期遥感数据，通过土地转移矩阵、生态环境质量指数和生态贡献率等方法，分析其土地利用转型特征与生态环境效应。结果表明：（1）研究期内包头市三生空间总体格局稳定，生产、生态用地减少，生活用地持续增加。牧草生态用地转出面积最多，农业生产用地次之；城镇生活用地与工矿生产用地流入面积最大。（2）20002020年包头市生态环境质量指数下降，分别为0.6292、0.6208、0.6194，但改善趋势大于恶化趋势；城市北部生态高质量区面积有所减少；中部中质量区缓慢减少，南部低质量区持续向东南方向递增。（3）牧草生态用地被占用产生的生态环境负效应较大，而其他生态用地、农业生产用地向牧草生态用地转化则为生态环境改良的主导因素。通过研究包头市的土地利用转型及其生态环境效应，以期为农牧交错区城市的三生空间优化、生态环境保护提供借鉴。
Subjects: Geosciences >> Cartography submitted time 2023-03-13 Cooperative journals: 《干旱区研究》
Abstract： Carrying out the optimal allocation of land use is aimed at promoting the scientific use of regional land resources and achieving carbon emission reduction targets. In this paper, the Fenhe River Basin is taken as the research area. Based on the data on land use and resistance factors in 2015 and 2020, the FLUS-MCR model and the carbon budget coefficient method are used to verify the accuracy of the model. Five simulation scenarios, such as low- carbon development priority, economic development priority, cultivated land protection priority, ecological protection priority, and natural development in 2030, are set up to compare the layout characteristics of land use types under different scenarios in the future, and an optimized layout scheme is proposed. The results showed that: (1) In 2020, the areas of four land use functional zoning of the prohibited, restricted, key, and optimized development zones in Fenhe River Basin were 2491.76 km2, 6445.99 km2, 16325 km2, and 14477 km2, respectively. The net carbon emission of the basin is 2002.46 × 104 t. The prohibited development zone is the carbon sink area of the basin, and the total carbon absorption is 0.76×104 t. The remaining three areas are carbon source areas, and the total carbon emission is 2003.22 × 104 t. (2) In 2030, the carbon balance of land use in each scenario from high to low is low- carbon development priority, ecological protection priority, cultivated land protection priority, natural development priority, and economic development priority. (3) In 2030, under different scenarios, in addition to the relatively reasonable land use structure of the prohibited development zone, the restricted development zone still needs to appropriately reduce the proportion of cultivated land and construction land in the area. To support the coordinated development of land use, production, living conditions, and ecological functions and to accomplish low-carbon land use goals, the key and optimal development zones should take arable grassland development into consideration.
Subjects: Geosciences >> Cartography submitted time 2022-12-20 Cooperative journals: 《干旱区研究》
Abstract：
The study of snowline altitude changes at the end of the melting season is helpful to predict future trends of snow systems in order to understand the regional and global climate changes. The remote sensing extraction method of region snowline altitude was developed based on the Google Earth Engine and Landsat satellite data. From 1991 to 2021, the snowline altitude at the end of the melting season in the four basins of the Tianshan Mountains was extracted. The variation characteristics of snowline altitude and its relationship with meteorological factors were carefully and accurately estimated. The results were as follows: (1) the extended snowline altitude at the end of the melting season correlated well with the snow cover extent (minimum) at end of the melting season, which was extracted by Sentinel-2. The overall accuracy was 91.6%, and the Kappa coefficient was higher than 0.9. The regional snowline altitude at the end of the melting season was accurately obtained with this model. (2) Generally, the snowline altitude at the end of the melting season in the study area showed an obvious increasing trend over the last 30 years. The increase rate was between 2.7 m·a-1 and 6.4 m·a-1 . The rise rate of the snowline altitude in the Manas River Basin was the fastest (6.4 m·a-1 ), while the rise rate of the snowline altitude in the Akeyazi River Basin was the slowest (2.7 m·a-1 ). (3) The summer temperature was the main factor that affected the change in the snowline altitude at the end of the melting season in the study area (P < 0.05), while the effect of precipitation was relatively weak.
Subjects: Geosciences >> Cartography submitted time 2019-11-15 Cooperative journals: 《干旱区地理》
Abstract：研究气温对植被覆盖度和ET (Evapotranspiration，ET)的影响，对干旱区应对气候变化、维系生态系统稳定具有重要意义。基于阿勒泰地区及周边7个气象站，CRU数据集中的气温数据及MODIS ET数据，采用Mann-Kendall非参数检验、植被盖度反演等方法，对阿勒泰地区气温变化对植被覆盖度及ET的影响进行了研究。结果表明：（1）在1901—2016年过去的116 a间，阿勒泰地区年平均气温以0.18 ℃·(10 a)-1速率增加，在1982年由突变前的2.2 ℃增加到突变后的3.5 ℃。（2）2000—2017年阿勒泰地区植被覆盖度变化的空间差异明显，植被覆盖度增加的面积与降低的面积总体相当；全区66.71%的区域植被覆盖度变化与气温呈负相关，而呈正相关的比例仅占18.55%，且全区气温变暖而盖度降低区域的占比达31.71%。（3）2000—2016年阿勒泰地区ET总体呈降低趋势，整个区域61.65%的面积温度降低、ET降低，而19.92%的区域表现为温度增加而植被ET降低。
Subjects: Geosciences >> Cartography submitted time 2019-01-11 Cooperative journals: 《干旱区地理》
Abstract：泥沙是影响河流健康和水环境的重要因素之一，受气候变化和人类活动的影响，流域水文要素和下垫面条件发生了较大变化，尤其是实施大规模的水土保持措施后，部分河流的泥沙含量大幅减少，但在河西内陆河流域发源于祁连山西端的疏勒河流域，受降水条件和人类活动的影响，河流泥沙呈增加趋势。本文应用疏勒河流域实测长系列水文资料，采用水文统计法、差积曲线法、趋势检验法、突变检验法、非线性复相关模型法等方法，分析了流域泥沙时空分布规律及水沙关系，结果表明：疏勒河干流昌马堡站年输沙量为333.5×104 t，至下游潘家庄站减少到223.5×104 t；党河党城湾站年输沙量为76.56×104 t，至下游沙枣园站增加到121.3×104 t；疏勒河干流输沙量主要集中在汛期7～8月，占全年的81.9 %～84.0 %，党河流域输沙量主要集中在4-8月，占全年的92.3 %；流域泥沙变化总体呈增加趋势，突变点1998年以后，年输沙量增加了86.3 %～148.2 %。建立了潘家庄站降水～泥沙、径流～泥沙以及年输沙量～年径流量～年最大洪峰流量关系模型，相关关系较好，相关系数达到0.717～0.858。流域出山口以上对泥沙的影响因素主要是降水，出山口以下主要是修建水库、水电站、引水工程、河道采砂等人类活动影响。随着国家对内陆河流域祁连山和河西走廊的日益关注，以及全国河长制的推行，河流生态健康已经提上日程，研究疏勒河流域泥沙分布规律及水沙关系，对国家实施西部生态安全战略、区域生态环境修复治理、水资源可持续利用等具有重要意义。
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