Subjects: Biology >> Botany submitted time 2023-03-28 Cooperative journals: 《干旱区研究》
Abstract： Plant death caused by drought is an important cause of species composition changes in terrestrial ecosystems. Revealing the influence of hydraulic triats on species distribution, which is of great theoretical significance for understanding plant drought adaptation, restoration and management of desert vegetation. In this study, the woody plants in the Ebinur Lake Wetland Nature Reserve were selected as subject to compare the variation characteristics of species abundance and hydraulic traits under soil drought gradient and analyze the relationship between hydraulic traits and species abundance distribution. Results showed that the sum of abundance (community density) of all species did not change significantly. However, the responses of different species abundance to drought stress were significantly different. With the increase in soil drought, the specific conductivity, quasi- steady conductivity, and Huber value increased; the water potential of branches and leaves decreased continuously, and the stem wood density did not change significantly. The difference of hydraulic triats among species changed with the degree of drought. Redundancy analysis and generalized additive model showed that 92.8% of the variation of desert woody plant abundance distribution pattern can be explained by the measured hydraulic triats. In addition, plant abundance increased with the quasi- steady conductivity, specific conductivity, Huber value, and water potential of branches and leaves but decreased with the increase in stem wood density. Therefore, the changes of the woody plant abundance distribution can be predicted using the changes of hydraulic traits.
Subjects: Geosciences >> Atmospheric Sciences submitted time 2023-03-28 Cooperative journals: 《干旱区研究》
Abstract： The status of air pollution in China has been recognized as a serious health concern in numerous academic circles. Air quality is an important factor for defining air pollution, and main pollutants used to evaluate its quality, include PM2.5, PM10, SO2, NO2, CO, and O3. Hotan is one of the oasis cities with severe air pollution crisis. The located in the southwest edge of Taklimakan Desert in the southernmost part of the Northwest Xinjiang province in China. The soil structure in this area is loose, dust storms are frequent, and particles carried by dust storms are heavily deposited, which result in an increase in the concentration of pollutants. Therefore, the air Pollution caused by these particles results in severe challenges. Different types of air pollutants have varied hazards to human health, for example, PM2.5 and PM10, which are the main air pollutants in Hotan City, cause serious human respiratory tract infections, and their sources are extensive, hazardious, and difficult to eliminate. The rapid economic development in recent years and the accelerated urbanization have aggravated the deterioration of air quality in Hotan City, posing a great threat to the physical and mental health of local residents. Therefore, understanding the characteristics of air quality and its potential health effects in Hotan City is crucial for controlling urban air pollution and improving local ecological environment. This study used the historical air quality data in Hotan from 2016 to 2021 to analyze the distribution characteristics of pollutants, to determine the relationship between air quality and potential human health effects, and to evaluate the correlation between pollution levels and air pollutants, such as PM2.5, PM10, SO2, NO2, CO, O3-8H, and AQI. The results showed that between 2016 and 2021, the concentration of O3-8H in two air pollution monitoring points in Hotan had an inverted U-shaped trend, while the concentration of other pollutants showed a U-shaped curve distribution. PM2.5 and PM10 were detected as the main pollutants throughout the year, and their concentrations were relatively high in spring. In addition, concentrations of SO2 and NO2 were high in autumn and winter, while those of CO and O3-8H were high in winter and summer, respectively. During the study period, the concentration of PM2.5 and SO2 decreased, while that of PM10 increased, but the overall air quality did not show significant improvement. The AQI value of air quality index in Hotan City was higher than the national second class level, and its value during the“unhealthy”air quality period was much higher than that during the“healthy”air quality, which suggested a high harmful potential to the physical and mental health of residents.
Subjects: Biology >> Botany submitted time 2022-12-20 Cooperative journals: 《干旱区研究》
Abstract：
Desert plants have developed unique leaf traits as part of their ecological response to long-term drought stress. We investigated the population characteristics of Tamarix ramosissima under different soil water conditions at the northern edge of the Tarim Basin and measured and analyzed its leaf structural and chemical traits, along with the main soil physicochemical properties, in this study. that the following was found: (1) soil water had a significant effect on several leaf traits of Tamarix ramosissima, including total nitrogen and phosphorus content, C:P, C:N, mean leaf thickness, and mean leaf area. (2) With the increase of soil water content, the N:P of Tamarix ramosissima leaves decreased, and its growth gradually changed from phosphoruslimited to nitrogen-limited. (3) There was a significant negative correlation between the total phosphorus content and C:P and N:P of Tamarix ramosissima leaves (P < 0.01) and a significant positive correlation between C:N and the mean leaf area (P < 0.05). The results indicate that soil water content is an important factor affecting the leaf functional traits of Tamarix ramosissima, and it adapts to the arid environment through the synergistic changes of some leaf traits. This study provides a basis for the evaluation of plant ecological adaptations in the ecological conservation and restoration processes in arid desert areas
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2018-11-08 Cooperative journals: 《干旱区研究》
Abstract：蒙古沙拐枣(Calligonum mongolicm Turcz)是中国荒漠植被的重要建群种，也是人工固沙造林的优选种。为了阐明气候变化及人类活动对其分布格局的影响，以119个蒙古沙拐枣地理分布信息和24个环境变量为基础，结合CMIP5的缩减全球模型数据，应用MaxEnt模型和ArcGIS空间分析技术，分别构建了不同气候情景及人类活动干扰下的蒙古沙拐枣适宜生境预测模型，定量展示了未来不同气候变化情景（RCP2.6，RCP 4.5，RCP 8.5）和人类活动干扰下蒙古沙拐枣在我国的分布格局变化。结果表明：训练集的AUC值为0.958,测试集的AUC值为0.951，MaxEnt模型的预测结果可靠；影响蒙古沙拐枣分布的主要气候因素是降水量和海拔；人类活动干扰下蒙古沙拐枣的适生比例由13.04%下降到9.57%，蒙古沙拐枣的繁殖栖息与人类活动成负相关。当前气候条件下蒙古沙拐枣总适生面积比例为13.04%，在RCP2.6、RCP4.5、RCP8.53种情景下至2050s，预测的总适生面积比例为13.36%、13.18%和14.78%；至2070s，预测的总适生面积比例为13.39%、12.76%和12.71%，适生范围及面积变化趋势各有差异，各级适生区面积及总适生面积有不同程度的增减，且在高浓度排放情景（RCP8.5）下响应最为明显。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2018-11-08 Cooperative journals: 《干旱区研究》
Abstract：以中国西北干旱荒漠区新疆艾比湖湿地自然保护区为研究区，选取对水分输入响应最敏感的短命植物狭果鹤虱，通过遮盖处理形成不遮盖（T1组）、半遮盖（T2组）与全遮盖（T3组）的3个凝结水梯度；研究凝结水的多少对狭果鹤虱的株高、冠幅、叶面积、叶片厚度、根长、根径、叶片相对含水量、叶片水势以及生物量分配的影响。结果表明：①在植株生长季中后期，随着凝结水量增加，植株高度、冠幅面积、叶面积、叶厚度、叶片相对含水率、净光合速率与气孔导度叶片水势均显著增加（P0.05）。②茎质比（SMR）在生物量分配中是一个比较稳定的性状，从T1~ T3组，变化幅度为3.0%～13.5%。个体植株叶质比（LMR）差异显著（P<0.05），根质比（RMR）均逐渐下降，但并未表现出显著差异。综合可知，干旱区中，狭果鹤虱的叶片可以吸收并利用凝结水，形态性状对水分极度敏感且具有较高变异性，主要通过改变地上性状、不改变地下性状的策略吸收利用大气凝结水。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2018-10-23 Cooperative journals: 《干旱区地理》
Abstract： 通过把握绿洲乡村聚落空间规律，揭示其影响机制，以期为西北边陲绿洲美丽乡村建设过程中的聚落管理和规划提供依据。基于GIS技术、计量统计方法和实地考察调查对新疆艾比湖流域绿洲乡村聚落空间格局及影响因素进行了分析。结果表明：（1）艾比湖流域绿洲乡村聚落整体为小规模-低密度-高核破碎化状态，呈现冲洪积扇平原-中低密度扇射型、河流两侧-低密度线状型和中高密度条带型及精河盆地-高密度团块型分布特色。（2）聚落局部规模分异明显，冷点区多为兵团团场连队，热点多为地方乡镇村庄。（3）聚落主要分布在海拔800 m以下、距河流2 km以内、距道路1 km以内区域，并深受政策制度影响。乡村聚落的发展更多地受制于人类的行为，然而，在艾比湖流域绿洲特殊的地形地貌、较大的海拔高程差以及博河、精河贯穿全区的自然条件下，乡村聚落格局及进一步发展受到限制。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2018-09-03 Cooperative journals: 《干旱区研究》
Abstract：利用新疆北部地区（下称北疆）41个气象站1961—2014年月平均气温资料，运用线性倾向率、滑动平均、基于ArcGIS的混合插值法、累积距平分析、Mann—Kendall突变检验，基于Matlab的Morlet小波分析等方法对北疆地区年及季节气温变化进行分析。结果表明：① 北疆地区年及季节平均气温出现多次冷暖波动，均呈显著增温趋势。其中，年及春、夏、秋季从20纪90年代以后增温显著，冬季20世纪80年代以后增温显著。② 北疆地区年平均气温倾向率为0.35 ℃•（10a）-1，增温幅度较大区域主要在准噶尔盆地、塔城地区及富蕴。③ 北疆地区年及四季平均气温均发生突变。其中，年、春、夏、秋季平均气温突变主要发生在20世纪90年代，冬季气温突变主要发生在70年代末。④ 北疆地区年平均气温在近54 a存在27 a主周期和14 a次周期，气温冷暖交替，周期表现具有全域性。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2018-06-10 Cooperative journals: 《干旱区研究》
Abstract： 维护生态环境脆弱的西北干旱区绿洲生态安全，是实现区域可持续发展的重要前提。以渭干河-库车河绿洲为研究区，从绿洲生态系统结构、功能、效益三方面构建评价指标体系；运用三角模型，对20052014年该绿洲生态安全状态和趋势进行测算分析；采用灰色关联分析法对影响该绿洲生态安全的因子进行分析。结果表明：①生态系统非结构性指数（NSI）总体呈逐年下降趋势；生态系统非功能性指数（NFI），呈现出波动起伏变化趋势；生态系统效益性指数（BI）总体上呈现持续上升趋势。②在20052014年期间，渭干河-库车河绿洲生态安全经历了不安全-弱安全两个状态，并呈现出逐渐向安全且稳定发展的趋势。③20052014年影响生态渭-库绿洲生态安全的主要因子是水土协调度和造林面积。研究结果将为维持及进一步改善该绿洲生态环境提供科学依据。
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