输水对干旱区生态恢复的作用——以塔里木河下游为例

在塔里木河下游生态环境本底状况调查的基础上,通过大量的监测资料,应用河道水力学、地下水动力学、植被生态学以及系统分析与优化方法,对5次应急输水植被生态响应效应进行了全面系统地评价,科学地确定了合理的生态修复目标和下游河道输水与区间水量优化配置方案。为创建和完善干旱区受损生态系统输水、修复与重建的评价体系奠定了理论和实践基础,也为塔里木河流域综合治理提供了重要的技术支撑。图4,表5,参6。

1980-2020年中亚干旱区生态系统水分利用效率数据集

水分利用效率(WUE)表征了陆地生态系统水分耗散与碳固存之间的耦合关系。了解水分利用效率时空动态及其对复杂气候变化的响应是应对未来气候变化和人为扰动的前提。生态模型方法被认为是评估区域大尺度生态系统碳水动态的有效方式。本研究基于干旱区生态系统模型(AEM),利用站点通量数据,通过对模型进行优化、校验、参数化,构建了一套中亚干旱区生态系统水分利用效率数据集。本数据集时间跨度为1980-2020年,涉及中亚针叶林、阔叶林、草地、深根灌木、非深根灌木以及农田等6种生态系统类型,区域包括中亚五国(哈萨克斯坦、乌兹别克斯坦、塔吉克斯坦、吉尔吉斯斯坦、土库曼斯坦)和中国的新疆地区。研究将模拟结果与实测站点数据进行了对比验证,发现模拟结果与实测结果高度一致。本数据集为全球变化背景下了解生态脆弱区碳水动态,维护生态系统稳定提供了数据支撑。

CASA模型的改进及在干旱区生态系统NPP估算中的应用

CASA模型是针对北美地区植被而建立的净第一性生产力(NPP)模型,当前,该模型已被广泛应用于陆地生态系统NPP的估算。由于模型是针对北美地区植被而建立,因此,模型在不同于北美地区应用时,其参数需要进行修正。现在已有一些关于CASA模型修正的研究,但修正均未体现干旱区特点。文中以甘肃省为例,在充分考虑干旱区特点基础上,从土地利用/覆盖类型的划分、最大光能利用率的取值、高精度气象数据的选择以及遥感影像数据的选择等方面,对利用CASA模型进行干旱区生态系统NPP估算过程进行改进,使该模型更适用于干旱区。利用改进后的CASA模型模拟了甘肃省各土地利用/覆盖类型的NPP,获得了较高的精度,研究利于探索干旱区生态系统碳计量方法。

干旱区地下水生态水位研究进展

地下水位是维系干旱区生态系统稳定的主要限制因子,而地下水位又同时受到干旱区气候变化因素、植被特征因素及土壤理化性质因素的影响。在评述干旱区地下水生态水位概念的发展和内涵的基础上,分析了在地下水生态水位变化影响因素方面所取得的研究进展,总结了近年来在地下水生态水位研究领域的主要计算方法,进而结合干旱区在生态水文地质领域存在的主要科学问题,提出了未来研究的重点方向。

中国干旱区水资源利用与生态环境

世界上有1/3的面积干旱缺水,其遍布于亚非、拉美及澳大利亚的大部分地区。中国干旱区属于亚非干旱带的一部分,总面积在300万平方公里以上,约占我国总土地面积的1/3,遍及蒙、宁、青、甘、新、藏等六个省区。 世界上许多干旱区是人类文明的发祥地,自古以来。

干旱区农业生态园策划、规划、设计理念初探——以新疆尉犁县生态园为例

将策划理论与旅游规划相结合 ,以尉犁生态园为例 ,集高科技农业示范、干旱区生态恢复研究、农业观光旅游于一体 ,并结合现代化农业培训和农业科技推广等的协调发展 ,尤其注重突出干旱区特色。从策划的角度对规划的背景、原则、设计及构思与进行讨论 ,以求对干旱区生态观光农业规划的发展有所启益。

塔里木河下游生态输水对植被和地下水位的影响

由于近 5 0a来人类不合理的资源开发 ,造成塔里木河下游的生态环境问题日趋严峻 .为拯救下游绿色走廊和改善下游环境 ,于 2 0 0 0年 7月始 ,实施了塔里木河下游应急生态输水工程 ,水流到达台特玛湖 .本文根据 2a来在塔里木河下游的监测结果 ,通过对下游天然植被的一些生态指标的变化和输水后地下水位变化等资料进行对比分析 ,发现随着输水工程的进行 ,距输水河道一定范围内地下水位升高明显 .相应地 ,下游植被的生态响应也很显著 ,沿河岸许多种草本植被又重新出现 ,而一些耐旱乔、灌木随着生境的改变 ,长势也出现明显好转 ,主要表现在植被盖度、植物多样性指数和丰富度指数的提高以及胡杨冠幅的加大 .同时 ,研究结果表明 ,截止 2 0 0 2年 9月 ,在塔里木河下游中段 ,生态输水对地下水影响范围为 80 0m ,天然植被恢复的范围为 70 0m .由于环境条件的差异 ,在不同区段的影响范围不一样 。

基于遥感和Penman-Monteith模型的内陆河流域不同生态系统蒸散发估算

遥感数据具有很好的时空连续性,它是区域蒸散发通量估算的有效方法。引入了一个简单的具有生物物理基础的Penman-Monteith(P-M)模型,分别利用黑河流域高寒草地阿柔站和干旱区农田盈科站2008—2009年的气象数据和MODIS(Moderate Resolution Imaging Spectroradiometer)叶面积指数(LAI),实现了2008—2009年日蒸散发的估算,并同时实现了对植被蒸腾和土壤蒸发的分别估算。结果表明,利用P-M公式模拟的蒸散发与实测的蒸散发具有较好的一致性,日蒸散发模拟的决定系数(R2)超过0.8。估算的高寒草甸和干旱区农田玉米全年平均的蒸腾分别为0.78 mm/d和1.20 mm/d,分别占总蒸散发的60%和61%,土壤蒸发分别为0.53和0.77 mm/d,占总蒸发的40%和39%。可见两种生态系统的作物蒸腾均强于土壤蒸发,同时农田玉米蒸腾强于高寒草甸蒸腾。研究结果证明了基于遥感的P-M公式可以很好地实现对高寒草地和干旱区农田生态系统蒸散发的估算。通过考虑土壤水分变化对气孔导度的影响,可以提高模型对农田蒸散发的模拟精度。

重构绿洲生态系统的理性思考——以疏勒河流域酒泉移民区为例

二十世纪80年代以来,甘肃省有计划、大规模移民河西走廊的疏勒河流域,规模达15万多人。境流域内本已脆弱的生态环境在人为干预之下发生诸多巨大变化,流域内经济、社会和生态建设的持续发展面临严峻考验。如何科学发展、合理规划、有序开发,重新建构人与环境和谐发展的绿洲生态系统,有效做到生存与发展、保护与开发之间的平衡,成为流域内经济、社会发展必须面对的现实问题。

干旱区城市化对生态系统碳库的影响——以乌鲁木齐市为例

城市化是影响区域生态系统碳循环的主要原因,也是评估生态系统碳循环的最大不确定因素。论文利用1990与2010年Landsat TM数据,基于V-I-S城市土地覆被模型和决策树分类法,获得乌鲁木齐土地变化时空格局;结合野外实测数据和文献检索得到研究区不同土地覆被类型的土壤与植被碳密度,估算了城市土地变化对生态系统碳库的影响。结果表明:1)1990—2010年间,乌鲁木齐城市不透水地表(impervious surface areas,ISA)以中部南部内部填充与北部扩张的形式约增加62%,主要占用农田(27%)与荒漠(62%)。2)乌鲁木齐市生态系统碳库主体(95%)分布在土壤中,城市土地覆被变化导致约25%的碳库损失,由农田、裸土/残存荒漠以及城市绿地转变为ISA解释了68%的土壤有机碳和63%的植被碳损失量,其空间分布与ISA的扩张相一致。城市植被及其土壤具有较高的碳密度,合理的城市规划可以抵消部分因土地变化而损失的生态系统碳。

干旱区受损生态系统恢复与生态效应分析-以塔里木河下游为例

在对塔里木河下游生态环境本底状况调查的基础上，通过大量的监测资料，应用河道水力学、地下水动力学、植被生态学以及系统分析与优化方法，对五次应急输水植被生态响应效应，进行了全面系统地评价。科学地确定了合理的生态修复目标和下游河道输水与区间水量优化配置方案。为创建和完善干旱区受损生态系统输水、修复与重建的评价体系奠定了理论和实践基础，也为塔里木河流域综合治理提供了重要的技术支撑。

干旱区琵琶柴群落细根周转对土壤有机碳循环的贡献

尽管干旱区生态系统的脆弱性受到了广泛的关注,但目前关于干旱区植物细根有机碳与土壤碳循环关系的研究还比较少见。在2010年整个生长季节内,采用土钻法和内生长法,对新疆干旱区的琵琶柴(Reaumuria soongorica)群落土壤特性、细根的生物量月动态、生产量和周转进行了研究。结果表明:琵琶柴群落表层土壤含水量最低,土壤含水量表现出从浅层到深层逐渐增加的趋势;而表层土壤的有机碳含量最高,随着土壤深度的加深,有机碳含量逐渐降低。细根生物量的月平均值为54.51g·m–2,群落细根生产量在82.76–136.21g·m–2·a–1之间,琵琶柴群落的细根周转率为2.08times·a–1,通过细根死亡进入土壤中的有机碳为17g·m–2·a–1。这些结果表明:由于灌丛细根高的周转速率,细根是干旱区土壤有机碳输入的重要部分。

简评《中国干旱区景观生态学研究进展》

由肖笃宁、王根绪、王让会研究员编著的《中国干旱区景观生态学研究进展》一书，于2003年12月由新疆人民出版社出版发行。全书60万字，503页，由中国科学院新疆生态与地理研究所所长张小雷为该书作序。《中国干旱区景观生态学研究进展》是我国第一部全面反映中国干旱区景观生态学的研究成果，是中国科学院新疆生态与地理研究所“绿洲学者”计划和国家自然科学基金重大项目(90102004)的研究成果之一。该书的出版对推动我国干旱区景观生态学的研究具有重要意义。

塔里木河至孔雀河生态输水连通方案分析与实践意义

河湖库水系连通对于干旱区优化水资源配置、提高供水保障能力、促进水生态文明建设具有重要作用。为了增加孔雀河下游水量,节约水资源,基于孔雀河和塔里木河概况及水系关系对河道地貌、径流情况进行分析,并探讨了塔里木河向孔雀河生态输水连通方案,创新性地提出沿用现有的渭干塔里木河河道和生态输水支渠,经改造贯通进行输水,可节约水量、降低施工难度,且投资较少,为水系贯通和干旱区生态输水工程研究提供了借鉴。

2015年2月草业科学大事记 国际篇

4日英国环境食品与乡村事务部(Defra)更新一系列农业与环境变化监测指标。https://www.gov.uk/government/statistical-data-sets/agri-environment-indicators5日联合国粮农组织(FAO)公布,2015年1月份食品价格指数继续下滑,月平均数为182.7点,比2014年12月下降1.9%。http://www.fao.org/news/story/en/item/276661/icode/6日Bonachela等在Science撰文,研究表明白蚁可以增加干旱区生态系统应对气候变化时的稳定性。

Assessment of Ecosystem Services Value in Hotan Oasis, Xingjiang

[Objective] The study aimed to assess the ecosystem services value in Hotan Oasis, Xingjiang. [Method] The visual interpretation method was adopted to process TM/ETM＋ images based on field investigation in Hotan Oasis. These inter- pretation data, along with two periods of land use data, were reclassified to farm- land, forest, grassland and so on. Then, the ecosystem services value was calculat- ed and analyzed. [Result] Analysis indicated that the ecosystem services value had been increased by 30.44x108 Yuan （16.51%） in the study area during 1980-2010, which can be explained by the increase of glacier and snowfield distributed in the south mountain with the increase of annual precipitation. At the same time, the con- tribution rate of grassland to ecosystem services value had been decreased as a result of degradation of grassland and occupation from farmland. For the whole basin, the increase of ecosystem services value came from the upper reaches, while the ecosystem services value had been reduced in the middle and lower reaches. In the middle reaches, the reduction came mainly from wetland （-1.83x10s Yuan）, waters （-1.68x10s Yuan）, forest （-0.86x108 Yuan） and grassland （-0.80x108 Yuan）. But in the lower reaches, the ecosystem services values of waters, grassland and forest were -0.61 x108 Yuan, -0.24x108 Yuan, and -0.07x10s Yuan, respectively. [Conclusion] If some effective policies, such as the implementation of returning farm- land to forest and ceasing from farming to grazing, would be taken, the ecosystem degradation can be constrained and reversed in the northwest arid region.

Research on the extension of Tamarix shrubs resulted from devel-opment projects in arid area

Tamarix plant is widely distributed in the arid areas of China for its great tolerance of draught, salt and alkali and attracts more attention by its strong capacity in windbreak and sand-fixations. “Tamarix dunes” constitute special desert bio-landscape in arid area. During last several decades,Tamarix shrubs declined and “Tamarix dunes” were also severely destroyed due to the land exploitation and serious deforestation, etc. From the 1980s until now, the extending phenomenon ofTamarix shrubs caused by developmental projects such as building highway, railway was studied in the western dry area of China, including western section of Hexi Corridor of Gansu, railroads and highways around the two greatest basin in Xinjiang and interior regions in Gurbantonggut desert, through on-the-spot survey along the transportation lines and setting up sampling plots along the roads. It was found that large quantities ofTamarix plants grow in the catchment area of low-lying lands that were formed by bulldozer operation during road building period. The extension ofTamarix shrubs caused by engineering was similar to that of the other section of the area to some extent, but went beyond the original distribution. This extension is beneficial to the ecological restoration and re-vegetation of western region of China and plays an important role in control of the sandstorms and improvement of ecological environments. As a result, it is necessary to make a further study on the extending phenomenon ofTamarix shrubs and to seek approach to promote wider extension ofTamarix shrubs in suitable habitats. Key words Arid area - Tamarix - Development engineering - Vegetation extension CLC number S718.541 Document code A Article ID 1007-662X(2004)01-0045-04 Foundation Item: This study is supported by key projects of National Natural Science Foundation (39730100), National Foundation (30070640) and part of Project 973(G19990435).Biography: Huang Pei-You (1936-), Male, Professor in College of Life Science and Technology, Xinjiang University, Urumqi, 830046Responsible editor: Chai Ruihai

Effects of Land Use Change on Ecosystem Services in Arid Area Ecological Migration

Ecological migration is the process of increasing the population density in the immigration area and transferring the ecological pressure from emigration area to immigration area. This process may result in significant changes in land use and land cover in the area of immigration and have an important effect on ecosystem services. Therefore, scientifically revealing the effects and differentiation mechanisms of ecological migration on ecosystem services is becoming an important issue related to the implementation of the national ecological migration strategy in China. This study employed the Hongsibu District as a typical example of ecological migration. Hongsibu District is located in the central Ningxia steppe and desert steppe areas. Remote sensing data covering five periods from the period before ecological migration in 1995 and after migration in 2000, 2005, 2010, and 2015 was used to measure the value of ecosystem services(ESV). A geographical detector model and the value of ecosystem services model were used to diagnose the dynamic mechanism of the effects of land use change on ecosystem services. The results showed that: 1) The development of large-scale ecological resettlement has caused the area of cultivated land and urbanized land area to increase significantly in the area of immigration, while the grass area decreased significantly. 2) The overall value of the Hongsibu ecosystem services increased in a form of a ‘V'. Among them, during the period of 1995–2005, the overall ESV decreased and had an annual rate of change of-0.67%. During the period of development 2005–2015, the ESV increased steadily, with an annual rate of change of 0.79%. 3) The proportion and total ESV in soil formation and protection, waste treatment, and biodiversity conservation of the Hongsibu District decreased from 57.61% in 1995 to 56.17% in 2015, indicating that the region's ecological regulation function slightly decreased. 4) The ESV in the Hongsibu District, showed a low distribution pattern of ecosystem services increasing from northeast to southwest, and the capacity of three townships, Hongsibu, Taiyangshan, and Liuquan, to provide ecosystem services gradually declined over time. The ecological service function of Xinzhuangji Township and Dahe Township gradually improved. 5) The sensitivity index of the ESV of each land use type was less than 1, indicating that the environment lacks flexibility in providing a strong ESV index in Hongsibu, which shows that the research results are reliable and believable. 6) During the study period, the decisive force of the change of land use on ecosystem services in Hongsibu District was: grassland(0.9934), climate regulation(0.9413), soil formation and protection(0.9321) and waste treatment(0.9241).

Effects of arbuscular mycorrhizal fungi on the drought resistance of the mining area repair plant Sainfoin

To solve the problem of lack of water in arid areas and barren soil in the process of ecological restoration, the growth and drought resistance of Sainfoin （Onobrychis vidifolia Scop.） was studied by inoculation of AMF （arbuscular rnycorrhizal fungi）, under drought stress. The results show that the inoculation of AMF can significantly improve the growth and mycorrhizal infection rate of Sainfoin and accelerate the absorption of water and nutrients by the roots compared with uninoculated plants. On the 40th day under drought stress, the relative water content, total nitrogen and total phosphorus content of the leaves of inoculated plants increased by 7.27%, 4.21% and 2.40%, respectively, the osmotic adjustment property in plant cells was improved, the protective enzyme system was improved and membrane lipid peroxida- tion was reduced. The inoculation of AMF can slow down the damage from drought, improve the drought resistance of Sainfoin, and will be of great significance to the ecologic restoration in arid areas.