绿洲-荒漠交错带GSVAC水热传输可视化模拟系统的开发     

苏里坦  古力米热  宋郁东 《干旱区地理》2005,28(5):681-685

以天山北麓三工河流域绿洲．荒漠交错带为研究对象,以可视化开发语言Visual Basic 6．0作为主要开发工具,结合Access数据库,在传统SPAC系统原理的基础上开发了绿洲．荒漠交错带水热传输可视化模拟系统。该系统具备系统管理、数据输入、数据处理、信息查询、模型计算、地下水预测、图形绘制、结果输出等功能。充分考虑到实时预测的实际工作要求,在系统开发的过程中,力求将本项目所研制的各种预测方案集成为一个可实时业务化运行的软件系统。通过该模拟系统可预测绿洲-荒漠交错带植被蒸腾量、地表蒸发量和植被的根系吸水速率以及土壤水热动态传输过程,为绿洲-荒漠交错带地下潜水-土壤-植被-大气连续体中数据的管理、地下水的预测和GSVAC水热传输动态的计算机模拟提供了强大的软件环境。  相似文献   

中国北方农牧交错带耕地时空分异及驱动因素   总被引：1，自引：0，他引：1  

陶泽涪  王世清  孙丕苓  李凯迪  田文  韩潇潇 《干旱区地理》2022,45(1):153-163

耕地是保障国家粮食安全的重要载体.以中国北方农牧交错带为例,基于2000、2010、2020年3期遥感影像数据,综合运用转移矩阵、空间自相关分析、空间计量模型等方法系统分析了2000—2020年中国北方农牧交错带耕地时空分异特征及影响因素.研究结果表明:(1)2000—2020年中国北方农牧交错带耕地面积由268959...  相似文献   

荒漠绿洲交错区绿洲扩张与主要水文过程     

常学礼  李秀梅  白雪莲  季树新  王理想 《中国沙漠》2019,39(4):204-211

干旱区绿洲扩张主要发生在荒漠绿洲交错区（边缘区），绿洲空间变化对地表主要水文过程有直接影响。为了更好地了解这一变化机制，以绿洲与沙漠、荒漠、石质裸山交错分布的张掖绿洲边缘区为对象，采用F显著性检查和Mann-Kandell趋势分析对1987年以来绿洲与不同生态系统之间转化特点与趋势进行了研究，同时分析了绿洲扩张与主要水文过程关系。结果表明：1987—2017年来荒漠绿洲交错区不同生态系统空间变化主要发生在绿洲与沙漠和荒漠3种生态系统之间。转化以绿洲扩张为主要特点，累积扩张了1 696.86 hm²，平均每年56.56 hm²。其中，沙漠和荒漠分别转化了31.73 hm²·a^-1和24.83 hm²·a^-1。黑河中游干流用水量在研究时段内无显著性突变，多年平均为7.68×10⁸ m³，对绿洲面积扩张无显著性影响。但是地下水埋深在1998年发生显著性突变，突变周期发生在1997—2000年。总体来看，绿洲面积每增加520 hm²，地下水埋深下降1 m。地下水位埋深对绿洲扩张有显著性影响，是绿洲扩张最敏感的水文过程要素。  相似文献   

Comprehensive evaluation on the ecological function of groundwater in the Shiyang River watershed          下载免费PDF全文

Liu Min  Nie Zhen-long  Cao Le  Wang Li-fang  Lu Hui-xiong  Wang Zhe  Zhu Pu-cheng 《地下水科学与工程》2021,9(4):326-340

With an arid climate and shortage of water resources, the groundwater dependent ecosystems in the oasis–desert ecotone of the Shiyang River Watershed has been extremely damaged, and the water crisis in the oasis has become a major concern in the social and the scientific community. In this study, the degeneration characteristics of the groundwater ecological function was identified and comprehensive evaluated, based on groundwater depth data, vegetation quadrat and normalized difference vegetation index (NDVI) from Landsat program. The results showed that (1) the suitable groundwater depth for sustainable ecology in the Shiyang River Watershed is about 2-4 m; (2) the terms of degenerative, qualitative and disastrous stages of the groundwater ecological function are defined with the groundwater depths of about 5 m, 7 m and 10 m; (3) generally, the groundwater ecological function in the oasis-desert ecotone of the lower reaches of Shiyang River Watershed is weak with an area of 1 397.9 km² identified as the severe deterioration region, which accounted 74.7% of the total area. In the meantime, the percentages of the good, mild and moderate deterioration areas of groundwater ecological function are 3.5%, 5.5% and 16.3%, respectively, which were mainly distributed in the Qingtu lake area and the southeastern area of the Shoucheng town; (4) the degradation and shrinkage of natural oasis could be attributed to the dramatic groundwater decline, which is generally caused by irrational use of water and soil resources. This study could provide theoretical basis and scientific support for the decision-making in environmental management and ecological restoration of the Shiyang River Watershed.  相似文献   

阜康绿洲-荒漠交错带荒漠植被群落稳定性   总被引：8，自引：1，他引：8  

吕光辉  杜昕  杨建军  马媛  孟吉翔 《干旱区地理》2007,30(5):660-665

以阜康绿洲-荒漠交错带的荒漠植被为研究对象,利用样区内植被常规调查资料,改进了法国生态学家M.Godron从工业生产中发现并引入生态学研究中的稳定性测定方法,并将研究方法推广到植被群落的空间稳定性研究。根据这种方法,累积种类百分数与累积相对盖度比值越趋近于20/80群落就越稳定,在20/80这一点上是群落的稳定点。研究结果证实:从空间上看,绿洲-荒漠交错带不同植物群落稳定性不同;绿洲-荒漠交错带的荒漠植被群落稳定性受种间竞争、环境压力和干扰活动三个因素的影响,即使建群种相同的群落稳定性也会出现较大差异。  相似文献   

两湖平原城镇发展的空间过程   总被引：8，自引：0，他引：8  

龚胜生 《地理学报》1996,51(6):489-500

２０００多年来，两湖平原城市行政等级体系由两级演变为四级，分别经历了以江陵和武汉为首位城市的两在阶段；城市分布由低级均衡向高级均衡螺旋式上升发展，城市重心由西北向东南迁移；城市空间扩展呈圈层辐合型，丘陵与平原交错带的外缘中心城边缘效应强烈；城市空间结构为雏形的交通－市场最优原则复合型中心地体系。  相似文献   

The European research project on reed die-back and progression (EUREED)     

Hans Brix   《Limnologica》1999,29(1):5-10

Reeds (Phragmites australis (Cav.) Trin. ex Steudel) are dying back at a fast rate in sizeable areas of Europe, with significant impacts on important wetland functions (biodiversity, stability of river and lake margins, water quality) and local economy. EUREED is a European strategic fundamental research initiative that aims at analyzing the mechanisms which control the growth dynamics and stability of reed-dominated ecosystems, at modelling and predicting how the ecosystem is disturbed by human activities and climate change, and at developing remedial management options. Expected achievements include (i) assessment of the functional role of reed-dominated ecotones as nutrient accumulators and transformers and as sources for atmospheric greenhouse gases, (ii) an ecosystem model capable of predicting future changes in ecosystem functioning in relation to climatic conditions, trophic status and water table management, (iii) assessment of genetic diversity of reed populations and its relation to die-back, and (iv) development of management tools, including preventative and restorative measures in relation to die-back. The project is carried out by research groups with complimentary skills and expertise from nine European countries. A reference study site is selected in each country as the basis for the field studies. The reference sites cover boreal-mediterranean and oceanic-continental climatic gradients, and the observational and experimental studies at these sites will permit interpolation between sites and extrapolation of results to the European scale.  相似文献   

Carbon assimilation characteristics of plants in oasis-desert ecotone and their response to CO2 enrichment   总被引：2，自引：0，他引：2  

SU Peixi  CHEN Huaishun  AN Lizhe  LIU Xinmin 《中国科学D辑(英文版)》2004,47(Z1)

Six species of more than 20-year-old desert woody plants in the oasis-desert ecotone were selected for study. The results showed that: (1) in different growing seasons δ13 C values of assimilating organ varied between -14‰ and -16‰ for Haloxylon ammodendron (HA),-14‰ - -15‰ for Calligonum mongolicum (CM) and -25‰ - -28‰ for Caragana korshinskii (CK), Nitraria sphaerocarpa (NS) and Hedysarum scoparium (HS). (2) The net photosynthetic rate (Pn) of HA and CM was significantly higher than those of the other species. With the decrease in Pn for the six species, their intercellular CO2 concentration increased, but stomatal limitation value decreased under the intensive light. At the same time, the photochemical efficiency of PS Ⅱ dropped to different degrees. (3) The CO2 enrichment experiment demonstrated that, Pn of HA and CM increased to different extent under 450 μmol/mol, but their Pn reduced or approximated to the current condition under 650 μmol/mol. Under 450 μmol/mol the efficiency for solar energy utilization of CK and HS significantly reduced and under 650 μmol/mol their respiration rate exceeded photosynthesis rate. It can be concluded that HA and CM have some function of pathway for C4, but the other three species have the function for C3. The decline in their Pn is mainly caused by non-stomatal factors. HA, CM, CK and HS exhibited photoinhibition, which disappeared in a short time. This is a kind of positive readjustment to adapting to the desert environment. HA and CM can adapt to the high CO2 environment, but CKand HS cannot. With the rise in atmospheric CO2 concentration and climate warming, the latter two species in the oasis-desert ecotone may be gradually degraded or even disappear.  相似文献   

中国北方农牧交错区土地荒漠化的环境脆弱性机制分析   总被引：24，自引：5，他引：19  

张殿发  卞建民 《干旱区地理》2000,23(2):133-137

在综合分析中国北方农牧交错区自然 、经济和社会环境的基础上,概括出导致该地带土地 荒漠化的生态环境脆弱性机制：①脆弱的自然条件奠定了特殊的地貌格局和脆弱的地表物质基础,受东亚季风影响的气候条件是土地荒漠化的自然驱动力。②人类不合理的经济活动是土地荒漠化的直接推动力。③不利的社会因素加快了土地荒漠化的进程。  相似文献   

以生态系统管理为工具开展海岸带综合管理   总被引：5，自引：0，他引：5  

陈宝红  杨圣云  周秋麟 《台湾海峡》2005,24(1):122-130

本文从海岸带和海岸带综合管理的几大特征出发 (包括海岸带的中心地带———海 陆生态交错带、海岸带综合管理需要解决的主要问题———生态环境危机、海岸带综合管理的管理对象———社会 经济 自然复合生态系统等方面 ),提出生态学应成为海岸带综合管理的主要科学依据,海岸带综合管理应遵循并且充分运用生态学的理念和方法;文章通过对生态系统管理与海岸带综合管理的比较分析,指出生态系统管理正是生态学中有助于海岸带综合管理的最佳工具,海岸带综合管理应以生态系统管理为基础,并进一步阐述了生态系统管理在海岸带综合管理规划中的具体运用.  相似文献