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1.
新疆伊犁地区野果林的群落特征及保护   总被引:4,自引:1,他引:3  
新疆伊犁地区是我国野果林分布的主要地段.通过野外调查和资料收集,共获得67个野果林群落样方,分析了新疆伊犁地区野果林的群落结构及其分布特征.结果表明:野果林林下物种丰富,共记录维管束植物46科141属207种.群落分类将野果林划分为野核桃林、野苹果林、野杏林和野生樱桃李林4种类型.野杏林和野生樱桃李林的物种丰富度显著高...  相似文献   

2.
新疆野苹果资源保护对策探讨   总被引:6,自引:1,他引:5  
新疆野苹果是现代栽培苹果的原始祖先,也是苹果育种中的重要材料,具有极为重要的保护价值.但近几年由于对新疆野苹果林的不合理利用和管理不善等原因,导致了新疆野苹果资源的持续减少.根据实地调查和文献资料,对新疆野苹果林的主要威胁因素及其保护和研究状况进行了评估,认为超载放牧、不合理的嫁接改造、病虫危害及过度的果实采收是造成新疆野苹果林持续衰退的主要因素.现有保护区数量少、保护范围小、保护手段单一,难以满足对野苹果资源的保护需要.据此,提出了加强保护区和保护小区建设、健全野苹果林保护体系、加强新疆野苹果种质资源的收集和异地保护、促进野苹果林群落的更新恢复和保护、加强对野苹果林演替动态及更新机制等方面的建议.  相似文献   

3.
新疆沙漠空间分布格局与类型结构   总被引:3,自引:0,他引:3  
在对新疆沙漠区域环境特点分析的基础上,基于新疆1[JP18]∶[JP]1 000 000数字地貌图和TM影像数据及Google Earth等资料,利用GIS技术,编制了新疆沙漠分片图与沙漠类型分布图,对新疆沙漠空间分布与类型结构进行了分析。结果表明:① 新疆共有577块沙漠,可以划分为35片区。按照区域可分为塔里木盆地沙漠区、准噶尔盆地沙漠区、阿尔泰山沙漠区、准噶尔西部山沙漠区、昆仑山-阿尔金山沙漠区、天山沙漠区6个区;② 新疆沙漠面积达428 977.14 km2,占新疆总面积的26.12%;沙漠分布广泛,平原、丘陵和山地均有分布,但各区域的沙漠面积相差悬殊;沙漠在空间上呈聚集分布,主要分布在塔里木盆地和准噶尔盆地;沙漠景观破碎化程度具有很大空间差异性,在塔里木盆地和准噶尔盆地中面积较大沙漠的破碎化程度低,而在山地与两大盆地的过渡地带面积较小的沙漠破碎化程度较高。③ 新疆沙漠具有独特的地貌类型、稳定性和类型丰富度等类型结构,地貌类型以沙丘和沙垄为主,沙漠植被覆盖度差,以流动性沙丘和流动性沙垄为主,多数沙漠的类型丰富度贫乏,只有少数沙漠类型数量可以达到中等乃至极丰富。  相似文献   

4.
The distribution and migration of houbara bustard in China was studied by range investigation and tracking through PTT satellite transmitter from 1997 to 2004. The houbara bustard occurs in the Junggar Basin, north part of Tacheng Basin and valley of Ulungur river in northern Xinjiang, southern part of Turpan Basin and Barkol in eastern Xinjiang. In Inner Mongolia, the houbara bustard occurs in Urathouqi, Alxahouqi and Ejinaqi. In Gansu province, the houbara bustard occurs in Wuwei, Minqin and Shandan. The whole range is not contiguous area. Houbara bastard started migration from Junggar Basin in northern Xinjiang, Turpan Basin and Barkol in eastern Xin-jiang, Wuwei in western Gansu Province and Bayan Nur in western Inner Mongolia in the middle of September. Flying to the west and northwest, via Junggar Basin and area between Bole and Habahe in northern Xinjiang, entered Kazakhstan, they turned toward southwest, passed Uzbekistan and Turkmenistan, arrived in Arabia Bay of southern Iran or flied over Afghanistan, arrived in southern Pakistan for wintering. The whole migration usually took 35 ± 13 days covering a distance of 4 800-7 000 km. In the next year, houbara went back to the breeding grounds in China through the same routes at the beginning of March. However, it took the birds 64 ± 17 days to finish the spring migration. They arrived in breeding site between middle of April and late May. The sub-adults arrived later and did not breed.  相似文献   

5.
新疆野生动植物物种丰富度的分布格局   总被引:1,自引:0,他引:1  
新疆野生动植物种类丰富,有野生维管束植物3 637种、鸟类425种和哺乳动物154种.在广泛收集这些植物和动物分布资料的基础上,绘制了新疆动植物物种丰富度分布图,分析这些物种丰富度分布之间的关系,并得到物种丰富度分布的热点地区.新疆动植物丰富度北疆高于南疆,西部高于东部;阿尔泰山、天山西部和准噶尔西部山地是物种丰富度分...  相似文献   

6.
QIU Dong 《干旱区科学》2022,14(12):1413-1439
Malus sieversii (wild apple tree), only distributed in the Tianshan Mountains in Central Asia, is a tertiary relic species and an ancestral species of cultivated apples. However, existing natural populations of wild apple trees have been declining. To date, spatiotemporal variations in the growth status of declining wild apple trees and influencing factors in the narrow valley areas in the Tianshan Mountains remain unclear. In this study, field investigation and sampling were carried out in three years (2016-2018) at four elevations (1300, 1400, 1500, and 1600 m) in the Qiaolakesai Valley (a typical longitudinal narrow valley in the Yili River Valley) of the western Tianshan Mountains in Xinyuan County, Xinjiang Uygur Autonomous Region, China. Projective coverage, dead branch percentage, and 18 twig traits (these 20 parameters were collectively referred to as plant traits) were determined to comprehensively reflect the growth status of declining wild apple trees. The values of dead branch percentage ranged from 36% to 59%, with a mean of 40%. Year generally showed higher impact on plant traits than elevation. In 2017 and 2018, projective coverage, leaf size, leaf nitrogen concentration, and nitrogen to phosphorous ratio were markedly higher than those in 2016. However, dead branch percentage and leaf and stem phosphorous concentrations showed the opposite trend. Most of the topological parameters of plant trait networks differed in the three years, but the strength of trait-trait association increased year by year. The mean difference between day and night temperatures (MDT), annual accumulative precipitation, soil electrical conductivity, and soil pH had the greatest impact on the plant trait matrix. The growth status of declining wild apple trees was directly and positively affected by MDT and leaf size. In conclusion, the growth of declining wild apple trees distributed in the narrow valley areas was more sensitive to interannual environmental changes than elevation changes. The results are of great significance for further revealing the decline mechanism of wild apple trees in the Tianshan Mountains.  相似文献   

7.
伊犁谷地盐渍土的类型和特性   总被引:1,自引:0,他引:1  
伊犁谷地是新疆盐渍土分布面积最小的地区,据新疆荒地考察队资料:该区有盐渍化土壤2.76万公顷,盐渍土1.79万公顷,仅占谷地平原区面积的2.28%和1.48%;而塔里木盆地北部和南部的盐渍化土壤、盐渍土分别占该平原区面积的11.39%、30.81%和38.00%、35.12%。 1.盐渍土的形成及主要特点伊犁谷地位处我国境内天山西段,东南北三面环山,地势东高西低,东窄西宽,形似楔形,使西来湿润气流长驱直入东部谷地,而来自准噶尔盆地的干冷气流和塔里木盆地的干热  相似文献   

8.
准葛尔盆地南缘沙尘暴、大风气候特征分析   总被引:1,自引:0,他引:1  
选取1953~2006年准葛尔盆地南缘石河子垦区3个地面观测站的资料,对比分析了沙尘暴、大风的时空分布特征,探讨沙尘暴和大风之间的关系及沙尘暴发生时的最多风向和最小风速指标。结果表明:准葛尔盆地南缘石河子垦区沙尘暴与大风的地理分布刚好相反,沙尘暴多的地方大风较少,北部莫索湾沙漠边缘一带为沙尘暴高发区;但有着基本一致的气候变化趋势。沙尘暴发生时的最多风向为西北风,引起沙尘暴的最小风速指标大于10m/s。  相似文献   

9.
研究新疆天山野果林建群种新疆野苹果(Malus sieversii)光合生理特性,对于该种群保育及其生态功能评价具有重要意义。通过野外测定新疆新源天然野果林中不同径级64株新疆野苹果南向枝条上部叶和下部叶饱和光强下的净光合速率(A)、气孔导度(gs)和比叶面积(SLA)。结果表明:随着径级增加,上部叶和下部叶的Aarea、Amass显著增加。gs随径级的增加先增加再降低,在径级Ⅲ(树干0.5 m高处直径25~35 cm)时达最大。上部叶比下部叶有着高的Aarea、Amass和gs。回归分析表明:随着树干直径增加,Aarea和gs呈二次多项式增加,Amass呈线性增加。SLA随径级增加变化不显著,上部叶SLA显著低于下部叶。上部叶的Aarea高于下部叶,但由于SLA显著减小,在Amass上两者差异减小。随gs增加,上部叶Aarea呈幂函数增加,下部叶Aarea呈二次多项式增加。   相似文献   

10.
Causes of recurring drought patterns in Xinjiang, China   总被引:2,自引:0,他引:2  
Xinjiang Uygur Autonomous Region of China, with its unique topography and geographical location receives very less precipitation in summer as compared with other parts of China. The region is a land locked where moisture is supplied only by westerly winds from Atlantic Ocean as the moisture coming from Indian Ocean is mostly blocked by the Himalayas Range and the Tibetan plateau. In such a scenario, Xinjiang faces severe drought conditions offering significant challenges to water management. In this paper, we analyzed the drought periods in Xinjiang and discussed the various factors that might have influenced precipitation over the past forty-four years. For this purpose, we defined three periods of consecutive four years for high and low precipitation intensities. The average observed precipitation was 1.05 mm/day and 0.7 mm/day in summer (June-July-August) for the Tianshan Mountain region and Junggar Basin of Xinjiang, respectively. The drought conditions indicated that high sea level pressure, wind divergence and low convection were the prominent features that caused the droughts, which often do not allow the condensation process to coagulate the tiny water droplets into relatively large raindrops reducing the amount of precipitation in the region. The period of 1983-1986 is the lowest precipitation interval indicating the severe drought in the western Xinjiang (i.e western Tianshan Mountain region), for which, less moisture availability, strong divergence and less convection could be the most influencing factors.  相似文献   

11.
近50a西北干旱区气候变化趋势及对荒漠化的影响   总被引:7,自引:2,他引:5  
西北干旱区干旱少雨,生态环境脆弱,土地荒漠化严重。本文根据近1951-2000年的逐月平均气温和月降水量资料研究了我国西北干旱区气候变化趋势,并结合近年来西北干旱区地表径流量变化,分析其对准噶尔盆地、塔里木盆地、河西走廊和柴达木盆地土地荒漠化影响。研究结果表明:(1)近50a西北干旱区气温都升高,变暖最显著的是北疆和柴达木盆地。降水量有增加趋势,其中南疆降水量增加趋势最大。北疆蒸发量有减少趋势外,其他区蒸发量都在增加,尤其南疆蒸发量增加趋势最大。(2)近50a来由于气候变暖,使蒸发量增大,塔克拉马干沙漠、河西走廊沙漠区和柴达木沙漠区的干旱危害加剧,这必然导致沙漠化的易发和其进程的加速。北疆气温升高,降水量增加,而蒸发量减少,有利于古尔班通古特沙漠区沙漠化进程的减缓。(3)气候变化和地表径流量变化有利于准噶尔盆地和塔里木盆地的土地荒漠化逆转,而使河西走廊和柴达木盆地的土地荒漠化发展迅速。  相似文献   

12.
为明确江苏地区Q型烟粉虱的遗传多样性及其入侵来源,基于mt DNA COI基因序列,对2010、2011年采自江苏13个市的Q型烟粉虱种群进行了单倍型分析。结果显示,江苏地区Q型烟粉虱有4个单倍型,分别为单倍型Q1、Q2、Q3、Q4,不同单倍型的分布和发生频率不同,其中单倍型Q2是13个地理种群的共享单倍型,2010、2011年的发生频率均超过50%;单倍型Q1和Q3分别是部分地理种群的共享单倍型,发生频率较低;单倍型Q4仅在扬州种群中出现,发生频率最低;单倍型Q1和Q3亲缘关系较近,单倍型Q2和Q4亲缘关系较近,表明各地理种群间既有一定的基因交流,也存在一定程度的遗传分化;系统发育分析表明,江苏地区的Q型烟粉虱可能来源于西部地中海地区,与日本的Q型烟粉虱具有相同的入侵来源。  相似文献   

13.
区域旅游资源类型的甄别及其空间整合是旅游规划的重要基础性环节。文中以新疆伊犁河谷地区为案例,梳理区域旅游资源类型,在此基础上分析了竞争型旅游资源类型和旅游资源市场竞争力,并以竞争型资源为主要吸引物提出旅游资源的空间区域整合开发方案。以期对该区域旅游业竞争力的提升,实现新的资源配置和产品组合,使得区域旅游资源效益最大化有所裨益。  相似文献   

14.
黄刺蛾是新疆重要入侵检疫性害虫之一。为明确其检疫性,运用GARP生态位模型,预测黄刺蛾在新疆的潜在地理分布。结果表明:新疆存在一部分地区适宜黄刺蛾生存区域,主要位于环塔里木盆地地区,吐鲁番盆地、伊犁地区、阿勒泰地区、乌鲁木齐及昌吉州地区。建议应加强监测,防止其扩散。  相似文献   

15.
 Projecting future water demand, especially in terms of agricultural irrigation demand, as well as identifying high-risk areas and establishing appropriate water demand management has become increasingly important in China. Climate scenarios provide opportunities to predict future irrigation requirements (IRs). We examined changes in IRs and agricultural drought in response to rising greenhouse gas concentrations in China using eight global climate models from the Intergovernmental Panel on Climate Change Fourth Assessment Report. In this research, Northeast China, the North China Plain and the Yarlung Tsangpo River Valley area in southeastern Tibet were estimated to receive more precipitation in the future, whereas Southeast and Northwest China, especially the Junggar and Tarim basins in Xinjiang Uygur autonomous region, will receive less precipitation. IRs will undergo a significant increase in summer (June–August), especially in July, whereas the smallest increase was predicted to occur in autumn (September–November). Middle rice was identified as the greatest contributor to the increase in total IRs. The areas predicted to experience significant increases in IRs include Northwest China (the Tarim and Junggar basins in Xinjiang Uygur autonomous region, the Hexi Corridor in Gansu province and the Guanzhong Plain in Shaanxi province), Southeast China (especially Fujian province), and Southwest China (Yarlung Tsangpo River Valley area in Tibet and the Sichuan Basin).  相似文献   

16.
Owing to global climatic changes and human activities,the lakes have changed dramatically in the Junggar Basin of Xinjiang in recent 50 years. Based on the remote sensing images from Beijing Satellite No.1 in 2006 together with the measured topographical data in 1999 and other data since the 1950s,this paper analyzes mainly the features of landforms around the Manas Lake and the changes of feeding sources of the lake. The results are as follows:(1) Tectonic movement brought about the fundamental geomorphological basis for lacustrine evolution,and the Manas Lake is one of small lakes broken up from the Old Manas Lake due to tectonic movement and drought climate; the Manas Lake had existed before the Manas River flowed into it in 1915. The geomorphologic evidences for evolution of the Manas Lake include:(a) Diluvial fans and old channels at the north of the lake indicate that the rivers originating from the north mountains of the Junggar Basin had fed the Old Manas Lake and now still feed the lake as seasonal rivers; (b) The Old Manas Lake was fed by many rivers originating from the mountains,except for the Manas River,from the evidence of small lakes around the Manas Lake,old channels,alluvial fans,etc.; (c) The elevations of the alluvial and diluvial fans are near to the 280 m a.s.l. and all of the small lakes and lacustrine plains are within the range of the 280 m a.s.l.,which may prove that the elevation of the Old Manas Lake was about 280 m a.s.l.; (d) Core analysis of the Manas Lake area also indicates that the Manas Lake has existed since Late Pleistocene epoch. (2) Analysis on the feeding relations between the lakes and the lacustrine evolution shows that human activities are one of main driving forces of the lacustrine evolution in recent 50 years,and it is the precondition of restoring and maintaining the lacutrine wetlands in the study area to satisfy the feeding of the Baiyang and Manas rivers to the Manas Lake.  相似文献   

17.
人类活动和自然环境的胁迫加速了中亚地区新疆野苹果[Malus sieversii(Ledeb.)Roem.]种群栖息环境的丧失,新疆野苹果种群面积和生存力趋于下降。本文以第三纪孑遗植物新疆野苹果(M. sieversii)为研究对象,野外系统调查新疆野苹果种群的生存现状,比较新疆伊犁和哈萨克斯坦分布的新疆野苹果种群年龄结构及果实产量,对两地当前新疆野苹果种群变化进行了分析。研究结果显示:当前伊犁地区和20世纪70年代哈萨克斯坦新疆野苹果种群的龄级结构主要以中龄(15~50 cm)树为主,而幼龄(0~15 cm)与老龄(50~75 cm)树较少。1969年和1970年哈萨克斯坦的新疆野苹果种群生存力最弱,种群为衰退型(Deevey-Ⅲ),但其产量较高;2016年和2017年伊犁的新疆野苹果种群生存力相对较弱,种群趋于衰退(Deevey-Ⅲ),产量较低;2013年哈萨克斯坦新疆野苹果种群生存力相对最强,种群最稳定(Deevey-Ⅱ);幼龄个体的缺乏是新疆野苹果种群趋于衰退的关键因子。目前在哈萨克斯坦新疆野苹果保护区内需进行适当放牧干扰,以扩大种子的传播,提高种子的萌发;新疆地区以建立保护区为主,杜绝新疆野苹果的采收和降低野果林内的割草强度,以保护幼苗的生存数量,提高新疆野苹果的种子库,加快新疆野苹果种群更新。  相似文献   

18.
新疆人工灌溉绿洲的形成和发展演变   总被引:4,自引:4,他引:4  
新疆人工灌溉绿洲形成的自然条件取决于水文、地貌、土壤和植被,并与社会经济因素和生产活动方式、生产发展水平及人口增长密切相关.塔里木盆地的古绿洲多分布在河流中下游三角洲上;老绿洲多在冲积扇中下部和冲积平原;新绿洲则多在老绿洲的外围和边缘.吐鲁番盆地在依靠火焰山泉水灌溉时,绿洲在火焰山以南;18世纪以后,绿洲主要分布在依靠坎儿井灌溉的地方;20世纪50年代后,实行渠、库、井联合灌溉,绿洲原地不断扩大.天山北麓平原,绿洲最初在交通和军事据点,后发展成一条河一小块绿洲.1949年后由于农垦事业的发展,才将小块绿洲扩大连接成绿洲带.伊犁河谷,起初依靠山溪小河灌溉,绿洲只是小块分布在伊宁和霍城.此后,引伊犁河水,开发的土地多在河谷平原的阶地上,整个伊犁河谷成为新疆最大的绿洲之一.  相似文献   

19.
天山野果林生态系统受损现状及其保护   总被引:11,自引:2,他引:9  
天山自然资源丰富,是新疆人民世世代代赖以生存和发展的天然宝库,野果林生态系统是其重要的组成部分, 国干旱  相似文献   

20.
为研究不同国家和地区苹果蠹蛾Cydia pomonella种群的遗传多样性,对采自我国新疆维吾尔自治区和黑龙江省,以及德国、法国和西班牙等欧洲国家的11个种群共60个苹果蠹蛾个体进行基因组重测序,有效测序样本数为56个,共获得8 455 843个群体单碱基突变(single nucleotide polymorphism,SNP)位点。利用SNP数据进行了苹果蠹蛾群体遗传进化树的构建、主成分分析以及遗传结构分析。结果显示,入侵我国黑龙江省的苹果蠹蛾与德国BD种群更为接近,我国新疆维吾尔自治区与黑龙江省苹果蠹蛾种群有一定的分化,前者种群遗传多样性更低。表明我国东北地区和西北地区的苹果蠹蛾种群具有不同的遗传多样性特征,入侵我国的苹果蠹蛾种群可能来源于欧洲。  相似文献   

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