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51.
1IntroductionLandscapestructurewithintheMuUsDesert,asemiaridregionofnortheasternChina,isthebasicfocusofthisstudyconcerningla...  相似文献   
52.
w(SOC)(SOC为土壤有机碳,soil organic carbon)及其分布状况显著受到土壤PSD(particle-size distribution,粒径分布)和有机质相互胶结方式的差异影响,而w(SOC)可反映土壤结构优劣程度,表征土壤肥力状况及碳库饱和度.以乌兰布和沙漠沙冬青、花棒、猫头刺、白刺和梭梭灌丛下0~100 cm深度风沙土为研究对象,通过野外分层采样与室内测试,采用多重分形理论探讨土壤特性和w(SOC)分布特征及其相互关系,反映土壤结构及肥力状况.结果表明:① 不同灌丛下的土壤均具有良好的分形特征,并且灌丛可通过降低风速,使≤ 50 μm的优质颗粒在周围表层土壤沉降,而优质颗粒数量与w(SOC)、D0(粒径分布范围)及D1(分布均匀程度)极显著正相关(P < 0.01),与D1/D0(分布离散程度)极显著负相关(P < 0.01);② 各灌丛下w(SOC)的大小关系与D1、D0相似但与D1/D0完全相反,即w(SOC)可表征PSD状况进而反映土壤结构优劣程度,并且在沙冬青灌丛的>20~30、>60~80 cm土层出现两次峰值,分别为11.958、11.928 g/kg;③ 对D0的扩大及D1/D0的降低程度以沙冬青灌丛最为明显,但对D1的降低程度则以花棒灌丛最为明显.研究显示,多重分形理论可很好地描述乌兰布和沙漠风沙土性质,并且适生灌丛中沙冬青及花棒可更好地改善土壤颗粒及SOC特征,故可通过种植二者局部改良土壤及增加碳库饱和度.   相似文献   
53.
Abstract

The main purpose of this study is to put forward a reasonable idea of the general protection for Singing Sand Mountain and Crescent Moon Spring, a rare and unique desert wonder, and of sustainable tourism development based on the research on the ecological environment around. Methods of documentation, case study and comparison were employed. Finally, aiming at solving the problems of natural environment and those existing after the exploitation of Singing Sand Mountain and Crescent Moon Spring the author puts forward three measures: the comprehensive treatment for Crescent Moon Spring (broadening resources of water and reducing expenditures, checking the decreasing depth of Crescent Moon Spring, and improving the geographical environment), the general protection envisions for Singing Sand Mountain and Crescent Moon Spring and establishing a dynamic monitoring and early-warning system of regional ecosystem.  相似文献   
54.
The main purpose of this study is to put forward a reasonable idea of the general protection for Singing Sand Mountain and Crescent Moon Spring, a rare and unique desert wonder, and of sustainable tourism development based on the research on the ecological environment around. Methods of documentation, case study and comparison were employed. Finally, aiming at solving the problems of natural environment and those existing after the exploitation of Singing Sand Mountain and Crescent Moon Spring the author puts forward three measures: the comprehensive treatment for Crescent Moon Spring (broadening resources of water and reducing expenditures, checking the decreasing depth of Crescent Moon Spring, and improving the geographical environment), the general protection envisions for Singing Sand Mountain and Crescent Moon Spring and establishing a dynamic monitoring and early-warning system of regional ecosystem.  相似文献   
55.
Four automatic weather stations (AWS) were installed on the slopes and foot areas of the Tianshan and Kunlun Mountains along a longitude of 80 degrees east: (1) Taglak 2400 m a.s.l., (2) Aksu 1000 m, (3) Kartash 2800 m, and (4) Qira 1700 m. These two slopes face the Taklimakan Desert. Tagliak lies on the southern slope of Tianshan, and Kartash on the northern slope of Kunlun. The meteorological characteristics of the mountainous regions were investigated using surface data obtained during an intensive observation period (IOP) in spring 2002. It was found that visibility on the slopes decreases in the daytime, and there is no relationship between visibility and wind speed in the mountainous areas. Two snow layers containing dust particles were observed in the snow cover in Taglak during the IOP in spring 2003. These results suggest that a warm air parcel containing aeolian dust climbs over the slopes of the mountainous areas, and dust particles in the mountainous areas are transported from the foot areas.  相似文献   
56.
内蒙古乌兰布和沙漠旅游资源开发研究   总被引:1,自引:0,他引:1  
旅游业对于开发区域丰富的资源及提高区域经济竞争力有着不可忽视的作用。沙漠是一种特殊的旅游资源,国际上沙漠旅游正成为一种新兴的旅游方式。积极开发沙漠旅游资源,既利于区域人地关系的和谐演进,又利于全面推进区域的可持续发展。以内蒙古乌兰布和沙漠旅游资源为研究对象,通过对沙漠中自然和人文资源的分析,探讨了沙漠旅游资源在开发利用中的优势和劣势。最后对乌兰布和沙漠旅游可持续发展的对策进行了探讨,并结合区情,提出了开发的具体措施,目的在于全面推进乌兰布和沙漠旅游业的发展。  相似文献   
57.
Disturbance of flora from utility construction tends to generate new plant growth. This growth changes productivity, diversity, and stability. Although the enhancement of vegetation may balance out the biomass destroyed by the original disturbance, it often adversely affects the quality of the vegetation. Percentage composition of the dominant long-lived perennials combined with quantitative measures are used to assess longterm effects of utility corridor construction. Differential effects of enhancement of vegetation are found along road edges, enhancement under wires of powerlines, and over trenches dug for pipelines. Areas under powerline pylons seem to receive the greatest damage and also show the most variable recovery of vegetation. Significant recovery rates are noticeable where the time span between year of construction has allowed for considerable regrowth of the older corridor. Recovery rates depend on soil type, landform, and other physical features of the disturbed sites. Drastic disturbance in one area or transect site may impede vegetation recovery, whereas slight disturbance might enhance vegetation in another, tending to offset the effect of the drastic disturbance. Disturbed areas and control areas may appear to have similar vegetation covers, biomasses, and densities, but these similarities often vanish when one examines qualitative aspects, such as proportion of long-lived species and presence of characteristic dominants.  相似文献   
58.
59.
古尔班通古特沙漠生物结皮中土壤微生物垂直分布特征   总被引:13,自引:0,他引:13  
对新疆古尔班通古特沙漠主要沙丘类型———沙垄的不同部位、不同类型生物结皮中土壤微生物数量变化特征进行研究,结果表明:(1)微生物总数从垄顶至垄间低地呈递增趋势,在沙垄不同部位0~20cm土层中的垂直分布有差异.(2)土壤微生物各类群数量垂直变化规律为:细菌数量在垄顶0~10cm土层中递减,到10~20cm有所回升;在迎风坡和背风坡的0~10cm土层中递增,到10~20cm有所下降;在垄间低地0~20cm土层中呈递增趋势.放线菌数量在各部位均随土层加深而递减.真菌数量在垄顶和迎风坡0~20cm土层中的垂直变化与细菌在垄顶的垂直变化一致,在垄间低地和背风坡,真菌数量均在2~5cm土层中出现峰值,然后随土层加深递减.(3)微生物类群的组成表现为:细菌数量>放线菌数量>真菌数量.在垄间低地细菌所占微生物总数比例相对垄顶有所增加,而放线菌和真菌相应减少.(4)土壤微生物的数量变化特征与生物结皮的类型、分布以及土壤有机质含量等因子有一定相关性.图5表1参34  相似文献   
60.
景观生态学与荒漠生态环境监测   总被引:2,自引:0,他引:2  
通过对景观生态的阐述,在讨论荒漠生态环境监测的概念、对象、内容、方法和目的的基础上,分析了景观生态学成为荒漠生态环境监测理论和实践的基础的可能性和必要性,指出景观生态学在荒漠生态环境监测中的应用大有可为。  相似文献   
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