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1.
中国沙漠化研究的理论与实践 总被引：43，自引：2，他引：43
中国的沙漠化研究的理论与实践在过去的十多年里取得了一些成果。据此,本文对沙漠化的概念、成因、过程、指征、后果、发展趋势及其治理等方面进行扼要的介绍。研究表明,沙漠化是一种人为活动与自然资源、环境不相协调所产生的以风沙活动为主要标志的土地退化过程。我国北方沙漠化土地的蔓延速率从50年代末期至70年代中期的年均1560km2发展到近十多年来的年均2100km2;实践证明,沙漠化土地作为一种土地资源可以通过合理的整治过程而恢复其原有的生产潜力。 相似文献
2.
Change trends for desertified lands in the Horqin Sandy Land at the beginning of the twenty-first century 总被引：2，自引：1，他引：1
Zhiwen Han Tao Wang Changzhen Yan Yubin Liu Lichao Liu Aimin Li Heqiang Du 《Environmental Earth Sciences》2010,59(8):1749-1757
The dynamics of desertification in the Horqin Sandy Land between 2000 and 2005 were analyzed using Landsat TM/ETM images and
the data-processing function of geographical information software. The results showed that the extent of desertified land
decreased at a rate of slightly more than 0.1 km2 year−1, from 22,423.1 km2 in 2000 to 22,422.4 km2 in 2005, indicating that desertification has been controlled in this area and that desert areas may be approaching a steady
state. The dynamics of desertification differed among land types. Desertification decreased most obviously in areas of previous
desert land. The area in which desertification was ameliorated was higher than the area that underwent further degradation,
but non-desertified land (113.3 km2) deteriorated at a rate of 22.7 km2 year−1 during this period. This significant change requires careful attention by managers in the study area. 相似文献
3.
荒漠化是指人类历史时期以来,由于人类不合理的经济活动和脆弱生态环境相互作用造成土地生产力下降,土地资源丧失,地表呈现类似荒漠景观的土地退化过程。在中国北方荒漠化形成因素中过度放牧占30．1％,过度农垦占26．9％,过度樵采占32．7％,水资源利用不当占96％,工矿交通建设中不注意环境保护占0．7％,在地区上以北方农牧交错及旱农地区荒漠化最为严重。要采取因地制宜措施和建立健全而完善的治理实施系统以达到生态、经济和社会三个效益的目的。 相似文献
4.
本文根据类似荒漠境况的出现是判断荒漠化发生与否的重要标志这一原则,并结合在中国南方开展的一些研究,对湿润地区的荒漠化进行了初步的探讨。研究表明,湿润地区的荒漠化并不包含所有存在侵蚀作用的退化土地,而专指人为侵蚀作用导致的出现了具类似荒漠境况的退化土地。中国南方湿润地区土地荒漠化分布最显著的特征为斑点状分布于丘陵山区或河、湖、海滨的冲积平原,面积为1．98×105km2,其中流水作用导致的荒漠化面积为1．78×105km2,风力作用的为0．11×105km2,其它0．09×105km2。自然因素,特别是气候和地貌因素对荒漠化的形成和发展起着积极的影响作用,但不是决定作用。人为不合理的经济活动,才是造成荒漠化的主要原因。文章最后还简要介绍了湿润地区荒漠化的防治问题。 相似文献
5.
Relationships between rocky desertification and spatial pattern of land use in typical karst area,Southwest China 总被引：7，自引：4，他引：3
Yongjun Jiang Linli Li Chris Groves Daoxian Yuan Pat Kambesis 《Environmental Earth Sciences》2009,59(4):881-890
Karst rocky desertification is a typical type of land degradation in the Southwest China. An attempt was made to study quantitatively
the relationships between rocky desertification and spatial pattern of land use through applying spatial analysis of Geographical
Information System in Nandong underground river system, a typical karst area, Southwest China. The spatial distribution of
rocky desertification and spatial pattern of land use were obtained from interpreting Landsat Images in Nandong area in 2007
by supervised classifications, and verified and rectified through field survey. The results indicate that: (1) the total land
deserted area covers 378.3 km2, or 23.4% of the total area, of which intense, moderate and slight rocky desertification covers 269.46, 54.2, and 54.63 km2, respectively, in Nandong area. (2) There is an obvious effect of spatial pattern of land use on rocky desertification. With
the increase of elevation and slope, there is a higher occurrence ratio of rocky desertification in the cultivated land and
grass land. Also, more than half of total rocky desertification was dominated within the areas of 4 km from the construction
land, and 97% of total rocky desertification was dominated within the areas of 10 km from the construction land in Nandong
area. And what can be known from the data is that the primary effect distance of human on rocky desertification from the construction
land is 4 km, and the farthest effect distance of human on rocky desertification from the construction land is 10 km in Nandong
area. 相似文献
6.
7.
本文在毛乌素沙地景观分类、制图及景观动态研究的基础上,分析了50年代以来毛乌素沙地荒漠化发展状况及其时空特征,并对其扩展原因进行了分析和探讨。结果表明,50年代以来,该地区荒漠化整体上处于迅速扩展之中,只是某些局部地方植被得到一定程度的恢复;荒漠化扩展存在明显的空间和时间差异：西北部纯牧区扩展速度远远高于东部和南部半农半牧地区,70年代末至90年代初扩展速度远远低于50年代末至70年代末;荒漠化的迅速扩展主要是由于不合理的人类活动造成的,气候波动也有一定影响。 相似文献
8.
Driving forces responsible for aeolian desertification in the source region of the Yangtze River from 1975 to 2005 总被引：1，自引：1，他引：0
The Yangtze River is the China’s longest river and the third-longest river in the world. The river’s source region in the
Qinghai-Tibet Plateau is especially sensitive to global environmental change because of its high elevation and cold environment.
Under the influence of global warming, aeolian desertified land has expanded rapidly in this area. To assess the trends in
aeolian desertification from 1975 to 2005, remote-sensing and GIS technology were used to monitor the extent of aeolian desertification
in 1975, 1990, 2000, and 2005. The data sources included Landsat multi-spectral scanner images acquired in 1975, Enhanced
Thematic Mapper (ETM+) images acquired in 2000, and Thematic Mapper (TM) images acquired in 1990 and 2005. Images recorded
between June and October were selected, when vegetation grew well, because aeolian desertified land was more easily recognized
during this period. Thematic maps, including land use and geomorphologic maps, were used as supplementary data. Aeolian desertification
maps (1:100000) were produced for each year from the Landsat images through visual interpretation. The area of aeolian desertified
land increased by 2,678.43 km2 from 1975 to 2005, accounting for 8.8% of the total area of aeolian desertified land in 1975, an increase of 89.28 km2 a−1. Increasing mean annual temperature and the combination of a dry, cold, and windy climate in winter and spring were mainly
responsible for the expansion of desertified land. 相似文献
9.
The coastal zone of the Sagar island has been studied. The island has been subjected to erosion by natural processes and to
a little extent by anthropogenic activities over a long period. Major landforms identified in the coastal area of the Sagar
island are the mud flats/salt marshes, sandy beaches/dunes and mangroves. The foreshore sediments are characterized by silty,
slightly sandy mud, slightly silty sand and silty sand. Samples 500 m inland from high waterline are silty slightly sandy
mud, and by clayey slightly sandy mud. The extent of coastline changes are made by comparing the topographic maps of 1967
and satellite imageries of 1996, 1998 and 1999. Between 1967 and 1999 about 29.8 km2 of the island has been eroded and the accreted area is only 6.03 km2. Between 1996 and 1998 the area underwent erosion of 13.64 km2 while accretion was 0.48 km2. From 1998 to 1999, 3.26 km2 additional area was eroded with meager accretion. Erosion from 1997 to 1999 was estimated at 0.74 km2 /year; however, from 1996 to 1999, the erosion rate was calculated as 5.47 km2/year. The areas severely affected by erosion are the northeastern, southwestern and southeastern faces of the island. As
a consequence of coastal erosion, the mud flats/salt marshes, sandy beaches/dunes and mangroves have been eroded considerably.
Deposition is experienced mainly on the western and southern part of the island. The island is built primarily by silt and
clay, which can more easily be eroded by the waves, tides and cyclonic activities than a sandy coast. Historic sea level rises
accompanied by land subsidence lead to differing rates of erosion at several pockets, thus periodically establishing new erosion
planes. 相似文献
10.
An analysis, over historical times, of the influence of natural factors such as climate, geological activity, existing landforms,
and the activity of aeolian sands on the desertification of oases and other lands in the Heihe River basin of northwestern
China revealed that desertification occurred more or less quickly according to whether the prevailing climate was cold or
warm, respectively. In the 1990s, the area of desertified lands in the lower reaches of the Heihe River (Ejin region) was
29.1% greater than in the mid 1980s. However, the rate of desertification in the middle reaches of the Heihe River basin was
relatively slower, only 9.4% from 1949 to 1990 (or 0.27% per year). Since 1990, the rate of desertification has been stable.
By 2000, the total area of land desertification in the mid to lower reaches of the Heihe River basin was 13,508.4 km2, or 11.8% of the region monitored. Of the total land desertification area, the regions of Linze, Gaotai, Sunan, Jiuquan,
Jia Yuguan, and Jinta accounted for 1.70, 1.71, 1.43, 0.85, 0.28, and 9.39%, respectively, whereas the Ejin region’s 11,434.64 km2 accounted for 84.65%, indicating that land desertification in the lower Heihe River basin was particularly severe. The causes
responsible for the occurrence and development of land desertification in the Heihe River basin were analyzed. 相似文献
11.
Land degradation in the source region of the Yellow River, northeast Qinghai-Xizang Plateau: classification and evaluation 总被引：6，自引：0，他引：6
Land degradation imposes a great threat to the world. It is not merely an environmental issue, but also a social and economic problem. Land desertification is among the main aspects of environment changes in the source region of the Yellow River. Previous studies focused on water resource utilization and soil erosion, but land degradation in the source region of the Yellow River even the whole Qinghai-Xizang Plateau received little attention. Based on the data obtained by field investigation and TM satellite images of 2000, this study provides the classification and evaluation information of the land degradation in the source region of the Yellow River. There are six types of land degradation in this region: water erosion in the northern mountains around the Gonghe Basin, sandy desertification in the Gonghe Basin and Upland Plain Area, aridization in the lower reaches, salinization in the Gonghe Basin, vegetation degradation in the intramontance basin and freezing and thawing erosion in the high mountains. The total degraded area is 34,429.6 km2, making up 37.5% of the land in the study area. Finally, land degradation in the source region of the Yellow River was evaluated according to changes in the physical structure and chemical component of soils, land productivity, secondary soil salt and water conditions. 相似文献
12.
Land-use change and its environmental impact in the Heihe River Basin, arid northwestern China 总被引：3，自引：0，他引：3
Rapid land-use change has taken place in many arid and semi-arid regions of China over the last decade as the result of demand for food for its growing population. The Heihe River Basin, a typical inland river basin of temperate arid zone in northwestern China, was investigated to assess land-use change dynamics by the combined use of satellite remote sensing and geographical information systems (GIS), and to explore the interaction between these changes and the environment. Images were classified into six land-use types: cropland, forestland, grassland, water, urban or built-up land, and barren land. The objectives were to assess and analyze landscape change of land use/cover in Heihe River Basin over 15 years from 1987 to 2002. The results show that (1) grassland and barren land increase greatly by 22.3, and 268.2 km2, respectively, but water area decreased rapidly by 247.2 km2 in the upper reaches of Heihe River Basin; (2) cropland and urban or built-up land increased greatly by 174.9, and 64.6 km2, respectively, but grassland decreased rapidly by 210.3 km2 in the middle reaches of Heihe River Basin; and (3) barren land increased largely by 397.4 km2, but grassland degraded seriously and water area decreased obviously by 313.3, and 21.7 km2, respectively in the lower reaches of Heihe River Basin. These results show that significant changes in land-use occur within the whole basin over the study period and cause severe environmental degradation, such as water environmental changes (including surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality), land desertification and salinization, and vegetation degeneracy. 相似文献
13.
荒漠化目前已成为威胁全球生态环境的主要问题。我国北方地区风蚀作用强烈,是土地沙质荒漠化问题最为突出的地区。以沙漠、沙地分布较广的北方6省(区)为研究区,利用遥感技术获取2010—2018年研究区沙质荒漠化演化特征,并将气象、地质等因素进行综合分析,探讨毛乌素沙地、科尔沁沙地沙质荒漠化变化原因。遥感解译结果表明: 2018年北方地区沙质荒漠化土地共35.08万km2,其中重度沙质荒漠化面积11.92万km2,中度沙质荒漠化13.54万km2,轻度沙质荒漠化9.62万km2,主要分布于内蒙古自治区和新疆维吾尔自治区; 2010—2018年,北方地区沙质荒漠化土地面积减少0.73万km2,其中,新疆维吾尔自治区沙质荒漠化面积减少0.48万km2,内蒙古自治区减少0.19万km2,同时有2.78万km2沙质荒漠化土地程度减轻。以毛乌素沙地和科尔沁沙地为典型研究区,对比两沙地生态地质条件差异,总结了沙质荒漠化好转、加重的原因。研究认为,毛乌素沙地应降低人类活动干扰的影响,以自然恢复为主; 科尔沁沙地应加强地下水资源管理,优化植被结构,进一步推进退耕还林、退耕还草工作。研究成果为我国北方沙质荒漠化地区生态保护修复提供了科学参考。 相似文献
14.
“荒漠化”是当今全球关注的一个重大的社会、经济和环境问题。《公约》为全球防治荒漠化的联合行动提供了一种全新的方式。本文运用生物控制理论中正负反馈回路的自我调节和自我加强作用分析了荒漠化过程的内在机制;用耗散结构理论分析了系统实现良性循环的途径,并提出我国防治荒漠化应遵循的4个原则：1)调节农林牧水工复合生态系统的结构和功能;2)实行“生态系统管理”,促进系统内的良性循环;3)传统知识与现代科学技术相结合;4)完善政策措施和加强科学管理。 相似文献
15.
Spatial pattern of Karst rock desertification in the Middle of Guizhou Province,Southwestern China 总被引：13，自引：0，他引：13
Karst rocky desertification is a typical type of land degradation in the Southwestern China. It has great ecological and economical
implications for the local people. Landsat images from the middle of Guizhou Province collected in 1974, 1993 and 2001 were
used for change detection of the pattern of Karst rocky desertification. The results show the following findings: (1) Desertification
area expanded drastically in 27 years, at an increasing rate about 116.2 km2/year. (2) High areas (900–1,500 m) are the most affected. (3) Areas with the slope <5° or >25° are also easily tend to be
Karst rocky deserted. (4) The process of Karst rocky desertification is nearly irreversible. Few areas of Karst rocky desertification
could be meliorated to non-desertification land. (5) Most of the degraded lands are located in the south and the central of
the study region, and the meliorated land areas are sparsely located in the east and the west part of the region. All these
findings would provide bases for the decision-making of the local government to improve the Karst rocky desertification 相似文献
16.
广西壮族自治区是我国岩溶石漠化较为严重的省区之一,监测其石漠化发展演变趋势与开展治理工作是一项长期任务。根据全国生态环境遥感调查与监测项目完成的石漠化遥感调查结果,分析了广西境内1999—2008年间石漠化的分布和演化情况,探讨了石漠化变化与整治措施及社会经济发展的关联性。研究结果表明,截至2008年,广西石漠化面积达1.703万km2,约占全区总面积的7%,占碳酸盐岩分布区总面积的20.85%; 其中,轻度、中度和重度石漠化面积分别占石漠化总面积的58.70%、29.02%和12.28%,以轻度和中度石漠化为主。9年间,全区石漠化总面积减少了1.026万km2,年均减少面积0.114万km2,年均增长率为-5.10%,石漠化总体面积减少,程度减轻,呈明显好转态势。石漠化的演变趋势与近年来一系列环境保护政策的落实、产业经济结构的变化、农民人均收入的增长等密切相关,如退耕还林措施、农业人口转移、农户家庭收入构成变化及沼气灶推广等均在减缓石漠化发展中取得了很好效果。然而,由于受地质背景、自然环境和人口因素的制约,广西石漠化治理的难点依然存在,任务仍很艰巨。 相似文献
17.
Rocky desertification and its causes in karst areas: a case study in Yongshun County,Hunan Province,China 总被引：9，自引：0，他引：9
Rocky desertification, a process of land degradation characterized by soil erosion and bedrock exposure, is one of the most
serious land degradation problems in karst areas, and is regarded as an obstacle to local sustainable development. It is well
known that human activities can accelerate rocky desertification; however, the effects of climate change on rocky desertification
in karst areas are still unclear. This study focused on the effects of temperature and precipitation changes and human activities
on rocky desertification in karst areas to determine the impacts of climate change and human disturbances on rocky desertification.
Areas of different level of rocky desertification were obtained from Landsat TM (1987) and Landsat ETM+ (2000) images. The
results show that, although the total desertification area increased by only 1.27% between 1987 and 2000, 17.73% of the slightly
desertified land had degraded to a moderate or intense level, 2.01 and 15.71%, respectively. Meanwhile, between 1987 and 2000,
the air temperature increased by 0.7°C, and precipitation increased by 170 mm. Statistical results indicate that the increase
in precipitation was caused by heavy rainfall. In addition, under the interactive influences of heavy rainfall and temperature,
the average karst dissolution rate was about 87 m3 km−2 a−1 during the 14 years in the study area. Further analysis indicated that rocky desertification was positively related with
the increase in temperature and precipitation and especially with the heavy rainfall events. Climate change accelerated rocky
desertification in the karst areas.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
18.
中国东北平原西部土地荒漠化,主要表现为土地沙漠化和土地盐碱化,它属于荒漠化的两种类型。东北 平原西部分布着科尔沁沙地和松嫩沙地,前者是全国五大沙漠之一。文章全面、系统地对该地区编制了 1∶1000000荒漠化图和量算出土地沙漠化面积。东北平原西部土地沙漠化面积为72280.6km2,占土地总面积的 22.2%。自20世纪50年代至80年代末,土地沙漠化面积迅速扩大,平均每年以1.5%～3.7%的速度递增;自9 年代以来,沙漠化呈现出逆转趋势,但就总体而言,沙漠化发展仍然大于逆转。东北平原西部土地盐碱化面积 33850.79km2,占土地总面积10.44%,主要分布在松嫩平原,面积为23329.19km2,占土地总面积15.2%,它是世 界上苏打盐碱化土壤的三大片之一,土地盐碱化每年以1.4%～2.5%速率正在发展。所以,该地区的土地荒漠化 不仅制约着当地农、牧业和农村经济的发展,影响周围和毗邻国家的生态环境安全,而且已危及当地人民的生存。 东北平原西部荒漠化的形成有自然因素和人为因素,前者有物源和气候变化等原因,后者有草原超载过牧、滥 垦、滥伐滥櫵、乱挖,河流上中游修建水库等原因,以及冻融作用的特殊原因,致使荒漠化形成和发展。文章总结了 该地区沙漠化正、逆过程的演变,并提出荒漠化的治理应根据荒漠化 相似文献
19.
Temporal and spatial changes of karst rocky desertification in ecological reconstruction region of Southwest China 总被引：2，自引：1，他引：1
Qiyong Yang Zhongcheng Jiang Daoxian Yuan Zulu Ma Yunqiu Xie 《Environmental Earth Sciences》2014,72(11):4483-4489
Karst rocky desertification (KRD), as a process of soil degradation, is a limiting factor on enhancing the life condition of people in Southwest China. Fortunately, Chinese governments at different levels had taken it seriously, and the ‘Green for Grain’ program was initiated to treat and protect the fragile environment. In order to assess the dynamic change of KRD and improve the treatment of it in the future, Pingguo County, one of the ‘one hundred typical counties for karst rocky desertification control in China,’ was chosen as the study area. The results indicated that the evolution process of KRD landforms in the county might be divided into two phases: degradation phase (1994–2001) and ecological reconstruction phase (2001–2009). In the degradation phase, the area of non-KRD landform decreased from 1,132.02 km2 in 1994 to 1,056.42 km2 in 2001. In this phase, the area of non-KRD landform lost 5.51 % to KRD landforms, which mainly transferred to slight KRD landform with an area of 35.55 km2 counting for 3.14 %. In another hand, the area of non-KRD gained 27.85 km2, mainly from the slight KRD landform. As a result the area of non-KRD was reduced, meaning that the evolution of KRD became serious. In this phrase, the dynamic change degree of the slight KRD landform was the minimum, and the area of it was the largest among the three KRD landforms. Therefore, transition of slight KRD landform was the main transition type in this phase. The area of slight KRD landforms increased 38.77 km2 in the county, which mostly took place in the middle and southwest karst regions. In ecological reconstruction phase, the area of non-KRD landform increased to 1,091.90 km2 in 2009. In this phase, non-KRD landform gained an area of 22.82 km2 and lost an area of 26.73 km2, major of which from or to the slight KRD landform. Therefore, the area of non-KRD landform was increased, implying that the evolution of KRD became alleviated. In this phase, transition of slight KRD landform was also the dominant transition type. The decreased area of slight KRD landform was the largest among severe, moderate and slight KRD cases in the southwest karst region, where the ecological reconstruction projects were initiated. The efficient degrees of KRD landforms in southwest karst region were the largest in the four karst regions in this county. This study results may provide a consultant for rocky desertification control and ecological restoration in the future. 相似文献
20.
朱刚 《中国地质灾害与防治学报》2021,32(6):90-97
应用“3S”技术与土壤化学方法,对毛乌素沙地榆林市境内区域的沙质荒漠化土地进行了近45年来变化研究与生态修复效果分析,研究结果表明:研究区土地的沙质荒漠化强度以轻度、中度为主,治理方式以人工修复为主;1975—2019年沙质荒漠化的分布面积与强度呈现先快速发展而后逆转的变化特征。其中,1975—2007年沙质荒漠化的发展与过度放牧、荒地开垦及矿产资源开发等人类活动及强度密切相关。2007—2019年的逆转与生态调控政策及治理工程的实施密切相关。人工修复地区的土壤养分含量优于自然修复地区,在同等背景的自然修复条件下,不同成因的沙质荒漠化土地土壤养分含量有一定区别。采用人工修复与自然修复相结合的方式,以人工修复促进植被自然修复能力,是研究区有效的生态修复方式。 相似文献