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1.
21世纪西南岩溶石漠化演变特点及影响因素   总被引:17,自引:10,他引:7  
文章通过分析西南岩溶地区石漠化面积遥感调查结果和相关统计资料,揭示了21世纪以来石漠化时空演变特征和影响因素。2015年,我国西南岩溶地区石漠化总面积降至9.2万km2,石漠化演变的总趋势由21世纪以前的加剧变化为21世纪的逐渐减缓,而且,西南岩溶区石漠化程度显著变轻,由21世纪初的以重、中度石漠化为主演变为以轻、中度石漠化为主,危害最大的重度石漠化面积比例由38.08%降至15.31%,说明石漠化趋势得到有效遏制。但石漠化演变存在较大的区域差异,主要与国家实施植被修复工程力度、影响植被恢复的岩溶地貌类型、地下水开发程度、雨水资源以及区域经济条件密切相关。植被建设规划面积与石漠化减少面积成正比,生态经济条件相对较好的峰林平原和溶丘洼地石漠化治理效果最好,地下水开发和比较丰沛的雨量可有力促进植被恢复和经济发展,居民贫困化可使石漠化恶化。   相似文献   

2.
西南地区石漠化分布、演变特征及影响因素   总被引:1,自引:0,他引:1  
安国英  周璇  温静  童立强 《现代地质》2016,30(5):1150-1159
根据中国西南岩溶区1999—2008年石漠化遥感调查结果,研究了该区石漠化发生现状和近十年间石漠化在区域、岩性、地貌及区域经济等方面的演变特征,并对发生石漠化的影响因素进行分析。结果显示,石漠化集中分布在滇、黔、桂三省区;石漠化的发生与岩性和地貌密切相关,其中纯碳酸盐岩中石漠化发生率高于杂碳酸盐岩,并随灰岩或碳酸盐岩含量减少而降低,而地形高差相对大的峰丛洼地、峰林洼地石漠化发生率最高,并随地貌相对高差变小而降低。石漠化发生程度与岩性、地貌关系表现多样,纯碳酸盐岩中轻度石漠化比例高于中度和重度石漠化之和的比例,杂碳酸盐岩中中度和重度石漠化之和的比例高于轻度石漠化比例;在峰林洼地、峰林/缓丘平原中轻度石漠化比例高于中度和重度石漠化之和的比例,缓丘台地和丘陵谷地中中度和重度石漠化之和的比例高于轻度石漠化,是岩溶构造演化与人类活动共同制约的结果。从1999年到2008年间,该区石漠化已经呈现转轻趋势,主要表现在总面积减少,石漠化程度减轻;石漠化演变过程中发生在不同岩性和地貌中改善或恶化发生率的变化趋势与上述石漠化的发生规律相似。石漠化还不同程度地影响居民的生活水平,调查显示,严重石漠化县域内石漠化面积与农民人均纯收入、人均生产总值等呈负相关,县域内石漠化面积是影响农民人均纯收入,乃至人均生产总值最重要的因素。因此,石漠化调查结果显示,研究区石漠化呈向好趋势,但是治理难点依然存在。  相似文献   

3.
高分辨率遥感图像是大比例尺石漠化遥感解译工作的重要信息源。文章以云南省鹤庆县为研究区,采用2011年RapidEye多光谱遥感影像,在对灰岩与针叶林—草体混合标准光谱曲线及不同裸岩率亮度值剖面曲线分析的基础上,运用波段比值法和密度分割法,结合野外现场踏勘和地理底图,开展大比例尺石漠化遥感解译,获得如下调查结果:全县石漠化面积为188.82 km2,占全县总面积的8.13%,占岩溶面积的25.48%,其中重度面积有10.31 km2,占石漠化总面积的5.46%,中度面积有42.28 km2,占石漠化总面积的22.39%,轻度面积有136.23 km2,占石漠化总面积的71.15%。野外验证石漠化等级判对率为84%,达到技术规范要求,这表明文章采用的方法可有效运用于大比例尺岩溶石漠化信息的提取。   相似文献   

4.
广西岩溶石漠化演变趋势及影响因素分析   总被引:1,自引:1,他引:0       下载免费PDF全文
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   

5.
南洞流域东部重点区石漠化现状及治理对策   总被引:8,自引:6,他引:2  
为了探讨南洞流域东部重点区石漠化现状及其治理对策,通过遥感数据分析结果并结合地面实地调查验证,对云南南洞流域东部重点区石漠化分布特征、成因、危害及其区域林地生态环境质量状况进行了分析。结果表明,南洞流域东部重点区石漠化面积占岩溶区面积的17.2%,集中分布于大庄盆地西北部,以轻度石漠化为主,轻度、中度、重度石漠化的面积比例约为7∶3∶1,石漠化与水土流失问题突出,岩溶区林地生态环境质量等级以三级、四级为主,占区域总面积的53.77%,整体水平较低,且明显低于区内的非岩溶地区林地。粗放型畜牧和农耕方式是导致区内石漠化形成和加剧的最重要因素。提出休垦弃焚、恢复次生植被、合理开发利用土地资源、优化农林畜牧产业结构,实施林草建设工程、草食畜牧业工程、水利水保设施工程,建立保障制度和监督机制,开展全面的石漠化综合治理对策,以确保区域生态恢复、农林畜牧经济健康发展及南洞地下河流域生态安全和水资源开发利用。   相似文献   

6.
南洞地下河流域南部岩溶石漠化空间分布特征分析   总被引:5,自引:3,他引:2  
基于2013年9月29日GF-1号WFV遥感数据对南洞地下河流域蒙自幅、个旧幅、新安幅和鸣鹫幅进行岩溶石漠化遥感解译,通过归一化植被指数(NDVI)和植被覆盖度(FVC)提取研究区域内石漠化信息,得到其空间分布规律。研究区岩溶石漠化发生率74.55%,属石漠化高发地区,其中中度石漠化最为发育,占全区石漠化的32.63%,重度石漠化最少,占17.59%。基于岩性、高程、坡向和坡度等4个影响因素与岩溶石漠化进行相关性分析,对不同因素中石漠化发生率的变化规律进行分析,结果表明南洞地下河流域南部区域岩溶石漠化在低海拔、缓坡度和纯碳酸盐岩中较为发育,在不同坡向中岩溶石漠化发育程度则较为相似。   相似文献   

7.
为掌握石漠化对岩溶地表土壤碳量的影响,选择粤北英德市岩背镇塘边村岩溶峰丛不同石漠化程度样地进行系统调查,采用单位面积土壤有机碳指标分析石漠化过程对土壤有机碳储量影响。结果表明:(1)极重度石漠化使土壤厚度、地表生物量显著减少,使岩石裸露率显著增加,但在潜在、轻度至中度石漠化中,差异不显著;(2)极重度石漠化土壤有机碳含量显著高于其他石漠化,中度石漠化土壤有机碳高于轻度石漠化,轻度高于潜在,但差异不显著;(3)10-20 cm 土层有机碳含量明显低于表层,岩石裸露及土壤主要在溶蚀缝隙中分布和发育是造成极重度和中度石漠化单位重量土壤有机碳增加的主要原因;(4)中度、轻度和潜在石漠化单位面积土壤有机碳分别是极重度的49.23倍、47.9倍和29.4倍;(5)岩石裸露率是影响岩溶地表生态的最主要因素,它和地表生物量之间存在极显著的负相关,与单位面积土壤有机碳总量呈显著的负相关关系,和土壤厚度也存在显著的负相关关系,此外,岩溶植物的高度适应性可以削弱石漠化的影响。  相似文献   

8.
西南喀斯特地区是我国实施可持续发展战略的重要地区,同时也是生态环境极为脆弱、石漠化集中分布的地区,但有关可持续发展实验区石漠化的内在演化机制研究还较少涉及。以广西恭城县国家可持续发展实验区为例,利用2000年、2005年、2010年、2015年和2021年遥感影像为数据源,采用人机交互解译法进行石漠化信息提取,定量分析了恭城县石漠化的时空演变规律及其成因机制。结果显示,恭城县石漠化主要经历了2000-2005加速恶化、2005-2015年快速改善和2015-2021年缓慢恶化三个阶段,石漠化总面积在88.96~229.55 km2;2000-2005年,恭城县石漠化表现为无石漠化向轻度和中度石漠化转移,2005-2021年呈逆向改善。西岭镇、莲花镇、平安镇是石漠化发生的主要地区,占全县石漠化总面积的55.47%~61.31%。灰岩区发生的石漠化面积为104.03 km2,占石漠化总面积的72.91%;园地内发生的石漠化面积为56.26 km2,占比为38.12%。结果表明:灰岩区强烈的岩溶作用,以及长期种植的单一经济果林...  相似文献   

9.
基于Logistic-CA-Markov模型的石漠化空间变化规律研究   总被引:3,自引:2,他引:1  
为了揭示岩溶地区石漠化发生、发展的一般规律,文章以贵州省六枝特区为例,获取了1990、2000、2010年石漠化数据。利用Logistic-CA-Markov模型探讨石漠化发生的驱动因子及各类型间的转移情况,并在两种情景模式下对研究区2020年石漠化空间分布进行模拟。结果表明:(1)利用Logistic模型回归分析石漠化驱动因子,能够较好的反映其分布状况,CA-Markov耦合模型模拟石漠化空间分布,精度达到理论要求。(2)无石漠化、潜在石漠化、轻度石漠化、中度石漠化演变过程中受人为因素影响大于自然因素,而强度和极强度石漠化则相反。(3)在现有石漠化演化速率情景下,各等级石漠化的演变轨迹为修复与恶化并存模式,最突出的是潜在和轻度石漠化。(4)在喀斯特山地生态产业修复和封山育林结合情景下,石漠化修复与恶化并存的双重轨迹模式改为以修复为主的单一轨迹模式,其中轻度和中度石漠化治理效果最为突出。因此石漠化治理措施重点应针对轻度和中度石漠化分布区,注重协调人地矛盾,防止利用过程中返回式演变。   相似文献   

10.
基于多源、多时相中高分辨率遥感影像与GIS技术,定位监测、定量分析石漠化的演变过程,有助于认识石漠化的演变过程,从而更好地开展石漠化的综合治理。选取典型喀斯特高原峡谷区为例,基于2000年、2005年、2010年和2013年的影像数据,研究石漠化的演变轨迹、方式和速率等。结果发现:14年间,研究区石漠化总面积变化不明显,但石漠化内部类型之间的相互演变非常显著;石漠化演变以持续好转型为主要方式;无石漠化和潜在石漠化在不合理的人为干扰下易恶化,应注重保护;轻度石漠化在治理过程中易反复,应防治结合;中度石漠化在人为干预治理过程中易好转,应作为石漠化治理的核心。在人为干预下,中度石漠化和轻度石漠化的演变速率较快。对喀斯特高原峡谷区的石漠化演变过程进行定量分析,有助于制定同类地貌背景下的石漠化治理决策与调控机制。  相似文献   

11.
依据《岩溶地区水土流失综合治理技术标准》(SL461-2009),以蚂蝗田岩溶小流域为研究对象,实地测量了22组典型地物光谱,发现岩石和土壤在红光-近红外二维光谱特征空间具有线性分布规律,由此推导出土壤—岩石指数方程,并构建了岩溶区土壤侵蚀与石漠化强度分析技术流程。在此基础上,利用研究区RapidEye卫星遥感影像,通过提取土地利用、植被覆盖度、基岩裸露率和坡度等指标因子信息,实现了土壤侵蚀与岩溶石漠化强度的分析评价。研究发现:岩溶区土壤侵蚀与植被覆盖度呈负相关性,与坡度和基岩裸露率无单向相关性;岩溶石漠化与植被覆盖度呈负相关性,与坡度呈正相关性,与基岩裸露率呈线性相关。   相似文献   

12.
The presence and conditions of roadways determine the utilization of natural resources, which exert direct and indirect influences on karst rocky desertification (KRD) in undeveloped karst areas. This paper addresses the relationship between KRD and its distance to roadways in Pingguo County, a typical peak-cluster depression area in Guangxi Zhuang Autonomous Region in Southwest China, focusing on the three time periods of 1994, 2001, and 2009. KRD maps for each time period were interpreted by using remote sensing and GIS technology in buffer zones, which are 4.0 km wide and subdivided into eight strips of 0.5 km wide each. They are located alongside various classes of roadways, namely trunk, town, village, and unpaved roadways. Results demonstrate that slight KRD is the major type in buffer strips on both sides of roadways, which tends to decrease with an increase in distance to road baseline. In contrast, moderate and severe KRD cases cover relatively limited areas, which tend to change less rapidly. Moreover, these two KRD cases are less related to their distance to trunk and town roadways than to village and unpaved roadways. Therefore, the distance to roadways affects slight KRD distribution more than moderate and severe KRD. Temporal KRD patterns indicate that slight, moderate, and severe KRD areas alongside all roadway classes have comparatively similar trends in the periods of 1994, 2001, and 2009 KRD areas alongside various classes of roadways in the three periods (except some of those alongside the town and trunk roads) rank as follows from highest to lowest, 2001, 2009, and 1994. However, the total area in town and trunk roads is relatively small and varies little with distance from strip-to-road. KRD alongside various roadway classes is affected jointly by historical policy, distance to roadways, and landscape.  相似文献   

13.
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   

14.
通过对地形图和Landsat系列影像的目视解译获取冰川边界, 分析得到1971 - 2015年羌塘高原藏色岗日冰川变化。结果表明: 2015年研究区有冰川84条, 总面积(297.65±4.29) km2; 1971 - 2015年冰川持续退缩, 面积减少(19.32±24.31) km2, 年均退缩率为(0.14±0.17)%, 退缩较慢; 五个时段年均退缩速率分别为(0.12±1.46)%、 (0.20±0.32)%、 (0.12±0.50)%、 (0.01±0.57)%和(0.16±0.31)%。消融期(5 - 9月)温度的上升是研究区冰川退缩的主要驱动力。小规模冰川(<0.5 km2)的退缩率14.00%大于大规模冰川(>2 km2)的5.58%; 北朝向冰川的退缩率8.06%大于南朝向冰川的4.16%; 冰川数量由78条增加到84条反映出大冰川在退缩的过程中分裂成小冰川; 2条冰川末端发生前进。  相似文献   

15.
Karst rocky desertification (KRD) is one major type of desertification which is under irrational human impact on the vulnerable eco-geo-environment. In this study, Zhudong fengcong rocky desertification landscape was selected to investigate the land use types distribution law in different rock types and the KRD land in different land use types. KRD data was determined by user–computer interactive interpreting method from Aster images in 2004, according to the exposed ratio of rock, the coverage of vegetation and soil in 0.2 km2 unit, integrating with land utilizing present situation map, hydrogeology map, relief map, vegetation map, soil distribution map, as well as the practical investigation and the population census datum in 2002. Results showed that the occurrence ratio of KRD land is different in land use types and rocky assemblages obviously; land cover has a strong impact upon KRD. The sloping cropland distributed in homogenous limestone has a higher occurrence ratio of light KRD, secondly, is in the limestone interbedded with clastic rock. Light KRD land was dominated by shrubland, and sloping cropland accounts for 11.67% of it, moderate KRD land was dominated by moderate coverage grass slopes, strong and extremely strong KRD was dominated by rocky dry land which is difficult to use.  相似文献   

16.
本文以1974年MSS、1999年TM、2007年TM影像为基本数据源,辅以实地踏勘,考虑一个完整的峰丛洼地等,扣除其平坝部分后作为评价单元,获得了贵州省盘县3个时期的石漠化数据并计算了石漠化和无石漠化土地的演变轨迹。相应于1974年、1999年、2007年3个时段,研究区土地退化演变轨迹可分为8种,并可进一步归纳为不变型、逆转减弱型、反复型和加重型4种演变过程类型,从1974年、1999年到2007年未发生过变化的不变型轨迹面积占较高的比例。研究区的喀斯特土地可分为石漠化土地、无石漠化土地、石漠化已恢复土地和潜在可恢复石漠化土地。  相似文献   

17.
Over the past decades, the vast limestone mountain areas in southwestern China have suffered greatly from karst rocky desertification (KRD), which is a unique type of desertification caused by irrational land-use practices and has drawn increasing attention of international academic community. Characterizing soil erosion in this region is the key to understanding the escalating KRD problem and finding solution to it. The authors applied leveling method to study soil erosion process in the Huajiang Karst Canyon area between 1999 and 2003, and tried to relate it to KRD expansion. The monitoring data indicate that soil in the study area was losing at an alarming rate, which is much higher than soil formation rate and has already resulted in severe KRD problem. Soil loss under different land-use conditions varied greatly during the monitoring period. The highest soil erosion rate occurred in bare and newly abandoned cropland, followed by sparse grass land, forest land, and dense grass land. In addition, soil erosion could be significantly different under different micro-topographic conditions. Because soil erosion rate in the studied karst mountain areas is surprisingly high, it is urgent to take quick actions to fight against the ongoing KRD problems in Southwest China before an irreversible situation occurs. However, the traditional way to combat KRD by abandoning current cropland needs to be carefully reconsidered, since a bare newly abandoned cropland may suffer more from rapid soil loss than before.  相似文献   

18.
文章以桂黔滇喀斯特石漠化防治的国家重点生态功能区贵州区为研究对象,以2010、2015年遥感影像、基础地理信息、降水、土壤等数据资料为基础,集成3S技术和生态评估模型,对水源涵养、土壤侵蚀和石漠化进行定量和定位研究。结果表明:研究区4个亚区的水源涵养功能等级处于“中”、“高”等水平,2015年比2010年的水源涵养指数有所提高;威宁—赫章区、关岭—镇宁区和册亨—望谟区3个亚区的土壤侵蚀模数较大,水土保持功能等级处于“低”等,罗甸—平塘区的土壤侵蚀模数最低,其水土保持功能等级为“中”等;威宁—赫章区2010年中度以上石漠化比重达16.36%,2015年降为8.74%,生态系统健康度从“低”转为“中”;关岭—镇宁2010年和2015年中度以上石漠化比重分别为8.64%和4.49%,生态系统健康度从“中”转化“高”;册亨—望谟和罗甸—平塘的健康度均为“高”,2015年相比2010年均有所提升;4个亚区的石漠化恶化面积所占比重均不到1.00%,石漠化好转区域分别占27.00%、14.10%、10.24%和5.13%,石漠化得到了有效遏制。今后应继续因地制宜,恢复植被和生态系统,巩固和扩大石漠化防治成果。   相似文献   

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