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1.
岩溶地下水系统是西南岩溶石山地区最基本的水系统,而岩溶地下水系统划分则是正确评价、合理开发利用西南石山地区岩溶地下水资源的重要基础。本文首先按西南岩溶水出露条件划分出3620个岩溶地下水系统,其中地下河系统1179个、岩溶泉系统1152个、集中排泄带岩溶地下水系统562个、分散排泄岩溶地下水系统727个,然后按岩溶含水岩组的出露条件将岩溶地下水系统划分为裸露型(2324个)、裸露覆盖型(108个)、覆盖型(275个)、裸露-埋藏型(98个)、埋藏型(88个)五种类型。除分散排泄岩溶地下水系统外,汇水面积大于1000km^2的其它岩溶地下水系统有26个。在地下河系统中,汇水面积大于10km^2而小于500km^2的有1049个,占88.97%,汇水面积小于100km^2的有711个,占总数的60.3%;在岩溶泉系统中,汇水面积小于50km^2的有814个,占总数的70.66%;在集中排泄带岩溶地下水系统中,汇水面积大于100km^2而小于500km^2的有303个,占总数的53.91%。流量统计结果显示,流量大于1000L/s的岩溶地下水系统有286个,占总数的11.2%,流量大于50L/s至小于500L/s之间的有630个,点总数的63.73%。[   相似文献   

2.
根据峰丛洼地区石漠化治理碳汇的现有研究文献,系统总结了峰丛洼地区石漠化治理过程中的碳储量空间格局及其动态过程、不同模式下的碳汇评价与定量化等方面的研究进展与不足,提出了峰丛洼地区二期石漠化治理应关注碳汇稳定性、受气候变化制约等问题,从而优化资源配置的思路;展望了峰丛洼地区二期石漠化治理工程中碳汇研究的趋势:一方面,将土壤分布格局、碳汇耦合机理研究和增加当地经济效益相结合,提高当地农民参与石漠化治理的积极性,推广和发展第一期石漠化治理工程的成果和经验; 另一方面,将遥感技术与石漠化治理碳汇研究相结合,构建更多碳汇估算模型,为二期石漠化治理碳汇定量化服务。  相似文献   

3.
Karst depressions comprise geomorphologically important sources and sinks for sediments and associated pollutants; yet the sedimentology of many depressions is not well understood in the world. In this paper, the 137Cs technique was employed to estimate recent sedimentation rates in a Chinese polygonal karst depression. The results indicate that the sediment deposition rates ranged from 0.91 to 1.97 mm year−1 from 1963 to 2007, and the average sediment deposition rate and specific deposit yield were estimated to be 1.47 mm year−1 and 20 t km−2 year−1, respectively. These results are consistent with the local monitoring data of runoff fields, which confirms the validity of the overall approach. This shows that the soil loss rate is very low in some karst areas of Southwest China. Above all, the approach appears to offer valuable potential to study surface erosion by estimating sediment deposition rates of karst depressions, rather than the assessment of complicated soil erosion in stony soils of carbonate rock slopes. In addition, the space distribution of surface soil and 137Cs inventories are affected remarkably by the inhomogeneous dissolution of limestone under the soil. It may be an important phenomenon, which exists widely in karst areas, and it is significantly different from other places.  相似文献   

4.
中国西南岩溶关键带结构与物质循环特征   总被引:1,自引:0,他引:1  
岩溶关键带调查研究的目标是揭示岩溶生态系统的动态平衡和演化机制,旨在为经济社会提供资源环境服务的可持续管理对策,指出在合理的人为活动下增强岩溶关键带韧性的办法及修复受损部位的有效途径。碳酸盐岩作为可溶岩,赋予了岩溶关键带在结构上及物质循环过程中的岩石圈-生物圈相互作用等方面的若干特殊性。该文以中国西南岩溶区为例,总结了诸多学者的研究成果,揭示了从桂林岩溶区到重庆武隆岩溶区,岩溶关键带发育厚度由几米逐渐增厚至1 000 m的区域差异; 岩溶关键带的垂向物质循环过程以土壤-表层岩溶带为中心环节,而在横向上则呈现“岛屿状”镶嵌分布特征,地表生态具脆弱性; 岩溶关键带碳循环过程包括岩溶碳循环和生态碳循环两部分,碳汇则由植物碳汇、土壤碳汇和岩溶碳汇组成,初步估算其碳汇通量为64.36 t/(km2·a)。  相似文献   

5.
西南岩溶区高品位旅游资源丰富且种类齐全,但其独特的岩溶地质环境对旅游开发建设、旅游接待经营响应十分敏感。本文立足于“人地共生”的生态旅游理念,以污染、风险、干扰、垄断四大指标为依据,选取了12项评价因子和5项修正指数,构建出PRIM标靶评价模型。通过该模型可计算出生态旅游指数进而定量化评价岩溶区旅游开发项目的生态旅游开发态势;还可根据四大指标在标靶模型中的收敛程度和极轴分布,判定评价目标所存在的主要问题及应采取的相应措施。笔者结合路南石林、桂林漓江和福建天鹅洞三个案例,对PRIM标靶评价模型进行验证,评价结果显示,路南石林、桂林漓江生态旅游指数稳定,属于标准的生态旅游景区,但垄断指标较高,后期需要调整旅游收入再分配比例;福建天鹅洞属于准生态旅游景区,在旅游安全措施、开发垄断等方面还存在不足,需要进一步完善。   相似文献   

6.
我国水土保持和石漠化防治是以小流域为单元来开展工作的,而在喀斯特地区进行小流域划分的研究还比较少。以1∶5万地形图作为工作底图,进行数字化采集并结合空间插值的方法生成贵州省金沙县DEM数据,并以GIS的水文分析模块为基础,经过自动提取微流域,微流域归并,流域边界验证等过程,最终提取金沙县小流域338个。从提取的结果来看,小流域的面积集中分布在3~10 km2范围内,占小流域总数的79.29%;在完整型、区间型和坡面型三种小流域类型中,研究区小流域类型以完整型小流域为主;绝大部分流域的分界线能够达到要求,在峰林、峰丛、洼地分布的地方会出现分界线偏离山顶点或者鞍部,这些地方水系网络复杂,自动提取的小流域与实际不相符合,需要进行手动修改。   相似文献   

7.
刘斯文  储国强  赖忠平 《地质学报》2016,90(8):2013-2022
巴丹吉林沙漠发育了世界上独一无二的丘间湖泊群,100多个永久性的丘间湖泊分布于沙漠的东南部。沙漠湖泊岩芯是干旱地区重要的气候、环境档案,然而受沙漠湖泊发育极端环境的影响,岩芯测年面临很大挑战。本文选择巴丹吉林的沙漠南缘的阿尔吉林和敦德吉林进行钻探,获取无扰动岩芯,利用核素(210Pb、137Cs)进行测年,并计算其沉积速率。结果表明:(1)核素(210Pb和137Cs)测年能够获取巴丹吉林沙漠丘间现代湖泊岩芯的可靠年代。(2)岩芯Ar-1的CRS测年结果为102±8a,沉积速率分布范围为0.13 ~ 0.33cma-1,岩芯Dd-1的CRS测年结果为123±2a,沉积速率分布范围为0.18 ~ 0.70cma-1。(3)沙漠岩心沉积速率空间分布具有自沙漠腹地向边缘递增的趋势,210Pbuns-CRS平均沉积速率分布范围为 0.16 ~ 0.57cma-1 ,137Cs沉积速率分布范围为0.05 ~ 0.6 cm a-1。未来对于沉积速率空间变化的可能影响因素,如高大沙山的围限阻挡效应、137Cs的分子扩散效应以及古地震等,应进行更深入研究。  相似文献   

8.
为探讨黔南平塘县及周边喀斯特峰丛洼地石漠化生态治理与农户生计模式,在分析区内水土资源及其空间匹配结构特征,以及石漠化与生态景观垂直分异规律的基础上,提出了:(1)峰丛洼地生物多样性藤冠配置技术模式,包含轻度石漠化藤本+乔木模式、中度石漠化藤本+灌木模式、重度石漠化藤本+草本模式;(2)峰丛坡地“下修复、上保育”的分段治理(垂直分异)模式及其技术体系,包含峰顶生态公益林自然恢复(保育)模式、峰丛中上坡生态经济型林草生态修复与混农林业模式、峰丛下坡高效复合农林经营与水土保持(生态修复)模式;(3)筛选出酥李、西番莲、土人参、旱脆王枣、欧李等耐瘠耐旱适生品种,并对这些品种及其组合模式的经济、社会与生态效益进行了初步分析,得到西番莲+冰脆酥李、西番莲+土人参、西番莲+酥李+土人参等生物多样性配置模式的经济效益最佳,其是就地解决洼地农户生计的有效途径,这在类似地区有重要的推广和应用价值。  相似文献   

9.
武毅  孙银行  李凤哲 《中国岩溶》2011,30(3):278-284
针对西南岩溶地区表层带岩溶水、管道型岩溶水(溶洞、暗河、管道等)、构造裂隙岩溶水等不同类型地下水赋存介质特点,通过适宜的地球物理方法使用条件以及找水特点的分析,提出不同含水介质中寻找地下水地球物理勘查要解决的地质问题、拟采用的综合物探方法,分别总结出了它们的电性参数(或曲线)的响应特征,形成了不同含水介质的地球物理勘查技术组合方案。最后通过实例验证其实用性,并对在西南岩溶地区地下水地球物理勘查工作中积累的技术经验进行了总结。   相似文献   

10.
西南喀斯特山地水土流失特点及有关石漠化的几个科学问题   总被引:34,自引:4,他引:34  
由于特殊的岩土组构,喀斯特坡地的水土流失具有如下特点:地表和地下流失相互叠加;地表产流、产沙少;纯碳酸盐岩区地下流失比例大。论文区别了石漠化和石质化的科学内涵,指出了喀斯特山地石漠化的核心是土地的石质化,提出了按照地面物质组成与裸岩率叠加的石漠化分类系统。根据土壤中硅酸盐矿物的物质平衡,提出了不同碎屑岩含量碳酸盐岩区的土壤允许流失量介于5~500 t/(km2?a)之间。喀斯特坡地土壤虽然肥沃,但总量太少,矿质养分不足可能是石质坡地植物生产力低的重要原因。此外,根据农耕驱动土地石质化的机制,提出了相应的石漠化治理的对策建议,具体是:(1)不但要治标,提高植被覆盖率,更要治本,防止或减缓土地石质化,同时还要增加群众收入;(2)按照坡地岩土组成的垂直分带特点,因地(土)制宜,开展治理;(3)重视矿质肥料的施用;(4)在纯碳酸盐岩土石质和石质坡地农田的小型蓄水工程修建中,要加强集流面建设。   相似文献   

11.
Through utilizing water flow monitoring, rock scratching, soil wood piles and radionuclide 137Cs tracing in the Longhe karst ecological experimental site (hereinafter referred to“Longhe site”), Pingguo County, Guangxi Province, the features and values of soil erosion and soil leakage in different geomorphologic locations and land uses in the karst peak-cluster depressions are showed clearly. There are four kinds of geomorphologic locations in the karst peak-cluster depression, namely peaks, strip, slopes and depression. The soil leakage modulus in the peaks and strips respectively occupy 92.43% and 96.24% of the total mean soil erosion modulus at experimental sites. On the slope, soil leakage accounted for about 75%. At the bottom of depression, surface water was the main factor of soil erosion, and at last most soil leaked into underground rivers from sinkholes. The total soil erosion modulus and the contribution rates of relative surface soil erosion in regard of peaks, slopes and depressions gradually increased. There are also five major types of land use in the karst peak-cluster depressions, farmland, Kudingcha tea plantations, young Lignum Sappan fields, shrub-grassland and pastures. The soil erosion modulus of slope farmland has the highest value with an increasing trend year by year. But soil erosion modulus of other four land use types decreased by year, which shows the “grain for green” will result in better soil protection. By handling with rocky desertification and ecological rehabilitation in Longhe site, the mean soil erosion modulus of the karst peak-cluster depression has decreased about 80% from 2003 to 2015.  相似文献   

12.
The direction and intensity of karst processes can be deeply affected by soil physical and chemical variations which were resulted from land use. Taking Nongla Fengcong depression area, Mashan County, Guangxi as an example, authors discussed the impact of land use on karst processes based on the data of field limestone tablet. The results showed that the corrosional rates at varied soil depth are quite different. Corrosional rate in woodland and orchard is mostly bigger than 20 mg/a, which is much higher than that in tilled land and shrub. Generally, corrosional rate decreased from orchard, woodland, tilled land, fallow land and shrub successively, in which soil organic matter (OM) and soil pH are two major controlling factors: corrosion process is controlled remarkably by soil OM in woodland and orchard. The higher the organic matter content is and the less the pH value is, the higher the corrosional rate is. Owing to lower organic matter content, the corrosional rate is mainly affected by soil CO2 in tilled land and shrub.  相似文献   

13.
It is necessary to understand the aquatic chemical characterstics of natural surface fresh water for water quality assessment.The chemical data from different kinds of water in the central Guizhou karst area showd that spring water from carbonate rock cracks(crack-water)is of neutrality or meta-alkalinity and [C] Ca II type.The amounts of all ions and the concentrations of HCO3^- and Ca^2 were higher in the autumn than in the spring,The crack-water was influenced by the infiltration of surface water in the process of erosion and /or trans-portation with decreasing HCO3 and increasing pH,SO4^2-,Cl^-,K^ and Na^ during running in a certain distance on the land surface .In particular,the chemical compositions of the waters at Tianxingqiao(upper-stream),Shuiliandong(mid-waterfall)and Luoshuitan(down-pool)near the Huangguoshu Waterfall were much different from those of the crack-water.The concentration of SO4^2-,Na^ ,Fe^3 and NO3^- varied closely with seasons.The CaCO3 deposited violently with CO2 release in the spring ,In Lake Hongfeng the HCO3^-/SO4^2- equivalent ratios were only 2.1-2.4 ,but Ca^2 /Mg^2 up to 2.4-4.2.The Cl^- concentration increased by a factor of 1 and Na^ by order of magnitude relative to the spring water.These indicated the increase in artificial pollutant discharge in the Lake Hongfeng watershed.In addition,Proewater in the soils covering carbonate rocks belongs to strongly mineralized water,The obvious differences in water quality were controlled by carbonate deposition,sulphate mineralization and nitrogen fixation as well as ammonification.It is indicated thaty the chemical compositions in the waters from the karst region were unstable and changeable.  相似文献   

14.
以贵州龙里典型喀斯特地区为例,通过集成RS/GIS技术,利用生态水文评估工具中模块化生态水文综合管理系统(EcoHAT)对研究区绿水资源进行定量模拟,模拟出该区2005年10月-2006年10月像元尺度上绿水资源量,并分析了其绿水资源消耗效用.结果表明:研究区林地、草地、灌丛和农用地单位面积土壤蓄变量月均值分别为5.6mm、6.3 mm、6.9 mm、7.7 mm;林地、草地、灌丛和农用地绿水资源单位面积年有效消耗量分别为:423.0mm、344.2 mm、386.7 mm、407.5 mm,其中低消耗量分别为相应植被类型条件下总有效消耗量的47.0%、48.3%、52.7%、61.3%.在有效消耗量中,农用地低消耗量占较大比重,林地和草地的高效和低效消耗量相近,但草地的低消耗量大于林地.据此,认为贵州龙里典型喀斯特地区绿水资源具有较大的利用潜力.但是在今后的绿水资源利用中,必须加强调控绿水资源消耗效用,增加植被盖度,减少裸地面积,以减少绿水资源的无效消耗量;与此同时,还应调整植被结构,以减少植被棵间土壤的低效消耗量.  相似文献   

15.
贵州茂兰峰丛草地洼地小流域侵蚀产沙的137Cs法研究   总被引:1,自引:1,他引:1  
在贵州茂兰峰丛洼地区的工程碑草地洼地典型小流域进行了洼地沉积泥沙^137Cs示踪分析研究。研究结果表明:(1)草地洼地土壤剖面属于堆积土壤剖面,土壤剖面中^137Cs浓度分布特征反映了泥沙堆积与表层土壤侵蚀的信息。受岩土分布、微地形的影响,^137Cs初始沉降后出现不均匀再分布,面积活度的空间变化较大,变异系数为1.35,不能表征土壤侵蚀状况。(2)根据草地洼地典型堆积农耕地土壤剖面A-1的^137Cs浓度分布特征,1963年以来的流域平均堆积泥沙数量是16.6t/km^2.a,流域平均土壤侵蚀速率为45.95t/km^2.a,约占侵蚀产沙数量63.88%的泥沙以地下流失的形式散失;(3)草地洼地小流域内地面土壤流失与地下土壤流失的相对贡献率分别是70.13%和29.87%;(4)以茂兰地区最大成土速率为依据推算出的允许土壤侵蚀量是13.51t/km^2.a,草地洼地的土壤侵蚀危险程度极高。  相似文献   

16.
Xiaojiang watershed is a typical karst agricultural region of Yunan Province, China. A case study of land-use changes documents changes of soil properties from 1982 to 2003. The results are as follows: (1) The total land use transformed covers 610.12 km2, of which land use changed from unused land into cultivated land and forestland, and forestland into cultivated land during the past 20 years in Xiaojiang watershed. (2) The rapid growth of population and economic development were the main driving forces of cultivated land increase. (3) Soil properties showed modification owing to different land-use changes. The contents of the soil organic matter, total nitrogen, and total phosphorus in 2003 were significantly lower than that in 1982 after the forestland and unused land were transformed into the cultivated land, but the soil pH increased significantly in 2003. Organic matter, total nitrogen, and total phosphorus for shorter-time reforestation land declined, but the pH increased. Soil properties have improved significantly after cropland was transformed into orchard land. The organic matter, total nitrogen, total phosphorus, available nitrogen, and available phosphorus declined significantly, but pH increased significantly after rock desertification.  相似文献   

17.
广西平果县果化生态重建示范区面积600hm^2,为典型岩溶峰丛洼地,居民贫困、石漠化严重。2001年以来,通过详细调查研究,因地制宜建立了适合峰丛洼地地貌结构特点的复合型立体生态农业模式:开发20多种乡土树种,人工诱导封山育林310hm^2,开发表层岩溶泉、岩溶天窗和隐伏岩溶管道水资源每年1万多立方米,引进了多种优质高效果树和药材,培植了生态产业,在土地整理的基础上,采用综合措施对岩溶土壤进行了改良,在开发引进多种适宜优质牧草的基础上发展家庭养殖业,提高了生态和农业生产的效果和效率,不但石漠化得到治理,峰丛洼地生态逐步恢复,而且农民纯收入年均增加20%,促进了区域经济的发展。   相似文献   

18.
谭庄—沈丘凹陷位于华北克拉通南部,大别山北缘与华北克拉通接壤部位的周口坳陷内。区内下白垩统地层厚度巨大,沉积和沉降中心偏于盆地南侧。沉积物以细粒陆源碎屑砂岩、粉砂岩和泥岩为主;岩石中富含火山碎屑,成分成熟度和结构成熟度中等;发育一系列牵引流成因的沉积构造,属于与河流三角洲——滨浅湖沉积体系及其沉积相的组合,早白垩世沉积物源供给主要来自南部。盆地的发育和演化及早白垩世沉积主要受南部边界的叶鲁断裂控制,属于张性正断层,后期该断层发生明显地向盆地方向的逆冲。依据下白垩统砂岩组分构造属性、砂岩岩屑组分、沉积物常量元素和稀土元素地球化学特征分析以及与南部大别山造山带火山岩发育年代的对比等综合分析认为,谭庄—沈丘凹陷形成于早白垩世伸展大地构造背景,是受大别山北缘山盆耦合作用影响形成的断陷型沉积盆地。  相似文献   

19.
华北东部深部岩溶及煤矿岩溶水害特征   总被引:1,自引:0,他引:1  
针对我国华北东部煤矿井开采深度迅速增加,矿井岩溶水害日益加重的客观问题,文章分析讨论了深矿井开采的基本概念,通过统计分析,得出中国东部主要煤矿井目前开采深度达到600 m左右且以12 m/a左右的速度向深部延伸的变化趋势。从华北东部地区沉积古地理环境与地壳运动演化史方面分析了该地区厚层奥陶纪灰岩的形成及其后期岩溶发育过程。通过对研究区几个重点矿区揭露的奥陶系灰岩岩溶发育特征在穿层和顺层方向上随深度变化规律的分析,揭示出华北东部主要煤矿区奥陶系灰岩岩溶发育特征在垂向上具有弱-强-弱和顺层方向上随埋深具有由强到弱的变化规律。提出了华北东部煤矿深部开采将面临的岩溶水害问题及其防治水技术思路。  相似文献   

20.
西南岩溶地下水资源开发利用效应与潜力分析   总被引:20,自引:0,他引:20  
西南岩溶地区面积78万km2,地下水系统包括裸露岩溶水系统和覆盖-埋藏型岩溶水系统两大类。由于降水丰富、地下岩溶发育,西南岩溶地下水资源丰富,在43万km2调查区内,具有地下水天然资源量1762.82×108m3/a,岩溶地下水允许开采资源量615.70×108m3/a。近年来,通过开展水文地质调查,在地下河、表层岩溶水和蓄水构造岩溶水打井开采方面均取得重要进展,产生了显著的经济和生态环境效应。但由于西南地区岩溶水开发难度大,区域经济落后,西南岩溶地下水的开发利用程度普遍较低,已开采量为98.32×108m3/a,仅占允许开采量的15.97%,剩余地下水潜力资源量517.38×108m3/a。  相似文献   

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