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水库消落带对旅游业的影响及对策研究——以三峡水库为例 总被引：1，自引：0，他引：1
水库消落带的研究传统上主要集中于库区生态环境变化和常规经济利用方面.我国大型水利水电工程建设形成的消落带的重要的利用方式就是旅游业的开发,但是关于水库消落带对旅游业可能产生的潜在与长期的影响目前尚未引起研究者的充分重视.以中国面积与涨落幅度最大的消落带--三峡水库消落带为研究对象,分析了三峡水库消落带对三峡旅游的景观、环境、旅游生产与管理等方面可能产生的负面影响,同时也说明其可能带来一定的利用机遇,强调三峡库区在旅游业的发展中要积极规避消落带带来的负面影响,并合理对消落带土地进行旅游利用. 相似文献
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[目的]三峡水库蓄水运行后消落带生境破碎斑块化加剧,极端生境胁迫严重损害植被的结构和功能。厘清三峡水库消落带生境状况,提出适宜性植被恢复对策,重建河流受损廊道综合生态功能,对构建区域生态安全格局和保障长江流域水资源安全具有重要意义。[方法]针对三峡水库消落带植被退化与生态功能受损的突出问题,系统解析了消落带生境特征及其对植被生长的影响,围绕水库河岸受损廊道生态修复重大需求,探讨面向消落带微生境构建与植被格局功能优化的三峡水库消落带植被恢复模式。[结果]三峡水库消落带生境状况受水库运行形成的独特水位节律、出露期植被生长季气候条件、土壤侵蚀与泥沙沉积过程、土壤环境等多生境因子协同影响,呈现高度空间异质性特征。水位变动形成的淹没时长、出露时令、淹水强度是影响植株繁衍、生长的首要因素;土壤侵蚀、泥沙掩埋、土壤水养条件等影响植被生长状况。[结论]三峡水库消落带植被恢复需综合考虑水位节律、立地条件与物种形态-功能性状,选育优质抗逆物种,注重土壤基质保育,突出植被格局的分区优化配置。重建消落带综合生态功能,为水库消落带生态治理提供理论支撑和科学依据。 相似文献
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金沙江干热河谷水电站库区消落带生态修复对策研究 总被引：1，自引：0，他引：1
通过对水库运行后消落带的特点进行分析,预测了金沙江干热河谷水电站水库建成后,由于水库水位的涨落形成的消落带,可能会带来环境污染、土壤侵蚀和水土流失、生态系统被破坏、诱发地质灾害等生态环境问题。通过实地调查、现场试验和对三峡等消落带的分析研究,确立了电站水库蓄水后消落带应该具备的立地类型和消落带区域在水库建设过程中应相配套的工程措施;以及在水库蓄水后水面以下0～5m应种植杨柳等高大乔木;5～15m应种植根系发达的草本,如香根草等;15～30m应以苏丹草、稗草、小米草等饲草为主。 相似文献
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根系吸水的最小能量模型的实验验证与评价 总被引：13，自引：0，他引：13
三峡水库是我国特大型水利枢纽工程.三峡工程建成后,随水库运行将在厍区两岸形成垂直落差30 m的消落带,面积达300 km2.结合三峡库区消落带的气候、坡度、水深、地貌等区域基本特征,以遥感数据为基础,以GIS技术为手段,对三峡库区消落带土地资源进行分析研究,划分出消落带土地资源的6种类型,即硬岩型消落带、软岩型消落带、松软堆积型消落带、库尾松软堆积型消落带、湖盆松软堆积型消落带、岛屿松软堆积型消落带,并给出了不同类型消落带的可持续土地资源利用模式. 相似文献
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三峡水库消落带土壤侵蚀问题初步探讨 总被引：7，自引：2，他引：7
三峡水库蓄水运行后将出现一个落差达30 m的消落带,由于库水涨落和水文地质条件改变,导致沿岸植被破坏,地表裸露,在降水、库水位周期性地涨落和涌浪的作用下,土壤侵蚀强烈,对当地的经济及环境产生影响,故对消落带的土壤侵蚀问题应予以重视。根据三峡水库2007-2010年试验性蓄水产生的消落带实地调查,在总结消落带土壤侵蚀主要影响因素的基础上,分析了三峡水库消落带几种典型的土壤侵蚀形式:波浪侵蚀、降雨径流侵蚀、崩塌及滑坡,其中波浪侵蚀和崩塌最为突出,其次为消落带成陆期的降雨溅蚀和径流冲刷,而滑坡主要以蠕滑和前缘崩塌为主。同时,针对岸坡的不同物质构成和地形地貌,提出了不同土壤侵蚀类型的主要分布特点,可以给库区消落带土壤侵蚀的防治提供借鉴。 相似文献
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随着大型水利工程的兴建,水库生态环境正在不断恶化。水位的周期性变化使消落带生态脆弱性增强、水土流失加剧、地质灾难增加、岸边污染加重,并可能诱发流行病疫情,原有消落带生态系统遭到较为严重的破坏。本文在阐述消落带的分类后,通过分析周期性淹水对消落带的影响,探讨了水库蓄水运行后可能产生的生态环境问题,并提出了有效的防治对策,以期建立可持续发展的消落带生态系统。 相似文献
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贵州红枫湖水库消落带类型划分及其生态修复试验 总被引：1，自引：0，他引：1
水库消落带是防止水体污染的最后一道生态屏障,恢复或重建消落带植被是水库水质管理的一项重要措施,也是当前水库水体污染控制的研究热点和难点问题之一。消落带类型划分可为消落带分区规划治理提供指导。根据喀斯特山区水库消落带自然结构的质地和坡度,将红枫湖水库消落带分为河口型消落带、库湾滩地消落带、土质缓坡消落带、砾质坡地消落带和岩质岸坡消落带5种类型,对各种类型的消落带特征进行了分析,并提出了红枫湖水库消落带生态恢复的设计原则与工程模式。红枫湖水库消落带生态修复试验表明,恢复与重建后的消落带系统生物多样性增加、生态功能增强。 相似文献
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三峡水库库岸地质灾害防治之我见 总被引：1，自引：0，他引：1
三峡库区是地质灾害频发区,水库蓄水运行降低两岸坡地稳定性,使滑坡、崩塌等地质灾害活动增加.蓄水后的地质灾害活动变化可分为:(1)加剧期;(2)强烈期;(3)减弱期;(4)"准稳定态"期.地质灾害的危害性不仅和灾害体的规模、位置和活动方式有关,还和受灾对象的重要性、受害方式和修复的难易有关,大型滑坡、崩塌产生的次生涌浪灾害也是三峡水库地质灾害重要的成灾方式.根据三峡水库面山地带地质灾害的发展趋势,灾害特点和受灾对象的重要性,考虑到对地质灾害认知的不确定性,结合当地的区域社会经济发展水平,提出了"因‘物'制宜,避让为主,治理为辅"的防治方针和相应的对策建议. 相似文献
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M. S. Kuznetsov V. V. Demidov D. R. Abdulkhanova 《Moscow University Soil Science Bulletin》2009,64(1):33-37
The distribution of differently eroded soddy-podzolic soils on slopes of different gradients, lengths, and aspects has been studied with the use of a quantitative parameter of slope erodibility K. The latter is calculated as a product of slope gradient in the power of 1.3 and the length of the flow line (m) in the power of 0.5. It is shown that moderately eroded soddy-podzolic soils appear on the slopes of northern and northeastern aspects with K equal to 0.4; on the slopes of southern aspect, this parameter is somewhat lower (0.24). Moderately eroded soils prevail on the slopes of northern and northeastern aspects with K equal to 0.7. 相似文献
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Determining how soil erosion affects enzyme activity may enhance our understanding of soil degradation on eroded agricultural landscapes. This study assessed the changes in enzyme activity with slope position and erosion type by selecting water and tillage erosion-dominated slopes and performing analyses using the 137Cs technique. The 137Cs data revealed that soil loss occurred in the upper section of the two eroded slope types, while soil accumulation occurred in the lower section. The invertase activity increased downslope and exhibited a pattern similar to the 137Cs data. The spatial patterns of urease and alkaline phosphatase activities were similar to the 137Cs inventories on the water and tillage erosion-dominated slopes, respectively. On both the eroded slope types, the invertase activity and soil organic carbon content were correlated, but no correlation was observed between the alkaline phosphatase activity and total phosphorus content. Nevertheless, the urease activity was correlated with the total nitrogen content only on the water erosion-dominated slopes. The enzyme activity-to-microbial biomass carbon ratios indicated high activities of invertase and urease but low activity of phosphatase on the water erosion-dominated slopes compared with the tillage erosion-dominated slopes. Both the invertase activity and the invertase activity-to-microbial biomass carbon ratio varied with the slope position. Changes in the urease activity-to-microbial biomass carbon ratio were significantly affected by the erosion type. These suggested that the dynamics of the invertase activity were linked to soil redistribution on the two eroded slope types, whereas the dynamics of the urease and alkaline phosphatase activities were associated with soil redistribution only on the water or tillage erosion-dominated slopes, respectively. The erosion type had an obvious effect on the activities of invertase, urease and alkaline phosphatase. Soil redistribution might influence the involvement of urease in the N cycle and alkaline phosphatase in the P cycle. Thus, enzyme activity-to-microbial biomass ratios may be used to better evaluate microbiological activity in eroded soils. 相似文献
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Temporal changes of eroded soils depending on their agricultural use in the southern Cis-Ural region
I. M. Gabbasova R. R. Suleimanov I. K. Khabirov M. A. Komissarov M. Fruehauf P. Liebelt T. T. Garipov L. V. Sidorova F. Kh. Khaziev 《Eurasian Soil Science》2016,49(10):1204-1210
Temporal changes of eroded soils in the southern Cis-Ural region (Republic of Bashkortostan) depending on their agricultural use during the period from 1975 to 2011 were studied. In the northern foreststeppe zone, the development of erosion processes was retarded upon the use of soil-saving management practices and grain-fallow-grass crop rotations. In slightly eroded light gray forest soils (Eutric Retisols (Cutanic)), the thickness of humus-accumulative horizons and the content of humus increased; the conversion of cropland into permanent fallow was found to be the most efficient measure to control soil erosion. In podzolized chernozems (Luvic Greyzemic Chernic Phaeozems) and typical chernozems (Haplic Chernozems) of the Cis-Ural steppe, the content of humus in the plow layer under grain-row crop rotation and classical soil management decreased, especially in moderately eroded soils. The development of water and wind erosion on slopes depended on the slope shape: the texture of soils at different degrees of erosion on slopes with free runoff became coarser by one gradation after 35 years; in the presence of linear obstacles in the lower part of slopes, the content of fine fractions in moderately and strongly eroded soils increased. 相似文献
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A. D. Thomas R. P. D. Walsh R. A. Shakesby 《Land Degradation \u0026amp; Development》2000,11(3):257-271
The impact of different logging techniques on nutrient losses in burnt eucalyptus and pine forests in northern Portugal was investigated. A variety of logging techniques is used in the region resulting in varying amounts of slash debris on the slopes. The efficacy of this litter in reducing soil erosion is well established but less is known about the impact on nutrient losses. Small bounded plots were used to examine the impact of varying amounts of slash debris and pine‐needle cover on nutrient losses in overland flow and adsorbed to eroded sediment over 19 months during the first two–three years after fire. Nutrient losses in solution and adsorbed to eroded sediment were substantially higher on burnt terrain due to increased erosion and overland flow generation and high nutrient concentrations at the soil surface in the burned forests. Post‐fire logging techniques in eucalyptus forests resulting in large amounts of litter debris on the slopes are effective at reducing eroded sediment nutrient losses but less effective at reducing losses in solution. In pine forests, litter is largely ineffective in reducing solute and sediment nutrient losses. However, a covering of pine needles was shown to be highly effective in reducing eroded sediment nutrient losses and to a lesser extent solute losses. Conservational methods of logging are suggested for both eucalyptus and pine forests in the region. In the absence of such measures, the sustainability of short‐rotation eucalyptus forestry is questioned in northern Portugal. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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E. M. BRIDGES 《European Journal of Soil Science》1969,20(2):236-245
The investigation attempts to ascertain rates and amounts of soil erosion from a small unvegetated area (120m×15m). Measurements from markers embedded in the soil indicate a removal of 10 mm per annum on 5°C slopes, 32 mm per annum on 45°C slopes, and 43 mm per annum on 62°C slopes. A sediment trap indicated that in a week when there was 56·8 mm rain, approximately 60 g/sq m was eroded. Results of the work are used in an explanation of the eroded soils of a much larger area, known as the Lower Swansea Valley. 相似文献
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黄土丘陵沟壑区坡面径流侵蚀试验研究 总被引：15，自引：0，他引：15
黄土丘陵沟壑区的水土流失主要由汛期一两次中大强侵蚀性暴雨引起。采用径流侵蚀模拟试验的结果表明,在农地、林地、草地、荒坡条件下,侵蚀率随时间的增加而逐渐减少;径流冲刷侵蚀量在坡度10°～26°之间是随着坡度的增加而增大的,坡度大于26°后趋于减小;径流侵蚀量随坡长的增加而增大。 相似文献
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喀斯特坡地表层岩溶带发育，入渗强烈，产流机制与非喀斯特坡地有较大差异，为提高喀斯特坡地土壤流失模型预测准确性，以贵州省普定县陈旗小流域6个不同土地利用类型径流小区为观测对象，分析2007—2010年、2015—2019年2期泥沙和地表径流数据，了解产流产沙规律，并利用降雨侵蚀力偏差法计算各小区侵蚀性降雨量。结果表明：(1)植被覆盖率与喀斯特坡地地表产流产沙量呈负相关，高植被覆盖下，暴雨和极端暴雨是造成喀斯特坡地水土流失的主要降雨事件；(2)植被恢复十余年随着覆盖度的提高，年均土壤流失量呈显著下降趋势，多小于10 t/km2;(3)喀斯特坡地裂隙发育，地下漏失严重，土壤量少且不易被侵蚀，除少数极端暴雨外，多数降雨不产流不产沙，因此建议将喀斯特坡地侵蚀性降雨量阈值定为50 mm,该阈值显著高于非喀斯特地区。 相似文献
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The long-term effect of tillage on soil displacement of hilly areas used for growing wheat in Greece 总被引：1，自引：0，他引：1
Abstract. Tillage displaces large amounts of soil from upper slopes and deposits soil in lower landscape positions, greatly affecting productivity in these areas. The long-term effect of tillage on soil erosion was studied in four field sites growing mainly rainfed wheat. The soil loss from landscape positions with slopes, ranging from 3 to 28%, was estimated by: (a) comparing data of horizon thickness described at the same position at different times; and (b) using soil movement tracers added to the soil. Existing empirical relationships were used for estimating soil loss by tillage and runoff water, and loss in wheat biomass production. The experimental data showed soil losses of 0.4 to 1.4 cm yr–1 depending on slope gradient, plough depth, and tillage direction. In two of the sites, soil depth has been reduced by 24–30 cm in a period of 63 years. The mean soil displacement of the plough layer (30 cm thick), measured by soil movement tracers, ranged from 31 to 95 cm yr–1 depending mainly on slope gradient, corresponding to a rate of soil loss of 0.3 cm to 1.4 cm yr–1 . Soil eroded from the upper slopes was deposited on the lower slopes increasing soil thickness by 0.4 cm to 1.4 cm yr–1 . The application of empirical relationships, estimating soil loss by tillage and water runoff, showed that soil erosion at the field sites can be mainly attributed to tillage. The loss in wheat biomass production due to erosion was estimated at 26% on upper slopes for a period of 63 years, while a 14.5% increase in wheat production was estimated due to deposition of soil material in the lower landscape. 相似文献
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Accelerated soil erosion can impact upon agronomic productivity by reducing topsoil depth (TSD), decreasing plant available water capacity and creating nutrient imbalance in soil and within plant. Research information on soil‐specific cause – effect relationship is needed to develop management strategies for restoring productivity of eroded soils. Therefore, two field experiments were established on Alfisols in central Ohio to quantify erosion‐induced changes in soil properties and assess their effects on corn growth and yield. Experiment 1 involved studying the effects of past erosion on soil properties and corn yield on field runoff plots where soil was severely eroded and comparing it with that on adjacent slightly eroded soil. In addition, soil properties and corn grain yield in runoff plots were compared on side‐slopes with that on toe‐slopes or depositional sites. Experiment 2 involved relating corn growth and yield to topsoil depth on a sloping land. With recommended rates of fertilizer application, corn grain yield did not differ among erosional phases. Fertilizer application masked the adverse effects of erosion on corn yield. Corn grain yield on depositional sites was about 50 per cent more than that on side‐slope position. Corn plants on the side‐slope positions exhibited symptoms of nutrient deficiency, and the ear leaves contained significantly lower concentrations of P and Mg and higher concentrations of Mn and K than those grown on depositional sites. Corn grain yield in experiment 2 was positively correlated with the TSD. Soil in the depositional site contained significantly more sand and silt and less clay than that on the side‐slope position. There were also differences in soil properties among erosional phases. The soil organic carbon (SOC) content was 19\7 g kg−1 in slightly eroded compared with 15\1 g kg−1 in severely eroded sites. Aggregate stability and the mean weight diameter (MWD) were also significantly more in slightly eroded than severely eroded soils. Adverse effects of severe erosion on soil quality were related to reduction in soil water retention, and decrease in soil concentration of N and P, and increase in those of K, Ca and Mg. Severe erosion increased leaf nutrient contents of K, Mn and Fe and decreased those of Ca and Mg. Corn grain yield was positively correlated with aggregation, silt and soil N contents. It was also negatively correlated with leaf content of Fe. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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R. Lal 《Geoderma》1976,16(5):403-417
Nutrient element losses in runoff and eroded sediments were monitored during 1972 on different slopes and under different soil and crop management treatments. The experiments were conducted on 25 × 4 m field runoff plots, established on natural slopes of 1, 5, 10 and 15%. The soil and crop management treatments consisted of bare fallow (plowed), maize-maize (plowed and mulched), maize-maize (plowed), maize-cowpeas (no-till), and cowpeas-maize (plowed).Total loss of nutrient elements in runoff and eroded soil materials was significantly affected by slope and by soil and crop management treatments. Total annual nutrient element losses in runoff were 55 kg/ha for bare-fallow, 17 kg/ha for maize-maize (plowed), 12 kg/ha for cowpeas-maize (plowed), 2.3 kg/ha for maize-maize (plowed and mulched) and 4.3 kg/ha for maize-cowpeas (no-till). The concentration of nitrate in seepage water was two or three times higher than in surface water. Nutrient losses in eroded soil materials from the mulched and no-till treatments were negligible. From the plowed treatments, greatest losses were of organic matter and total nitrogen. The enrichment ratios were 2.4 times for organic carbon, 1.6 times for N, and 5.8 times for available phosphorus. 相似文献