共查询到19条相似文献,搜索用时 171 毫秒
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以女儿寨小流域为研究对象,着重研究了植被恢复重建过程中小流域系统的小气候变化特征。随着小流域内的植被恢复与重建,小流域内最高气温约降低了1~4℃,尤其以夏、秋季更为突出,约降低了3~4℃;最低气温提高了1~2℃,夏季较其它季节更为显著一些;森林不能降低小流域的日平均气温,但能略微增加秋冬季的平均气温0.1~0.5℃;平均地面温度降低了0.9~1.3℃,秋冬季的地面平均温度略微增加0.1~0.5℃;年降水量增加了77~115mm;年蒸发量降低105~175mm。小流域小气候环境发生了较大的变化,小气候质量在不断的提高。 相似文献
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四川西部干旱河谷自然特征及植被恢复与重建途径 总被引:14,自引:15,他引:14
本文分析阐明了四川西部干旱河谷的特点、形成及其发展趋势,对干旱河谷生境进行了分类,并针对各类型或亚类型提出了植被恢复与重建的途径、方法及其配置的植物种类,同时提出了今后需要解决的问题及研究的课题。 相似文献
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草海国家级自然保护区植被恢复与重建初探 总被引:2,自引:0,他引:2
文章分析了草海自然保护区植被的生境、现状和演替规律,从恢复生态学原理出发,以水热等气候因子所决定的植被生物地带性为科学依据,提出以人工造林和封山育林等措施恢复与重建森林植被,以政策措施、生物措施和工程措施等恢复与重建湿地植被。 相似文献
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建设生态城市,实现城市的可持续发展,就要有良好的生态环境,为此,必须大幅度提高植被覆盖率,营建城市森林隔离林带、大面积绿地。由于城市环境与自然环境存在很大差异,城市植被的恢复与重建有其固有的规律,这也是受到普遍关 相似文献
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本文通过对西北地区生态环境问题形成的历史原因及现状分析,得出该区域主要的生态环境问题包括森林和草原生态破坏、水资源和水生态破坏、水土流失和土地荒漠化等方面。同时,依据该区域生态环境脆弱特性及植被在生态环境建设中的恢复机理,提出较为具体的植被恢复措施,试图为西北地区生态环境的恢复重建提供参考。 相似文献
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Effects of forest vegetation on runoff and sediment transport of watershed in Loess area, west China
This paper aims to study the effects of vegetation on runoff and sediment transport at the watershed scale, and to provide
a theoretical basis for afforestation in the Loess area, in the nested Caijiachuan watershed, Jixian County, Shanxi Province
of west China. Forest watersheds and farmland watersheds with similar terrain features were selected through cluster analysis
to study their runoff and sediment transport characteristics. Results showed that compared with farmland watersheds, runoff
generation time in forest watersheds was delayed remarkably, and peak flow was reduced greatly, which indicates that vegetation
played an important role in holding and absorbing rainfall. Besides, with the increase of forest coverage, the runoff amount,
runoff depth and runoff coefficient decreased during the rainy seasons. The runoff depth and runoff coefficient of farmland
watersheds in the rainy season were 5–20-fold as much as that of forest watersheds, and runoff and sediment yield of watersheds
with low forest coverage were 2.7–2.9-fold and 3–6-fold as great as those with high coverage during rainstorms, and low forest
coverage had larger variation in sediment hydrograph. For the complexity and scale dependence of the influence of forest vegetation
on runoff, forest hydrological functions based on regional scale or watershed scale were worthy of further studies.
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Translated from Science of Soil and Water Conservation, 2006, 4(3): 48–53 [译自: 中国水土保持科学] 相似文献
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采用"空间代替时间"方法建立退化群落自然恢复演替系列,以"最优分割法"划分群落演替阶段,对广西西南部喀斯特植被群落特征进行了研究。研究表明森林群落在群落结构上分为乔木层、灌木层和草本层3个层次,乔木层树木高度多在20 m以下,胸径在12 cm以下个体可达89.85%;灌木层个体高度一般不超过2 m,以乔木层幼苗幼树居多;草本层高度在0.5 m以下。草本、灌木群落所处生境比较恶劣,多为耐旱耐瘠薄单优群落,物种组成单一,群落高度3 m以下。群落生物多样性总体呈上升趋势,而均匀度呈下降趋势。Simpson指数在演替初期为0.76左右;演替中期上升为0.81~0.94;而演替后期下降为0.73~0.94。Shannon-Wiener指数由演替初期的1.59上升到演替中期的2.01~3.47,到演替后期下降为1.31~2.67。群落均匀度指数JD在演替初期为0.029~0.095;到演替中期下降为0.016~0.059;在演替后期群落均匀度上升到0.06以上。研究区域植被群落特征与经典演替理论群落特征变化有所不同,但与生态系统在适度干扰下多样性较高的适度干扰理论相一致,说明桂西南喀斯特生态系统经常受到外界干扰。 相似文献
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Xiaoming Zhang Xinxiao Yu Sihong Wu Tianxing Wei Xuepei Zhang 《Frontiers of Forestry in China》2006,1(3):336-342
According to fixed-position data for 1985–2003 from nine runoff plots of Caijiachuan watershed which lies in Jixian County
of Shanxi Province in Loess area, this paper studied the relationship between vegetation and runoff and sediment production
in sloping lands in detail, which helps to provide scientific basis for vegetation re-construction and studies on environmental
transformation of water and sediment in watersheds of Loess area. Although, many study results testify that forest vegetation
has an important function in soil and water conservation and cutting runoff, the effect of vegetation on runoff and sediment
transmission is complicated, and this needs to be studied in depth. The results of the paper showed the following. Firstly,
the natural secondary forest performs better function of soil and water conservation than artificial Robinia pseudoacacia forest, and runoff and sediment produced in the former in individual rainfall were 65%–82% and 23%–92% of those produced
in the latter. At the same time, better correlative relationship between runoff and sediment production and rainfall and rainfall
intensity were testified by multiple regression, but the correlation decreased gradually with the increase of canopy density
of forest. Secondly, the difference of runoff and sediment production in several land use types was very distinct, and the
amount of runoff and sediment produced from Ostryopsis davidiana forest and natural secondary forest were the least, and runoff and sediment produced from in artificial Robinia pseudoacacia forest and Pinus tabulaeformis forest were 5-fold as much as those from O. davidiana forest. Besides, runoff and sediment produced in mixed planting of apple trees and crops were 16.14-fold and 2.96-fold than
those of O. davidiana forest, respectively, but the amount decreased obviously after high-standard soil preparation in the case of the former.
Thirdly, based on gray cognate analyses of factors affecting runoff and sediment production in sloping land, the factors of
stand canopy density and herb and litter biomass were the most significant ones, whose gray incidence degree exceeded 0.6.
Therefore, mixed forest with multi-layer stand structure and shrub forest should be developed in vegetation re-construction
of Loess area, which will help to increase coverage and litter thickness in order to cut down the runoff and sediment dramatically
in sloping land.
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Translated from Chinese Journal of Applied Ecology, 2005, 16(9): 1,613–1,617 [译自: 应用生态学报, 2005, 16(9): 1,613–1,617] 相似文献
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本文总结国内外矿区植被恢复研究进展,系统提出阜新矿区植被恢复限制性因子,并根据该区特点进行适宜生态复垦措施,建立稳定、高效人工生态系统,是治理阜新矿区废弃地有效对策。 相似文献
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以武陵山区小流域马尾松林、枫樟混交林、杜仲林和坡耕地为研究对象,对其7.5、12.0、20.0 cm土层深度在典型降雨前后水分动态变化进行观测与分析,研究了林地土壤水分的日变化规律,从而为林水综合管理、流域科学治理以及森林多功能高效经营等提供科技支持。结果表明:1)所有观测时间内,在7.5和12.0 cm土层深度处,4种植被类型土壤含水量最大的均是杜仲林,其次是枫樟混交林,最低的是坡耕地,土壤水分随深度增加而降低;在20.0 cm土层深度处,杜仲林和枫樟混交林差异不显著,马尾松林与坡耕地差异显著;3个土层深度下,4种植被类型土壤含水量均为杜仲林>枫樟混交林>马尾松林>坡耕地。2)降雨前, 4种植被类型的土壤含水量均比较稳定,只在7.5和12.0 cm处缓慢减少;降水后,4种植被类型的土壤含水量明显增加,增加幅度最大的是7.5 cm的马尾松林,其次是12.0 cm的坡耕地。3)降水前后,4种植被类型的土壤含水量与风速和大气温度均呈负相关关系,土壤的含水量与湿度呈正相关关系。4)综合分析表明杜仲林的土壤含水量最大,其作为生态经济型树种,具有较好的水源涵养能力,可大面积示范推广有利于提高研究区的生态效益。 相似文献
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大红山铁矿林草植被水土保持效益的研究 总被引:2,自引:0,他引:2
以裸地为对照,分别对土壤物理性状及土壤的渗透性,土壤中含水量的动态变化,地表径流及土壤流失量等进行了定点定量观测。研究结果表明,林地与草地能有效改善土壤物理性状、增强土壤渗透性和降低土壤水分含量;能通过提高土壤抗蚀性、改善土壤养分含量来充分发挥水土保持效益。研究结果还表明,林地和草地减少侵蚀效益较好,裸地的土壤流失最严重。与裸地相比,林地和草地对地表径流的控制率达到63%~89%,对土壤流失的控制率达到69%~94%。 相似文献
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通过借用退化沙荒地附近种源地土壤种子库的客土方式,分析客土+保水剂、客土2种不同措施对退化沙荒地土壤改良和植被恢复的作用,为沙荒地植被自然恢复与重建技术提供理论依据。结果表明:1种子库物种以多年生草本植物为主,且双子叶植物居多,未发现乔灌木植物种子,种子密度是种源地(1 524.64粒/m2)沙荒地(843.76粒/m2)。2土壤有机质、全氮、全磷、全钾、碱解氮、速效磷、速效钾含量在0~10cm土层内表现为:客土+保水剂客土沙荒地,在10~20cm和20~40cm土层内3种处理样地无明显差异。3客土和客土+保水剂处理地,其地上和地下生物量均远高于沙荒地,客土地的生物量(937.80g/m2)是沙荒地生物量(287.11g/m2)的3.27倍。但根冠比是沙荒地(1.85)客土(1.69)客土+保水剂(1.04),说明土壤干旱在某种程度上利于植物根系的发育。4不同改良措施下草本Margalef指数和Shannon-wiener指数,客土+保水剂客土沙荒地;Pielou指数和Simpson指数是客土地与客土+保水剂处理地之间相差不大,但都明显高于沙荒地。 相似文献
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Xiang Li Jian-zhi Niu Jiao Li Bao-yuan Xie Yi-ni Han Jing-ping Tan Ying-hu Zhang 《林业研究》2012,23(3):419-424
We studied the impact of forest vegetation on soil erosion,surface runoff, and sediment generation by using field simulated rainfall apparatus. We measured runoff and sediment generation of five 4.5 × 2.1m runoff plots (a bare soil as a control; two Pinus tabulaeformis forestplots and two Platycladus orientalis forest with row spacing of 1 m × 1m and 1.5 m × 1.5 m, respectively) in Beijing Jiu Feng National ForestPark under three rainfall intensities (0.42, 0.83, 1.26 mm per minute).Forest vegetation significantly reduced soil erosion and sediment yield.Mean total runoff volume in the four tree stand plots was 93% of that inthe control plot, demonstrating the limited effectiveness of forest vegetation in runoff control. With increasing rainfall intensity, runoff reductionin forest plots declined from 28.32% to 2.1%. Similar trends in runoff coefficient and the relationship between runoff volume and rainfall duration was observed. Mean total sediment yield and mean sediment yield reduction rate under different treatments was 55.05% and 43.17% of those in the bare soil control plot, respectively. Rainfall intensity playedan important role in runoff and sediment generation processes, and had agreater impact on runoff than on soil erosion and sediment generation.When considering several factors in runoff and sediment transport processes, the P. tabulae form plot with row spacing at 1 × 1 m had a greater effect on soil and water conservation than did other forested plots. 相似文献