河西固沙林群落和林下土壤的演替发育及稳定性

通过对河西人工固沙林植被群落和土壤生物结皮演替发育及稳定性的调查发现,在降雨量大于100mm的地区,其人工固沙林群落的植物种在不断增加,向复杂、较稳定的方向演化;能固土保水,并能形成适宜的小气候环境,使沙丘面发育1cm~2cm厚的生物结皮,结皮下发生4cm~5cm的成土层,而且,不断向养分积累、层次分化、构型地带性的成土方向演化。在降雨量小于100mm的地区,人工固沙林虽然也能增加物种、固土保种、并形成一定的小气候环境,但是,由于其水分的补偿较少,所形成的小气候环境的作用微弱,又由于自然的旱化、盐化、沙化程度加重,人工植被群落先发生进展性演替,然后又向简单化、强度旱生化方向发展。从其发展阶段和速度而言,属于外因、次生、波动性演替。从生态系统的演替发育观出发,认为当土壤生物结皮物形成和良好发育才是流动沙丘趋于固定的标志。     

植被恢复与重建的生态功能特征研究概述

恢复、修复或重建被破坏的森林和其他自然生态系统,可增加林冠对降雨的截留作用,其凋落层是巨大的水分蓄积库,增强了系统水分涵养功能;植被的恢复和重建,通过改良土壤理化性质,达到在一定程度上增加土壤水分的入渗和土壤储水量,减少地表径流。     

Evaluation of Eco-Environmental Frangibility Based on Remote Sensing and Geographic Information System

The eco-environmental frangibility is studied by choosing the factors of land use class change and vegetation cover rate, and the equation of eco-environmental frangibility and its evaluation system are established based on remote sensing （RS） and geographic information system technology （GIS）. Four different years of TM images are selected to calculate land use change grads and vegetation cover rate, and the relationship between the two factors and eco-environment frangibility index are build, taking Fuzhou as an example. The character of times change and space distribution of eco-environment frangibility are described. The result indicates the area of eco-environment frangibility increased 2.6% in Fuzhou during twelve years, and expands from the region between infield and forest land to forest land in space distribution.     

Vegetation Spatial Heterogeneity of Different Soil Regions in Inner Mongolia, China

The vegetation spatial heterogeneity and ecological characteristics in different soil regions were analyzed by surveying the vegetation in 12 different soil regions of Inner Mongolia, China, including conifer- ous-broadleaf deciduous forests, shrub, grassland, and desert regions with 1122 large 2 cm × 2 cm quad- rats (actual size 30 km × 30 km, referred to as L-quadrat hereafter) in about 1.18 million km2. Each L- quadrat was divided into four small 1 cm × 1 cm quadrats (actual size 15 km × 15 km, S-quadrat). The vegetation was analyzed based on the beta-binomial distribution to describe the frequency of occurrence and spatial heterogeneity for each kind of vegetation. The weighted average of the heterogeneity of all vegeta- tion in the same soil region provides a measure of the soil regional landscape level heterogeneity which de- scribes the spatial complexity of the regional landscape composition of the existing vegetation. Comparison of the vegetation characteristics in the 12 soil regions shows that, the calcic gray soil has the highest average vegetation type per quadrat. The largest soil region is calcic chestnut soil and has the most vegetation types. Every soil region has its own dominant vegetation sequence which dominates in occurrence and dominant vegetation types which dominates in spatial heterogeneity. For the Inner Mongolian vegetation, the weighted average of the heterogeneity is 0.60 and the vegetation diversity index is 4.47.     

西部植被建设对我国整体生态环境的作用

我国整体生态环境的主要河流长江、黄河都起源于西部,近年来,由于生态恶化造成的沙尘风暴及洪涝灾害不断给全国造成影响和威胁,因此,西部的植被建设必然是关系全国整体生态环境的大事.     

历史文化名村保护中的植被修复与景观设计——以太原市店头古村落为例

以山西省太原市店头历史文化名村的保护为例,从山体植被、古树名木、特色资源等三方面的保护入手,同时结合村落及其周边环境景观设计,介绍和分析了店头村植被修复保护的具体措施和景观设计构想,也为其他地区历史文化名村的保护提供了思路。     

绿色能源背后的秘密

位于加利福尼亚州帕斯山附近的未建制社区．是一个极少为旅游者注意的区域——散乱不整的岩石和沙漠植被约书亚树．沿着15号公路连绵起伏。这块区域既没有引人注目的标志性建筑．如加州贝克镇附近竖在莫哈维沙漠中的高134英尺的温度计，又不像拉斯维加斯那样不到1小时车程就遍布赌场。     

林下植被对杉林土壤微量元素状况的影响

调查分析了赣中低山区不同林下植被类型（芒萁型，蕨类型和灌木－芒萁型）对杉森林土壤有效态微量元素（硼、钼、铜、锌、铁和锰）状况的影响。指出该地区森林土壤为硼，钼，铜和锰缺乏区，锌潜在缺乏区，铁富集区。     

植被砼边坡防护施工技术

为保证边坡稳定,保护生态平衡,体现高速公路绿化环保型特点,植被砼是边坡防护最适用、最常见的一种防护形式。     

Deep sea pollen record during 12－1.6 Ma from the southern South China Sea and its response to envi-ronmental change

Based on deep-sea pollen results (512-76 m) from ODP Site 1143 in the southern South China Sea (SCS),the climate and vegetation evolution sequence on the surrounding islands and the exposed continental shelf are discussed. The pollen records show that the pollen influx was quite low before 8.15 Ma and increased dramatically afterwards. The influx changes can be ascribed,on one side,to tectonics deformations around the southern SCS resulting in rapid uplift of islands and subsequent increase of the sediment rates and pollen influx and on the other side to climate cooling and monsoon enhancement. Around 2.63 Ma was another obvious boundary,the increasing of pollen and spores influx since this time was mainly related to global climate cooling. Spectrum analysis of pollen influx values shows that 2 Ma,0.67 Ma,and 0.19-0.17 Ma cycles existed during 12-3.0 Ma,while 0.1 Ma and 46.9 ka cycles existed during 3.0-2.0 Ma.