浅论中亚热带湿润地区喀斯特森林植被的恢复

中亚热带湿润地区现存喀斯特森林植被较少,但该地区的环境条件有利于植物生长,只要充分应用植被演替规律。加强植被保护,有社会经济条件作保证,就可能在较短时间内恢复森林植被。本文列举了一些实例说明。     

贵州安顺小黑土晚更新世古植被和古气候

小黑土剖面是黔中高原岩溶化盆地剖面,深390cm,未达基岩.采样71块,获孢粉17769粒,有71个科属,以本本花粉为主,其次为草本花粉,蕨类孢子较少.自下而上划分为二个孢粉组合带.反映出古植被变化为落叶阔叶树为主的常绿、落叶针阔叶混交林,附近山地有松林及云杉林一常绿、落叶针阔叶混交林及喜冷湿的莎草较多.古气候变化由温凉一温暧偏凉湿.其地质时代,经~(14)C测定,孔深390cm处为24500±1800a.B.P.;深310cm处为21260a.B.P.,属晚更新世.     

论戈壁荒漠生态区植被的若干基本特征

戈壁荒漠生态区是亚非荒漠的一个组成部分.在漫长的自然历史演化过程中,戈壁荒漠塑造了自己独特的植物生态类群、协调适应的层片结构、奇异的群落组合以及宏观上呈巨型同心环带状展布的植被水平格局和大大地简化了的山地植被垂直带谱.从而构成了亚洲中部独有的戈壁荒漠景观.     

柳河泥沙的防治与综合治理

本文分析了柳河泥沙成因以及提出了防治与综合治理的措施.     

Pollen-recorded climate changes between 13.0 and 7.0 ^14C ka BP in southern Ningxia, China

A pollen record from Haiyuan section in the southern part of Ningxia revealed a detailed history of vegetation variation and associated climate changes during the period from~13.0 to~7.0 14 C ka BP.A steppe landscape under a moderately dry(and probably cool)condition(~12.7-~12.1 14 C ka BP)was replaced by a coniferous forest dominating the landscape under a generally wet climate from~12.1 to ~11.01 4C ka BP.This generally wet period,corresponding to the European B?lling/All?rod period,can be divided into three stages:a cool and wet stage between~12.1 and~11.4 14 C ka BP,a mild and rela- tively dry stage between~11.4 and~11.2 14 C ka BP,and a mild and wet stage between~11.2 and~11.0 14 C ka BP.The coniferous forest-dominated landscape was then deteriorated into steppe landscape (~11.0-~10.6 14 C ka BP)and further into a desert steppe landscape from~10.6 to~9.8 14 C ka BP,being correspondent to the European Younger Dryas period.After a brief episode of a cool and wet climate (~9.8-~9.6 14 C ka BP),a relatively mild and dry condition prevailed during the early Holocene(~9.6- ~7.6 14 C ka BP)and then a warm and humid climate started the mid-Holocene(~7.6-~7.2 14 C ka BP).     

封山育林是加快太行山绿化的重要途径

介绍了封山育林的概念和封山育林的优势,阐述了封山育林的对象、条件、类型、方式和封山育林的年限,提出了加快太行山封山育林的对策。     

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.