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试论山地的生态特征及山地生态学的研究内容

生物多样性 2004年第1期12卷 10-19页

作者：方精云沈泽昊崔海亭北京大学环境学院生态学系

山地是一个生态复杂系统 ,它具有特定的结构和功能 ,拥有丰富的生物多样性资源、水资源、矿产资源和旅游资源。开展山地生态学研究对阐明山地系统的结构与功能、山地的生态现象与过程 ,以及合理开发利用和保护山地资源都有极为重要的意... 详细信息

山地是一个生态复杂系统 ,它具有特定的结构和功能 ,拥有丰富的生物多样性资源、水资源、矿产资源和旅游资源。开展山地生态学研究对阐明山地系统的结构与功能、山地的生态现象与过程 ,以及合理开发利用和保护山地资源都有极为重要的意义。本文在简要分析山地地形的主要要素对生态因子影响的基础上 ,对山地的生态效应进行了归纳 ,探讨了山地生态学应包含的主要研究内容。作者认为 ,在山区 ,地形地貌是形成山地结构和功能以及各种生态现象和过程的最根本因素 ,它通过改变地表的光、热、水、土、肥等生态因子而发生作用。因此 ,山地生态学应把地形地貌与各种生态现象和过程的相互作用作为其核心的研究内容。作者提出 ,山地生态学研究主要包括 :山地生态复杂性与生物多样性、山地气候变化、山地生态工程、山区可持续发展综合研究以及山地生态学研究技术与方法论等内容。

关键词：山地地形要素生态效应生物多样性自然资源山地生态学

河北小五台山北坡植物物种多样性的垂直梯度变化

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生物多样性 2004年第1期12卷 137-145页

作者：刘增力郑成洋方精云北京大学环境学院生态学系

通过野外群落调查 ,分析了小五台山北坡植物物种多样性的垂直梯度变化。结果表明 :(1)小五台山北坡的物种丰富度随海拔的升高逐渐减小 ,物种组成趋于简单 ,乔木树种渐少。α多样性指数变化较小 ,但呈现出随海拔升高先增大、后减小的趋势... 详细信息

通过野外群落调查 ,分析了小五台山北坡植物物种多样性的垂直梯度变化。结果表明 :(1)小五台山北坡的物种丰富度随海拔的升高逐渐减小 ,物种组成趋于简单 ,乔木树种渐少。α多样性指数变化较小 ,但呈现出随海拔升高先增大、后减小的趋势。 (2 ) β多样性指数很好地反映了群落之间的变化。相异系数峰值出现在海拔 14 0 0 -15 0 0m处灌丛向森林的过渡带和海拔 2 6 0 0 - 2 70 0m处森林向亚高山草甸的过渡带。海拔 14 0 0 - 15 0 0m处出现的Cody指数极大值反映了灌丛群落向森林群落的变化 ,而Cody指数在海拔 2 10 0 - 2 2 0 0m的极大值反映了阔叶林和针叶林之间的过渡。 (3.作为小五台山两种最为重要的阔叶树种 ,白桦 (Betulaplatyphylla)和红桦 (Betulaal bo sinensis)沿海拔梯度出现明显的替代现象 ,随着海拔的升高 ,白桦逐渐为红桦所取代。

关键词：小五台山北坡垂直格局物种多样性植物

河北小五台山主要植被类型的分布与地形的关系:基于遥感信息的分析

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生物多样性 2004年第1期12卷 146-154页

作者：刘增力郑成洋方精云北京大学环境学院生态学系

小五台山是河北省最高峰 ,具有较完整的暖温带植被垂直带谱。本文通过野外群落植被调查 ,结合由TM遥感影像解译 1 5 0 0 0 0地形图制作的DEM数据而得到的植被图 ,分析了小五台山主要植被群落的分布状况及其与地形的关系。结果表明 ,... 详细信息

小五台山是河北省最高峰 ,具有较完整的暖温带植被垂直带谱。本文通过野外群落植被调查 ,结合由TM遥感影像解译 1 5 0 0 0 0地形图制作的DEM数据而得到的植被图 ,分析了小五台山主要植被群落的分布状况及其与地形的关系。结果表明 ,小五台山从低海拔到高海拔 ,依次出现灌丛、阔叶林、针阔混交林、暗针叶林、矮林、灌丛、草甸等植被类型。森林景观的面积最大 ,占总面积的 6 0 .7% ;平均斑块面积最大的是阔叶林和亚高山草甸 ,斑块破碎化最严重的是水体和针阔混交林。不同的植被类型在不同的地形条件下分布特点不同 ,林地在北坡所占面积比例 (占总面积的 75 % )远大于南坡 (4 6 % ) ,说明水分条件是小五台山森林分布的限制因子之一 ;灌丛和草甸与林地相反。随海拔高度的变化 ,不同植被类型的分布面积比例发生变化 ,出现替代现象 ,形成植被垂直带谱。由于坡度的影响 ,增加了带谱内植被组成的复杂性。

关键词：小五台山植被 DEM 遥感植被图多样性

Characteristics and dynamics of the soil seed bank at the north edge of Taklimakan Desert

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Science china earth sciences 2007年第S1期 122-127页

作者： LI Ning1,2, FENG Gu1,3.& TIAN ChangYan1 1 Xinjiang Institute of Ecology and Geography, Chinese Academy of Science , ürümqi 83.011, china 2 Graduate university of Chinese Academy of Science, beijing 100049, china 3.Chinese Agricultural university, college of Resources and environmental sciences, beijing 100094, china

In order to understand the potential of revegetation of halophytic community at the north edge of Taklimakan Desert, the species structure, storage capacity, the vertical distribution pattern and seasonal dynamics of soil seed bank and their interrelationship with community structure of above-ground plants were investigated. The results show that (i) 9 species were identified from seed bank in different seasons indicating that plant composition in this area was simple. (ii) The seed density in soil was 222±10.79 grain/m2 on average, and showed a seasonal variation range from 13.±8.16 grain/m2 in summer to 3.3.12.70 grain/m2 in autumn. (iii) The similarity coefficient between soil seed bank and above-ground vegetation was 0.778. (iv) Vertically, seed densities declined with soil depth. 82.4% of total seeds were found in the top 3.cm of soil profile. No active seeds were found in soil profile below 6 cm. It is concluded that the seed bank at the north edge of Taklimakan Desert contains active seeds of all plant species observed on above ground, and is able to supply potential contribution to reconstruction of vegetation.

关键词： Taklimakan Desert soil seed bank characteristics dynamics

Plant Diversity Reduces the Effect of Multiple Heavy Metal Pollution on Soil Enzyme Activities and Microbial Community Structure

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Plant Diversity Reduces the Effect of Multiple Heavy Metal P...

高黎贡山种子植物物种丰富度沿海拔梯度的变化

第六届全国环境化学大会暨环境科学仪器与分析仪器展览会

作者： Yang Gao~(1,4),Jun Xia~1,Yafeng Wang~2,Chiyuan Miao~3.Pei Zhou~4 (1.Key laboratory of Water Cycle and Related Land surface processes,Institute of Geographic {3. and Natural Resources Research,Chinese Academy of {3.,beijing 100101,china 2.State Key laboratory of Urban and Regional Ecology,Research Center for Eco-environmental {3.,Chinese Academy of {3.,beijing 100085,china 3.{13. of Global Change and earth System Science,beijing Normal university,beijing 100078,china 4.School of Agriculture and Biology,Shanghai Jiaotong university,Shanghai 200240,china)

＜正＞It is unclear whether certain plant species and plant diversity could offset the impacts of multiple heavy metal pollution on soil microbial structure and soil enzyme *** amplified polymorphic DNA（RAPD） was used to analyze the genetic diversity and microbial similarity in planted and unplanted soil under combined cadmium （Cd） and lead（Pb） pollution.A metal hyperaccumulator,Brassica juncea,and a common plant,Festuca arundinacea Schreb,were used in this *** results showed that micro-organism quantity in planted soil significantly increased,compared with that in

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生物多样性 2004年第1期12卷 82-88页

作者：王志恒陈安平朴世龙方精云北京大学环境学院生态学系

物种丰富度沿海拔梯度的分布格局成为生物多样性研究的热点。为探讨中尺度区域物种丰富度沿海拔梯度的分布 ,本文以高黎贡山为研究对象 ,利用该地区的地方植物志资料 ,结合通过GIS生成的区域数字高程模型(DEM)数据 ,分析了该区域全部种... 详细信息

物种丰富度沿海拔梯度的分布格局成为生物多样性研究的热点。为探讨中尺度区域物种丰富度沿海拔梯度的分布 ,本文以高黎贡山为研究对象 ,利用该地区的地方植物志资料 ,结合通过GIS生成的区域数字高程模型(DEM)数据 ,分析了该区域全部种子植物和乔木、灌木、草本三种生活型种子植物物种丰富度的垂直分布格局以及物种密度沿海拔梯度的变化特征。结果表明 :(1)全部种子植物和不同生活型植物物种丰富度随着海拔的升高呈现先增加后减小的趋势 ,最大值出现在海拔 15 0 0 - 2 0 0 0m的范围 ;(2 )物种密度与海拔也呈现单峰曲线关系 ;(3.物种丰富度和物种密度分布格局的形成主要受海拔所反映的水、热状况组合以及物种分布的边界影响。

关键词：物种丰富度物种密度生活型垂直格局海拔梯度地形植物

Object-oriented land cover classification using HJ-1 remote sensing imagery

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Science china earth sciences 2010年第S1期53卷 34-44页

作者： SUN ZhongPing1,SHEN WenMing1,WEI Bin1,LIU XiaoMan1,SU Wei2,ZHANG Chao2 & YANG JianYu2 1 Satellite Environment Center,Ministry of environmental Protection,beijing 100094,china 2 {3. of Information and Electrical Engineering,china Agricultural university,beijing 100083.china 1. Satellite Environment Center Ministry of Environmental Protection Beijing 100094 China2. College of Information and Electrical Engineering China Agricultural University Beijing 100083 China

The object-oriented information extraction technique was used to improve classification accuracy,and addressed the problem that HJ-1 CCD remote sensing images have only four spectral bands with moderate spatial *** used two key techniques:the selection of optimum image segmentation scale and the development of an appropriate object-oriented information extraction *** the principle of minimizing merge cost of merging neighboring pixels/objects,we used spatial autocorrelation index Moran's I and the variance index to select the optimum segmentation *** Nearest Neighborhood(NN) classifier based on sampling and a knowledge-based fuzzy classifier were used in the object-oriented information extraction *** this classification step,feature optimization was used to improve information extraction accuracy using reduced data *** two techniques were applied to land cover information extraction for Shanghai city using a HJ-1 CCD *** indicate that the information extraction accuracy of the object-oriented method was much higher than that of the pixel-based method.

关键词： HJ-1 remote sensing imagery object-oriented optimum scale of image segmentation Nearest Neighborhood(NN) classification fuzzy classification

Carbon dioxide exchange and the mechanism of environmental control in a farmland ecosystem in North china Plain

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Science china earth sciences 2006年第S2期49卷 226-240页

作者： LI Jun, YU Qiang, SUN Xiaomin, TONG Xiaojuan, REN Chuanyou, WANG Jing, LIU Enmin, ZHU Zhilin & YU Guirui Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101,{3. Graduate university of the Chinese Academy of sciences, beijing 100049,{3. college of Resources and environmental studies, beijing Forestry university, beijing 100083.{3. 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. Graduate university of the Chinese Academy of sciences Beijing 100049 China 3. college of Resources and environmental studies Beijing Forestry University Beijing 100083 China

CO2 flux was measured continuously in a wheat and maize rotation system of North china Plain using the eddy covariance technique to study the characteristic of CO2 exchange and its response to key environmental factors. The results show that nighttime net ecosystem exchange (NEE) varied exponentially with soil temperature. The temperature sensitivities of the ecosystem (Q10) were 2.94 and 2.49 in years 2002-2003.and 2003.2004, respectively. The response of gross primary productivity (GPP) to photosynthetically active radiation (PAR) in the crop field can be expressed by a rectangular hyperbolic function. Average Amax andαfor maize were more than those for wheat. The values ofαincreased positively with leaf area index (LAI) of wheat. Diurnal variations of NEE were significant from March to May and from July to September, but not remarkable in other months. NEE, GPP and ecosystem respiration (Rec) showed significantly seasonal variations in the crop field. The highest mean daily CO2 uptake rate was -10.20 and -12.50 gC·m-2·d-1 in 2003.and 2004, for the maize field, respectively, and -8.19 and -9.50 gC·m-2·d-1 in 2003.and 2004 for the wheat field, respectively. The maximal CO2 uptake appeared in April or May for wheat and mid-August for maize. During the main growing seasons of winter wheat and summer maize, NEE was controlled by GPP which was chiefly influenced by PAR and LAI. Rec reached its annual maximum in July when Rec and GPP contributed to NEE equally. NEE was dominated by Rec in other months and temperature became a key factor controlling NEE. Total NEE for the wheat field was -77.6 and -152.2 gC·m-2·a-1 in years 2002-2003.and 2003.2004, respectively, and -120.1 and -165.6 gC·m-2·a-1 in 2003.and 2004 for the maize field, respectively. The cropland of North china Plain was a carbon sink, with annual -197.6 and -3.7.9 gC·m-2·a-1 in years 2002-2003.and 2003.2004, respectively. After considering the carbon in grains, the cropland became a carbon source, which was

关键词： net ecosystem exchange gross primary productivity ecosystem respiration carbon budget eddy covariance winter wheat summer maize.

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神农架南坡植物群落多样性的海拔梯度格局

生物多样性 2004年第1期12卷 99-107页

作者：沈泽昊胡会峰周宇方精云北京大学环境学院生态学系

神农架南坡在我国植被区划中具有十分重要的意义。在神农架南坡沿海拔梯度设置 5 0个样方进行植物物种多样性调查 ,通过对样方的数量分类和DCA排序 ,结合物种丰富度、区系分化强度、区系成分和生活型构成等方面的分析 ,研究神农架南坡... 详细信息

神农架南坡在我国植被区划中具有十分重要的意义。在神农架南坡沿海拔梯度设置 5 0个样方进行植物物种多样性调查 ,通过对样方的数量分类和DCA排序 ,结合物种丰富度、区系分化强度、区系成分和生活型构成等方面的分析 ,研究神农架南坡植物物种多样性的垂直格局。结果表明 :(1)神农架南坡的植被垂直带谱为 :海拔 90 0- 10 0 0m以下为常绿阔叶林 ;10 0 0 - 170 0m为常绿落叶阔叶混交林 ;16 0 0 - 2 10 0m为落叶阔叶林 ;海拔 2 0 0 0 -2 4 0 0m为针阔叶混交林 ;海拔 2 3. 0m以上为暗针叶林。 (2 )植被基带群落中 ,在物种数量、区系成分和重要值方面 ,常绿和落叶阔叶树种所占的比例都相差无几。 (3.植物多样性的垂直格局基本符合“单峰”模式。峰值出现在海拔 14 0 0 - 15 0 0m ;但混交林类型的多样性和区系分化强度较高。 (4 )在植物区系中 ,温带成分处于主导地位 ;世界广布属的比例随海拔上升而增加 ;而中国特有属仅见于海拔 2 0 0 0m以下。亚热带成分和东亚区域性区系成分都随海拔上升而减少 ,峰值都位于山地常绿落叶阔叶混交林。 (5 )蕨类植物丰富度随海拔上升而减小 ;草本植物丰富度与海拔高度之间没有呈现显著的相关关系 ;木本植物丰富度总体沿海拔梯度减少 ,但峰椎处于常绿落叶阔叶林带。针阔混交林?

关键词：神农架垂直植被带谱多样性区系成分生活型