Modern pollen-vegetation relationship based on discriminant analysis across an altitudinal transect on Gongga Mountain, eastern Tibetan Plateau

Quantitative relationship between modern pollen assemblage and altitudinal vegetation belt is crucial for the reconstruction of paleovegetation in the mountain regions.Modern pollen analysis on 70 topsoil samples was conducted across an altitudinal transect(1100-4500 m) on the eastern slope of Gongga Mountain in the eastern Tibetan Plateau with an elevation interval of 50 m.Distributions of major pollen types along the transect indicated a weak correlation between Pinus pollen and the elevation.Distributions of Picea and Abies pollen(percentage sum of 2%-8%) could fairly indicate the elevation range of 2700-3700 m,as well as the subalpine dark coniferous forest and the timberline in the region.High percentage intervals of alpine types of Ericaceae,Cupressaceae and Cyperaceae were correlated to the high-elevation regions(3700-4500 m) dominated by alpine shrub meadow and alpine meadow.Seven altitudinal vegetation belts on the eastern slope of Gongga Mountain were well defined by discriminant analysis conducted on the modern pollen assemblages,as reflected by high values of probability of modern analog.Most of the modern pollen assemblages(88.5%) were typical for the vegetation types at their sampling locations.Thus,the relationship between the modern pollen assemblages and vegetation across the altitudinal transect based on discriminant analysis can be applied to the quantitative reconstruction of paleovegetation changes in the mountain regions of the eastern Tibetan Plateau.     

Modern pollen and vegetation relationships in the Yili Basin, Xinjiang, NW China

Fifty-six surface pollen samples from different vegetation zones in the Yili Basin,western Tianshan Mountains,Xinjiang were analyzed to examine the relationships between the surface pollen assemblages and the original vegetation.A pollen analysis and a vegetation investigation with a discriminant analysis show that the pollen assemblages greatly differ across disparate vegetation zones.Twelve pollen taxa can be used as significant types for vegetation reconstruction in the basin.These taxa were the most abundant in the surface pollen samples.Cupressaceae pollen percentages were greater than 1%in Cupressaceae shrubs.More than5%of Picea pollen indicates the growth of a Picea forest within 5 km.The subalpine meadow that is distributed widely in the basin is characterized by high content of Artemisia,Chenopodiaceae,Poaceae,Picea,Asteraceae,Taraxacum and Arenaria pollen types.The Artemisia-Chenopodiaceae-Poaceae-Cannabaceae pollen assemblages indicate the presence of montane steppe in the area.Artemisia and Chenopodiaceae pollen dominate the desert steppe and Populus forest.Artemisia pollen percentages were greater than 60%in the Artemisia desert,whereas Chenopodiaceae pollen percentages exceeded 65%in the Chenopodiaceae desert.The Artemisia/Chenopodiaceae(A/C)ratios reflect the vertical moisture changes in the Yili Basin.The mean A/C ratios were greater than 1.2 in the subalpine meadow and montane steppe that occupy the humid zone in the basin.These ratios were between1 and 1.2 in the Cupressaceae shrubs,desert steppe,Populus forest and floodplain meadow.The ratios were less than 0.5 in the Chenopodiaceae desert,which is an arid environment.     

近2000年来太白山高山带不同海拔植被对气候变化的响应

根据西佛爷池(海拔3410 m)剖面的有机地球化学指标, 重建太白山高山带过去2000年的气候变化。对采自该剖面的样品进行孢粉分析, 并结合太白山跑马梁(海拔3556 m)、三清池(海拔3080 m)和芳香寺(海拔3000 m)剖面的孢粉数据, 进行聚类分析, 探讨高山带不同海拔植被对气候变化响应规律。结果表明, 不同海拔植被对相对冷干气候的响应有更好的一致性, 且林线过渡带内这种一致性更明显。随着现代升温期的到来, 植被对气候的响应主要受高程影响。研究结果可为认识晚全新世以来高山环境系统的气候?植被耦合关系提供一定的参考。     

西藏亚高山暗针叶林的分布与生长

<正>一、西藏东南部拥有极丰富而特异的地貌类型、生态类型、生物种群和森林植被类型。藏东南林区有大面积古老,健康而完好的天然森林生态系统。其中亚高山暗针叶林是分布广、面积大、稳定性强、生物生产量高的森林群系。 二,西藏亚高山暗针叶林是寒温带暗针叶林分布最南、最高的林区之一。由于地带三向性的分异,亚高山暗针叶林有明显的水平分区和垂直分带。在各区,带中,森林群系,建群种,林型及其生长状况都有明显的差异。 三,西藏亚高山暗针叶林的水平分布可分为三亚区:(1)三江流域峡谷、山原块状暗针叶林亚区;(2)喜马拉雅山南麓高山峡谷湿润暗针叶林亚区;(3)雅鲁藏布江中下游沟谷暗针叶林亚区。 在分布区的海拔2700—4300米的垂直带内,分布有云杉林群系、冷杉林群系和圆柏林群系。各群系的分布带内,随水热状况的变化组成有规律的林型垂直分布带谱。 四、西藏亚高山暗针叶林的生长特点为;立木高大,生长持续期长,林分蓄积量高。在喜马拉雅山南麓湿润区,云杉林分的蓄积最高达每公顷3500余立方米,平均胸径111厘米,平均高67米。立木最大胸径162厘米,最大树高72米。 五、不同海拔高度与坡向的暗针叶林林分生长差异显著。在喜马拉雅山南麓湿润区,云杉的最适分布带在海拔2700—2800米,冷杉的最适分布带在海拔3600—3700米。北坡的林分生长远优于南坡。     

Pollen record from red clay sequence in the central Loess Plateau between 8.10 and 2.60 Ma

The origin and development of Asian monsoon circula-tion, the desertification and aridification of Asian inland in relation to vegetation evolution and the soil erosion in northwest China have been more and more drawing inten-sive scientific and society attention. Recently the studiesof monsoon evolution from some Tertiary Red Clay sec-tions located at the central Loess Plateau in the eastern Liupan Mountains, based on chronology, dust flux, grains size, magnetic susceptibility, and rates o…     

The surface pollen and relative pollen production of the desert vegetation of the Alashan Plateau, western Inner Mongolia

This preliminary investigation focuses on the comparison of the recent pollen precipitation and its related vegetation of eight different plant communities in the Alashan Region, the most western part of the Inner Mongolia Autonomous Region. Most zonal and azonal communities can be well identified by their pollen spectra. Relative pollen production factors of various plant taxa have been calculated and the following sequences from over-to under represented taxa have been found for zonal vegetation: Chenopodiaceae,Artemisia, Ephedra, Nitraria, Reaumuria, Calligonum, Zygo-phyllum; and for azonal vegetation: Peganum, Populus,Tamarix, Lycium.     

Methoxy n-fatty acids in surface soils from the Gongga and Kunlun Mountains: Ecological implications

GC-MS characteristics of surface soil samples from the eastern and northern Tibetan Plateau provide tentative identification of 8(–14)-Methoxy hexadecanoic acid (iME-16:0) and 9(–17)-methoxy octadecanoic acid (iME-18:0). Sixty surface soil samples were collected from the eastern slope of Gongga Mountain, at elevations ranging from ~1230 to 4500 m (eastern Tibetan Plateau), and from the northern slope of West Kunlun Mountains, ranging from ~1300 to 5500 m (northern Tibetan Plateau). This study also analyzed the methoxy n-fatty acids (MFAs) of Gongga Mountain tree leaves from six common living species, at the elevation of 2900–4200 m. MFAs dominate these samples, with more centrally located methoxy groups eluting earlier than those with methoxy groups located closer to the end of the main carbon chain. MFAs occur prominently in most of the Gongga Mountain soil samples (and from six tree samples) from dominantly coniferous and deciduous broadleaved forests. Other than in two narrow vegetation zones between 4000–4350 m and 2900–3300 m, no MFAs were found in 19 Kunlun Mountains soil samples from areas covered mainly with montane desert and alpine desert steppe vegetation. Based on the inventory of plants and soils from which MFAs have been isolated, we conclude that the MFAs most probably originate from specific woody plants. If we can exclude some particular grasses as sources, MFAs may be specific woody plants-derived biomarkers; thus they would serve as an important additional proxy for comprehensive and precise ecological reconstructions.     

A palynological and palaeoclimatological record from the southern Philippines since the Last Glacial Maximum

A palynological analysis of a marine sediment core in the southern Philippines,provides a detailed regional vegetation and climate history for the West Pacific Warm Pool(WPWP)since the Last Glacial Maximum(LGM).Chronology was determined by a detailed oxygen isotope record.A higher representation of pollen from tropical upper montane rainforest during the LGM indicate that this forest type moved down along elevation,probabaly due to the lowered temperature.During the last deglaciation and the early Holocene,mangroves were more expanded and tropical mid and upper montane rainforests were restricted,suggesting a rising sea-level and temperature increase.Herbaceous pollen and pteridophyte spore records indicate a much drier condition during the LGM than the Holocene.Mangrove development is controlled by conditions at the river mouth influenced by river discharge.Pteridophyte spores are abundant in wet conditions and are mainly transported by rivers.During the mid-Holocene,the reduction in mangrove pollen and pteridophyte spore appears to be a result of climate change:mainly decrease in river discharge.This may have been affected by the decreasing intensity of the Southeast Asian Monsoon,and the increasing frequency and intensity of warm ENSO events,El Ni?o,in this region.     

甘肃寿鹿山马麝隔离小种群的资源现状与保护

在寿鹿山自然保护区3个呈隔离状态的林区内，就3种不同林型马麝的种群密度进行了比较研究.结果显示老虎山林区马麝密度为10.20～71.11头/km2,长岭山林区马麝密度为17.93头/km2, 寿鹿山林区马麝密度为3.90～18.36头/km2.研究还表明，云杉乔木林和灌木林马麝密度较高，斑块状分布的灌丛有利于马麝栖息，稀疏灌木地、草地以及高而浓密呈连续分布的灌丛则不利于马麝栖息.     

中国不同植被类型净初级生产力变化特征

收集、统计了1993—2011年所发表的98篇涉及我国不同植被NPP数据(模型模拟估算值和实测值)的代表性论文.分析了我国不同植被类型NPP研究结果及其变化和空间分布特征.结果表明:1)模型模拟和实测NPP值都较高的植被类型有热带雨林、季雨林,常绿阔叶林,常绿针叶林、混交林和落叶阔叶林;2)模型模拟的植被NPP值空间分布规律基本表现为从东南沿海地区依次向西北内陆递减;3)在模型模拟与实测NPP值所共有的9种植被类型中,除耕地、灌丛和草地的模型模拟NPP值略大于实测值,其余6种植被类型均小于实测值;4)不同模型对同一种植被类型的模拟结果之间表现出了极大的差异;5)模型模拟平均值与实测值之间的差异相对较小,采用已提出的模型模拟平均值来估算我国不同植被的NPP是基本可行的.     

青海湖北岸植物群落的数量分类

依据对青海湖北岸植物群落的踏查和对鸟岛、大通山,以及海晏湾3个地区的野外取样调查,比较讨论了重要值的各类计算公式.认为,在草地植物群落中用重要值=(相对盖度+相对频度)/2×100比较科学,并用组平均法(GAM)对该地区植物群落进行了分类,划分为24个群落,分别属于沙生植被、沼泽草甸、草甸、温性草原、高寒草甸、高寒灌丛及高山流石滩稀疏植被等7个植被型.     

Vegetation evolution and its response to climatic change during 3.15–0.67 Ma in deep-sea pollen record from northern South China Sea

In order to study vegetation evolution and environmental change during 3.15-0.67 Ma,a total of 608 pollen samples with an average time resolution of 4 ka has been analyzed from ODP Site 1145(water depth 3175 m),northern South China Sea.The deep-sea sediments(213.62-91.9 m) cover from 3.15 to 0.67 Ma based on micropaleonotological stratigraphy.The characteristic features of the pollen diagram include that,pollen influx rises twice obviously around 2.58 Ma and during 2.0-1.8 Ma,in response to global climatic cooling and winter monsoon enhancement.Before 2.58 Ma,tropical and subtropical vegetation,mainly evergreen Quercus(E) and Altingia,predominated around northern SCS with much more tropical montane conifers and ferns relatively.From 2.58 Ma,temperate vegetation increased obviously,implying climatic cooling and winter monsoon enhancement.Spectral analysis shows that percentage variation in tropical and subtropical taxa has a strong 20 ka procession cycle probably due to the summer monsoon;while pollen influx has 100,41 and 19 ka cycles,indicating the sea level and winter monsoon change response to the ice-sheet variations.     

1982—1999年我国植被净第一性生产力及其时空变化

基于地理信息系统和卫星遥感技术,利用植被、气候和土壤等地面空间数据,应用CASA模型估算了1982—1999（除1994）年间我国植被年净第一性生产量及其时空变化。结果表明：18年间我国植被净第一性生产量呈增加趋势,平均增加速率为0.024PgC·a^-1,其均值为1.8PgC,其中高寒植被、常绿阔叶林和常绿针叶林的增加速度最快;降水是限制我国植被净第一性生产力的主要因子。     

广西植被调查、分类与植被志研编方案

广西是我国植被类型较丰富的省区之一,开展《广西植被志》研编意义重大。本文在全面总结广西植被调查研究历史的基础上,将植被调查研究的进程分为3个阶段：第一阶段为1950-1980年,第二阶段为1981-1999年,第三阶段为2000年至今。对《广西森林》《广西植被志要》和《广西植被(第一卷)》中的植被分类原则、等级、分类结果及各分类系统的特点进行分析比较。在遵循《中国植被志》的研编标准及规范的基础上,提出《广西植被志》的研编方案,建议以植被型组独立成卷,即可分为6卷：森林卷、灌丛卷、草丛卷、沼泽与水生植被卷、农林植被卷、城市植被卷。其中,森林卷可分为6册,即针叶林和针阔叶混交林分册、落叶阔叶林分册、常绿落叶阔叶混交林分册、常绿阔叶林分册、季雨林和雨林分册、竹林分册;灌丛植被、草丛植被和沼泽与水生植被各独立成卷;农林植被卷分为两册,分别是农业植被分册和林业植被分册;城市植被独立成卷。此外,加上第一卷总论,《广西植被志》可由7卷13册组成。对建立10个植被信息数据库及广西数字植被大数据平台提出初步方案。《广西植被志》的研编及出版必将推动广西植被生态科学的进一步发展。     

广西植被资源保护现状与策略

【目的】全面了解广西植被资源保护现状、受威胁原因及保护空缺,为制定广西植被资源保护策略和生物多样性保护行动计划提供科学依据。【方法】在全面收集广西植被资源信息数据的基础上,通过比较分析和空缺分析,揭示植被资源保护现状及受威胁原因。【结果】植被保护成效显著：建立了较完善的植被保护法律、法规体系,建立各种类型的自然保护区78个,面积达145.90万hm2,占广西国土面积的6.17%;这些自然保护区保存了广西40大片原生性最好的天然阔叶林,保护了广西90%的野生动植物种群和80%以上的森林植被类型,保护了全区19.8%的自然湿地和70%的重要湿地。植被保护现状：天然植被退化的严重局面还没有从根本上得到有效遏制,一些特有、珍稀植被资源尚未得到有效的保护,经济社会高速发展对天然植被保护的约束压力加大,天然植被缩小、人工植被扩大,植被的生态功能下降。植被受威胁的原因主要是：人口过快增长、城市化和土地开发、森林火灾、病虫害、气候灾害、桉树人工林的无序发展、湿地开垦与污染等。植被保护空缺仍然较大,有66种森林、17种竹林、72种灌丛、45种草丛、120种水生植被尚未得到有效保护。提出了广西植被资源保护的重点区域和重点保护类型。【结论】广西植被资源基本得到保护,但保护与开发利用之间的矛盾尖锐,构筑国土生态屏障和经营优质生态资产的任务任重道远。     

青海湖北岸植被特征研究

根据青了孔和ＱＨ８５－１４Ｃ孔的孢粉分析资料以及对青海湖北岸植物群落的系统取样调查，对该地区的植被进行了区系、生活型、演变趋势及环境因子等综合研究。结果表明：（１）该地区现有种子植物２６科、７５属、１４２种，其地理成分复杂，分布区交错，起源有老有新，特有种、属少，种类不多；（２）自然植被可分为７个植被型、２４个群落；（３）与本地区高寒的气候特征相适应，植物群落以地上芽植物和隐芽植物为主；（４）全新世以来，随着气候由暖→冷，湿→干、植被演变趋势为森林草原→森林→温性草原；（５）影响植被分异的主要环境因子为海拔（热量）、大气温度和大气湿度。     

尖峰岭次生林和原始林林下灌木叶氨基酸对氮添加的响应

为了深入地了解热带山地雨林原始林与次生林叶氨基酸对氮添加的响应和适应机制, 以海南尖峰岭热带山地雨林原始林和次生林的林下常见植物为研究对象, 通过设置对照CK (0 kg N/(ha·a))、中氮添加M (50 kg N/(ha·a))和高氮添加H (100 kg N/(ha·a)) 3种氮添加处理的实验, 探究氮添加对林下灌木叶片氨基酸含量的影响。实验结果表明, 无氮添加时, 原始林与次生林的总氨基酸含量和水解氨基酸含量无显著差异, 原始林游离氨基酸总含量显著高于次生林; 中氮添加时, 次生林林下灌木叶氨基酸含量的响应程度高于原始林; 高氮添加时, 次生林与原始林林下灌木水解氨基酸的响应程度无显著差异, 原始林林下灌木游离氨基酸的响应程度高于次生林。     

基于RS-GIS梵净山植被分布规律的研究

随着气候环境的变化,植被类型的分布与其生长环境也受到了严重的影响,以梵净山自然保护区为例,通过GIS空间分析功能定量分析了梵净山自然保护区植被分布情况,并结合相关环境数据对影响梵净山的植被分布进行统计分析,通过分析不同植被类型与气温、降水、海拔、坡度和坡向5个环境因子的关系,结果显示,坡度是影响梵净山植被类型分布格局的主要因素,并得出了梵净山各植被类型的最优发育环境区间,通过揭示植被与环境的相互关系及影响,将有助于梵净山自然保护区的管理与植被保护。     

Quantitative relationships between vegetation and several pollen taxa in surface soil from North China

According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast China Transect (NECT), several pollen taxa, includingPinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part.Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa.Acer, Gramineae and Cyperaceae, which have small slope andy-intercept terms, were under-representative taxa.Quercus, Tilia andUlmus whose slope terms have negative correlation withy-intercept terms were equi-representative taxa. The pollen taxa with large slope or largey-intercept terms have small variability coefficients, implying that the slope andy-intercept terms for these pollen taxa are of high accuracy in the estimation of plant abundance from pollen frequencies.     

青海海北高寒草甸植被多样性研究

本文对青藏高原高寒草甸和灌丛植被的分布、植物区系、生态特征进行了简要介绍,重点分析了青海海北地区高寒草甸植被类型、层片结构、生态型的多样性以及植物物种多样性、植物功能群多样性,旨在为高寒草甸生态系统的深入研究提供基础资料及科学依据.