秦岭种子植物区系中的热带地理成分研究

对秦岭种子植物区系中的热带地理成分进行了研究,本区的热带地理成分共包括泛热带成分,热带亚洲和热带美洲间断成分,旧世界热带成分,热带亚洲至热带大洋洲成分,热带亚洲至热带非洲成分及热带亚洲成份等6种类型,共283属,648种,属数和种数分别占秦岭种子植物总属数及总种数的30．27％,18．80％,它们是秦岭植物区系组成的一个重要方面,在各类地理成分中,秦岭植物区系与泛热带成分联系最为密切,从热带地理成分的类型,分布以及在秦岭植被组成中的作用来分析,本区植物区系具有明显的温带性质,热带区系成分仅处于从属地位,多分布于低海拔地段或秦岭南坡,但本区植物区系的起源则带有强烈的热带渊源,而各类热带成分内部均有一定数量的属或分布至亚热带,或分布到北温带,又从一个侧面反映了秦植物区系的过渡性特点。     

陕西木本种子植物区系属的热带地理成分研究

对陕西境内木本种子植物区系属一级的热带地理成分进行了研究,全省木本种子植物区系中的热带地理成分共包括泛热带成分、热带亚洲和热带美洲间断成分、旧世界热带成分、热带亚洲至热带大洋洲成分、热带亚洲至热带非洲成分及热带亚洲成分6种类型,共95属,归属于53科。在各种热带地理成分中,陕西木本植物区系与泛热带成分联系最为密切,各类热带地理成分主要分布于陕西秦岭以南地区。从科、属、种的分布区格局以及木本热带区系成分的群落学作用等方面分析,陕西植物区系具有明显的温带性质,同时,区系也呈现一定的热带—温带过渡性特点。     

中国生物地理区划研究

首先将中版图根据综合自然（包括海拔、地形、气候、植被、水系、农业区等）因素,利用GIS技术手段,划分出124个基本单元。同时,根据一定的原则选择了171种哺乳类和509种植物物种,利用中国物种信息系统收集这些物种的分布信息,并运用GIS技术将这些信息转换为各个基本单元内这些物种存在与否的信息,再用数学量化分析方法,即Sφrensen相似性指数公式计算相关矩阵,以及Ward方法进行聚类分析,得到上述124个基本单元的哺乳类和植物分布相似性聚类图,从而最终得到一个新的定量化的、更具客观性和实用意义的中国生物地理区划系统,以及关于中国生物地理区划的许多重要结论。该区划包括4个区域（8个亚区域）、27个生物地理区和124个生物地理单元。采用从基本单元到高级区划的研究方法,在生物地理区划研究领域,这是一种方法学上的尝试,利用物种的分布相似性聚类结果来帮助确定区划界线,减少了对研究者自身所拥有的物种及生态学知识及经验的依赖,因而更具有客观性,较少掺杂研究者的主观臆断。这种方法也同样适用于其他生物门类区划的研究。     

松突圆蚧冷冻试验及其潜在地理范围北界的推测

松突圆蚧(Hemiberlesia pitysophila Takagi)受冻死亡者身体上出现深色的斑带.在同一时间处理下处理温度与松突圆蚧存活率存在明显的 S 形曲线关系 sin~(-1)(2S-1)=A+Bt.3～24小时的冷冻试验可得处理时间与致死中量的回归方程 Lt_(50)=-8.5165+2.6043lnh.-10℃下24小时,99%以上死亡.预测松突圆蚧潜在的分布北界为北纬32～33°之间.     

浙江武义森林植被区系的地理成分研究

提供了浙江武义的森林植被区系。该区系具有丰富的植物种类、古老植物和珍稀濒危植物,温带－温亚热带成分占优势,地理成分与世界各地植物区系有广泛的联系。该区系有１４个类型的成分,东亚成分、泛热带成分及东亚－北美间断成分具有较多的属,而地中海、西亚及中亚成分、温带亚洲成分及世界成分具有较少的属。     

中国橡胶种植北界

基于中国橡胶的地理分布信息及其相应的气候资料,结合最大熵模型,明确了影响中国橡胶种植的5个主导气候因子,即最冷月平均温度、极端最低温度平均值、月平均温度≥18℃月份、年平均气温和年平均降水量。在此基础上,给出了80%气候保证率下中国橡胶树稳产高产的种植北界,该北界准确覆盖了目前中国橡胶主产区的实际种植区域。研究结果可为中国橡胶种植优势区域布局规划及防灾减灾提供科学决策依据。     

中国大陆北热带及亚热带地区樟科、壳斗科物种多样性及其生物地理格局分析

以中国大陆北热带及亚热带地区优势科樟科、壳斗科植物为研究对象,利用专著发表大量的样方数据和物种分布数据,分析樟科、壳斗科与群落构建的关系、它们各大属的地理分布格局,探讨影响其分布的可能历史原因。结果表明:中国大陆北热带及亚热带地区森林乔木层优势科为樟科、壳斗科、山茶科、杜鹃花科。樟科、壳斗科物种丰富度均与其所在群落的物种丰富度呈现一定的正相关,樟科对群落构建的贡献较大。樟科、壳斗科植物种的空间多样性分布中心均出现在我国亚热带中部偏南地区。樟科的厚壳桂属、琼楠属以及壳斗科的锥属物种多样性分布中心主要在南亚热带及北热带区域,以广西、云南省份的南部为主。樟科的樟属、新木姜子属、润楠属、木姜子属及壳斗科的柯属、青冈属主要分布在我国大陆北热带及亚热带中部偏南的地区,其多样性分布中心与樟科、壳斗科科水平的物种多样性分布中心极为相似。樟科的山胡椒属、楠属、黄肉楠属,壳斗科的栎属主要分布在研究区域中部以西的地区。研究结果佐证物种的生态学特性以及生物地理学历史综合作用导致目前樟科和壳斗科植物的生物多样性分布格局。     

中国泥盆纪珊瑚的生物地理及其群落生态

中国泥盆纪可识别出６个珊瑚生物地理区：南天山区、古特提斯区、华南区、华北北缘区、准噶尔－兴安区和保山区。其中,前４４个区均处于当时赤道两侧的低纬度地区,属于老世界大区;而后２个区则可能分别位于北温带和南温带区域内,不在老世界大区范围内。中国泥盆纪珊瑚群大多数都是生活在温暖浅海近南栅上富氧透光带中的群落,其分异度,丰度和密度各有不同,大致属于海浪底栖生物组合ＢＡ３－ＢＡ４;但也有的生活在远岸大陆斜坡     

“田中线”及其在生物地理上的运用问题

日本学者根据对柑桔种系的地理分布设想了一条从云南西北部(28°N,98°E)向东南部延伸到越南北部东京湾(大约18°45’N或19°N、108°E)的分界线,将其命名为"柑桔分布的田中线",简称"田中线"。后来它被认为在区分中国-日本植物分布属与中国-喜马拉雅分布属上具有生物地理意义,并与一些兰科植物属的分布相结合提出了"田中-楷永线",建议将它作为一条划分东亚植物区系东部的中国-日本植物亚区与西部的中国-喜马拉雅植物亚区的区系线。一些研究显示该线对一些物种的种群分化和谱系地理有意义,但主要是气候和地貌引起的环境梯度变化,不支持它是一条古老的生物地理分界线。另外,这条"柑桔分布的田中线"本身,未得到柑桔属内及其近缘属的系统发育关系研究的支持。云南植物区系的生物地理分异明显,但与"田中线"无显著联系,在云南植物区系分区上,"田中线"也基本无意义。云南复杂的地质历史、多样的气候和地貌,影响了植物区系的生物地理分异,用这条设想的从云南西北部向东南部延伸的斜直线作为一条生物地理界线,与最近的研究具有不相符性。     

中国植物区系地理的文献计量分析

本文采用计量分析方法研究了中国植物区系地理的文献并且初步分析了文献内容的构成。最后,提出了有助于发展中国植物区系地理研究的六点建议。     

论中国海南岛的生物地理起源

当前海南岛植物区系以热带分布的科和属占绝对优势,在属的地理成分上热带亚洲分布属的比例最高,显示出它是一个热带性质的植物区系,并具有热带亚洲亲缘。在海南植物区系中,仅有7个特有属和约10%的特有种,极低的特有性显示了它具有明显的大陆起源特征。通过比较研究发现,中国海南植物区系与越南植物区系关系最密切,其次是广西植物区系。在哺乳动物上,也显示出与植物区系类似的生物地理格局,中国海南与越南的联系最密切。古植物学研究揭示海南岛在始新世时曾具有亚热带性质的植物区系和亚热带气候,处在比现今更北的位置。古地磁学研究揭示在中生代时期海南岛连接着越南和中国广西,处于比现在高5~6个纬度的位置。综合各方面的研究,我们从生物地理的角度提出中国海南岛在始新世时曾连接着越南和中国广西,后来发生了向东南移动和旋转,最终到达现在的位置。     

Observations on the Flora and Vegetation of Taibai Shan,Qinling Mountain Range,Southern Shaanxi,China

Taibai Shan Mountain is generally known as “The highest mountain in the Qinling Mountain Range.” It is situated between 33°40' and 34°10'N latitude and 107°19' and 107°58'E longitude in southern Shaanxi Province. The area is deeply cut on all sides by four, V-shaped valleys, which gives the landscape a steep topography. The highest peak is about 3767 m above sea level, and the relative elevation of the whole Taibai Mountain area ranges from 1000 to 2200 m. Five chief soil types have been described in this region and are vertically distributed as follows: 1) Ochric castanozom, below 1000 m; 2) Brown forest soil, 1000-1500 m; 3) Podzolic brown earth, 1500-2800 m; 4) Podzolic soil, 2800-3000 m; 5) Alpine meadow soil, above 3000 m. Fu (1982) in an analysis of the Taibai Shan mountain area's summer climate, and in comparing temperatures on the north and south sides, described higher maximum temperatures at low elevations on the south, but lower temperatures at high elevations on the north. Rainfall is much higher on the south. The rugged topography of the Taibai Shan Range still preserves some tracts of natural er semi-natural vegetation at higher elevations. Our vegetational survey was confined to localities above 1300 m, whereas collecting specimens for documenting the flora extended over the whole area from the foothills ro the peak. On the basic of these floristic, vegetational and environmental studies in the Taibai Shan Mountain we are now able to draw some conclusions on the nature and relationships of the interesting flora and vegetation, and to discuss to some extent the phytogeography of an important segment of the Chinese flora. 1. Survey of large families of angiosperms. There are twenty large families of flowering plants in the Taibai Shan Mountain of Qinling Range (Table 1). The largest families are the Asteraceae (175 species), Poaceae (123 species) and Rosaceae (124 species). The Rosaceae is a major family in this region, and species in the family are characteristic members of the flora and vegetation of the temperate zone in China. Both Asteraceae and Poaceae are also frequently found in forests and elsewhere in this region. There are three families with 60 to 90 species; three families with 50-60 species; three families with 40-50 species and eight families with 20-40 species. These families combined contain 1186 species, including 655 endemic to China, making up 66.6% of the total flora, and play an important role in shaping the characteristics of the forests of the Taibai Shan Mountain. All these large families are temperate in nature. 2. Relationships of the Taibai Shan flora with others The Taibai Shan Mountain of the Qinling Range is very rich in genera (657) and species (1782) of flowering plants. Based on their geographical distribution, the genera of flowering plants in the Taibai Shan Mountain are classified into 15 distribution types (Table 2). In accordance with our analysis of all of the distribution types it is reasonable to conclude that: among the native genera in the flora of Taibai Shan,130 containing 242 species (22.1%) are tropical, 436 containing 1186 species (73.8%) are temperate and 24 (4.1%) are endemic to China. From these figures the flora of Taibai Shan can be thought of as composed of temperate elements. To determine the floristic affinities of the area with others within China, nine mountain regions were selected for a comparison (Table 5). Based on the worldwide distribution of genera in the ten mountain regions, 15 distribution patterns can be recognized (Table 4). A comparison of the similarities among the ten mountainous regions in China, based on the distribution of genera, shows that the floristic affinities of the Taibai Shan are first with the Daqing Shan in northern China and the Shennongjia region in central China, and secondly with the Jinfo shan, the Fanjing Shan, the Yulongxue Shah and the Nanjiabawa Mountain in southwestern China. 3. The structure and vertical distribution of communities in the Taibai Shan Mountain. The diagrammatic structures of the chief plant communities in the Taibai Shan Mountain are given in Fig. 8.1-8.6. All of the dominant species, except Betula utilis, are endemic to China. The distributional areas of some of dominant species overlap in the Qinling Mountain Range (Fig. 2 and 3). On the basis of floristic composition and the coefficients of similarity between narrow belts of vegetation (Tables 7 and 8), the vertical distributions of the plant communities on different slopes are shown as follows: Northern slope: 1) Quercus aliena var. acutiserrata forests (below 1800 m); 2) Quercus liaotungensis forests (1800-2200 m); 3) Betula albo-sinensis forests (2200-2800 m); 4) Abies fargesii forests (2800-3000 m); 5) L.arix chinensis forests (3000-3400 m); and 6) subalpine scrub (above 3400 m). Southern slope: 1) Quercus variabilis forests (below 1500m); 2) Ouercus aliena var. acutiserrata forests (1500-2000 m); 3) Betula utilis forests (2000-2500 m); 4) Abies fargesii forests (2500-3000 m); 5) Larix chinensis forests (3000-3400 m); and 6). subalpine scrub (above 3400 m). 4. Species diversity along gradients of elevation. In terrestrial habitats, variation in species diversity along gradients of elevation and available soil moisture are, generally speaking, almost as striking as latitudinal variation. Variation in the diversity of species of trees, shrubs and herbs with changes in elevation in the Taibai Shan Mountain of the Qinling Range is discussed. The number of tree species declines with increasing elevation, but the diversity of shrubs, and especially the herbaceous species, reaches the greatest richness at intermediate elevations in the Taibai Shan Mountain (Fig. 9). Whittaker (1960, 1977) has reported a similar pattern on temperate mountains in the United States. 5. Analysis of life-form spectra. A comparison of life-form spectra in the vegetation between the southern and northern slopes shows that the five principal classes of life-forms on the southern slope (Fig. 8. b) are very similar to those on the northern slope (Fig. 8. c). The correlation of life-form spectrum with altitude (Table 9) reveals a significant trend; a steady decrease of phanerophytes, but conversely increase of therophytes with altitude. In Table 10 is a series of spectra for certain community types in different regions. Here we see that the temperate deciduous broad-leaved forests of the Taibai Shan Mountains, Changbai Shan mountains, Beijing area in northern China and in the Appalachian region in eastern North America have very similar life-form spectra. In another case the evergreen broad-leaved forests of the Jinyuy Shan and Wuyanling mountains in southeastern China have strikingly similar life-form spectra. 6. Diels (1901, 1905) was the first botanist to recognize the Qinling Mountain Range as a botanical boundary between southern and northern China, a division also recognized by geographers. Since the 1960's most Chinese botanists have believed that the Qinling Mountain Range, together with Huai He River, forms a natural botanical divide between subtropical and temperate regions. From a floristic and phytogeographical viewpoint, however, it seems that this opinion is in need of reconsideration. As mentioned above, an analysis of genera and species pretty clearly indicates that the flora of the Taibai Shan Mountains is temperate in composition. Furthermore, all of the plant communities in this region are deciduous broad leaved forests or subalpine coniferous forests. On the other hand, the annual accumulated temperature, the average temperature in the coldest month and the annual mean temperature of the whole Tabai Shan Mountains exhibit the characteristics of a temperate climate. Thus it is clear that the Qinling mountain range, together with the Huai He River, can be credited as being a natural botanical divide between the warm temperate and temperate regions ofChina. 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Twenty years of research on community composition and species distribution of arbuscular mycorrhizal fungi in China: a review

The biodiversity and distribution of arbuscular mycorrhizal fungi (AMF) in different ecosystems and plant communities in China has received increasing interest over the past decades. This has led to a steady increase in the number of scientific papers published on this topic. Studies have surveyed AMF-colonizing rhizospheres of most families of angiosperms, bryophytes, pteridophytes, and gymnosperms. China has about 30,000 plant species (one eighth of the plant species worldwide). A total of 104 AMF species within nine genera, including 12 new species, have been reported in environments such as croplands, grasslands, forests, and numerous disturbed environments. In this paper, we review data published over the past 20 years on AMF community composition and species distribution, the mycorrhizal status of plants, AMF spore communities in different habitats, and germplasm collections in China. Possible future trends in the study of the biodiversity of AMF are also briefly discussed. In particular, the aim of our review is to make some of the recent work published in the Chinese literature accessible to a wider international audience.     

华南三省(区)2001—2020年植被物候时空变化

为深入了解气候变化对我国热带亚热带季风区植被物候的影响,该文基于2001—2020年MODIS EVI时序数据,采用Double Logistic法和阈值法提取华南三省(区)植被物候参数,分析了华南三省(区)植被物候的时空变化特征。结果表明, 研究区植被返青期主要集中在第90~105天,枯黄期在第320~335天,生长季在第220~235天。20年来植被返青期推迟,枯黄期基本不变,生长季缩短。在空间分布上,返青期在两广地区自西向东、自北向南逐渐推迟,海南则自东北向西南逐渐推迟;枯黄期表现为在两广中部晚、周边早,在海南中部早、周边晚的分布特征;生长季在两广地区整体自西向东逐渐缩短,在海南则自西南向东北逐渐延长。随着海拔增高,不同地区和不同植被的返青期差异较大,且波动性较大,而枯黄期先推迟后提前,生长季先延长后缩短。这揭示了气候变暖背景下华南三省(区)植被物候的变化特征,对更全面认识我国南方植被对气候变暖的响应有指导意义。     

Levels of the upper forest boundary in northern Asia

On the Ural range the elevation of upper timberline changes at grade 71 m per degree of latitude in linear regression. Much lengthy cross-section—for the semi-arid regions of middle Siberia and adjacent Kazakhstan, and for the regions of eastern Siberia dominated by larch forests—exhibit parabolic regression of timberline levels upon geographic latitude. The longitudinal gradient of timberlines presumably depends on radiation balance related with the amount of precipitation. The arctic boundary of taiga in eastern Europe and Siberia lies mostly on average latitude 69° 36 E. It correlates with mean July temperature 11.2 °C, or with duration of the growing season 128 days with stable temperature of air exceeding 0°C which amounts to 876°. Daily temperatures exceeding 5° and especially 10 °C are seemingly less influential there. The value of 11.2 °C deviates by about 1 °C from the value of above 10 °C for three summer month reported by Langlet 1935, which shows the close environmental control regulating the northern and upper boundary of the northern, mostly coniferous forest on the northern hemisphere.     

Conditions for the development of the Pinus pumila zone of Hokkaido,northern Japan

The development of the Pinus pumila zone of Hokkaido, northern Japan is discussed on the basis of an examination of the Warmth Index (WI). The Pinus pumila zone is developed on deforested areas in the boreal subalpine belt, and is characterized by strong wind and heavy snow accumulation in winter, and by the presence of rocky fields. It is concluded that in Japan, including Hokkaido, this high mountain zone generally is intrazonal, belonging mainly to the subalpine belt, and that such zones are not common in Europe and North America. Its formation is due mainly to present-day wind, snow and substrate conditions and partly to conditions prevailing during the glacial period.     

中国北方农牧交错带优化生态-生产范式

中国北方农牧交错带具有生态、生产双重功能,在国民经济发展中具有重要战略地位。构建优化生态生产范式是对其进行科学管理的一种有效方式。优化生态-生产范式是应用生态经济学原理与系统科学方法,以生态恢复与重建为目标,以多用途资源利用和景观生态设计为核心,以生物-自然和社会-经济综合分析为基础,结合现代科学成果和传统农牧业技术的精华而建立起来的结构优化、功能持续、经济可行的农林牧复合经营系统的范例。文章对优化生态生产范式的配置以及配套技术的研究现状进行了综述,提出在构建优化生态生产范式的过程中应当遵守规模的发展与土地承载能力相适应的原则、限制因子原则、景观异质性与尺度的原则以及生态、经济和社会效益统一的原则。针对目前范式研究中着重经济效益、研究尺度单一、缺乏学科间的综合和集成、效益评价体系不完善等一些问题,指出了今后范式研究的趋势,认为今后的研究应重视基础理论和应用技术的研究、对现有范式进行调整和优化、建立统一的评价体系、量化范式适宜程度和优化程度。在基础研究方面应主要集中在主要的农业生态系统对不同人为干扰响应的形式和实质,研究确定一系列重要的生态经济阈值;应用技术方面应注重于调整产业结构,积极发展高科技产业,提高产投比。对范式实施后的各项生态经济指标进行动态监测,从而对范式进行适时调整与优化。对不同范式取得的效益进行横向的、定量的研究,选择出最优的范式。同时,学科间的融入将成为范式研究中的又一特点。     

Acceleration of vegetation succession on eroded land by reforestation in a subtropical zone

Based on field investigations in the East River basin in Guangdong Province, south China, the processes of vegetation development and vegetation succession on bare slopes with high erosion rates are studied. Different reforestation measures have been applied to the slopes, which have resulted in very different processes of vegetation development and succession. On an experimental plot with burned forest but surviving roots, the vegetation restored naturally and quickly because there was little soil erosion. However, in the plots suffering from long-term severe soil erosion, natural vegetation recovery on these barren slopes is very slow. After 26 years, a barren slope has only been partly colonized by poorly developed vegetation composed of heliophilous herbages and scattered shrubs. On the other hand, plantation of some selected wood species on the slope land has dramatically accelerated the vegetation recovery and succession. The plots were reforested with plantation of Acacia auriculiformis in the early 1980s. Twelve years later, the vegetation cover of the artificial forests reached 90% and an understory vegetation community consisting of local species had naturally developed. Reforestation with suitable strategies may control erosion and greatly accelerate vegetation succession in the eroded slope land in the subtropical zones.     

云南热带雨林:特征、生物地理起源与演化北大核心CSCD

云南热带雨林具有与东南亚低地热带雨林类似的群落结构、生态外貌特征和物种多样性,是亚洲热带雨林的一个类型。它的植物区系组成中有90%的属和多于80%的种为热带分布成分,其中约40%的属和70%的种为热带亚洲分布型,它含属种较多的优势科和在群落中重要值较大的科也与亚洲热带雨林相似,是亚洲热带雨林和植物区系的热带北缘类型。云南西南部、南部与东南部的热带雨林在群落结构和生态外貌上类似,但在南部与东南部之间有明显的植物区系分异,它们经历了不同的起源背景和演化历程。云南的热带雨林在很大程度上由西南季风维持。喜马拉雅隆升导致西南季风气候形成和加强,在云南热带局部地区产生了湿润气候,发育了热带雨林植被。现在的云南热带雨林里或其分布地区有落叶物种或热带落叶林存在,这不仅是季节性气候的影响,推测在晚第三纪或第四纪更新世云南热带地区曾经历了干旱气候。云南热带雨林的分布主要受制于局部生境,并非地区性气候条件。