云南亚热带南部孢粉空间组合特征及其与环境分异的关系

以云南亚热带南部野外调研孢粉资料为基础,分析了7个样地的35个表土样品以及28个剖面样品孢粉组合的空间分异特征.结果发现:(1)表土孢粉无论是在科属种类、数量及优势科属还是在科属植物区系上,哀牢山山脉东西两侧的样地均具有较大的差异.孢粉科属种类和数量方面,哀牢山西侧样地要较东部丰富;优势科属方面,哀牢山山脉西侧植物群落的优势科属不明显,且较东部要复杂,而东部地区植物群落的优势科属则较为集中和突出;植物区系分布方面,世界广布、泛热带、热带亚洲至热带非洲以及北温带分布等4个植物区系,其数量和所占比例东西差异都很大.(2)剖面孢粉的分析结果显示,其空间变化趋势与表土孢粉基本一致,同样反映了孢粉组合的东西空间差异.(3)孢粉组合的空间组合与区域的地形、气候分异特征有关.纵向排列的山系对大气环流的"阻隔"作用,以及哀牢山东西侧不同的季风环流系统导致的水热组合条件的差异是造成孢粉组合空间分异格局的主要原因.云南亚热带南部孢粉空间组合反映了区内自然环境的区域差异.     

哀牢山东、西两侧植被NDVI指数和植被类型与主要环境因子的相关性分析

以哀牢山南段为研究区域,利用遥感植被信息、气候数据以及DEM基础资料,对哀牢山东、西两侧植被的NDVI指数和不同植被类型与主要环境因子的相关性进行分析.研究结果表明,哀牢山东、西两侧山地植被的NDVI指数与海拔的相关性最大,与气温、降水量和太阳总辐射量也有一定的相关性,与坡度和坡向的相关性最小.哀牢山东、西两侧的植被NDVI指数都与年均最低温和年均最高温呈负相关,且东侧区域的相关性大于西侧,表明极值气温对东侧区域的植被影响更大.在哀牢山东、西两侧研究区内共有9种植被类型,以稀树灌木草丛为主要植被类型,分别占各自区域面积的40.59%和35.82%;西侧森林植被中常绿部分所占比重高于东侧.相对于东侧区域,哀牢山西侧区域的海拔偏高、气温偏低、降水量较多、太阳总辐射量较大、植被覆盖度较高.总之,基于地形对水热因子空间再分配的影响作用,哀牢山山脉两侧的气候和植被特征具有较大差异.     

探访哀牢髭蟾

髭蟾在我国有5种。实事求是地讲,以前我对髭蟾一无所知,我相信一般人对它们也缺乏了解。在5种髭蟾中,有一种直到1984年才被发现,那就是哀牢髭蟾。哀牢髭蟾仅分布于云南滇中哀牢山和无量山地区,无量山国家级自然保护区是该物种分布的最北端。哀牢髭蟾的模式产地在云南景东徐家坝,哀牢山是科学家们首次发现它的地方,哀     

云南哀牢山国家级自然保护区药用蕨类植物资源

报道哀牢山国家级自然保护区药用蕨类植物资源。通过两年多的野外考察（标本存于PYU）和查阅原标本文献记载（PYU和KUN）,首次报道了哀牢山蕨类区系有蕨类植物48科,118属,446种（包括变种和变型）。哀牢山蕨类区系是亚热带性质的区系。哀牢山国家级自然保护区可供经济利用的蕨类超过300余种,其中,药用蕨类植物有45科76属178种,占中国药用蕨类植物科属种的比例分别为91．8％、65．5％和41．1％。最后讨论了哀牢山药用蕨类植物资源的保护与开发利用。     

高黎贡山北段东西坡种子植物区系的比较研究

高黎贡山北段的东西坡由于在降雨量和热量分配等方面存在着显著的差异,致使东西坡在植物的种类、组成及区系特征等方面表现出明显的差异.东坡记载野生种子植物152科,580属,1475种及192变种(亚种),西坡记载野生种子植物162科,659属,1804种及186变种(亚种).东西坡种子植物科、属、种的对比分析表明:1)东西坡现代种子植物区系具有相同的历史渊源,但其区系联系减弱了,东西坡区系相似性程度,依科、属、种的顺序依次递减;2)西坡现代种子植物区系比东坡具有更为深刻的热带起源烙印.就科、属、种三个水平来说,东坡的热带成分低于西坡,温带成分高于西坡.许多典型的泛热带大科在西坡比东坡有着更为丰富的种类,其中有些泛热带科分子在东坡缺乏分布,而在西坡找到了合适的驻留之地;3)西坡现代种子植物区系与东喜马拉雅植物区系的联系比东坡紧密,而东坡与高黎贡山以东的区系联系比西坡密切,由于高黎贡山山脉的阻隔,近代植物物种的东西坡交流发生了障碍;4)西坡生态地理环境比东坡更有利于物种的生存、繁衍和分化,它既是古老成分的避难所,又是孕育新生成分的摇篮.     

紫椴、水曲柳人工幼林霜冻发生与控制研究

采用垂直梯度观测与样地调查相结合的方法,对紫椴和水曲柳人工幼林最低温度变化、物候及霜冻程度进行了系统研究和分析,同时进行了防止紫椴晚霜冻田间试验.结果表明,紫椴的物候较水曲柳晚;受逆温现象的影响,不同坡向和坡位的紫椴和水曲柳物候变化表现出特殊的规律性,西坡芽苞开放时间较东坡早,芽苞开放随坡位的上升而提前,并以坡上最早;晚霜的发生是早春季节降温过程与该阶段林木物候变化动态吻合的结果;通过立地选择可以有效地控制霜冻,该地区坡下特别是东坡的坡下不适合营造紫椴和水曲柳人工林;化学物质和生物遮荫可以推迟紫椴萌动,进而防止霜冻;混交林对防止霜冻具有明显效果,无论是霜冻指数还是各受害等级的株数比例均低于纯林.     

山坡退化林地林木生长对微地形人工干预的响应

为探究水土保持微地形人工干预措施(等高反坡阶)对坡面退化林地林木生长的影响,在昆明市松华坝水源区内选取典型山坡退化林地,通过动态观测和对比分析不同样地林木胸径、树高、新枝生长量及样地叶面积指数(LAI)的变化差异,再结合土壤水分有效性分析以探讨差异原因.结果表明:等高反坡阶样地云南松胸径和树高的最大值和均值均大于对照样地(CK),退化林群落中小径阶和低矮的植株占更大比例,表明等高反坡阶样地中优势木新生植株和退化严重植株的生长潜力得到激发,不同样地云南松植株新枝平均枝长和枝径的年变化差异率达到了72.4%和39.1%.等高反坡阶样地云南松植株新枝生长量和样地LAI的变化及新枝生长的速度大于CK.土壤含水率和新枝生长量与LAI均呈显著相关,对水分有效性分析后得到等高反坡阶样地易效水比例(64.2%)整体高于CK(54.7%),5月至9月雨季中,等高反坡阶样地易效水存在时间更长,这有利于林木的生长,进而改变退化林地植物群落结构.     

云南哀牢山国家级自然保护区蕨类植物生态地理研究

报道了哀牢山国家级自然保护区蕨类区系有蕨类植物48科、118属、446种(包括变种和变型)。从蕨类植物的垂直分布、东西分布和生态类型的划分等几个方面对哀牢山国家级自然保护区蕨类植物生态进行探讨并得出以下结论:(1)在海拔分布上,蕨类植物有着与不同植被相关的生态适应性,2000~2800 m的中山湿性常绿阔叶林和山顶苔藓矮林地带蕨类植物种类最为丰富,附生蕨类植物占到了该海拔地带蕨类植物总种数的28.5%;(2)东坡有蕨类植物387种,西坡则只有355种,东西坡共有种达295种;(3)哀牢山国家级自然保护区蕨类植物可划分为16个生态类型,本区明显地以阴生植物、亚高温植物和中生植物居多,附生植物种类所占比例大,旱生植物和石生植物种类少等为主要生态特征。哀牢山国家级自然保护区蕨类植物的温度生态类型以亚热带植物种类为主,温带植物和寒温带植物少。     

南海北部早第三纪涠洲组孢粉组合

本文是北部湾东北部、雷州半岛、涠洲岛及海南岛北部十几口钻井中涠洲组 孢粉工作的总结。在涠洲组中共见113种孢粉类型,其中大部分为欧亚及北美 第三纪、尤其是渐新世孢粉区系成分,同时也出现加里曼丹岛渐新世-早中新世 区系的一些重要分子。这表明沉积时期本地区与加里曼丹岛有陆地相通或在地 理位置上较今日为近,植物能相互迁移。 印度第三纪孢粉区系与涠洲组区系相 似性拉少,仅出现少数相似类型(水蕨孢子、松科花粉),说明虽然自印度次大陆 与欧亚大陆相遇后,这两地区的植物有了相互迁移的可能,但是直到渐新世,这 种迁移的规模还是很有限的,迁移到印度的植物所产生孢粉类型在印度发展的 高峰可能较欧亚大陆为晚。 从孢粉所反映的生态条件看,陆生及淡水植物多,而海产植物(如红树林)及 藻类很少。这说明当时北部湾可能为陆地,与雷州半岛等地连成一个内陆凹陷。 大量温带及山地针叶植物花粉及少量热带低地植物花粉的出现表明本地区附近 曾有大面积山地。 从孢粉组合上看,涠洲组形成的时代为渐新世。     

云南哀牢山国家级自然保护区蕨类植物区系地理研究

通过野外调查和资料整理分析,哀牢山国家级自然保护区共有蕨类植物48科,118属,446种(包括变种和变型)。优势科为鳞毛蕨科、水龙骨科和蹄盖蕨科,优势属为耳蕨属、蹄盖蕨属、鳞毛蕨属和卷柏属。区系分析结果表明:该蕨类区系是亚热带性质的区系;热带亚洲成分随着海拔的升高,比例逐渐降低,而中国-喜马拉雅成分随着海拔的升高逐渐增加;地理成分的东西坡差异不明显;该蕨类区系与喜马拉雅地区和热带亚洲的关系较密切,而与日本的关系较疏远;该蕨类区系具有较丰富的中国特有成分;哀牢山明显处于滇西北、滇东南这两大中国特有多样性中心之间,成为联系的纽带。     

云南热带季雨林及其与热带雨林植被的比较

在中国植物学文献中, 对热带季雨林的解释和运用是不一致的, 特别是易于把季雨林与热带雨林相混淆。季雨林是在具有明显干、湿季变化的热带季风气候下发育的一种热带落叶森林植被, 是介于热带雨林与热带稀树草原(savanna)之间的一个植被类型。云南的热带季雨林在分布生境、生态外貌特征、植物种类组成和地理成分构成上, 均与热带雨林有明显区别, 季雨林主要分布在海拔1 000 m以下的几大河流开阔河段两岸和河谷盆地, 其群落结构相对简单, 乔木一般仅有1至2层, 上层树种在干季落叶或上层及下层树种在干季都落叶; 在生活型组成上, 季雨林的木质藤本相对较少, 大高位芽植物及地上芽植物很少, 但地面芽植物很丰富, 地下芽植物和一年生植物也相对丰富; 在叶级和叶型特征上, 季雨林植物的小叶和复叶比例相对较高, 分别占到24%和44%; 在植物区系地理成分构成上, 季雨林的热带分布属合计也占绝对优势, 但以泛热带分布属的比例相对较高, 约占到总属数的30%, 热带亚洲至热带非洲分布属的比例也较高, 约占总属数的12%。季雨林的地理成分更为多样性, 起源与发展历史也更复杂和古老。     

哀牢山常绿阔叶林鸟类群落初步分析

常绿阔叶林是云南境内重要的自然资源,也是我国亚热带地区最主要的原生植被类型。是森林生态系统的主要研究对象之一。鸟类是森林生态系统的重要组分,为便于自然保护区的规划、管理及对鸟类资源的保护和研究,本文报道有关哀牢山常绿阔叶林鸟类群落动态。 自然环境和工作概况     

Population and distribution of western black crested gibbon (Nomascus concolor) at Ailao Mountain, Xinping, Yunnan

The western black crested gibbon (Nomascus concolor) is mainly distributed in Yunnan, China. Ailao Mountain is located in central Yunnan and divided into three prefectures and six counties. This mountain forms the principle distribution range for western black crested gibbon; however, there are no published data on the gibbon population inhabiting the Xinping administrative. Take the interview results conducted in 2007 and 2009 with local people as the reference, this study conducted an extensive field survey covering all possible habitats from November 2009 to January 2010 using call surveys. Among the one hundred and twenty-four gibbon groups which were confirmed across the Ailao Mountain, the largest known population of western black crested gibbons yet, 85 groups inhabit the national nature reserve and adjacent national forest, 30 groups inhabit the provincial nature reserve and nine groups inhabit the collective forest located outside the reserve and national forest. We found that the western black crested gibbons here have a patchy distribution pattern and occur at higher densities in certain areas. Moreover, the population distribution density and elevation gradient distribution decline from north to south. The results also demonstrated the importance of Ailao Mountain in the western black crested gibbon protection.     

Late Pliocene vegetation and climate of Zhangcun region,Shanxi, North China

To understand the Neogene climatic changes in eastern Asia and evaluate the intercontinental climatic differences, we have quantitatively reconstructed the vegetation successions and climatic changes in the late Pliocene Zhangcun area based on the palynological data and explored the regional climatic differences between central Europe and eastern Asia. The late Pliocene palynological assemblage of Zhangcun, Shanxi was composed of 63 palynomorphs, belonging to 50 families, covering angiosperms (90.2%), gymnosperms (9.7%), ferns (0.09%), and other elements (0.02%). Four periods of vegetation succession over time were recognized. In period 1, a needle‐ and broad‐leaved mixed forest prevailed with a cool and dry climate. Period 2 was characterized by an expansion of forest with a warmer and wetter climate. The number of conifers increased and that of herbs decreased in period 3, and the climate became cool and dry. In period 4, the forest was dominated by conifers and reflecting a cooler climate. The data of seven climatic parameters in general and four periods estimated by the Coexistence Approach suggested that (1) The late Pliocene temperatures and precipitations were higher than today. (2) The Neogene climate of both Central Europe and North China exhibited a general cooling and drying trend although the mean annual temperature dropped by ca. 1 °C in North China, vs. ca. 7 °C in Central Europe from the middle Miocene to the late Pliocene. (3) The decline of the mean maximum monthly precipitation might signal a weakening of the summer monsoon. (4) The decline of both the mean coldest monthly temperature and the mean minimum monthly precipitation might be linked to the strengthening of the winter monsoon in eastern Asia. (5) The rapid uplift of the Tibetan Plateau strengthened the climatic cooling and drying during the late Pliocene of the Zhangcun region.     

Effects of monsoon on distribution patterns of tropical plants in Asia

Comparing with other regions, Asia is mostly dominated by the monsoon climate and tropical plants can be found at the furthest places away from the equator. Understanding the role of monsoon in the dispersal and evolution of tropical plants is helpful for exploring the distribution patterns of vegetation and mechanisms underlying the origin and maintenance of biodiversity in Asia. In summer, there are three types of monsoon in Asia, i.e. East Asia Monsoon, South Asia Monsoon, North-west Pacific Ocean Monsoon. The summer monsoon climate in Asia originated at about 40 Ma, when the early angiosperm evolved and started its diversification in Southeast Asia and South China. It suggested that the monsoon may facilitate the quick speciation and spread of early angiosperm. Monsoon climate facilitates the northward spread of Asia’s tropical plants and some tropical plants can be found even at Yarlung Zangbo River and the boundaries of Guizhou-Guangxi-Yunnan. Such effetcs largely change distribution patterns of zonal vegetation and even causes local vegetation types in some places with unusual topography such as tropical seasonal rainforests, monsoon rainforests, savanna and grassland along dry-hot valley in Southwest China, coastal savanna in West Hainan Island. The three summer monsoons interact at Southwest China and Indo-China Peninsula and these regions are dominated by limestone landscapes and high mountains with big rivers. Some Asia-endemic tropical taxa even formed a diversification and endemism center at this region, which may be a reason for the formation and maintenance of Indo-Burma biodiversity hotspots with global warming, the monsoon may further promote the northward spread of tropical plants and may have fundamental effects on biodiversity and flora evolution in South China.     

云南哀牢山地区蕨类植物区系的垂直分布格局

根据大尺度的物种分布信息,利用聚类分析和数理统计的方法分析了云南哀牢山蕨类植物区系的垂直分布格局。研究结果表明,随着海拔的升高,热带区系成分所占比重呈显著递减趋势,而温带区系成分所占比重呈明显递增趋势。在整个海拔梯度上,东亚分布和热带亚洲分布成分始终占主导地位。区系过渡性随着海拔的升高呈先增强后减弱的单峰分布格局,平衡点出现于海拔1700 m左右。基于区系成分比重的聚类分析表明,在海拔1300 m,1900 m和2600 m左右,将海拔梯度上的蕨类植物分为4组,这与各海拔段内的物种组成和区系成分性质是一致的。     

哀牢山和猫儿山中山常绿和落叶阔叶树光合特性对季节温度变化的响应

研究调查了云南哀牢山中山常绿阔叶林和广西猫儿山中山落叶水青冈林中共生的常绿和落叶阔叶树光合特性在2005年的季节变化,探讨了两地温度气候差异对植物优势度的影响。在夏季,同一生境下的常绿植物和落叶植物之间以及两个生境树种之间的光合速率没有显著差别。当温度下降时,两个生境内的常绿和落叶植物的光合速率都下降,这与气孔的部分关闭和光系统Ⅱ活性的下降有显著的关系。气孔的部分关闭有利于减少水分蒸腾损失,但落叶树气孔关闭程度明显高于常绿植物而且无法避免严重的光抑制。常绿植物通过气孔调节来提高光合水分利用效率和通过光系统Ⅱ活性调节来降低光合机构的损伤来维持叶片四季常绿,但是猫儿山中山森林冬季低温严重损害气孔和光系统Ⅱ的功能而使常绿植物生长受到严重制约并限制其在群落中成为优势种,与之相反,哀牢山中山森林冬季相对暖和导致常绿植物能积累更多的光合产物并促进其在群落中形成优势。     

Geochemical compositions of core sediments in eastern China: Implication for Late Cenozoic palaeoenvironmental changes

Three deep drill holes with depth exceeding 300 m were collected from eastern China for geochemical study in order to reconstruct Late Cenozoic palaeoenvironmental changes. The Late Cenozoic strata in eastern China are predominantly composed of lacustrine, fluvial and littoral sediments. Degrees of chemical weathering during the Late Cenozoic were estimated by using geochemical proxies including CaCO₃ contents, chemical index of alteration and Al₂O₃-CaO-(Na₂O + K₂O) diagrams. The results show that chemical weathering was intense in eastern China in the Late Neogene, and progressively weakened during the Quaternary, albeit with amplified fluctuations. Although the palaeoclimatic conditions reconstructed from the drill holes in eastern China are generally comparable with those records from the loess-palaeosol sequences, red clay, and deep-sea sediments in East Asia, they changed asynchronously in north-central and southeast China during the Neogene. The Late Neogene palaeoclimate was overall warmer in southeast China than on the North China Plain except for some extreme cooling periods in the Late Pleistocene. In contrast, the North China Plain experienced moderate to weak chemical weathering with the intensification of East Asian winter monsoon activities during the Late Quaternary. Regional differentiation of palaeoclimatic variability since the Pliocene in eastern China is comparable with today's climate regimes in the Changjiang and Huanghe drainage basins but with different intensities, suggesting different impacts of the East Asian palaeomonsoon during the Late Cenozoic.     

Changing patterns of the East Asian monsoon drive shifts in migration and abundance of a globally important rice pest

Numerous insects including pests and beneficial species undertake windborne migrations over hundreds of kilometers. In East Asia, climate-induced changes in large-scale atmospheric circulation systems are affecting wind-fields and precipitation zones and these, in turn, are changing migration patterns. We examined the consequences in a serious rice pest, the brown planthopper (BPH, Nilaparvata lugens) in East China. BPH cannot overwinter in temperate East Asia, and infestations there are initiated by several waves of windborne spring or summer migrants originating from tropical areas in Indochina. The East Asian summer monsoon, characterized by abundant rainfall and southerly winds, is of critical importance for these northward movements. We analyzed a 42-year dataset of meteorological parameters and catches of BPH from a standardized network of 341 light-traps in South and East China. We show that south of the Yangtze River during summer, southwesterly winds have weakened and rainfall increased, while the summer precipitation has decreased further north on the Jianghuai Plain. Together, these changes have resulted in shorter migratory journeys for BPH leaving South China. As a result, pest outbreaks of BPH in the key rice-growing area of the Lower Yangtze River Valley (LYRV) have declined since 2001. We show that these changes to the East Asian summer monsoon weather parameters are driven by shifts in the position and intensity of the Western Pacific subtropical high (WPSH) system that have occurred during the last 20 years. As a result, the relationship between WPSH intensity and BPH immigration that was previously used to predict the size of the immigration to the LYRV has now broken down. Our results demonstrate that migration patterns of a serious rice pest have shifted in response to the climate-induced changes in precipitation and wind pattern, with significant consequences for the population management of migratory pests.