新陈代谢是生物的基本生理过程。生态学代谢理论(metabolic theory of ecology)基于生物个体大小和环境温度对个体新陈代谢过程的影响,使用尺度推移(scaling)的方法来解释多种生态学格局和过程。James Borwn等将这一理论用于解释物种多...新陈代谢是生物的基本生理过程。生态学代谢理论(metabolic theory of ecology)基于生物个体大小和环境温度对个体新陈代谢过程的影响,使用尺度推移(scaling)的方法来解释多种生态学格局和过程。James Borwn等将这一理论用于解释物种多样性的大尺度格局,并从机制上解释了物种多样性与环境温度的关系。这一理论提出了两个明确的预测:(1)物种多样性的对数与绝对温度的倒数之间呈线性关系;(2)这一线性关系的斜率为–0.6至–0.7。这一理论自提出以来,饱受争议,经过了正反两方面经验数据的检验,目前仍未形成一致的结论。虽然这一理论仍面临着一些有待解决的问题,但它以崭新的思路和方法有别于以往的基于统计学方法的研究。人们过去对该理论的实证检验忽略了两个重要的约束条件,即除温度以外的环境条件处于理想状态和群落处于平衡状态,而这两个约束条件是理解该理论的基础。本文对生态学代谢理论的理论框架、预测和含义,以及以往的检验结果进行阐述,在此基础上提出了作者对该理论的若干认识和未来研究中应考虑的若干问题。展开更多
物种多样性地理分布格局及其成因是生物地理学和宏观生态学研究的核心问题之一。为了解释物种多样性的分布格局,人们提出了多种假说,其中讨论最多的是能量假说。该假说认为,物种多样性的变化受能量控制。根据能量的不同形式及其对物种...物种多样性地理分布格局及其成因是生物地理学和宏观生态学研究的核心问题之一。为了解释物种多样性的分布格局,人们提出了多种假说,其中讨论最多的是能量假说。该假说认为,物种多样性的变化受能量控制。根据能量的不同形式及其对物种多样性的影响机制,能量假说包括以下几种形式:生产力假说(productivity hypothesis)、水分—能量动态假说(water-energy dynamic hypothesis)、环境能量假说(ambientenergy hypothesis)、寒冷忍耐假说(freezing tolerance hypothesis)以及生态学代谢假说(metabolic theory of ecology,MTE)。本文系统介绍了每种能量假说的含义、所使用的能量形式及表征变量,以及对物种多样性的影响机制,并对不同形式的能量假说进行了比较,在此基础上,分析了每种能量假说的优点和缺点以及各自面临的问题。展开更多
解释群落的物种多样性大小是生态学研究的一个重要的理论和实践问题。人们提出了群落物种多样性的多种假说,Zobel等人提出的种库假说(species pool hypothesis)是生物多样性理论研究的重要发展。该假说认为,一个群落的物种多样性不仅与...解释群落的物种多样性大小是生态学研究的一个重要的理论和实践问题。人们提出了群落物种多样性的多种假说,Zobel等人提出的种库假说(species pool hypothesis)是生物多样性理论研究的重要发展。该假说认为,一个群落的物种多样性不仅与环境条件和生态过程(ecological process)(如竞争、捕食)有关,也受区域种库(regional species pool)的限制。区域种库是指一个地区可进入某一群落的潜在物种数量,它由地史过程(如冰期、地质年代)和区域过程(物种形成、迁移扩散以及消亡)所决定。按照种库假说,某一生境类型的面积越大,地质年代越古老,物种形成的机会也就越多,因而能适应和分布于该生境的物种也就越多,实际群落中的物种丰富度也就越高。种库在空间上主要有两个层次:区域种库和实际种库,前者指某一生境所拥有的潜在物种数量,主要由生物地理过程(biogeographic processes)所决定;后者则为调查的群落中实际出现的物种数量,主要由竞争等生态过程和区域种库共同决定。本文对种库假说的基本概念、主要内容、种库确定方法等作了介绍,并阐述了作者对这些问题的理解和认识。展开更多
Eight temperate deciduous tree species, Acer rubrum L., A. saccharinum L., A. saccharum Marsh., Belluta alleghaniensis Britton., Fraxinus nigra Marsh., Quercus rubra L., Titia americana L., and Ulmus americana L. in e...Eight temperate deciduous tree species, Acer rubrum L., A. saccharinum L., A. saccharum Marsh., Belluta alleghaniensis Britton., Fraxinus nigra Marsh., Quercus rubra L., Titia americana L., and Ulmus americana L. in eastern North America, were selected to explore relationship between the northward distribution of temperate tree species and climatic factors. For each species, more than 30 sites at their north limits of distribution were obtained from their distribution maps, and 11 climatic indices at the north limits were computed. The standardized standard deviation (SD) method, which compares the magnitude of variance of climatic indices, was used to detect which climatic parameter was the most important for explaining northward distribution of these species. We presume that the climatic parameter that has the smallest variance at the north limit would be assigned as the dominant climatic factor for limiting the distribution of this species. The results derived from the standardized SD method indicated that the SD value of warmth index (WI) and/or annual biotemperature (ABT) were the smallest among the 11 climatic indices. Since both WI and ABT represent growing season temperature, it suggested that growing season temperature was the most important climatic factor for explaining the northward distribution of these temperate tree species. The relationships between several climatic indices, WI, coldness index (CI), annual precipitation (AP), annual range of temperature (ART) and humid/arid index were also analyzed. As a result, at the north limits of all these species, both WI and CI decreased with an increase of AP, and CI increased with an increase of ART. Besides growing season temperature, precipitation and climatic continentality also have influence on the northward distribution of the temperate trees in eastern North America.展开更多
文摘新陈代谢是生物的基本生理过程。生态学代谢理论(metabolic theory of ecology)基于生物个体大小和环境温度对个体新陈代谢过程的影响,使用尺度推移(scaling)的方法来解释多种生态学格局和过程。James Borwn等将这一理论用于解释物种多样性的大尺度格局,并从机制上解释了物种多样性与环境温度的关系。这一理论提出了两个明确的预测:(1)物种多样性的对数与绝对温度的倒数之间呈线性关系;(2)这一线性关系的斜率为–0.6至–0.7。这一理论自提出以来,饱受争议,经过了正反两方面经验数据的检验,目前仍未形成一致的结论。虽然这一理论仍面临着一些有待解决的问题,但它以崭新的思路和方法有别于以往的基于统计学方法的研究。人们过去对该理论的实证检验忽略了两个重要的约束条件,即除温度以外的环境条件处于理想状态和群落处于平衡状态,而这两个约束条件是理解该理论的基础。本文对生态学代谢理论的理论框架、预测和含义,以及以往的检验结果进行阐述,在此基础上提出了作者对该理论的若干认识和未来研究中应考虑的若干问题。
文摘物种多样性地理分布格局及其成因是生物地理学和宏观生态学研究的核心问题之一。为了解释物种多样性的分布格局,人们提出了多种假说,其中讨论最多的是能量假说。该假说认为,物种多样性的变化受能量控制。根据能量的不同形式及其对物种多样性的影响机制,能量假说包括以下几种形式:生产力假说(productivity hypothesis)、水分—能量动态假说(water-energy dynamic hypothesis)、环境能量假说(ambientenergy hypothesis)、寒冷忍耐假说(freezing tolerance hypothesis)以及生态学代谢假说(metabolic theory of ecology,MTE)。本文系统介绍了每种能量假说的含义、所使用的能量形式及表征变量,以及对物种多样性的影响机制,并对不同形式的能量假说进行了比较,在此基础上,分析了每种能量假说的优点和缺点以及各自面临的问题。
文摘解释群落的物种多样性大小是生态学研究的一个重要的理论和实践问题。人们提出了群落物种多样性的多种假说,Zobel等人提出的种库假说(species pool hypothesis)是生物多样性理论研究的重要发展。该假说认为,一个群落的物种多样性不仅与环境条件和生态过程(ecological process)(如竞争、捕食)有关,也受区域种库(regional species pool)的限制。区域种库是指一个地区可进入某一群落的潜在物种数量,它由地史过程(如冰期、地质年代)和区域过程(物种形成、迁移扩散以及消亡)所决定。按照种库假说,某一生境类型的面积越大,地质年代越古老,物种形成的机会也就越多,因而能适应和分布于该生境的物种也就越多,实际群落中的物种丰富度也就越高。种库在空间上主要有两个层次:区域种库和实际种库,前者指某一生境所拥有的潜在物种数量,主要由生物地理过程(biogeographic processes)所决定;后者则为调查的群落中实际出现的物种数量,主要由竞争等生态过程和区域种库共同决定。本文对种库假说的基本概念、主要内容、种库确定方法等作了介绍,并阐述了作者对这些问题的理解和认识。
文摘Eight temperate deciduous tree species, Acer rubrum L., A. saccharinum L., A. saccharum Marsh., Belluta alleghaniensis Britton., Fraxinus nigra Marsh., Quercus rubra L., Titia americana L., and Ulmus americana L. in eastern North America, were selected to explore relationship between the northward distribution of temperate tree species and climatic factors. For each species, more than 30 sites at their north limits of distribution were obtained from their distribution maps, and 11 climatic indices at the north limits were computed. The standardized standard deviation (SD) method, which compares the magnitude of variance of climatic indices, was used to detect which climatic parameter was the most important for explaining northward distribution of these species. We presume that the climatic parameter that has the smallest variance at the north limit would be assigned as the dominant climatic factor for limiting the distribution of this species. The results derived from the standardized SD method indicated that the SD value of warmth index (WI) and/or annual biotemperature (ABT) were the smallest among the 11 climatic indices. Since both WI and ABT represent growing season temperature, it suggested that growing season temperature was the most important climatic factor for explaining the northward distribution of these temperate tree species. The relationships between several climatic indices, WI, coldness index (CI), annual precipitation (AP), annual range of temperature (ART) and humid/arid index were also analyzed. As a result, at the north limits of all these species, both WI and CI decreased with an increase of AP, and CI increased with an increase of ART. Besides growing season temperature, precipitation and climatic continentality also have influence on the northward distribution of the temperate trees in eastern North America.
