• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Linking plant community composition and ecosystem dynamics: Interactions of plant traits determine the ecosystem effects of plant species and plant species mixtures.
【24h】

Linking plant community composition and ecosystem dynamics: Interactions of plant traits determine the ecosystem effects of plant species and plant species mixtures.

机译：将植物群落组成与生态系统动态联系起来：植物性状的相互作用决定了植物物种和植物物种混合物对生态系统的影响。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

I examined the mechanisms by which plant species and plant species mixtures influence N dynamics, soil phosphorus and decomposition in a California annual grassland. I established plots of eight grassland species in monoculture, and in two-, three- and five-species mixtures. Plant species influenced ecosystem processes through an interaction of different mechanisms, including litter quality and quantity, aboveground live biomass, labile carbon (C) inputs (exudation and tissue turnover), and influences on soil microclimate (Chapter 1). Species affected ecosystem processes through unique combinations of these mechanisms, and the relative importance of these mechanisms changed over time. Litter quality was the dominant mechanism by which plant species influenced early stages of decomposition, but labile C inputs became more important in the later stages of decomposition. Plant species effects on nitrogen (N) cycling were in part dependent on both litter quality and labile C inputs, but plant effects on soil temperature and moisture played a critical role at the time of the growing season when these factors most limited plant growth and microbial activity. Plant composition had only small effects on soil phosphate and microbial phosphorus (P), which were more strongly influenced by other factors such as slope position.; In order to understand the roles plant species play in ecosystems, it is vital to consider how they influence the activity and distribution of other organisms that play large roles in ecosystems. Plant species influenced the timing, type and extent of gopher activity, and in turn, this plant-gopher interaction greatly altered patterns of nitrogen cycling (Chapter 2). Plant species were also associated with distinct functional profiles of the bacterial community (Chapter 3); these profiles were closely related to plant labile C inputs. While these interactions between the plant community and bacterial substrate utilization profiles correlated with ecosystem processes, variations in bacterial community function, independent of plant composition, also correlated with ecosystem processes.; Bacterial C utilization profiles in plant mixtures were not an additive function of the component monocultures, and this may, in part, account for the non-additive effects of plant mixtures on ecosystems. The non-additive effects of plant mixtures were also related to combinations of plant substrates impacting the activity of the microbial community. For example, legumes enhanced decomposition of recalcitrant litter. Another mechanism that accounted for non-additive effects of plant mixtures on ecosystem processes was changes in plant traits when grown in mixture. Shifts in litter quality, labile C inputs, aboveground biomass, and effects on soil temperature all were associated with non-additive effects of plant mixtures on N cycling.; Overall, plant traits can be used to understand many effects of plant communities on ecosystems by providing mechanistic links between ecosystem processes and the interactions between plant traits, plant species, and plants with other organisms.
机译：我研究了植物物种和植物物种混合物影响加利福尼亚州一年生草原的氮素动态，土壤磷和分解的机制。我在单一养殖中以两种，三种和五种混合物建立了八个草地物种的地块。植物物种通过不同机制的相互作用影响生态系统过程，这些机制包括凋落物质量和数量，地上活生物量，不稳定的碳（C）输入（渗出和组织周转）以及对土壤小气候的影响（第1章）。物种通过这些机制的独特组合影响了生态系统过程，并且这些机制的相对重要性随时间而改变。凋落物质量是植物物种影响分解早期阶段的主要机制，但是不稳定的碳输入在分解后期阶段变得更为重要。植物物种对氮（N）循环的影响部分取决于凋落物质量和不稳定的碳输入，但是在生长季节时，植物因子对土壤温度和水分的影响起着关键作用，而这些因素最限制了植物的生长和微生物活动。植物组成对土壤磷酸盐和微生物磷（P）的影响很小，而这些因素受坡度等其他因素的影响更大。为了了解植物物种在生态系统中的作用，至关重要的是考虑它们如何影响在生态系统中发挥重要作用的其他生物的活动和分布。植物物种影响了地鼠活动的时间，类型和程度，进而，这种植物与植物之间的相互作用极大地改变了氮循环的模式（第二章）。植物种类也与细菌群落的不同功能特征有关（第3章）；这些概况与植物不稳定的C输入密切相关。虽然植物群落和细菌底物利用状况之间的这些相互作用与生态系统过程相关，但细菌群落功能的变化（与植物组成无关）也与生态系统过程相关。植物混合物中细菌C的利用情况不是单一栽培成分的累加函数，这可能部分解释了植物混合物对生态系统的非累加作用。植物混合物的非累加作用还与影响微生物群落活性的植物底物组合有关。例如，豆类增强了顽固垃圾的分解。解释植物混合物对生态系统过程的非累加作用的另一种机制是在混合物中生长时植物性状的变化。凋落物质量，不稳定的碳输入，地上生物量的变化以及对土壤温度的影响都与植物混合物对氮循环的非累加作用有关。总体而言，通过提供生态系统过程之间的机械联系以及植物性状，植物物种和植物与其他生物之间的相互作用，植物性状可用于了解植物群落对生态系统的许多影响。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号