《The American Naturalist》上刊登的“土壤水平衡与生态系统对气候变化的响应研究”

作者：Porporato A, Daly E, Rodriguez‐Iturbe I

刊物：《The American Naturalist》,2004年, 第16卷,第5期, 625-632页

关键词：土壤含水量；土壤水平衡；植物水分胁迫；随机过程；生态系统响应；气候变化

摘要：本文利用土壤水动力学随机模型针对不同生态系统的土壤水平衡进行模拟，提出了若干陆地水文循环和生态系统响应基本特征，这些特征与通过经验观测值得到的结果不尽相同。本文简化后的框架分析介绍了水文气候变异性（尤其是降雨事件发生的频率和量级）与土壤和植被分布的一致性并对对植被条件的影响机理。模型得到的结果解释并拓展了经典Budyko曲线，该曲线将蒸散发损失与干旱指数联系起来，描述了降水在蒸散发、径流和深层渗漏中的分布情况。基于两个整合了气候、土壤和植被条件的无量纲控制群组（governing dimensionless groups），文章提出了针对全球生态系统土壤水平衡的一般分类。另外，结合土壤水动力学、植物水分胁迫和碳同化之间联系，解释了近期在降雨模式发生变化的情况下野外试验观察得到的生态系统的响应结果。结论表明植被的碳同化不仅取决于其生长期内的降雨总量，而且还与降雨事件的频率和量级有关。

Soil water balance and ecosystem response to climate change

Authors： Porporato A, Daly E, Rodriguez‐Iturbe I

Journal：The American Naturalist, 2004, 164(5): 625-632.

Key Words：soil moisture; soil water balance; plant water stress; stochastic processes; ecosystem response; climate change

Abstract：Some essential features of the terrestrial hydrologic cycle and ecosystem response are singled out by confronting empirical observations of the soil water balance of different ecosystems with the results of a stochastic model of soil moisture dynamics. The simplified framework analytically describes how hydroclimatic variability (especially the frequency and amount of rainfall events) concurs with soil and plant characteristics in producing the soil moisture dynamics that in turn impact vegetation conditions. The results of the model extend and help interpret the classical curve of Budyko, which relates evapotranspiration losses to a dryness index, describing the partitioning of precipitation into evapotranspiration, runoff, and deep infiltration. They also provide a general classification of soil water balance of the world ecosystems based on two governing dimensionless groups summarizing the climate, soil, and vegetation conditions. The subsequent analysis of the links among soil moisture dynamics, plant water stress, and carbon assimilation offers an interpretation of recent manipulative field experiments on ecosystem response to shifts in the rainfall regime, showing that plant carbon assimilation crucially depends not only on the total rainfall during the growing season but also on the intermittency and magnitude of the rainfall events.

原文链接：http://www.jstor.org/discover/10.1086/424970?uid=3737800&uid=2&uid=4&sid=21102777008003

翻译：陈翔；审阅：高学睿