A meta‐analysis of primary productivity and rain use efficiency in terrestrial grassland ecosystems
A meta‐analysis of primary productivity and rain use efficiency in terrestrial grassland ecosystems
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DOI：
10.1002/ldr.3715
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发表时间：
2020-10
影响因子：
4.7
通讯作者：
Zhongling Yang;S. Collins;R. Bixby;Hongquan Song;Dong Wang;Rui Xiao
中科院分区：
文献类型：
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作者：
Zhongling Yang;S. Collins;R. Bixby;Hongquan Song;Dong Wang;Rui Xiao
全面了解沿着降水梯度的年净第一性生产力（ANPP）和降水利用效率（芸香）对气候变化背景下的草地保护具有重要意义。然而，在不同的空间和时间尺度上，农业净初级生产力和芸香如何响应降水的变化仍然不确定。这项研究的目的是澄清这些事情。利用21个野外试验数据，在32个样点（其中18个在中国）中，研究了草地生态系统年平均降水量（MAP）与ANPP和芸香的时空关系。研究表明，ANPP和芸香对降水时空变化的敏感性不同。首先，分析支持ANPP和MAP之间众所周知的正线性关系。其次，我们发现，无论研究地点的实际降水量如何，ANPP都随着降水量的增加而增加，而降水量每变化1 mm，ANPP增加0.2 g m−2。第三，芸香增加，增加跨站点的MAP，而芸香一般在大多数站点内的年降水量下降。最后，在芸香的时间变化的网站内是低于整个空间格局的变化跨网站。缺乏一致性的ANPP和芸香之间的年和跨站点响应降水的年际变化表明表征降水变化的生态指标的复杂性。这些发现突出了降水-ANPP关系中站点特异性变化的普遍性。
A comprehensive understanding of annual net primary productivity (ANPP) and rain‐use efficiency (RUE) along precipitation gradients is critial for grassland conservation under climate change. However, how ANPP and RUE respond to changes in precipitation at different spatial and temporal scales remains uncertain. The aim of this research was to clarify these things. Using data from 21 field experiments, with an average sampling period of 14.3 years in 32 sites, 18 of which are in China, we evaluated the relationship of mean annual precipitation (MAP) with ANPP and RUE across spatial and temporal scales in grassland ecosystems. Our study showed different degrees of sensitivity of ANPP and RUE to changing precipitation spatially and temporally. First, analysis supports the well‐known positive linear relationship between ANPP and MAP. Second, we found that ANPP increases with increasing precipitation regardless of the actual precipitation amount of the study sites, whereas ANPP increased 0.2 g m−2 more than it declined per 1 mm change in precipitation. Third, RUE increased with increasing MAP across sites, whereas RUE generally decreased with annual precipitation within most sites. Finally, the temporal variation in RUE within sites is lower than the overall spatial pattern of variation across sites. The lack of consistency in ANPP and RUE among years and across sites in response to interannual variation in precipitation indicates the complexity of ecological indicators characterizing precipitation changes. These findings highlight the prevalence of site‐specific variation in precipitation‐ANPP relationships.