Hu Ya, Zuo Xiaoan, Yue Ping, Zhao Shenglong, Guo Xinxin, Li Xiangyun, Medina-Roldán Eduardo
Urat Desert-Grassland Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China.
Naiman Desertification Research Station, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou 730000, China.
Plants (Basel). 2020 Oct 29;9(11):1463. doi: 10.3390/plants9111463.
Understanding the effects of precipitation variations on plant biochemical and functional traits is crucial to predict plant adaptation to future climate changes. The dominant species, , plays an important role in maintaining the structure and function of plant communities in the desert steppe, Inner Mongolia. However, little is known about how altered precipitation affects biochemical and functional traits of in different communities in the desert steppe. Here, we examined the responses of biochemical and functional traits of in shrub- and grass-dominated communities to experimentally increased precipitation (control, +20%, +40%, and +60%). We found that +40% and +60% increased plant height and leaf dry matter content (LDMC) and decreased specific leaf area (SLA) of in grass community. For biochemical traits in grass community, +60% decreased the contents of protein and chlorophyll b (Cb), while +40% increased the relative electrical conductivity and superoxide dismutase. Additionally, +20% increased LDMC and malondialaenyde, and decreased SLA and protein in shrub community. Chlorophyll a, Cb, carotenoids, protein and superoxide dismutase in the grass community differed with shrub community, while +60% caused differences in SLA, LDMC, leaf carbon content, malondialaenyde and peroxidase between two communities. The positive or negative linear patterns were observed between different functional and biochemical traits in grass- rather than shrub-community. Soil water content explained changes in some biochemical traits in the grass community, but not for functional traits. These results suggest that increased precipitation can affect functional traits of in the grass community by altering biochemical traits caused by soil water content. The biochemical and functional traits of were more sensitive to extreme precipitation in grass- than shrub-community in the desert steppe. Our study highlights the important differences in adaptive strategies of in different plant communities at the same site to precipitation changes.
了解降水变化对植物生化和功能性状的影响对于预测植物对未来气候变化的适应性至关重要。优势物种 在内蒙古荒漠草原植物群落的结构和功能维持中发挥着重要作用。然而，关于降水变化如何影响荒漠草原不同群落中 的生化和功能性状，我们知之甚少。在此，我们通过实验性增加降水量（对照、+20%、+40%和+60%），研究了灌木和草本主导群落中 的生化和功能性状的响应。我们发现，在草本群落中，降水量增加40%和60%时， 的株高和叶片干物质含量（LDMC）增加，比叶面积（SLA）降低。对于草本群落中的生化性状，降水量增加60%时，蛋白质和叶绿素b（Cb）含量降低，而降水量增加40%时，相对电导率和超氧化物歧化酶增加。此外，在灌木群落中，降水量增加20%时，LDMC和丙二醛增加，SLA和蛋白质降低。草本群落中的叶绿素a、Cb、类胡萝卜素、蛋白质和超氧化物歧化酶与灌木群落不同，而降水量增加60%时，两个群落之间的SLA、LDMC、叶片碳含量、丙二醛和过氧化物酶存在差异。在草本群落而非灌木群落中，不同功能和生化性状之间呈现出正或负的线性关系。土壤含水量解释了草本群落中一些生化性状的变化，但不能解释功能性状的变化。这些结果表明，降水量增加可通过改变土壤含水量引起的生化性状来影响草本群落中 的功能性状。在荒漠草原中， 的生化和功能性状在草本群落中比在灌木群落中对极端降水更为敏感。我们的研究突出了同一地点不同植物群落中 对降水变化的适应策略的重要差异。
