Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun, China.
Plant Biol (Stuttg). 2020 Nov;22(6):1123-1132. doi: 10.1111/plb.13153. Epub 2020 Aug 9.
Nutrient resorption, one of the most important strategies for plant nutrient conservation, is significantly affected by soil fertility. However, the effects of experimentally altered soil fertility on plant N and P resorption are poorly understood. The potential nutrient resorption response mechanisms of the dominant species Leymus chinensis to six N addition levels (0, 2.5, 5, 10, 20 and 40 g·N·m ·year ), two P addition levels (0 and 10 g P·m ·year ) and their interactions were studied after 3 years of treatments in a temperate meadow steppe. In both green leaves and culms, N and P addition significantly increased N and P concentrations, respectively. Nitrogen addition led to a decrease in the N resorption efficiency (NRE) of both leaves and culms. Within each N treatment, P addition decreased the P resorption efficiency (PRE) of both leaves and culms and the NRE of leaves, except in the N2.5 treatment. Both NRE and PRE in leaves were higher than those in culms under N and P addition conditions. The nutrient concentrations and resorption efficiency were significantly correlated with the soil nutrient availability. Our results suggest that plants rely more on nutrient absorption from the soil, reducing the proportion of elements obtained through nutrient resorption in nutrient-rich environments.
养分回收是植物养分保护的最重要策略之一，受土壤肥力的显著影响。然而，实验改变土壤肥力对植物氮和磷回收的影响还知之甚少。本研究通过 3 年的处理，研究了温带草地草原上 6 个氮添加水平（0、2.5、5、10、20 和 40 g·N·m·year）、2 个磷添加水平（0 和 10 g·P·m·year）及其相互作用对优势种羊草的潜在养分回收响应机制。在绿叶和茎中，氮和磷的添加都显著增加了氮和磷的浓度。氮添加导致叶片和茎中氮回收效率（NRE）分别降低。在每个氮处理中，磷添加降低了叶片和茎中磷回收效率（PRE）以及叶片中的 NRE，除了在氮处理 2.5 中。在氮和磷添加条件下，叶片中的养分浓度和回收效率均高于茎中的养分浓度和回收效率。养分浓度和回收效率与土壤养分供应显著相关。我们的研究结果表明，在养分丰富的环境中，植物更多地依赖于从土壤中吸收养分，从而减少通过养分回收获得的元素的比例。
