Boot René G A, den Dubbelden Koen C
Department of Plant Ecology and Evolutionary Biology, University of Utrecht, Lange Nieuwstraat 106, 3512 PN, Utrecht, The Netherlands.
Oecologia. 1990 Nov;85(1):115-121. doi: 10.1007/BF00317351.
We studied the effects of nitrogen supply on growth, allocation, and gas exchange characteristics of two perennial grasses of dry, nutrient-poor inland dunes: Corynephorus canescens (L.) Beauv. and Agrostis vinealis Schreber. C. canescens invests more biomass in leaves and less in roots, but has less leaf area and more root length per unit plant weight than A. vinealis. A. vinealis invests more nitrogen per unit leaf weight, but less per unit leaf area, despite a similar relative nitrogen investment in leaves and plant nitrogen concentration. Between-species differences in the rate of net photosynthesis, transpiration and shoot respiration are positively related to leaf nitrogen content per unit leaf area. The rate of net photosynthesis per unit plant weight is higher for A. vinealis at both levels of nitrogen supply, due to differences in leaf area ratio (LAR), and despite the reverse differences in the rate of net photosynthesis per unit leaf area. The water use efficiency of the two species is similar and increases significantly with an increase in nitrogen supply. The photosynthetic nitrogen use efficiency on the other hand is not affected by nitrogen supply, while at both low and high nitrogen supply A. vinealis has a 10% higher photosynthetic nitrogen use efficiency than C. canescens.
我们研究了氮素供应对两种生长于干旱、养分贫瘠内陆沙丘的多年生草本植物的生长、分配及气体交换特征的影响，这两种植物分别是灰绿臂形草（Corynephorus canescens (L.) Beauv.）和葡枝剪股颖（Agrostis vinealis Schreber）。与葡枝剪股颖相比，灰绿臂形草在叶片中投入更多生物量，在根系中投入较少，但单位植株重量的叶面积较小，根长度较长。葡枝剪股颖单位叶重投入的氮素更多，但单位叶面积投入的氮素较少，尽管其叶片中相对氮素投入和植株氮浓度与灰绿臂形草相似。种间净光合速率、蒸腾速率和地上部呼吸速率的差异与单位叶面积的叶氮含量呈正相关。由于叶面积比（LAR）的差异，在两种氮素供应水平下，葡枝剪股颖单位植株重量的净光合速率均较高，尽管单位叶面积的净光合速率存在相反的差异。两种植物的水分利用效率相似，且随氮素供应增加而显著提高。另一方面，光合氮利用效率不受氮素供应影响，在低氮和高氮供应条件下，葡枝剪股颖的光合氮利用效率均比灰绿臂形草高10%。
