Detecting the response of plant functional traits to nutrient status in grassland by spectral reflectance measurements

目前草地研究的挑战是更好地了解环境条件和管理对草地特性和生产力的影响，同时考虑生产对生态系统的影响。因此，需要了解管理的草原群落如何应对人类和动物的操纵，以及如何非破坏性地检测这种反应。在混合草地，植物的操作的反应可以解释一种新的方法，是基于功能性状的表达，往往不考虑植物区系组成。众所周知，性状影响冠层上方测量的光谱特性。该项目的目的是了解如何解释光谱反射特征，以确定沿着土壤养分含量梯度的草地群落的功能特征。在两年的时间里，Rengen草原实验（自1941年以来）的冠层光学特性将被测量与起重机安装高分辨率光谱仪。复杂的光谱分析将被应用于获得光谱响应和植物性状受土壤养分状况的影响之间的函数关系。在第二年和第三年，推导出的数学模型，描述群落功能性状和光谱反射率之间的关系将验证草地领域在德国的其他地方。

The challenge of present grassland research is to better understand the impact of environmental conditions and management on sward properties and productivity and, at the same time, to consider the impact of production on the ecosystem. Hence, knowledge is required to understand how managed grassland communities respond to manipulation by humans and animals and how this response can be detected non-destructively. In mixed grassland swards, the response of plants to manipulation can be interpreted by a new approach that is based on the expression of functional traits, often irrespective of floristic composition. It is known that traits affect spectral properties as measured above the canopy. The objective of the project is to learn how spectral reflectance signatures must be interpreted to identify functional traits of grassland communities along a gradient of soil nutrient content. Throughout two years, optical properties of canopy in the Rengen Grassland Experiment (since 1941) will be measured with a crane mounted high resolution spectrometer. Sophisticated spectral analyses will be applied to derive functional relations between spectral response and plant traits as affected by soil nutrient status. In the second and third year, the derived mathematical model describing the relationship between community functional traits and spectral reflectance will be validated on grassland fields elsewhere in Germany.