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性质和生产力的影响，同时考虑生产对生态系统的影响。因此，需要了解受管理的草原社区如何应对人类和动物的操纵，以及如何以非破坏性的方式检测这种反应。在混合草原沼泽中，植物对操纵的反应可以通过一种新的方法来解释，这种方法基于功能特征的表达，通常与植物区系组成无关。众所周知，特征会影响冠层以上测量的光谱特性。该项目的目标是了解必须如何解释光谱反射特征，以确定沿土壤养分含量梯度的草原群落的功能特征。在两年的时间里，将使用安装在起重机上的高分辨率光谱仪测量仁根草原实验(自1941年以来)树冠的光学性质。复杂的光谱分析将被用来推导光谱响应和受土壤养分状况影响的植物特征之间的函数关系。在第二年和第三年，描述群落功能特征与光谱反射率之间关系的数学模型将在德国其他地方的草地上得到验证。

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.