Energy-balance models for non-intrusive monitoring of tree water use of overaged oak coppices in response to different management strategies
The ability of oaks to resprout quickly after cutting was exploited by a traditional forest management practice, known as coppicing. This traditional practice was abandoned since the 1960s, resulting in a high density of overaged individuals, less vigorous and particularly vulnerable. In the last decades, the Aragon Forest Services have promoted different thinning treatments in the area of El Moncayo, mainly to prevent forest fires and tree decline. Within the Project CO2PPICE, we will assess how these treatments may improve the provision of different ecosystem services. One of the specific aims is to quantify the effect on water balance of four alternative treatments (abandonment, conversion to high forest, coppice with standards and forest with pasture). Although studies on evergreen oaks and Mediterranean pines have shown that reduced stand density may increase water availability and deep percolation, this remains to be tested in deciduous Mediterranean oaks, much more profligate in the use of water. We anticipate that, under certain management scenarios, the increase of individual transpiration might compensate for the reduction in stand density. To test our hypothesis, we developed a custom-made system which delivers to the cloud continuous measurements of canopy temperature, air temperature and humidity, light environment, wind speed and soil water potential. With canopy temperature and environmental variables, transpiration rates are calculated according to an energy-balance model. Here, we will present the experimental set-up of the system, implemented under the different management regimes, and will discuss the first results for the growing season 2021.
Funded by PID2019-106701RR-I00/AEI/10.13039/501100011033.