Assessment of different methods for Evapotranspiration and Soil Moisture for various land use areas across Poland

The main goal of the study w as to determine the evapotranspiration and soil moisture fordifferent ecosystems as grasslands, grassland wetlands and agriculture fields in Pokand. There is asignificant potential to estimate water usage by plants and to illustrate how they return water tothe atmosphere by applying the soil vegetation temperature measured now days by satellites.The proper assessment of evapotranspiration and soil moisture content are essential in foodsecurity research, land management, climate change observations and hydrological modellingCollected ground data covers grasslands areas (intensive and extensive management), at theJECAM Joint Experiment for Crop Assessment and Monitoring. Ground data collectionincluded measurements of soil moisture, biomass samples and agrometeorological parameters.It was possible to collect the data from ECOSTRESS (temperature and latent heat flux LE )for JECAM fields for different dates during vegetation growth and few acquisitions ofECOSTRESS  for the grasslands for the whole NUTS2 where the JECAM area exists. For thegrassland of wetlands in the North of Poland there were only two ECOSTRES S acquisition s.At the same time of ECOSTRES S acquisition the data from Terra MODIS, Sentinel 2 andSentinel 3 were collected in order to calculate the vegetation indices and get the surfacetemperature. At the JECAM field we conducted the measurements of meteorologicalparameters. At the grass area of wetlands we installed the Eddy Covariance tower for fluxmeasurements and twenty soil moisture sondes with permanent measurements. The LE valuesobtained from ECOSTRESS data were compared to the latent heat (calculated as the componentof energy budget). Surface temperature derived from thermal channels of Terra MODIS andSentinel 3 in conjunction with meteorological data have been used for calculation of LE as aresidual of the of the simplified energy budget equation (Dabrowska Zielinska et al., 2022 ). Atthe same time different vegetation parameters were calculated from Sentinel’s index NDVI toestablish the correlation between the vegetation phase of development soil moisture values andevapotranspiration conditions. Climate conditions influence evapotranspiration throughavailable soil moisture. Vegetation influence evapotranspiration through its biomass, plantheight and vegetation response to soil moisture. Created models applying measured LE byECOSTRESS and vegetation parameters allowed to transfer the water demand by plants toother areas. For understanding the mechanistic responses of ecosystem processes toenvironmental change it is important to examine evapotranspiration its annual change fordifferent ecosystems with the available data for vali dation. The study used artificial intelligencemethods including machine learning techniques for modelling evapotranspirationDąbrowska - Zielińska K., Misiura K., Malińska A., Gurdak R., Grzybowski P., Bartold M., Kluczek M., 2022,Spatiotemporal estimation of gross primary production for terrestrial wetlands using satellite and field data,Remote Sens. Appl.: Soc. Environ. doi:10.1016/j.rsase.2022.100786The study has been done for the project: GrasSat "Tools for information to farmers on grasslands yields understressed conditions to support management practices" NOR/POLNOR/GrasSAT/0031/2019  financed byNarodowe Centrum Badań i Rozwoju (NCBIR)