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Grassland plays an important role in German agriculture. The interplay of ecological processes in grasslands secures important ecosystem functions and, thus, ultimately contributes to essential ecosystem services. To sustain, e.g., the provision of fodder or the filter function of soils, agricultural management needs to adapt to site-specific grassland characteristics. Spatially explicit information derived from remote sensing data has been proven instrumental for achieving this. In this study, we analyze the potential of Sentinel-2 data for deriving grassland-relevant parameters. We compare two well-established methods to calculate the aboveground biomass and leaf area index (LAI), first using a random forest regression and second using the soil–leaf-canopy (SLC) radiative transfer model. Field data were recorded on a grassland area in Brandenburg in August 2019, and were used to train the empirical model and to validate both models. Results confirm that both methods are suitable for mapping the spatial distribution of LAI and for quantifying aboveground biomass. Uncertainties generally increased with higher biomass and LAI values in the empirical model and varied on average by a relative RMSE of 11% for modeling of dry biomass and a relative RMSE of 23% for LAI. Similar estimates were achieved using SLC with a relative RMSE of 30% for LAI retrieval, and a relative RMSE of 47% for the estimation of dry biomass. Resulting maps from both approaches showed comprehensible spatial patterns of LAI and dry biomass distributions. Despite variations in the value ranges of both maps, the average estimates and spatial patterns of LAI and dry biomass were very similar. Based on the results of the two compared modeling approaches and the comparison to the validation data, we conclude that the relationship between Sentinel-2 spectra and grassland-relevant variables can be quantified to map their spatial distributions from space. Future research needs to investigate how similar approaches perform across different grassland types, seasons and grassland management regimes.

The aim of the investigation was to determine the water requirements of adult fallow deer (Dama dama), Skudde sheep (Ovis ammon) and mouflon (Ovis orientalis musimon) kept under the same conditions. This study was intended to allow the development of basic principles and recommendations for improving drinking water management in the production of fallow deer, sheep, and mouflon, taking into account the different reproductive statuses of these three species. At a fen, the water intake of the animals was recorded for three consecutive years (2011–2013) during the grazing period (1 May–31 October). The results were based on the regular measurement of the animals’ water intake under pasture management. Three herd repetitions were carried out per species during early and late summer and autumn. Each test group consisted of 10 adult female animals. To enable a comparison of the drinking water consumption among species of different weights, the water intake of each animal was converted into the water intake per kg of metabolic live weight (W0.75). During the early summer fallow deer and sheep consumed a similar amount of water. The mouflon had relatively low water consumption; in the late summer and autumn (September and October), these animals drank only sporadically. All three species consumed more water in the first 3 months of the grazing period than in the last 3 months. Daily water consumption by sheep and deer increased with heat stress caused by higher temperatures and relative humidity, whereas mouflon were relatively immune to such environmental influences. It is recommended that the small ruminant species investigated should be offered a constant supply of drinking water when under pasture management.

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