## 5 Discussion
### Effects for Different Land Cover Types  
Within this study, we can depict variations in the characteristics of agricultural droughs for different land cover types. Croplands are managed, and management strategies are often adapted toward varying weather conditions. During drought conditions in summer, premature ripening potentially occurs in cereal, which has to be harvested earlier than normal. This was also the case for cereal crops in 2018, where major harvesting was already finished in mid of August [48]. In 2018, the situation in cropland relaxed in October and November. The more or less average EVI signal was possibly provoked by earlier than usual intermediate crop cultivations. The signal of intermediate crops is determined by a growing onset and greening of the intermediate crop vegetation and, therefore, leads to a normal EVI signal on average. In grassland, the vegetation stayed stressed until the very endof the vegetation period. The negative EVI anomaly for grassland in Germany reached its maximum in August 2018 and stayed high. There was no recovery visible in parts until next year's spring (not shown). From an agricultural point of view, there was only one cut possible in agriculturally used grasslands in 2018, and no further harvesting was possible for the rest of the year [48]. Considering forests, no negative deviations could be observed in the drought year 2018 (Figure S1). We assume that the reaction of trees to drought has a larger lag or is not present at all, as trees are able to reach soil water from further below compared to crop or grass species [27; 49]. In a study on the effects of the 2003 drought event on a central European deciduous forest [50], the trees did not show water stress, which would be in accordance with our findings. However, even though the EVI deviances are not strong, the year 2003 and the three following years (2004, 2005, and 2006) all show negative effects in our results. This might be a lagged effect of the 2003 drought. In another study, forests show a strongly delayed response to climate extreme conditions [27]. In 2018, especially April and May show positive effects in forested areas. In energy-limited regions higher temperatures and long sunshine durations can lead to higher photosynthetic activity of the vegetation. This might be especially true for forests, as trees reach deeper soil layers and have better access to soil water. A positive anomaly of photosynthetic activity during drought and heat conditions was also found in other studies for (central European) forests [27; 49]. More research focused on drought effects on forests is needed to understand when negative (possibly long-term) impacts occur and when drought conditions trigger positive effects in forests. There are several impacts of drought and heat events, such as a stress-related decrease in vegetation functioning or a complete destruction of the vegetation [9]. Water and chemical cycles and productivity of ecosystems are affected. Vegetation cover--in particular grasslands--react with increased evaporation to hot conditions, leading to an additional reduction of soil moisture and enhanced drought conditions [51]. This effect is assumed to have contributed to the extreme drought and heat in Europe in 2003 [51] and might also have played a role in 2018. It is expected to be a major influencing factor in future drought and heat events [52]. The effect on the carbon cycle is also of great importance as temperate ecosystems were assumed to increase carbon sequestration due to higher temperatures in future climates [53]. However, many ecosystem types possibly turn from carbon sink to carbon source, also in a long-term perspective [54; 55], as the number of extreme events as heats and droughs will rise in the future [5]. The negative impact on productivity is especially problematic for the agricultural sector as yields and fodder are lost, which are often related to high additional costs.