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Atmospheric CO2-concentration, temperature and rainfall variability are all expected to increase in the near future. The resulting increased dynamics of soil moisture contents, together with increased plant physiological demands for both oxygen and water, will lead to an increased occurrence of wet and dry extremes of plant stresses, i.e., of oxygen and drought stress, respectively, alone and in interaction. The use of indirect environmental variables in previous studies and a focus on individual stresses rather than their combined effects has hampered understanding of the causal impact of climate change on plant species composition through changes in abiotic site conditions. Here, we use process-based simulations of oxygen and drought stresses in conjunction with a downscaled national version of IPCC scenarios in order to show that these stresses will increase (on average by ∼20% at sites where both stresses occur) in a warmer and more variable future (2050) climate. These two types of stresses will increasingly coincide, i.e. both stresses will occur more often (but not at the same time) within a single vegetation plot. We further show that this increased coincidence of water-related stresses will negatively affect the future occurrence of currently endangered plant species (causing a reduction of ∼16%), while apparently no such decrease will occur among common species. Individual stresses did not appear to affect the occurrence of endangered plant species. Consequently, our study demonstrates that species that are already threatened under the current climate will suffer most from the effects of climate change. Copyright 2011 by the American Geophysical Union.

The international research community is beginning to realise that climate extremes may be more powerful drivers of vegetation change and species extinctions than slow-and-steady climatic changes, but the causal mechanisms of such changes are presently unknown. In order to quantify oxygen and drought stress with causal measures, we focused on interacting meteorological, soil physical, microbial, and plant physiological processes in the soil-plant-atmosphere system. Contribution to the EGU General Assembly 2011.

The international research community is beginning to realise that climate extremes may be more powerful drivers of vegetation change and species extinctions than slow-and-steady climatic changes, but the causal mechanisms of such changes are presently unknown. In order to quantify oxygen and drought stress with causal measures, we focused on interacting meteorological, soil physical, microbial, and plant physiological processes in the soil-plant-atmosphere system. Contribution to the EGU General Assembly 2011.

In this study the possibilities of integrating ERS scatterometer-derived soil moisture into CGMS are explored. This remote sensed soil moisture is used to calculate drought stress in grains of barley for a Russian-Ukrainian study area. The results arecompared with drought stress based on the rainfall-driven water balance and with regional yields statistics of barley. The use of ERS scatterometer in CGMS seems promising, especially when additional input data such as sowing dates and crop parameters are improved and conversions of ERS scatterometer data into soil moisture are more specified for different soils and seasonal variations.

In this study the possibilities of integrating ERS scatterometer-derived soil moisture into CGMS are explored. This remote sensed soil moisture is used to calculate drought stress in grains of barley for a Russian-Ukrainian study area. The results arecompared with drought stress based on the rainfall-driven water balance and with regional yields statistics of barley. The use of ERS scatterometer in CGMS seems promising, especially when additional input data such as sowing dates and crop parameters are improved and conversions of ERS scatterometer data into soil moisture are more specified for different soils and seasonal variations.