@misc{MajauraBoehmFreese, author = {Majaura, Marie and B{\"o}hm, Christian and Freese, Dirk}, title = {Effects of agroforestry systems on microclimate and water availability as determinants for sustainable soil productivity}, series = {4th World Congress on Agroforestry : 20-22 May 2019, Le Corum, Montpellier, France, Book of Abstracts}, journal = {4th World Congress on Agroforestry : 20-22 May 2019, Le Corum, Montpellier, France, Book of Abstracts}, pages = {669}, abstract = {Recent studies have shown that hedgerows in short rotation alley cropping systems (SRACS) can improve the microclimate in adjacent crop alleys through, e.g., a reduction of daytime temperature, wind speed and evaporation (Kanzler et al. 2018). Improved microclimatic conditions may positively affect crop yields by increasing the availability of water for the crop. However, studies that examine the interdependencies between microclimate changes caused by hedgerows in SRACS, water availability and crop yields are rare. In a poplar SRACS, we investigate with high spatial and temporal resolution if changes in microclimate affect water availability for two crops and crop yields. For this purpose, we use stationary weather stations installed in a transect and mobile sensors in four strips running parallel to the stationary transect at different distances from tree strips (Fig. 1) and in a monoculture. At all measuring points air temperature, air humidity and Pich{\´e} evaporation will be continuously determined. In addition, wind speed, global radiation and precipitation will be measured at the stationary weather stations. Furthermore, transpiration of crops will be determined at different times close to all microclimate points. Subsequent crop yield sampling will then enable us to determine the degree to which tree strips in ACS influence microclimate and water availability for crops at different distances from tree strips and how these relate to small-scale changes in crop yield.}, language = {en} } @misc{MajauraBoehmFreese, author = {Majaura, Marie and B{\"o}hm, Christian and Freese, Dirk}, title = {The influence of trees on crop yields in temperate zone alley cropping systems : a review}, series = {Sustainability}, volume = {16}, journal = {Sustainability}, number = {8}, issn = {2071-1050}, doi = {10.3390/su16083301}, abstract = {Agroforestry is a multifunctional land use system that represents a promising approach to mitigate the environmental impact of agriculture while enhancing the resilience of agricultural systems and ensuring sustainable food production. However, the tree rows in agroforestry systems, particularly in alley cropping systems (ACS), can affect crop productivity on adjacent agricultural fields through various mechanisms. Hence, concerns about declining yields and reduced farm profitability persist and explain the reluctance of farmers to implement ACS on their land. In this review, we examine the available literature on the effects of temperate ACS on yields of various agricultural crops to evaluate if and to what extent crop yields in ACS are affected by tree presence. We identified that ACS crop yields often vary substantially across different species, geographical locations, weather conditions and ACS designs. Our analysis also revealed that several parameters are modified in ACS by the presence of tree rows affecting crop yields positively or negatively and that ACS design aspects play a crucial role in determining crop productivity.}, language = {en} } @misc{MajauraSutterluettiBoehmetal., author = {Majaura, Marie and Sutterl{\"u}tti, Rahel and B{\"o}hm, Christian and Freese, Dirk}, title = {High and dry : barley (Hordeum vulgare) yield benefits from tree presence in a temperate alley cropping system during a drought year}, series = {Agroforestry systems}, volume = {99}, journal = {Agroforestry systems}, number = {6}, publisher = {Springer Science and Business Media LLC}, address = {Dordrecht}, issn = {0167-4366}, doi = {10.1007/s10457-025-01267-9}, pages = {1 -- 20}, abstract = {Alley cropping systems (ACS) are promoted as sustainable, resilient and multifunctional land-use systems. However, concerns about yield reductions persist and whether these are driven by microclimate alterations or below-ground competition for water remains unclear. In this study, we measured wind speed, air temperature, and global radiation at seven positions within a 48 m wide crop alley of a short rotation ACS in Germany with summer barley (Hordeum vulgare) and poplar (Populus nigra × P. maximowiczii and P. trichocarpa Torrey \& A. Gray) and on a treeless reference field (OF) during a particularly dry and warm year. Additionally, gravimetric soil water content and crop yield were assessed with high spatial resolution. Our results show that tree strips influenced all measured parameters. Global radiation and air temperature patterns varied dynamically with shading, while night-time air temperatures were unexpectedly highest on the OF. Wind speeds were reduced by up to 98\% near tree strips and 81\% further away. Soil water content displayed a U-shaped pattern, with higher values near tree strips, a rare observation in ACS. Crop yields in the ACS were twice as high as in the OF, despite being lower near tree strips. Yields were strongly correlated with global radiation but not with air temperature, wind speed, or soil water content. These findings provide preliminary evidence that tree presence in ACS can, under certain conditions, contribute to increased crop yields. The results suggest that ACS provide potential benefits for sustainable land-use, but further multi-year and multi-site studies are needed to validate the observed yield patterns across different environments and years, particularly under varying climatic conditions. Further research should also explore the indirect effects of microclimate modifications on soil water dynamics, including evapotranspiration.}, language = {en} } @misc{MajauraSutterluettiBoehm, author = {Majaura, Marie and Sutterl{\"u}tti, Rahel and B{\"o}hm, Christian}, title = {Tree strips reduce atmospheric evaporative demand and influence crop water use efficiency in crop alleys of a temperate alley cropping system}, series = {Agricultural water management}, volume = {328}, journal = {Agricultural water management}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {0378-3774}, doi = {10.1016/j.agwat.2026.110297}, pages = {1 -- 14}, abstract = {Agroforestry is widely recognized as a promising strategy for climate change adaptation and mitigation, partly because trees modify the microclimate and can thereby stabilize crop yields under increasing climatic variability and fluctuating water availability. However, how these microclimatic modifications influence precipitation partitioning, atmospheric evaporative demand (AED) and crop water-use efficiency (WUE) has received comparatively little research attention, particularly in temperate alley cropping systems (ACS). In this study, we analysed spatial patterns of precipitation (measured at gauge height), reference evapotranspiration (ET0) and WUE at varying distances from tree strips in a temperate ACS and an open field (OF) reference across three crops and two growing seasons. Higher precipitation amounts were frequently recorded in the ACS, particularly near tree strips, while values within the crop alley were often lowest at the centre position. ET0 was consistently lower in the ACS than in the OF and showed distinct spatial variability within the alley. WUE patterns depended strongly on the calculation approach: evapotranspiration-based WUE was generally higher at mid-alley positions than in the OF, whereas precipitation-based WUE showed comparable values between systems. Notably, these differences in evapotranspiration-based WUE occurred despite similar grain yields and were primarily driven by reduced AED rather than higher yields. Overall, our results show that tree-induced microclimatic buffering reduces AED within crop alleys and that resulting differences in WUE strongly depend on the metric used.}, language = {en} }