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Trees established in linear formations can be utilised as windbreak structures on farms as a form of agroforestry system. We present an extensive data package collected from an active berry farm located near Stellenbosch, South Africa, considering hydrological, pedological, dendrological and meteorological measurements centred around an Italian alder (Alnus cordata (Loisel.) Duby) windbreak and a blackberry (Rubus fruticosus L. Var. "Waldo") crop. Data were collected between September 2019 and June 2021. The data are available from and include the following measurements (i) meteorological variables – solar radiation, precipitation characteristics, vapour pressure deficit, air temperature, humidity, atmospheric pressure, wind speed and direction, gust speed, and lightning strikes and distance recorded at 10 min intervals; (ii) hydrological measurements – soil moisture and matric potential in two profiles at 15 min intervals alongside soil samples at various depths describing soil texture, hydraulic conductivity, and water retention parameters; (iii) soil characteristics – a soil profile description accompanied by 60 topsoil samples describing carbon, nitrogen, and exchangeable base cation concentrations, as well as potential cation exchange capacity and descriptions of soil texture; and (iv) dendrological measurements – point cloud data for the studied windbreak trees and surrounding features, cylinder models of the windbreak trees with volume and biomass data, and foliage data as a product of an existing leaf creation algorithm. The described dataset provides a multidisciplinary approach to assess the impact and interaction of windbreaks and tree structures in agroforestry landscapes, aiding future work concerning water fluxes, nutrient distribution, microclimate and carbon sequestration. The dataset, including high-resolution time series and point cloud data, offers valuable insights for managing the windbreak's influence and serves as a unique training dataset for spatial analysis (https://doi.org/10.5880/fidgeo.2023.028 ,). [ABSTRACT FROM AUTHOR]

The Western Cape in South Africa is a water-scarce region which will likely receive less rainfall and higher air temperatures under projected climate change scenarios. The integration of trees within agricultural systems provides an effective measure for improving water retention on agricultural land. Studying an established and irrigated agroforestry system (AFS) combining alder (Alnus cordata (Loisel.) Duby) as a linear windbreak with a blackberry (Rubus fructicosus L.) crop, we explore the water use dynamics of the intercrop as influenced by the windbreak element by combining methods from hydrology, soil science and forestry disciplines. Our objective is to explore whether the AFS positively impacts the water balance by combining measurement campaigns to characterise the spatial variability of various key system properties with continuous monitoring. The campaigns encompassed extensive soil sampling to determine soil characteristics (nutrient concentrations, hydraulic conductivity, texture, water retention) in the laboratory as well as terrestrial laser scans of the field site, especially of the windbreaks. The continuous measurements covered meteorological, soil water content and soil water potential observations over a 6-month period (in summer). These were applied to understand soil water dynamics during rainstorms and dry spells, including root water uptake as well as soil water storage. We recorded a total of 13 rainfall events delivering 2.5–117.6 mm of rainfall with maximum intensities of 4.1 to 82.6 mm h -1. Further analyses showed that infiltration is likely dominated by preferential flow, with root water uptake potentially occurring in two depth zones corresponding to different plant communities. While soil water content varied by depth and was influenced by physical and environmental factors, it was generally higher in the intercrop zone than within the windbreak-influenced zone. During dry spells, soil water content did not drop below the water content of the permanent wilting point (<-1500 kPa). Values corresponding to soil water tensions above 1000 kPa were recorded on several occasions; these were mitigated by irrigation and, thus, did not result in water stress. Nutrient distribution and soil physical properties differed near the windbreak in comparison to the blackberry crop, and the carbon sequestration potential is great in comparison to monoculture farming. We could demonstrate positive effects of the windbreak on the water balance and dynamics in the blackberry field site, even though questions remain as to the extent of these benefits and how they compared to disadvantageous aspects brought about by the presence of the trees (e.g. increased water usage). Irrigation did, in fact, shift the AFS from a water-limited regime to an energy-limited one. [ABSTRACT FROM AUTHOR]

Trees established in linear formations can be utilised as windbreak structures on farms as a form of agroforestry system. We present an extensive data package collected from an active berry farm located near Stellenbosch, South Africa considering hydrological, pedological, dendrological and meteorological measurements centred around an Italian alder (Alnus cordata (Loisel.) Duby) windbreak and a blackberry (Rubus fruticosus L. Var. 'Waldo') crop. Data was collected between September 2019 and June 2021. The data is available from Hassler et al. (2023) and includes: solar radiation, precipitation characteristics, vapour pressure deficit, air temperature, humidity, atmospheric pressure, wind speed and direction, gust speed, lightning strikes and distance recorded at 10 minute intervals; soil moisture and matric potential in two profiles at 15 minute intervals alongside soil samples at various depths describing soil texture, hydraulic conductivity and water retention parameters; soil profile description accompanied by 60 topsoil samples describing carbon and nitrogen and exchangeable base cation concentrations as well as potential cation exchange capacity and descriptions of soil texture; dendrological measurements present point cloud data for the study windbreak trees and surrounding features alongside cylinder models of the windbreak trees with volume and biomass data, foliage data as a product of an existing leaf creation algorithm is also given. The provided data is intended to explore the interaction between trees and crops in agroforestry landscapes. [ABSTRACT FROM AUTHOR]

The Western Cape in South Africa is a water scarce region which under forecasted climate change scenarios may receive less rainfall and higher air temperatures. The integration of trees within agricultural systems provides an effective measure for improving water retention on agricultural land. Studying an established irrigated agroforestry system (AFS) combining alder (Alnus cordata (Loisel.) Duby) as a linear windbreak with a blackberry (Rubus fructicosa L.) crop, we explore the water use dynamics of the intercrop as influenced by the windbreak element by combining methods from hydrology, soil science and forestry. We also aim to evaluate whether the proposed experimental design is sufficient to capture the water balance and the underlying controls. Due to the irrigation the AFS is no longer a water- but rather an energy-limited system. During the measurement period 13 rainfall events were recorded delivering 5.5 - 117.6 mm of rainfall with an intensity of 0.4 to 5.7 mm hr-1. Root water uptake and event analysis show infiltration to likely occur via macro-pore flow with root water uptake occurring in two depth zones corresponding to different plant communities. Soil water content varied by depth and was influenced by physical and environmental factors, but was generally higher in the intercrop zone than within the windbreak influence zone. Soil moisture did not fall below the water content at the permanent wilting point (<-1500 kPa). Values corresponding to soil water tensions above 1000 kPa were recorded on several occasions, these were mitigated by irrigation, and thus, did not result in water stress. Nutrient distribution and soil physical properties differed near the windbreak in comparison to the blackberry crop and the carbon sequestration potential is great in comparison to monoculture farming. The interdisciplinary work explored numerous aspects of AFS and acquired different perspectives, confirming hypotheses through cross-method analyses. [ABSTRACT FROM AUTHOR]

Agroforestry is often discussed as a strategy that can be used both for the adaptation to and the mitigation of climate change effects. The climate of southern Africa is predicted to be severely affected by such changes. With agriculture noted as the continent's largest economic sector, issues such as food security and land degradation are in the forefront. In the light of such concerns we review the current literature to investigate if agroforestry systems (AFS) are a suitable response to the challenges besetting traditional agricultural caused by a changing climate. The benefits bestowed by AFS are multiple, offering ecosystem services, influence over crop production and positive impacts on rural livelihoods through provisioning and income generation. Nevertheless, knowledge gaps remain. We identify outstanding questions requiring further investigation such as the interplay between trees and crops and their combination, with a discussion of potential benefits. Furthermore, we identify deficiencies in the institutional and policy frameworks that underlie the adoption and stimulus of AFS in the southern African region. We uphold the concept that AFS remains an appropriate and sustainable response for an increased resilience against a changing climate in southern Africa for the benefit of livelihoods and multiple environmental values. [ABSTRACT FROM AUTHOR]