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Europe experienced unprecedented droughts during the years 2018, 2019, and 2020. In the course of climate change, it is expected that such drought events will occur more frequently so that agriculture needs to adapt to droughts. Hemp (Cannabis sativa L.) has been promoted as an adaptation to water limited conditions. Hemp delivers biomass as a raw material to a variety of different value chains, such as fibers and textiles, house construction, chemicals, or food applications. Hemp develops a deep root system, which enables it to cover its water demand even during longer dry periods. This may lead to an over exploitation of soil moisture of deeper soil layers or of the groundwater in the long-term. Against this background, this study assessed the water consumption of hemp in Northeastern Germany (region Uckermark) during the growing seasons 2018–2022. The Penman Monteith approach was used to calculate the water consumption, whereby the remote sensing based S-SEBI approach was employed, with Landsat satellite images as input data, to feed crop coefficients into those calculations. The water consumption of hemp ranged from 310 to 407 mm over the growing seasons 2018–2022, while stem yields were 9 t ha-1 (except 2018 with 7.8 t ha-1). This water consumption did exceed the precipitation during the growing seasons, but did not exceed the total precipitation of the given hydrological years so that growing hemp does not constitute an over-exploitation of water. Instead, hemp taps the soil moisture that has infiltrated into the soil during autumn and winter. This makes hemp a crop well suited for an adaptation to a drier, hotter, and more variable climate.

Purpose: This study investigated the water consumption (crop evapotranspiration) of industrial hemp on a newly established hemp field in Aqmola Region of Northern Kazakhstan. Methodology: The water consumption of hemp was investigated through direct measurements of the sapflow movement during the second half of the growing season 2021. These sapflow data yielded data on the water consumption. The water consumption of the first part of the growing season was assessed through the Penman-Monteith approach by FAO. Findings: The water consumption of hemp was 353 mm over the growing season at a stem yield of 10 t/ha. Under the water supply conditions of the study site, hemp offers higher yields than grasslands or grains. Originality/value: This is the first study that revealed data on water consumption of hemp for the region Central Asia as a potential raw material plant for bioeconomy.

Maize cropping systems, the world's most important cropping systems in terms of production volume, are responsible for many environmental problems, such as soil degradation and erosion. This calls for sustainable practises that enable environment-friendly production while generating sufficient output, as farmers and consumers worldwide depend on adequate yields. Agroforestry can offer solutions to both of these pressing concerns—food insecurity and adverse environmental impacts of intensive maize cultivation. This meta-analysis investigated the effects of agroforestry on maize (Zea mays L.) grain yield under different environmental and management regimes on a global scale. It is based on 1,215 pairwise data entries from 95 peer-reviewed studies. Overall, agroforestry increased median maize yields by 0.24 Mg ha−1 (7%) compared to tree/hedgerow-free maize monocultures. In subtropical and tropical regions, the median yield increment under agroforestry was 0.30 Mg ha−1 (+16%), and the best results were achieved using broadleaved trees (+0.42 Mg ha−1, +53%), especially N-fixing tree species (+0.56 Mg ha−1, +60%). Maize yields responded very well to the addition of tree prunings to the soil of the maize crop (+0.48 Mg ha−1, +24%). Rotating maize with other crops was beneficial if the intermediate crop is able to fix atmospheric N (+0.28 Mg ha−1, +13%). We found that hedgerow planting densities of at least 5,000 woody perennials ha−1 are required for the positive impacts of agroforestry on maize yields to take effect, and these effects increased with both tree age (+1.17 Mg ha−1, +48% under trees 11–15 years of age) and time under agroforestry (+0.85 Mg ha−1, 81% in response to >15 continuous maize seasons under agroforestry). In addition, they were particularly pronounced on sandy soils (+0.46 Mg ha−1, +23%), moderately acidic soils of pH 5–6 (+0.67 Mg ha−1, +35%), soils with