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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.

Central Asia is largely dominated by drylands; so agriculture depends on irrigation in most parts of the region, which results in large scale water withdrawal, mainly from rivers, and, consequently, water scarcity. Climate change is expected to aggravate such water shortages as river flows are predicted to be substantially reduced during the second half of this century, which will put additional strain on irrigated agriculture. Tree wind breaks are one option to reduce water consumption in irrigated agriculture, add to farm income, and are therefore prioritized by government policies. Still, many farmers fear that tree wind breaks may compromise crop yields and income. Therefore, based on preceding studies this paper investigates the water productivity – net present value by unit of water consumed – of tree wind break systems of single row tree rows combined with cotton (Gossypium hirsutum L.), corn (Zea mays L.), and rice (Oryza sativa L.) compared with those crops under open field conditions. The tree wind break systems attained higher water productivities across all crops, different discount rates, tree ages of tree wind breaks, and varying crop yields. Tree wind break systems at 200 m spacing attained higher water productivities than those at 1000 m spacing. In conclusion, tree wind breaks can be inserted into the irrigated agriculture as an additional source of farm income, source for wood resources, and help reducing overall water consumption in irrigated agriculture. Simple tree lines are put forward, as multiple tree rows have been shown not to attain financial gains and save less water than the single tree lines.

Agriculture in Central Asia largely relies on irrigation. The water is withdrawn from the rivers of the region, which predominantly originate from snowfields and glaciers. Due to global warming, these water resources are expected to decline substantially, resulting in an aggravation of already existing water scarcity. Tree shelterbelt systems, as the most prominent practice of agroforestry in Central Asia, are reported to help to reduce water consumption in irrigated agriculture. Populus. alba is one of the most important shelterbelt trees in Central Asia. Though, studies about water consumption of shelterbelts are lacking. Therefore, the objectives of this study are to (1) investigate water consumption of Populus alba trees in a shelterbelt system in Central Asia and (2) analyze the influence of local climatic conditions on the sap flow of such a shelterbelt. Tree water consumption was assessed through sap flow measurements on three trees in a crop shelterbelt system in the Chui Valley in South Eastern Kazakhstan during June and July 2016. The average daily water consumption was 187.6 l/d, 44.8 l/d, and 160 l/d for the trees, respectively. These results were extrapolated for a representative shelterbelt section. Water consumption of that section was 7.8 mm/d, while average ETo was 5.3 mm/d. Considerable influences of water vapor saturation deficit, air temperature and relative humidity on the sap flow could be observed. Solar radiation played a role, too, whereas little or no influence of wind speed on tree water consumption was found.

Kyrgyzstan is home to one of the largest areas of natural walnut forest in the world. These forests support significant genetic diversity of many important ancestral strains of fruit and nut tree species. The walnuts from those forests are a major source of cash income for many households in that region. Most of the walnut forests are overgrazed, which effectively hinders natural rejuvenation. This has resulted in overaged and degraded forests. Currently, tree cutting for timber is forbidden under a moratorium. In some instances, walnut trees grow in agroforestry systems together with potato and corn as annual crops or apples and berries, alongside hay. Reforestation and afforestation in the walnut forest region is imperative to secure walnut harvests and associated incomes once the existing trees start bearing fewer nuts. The objective of this study was to analyze the economic performance of a range of representative combinations of annual crops, berries, and fast-bearing fruit trees in reforestation and afforestation plots. This included hypothetical timber utilization in order to be able to bridge the income gap until newly planted walnut trees bear nuts. Data were based on semistructured household and expert interviews. In all plots there was grassy vegetation, which was harvested for hay. In some of the plots, corn and potatoes were grown as annual crops. Additionally, in part of the plots apple and berries were grown next to walnuts. The net present value of the farming systems for a 20-year period was highest for the 2 systems that included hypothetical timber utilization. Walnut and haymaking performed worst, with a negative net present value. All non-timber systems yielded an income gap until around year 10, when walnut trees begin to fruit.

Across Central Asia, agriculture largely depends on irrigation due to arid and semi-arid climatic conditions. Water is abstracted from rivers, which are largely fed by glacier melt. In the course of climate change, glaciers melt down so that a reduced glacier volume and reduced water runoffs are expected to be available for irrigation. Tree wind breaks are one option to reduce water consumption in irrigated agriculture and build resilience against climate change. This paper therefore assesses the water consumption of major crops in Kyrgyzstan and adjacent areas, i.e., cotton (Gossypium hirsutum L.), wheat (Triticum aestivum L.), corn (Zea mays L.), rice (Oryza sativa L.), potato (Solanum tuberosum L.), and barley (Hordeum vulgare L.) in combination with tree wind breaks. Crop water consumption was assessed through the Penman Monteith approach. Tree wind break types investigated were single rows from poplars (Populus spec.) and multiple rows with understory vegetation by elm (Ulmus minor L.) and poplar, respectively. Tree water consumption was determined through sapflow measurements. The seasonal reference evapotranspiration (ETo) for field crops was 876–995 mm without wind breaks and dropped to less than half through multiple row wind breaks with understory vegetation (50 m spacing). Tree water consumption was 1125–1558 mm for poplar and 435 mm for elm. Among the wind break crop systems, elm wind breaks resulted in the highest reductions of water consumption, followed by single row poplars, at spacing of 50 and 100 m, respectively. However, elm grows much slower than poplar, so poplars might be more attractive for farmers. Furthermore, single row wind breaks might by much easier to be integrated into the agrarian landscape as they consume less space.

Assessments of climate change impacts on forests and their vitality are essential for semi-arid environments such as Central Asia, where the mountain regions belong to the globally important biodiversity hotspots. Alterations in species distribution or drought-induced tree mortality might not only result in a loss of biodiversity but also in a loss of other ecosystem services. Here, we evaluate spatial trends and patterns of the growth-climate relationship in a tree-ring network comprising 33 juniper sites from the northern Pamir-Alay and Tien Shan mountain ranges in eastern Uzbekistan and across Kyrgyzstan for the common period 1935-2011. Junipers growing at lower elevations are sensitive to summer drought, which has increased in intensity during the studied period. At higher elevations, juniper growth, previously favored by warm summer temperatures, has in the recent few decades become negatively affected by increasing summer aridity. Moreover, response shifts are observed during all seasons. Rising temperatures and alterations in precipitation patterns during the past eight decades can account for the observed increase in drought stress of junipers at all altitudes. The implications of our findings are vital for the application of adequate long-term measures of ecosystem conservation, but also for paleo-climatic approaches and coupled climate-vegetation model simulations for Central Asia.