# Numerical Study on Tree Belt Impact on Wind Shear on Agricultural Land
## 1 Introduction  
The tree belts play an important role in the sustainable management of agricultural landscapes, fulfilling multiple functions related to the environmental protection, improved agricultural productivity, and renewable energy support [1, 2, 3]. They are a key element in the soil erosion reduction, wind load protection, and agricultural microclimate improvements. However, scientific research often faces challenges related to quantitative modeling of their effect on the airflow, as well as the lack of empirical data for their characterization in different climatic conditions. The study in [4] focused on agroforestry as an effective strategy for sustainable agriculture and climate change mitigation, highlighting the need for integrated policies and research directions. The protective functions of tree belts, such as reducing wind speed and limiting soil erosion, have been documented by multiple authors [5, 6, 7]. Furthermore, these linear green structures modify the wind airflow, including the wind shear--a parameter that is critical for both agriculture and renewable energy systems, such as wind turbines [8, 9, 10]. According to the authors in [11], the transition to renewable energy sources, including wind power, requires strategic location planning to ensure environmental sustainability, energy efficiency, and public support. The interaction between tree belts and wind flow has been studied in detail by the authors in [12; 13; 14; 15], who highlighted the importance of these structures for wind profile modification and turbulence reduction. The interest in this aspect increases when the possibility of deploying wind turbines near the belts is considered. The authors in [16; 17] pointed out that the efficiency of wind turbines depends significantly on the uniformity and turbulence of the velocity field. On the other hand, the presence of a tree belt has a direct impact on these parameters by creating zones of reduced velocity behind the belt and accelerated airflow above its height. This interaction significantly affects the aerodynamic characteristics of the wind turbine operating characteristics [18; 19]. The authors in [20] emphasized that the alignment of tree belts perpendicular to the dominant wind direction (in their case, north-northwest) is crucial for the optimization of the protective and aerodynamic effects on the environment. This approach allows the creation of synergies between soil protection and energy efficiency gains. Traditionally, the tree belts have been used to protect soil and crops from wind loads [21; 22; 23; 24]. The authors in [25] found that these structures reduce the wind speed behind them by up to 60%, which significantly limits erosion and stabilizes the soil. Furthermore, studies in [26; 27; 28] showed that the tree belts increase soil moisture by reducing evaporation, which contributes to sustainable water resource management. However, modern research goes beyond traditional applications. The authors in [29; 30; 31] investigated the role of tree belts in modifying wind shear and aerodynamic airflow characteristics. An important contribution is the study in [32], which considered the forest farm-shelter network as a complex windbreak system. According to the analysis of the results, optimizing the spacing of the main shelterbts upholds an efficiency of over 70%, while increasing the planting area, reducing side effects, and improving mechanized tillage and farming efficiency. This highlights the need for an in-depth study of the key airflow characteristics, such as wind shear, which are critical for sustainable and efficient agroecosystem management. The wind shear, defined as the change in the wind speed with the height, plays a key role in the sustainable management of agroecosystems [33; 34]. Research in [35] highlighted the importance of atmospheric stability for the accurate assessment of wind energy resources and recommended the necessity of more in-depth research on the impact of climate change on the stability of airflows in wind farms.