Andrea Vityi

Earth–Air Heat Exchange (EAHE) systems are an eco-friendly and energy-efficient technology as pre-heating or pre-cooling systems in civil buildings. Technically, the performance of the EAHE system is influenced by properties associated with the technology. In this paper, the focus is placed on the properties covered by the published literature to understand how they impact the efficiency of these systems. The review scrutinizes the implication of pipe properties such as the material type (steel, Polyvinyl Chloride [PVC], concrete, or high-density polyethylene), diameter and length, and depth in the context of modern building design and energy conservation. Other properties considered in this work are air velocity and the bonding of pipes with the soil. The EAHE systems’ performance is not significantly influenced by the pipe material, unlike the pipe length and diameter. It is reported that longer pipes enhance the cooling output in the EAHE system. The pipe length positively correlates with the in-pipe air temperature. An increment in the pipe diameter led to a drop in the in-pipe air temperature. An indicative report states that an increasing air flow velocity can lead to thermal losses from pipes to their surrounding soil. The addition of sand below and above the pipe enhances the thermal conductivity, just as an increase in the moisture content of the soil will contribute. There are attempts to use additives, construction waste, graphite, and fly ash as a backfill material, but with opposing economic feasibility. Construction waste could help the EAHE system to improve by 80%. A combination of graphite and fly ash as a backfill material is cost-effective. Research on the pipe material type and standards development are limited. Overall, the pipe material type and length to adopt for an EAHE system are based on the funds’ availability for the construction.

Establishing shelterbelts for field protection is one of the rediscovered agroforestry practices in Europe and Hungary. Several studies have focused on the effects of these plantations on agricultural production. Prior scholarship reveals that shelterbelts enhance the diversity of bird and insect communities but generally fail to consider herbaceous cover. Our study aimed to describe the herbaceous vegetation in shelterbelts of different origins, tree species composition, and land management. We investigated surveys in four agricultural landscapes of North West Hungary, where the intensity of the landscape transformation is different. The diversity and species composition of the herbaceous vegetation were analyzed, including plant sociology and forest affinity. Our results highlight the importance of landscape history in herbaceous flora. Shelterbelts planted on cultivated without an immediate connection to former woody vegetation soil are not appropriate for the appearance of forest-related herbaceous species, regardless of tree species composition or the extent of the shelterbelt. On the contrary, the remnants of former woody vegetation are refuges for those herbaceous species that are very slow at colonizing new plantations. These findings expose that protecting existing woody areas is an essential task of agricultural land management.