Influence of soil compaction on microfungal community structure in two soil types in Bartin Province, Turkey.

Soil compaction negatively influences physical properties of soil (bulk density and pore space), and may consequently limit soil microfungi, which are significant for nutrient bioavailability. We measured microfungal community responses to compaction in a sandy loam and a clay loam soil at picnic sites. Soil bulk density increased significantly in the compacted samples. However, microfungal numbers and community composition were unrelated to changes in soil bulk density. With increases in bulk density from 1.22 to 1.37 g cm(-3) in the clay soil and from 1.38 to 1.54 g cm(-3) in the sandy loam soil, the total number of fungi declined or showed insignificant increases. In the compacted samples as well as the control sites, the most frequently occurring genera in the clay soil were Penicillium, Aspergillus, and Gliocladium. However, the most prominent feature occurring within the sandy loam soil was the exhibition of the greatest increase in the frequency of the Fusarium genus. When comparing compacted and control soils, fungal community composition corresponded more closely within each soil texture. The two microfungal soil communities, therefore, tolerated compaction. In contrast, a difference occurred in the fungal communities between the two soil textures. This is more likely due to the variability in the controlling factors of microfungal abundance and composition, such as soil characteristics, tree species, and competitive ability of fungal genera.