Weed Flora Composition and Phytosociological Analysis in Olive Orchards Under Different Soil Management Practices

Abstract

Weed diversity and community dynamics in olive orchards are strongly influenced by soil management practices that alter microenvironmental conditions and resource availability within orchard ecosystems. Field investigations were conducted to evaluate weed flora composition and phytosociological characteristics in olive orchards managed under different soil management systems, including conventional tillage, reduced tillage, mulching, and cover crop practices. Weed surveys were carried out during major growth stages using quadrat-based sampling methods to determine species frequency, density, abundance, and relative importance values. A diverse assemblage of broadleaf weeds, grasses, and sedges was recorded across the studied orchards, with notable variation in species composition among management systems. Conventional tillage reduced the prevalence of perennial weeds but favored the emergence of annual species adapted to disturbed soils. In contrast, mulched and cover-cropped orchards supported greater weed diversity while suppressing the dominance of highly competitive weed species through improved soil coverage and resource competition. Phytosociological indices, including species richness, Shannon diversity index, and dominance values, revealed significant differences in weed community structure among treatments. Certain invasive and drought-tolerant species exhibited high ecological adaptability and dominance under reduced soil disturbance conditions. Seasonal fluctuations in weed populations were closely associated with soil moisture, temperature, and canopy shading within the orchards. Weed biomass accumulation and competitive interactions varied according to management intensity and ground cover characteristics. The findings demonstrate that soil management practices play a critical role in shaping weed population dynamics and ecological balance in olive production systems. Adoption of sustainable soil management strategies may contribute to suppression of problematic weeds while enhancing biodiversity and ecological stability within orchards.