Four Decades of Soil Fertility Change in Turkey’s Thrace Region: Rising Acidity, Phosphorus Accumulation, and Persistent Organic Matter Depletion
Year: 2026
Type: article
Abstract: Long-term monitoring of soil fertility parameters is critical for evaluating the sustainability of agricultural practices and their environmental impacts. This study investigates soil pH, organic matter, and available phosphorus dynamics over a 34-year period in Turkey’s Thrace Region (Edirne, Kırklareli, Tekirdağ). For each province, soils were classified using the same threshold intervals in 1984 and 2018, and the proportion of samples in each class was compared between years (reported as percentages and percentage-point changes). The results show a marked shift toward soil acidification, with strongly acidic soils (pH < 4.5) emerging for the first time, now accounting for up to 3.1% of sampled soils. The share of neutral soils declined substantially, from 55.5% to 36.7% in Edirne. Soil organic matter levels remained critically low throughout the region, with over 80% of soils containing less than 20 g kg-1organic matter. Meanwhile, excessive phosphorus accumulation was observed: over 70% of soils were classified as “high” or “very high” in available P, indicating long-term over-application of phosphate fertilizers. These changes reflect the cumulative impact of conventional fertilization practices and insufficient organic matter inputs. The findings highlight the urgent need for corrective strategies, such as lime application, balanced fertilization, and organic amendments, to restore soil health and sustain agricultural productivity in the Thrace Region. Highlights: Soil acidification increased across the Thrace Region between 1984 and 2018. Strongly acidic soils emerged in recent surveys, although they were absent in 1984. Soil organic matter remained critically low in most agricultural soils of the region. Available phosphorus accumulated markedly, indicating long-term overuse of phosphate fertilizers. Balanced fertilization, liming, and organic amendments are required to restore soil fertility.
DOI: 10.48162/rev.39.219
Language: English
Subfield: Soil Science
Domain: Life Sciences
SDGs: Life on land, Zero hunger
Open Access status: gold
Estimated APC paid: $300
OpenAlex ID: W7166308544