Soil Response to Agricultural Land Abandonment: A Case Study of a Vineyard in Northern Italy

Abstract

Agricultural land abandonment is an emerging problem in European Union (EU), and about 11% of agricultural EU land is at high risk of abandonment in the coming 10 years. Land abandonment may have both positive and negative effects in ecosystems. Due to the potential for land abandonment to increase soil fertility, the study of vegetation succession effects on soil quality is of great importance. In this study, we investigated an abandoned vineyard where, after a period of 30 years, rows and alleys were characterized by two different forms of vegetation succession: natural recolonization by trees along the rows and by herbaceous vegetation in the alleys. No-tilled alleys covered by herbaceous vegetation of a neighboring conventionally cultivated vineyard were used as a comparison. Soil samples were chemically characterized (pH, extractable element, and available and total metals), and analyzed for the determination of carbon (C) and nitrogen (N) pools; hydrolytic and phenol oxidizing (PO) enzyme activities involved in C, N, and phosphorus (P) cycles; and the enzyme ratios. Results highlighted that natural recolonization by trees increased the organic C and N soil pools by 58% and 34%, respectively, compared to the natural recolonization by herbaceous vegetation. Moreover, natural recolonization by trees reduced β-glucosidase by 79%, urease by 100%, alkaline phosphastase by 98%, acid phosphatase specific hydrolytic activities by 50%, and catechol oxidase and laccase specific oxidative activities by 127% and 119%, respectively, compared to the renaturalization by herbaceous vegetation. In addition, the natural recolonization by trees reduced the C (βglu):C (PO) enzymes ratio by 16% compared to that of the conventional vineyard. Comparing the natural recolonization by herbaceous vegetation with that of the conventional vineyard revealed little significant difference (15% of the measured and calculated parameters); in particular, PO activities significantly decreased in the renaturalized vineyard with herbaceous vegetation by 49% (catechol oxidase) and 52% (laccase), and the C (βglu):C (PO) enzyme ratio showed a reduction (−11%) in the vineyard naturally recolonized by herbaceous vegetation compared to the conventional vineyard. This highlights that the type of vegetation succession that takes place after land abandonment may have a significant impact in terms of soil fertility and C accrual potential. These results help to focus attention on the practices used in agro-forestry that should be adopted in abandoned agro-ecosystems to increase their biodiversity, soil C stock, and soil quality, because these indicators are affected by the type of vegetative coverage.

Mediterranean grassland succession as an indicator of changes in ecosystem biodiversity and functionality

“…Vineyard abandonment drives an increase in the activities of soil hydrolytic enzymes such as PHOS, and reduces oxidative enzyme activities (Sciubba et al 2021). This is reinforced by our results, since a higher phosphatase activity was found in soils in late-stage grasslands, and this enzyme has a close relationship with the soil organic fraction in semiarid ecosystems (García and Hernández 1997;Jiang et al 2009).…”

“…This enzyme controls the S cycle in the soil (Chen et al 2016) and its increased activity in soils of late-stage grasslands may be connected to the decline in available S from the active vineyard -in which sulphur compounds are commonly added to control fungal vine pests -to meet the requirements of living organisms for this nutrient. Contradictory responses have been reported for urease activity in the secondary succession, from an increase (Haripal and Saoo 2013) to a decrease (Sciubba et al 2021). Our results showed that urease activity is linkable to the sampling year and directly to the cover of N-fixers and silica accumulators.…”

Degradation of traditional vineyards in Slovakia by abandonment and soil erosion: A case‐study of Vráble

“…For example, the transition from initially higher erosion rates following abandonment to lower rates following vegetation recovery has been observed in Eastern Spain (Cerdà et al, 2018) and Germany (Seeger et al, 2019). Decreased erosion rates were observed in vineyards in Northern Italy (Sciubba et al, 2021) and central (Quintana et al, 2021) and northeastern Spain (Dunjó et al, 2003) following abandonment. In addition, vineyard abandonment is thought to have positive influences on biodiversity (Plieninger et al, 2014; Vlachovičová & Špulerová, 2022).…”

Relationship among Soil Biophysicochemical Properties, Agricultural Practices and Climate Factors Influencing Soil Phosphatase Activity in Agricultural Land

“…Furthermore, a meta-analysis made by Margalef et al [40] has shown that invasive plant species can also increase ACP and ALP activity compared to native species, potentially due to differences in li er quality or quantity and related effects of changes in soil chemistry on microbial communities. On the other hand, the conversion of intensively managed agricultural land back to grassland and forest systems, using native plant species [127,133,134], improves the supply of organic matter, enhancing APase activity, especially ACP [135]. Furthermore, a meta-analysis made by Margalef et al [40] has shown that invasive plant species can also increase ACP and ALP activity compared to native species, potentially due to differences in litter quality or quantity and related effects of changes in soil chemistry on microbial communities.…”