Interannual climate variability determines the efficiency of functional recovery in dry Mediterranean abandoned vineyards

Abstract

European abandoned lands have been increasing in recent decades, and this is occurring in a climate change scenario in which the consequences of their interactions are still little known. We tested the hypothesis that the functionality of abandoned lands responds differently to year‐to‐year climate variations depending on the time since the cessation of agricultural activity. We constructed a chronosequence in Mediterranean abandoned vineyards at six different years of abandonment in 2016 (1, 3, 7, 11, 25, 40), in a current vineyard and in land not dedicated to vineyards. Soil total organic carbon (TOC), total nitrogen (TN) and available nutrients, enzyme activities relating to the main macronutrient cycles and plant‐community attributes were studied at 24 sites over three consecutive years. A total of 144 samplings were performed. TOC, TN, most enzyme activities and plant species density increased throughout the chronosequence, although interannual climate variability also had a significant influence. The extreme drought event increased the activity of enzymes related to the carbon (C) and nitrogen (N) cycle, as well as the stock of TOC after a subsequent decrease in TOC when environmental conditions became favourable. In contrast, plant species density and the cover of certain plant functional traits such as mycorrhizal symbiotic plants (Cistaceae) and N‐fixers (Fabaceae) decreased significantly. Our results also demonstrated that extreme drought events had a higher negative impact on lands that had been abandoned for longer. We therefore conclude that extreme drought events damage the functionality of Mediterranean abandoned agrosystems, thus affecting all its compartments and jeopardising its functionality.

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

“…In our study this role corresponded largely to lavender (Lavandula pedunculata), which accounts for the importance of terpenoid accumulators (typically in Lamiaceae species) in late-stage succession. Cover of N-fixers, whose direction of change -according to our results -was dependent on the sampling year, could be used as an indicator of interannual climate variability since their abundance decreases in extreme drought (Quintana et al 2021). 1 and 2; colour intensity indicates sampling year: pale for 2016 and dark for 2020.…”

“…Soil was sampled at the same time as the vegetation was relevéd. Soil was collected within the contiguous 1 × 1 m quadrat outside the 1m 2 quadrat established for vegetation sampling as a permanent site (Quintana et al 2021). Soil samples were taken using two cores with a diameter of 5 cm from the top 0 − 5 cm in each quadrat.…”

Effects of solar park construction and solar panels on soil quality, microclimate, CO2 effluxes, and vegetation under a Mediterranean climate

“…Previous vineyard management, in particular, soil tillage, may have severely decreased microbial biomass resulting in low microbial activity. Five years of abandonment was probably not sufficient to entirely reestablish microbial communities (Quintana et al, 2021). Despite the reduction of microbial properties in abandoned vineyards and solar park soils, the microbiological soil quality index (mSiQ) was not significantly different between land cover types (Figure 2c).…”

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).…”