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Hedgerows supply multiple ecosystem services in agricultural landscapes and have been advocated to provide a relevant carbon sink for climate change mitigation. Using a space-for-time approach, we investigated carbon sequestration and fractionation in soils beneath hedgerows 1 to 70 yr after planting on cultivated land in the humid continental climate of Eastern Austria. We sampled 54 pairs of hedgerow and adjacent cultivated soil volumetrically to 40 cm depth and analysed them for bulk soil (< 2 mm) mass, SOC fractions of differential stability and related soil properties. Total SOC stocks to 40 cm depth increased significantly (p < 0.05) by 34.7 ± 4.70 Mg C ha−1 to 119 ± 6.77 Mg C ha−1 beneath 31–70 yr old hedgerows, and by 15.6 ± 5.94 Mg C ha−1 to 106 ± 8.98 Mg C ha−1 beneath 1–30 yr old hedgerows. Carbon sequestration was limited to the organic and mineral topsoil layer (0–20 cm), SOC changes (ΔSOC) at 20–40 cm depth were small and insignificant (p < 0.05). Linear regression of ΔSOC on hedgerow age (1–70 yr) yields a mean SOC sequestration rate of 0.65 ± 0.10 Mg ha−1 yr−1 down to 40 cm depth. Combining our data with published work we found hedgerow age explaining ∼65 % of the variation of ΔSOC in topsoils, and ∼68 % in shallow subsoils; ΔSOC increases with hedgerow age in topsoils, but declines in subsoils. Annual sequestration rates decline with hedgerow age in both soil layers. Up to 30 years after conversion, SOC is preferably sequestered in labile particulate organic matter (POM; > 20 µm), and stabilised in the mineral-associated organic matter (MAOM; < 20 µm fraction) thereafter. In the bulk soil and MAOM fraction, SOC strongly increases with oxalate-extractable Al (Alo). We conclude that SOC sequestration beneath hedgerows offers a relevant CO2 sequestration potential which is mainly limited to topsoils and primarily controlled by hedgerow age and Alo.

Copper-based fungicides have been used for a long time in viticulture and have accumulated in many vineyard soils. In this study, incrementing Cu(OH)2-based fungicide application from 0.05 to 5 g Cu kg−1 on two agricultural soils (an acidic sandy loam (L, pH 4.95) and an alkaline silt loam (D, pH 7.45)) resulted in 5 times more mobile Cu in the acidic soil. The most sensitive parameters of alfalfa (Medicago sativa) growing in these soils were the root nodule number, decreasing to 34% and 15% of the control at 0.1 g Cu kg−1 in soil L and at 1.5 g Cu kg−1 in soil D, respectively, as well as the nodule biomass, decreasing to 25% and 27% at 0.5 g Cu kg−1 in soil L and at 1.5 g Cu kg−1 in soil D, respectively. However, the enzymatic N2-fixation was not directly affected by Cu in spite of the presence of Cu in the meristem and the zone of effective N2-fixation, as illustrated by chemical imaging. The strongly different responses observed in the two tested soils reflect the higher buffering capacity of the alkaline silt loam and showed that Cu mitigation and remediation strategies should especially target vineyards with acidic, sandy soils.

Policies for restoring soil health and mitigating climate change require information on soil organic carbon (SOC) stocks and their spatial and temporal variation, and related sequestration potentials. Using the province of Lower Austria as environmentally diverse model region, we present a detailed analysis of SOC stocks, saturation potentials and deficits along with SOC monitoring data for the past three decades. Using the provinces soil database (sampling 1991) we estimated the saturation potential for mineral-protected C (Csat) by boundary line regression to the particle fraction

This work aimed to investigate the metal accumulation characteristics as well as biogeochemical changes in the rhizosphere and root foraging strategies of this plant species. Previous reports suggested that Noccaea rotundifolia ssp. cepaeifolia is a Zn, Cd and Pb hyperaccumulator. We used hydroponic, rhizobox and split-pot experiments for studying metal accumulation and related rhizosphere processes. Although this species accumulated up to 1250 mg Pb kg−1 and 27,000 mg Zn kg−1 in shoots, translocation factors

Reliable data on K fixation in soils are of agronomic interest in paddy rice production. Considering the factors flooding time and K concentration, we evaluated fixation characteristics of K-depleted paddy soils of northern Iran using an adopted method to assess K fixation in flooded conditions. Potassium fixation in 68 topsoils (i.e. 0–30 cm) from paddy fields of the Mazandaran and Guilan provinces ranged between ~48 and ~700 mg K kg−1 soil with the maximum occurring within 30 days of flooding. These data indicate that NH4OAc-extractable, readily-available K may be below the critical level in ~220,000 ha of the paddy rice cultivated areas in the two provinces. Clay content, CEC and NH4OAc-extractable K in air-dried soil can predict 73.2% of the variation in K fixation, with K fixation increasing with clay content and CEC. The fact that the K fixation percentage remained unchanged in the range of 39.2–314 mg K added kg−1 soil shows, that large amounts of K are likely be needed to restore K fertility. These may be added in portions over several years. After restoring the K fertility in the soils, K outputs have to be balanced continuously by K fertilization.