Copper distribution among physical and chemical fractions in a former vineyard soil

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Copper distribution among physical and chemical fractions in a former vineyard soil

L'articolo è disponibile sul sito dell'editore: www.edizioniplus.i

Monitoring and mapping soil functionality in degraded areas of organic European vineyards

Póster presentado en el 11th International Terroir Congress, celebrado en Willamette Valley, Oregon (Estados Unidos) del 10 al 14 de julio de 2016.Soil malfunctioning, caused by an improper land preparation before vine plantation and/or management, is a common problem in European vineyards. Soil malfunctioning can include: reduced contribution of the soil fauna, poor organic matter content, imbalance nutritional status, altered pH, water deficiency, soil compaction and/or scarce oxygenation. To address these problems, ReSolVe, a transnational European research project, aimed at testing the effects of selected agronomic strategies for restoring optimal soil functionality in degraded areas within organic vineyard. The project involves 8 research groups in 6 different EU countries (Italy, Spain, France, Sweden, Slovenia, and Turkey) with experts from several disciplines including soil science, ecology, microbiology, grapevine physiology, viticulture, and biometry. The experimental vineyards are situated in Italy (Chianti hills and Maremma plain, Tuscany), Spain (La Rioja), France (Bordeaux and Languedoc), and Slovenia (Primorska) for winegrapes, and in Turkey (Adana and Mersin) for tablegrapes. Three different restoring strategies have been implemented: (i) compost, (ii) green manure with winter legumes, and (iii) dry mulching with cover crops. These strategies have being tested according to their efficiency to improve i) plant and root growth; and ii) grape yield and quality; optimize iii) the quality of soil ecosystem services; and iv) the terroir effect. The first activity of the project was characterizing and mapping the degraded areas within experimental vineyards. In the work we used non-invasive technologies to characterize soil and plant status. In Spanish and Italian vineyards, the delineation of degraded areas was performed by gamma-ray spectroscopy for topsoil, RGB machine vision for canopy status and thermography for plant water status. Gamma-ray spectroscopy measured continuously the natural gamma-ray emitted from the first 30-40 cm of soil, calculating the contribution of the main radionuclides (40K, 232Th, and 238U). The spectra of gamma-ray were able to provide information about mineralogy, texture, surficial stoniness and carbonates. RGB and thermal cameras were used to assess canopy porosity, leaf area exposure and vine water status of both degraded and non-degraded areas. All soil, canopy and water status parameters were mapped.Peer Reviewe

Soil ecosystem functions in a high-density olive orchard managed by different soil conservation practices

The long-term effects of two different soil management practices, natural grass cover (NC) and conservation tillage (CT), on soil functions (carbon sequestration, habitat for organisms, and water movement and retention) were determined in a high-density, mature olive orchard (Olea europaea L. cv. Frantoio) growing in a sandy loam soil (Typic Haploxeralf) in a Mediterranean environment. Ten years after the beginning of the different soil management, soil samples were collected at 0–10 and 10–20 cm depth and at two distances from the trunk, underneath the olive canopy (UC) and in the inter-row (IR). There were no differences in fruit yield, oil yield, and yield efficiency between the two soil management systems during the 2011–2013 period. CT negatively affected soil organic carbon pools (total and humified), but only at the IR position. The distance from the plant did not significantly influence soil structure and hydrological properties, while NC treatment increased water movement and retention. Tillage reduced the microarthropod abundance, in particular Collembola and eu-edaphic forms, which were the most sensitive groups to soil perturbation. We conclude that natural grass cover was more effective than conservation tillage in maintaining or improving elements of soil functionality

Biochar persistence, priming and microbial responses to pyrolysis temperature series

Biochar and its properties can be significantly altered according to how it is produced, and this has ramifications towards how biochar behaves once added to soil. We produced biochars from corncob and miscanthus straw via different methods (slow pyrolysis, hydrothermal and flash carbonization) and temperatures to assess how carbon cycling and soil microbial communities were affected. Mineralization of biochar, its parent feedstock, and native soil organic matter were monitored using 13C natural abundance during a 1-year lab incubation. Bacterial and fungal community compositions were studied using T-RFLP and ARISA, respectively. We found that persistent biochar-C with a half-life 60 times higher than the parent feedstock can be achieved at pyrolysis temperatures of as low as 370 °C, with no further gains to be made at higher temperatures. Biochar re-applied to soil previously incubated with our highest temperature biochar mineralized faster than when applied to unamended soil. Positive priming of native SOC was observed for all amendments but subsided by the end of the incubation. Fungal and bacterial community composition of the soil-biochar mixture changed increasingly with the application of biochars produced at higher temperatures as compared to unamended soil. Those changes were significantly (P < 0.005) related to biochar properties (mainly pH and O/C) and thus were correlated to pyrolysis temperature. In conclusion, our results suggest that biochar produced at temperatures as low as 370 °C can be utilized to sequester C in soil for more than 100 years while having less impact on soil microbial activities than high-temperature biochars

The Necrobiome of Deadwood: The Life after Death

In recent decades, sustainable forest management has been increasingly recognized, promoting the diffusion of silvicultural practices aimed at considering all components of the forest system. Deadwood is an important component of the forest ecosystem. It plays a fundamental role in providing nutrients and habitats for a wide variety of saprotrophic and heterotrophic organisms and significantly contributes to soil formation and carbon storage. Deadwood is inhabited by a plethora of organisms from various kingdoms that have evolved the ability to utilize decaying organic matter. This community, consisting of both eukaryotic and prokaryotic species, can be defined as &ldquo;necrobiome&rdquo;. Through the interactions between its various members, the necrobiome influences the decay rates of deadwood and plays a crucial role in the balance between organic matter decomposition, carbon sequestration, and gas exchanges (e.g., CO2) with the atmosphere. The present work aims to provide an overview of the biodiversity and role of the microbial communities that inhabit deadwood and their possible involvement in greenhouse gas (CO2, N2O, and CH4) emissions

The Effect of Organic and Conventional Cropping Systems on CO2 Emission from Agricultural Soils: Preliminary Results

The effects of different agricultural systems on soil organic carbon content and CO2 emission are investigated in this work. In a long-term experiment a conventional system, characterized by traditional agricultural practices (as deep tillage and chemical inputs) was compared with an organic one, including green manure and organic fertilizers. Both systems have a three-year crop rotation including pea – durum wheat – tomato; the organic system is implemented with the introduction of common vetch (Vicia sativa L.) and sorghum (Sorghum vulgare bicolor) as cover crops. In the year 2006 (5 years after the experimentation beginning) was determined the soil C content and was measured the CO2 emissions from soil. The first results showed a trend of CO2 production higher in organic soils in comparison with conventional one. Among the two compared cropping systems the higher differences of CO2 emission were observed in tomato soil respect to the durum wheat and pea soils, probably due to the vetch green manuring before the tomato transplanting. These results are in agreement with the total organic carbon content and water soluble carbon (WSC), which showed the highest values in organic soil. The first observations suggest a higher biological activity and CO2 emission in organic soil than conventional one, likely due to a higher total carbon soil content