82 research outputs found
Technosols Development in an Abandoned Mining Area and Environmental Risk Assessment
No full textThe study of Technosols development, spatial distribution and physicochemical characteristics is becoming more and more important in the Anthropocene Era. The aim of the present study was to assess soil features and potential heavy metal release risk of soils developed on different mine tailing types after the waste disposal derived from mining activity in Central Italy. Soils were analyzed for their morphological, physical and chemical properties, and a chemical sequential extraction of heavy metals was performed. The investigated soils were classified as Technosols toxic having in some layer within 50 cm of the soil surface inorganic materials with high concentrations of toxic elements. Our findings showed that the bioavailability of potentially toxic element concentrations in the soil changed according to the origin of the mine tailing. However, because of the acidic pH, there is a serious risk of metals leaching which was reduced where the soil organic matter content was higher
The conversion of abandoned chestnut forests to managed ones does not affect the soil chemical properties and improves the soil microbial biomass activity
No full textRecently, several hectares of abandoned chestnut forests (ACF) were recovered into chestnut
stands for nut or timber production; however, the effects of such practice on soil mineral horizon
properties are unknown. This work aimed to (1) identify the better chestnut forest management
to maintain or to improve the soil properties during the ACF recovery, and (2) give an insight into
the effect of unmanaged to managed forest conversion on soil properties, taking in consideration
sweet chestnut (Castanea sativa Mill.) forest ecosystems. The investigation was conducted in an
experimental chestnut (Castanea sativa Mill.) forest located in the northern part of the Apennine chain
(Italy). We identified an ACF, a chestnut forest for wood production (WCF), and chestnut forests
for nut production with a tree density of 98 and 120 plants ha-1 (NCFL and NCFH, respectively).
WCF, NCFL and NCFH stands are the result of the ACF recovery carried out in 2004. After 15 years
since the ACF recovery, generally, the effects on the main soil chemical properties were negligible.
Some differences occurred for the water-soluble organic carbon (WSOC) and microbial biomass and
its activity. NCFL showed the highest WSOC content in the uppermost soil horizon likely due to
higher amount of roots which are source of labile organic compounds. The higher WSOC amount
might explain the greatest amount of microbial biomass in the A horizon of NCFL. Furthermore,
the microbial biomass harboring in the A horizon of NCFL has also shown both a better C use
efficiency and a larger soil organic carbon immobilization in the microbial biomass itself. Our data
would indicate that the ACF recovery into pure chestnut forests did not have negative impacts on soil
chemical and biochemical properties, though chestnut stands for nut production with a low plant
density are the most suitable ones
Zea mays L. Grain: Increase in Nutraceutical and Antioxidant Properties Due to Se Fortification in Low and High Water Regimes
No full textThis work aimed to investigate the effect of selenium (Se) and irrigation on the grain yield, on the forms of Se, phenols, carotenes and on some antioxidant activities of maize (Zea mays L.) grains. To reach this goal, a two-year experiment was undertaken. Maize was fertigated with sodium selenite at the rate of 200 g Se ha−1 and grown under two water regimes. While the irrigation did not show a clear effect on the selected parameters, Se fertigation increased the contents of inorganic and organic Se forms, xanthophyll, and salicylic acid. Furthermore, while Se fertigation decreased the hydroxycinnamic acids content, generally higher antioxidant activities were found in Se treated grains than in the control. These findings suggest that, Se fertigation increases most of the nutraceutical values of maize grains which, therefore, might improve the humans and livestock health and could increase the maize grain shelf life and its by-products
Soil organic carbon stock assessment in forest ecosystems through pedogenic horizons and fixed depth layers sampling: What's the best one?
No full textIn soil organic carbon (SOC) survey, the role of sampling approach is crucial andshould not be underestimated. In this sense, the appropriateness of soil sampling bypedogenic horizons (PGH) and fixed depth layers (FDL) in forest is still a field ofdebate. The present work aimed to: (a) study the spatial variability of SOC concentra-tions and C stocks through PGH and FDL samplings in uneven-aged sweet chestnut,European beech and Norway spruce forests of the Apennine chain (Italy); (b) clarifythe major advantages and drawbacks of sampling by PGH and FDL. In a representa-tive area (1818 m) of each forest, a soil profile was investigated and eight addi-tional sampling points were selected. The sampling was performed both by PGH andFDL (0–15 and 15–30 cm). For each forest, no SOC content and C stock differencesin 0–30 cm soil depth were found between PGH (58.8 ± 5.3 g kg1and 103±7gha1, respectively) and FDL (52.7 ± 4.3 g kg1and 117 ± 9 Mg ha1, respec-tively) sampling. However, under Norway spruce, PGH sampling pointed-out that Cwas mainly stored in Oe and Oa horizons (51.1 vs. 146 Mg ha1in the 0–30 cmlayer). The higher coefficient of variation obtained when soil horizons were consid-ered (from 19.2% to 72.8% for PGH and from 16.5% to 25.7% for FDL) suggestedthat PGH sampling preserved the information about the spatial variability within anecosystem. The information loss about SOC vertical and spatial distribution wouldindicate the inability of FDL sampling to support decision-making plans addressed forsustainable use of soil resourc
GIS-Based Geopedological Approach for Assessing Land Suitability for Chestnut (Castanea sativa Mill.) Groves for Fruit Production
No full textThe identification of mountainous areas suitable for chestnut stands for fruit production (CSFP) is raising increasing interest among researchers. This work aimed to (i) identify the areas suitable for CSFP shown in a land suitability map easy to read by land planners, and (ii) propose a remote-sensing-based methodology able to identify the lands currently under cultivation for CSFP. This study was conducted using the QGIS software for the Municipality of Castel del Rio, Emilia-Romagna Region, Italy. To obtain the land suitability map, topographic, lithological, and pedological data were acquired, and the areas located between 200 and 1000 m of altitude, with north exposition, a slope < 20°, sandstone-based lithology, and soils with dystric features were selected. The currently cultivated areas for CSFP were identified through remote-sensing images of the early spring period, which were delineated and georeferenced. The findings showed that only 10% of the whole study site area can be considered suitable for CSFP. Further, most of the currently cultivated CSFP (59%) are in non-suitable areas characterised by high slope gradients. The methodology applied in this study can easily provide detailed information about the suitable areas for CSFP and the areas currently cultivated with chestnut, thus allowing accurate land-use planning and land conservation
Holm oak (Quercus ilex L.) rhizosphere affects limestone-derived soil under a multi-centennial forest
No full textBackground and Aims - The activity of roots and associated microorganisms plays a key-role in soil formation and evolution, but we lack of knowledge on the quality and extent of the “rhizosphere effect” in the different soil horizons. The aim of this study was to assess the interactions between rhizosphere processes and genetic horizons in a forest (Quercus ilex L.) soil developed from limestone. Specifically, we tested (a) if the rhizosphere effect was significant in all the horizons of the soil profiles, and (b) if the intensity of the rhizosphere effect was associated to structure, composition and activity of the microbial community. Methods - Bulk and rhizosphere soils were characterized by physical, mineralogical, chemical and biological (microbial activity and community structure) analyses. Results - Throughout the soil profile, the rhizosphere processes affected properties like particle-size distribution and soil structure, mineralogy, pH, and organic C and total P content. Conversely, amounts of exchangeable Ca, Mg and K, iron oxides, available P, and total nitrogen showed no significant change. As for the microbial community, its structure and metabolic activity differed between rhizosphere and bulk only in the core of the solum (2Bwb and 3Bwb horizons). Conclusions - The main processes controlling the intensity of the rhizosphere effect on the soil horizons were root activity, soil faunal perturbation and slope dynamics. While root activity impacted the whole soil profile, although to a lesser extent at depth, the influence of fauna and slope was confined atop the profile. It follows that long-term changes due to root activity and associated microbial community were more strongly expressed in the core of the solum, not at the surface, of this limestone-derived soil
GIS-based soil maps as tools to evaluate land capability and suitability in a coastal reclaimed area (Ravenna, northern Italy)
No full textLand capability and suitability maps are useful tools for soil resource conservation. This study aimed to build land capability and suitability maps using a multi-thematic approach by GIS in a salt-affected coastal area of Italy. Topographic, morphological, geological, pedological delineations and land cover maps, remote sensing image and climate data were acquired and the main physical and chemical properties, including electrical conductivity (EC) and available water capacity, were analysed on the soil samples collected in the study area. The acquired information were elaborated through QGIS software to obtain the land capability and suitability maps. The suitability map showed that most of the area (80%) is suitable for cultivation and, therefore, can be addressed for agricultural purposes without risk of degradation. In fact, the land capability map showed that 42% of the investigated area belongs to class I and II indicating that they can be used for a wide range of cultivations. While 44% of the investigated area clustered in class III and IV. In these latter the cultivation should be allowed to a limited range of crops due to the high sand content, which does not allow a good water retention, and due to a strong intrusion of sea water with consequent increase of the soil EC. In our study area, where agricultural productivity and environmental impact are in conflict, to classify the lands on base the land capability and suitability could help to define the best agricultural practices to apply in order to preserve soil functions
Influence of agricultural management practices on soil organic carbon stock and distribution in topsoil and subsoil as revealed by a mid-term trial
No full textCover crops and no–tillage are agricultural practices used to improve soil organic carbon (OC) sequestration, although most studies are often limited to examining only the topsoil. In this study the influence of different cropping systems (CONV – integrated management without cover crop and conventional tillage, ORG – organic management with cover and temporary intercropping crops and conventional tillage, and NOTILL – integrated management with cover crops and no–tillage) was evaluated on OC quantity and distribution in topsoil (0–20 cm), midsoil (20–40 cm), and subsoil (40–60 cm) of a 10–year wheat–maize rotation trial. A physical–chemical fractionation was performed to isolate OC among labile (water soluble and particulate OC, WEOC and POC, respectively), stable (OC in sand–size and silt– and clay–size aggregates, SSA and SCA, respectively), and resistant (NaClO oxidation) pools. Further, soil samples were characterised for13C and15N natural abundance, phenols and glomalin (GRSP) contents, and microbial activity. The soil OC stock in the 0–60 cm depth was similar for CONV, ORG and NOTILL. This was attributed to enhanced mineralisation processes promoted by the addition of N–rich fresh legume cover crop residues in ORG and NOTILL soils that exceeded the rate of OC stabilisation. However, specific contributions of the functional OC pools to the total stock and along the soil depth intervals occurred. For ORG and NOTILL, the implementation with cover crops favoured the development of a stable macrostructure and the accumulation of OC in SSAs, whereas CONV system mainly accumulated OC in SCAs. When the system was implemented with both cover crops and no–tillage, as for NOTILL, almost half of the total soil OC stock was stored in the topsoil, mostly as POC and associated with SSAs. Regardless of agricultural management, 53–68 % of the total OC stock was found in the layers below the topsoil
Soil Biochemical Indicators and Biological Fertility in Agricultural Soils: A Case Study from Northern Italy
No full textIndustrial farming without considering soil biological features could lead to soil degradation. We aimed to evaluate the biochemical properties (BPs) and biological fertility (BF) of different soils under processing tomato cultivation; estimate the BF through the calculation of a simplified BF index (BFIs); determine if the crop was affected by BP and BF. Three farms were individuated in Modena (MO), Ferrara (MEZ) and Ravenna (RA) provinces, Italy. Soil analysis included total and labile organic C, microbial biomass-C (Cmic) and microbial respiration measurements. The metabolic (qCO2), mineralization (qM) and microbial (qMIC) quotients, and BFIs were calculated. Furthermore, plant nutrient contents were determined. The low Cmic content and qMIC, and high qCO2 found in MEZ soils indicate the occurrence of stressful conditions. The high qMIC and qM, and the low qCO2 demonstrated an efficient organic carbon incorporation as Cmic in MO soils. In RA soils, the low total and labile organic C contents limited the Cmic and microbial respiration. Therefore, as confirmed by the BFIs, while MO showed the healthiest soils, RA soils had an inefficient ecophysiological energy state. However, no effects on plant nutrient contents were observed, likely because of masked by fertigation. Finally, BP monitoring is needed in order to avoid soil degradation and, in turn, crop production decline
Table_1_The Selenium Supplementation Influences Olive Tree Production and Oil Stability Against Oxidation and Can Alleviate the Water Deficiency Effects.DOCX
No full textFoliar fertilization with selenium (Se) may well be beneficial in increasing the nutritional and qualitative values of food in Se-deficient regions such as the Mediterranean Basin, and may contribute to an increase in drought resistance in plants. The present study has considered detachment force, flesh firmness, pigmentation, fresh and dry weight, and oil content of olive drupes from Se fertilized olive orchards (Olea europaea L.) under drought stress and well-watered conditions. This study has also evaluated the total Se, Se amino acid, phenol, carotenoid and chlorophyll contents of EVOO, plus its oxidative stability against oxidation. While there was no change in the ripening indexes and the production of olives generally, Se application did increase the total Se, Se methionine, phenol, and carotenoid and chlorophyll contents. The higher concentration of these (bio) chemical compounds in EVOO obtained from Se fertilized plants might well suggest enhanced antioxidant activity. Consequently, EVOO obtained from Se fertilized trees possesses a higher nutritional value and, as indicated by the greater oxidative stability against oxidation, longer shelf life. In addition, under water deficient conditions, a higher fresh olive weight corresponds to a higher level of phenol, carotenoid and chlorophyll, and the chlorophyll-to-carotenoid ratio in Se fertilized trees would appear to confirm the positive role of selenium in alleviating damage caused by drought stress conditions.</p
- …
