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... Zinc (Zn) still represents an important health problem in developing countries, caused mainly by inadequate dietary intake. A large consumption of cereal‐based foods with small concentrations and low bioavailability of Zn is the major reason behind this problem. Modern cultivars of cereals have inherently very small concentrations of Zn and cannot meet the human need for Zn. Today, up to 50% of wh ...
... The fate of carbon (C) in grassland soils is of particular interest since the vast majority in grassland ecosystems is stored below ground and respiratory C-release from soils is a major component of the global C balance. The use of ¹³C-depleted CO₂ in a 10-year free-air carbon dioxide enrichment (FACE) experiment, gave a unique opportunity to study the turnover of the C sequestered during this ex ...
... Quantifying soil water storage is important for plant growth and agricultural production. This is particularly important in sandy soils because they are widely cultivated and prone to drought. We investigated the effect of soil organic carbon (SOC), soil texture and gravel content on soil moisture characteristics in sandy soils. Soil moisture characteristics were analysed using standard soil physi ...
... There are still considerable uncertainties about soil functioning in semi‐arid Mediterranean ecosystems. Hence, studies that have focused on Juniperus species in thermophilic Mediterranean woodlands are practically non‐existent. This study provides a survey of the effects of (i) woodland maturity (mature and young woodlands), (ii) vegetation cover (Juniperus thurifera L. trees, Rosmarinus officina ...
... The decomposition of soil organic matter, as an essential part of nutrient cycling, has a crucial role in maintaining soil fertility and the regulation of climate. This function of the soil is likely to be affected by extreme weather events that are expected to be more frequent and severe in the future. We conducted an experiment from March 2014 to March 2015 to test the effects of extreme drought ...
... Information about soil VOC inventories and exchange rates in different soils is very scarce. Seasonality of soil VOC exchange rates is also largely unknown, despite the increasing interest in some soil volatile compounds, such as monoterpenes, because of their important role in soil ecology. We aimed to explore and quantify soil VOC exchange rates in a Mediterranean shrubland and their seasonality ...
allophanic soils; carbon; contact angle; correlation; drought; islands; land use; nitrogen content; pastures; soil density; soil surveys; soil water; soil water content; summer; water content; New Zealand
Abstract:
... We conducted a survey of the occurrence of soil water repellency (SWR) in the top 40 mm of soils across 50 sites under pastoral land use in the North Island of New Zealand. The sites represented ten soil orders and covered five classes of proneness to drought. We found at least a moderate persistence of SWR in 35 out of 50 sites (70%) in summer 2009/2010 and a moderate potential persistence of SWR ...
Cambisols; Fluvisols; carbon; carbonates; charcoal; clay; drought; glaciation; humid zones; humus; iron oxides; magnetic properties; mineral content; playas; soil formation; stable isotopes; weathering; Mexico; Wisconsin
Abstract:
... Red palaeosols of the late Pleistocene‐early Holocene, both buried and non‐buried, were studied recently in Sonora (NW Mexico) to reconstruct their pedogenesis as well as the palaeoenvironmental conditions. The alluvial palaeosol‐sedimentary sequence of the La Playa archaeological site is a key locality for the buried San Rafael palaeosol, which exhibits a 2Ah‐2Bw‐2BCk‐3Bgk profile and was defined ...
deforestation; drought; fungi; labile carbon; land use change; microbial biomass; phospholipid fatty acids; rain forests; soil quality; total nitrogen
Abstract:
... Tropical and subtropical ecosystems are widely affected by the expansion of agriculture over pristine lands. Despite research efforts, knowledge of the impact of land‐use change on soil is still limited by intrinsic variability, inconsistent results and inadequate replication. This study aimed to better understand the consequences of land‐use change by focusing on long‐term effects on both soil bi ...
Pinus halepensis; Pistacia lentiscus; bacteria; carbon; carbon nitrogen ratio; chemical analysis; coasts; drought; drying; environmental factors; enzyme activity; fungi; heat; lignocellulases; microbial activity; microbial biomass; microbial communities; nuclear magnetic resonance spectroscopy; stable isotopes; water holding capacity; water stress; Mediterranean region
Abstract:
... Warming and disturbance of precipitation dynamics are expected in the Mediterranean basin, resulting in longer, more intense drought and heat waves. Here we investigated how litter microbial functioning and responses to stress may be shaped by coastal environmental conditions, and whether this depends on litter type (Pinus halepensis, Pistacia lentiscus and their admixture). Mesocosms of monospeci ...
... If a dry soil is wetted it can produce a large flush of nitrous oxide (N₂O), which can be 10 times above the background rate, this phenomenon is called a hot moment. However, there is uncertainty in the literature regarding the mechanisms that cause hot moments. Therefore, this study aimed to induce two different hot moments on soil cores to investigate changes in nitrogen (N) cycling functional g ...
... Extended drought periods followed by heavy rainfall may increase in many regions of the Earth, but the consequences for the quality of soil organic matter and soil microbial communities are poorly understood. Here, we investigated the effect of repeated drying and re-wetting on microbial communities and the quality of particulate and dissolved organic matter in a Haplic Podzol from a Norway spruce ...
... Climate change has altered global precipitation regimes in terms of intensity and frequency of drought stress and, consequently, it is likely to affect soil moisture and soil aggregation. However, we know little about the effects of drought on soil aggregate size, distribution and stability, and how that affects carbon sequestration. A drought manipulation experiment was conducted by throughfall e ...
Dystroxerepts; climate change; community structure; drought; genes; rain; shrublands; soil bacteria; species diversity; ultraviolet radiation
Abstract:
... Enhanced UV radiation levels and decreased rainfall in Mediterranean terrestrial ecosystems due to climate change might impact soil bacterial communities, significantly altering their structure and affecting biogeochemical cycles. The aim of this study was to evaluate the effect of UV‐B and UV‐A radiation on soil bacterial richness, abundance and community composition in a Typic Dystroxerept of Me ...
... Grassed waterways are used to mitigate the offsite transport of sediment generated by soil erosion. This study used a novel trait‐based ranking approach as a method to screen potential candidate grass monocultures and mixes based on their theoretical performance in reducing (a) detachment via rainsplash, (b) detachment via scouring due to concentrated flow and (c) sediment transport and deposition ...
... Blanket-bog peats, mapped as the Winter Hill and Crowdy associations by the Soil Survey of England and Wales, are an oceanic manifestation of the ombrotrophic 'raised-bog' (Hochmoor) peats that cover large tracts in the boreal zone of the northern hemisphere. This paper examines monthly analyses from 1992 to 1997 of major ions and other variables from an upland blanket bog in southwest England in ...
... We compare the effect of arbuscular mycorrhizal (AM) colonization and PO₄⁻³ fertilization on nitrate assimilation, plant growth and proline content in lettuce plants growing under well-watered (-0.04 MPa) or drought (-0.17 MPa) conditions. We also tested how AM-colonization and PO₄⁻³ fertilization influenced N uptake (¹⁵N) and the percentage of N derived from the fertilizer (% NdfF) by plants unde ...
... The potential for soils to produce nitrous oxide (N₂O) is impacted by past moisture conditions; however, the extent of this impact is not fully understood. We conducted the first review of this, using two literature searches and a meta‐analysis. We found 36 studies out of a possible 735 that described experiments where soil moisture conditions had been controlled, such that the impact of anteceden ...
Chernozems; air temperature; case studies; catalytic activity; colorimetry; cropland; detection limit; drought; enzyme kinetics; field experimentation; fluorescence; fluorometry; land use; monophenol monooxygenase; organic matter; oxidation; pastures; peroxidase; phenol
Abstract:
... The initial steps of complex organic matter degradation in soil comprise several oxidative processes catalysed by phenol oxidases and peroxidases. Commonly, their activity is determined by colorimetric approaches based on a range of substrates, making comparison between studies difficult. To improve this shortcoming, we conducted a calibration procedure for assessing phenol oxidase and peroxidase ...