Search results for "soil pH"
showing 10 items of 129 documents
Soil macrofauna and organic matter in irrigated orchards under Mediterranean climate
2017
Soil fauna abundance and diversity and organic matter content are key indicators for the rate of soil degradation in Mediterranean-type ecosystems. The soil macrofauna populations were examined in three orange (Citrus sinensis) orchards and one persimmon (Diospyros kaki) orchard, with the same soil type and different management systems, to establish whether organic management benefits soil fauna and soil quality and what is the effect of flood irrigation. Vegetation cover, soil organic matter, bulk density and moisture were measured at each experimental site within the Canyoles watershed in Eastern Spain in summer of 2015. Earthworm abundance was highest at the organic orchard with flood ir…
Soil quality indicators as affected by a long term barley-maize and maize cropping systems
2011
Most soil studies aim a better characterization of the system through indicators. In the present study nematofauna and soil structure were chosen as indicators to be assess soil health as related to agricultural practices. The field research was carried out on the two fodder cropping systems continuous maize (CM, Zea mays L.) and a 3-year rotation of silage-maize – silage-barley (Hordeum vulgare L.) with Italian ryegrass (R3) and grain-maize maintained in these conditions for 18 years. Each crop system was submitted to two management options: 1) the high input level (H), done as a conventional tillage, 2) the low input level (L), where the tillage was replaced by harrowing and the…
BIOCHARS IN SOILS: TOWARDS THE REQUIRED LEVEL OF SCIENTIFIC UNDERSTANDING
2017
The special issue on Biochar as an Option for Sustainable Resource Management Key priorities in biochar research for future guidance of sustainable policy development have been identified by expert assessment within the COST Action TD1107. The current level of scientific understanding (LOSU) regarding the consequences of biochar application to soil were explored. Five broad thematic areas of biochar research were addressed: soil biodiversity and ecotoxicology, soil organic matter and greenhouse gas (GHG) emissions, soil physical properties, nutrient cycles and crop production, and soil remediation. The highest future research priorities regarding biochar’s effects in soils were: functional …
Effects of pentachlorophenol in forest soil: a microcosm experiment for testing ecosystem responses to anthropogenic stress
1996
Changes in the structure and function of a soil decomposer community and growth of birch (Betula pendula) due to chemical contamination were studied in laboratory microcosms. Sodium pentachlorophenate (PCP) was added to the humus layer of a simulated forest soil at three nominal concentrations (0, 50 and 500 mg kg-1 dry mass). After two growing periods (48 weeks), there were more small soft-bodied mites, but less collembolans and microbial biomass, in the higher PCP concentration treatment than in the other treatments. Number of enchytraeids were significantly reduced and fungal-feeding nematodes became extinct in the soil with the higher PCP concentration. Soil respiration did not change d…
Long-term effects of soil management on ecosystem services and soil loss estimation in olive grove top soils
2016
Soil management has important effects on soil properties, runoff, soil losses and soil quality. Traditional olive grove (OG) management is based on reduced tree density, canopy size shaped by pruning and weed control by ploughing. In addition, over the last several decades, herbicide use has been introduced into conventional OG management. These management strategies cause the soil surface to be almost bare and subsequently high erosion rates take place. To avoid these high erosion rates several soil management strategies can be applied. In this study, three strategies were assessed in OG with conventional tillage in three plots of 1. ha each. Soil properties were measured and soil erosion …
Nitrogen losses in vineyards under different types of soil groundcover. A field runoff simulator approach in central Spain
2017
The soils of Mediterranean vineyards are usually managed with continuous tillage, resulting in bare soil, low infiltration and high soil erosion rates. Soil nutrients, such as nitrogen, could be lost dissolved in the runoff, causing a decrease in soil fertility on such degraded soils and producing eutrophication downstream. The influences of groundcover on the soil erosion processes and sediment yields in Mediterranean vineyards have been widely addressed. However, the runoff process itself, excluding the effect of raindrop impacts, has barely been studied. Thus, a field runoff simulator was built to assess runoff and nutrient losses under different soil management strategies in Central Spa…
The effect of alternating different water qualities on accumulation and leaching of solutes in a Mediterranean cracking soil
2002
The relevance of bypass flow on water flow, solute or pesticide transport is becoming increasingly recognized. Recent investigations proved that soil salinization may be influenced by bypass flow, i.e. the rapid transport of water and solutes via macropores and/or shrinkage cracks to subsoil and groundwater. This paper explores the role of bypass flow in the process of accumulation and leaching of solutes, as well as of sodium, in a Mediterranean cracking soil irrigated with saline/sodic waters. The results of bypass flow experiments performed on undisturbed soil cores showed that leaching of solutes occurred in concomitance with bypass fluxes when a low salinity solution was alternated wit…
Laboratory testing of Beerkan infiltration experiments for assessing the role of soil sealing on water infiltration
2018
Abstract Soil surface sealing is a major cause of decreased infiltration rates and increased surface runoff and erosion during a rainstorm. The objective of this paper is to quantify the effect of surface sealing on infiltration for 3 layered soils with different textures for the upper layer and investigate the capability of BEST procedure to catch the formation of the seal and related consequences on water infiltration. Rainfall experiments were carried out to induce the formation of the seal. Meanwhile, Beerkan infiltration runs were carried out pouring water at different distances from the soil surface (BEST-H versus BEST-L runs, with a High and Low water pouring heights, respectively) f…
The influence of pulsed redox conditions on soil phosphorus
2010
Abstract. The effects of eleven pulsed reduction-oxidation cycles (20 and 2 days, respectively) on soil phosphorus (P) dynamics are compared for 12 soils having contrasting properties and overfertilised with respect to P. Incubation conditions simulated transient waterlogging of the soil profile and involved repeated sampling and analysis of both the solution and solid phase P forms. An initial increase in P concentration occurred upto and including the fourth full cycle was followed by a sharp decline in concentration for all but one soil. Accompanying changes in the main extractable forms of P, which appeared to be cumulative, could be summarised as a general decline in the organic P frac…
Dependence of accelerated degradation of atrazine on soil pH in French and Canadian soils
2000
Abstract A series of agricultural soils varying in their atrazine treatment history were sampled from 12 sites in France and two sites in Canada. The soils varied widely with respect to soil chemical, physical and microbiological (total microbial biomass, kinetics of C and N mineralization) properties. Soils treated with as few as two successive atrazine field applications mineralized [U- ring - 14 C]atrazine significantly more rapidly in 35 d laboratory incubations than did soils which had never received atrazine. Longer treatment history tended to favour more rapid mineralization in the so-called “adapted” soils. Up to 80% of the initially applied 14 C-atrazine was mineralized at the end …