Fire effects on soil aggregation: A review

Abstract Fire can affect soil properties depending on a number of factors including fire severity and soil type. Aggregate stability (AS) refers to soil structure resilience in response to external mechanical forces. Many authors consider soil aggregation to be a parameter reflecting soil health, as it depends on chemical, physical and biological factors. The response of AS to forest fires is complex, since it depends on how fire has affected other related properties such as organic matter content, soil microbiology, water repellency and soil mineralogy. Opinions differ concerning the effect of fire on AS. Some authors have observed a decrease in AS in soils affected by intense wildfire or …

Editorial: The role of ash in fire-affected ecosystems

Organic carbon, water repellency and soil stability to slaking under different crops and managements: a case study at aggregate and intra-aggregate scales

This research studies the distribution of organic C and intensity of water repellency in soil aggregates with different size and in the interior of aggregates from Mediterranean soils under different crops (apricot, citrus and wheat) and management (con- 5 ventional tilling and no tilling/mulching). For this, undisturbed aggregates were sampled and carefully divided in size fractions (0.25–0.5, 0.5–1, 1–2, 2–5, 5–10 and 10–15 mm) or peeled to obtain separated aggregate layers (exterior, transitional and interior). Organic C content in the fine earth fraction of soils under different crops did not show important variations, although it increased significantly from conventionally tilled to 10…

Soil Mapping and Processes Models for Sustainable Land Management Applied to Modern Challenges

Abstract In the context of growing population and global change, increasing demands for food production are an enormous challenge that we face in the modern world. At the same time the need to prevent land degradation, restore lands that are already degraded, and maintain soil quality and health is critical to a sustainable use of land resources. Accurate maps and adequate models are indispensable tools to assist managers, scientists, and decision makers in addressing these challenges. In this chapter, we outline the main impacts of climate change on soils, key adaptation, and mitigation strategies and provide an overview of key issues in sustainable agricultural production as well as land …

Spatio-temporal Vegetation Recuperation after a Grassland Fire in Lithuania

The aim of this work is to study the spatio-temporal effects of a grassland fire in Lithuania. Immediately after the fire, a experimental plot was designed in a east-faced slope. Vegetation cover and height were measured 10, 17, 31 and 46 days after the fire (vegetation cover was only measured until 31 days after the fire because in the last measurement campaign the plot was completely covered). The results showed that vegetation recovered very fast. Ten days after the fire vegetation cover and height distribution were heterogeneous, decreasing with the time due to vegetation spread. Vegetation recovered was specially observed between 17 and 31 days after the fire due vegetation recuperatio…

Water repellency as conditioned by particle size and drying in hydrophobized sand

The effects of particle size and soil moisture on water repellency (WR) from hydrophobized sand are studied in this research. Quartz sand samples were separated into three sieve fractions: 0.5–2 mm (coarse sand, CS), 0.25–0.5 mm (medium sand, MS), and 0.05–0.25 mm (fine sand, FS). WR of sand was induced using different concentrations of stearic acid (SA; 0.5, 1, 5, 10, 20 and 30 g kg− 1). Moist samples have been exposed to two types of drying: air-drying at standard laboratory conditions and oven-drying at 50 °C. Change in moisture content, and water repellency has been monitored every 24 h for 10 days. After 1 day of drying, SA concentrations ≥ 10 g kg− 1 caused extreme WR in oven-dry samp…

The impact of road and railway embankments on runoff and soil erosion in eastern Spain

Abstract. Road and railway infrastructure increased in the Mediterranean region during the last three decades. This included the building of embankments, which are assumed to be a~large source of sediments and runoff. However, little is known about soil erosion rates, the factors that control them, and the processes that contribute to detachment, transport and deposition of sediments from road and railway embankments. The objective of this study was therefore to assess the impacts of road and railway embankments as a source of sediment and water, and compare them to other land use types (citrus plantations and shrublands) representative of the Cànyoles watershed to evaluate the importance o…

Do conservative agriculture practices increase soil water repellency? A case study in citrus-cropped soils

Water repellency is a property of soils that inhibits or delays infiltration. Long-term conservation practices as no-tillage, manure addition, application of herbicides may contribute to increase soil organic matter and, hence, soil water repellency. In this research, we have studied the effect of long-term addition of plant residues and organic manure, no-tillage and no chemical fertilization (MNT), annual addition of plant residues and no-tillage (NT), application of conventional herbicides and no-tillage (H), and conventional tillage (CT) on soil water repellency in Mediterranean calcareous citrus-cropped soils (Eastern Spain). Slight water repellency was observed in MNT soils, which may…

Modelling soil organic carbon stocks in global change scenarios: a CarboSOIL application

Abstract. Global climate change, as a consequence of the increasing levels of atmospheric CO2 concentration, may significantly affect both soil organic C storage and soil capacity for C sequestration. CarboSOIL is an empirical model based on regression techniques and developed as a geographical information system tool to predict soil organic carbon (SOC) contents at different depths. This model is a new component of the agro-ecological decision support system for land evaluation MicroLEIS, which assists decision-makers in facing specific agro-ecological problems, particularly in Mediterranean regions. In this study, the CarboSOIL model was used to study the effects of climate change on SOC …

Shrubland as a soil and water conservation agent in Mediterranean-type ecosystems

John Thornes found that shrubland was a key factor in the control of soil erosion on Mediterranean hillsides. His research inspired many scientists to investigate the impact of shrubland changes and management in semi-arid ecosystems. An example of Professor Thornes’ scientific influence is the experiment carried out on the El Teularet–Sierra de Enguera experimental station since 2003 which showed erosion rates on a 30-year-old abandoned orchard with dense vegetation cover of Ulex parviflorus and Cistus albidus and a 20-year-old fire-affected maquia with Quercus coccifera, Pistacia lentiscus and Juniperus oxycedrus. The measurements demonstrated that the shrubs help create more stable soil …

Effects of fire on ash thickness in a Lithuanian grassland and short-term spatio-temporal changes

Ash thickness is a key variable in the protection of soil against erosion agents after planned and unplanned fires. Thicker ash provides better protection against raindrop impact and reduces the runoff response by retaining water and promoting water infiltra5 tion although little is known about the distribution and the evolution of the ash layer after the fires. Ash thickness measurements were conducted along two transects (flat and sloping areas) following a a grid experimental design. Both transects extended from the burned area into an adjacent unburned area. We analysed ash thickness evolution according to time and fire severity. In order to interpolate data with accuracy and iden10 tif…

The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency-high magnitude simulated rainfall events

[EN] Soil and water losses due to agricultural mismanagement are high and non-sustainable in many orchards. An experiment was set up with rainfall simulation at 78 mm h(-1) over 1 hour on 20 paired plots of 2 m(2) (bare and straw covered) in new persimmon plantations in Eastern Spain. Effects of straw cover on the control of soil and water losses were assessed. An addition of 60% straw cover (75 gm(-2)) resulted in delayed ponding and runoff generation and consequently reduced water losses from 60% to 13% of total rainfall. The straw cover reduced raindrop impact and thus sediment detachment from 1014 to 47 g plot(-1) h(-1). The erosion rate was reduced from 5.1 to 0.2 Mg ha-(1) h(-1). The …

Role of rock fragment cover on runoff generation and sediment yield in tilled vineyards

The soil in conventional Mediterranean vineyards is an active and non-sustainable source of sediment and water. Lack of vegetation cover, small soil organic matter content and intense ploughing result in large rates of erosion in a millennia-old tillage system. There is a need for soil conservation strategies that enable sustainability of wine and grape production; therefore, it is essential to measure the rates and to investigate the processes and factors of soil erosion. This study evaluated factors that can reduce soil losses in traditional Mediterranean vineyards. The investigation was carried out with 96 rainfall simulation experiments at the pedon scale (0.24 m2) to measure soil detac…

Effects of soil management techniques on soil water erosion in apricot orchards.

Soil erosion is extreme in Mediterranean orchards due to management impact, high rainfall intensities, steep slopes and erodible parent material. Vall d'Albaida is a traditional fruit production area which, due to the Mediterranean climate and marly soils, produces sweet fruits. However, these highly productive soils are left bare under the prevailing land management and marly soils are vulnerable to soil water erosion when left bare. In this paper we study the impact of different agricultural land management strategies on soil properties (bulk density, soil organic matter, soil moisture), soil water erosion and runoff, by means of simulated rainfall experiments and soil analyses. Three rep…

Spatial Gradients of Intensity and Persistence of Soil Water Repellency Under Different Forest Types in Central Mexico

Organic residues release hydrophobic compounds to the soil that may induce soil water repellency (WR), which may inhibit infiltration and increase runoff and soil loss rates. Although there are many studies on soil WR through the world, very few investigations have been conducted in Mexican areas. This paper studies the natural background of soil WR in soils from central Mexico under representative forest types, analyzing the spatial distribution of soil WR in relation with tree canopy, vegetation cover and main soil chemical (pH, CaCO3, organic C content and exchangeable cations) and physical properties (texture). The water drop penetration time and the ethanol tests were used to assess pe…

Role of rock fragment cover on runoff generation and sediment yield in tilled vineyards

Summary The soil in conventional Mediterranean vineyards is an active and non-sustainable source of sediment and water. Lack of vegetation cover, small soil organic matter content and intense ploughing result in large rates of erosion in a millennia-old tillage system. There is a need for soil conservation strategies that enable sustainability of wine and grape production; therefore, it is essential to measure the rates and to investigate the processes and factors of soil erosion. This study evaluated factors that can reduce soil losses in traditional Mediterranean vineyards. The investigation was carried out with 96 rainfall simulation experiments at the pedon scale (0.24 m2) to measure so…

Corrigendum to “Do conservative agriculture practices increase soil water repellency? A case study in citrus-cropped soils” [Soil Tillage Res. 124 (2012), 233–239]

Runoff initiation, soil detachment and connectivity are enhanced as a consequence of vineyards plantations.

[EN] Rainfall-induced soil erosion is a major threat, especially in agricultural soils. In the Mediterranean belt, vineyards are affected by high soil loss rates, leading to land degradation. Plantation of new vines is carried out after deep ploughing, use of heavy machinery, wheel traffic, and trampling. Those works result in soil physical properties changes and contribute to enhanced runoff rates and increased soil erosion rates. The objective of this paper is to assess the impact of the plantation of vineyards on soil hydrological and erosional response under low frequency - high magnitude rainfall events, the ones that under the Mediterranean climatic conditions trigger extreme soil ero…

Splash erosion: A review with unanswered questions

66 Pags.- 1 Tabl.- 7 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/00128252

Assessment of soil suitability for improvement of soil factors and agricultural management

The dramatic growth of the world&rsquo

The immediate effectiveness of barley straw mulch in reducing soil erodibility and surface runoff generation in Mediterranean vineyards

Soil and water loss in agriculture is a major problem throughout the world, and especially in Mediterranean areas. Non-conservation agricultural practices have further aggravated the situation, especially in vineyards, which are affected by one of the highest rates of soil loss among cultivated lands. Therefore, it is necessary to find the right soil practices for more sustainable viticulture. In this regard, straw mulching has proven to be effective in other crop and fire affected soils, but, nonetheless, little research has been carried out in vineyards. This research tests the effect of barley straw mulching on soil erosion and surface runoff on vineyards in Eastern Spain where the soil …

Spatial models for monitoring the spatio-temporal evolution of ashes after fire-a case study of a burnt grassland in Lithuania

Ash thickness is a key variable in the protection of soil against erosion agents after planned and unplanned fires. Ash thickness measurements were conducted along two transects (flat and sloping areas) following a grided experimental design. In order to interpolate data with accuracy and identify the techniques with the least bias, several interpolation methods were tested in the grided plot. Overall, the fire had a low severity. However, the fire significantly reduced the ground cover, especially on sloping areas, owing to the higher fire severity and/or less biomass previous to the fire. Ash thickness depended on fire severity and was thin where fire severity was higher and thicker in lo…