Soil erosion controlled by biota along a climate gradient in Chile

2020 ◽  
Author(s):  
Nicolás Riveras ◽  
Kristina Witzgall ◽  
Victoria Rodríguez ◽  
Peter Kühn ◽  
Carsten W. Mueller ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Biological Soil Crust ◽  
Environmental Filtering ◽  
Soil Surface ◽  
Climatic Conditions ◽  
Rainfall Simulation ◽  
Soil Erodibility ◽  
Rainfall Gradient ◽  
The Impact ◽  
Semi Arid

<p>Soil erosion is one of the main problems in soil degradation nowadays and is widely distributed in many landscapes worldwide. Particularly water erosion is widespread and determined by rain erosivity, soil erodibility, topographic factors and the management carried out to mitigate this phenomenon. Although this process is mostly known as a consequence of human management such as agriculture or forestry, it is a process that also occurs naturally, being one of the factors that regulate the shape of the landscape.</p><p>One of the main agents that stabilize the soil surface is biota and its activity, either in the form of plants, microorganisms or as an assemblage in the form of a biological soil crust (biocrusts). However, there are limited studies about how and what extent biota drives soil-stabilizing processes. With particular view on the impact of biocrusts on soil erosion, most studies have been carried out in arid and semi-arid regions, so its influence under other climates is largely unknown.</p><p>This study focuses on the influence of biota on soil erosion in a temperature and rainfall gradient, covering four climate zones (arid, semi-arid, mediterranean and humid) with very limited human intervention. Other variables such as the origin of the geological formation, geographical longitude and glacial influence were kept constant for all study sites. The effect of vegetation (biocrusts) and its abundance, microbiology and terrain parameters are investigated using rainfall simulation experiments under controlled conditions and by a physico-chemical evaluation of the soil, surface runoff, percolation and sediment discharge, in order to determine the different environmental filtering effects that the soil develops under different climatic conditions.</p><p>It is expected that as vegetation vigor and cover increase, soil erodibility will decrease. The biocrust is the protagonist of this stabilization in conditions of low pedological development and will become secondary as edaphoclimatic conditions favor the colonization of plants.</p><p>The results of this study will help to achieve a better understanding of the role of biota in soil erosion control and will clarify its influence on soil losses under different climate and slope conditions. Analyses are currently ongoing and first results of our work will be presented at the EGU 2020.</p>

scholarly journals The impact of standard preparation practice on the runoff and soil erosion rates under laboratory conditions

Solid Earth ◽  
2016 ◽  
Vol 7 (5) ◽  
pp. 1293-1302 ◽  
Author(s):  
Abdulvahed Khaledi Darvishan ◽  
Vafa Homayounfar ◽  
Seyed Hamidreza Sadeghi
Keyword(s):  
Soil Erosion ◽  
Soil Loss ◽  
Soil Surface ◽  
Sediment Concentration ◽  
Rainfall Simulation ◽  
Natural Soil ◽  
Northern Iran ◽  
Soil Preparation ◽  
Loam Soil ◽  
The Impact

Abstract. The use of laboratory methods in soil erosion studies, rainfall simulation experiments, Gerlach troughs, and other measurements such as ring infiltrometer has been recently considered more and more because of many advantages in controlling rainfall properties and high accuracy of sampling and measurements. However, different stages of soil removal, transfer, preparation and placement in laboratory plots cause significant changes in soil structure and, subsequently, the results of runoff, sediment concentration and soil loss. Knowing the rate of changes in sediment concentration and soil loss variables with respect to the soil preparation for laboratory studies is therefore inevitable to generalize the laboratory results to field conditions. However, there has been little attention given to evaluate the effects of soil preparation on sediment variables. The present study was therefore conducted to compare sediment concentration and soil loss in natural and prepared soil. To achieve the study purposes, 18 field 1 ×  1 m plots were adopted in an 18 % gradient slope with sandy–clay–loam soil in the Kojour watershed, northern Iran. A portable rainfall simulator was then used to simulate rainfall events using one or two nozzles of BEX: 3/8 S24W for various rainfall intensities with a constant height of 3 m above the soil surface. Three rainfall intensities of 40, 60 and 80 mm h−1 were simulated on both prepared and natural soil treatments with three replications. The sediment concentration and soil loss at five 3 min intervals after time to runoff were then measured. The results showed the significant increasing effects of soil preparation (p ≤ 0.01) on the average sediment concentration and soil loss. The increasing rates of runoff coefficient, sediment concentration and soil loss due to the study soil preparation method for laboratory soil erosion plots were 179, 183 and 1050 % (2.79, 2.83 and 11.50 times), respectively.

Regulation and Critical Threshold of Grass Cover on Slope Runoff in LoessHilly Gully Region under Artificial

2021 ◽  
Author(s):  
Qiufen Zhang ◽  
Xizhi Lv ◽  
Rongxin Chen ◽  
Yongxin Ni ◽  
Li Ma
Keyword(s):  
Soil Erosion ◽  
Rainfall Intensity ◽  
Climatic Conditions ◽  
Vegetation Coverage ◽  
Critical Threshold ◽  
Runoff Generation ◽  
Grassland Vegetation ◽  
Slope Flow ◽  
The Impact ◽  
Slope Runoff

<p>The slope runoff caused by rainstorm is the main cause of serious soil and water loss in the loess hilly area, the grassland vegetation has a good inhibitory effect on the slope runoff, it is of great significance to reveal the role of grassland vegetation in the process of runoff generation and control mechanism for controlling soil erosion in this area. In this study, typical grassland slopes in hilly and gully regions of the loess plateau were taken as research objects. Through artificial rainfall in the field, the response rules of slope rainfall-runoff process to different grass coverage were explored. The results show that: (1) The time for the slope flow to stabilize is prolonged with the increase of vegetation coverage, and shortened with the increase of rainfall intensity; (2) At 60 mm·h <sup>−1</sup> rainfall intensity, the threshold of grassland vegetation coverage is 75.38%; at 90 mm·h<sup> −1</sup> rainfall intensity, the threshold of grassland vegetation coverage is 90.54%; at 120 mm·h <sup>−1</sup> rainfall intensity, the impact of grassland vegetation coverage on runoff is not significant; (3) the Reynolds number and Froude number of slope flow are 40.07‒695.22 and 0.33‒1.56 respectively, the drag coefficient is 1.42‒43.53. Under conditions of heavy rainfall, the ability of grassland to regulate slope runoff is limited. If only turf protection is considered, about 90% of grassland coverage can effectively cope with soil erosion caused by climatic conditions in loess hilly and gully regions. Therefore, in loess hilly areas where heavy rains frequently occur, grassland's protective effect on soil erosion is obviously insufficient, and investment in vegetation measures for trees and shrubs should be strengthened.</p>

scholarly journals Impact of skidder and high-lead system logging on forest soils and advanced regeneration

2012 ◽  
Vol 49 (No. 6) ◽  
pp. 273-280 ◽  
Author(s):  
M. Modrý ◽  
D. Hubený
Keyword(s):  
Czech Republic ◽  
Forest Ecosystem ◽  
Natural Regeneration ◽  
Soil Surface ◽  
Beech Forest ◽  
Climatic Conditions ◽  
Lead System ◽  
The Impact ◽  
High Lead ◽  
Stand Conditions

The applied skidding technology strongly influences the impact of harvest on the ecosystem and success of natural regeneration. The impact of skidder SLKT 81 and high-lead system Larix 3T on forest soil and natural regeneration was compared under analogical site and stand conditions in a production beech forest in the environs of Brno, Czech Republic. The skidder was found to have greater effects on the soil surface consistency, soil properties and natural regeneration than the high-lead system operations. Although high-lead system operations are more friendly to all parts of forest ecosystem, the skidder may not cause excessive damage when applied under suitable terrain and climatic conditions.

scholarly journals The Effect of Shallow Tillage on Soil Erosion in a Semi-Arid Vineyard

Agronomy ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 257 ◽  
Author(s):  
Agata Novara ◽  
Giovanni Stallone ◽  
Artemio Cerdà ◽  
Luciano Gristina
Keyword(s):  
Soil Erosion ◽  
Soil Degradation ◽  
Erosion Rate ◽  
Arable Land ◽  
Water Erosion ◽  
Soil Tillage ◽  
Strip Tillage ◽  
The Impact ◽  
Semi Arid ◽  
Tillage Erosion

Soil erosion has been considered a threat for semi-arid lands due to the removal of solid materials by water and wind. Although water erosion is currently considered the most important process of soil degradation, a growing interest has been drawn to the impact of soil tillage. Although numerous studies on tillage erosion have been carried out on arable land using a moldboard plow, a chisel, and a tandem disc for different crops, there are no studies on the effect of shallow tillage on soil redistribution in vineyards. The aim of this work was to evaluate the soil tillage erosion rate in a vineyard using a 13C natural abundance tracer. A strip of soil (C3-C soil) was removed, mixed with C4-C tracer, and replaced. After the installation of the strip, tillage (upslope in one inter-row and downslope in the other inter-row) was performed with a cultivator and soil was collected along the slope with an interval of 0.2 m from the C4-C strip. Soil organic carbon and δ13C were measured and the total mass of translocated soil (T) soil was calculated. The net effect of tillage after two consecutive operations (downslope and upslope tillage) was a T of 49.3 ± 4.2 kg m−1. The estimated annual erosion rate due to tillage in the studied vineyard was 9.5 ± 1.2 Mg ha−1year−1. The contribution of the soil tillage erosion rate was compared with that of water erosion in the same vineyard, and we conclude that tillage is a threat to soil degradation.

Sediment content and chemical properties of water runoff on biocrusts in drylands

Biologia ◽  
2014 ◽  
Vol 69 (11) ◽  
Author(s):  
Roberto Lázaro ◽  
Juan Mora
Keyword(s):  
Dry Matter ◽  
Chemical Properties ◽  
Soil Surface ◽  
Water Erosion ◽  
Rainfall Simulation ◽  
Water Runoff ◽  
Protective Capacity ◽  
Runoff Water ◽  
Wide Range ◽  
The Impact

AbstractIn drylands, water erosion can be a process with important economic and ecological implications, and is very dependent on the soil surface cover. There is broad agreement that biocrusts protect the soil from erosion in a wide range of circumstances. However, there is little information available on the effect of rain and biocrust types on this protective capacity and there is particularly very little knowledge on the erosive effects of runoff on biocrusts, which are expected to be larger in larger drainage areas, on the resistance of biocrusts to the combined effect of raindrops plus runoff flow and on the solute mobilisation by runoff in biocrusts. To answer these questions, we performed 96 rainfall-simulation in situ factorial experiments, including two biocrust types (cyanobacteria and lichens), three rain types (42, 63 and 77 mm h−1, always 20 min rain), four plot lengths (1, 2, 3 and 4 m long) and four replicates. In each experiment, runoff volume was measured and a runoff sample was taken to determine (i) the amount of dry matter in runoff, (ii) the amount of organic matter among the dry matter, (iii) the electrical conductivity, pH and alkalinity in runoff water. The main findings were: biocrusts strongly protected soil against water erosion, even under the most erosive conditions, and the protection increased with the successional development. Biocrusts were very resistant to the impact of raindrops and also to runoff flow, although an emergent hypothesis arose: under the most erosive conditions, a threshold of erodibility could be reached at the cyanobacterial biocrust. The lichen crust also protected the soil against the removal of soil soluble substances. The development of a biocrust could change the chemical composition of the solutes in runoff.

scholarly journals Crop Residues Management under Changing Climate Scenario

2021 ◽  
pp. 21-28
Author(s):  
May Zar Myint ◽  
Raihana Habib Kanth ◽  
F. A. Bahar ◽  
S. S. Mehdi ◽  
A. A. Saad ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Sustainable Agriculture ◽  
Natural Resources ◽  
Agricultural Sector ◽  
Crop Residues ◽  
Soil Surface ◽  
Residue Management ◽  
Limiting Factor ◽  
Natural Ecosystem ◽  
The Impact

Soil is the fundamental and necessary natural resource for the agricultural production system. Due to the increasing global population and the impact of climate changes, natural resources are the major limiting factor to use widely for food production. The major factors responsible for the deterioration of natural resources are extreme events caused by man-made activities and unexpected and unpredictable adverse natural forces of nature. Among the different degradation processes, soil erosion is one of the serious threatens to the deterioration of soil for the agricultural sector and healthy ecosystem conservation. Intensive agricultural practices are particularly caused by the acceleration of the soil erosion process. Therefore, the good and systematic management of soil resources is indispensable not only for sustainable agriculture or conservation agriculture but also for the protection and reduction of the natural ecosystem. Covering crop residues on soil enhances organic matter, protects the soil surfaces, maintains water and nutrients, improves soil biological activity and chemical composition, and contributes to pest management. Therefore, crop residue management is one of the conservation practices and is designed to leave sufficient residue on the soil surface to reduce wind and water erosion. It includes all field operations that affect the amount of residue, its an orientation to the soil surface and prevailing wind and rainfall patterns and the residue distribution throughout the period requiring protection. This paper especially highlights the status of soil erosion, crop residues, and management in crop residues in sustainable agriculture.

scholarly journals ASSESSMENT OF SOIL EROSION BY SIMULATING RAINFALL ON AN EQUATORIAL ORGANIC SOIL

2017 ◽  
Vol 8 (2) ◽  
pp. 72-81
Author(s):  
Johari A.H ◽  
Law P.L. ◽  
Taib S.N.L. ◽  
Yong L.K.
Keyword(s):  
Soil Erosion ◽  
Soil Loss ◽  
Organic Soil ◽  
Coarse Sand ◽  
Soil Samples ◽  
Soil Erodibility ◽  
Simulated Rainfall ◽  
Construction Sites ◽  
The Impact ◽  
Soil Loss Equation

Soil erosion occurs on construction sites partly due to site clearing that exposes the land to the erosive power of rainfall. A proposed construction project requires the submission of an Environmental Impact Assessment EIA) to assess the impact of the project on the environment. Assessment of soil erosion is included in the EIA, but the equation to estimate soil erosion known as the Universal Soil Loss Equation (USLE) is only applicable to a soil containing up to four percent organic matter. This limitation of USLE requires an alternative that can predict soil erosion on an organic soil. This study attempts to assess erosion that occurs on an organic soil by simulated rainfall. Field soil samples were reconstructed into three shapes and exposed to simulated rainfall. Results indicate that the amount of organic soil loss decreases with increasing duration of rainfall. Particle size distribution shows that particles with sizes finer than coarse sand (1.7 mm) remained on the slopes. Equations were developed from the graphs of soil loss versus duration of simulated rainfall to estimate soil loss occurring on slopes covered by an organic soil. The outcome of this study can be a precursor to developing an equation to estimate soil erodibility of a slope overlain by an organic soil.

scholarly journals Estimating a mathematical formula of soil erosion under the effect of rainfall simulation by digital close range photogrammetry technique

2021 ◽  
Author(s):  
Hossam El-Din Fawzy ◽  
◽  
Ali Basha ◽  
Marco N. Botross ◽  
◽  
...  
Keyword(s):  
Soil Erosion ◽  
Sandy Soil ◽  
Soil Surface ◽  
Rainfall Simulation ◽  
Surface Model ◽  
Surface Erosion ◽  
Hybrid Technique ◽  
Mathematical Formula ◽  
Close Range Photogrammetry ◽  
Close Range

A new design of soil erosion and rainfall simulator is presented at this study as an attempt to deduce a mathematical formula of soil surface erosion phenomenon to describe the behavior of the sandy soil under the rainfall simulation, soil deformation such as the gullies and surface eroding rills are monitored by the Digital Close Range Photogrammetry (DCRP) technique that includes capturing digital images by a smart cellphone camera, and a Terrestrial Laser Scanner (TLS) to digitalize the soil surface as a point cloud data to produce Digital Elevation Models (DEM) with an accuracy reaches 0.10mm with the watershed, color relief, 3D surface model. The results show that the mentioned methods give a typical digital surface feature express especially of using geometrical adjustment that controls the orientation of the digital surface. The SIFT technology of the digital imaging feature detection achieves accurate results despite its small cost, 12% if compared to the TLS method. As a result of the statistical observations, a simple mathematical formula was generated through the DCRP technique that describes the sandy soil behavior under a hybrid technique of rainfall simulation as a relation between the eroding rate and the duration through the different gradient slopes.

On the effect of different moss species on soil erosion, percolation and carbon relocation

2021 ◽  
Author(s):  
Corinna Gall ◽  
Lena Grabherr ◽  
Martin Nebel ◽  
Thomas Scholten ◽  
Sonja M. Thielen ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Surface Runoff ◽  
Biological Soil Crust ◽  
Bare Soil ◽  
Individual Species ◽  
Sediment Discharge ◽  
Moss Species ◽  
Moss Cover ◽  
The Impact ◽  
Soil Substrates

<p>For decades, soil erosion has been a major environmental problem as it degrades the most productive soil layers, which threatens, among other things, food production worldwide. Although these effects have been known for a long time, there are still a variety of challenges to mitigating soil erosion in different ecosystems. As climate change progresses, the risk of soil loss increases, making the preparation of effective solutions very urgent. A current research focus is on the restoration of a protective soil cover following disturbances in the vegetation layer, e.g., through the reestablishment of biological soil crust communities. These are often dominated by bryophytes in humid climates. So far, several studies examined the general protective influence of bryophytes against soil erosion, however only few of them addressed how individual species affect specific erosion processes in detail.</p><p>To fill this research gap we investigated the impact of six moss species on soil erosion, percolation and carbon relocation by means of rainfall simulations. Therefore, we used topsoil substrate from four sites in the Schönbuch Nature Park in South Germany which covers different kinds of bedrock and varying soil texture and pH. Subsequently, they were sieved by 6.3 mm and filled into metal infiltration boxes (40 x 30 cm) up to a height of 6.5 cm. The moss species differ in origin (either collected in the field or cultivated in the lab) as well as growth form (pleurocarpous or acrocarpous). Rainfall simulations were performed for bare soil substrates, as well as for moss-covered soil substrates six months later and both in dry and wet conditions. Additionally, we conducted rainfall simulations with leaf and coniferous litter on bare soil substrates. During the simulations we monitored soil moisture in two position - 3 cm depth plus soil surface - with biocrust wetness probes (BWP) and quantified surface runoff, percolation and sediment discharge. Afterwards we determined carbon contents of the sediment and dissolved organic carbon in the liquid phase of runoff and percolated water.</p><p>While surface runoff was increased by 5% due to the litter cover compared to the bare soil substrate, sediment discharge decreased to 97%. Runoff rates could also be mitigated by 90 % as a result of the moss cover. Furthermore, due to the dense moss cover sediment rates were almost reduced to zero. Preliminary results show that there are differences between the moss species in terms of sediment discharge, but not in context with runoff. The analyses of carbon contents in surface runoff and the percolated water are still in progress, as is the evaluation of the BWP measurements. These outcomes will be presented at vEGU21.</p>

scholarly journals Impact assessment of climate change on hydro-climatic conditions of arid and semi-arid watersheds (case study: Zoshk-Abardeh watershed, Iran)

2020 ◽  
Author(s):  
Mohadese Rahimpour ◽  
Mohamad Tajbakhsh ◽  
Hadi Memarian ◽  
Amirhosein Aghakhani Afshar
Keyword(s):  
Climate Change ◽  
Assessment Tool ◽  
Climatic Conditions ◽  
Future Period ◽  
Eastern Iran ◽  
Temperature Component ◽  
The Impact ◽  
Semi Arid ◽  
Far Future

Abstract The hydrologic cycle in the river basins of semi-arid regions is severely influenced by climate change. The aim of this study is to assess the impact of climate change on the hydro-climatic condition in Zoshk-Abardeh watershed in eastern Iran. The Soil and Water Assessment Tool (SWAT) was calibrated using the Sequential Uncertainty Fitting – Version 2 (SUFI-2) algorithm to improve the simulation results of the runoff. The Model for Interdisciplinary Research on Climate-Earth System Models (MIROC-ESM) was used to investigate the effects of climate change on hydro-climatic components under the representative concentration pathway scenarios (RCPs: 2.6, 4.5, 6.0, and 8.5) and in near- (2014–2042), mid- (2042–2071), and far- (2072–2100) futures. The temperature component under the RCP4.5 and RCP6.0 during the near- and mid-future intervals and the far-future period (for RCP6.0) indicated a significant rising trend. The rainfall parameter in all RCPs and future intervals showed an insignificant descending trend. Runoff alterations under the RCP4.5 amid the mid- to far-future intervals and under the RCP8.5 throughout the far-future period trailed a significant descending trend. The results determined that the temperature will track an upward tendency, while precipitation and runoff will follow a descending trend in this watershed by the end of the 21st century.

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