Search results for "Runoff"

Soil and water losses from new citrus orchards growing on sloped soils in the western Mediterranean basin

2009

Ten representative research sites were selected in eastern Spain to assess soil erosion rates and processes in new citrus orchards on sloping soils. The experimental plots were located at representatives sites on limestone, in areas with 498 to 715 mm year−1 mean annual rainfall, north-facing slopes, herbicide treated, and new (less than 3 years old) plantations. Ten rainfall simulation experiments (1 h at 55 mm h−1 on 0·25 m2 plots) were carried out at each of the 10 selected study sites to determine the interill soil erosion and runoff rates. The 100 rainfall simulation tests (10 × 10 m) showed that ponding and runoff occurred in all the plots, and quickly: 121 and 195 s, respectively, fo…

Estimating soil loss of given return period by USLE-M-type models

2020

Many field investigations have clearly shown that rare and severe events control total soil erosion occurring over a long time period with up to 92% of total soil erosion over a 7‐year period resulting from just three daily events. Therefore, soil conservation strategies should be developed taking into account large events rather than long‐term average erosion. From an engineering point of view, establishing the soil loss of a given return period is needed. This can be obtained by the frequency analysis of soil loss measurements or by suitable soil erosion models. The USLE‐M modified and USLE‐M based are two empirical Universal Soil Loss Equation‐Modified (USLE‐M) type models which were dev…

A Comprehensive Check of Usle-Based Soil Loss Prediction Models at the Sparacia (South Italy) Site

2020

At first, in this paper a general definition of the event rainfall-runoff erosivity factor for the USLE-based models, REFe = (QR)b1(EI30)b2, in which QR is the event runoff coefficient, EI30 is the single-storm erosion index and b1 and b2 are coefficients, was introduced. The rainfall-runoff erosivity factors of the USLE (b1 = 0, b2 = 1), USLE-M (b1 = b2 = 1), USLE-MB (b1 ≠ 1, b2 = 1), USLE-MR (b1 = 1, b2 ≠ 1), USLE-MM (b1 = b2 ≠ 1) and USLE-M2 (b1 ≠ b2 ≠ 1) can be defined using REFe. Then, the different expressions of REFe were simultaneously tested against a dataset of normalized bare plot soil losses, AeN, collected at the Sparacia (south Italy) site. As expected, the poorest AeN predict…

Comparing Beerkan infiltration tests with rainfall simulation experiments for hydraulic characterization of a sandy-loam soil

2017

[EN] Saturated soil hydraulic conductivity, K-s, data collected by ponding infiltrometer methods and usual experimental procedures could be unusable for interpreting field hydrological processes and particularly rainfall infiltration. The K-s values determined by an infiltrometer experiment carried out by applying water at a relatively large distance from the soil surface could however be more appropriate to explain surface runoff generation phenomena during intense rainfall events. In this study, a link between rainfall simulation and ponding infiltrometer experiments was established for a sandy-loam soil. The height of water pouring for the infiltrometer run was chosen, establishing a sim…

Evidence de l'adaptation des communautés microbiennes sédimentaires de rivière à la minéralisation du diuron: influence du ruissellement et de l'éros…

2010

International audience; Purpose Surface runoff and erosion are major drivers of pesticide transport from soils to rivers draining vineyard watersheds. A recent study showed that applications of diuron on vineyards and diuron dispersal could lead to microbial adaptation to diuron biodegradation from treated soils to the receiving hydrosystem. Given the limited knowledge on microbial adaptation to pesticide degradation in aquatic environments, we conducted a microcosm study designed to assess the impact of runoff and erosion processes on the adaptation of riverine-sediment microbial communities to diuron mineralization. Materials and methods The experimental laboratory set-up consisted in aqu…

Finding Possible Weakness in the Runoff Simulation Experiments to Assess Rill Erosion Changes without Non-Intermittent Surveying Capabilities

2020

The Terrestrial Photogrammetry Scanner (TEPHOS) offers the possibility to precisely monitor linear erosion features using the Structure from Motion (SfM) technique. This is a static, multi-camera array and dynamically moves the digital videoframe camera designed to obtain 3-D models of rills before and after the runoff experiments. The main goals were to (1) obtain better insight into the rills

Long-term erosional responses after fire in the Central Spanish Pyrenees

2005

Abstract This paper reports the results of a study on how fire effects water and sediment losses in the Central Spanish Pyrenees where land abandonment results in an increase of the scrubland and fire-affected surfaces. In 1991, two plots (control and burnt) were installed to collect runoff, suspended sediments and solutes. One of the plots was burnt (burnt-1) and the other was covered by shrubs and herbs (control). During 1993, another burnt plot was installed (burnt-2). Data was collected from the three plots until 1999 and is used as the basis for assessing the soil erosion changes after the fire. Runoff, solute and suspended sediment concentration and erosion rates were slightly greater…

Un nuovo campionatore per la misura della perdita di suolo in parcelle attrezzate

2012

Le misure di perdita di suolo in parcelle attrezzate necessitano la conoscenza del peso del materiale eroso intercettato nella sezione terminale delle parcelle. Nell’area sperimentale di Sparacia attrezzata per la misura della perdita di suolo i deflussi torbidi prodotti in seguito ad un evento erosivo vengono convogliati mediante una grondaia posta a valle di ciascuna parcella all’interno di vasche di accumulo. Per misurare la frazione di materiale solido presente nel volume della sospensione raccolto in dette vasche, si propone l’utilizzo di un nuovo campionatore appositamente predisposto. Esso consiste in un cilindro di ottone, di noto diametro, dotato nella sezione terminale di una valv…

Delay times for saturation overland flow in forest soils

2007

Climate Change in the Mediterranean Basin (Part I): Induced Alterations on Climate Forcings and Hydrological Processes

2022

In the last years, the Mediterranean basin has been widely recognized as one of the most vulnerable areas in the world to climate change; because of its high concentration of urban and industrial settlements, it is one of the most impacted areas of the world in terms of water scarcity. The present paper aims at reviewing the main observed and predicted effects of climate change on hydrological processes directly related to water availability in the Mediterranean Basin, mainly focusing on the last ten years of research. While an in-depth discussion about possible future water scarcity problem in the Mediterranean area and the sources of uncertainty affecting future climate projections and im…