Search results for "forestry"
showing 10 items of 1998 documents
SW—Soil and Water
2000
Abstract Recent research has directed attention to the properties of the eroded material because of its influence in deposition phenomena and in carrying capacity of pollutant materials. In this paper, the spatial distribution of the content of nitrogen, phosphorus and total organic carbon is firstly deduced using the measurements carried out in 129 soil samples well distributed over the Sicilian Sparacia Basin and a Kriging interpolation method. Then the load of each chemical was calculated at morphological unit and basin scale using the above-mentioned spatial distributions and sediment yield values calculated by a parametric approach such as the revised universal soil loss equation (RUSL…
Evaluation of disruption of sediment connectivity and herbicide transport across a slope by grass strips using a magnetic iron oxide tracer
2018
Abstract The use of cover crops has been prescribed as a mitigation measure for offsite contamination, as they reduce sediment and agrochemical loads, thus reducing the hydrological connectivity of the land. However, there is the need to quantify its effectiveness for specific agrochemicals in broader range of conditions, to validate management for its safe environmental use. The objectives of the present study were: (1) to explore the use of simulated rainfall and magnetic iron oxide to understand the impact of vegetation strips on runoff and soil losses at the plot scale and, (2) to evaluate the effectiveness of vegetation strips in buffering sediment and herbicides coming from bare soil …
Stemflow determination in forest stands
1997
Abstract A stemflow measurement technique is described, based on: (1) correlations between stemflow volume and tree diameters at breast height (DBH), determined on the basis of a relatively low number of tree samplings; (2) the distribution of trees in the stand relative to their DBH. Stemflow for trees in a stand (mm) can thus be determined from total rainfall (mm). The results were compared to those obtained with two other stemflow determination techniques. The proposed method was found to be more reliable, precise and easier to apply than the standard methods.
The role of vegetation on gully erosion stabilization at a severely degraded landscape: A case study from Calhoun Experimental Critical Zone Observat…
2018
Abstract Gully erosion was evidence of land degradation in the southern Piedmont, site of the Calhoun Critical Zone Observatory (CCZO), during the cotton farming era. Understanding of the underlying gully erosion processes is essential to develop gully erosion models that could be useful in assessing the effectiveness of remedial and soil erosion control measures such as gully backfilling, revegetation, and terracing. Development and validation of process-based gully erosion models is difficult because observations of the formation and progression of gullies are limited. In this study, analytic formulations of the two dominant gullying processes, namely, plunge pool erosion and slab failure…
KAJIAN PENANGGULANGAN KERUSAKAN LAHAN AKIBAT PERUBAHAN PENGGUNAAN LAHAN DENGAN PENDEKATAN MODEL HIDROLOGI PADA DAS PAMI
2018
<em>Changes in land use in watershed will affect peak discharge and degradation land. It is becoming an indicator of better or worse use of land in watershed area. This study aims to analysis land use change, to predict peak flows based on changes in land use and land use change scenarios in the Pami watershed. This study uses a number of primary data and secondary data. Primary data were obtained from observations of the condition of the land and soil sampling, which is then analyzed in the laboratory. Secondary data were obtained from literature and related agencies such as geographical map and thematic maps including land map, administrative area maps, land use maps in 1996-2015 an…
Analyzing long-term soil erosion in a ridge-shaped persimmon plantation in eastern Spain by means of ISUM measurements
2019
Abstract Graft unions of cultivated plants have been used as passive bio-indicators to assess long-term soil erosion rates. By taking complementary topographical measures in inter-row areas, soil erosion can be more accurately estimated as done with the Improved Stock Unearthing Method (ISUM) in vineyards. As vines are not the only plants that are grafted, ISUM could be also applied to other crops. Most fruit trees are planted in ridges and our objective was to test if ISUM could be applied in a ridge planted persimmon plantation. This update in the methodology will allow the scientific community to expand measurements that will contribute to assessing soil erosion processes in intensive an…
Post-fire hydrological response and suspended sediment transport of a terraced Mediterranean catchment
2017
In July 2013, a wildfire severely affected the western part of the island of Mallorca (Spain). During the first three post-fire hydrological years, when the window of disturbance tends to be more open, the hydrological and sediment delivery processes and dynamics were assessed in a representative catchment intensively shaped by terracing that covered 37% of its surface area. A nested approach was applied with two gauging stations (covering 1.2 km2 and 4.8 km2) built in September 2013 that took continuous measurements of rainfall, water and sediment yield. Average Suspended Sediment Concentration (1,503 mg l-1) and the maximum peak (33,618 mg l-1) were two orders of magnitude higher than tho…
Spatial patterns of sediment connectivity in terraced lands: Anthropogenic controls of catchment sensitivity
2017
In recent decades the dynamics of global change in developed countries has led to significant alterations in the hydrological and sediment dynamics of terraced land. Agricultural terraces were built to control overland flow and prevent erosion, acting as buffers and barriers throughout the sediment cascading system. Their abandonment and degradation increase the sensitivity of the catchment, promoting the collapse of dry-stone walls and the reworking of stored sediment. In this study, a geomorphometric Index of Connectivity (IC) –derived from high-resolution LiDAR data (0.9 pt m-2, RMSE Q8). This spatial matching was related to feedback dynamics between structural and functional connectivit…
Distribution of soil organic carbon in Wadi Al-Thulaima, Saudi Arabia: A hyper-arid habitat altered by wastewater reuse
2018
The carbon cycle is being altered as a result of human-induced changes in the Earth's system. Therefore, ecosystems such as wetlands, authentic CO2 sinks, are becoming especially important. Little information exits on the soil organic carbon (SOC) stock for the middle east-countries man-made wetlands making wadis permanent with the outflow of wastewater treatment plants. This paper presents the vertical distribution of SOC content, soil bulk density (SBD) and SOC density in soil of vegetated and bare sites in Wadi Al-Thulaima, one of the artificial wetlands in central Saudi Arabia. The mean distribution of SBD in the vegetated and bare sites increased significantly with depth. Inversely, th…
Exploring calibration strategies of the SEDD model in two olive orchard catchments
2017
To optimize soil conservation strategies in catchments, it is required an accurate diagnosis of the areas contributing to soil erosion by using models such as SEDD (Sediment Delivery Distributed model). In this study, different calibration strategies of the SEDD model were explored to adapt its use in two olive catchments with different environmental features and managements. A data series of rainfall–runoff–sediment load, collected in the catchments for 6 years was used: i) to evaluate calibration strategies for different management and flow conditions through the analysis of the C and R factors, and ii) to describe the temporal patterns of sediment delivery ratio (SDR) at the event and an…