Search results for "hydrology"

Single-channel and two-channel methods for land surface temperature retrieval from DAIS data and its application to the Barrax site

2004

In this paper, a methodology using a single-channel and a two-channel method is presented to estimate the land surface temperature from the DAIS (Digital Airborne Imaging Spectrometer) thermal channels 74 (8.747 µm), 75 (9.648 µm), 76 (10.482 µm), 77 (11.266 µm), 78 (11.997 µm) and 79 (12.668 µm). The land surface temperature retrieved with both methods has been validated over the Barrax site (Albacete, Spain) in the framework of the DAISEX (Digital Airborne Imaging Spectrometer Experiment) field campaigns. Prior to the validation an analysis of the DAIS data quality has been performed in order to check the agreement between in situ data and the values extracted from the DAIS images supplie…

Soil erosion after land abandonment in a semiarid environment of southeastern Spain

1997

Different soil units were selected in southeastern Spain to investigate the effects of land abandonment on soil erosion under semiarid conditions. The study sites selected were a cultivated field (bare), a 3‐yr‐abandoned field (herbs), a 10‐yr‐abandoned field (Artemisia herba‐alba Asso.), and two soil units covered with semi‐native (Stipa tena‐cissima L) and native (Pinus halepensis Miller) vegetation. Simulated rainfall measurements showed that the erosion and runoff increased after the land abandonment, but later erosion decreased owing to the influence of increasing vegetation. Runoff discharge (35%) and the erosion rates (334 g m2 h‐1) were high in the 3‐yr‐abandoned land in comparison …

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

2013

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 …

Properties and erosional response of soils in a degraded ecosystem in Crete (Greece)

2013

To study desertification processes relating to soil erosion, a climatological and altitudinal gradient from south to north was selected in Crete (Greece) and four locations were selected along the gradient. At the locations precipitation ranged from 1400 mm/year at the highest location to 400 mm/year at the lowest. All locations are affected by the actual land use: intensive grazing, small controlled fires, and abandoned agricultural terraces. Representative soil profiles were described in the field and analyzed in the laboratory, and rainfall simulation experiments in the field measured soil erosion over different soil surfaces and land uses. Data on physical and chemical properties were o…

Detecting crop water status in mature olive orchards using vegetation spectral measurements.

2014

Full spectral measurements (350–2500 nm) at tree canopy and leaf levels and the corresponding leaf water potentials (LWP) were acquired in an olive grove of Sicily, at different hours of the day, during summer season 2011. The main objective of the work was to assess, on the basis of the experimental data-set, two different approaches to detect crop water status in terms of LWP. Specifically, using existing families of Vegetation Indices (VIs) and applying Partial Least Squares Regression (PLSR) were optimised and tested. The results indicated that a satisfactory estimation of LWP at tree canopy and leaf levels can be obtained using vegetation indices based on the near infrared–shortwave in…

Sampling of Residential Water Use for Leak Control via Water Budgets

2009

Application of Magnetic Susceptibility Measurements for Identification of Technogenic Horizons in Soil Profiles on the Example of the Vistula River C…

2017

Studies on magnetic properties of soils have been recently applied in the soil environment quality monitoring in relation to basic physical and chemical properties. However, the issue of distribution of ferrimagnetic materials in particular genetic soil horizons, especially in altered soils, has not yet been considered in environmental studies. The main subject of the research was to evaluate a potential of magnetic susceptibility measurements as implements for supporting the soil classification through indication of particular distinctive genetic horizons in the soil profile. The study objects were soils whose formation was strictly conditioned by hydrotechnical regulations in the area of …

Using Static and Dynamic Indicators to Evaluate Soil Physical Quality in a Sicilian Area

2013

Both capacitive indicators derived from the water retention curve and dynamic measurements of the flow-weighted mean pore radius, R0, were used to assess the soil physical quality of two agricultural areas (cropland and olive orchard) and two natural areas (grassland and managed woodlot plantation) potentially subject to soil degradation. The overall idea of the study was to investigate whether a dynamic indicator quantitatively derived from hydraulic conductivity measurements could be used to supplement the traditionally applied capacitive indicators retrieved from water retention measurements. According to the available criteria, only the surface layer of the cropland site showed optimal …

Multiregression Analysis of the Kinetic Constants in Ephemeral Rivers: The Case Study of the Oreto River

2018

Profuse efforts have been committed to develop efficient tools to measure the ecological status of the receiving water body quality state. The recurrence to mathematical models as support tools for the receiving water body quality assessment can be an optimal choice. Indeed, mathematical models can allow to build-up the cause effect relationship between polluting sources and receiving water quality. Regarding the river water quality modelling, two different kinds of river can be single out: large and small rivers. In the modelling approach, the main differences between the two types of river are reflected in the model kinetic constants. Indeed, the main quality processes which control and g…

An urban drainage stormwater quality model: model development and uncertainty quantification

2010

Summary The evaluation of urban stormwater quality is of relevant importance for urban drainage, and mathematical models may be of great interest in this respect. To date, several detailed mathematical models are available to predict stormwater quantity–quality characteristics in urban drainage systems. However, only a few models take sewer sediments into account, considering their cohesive-like properties that influence the build-up process of the pollutant load. Furthermore, the model data requirements, especially for the quality aspects, are extensive, which limit their applicability and affect model results with large uncertainty. Uncertainty analysis provides a measure or index regardi…