Search results for "Land use"
showing 10 items of 333 documents
Short-Term Electricity Futures Prices: Evidence on the Time-Varying Risk Premium
2008
This paper examines empirically the relationship between electricity spot and futures prices, by analysing a decade of data for a set of short term-to-maturity futures contracts traded in the Nordic Power Exchange, Nord Pool. It is found that, on average, there are significant positive risk premiums in short-term electricity futures prices. The significance and size of the premiums, however, varies seasonally over the year; whereas it is greatest during winter, it is zero in summer. It is also found that time-varying risk premiums are significantly related to unexpectedly low reservoir levels. Furthermore, before the unprecedented supply-shock that hit the Nord Pool market around the end of…
Land Use History and Site Formation Processes at the Punic Site of Pauli Stincus in West Central Sardinia
2013
The site of Pauli Stincus is located near the town of Terralba, on the inland shores of the Gulf of Oristano in west central Sardinia, Italy, and was occupied between the mid-4th and the late 2nd century B.C. The site and its surroundings were the object of a joint archaeopedological and geomorphological study, which complemented the data from archaeological excavations. This study allowed us to evaluate the suitability of the different landscape and soil components for crop production in the Punic period. The discovery of a buried plow soil at the site's edge enabled us to identify a set of agricultural practices carried out by Punic farmers. These included the removal of sandy topsoil to …
Shifts in microbial diversity through land use intensity as drivers of carbon mineralization in soil
2015
10 pages; International audience; Land use practices alter the biomass and structure of soil microbial communities. However, the impact of land management intensity on soil microbial diversity (i.e. richness and evenness) and consequences for functioning is still poorly understood. Here, we addressed this question by coupling molecular characterization of microbial diversity with measurements of carbon (C) mineralization in soils obtained from three locations across Europe, each representing a gradient of land management intensity under different soil and environmental conditions. Bacterial and fungal diversity were characterized by high throughput sequencing of ribosomal genes. Carbon cycl…
Relationships between earthworm communities and burrow numbers under different land use systems
2010
International audience; This study addresses the influence of three different land use systems (continuous maize, pasture/maize rotation, permanent pasture) on the relationships between earthworm populations and the number of earthworm burrows quantified in a soil profile. Quantified burrows were limited to those observable by the naked eye (i.e. >2 mm in diameter) and enumerated earthworms were limited to those which could have created the observable burrows (i.e. >0.3 g). The results were combined with data from the literature coming from different geographical regions. This study showed that earthworm abundance decreased with the increasing land management intensity (maize crop vs. pastu…
Testing the “physical model concept” by soil loss data measured in Sicily
2012
The best possible model to predict the erosion from an area of land has been suggested to be a physical model of the area that has similar soil type, land use, size, shape, slope and erosive inputs. Therefore, a replicated plot has to be considered the best possible, unbiased, real world model. In this paper the physical model concept was tested by using soil loss data collected on plots of different length at the experimental station of Sparacia, in Sicily (South Italy). This investigation supported the conclusions that i) a coefficient of determination between measured and predicted soil loss values of 0.77 has to be considered as the best-case prediction scenario and ii) an uncalibrated …
Historical Perspectives on Soil Mapping and Process Modeling for Sustainable Land Use Management
2017
Basic soil management goes back to the earliest days of agricultural practices, approximately 9000 BCE. Through time humans developed soil management techniques of ever increasing complexity, including plows, contour tillage, terracing, and irrigation. Spatial soil patterns were being recognized as early as 3000 BCE, but the first soil maps did not appear until the 1700s and the first soil models finally arrived in the 1880s. The beginning of the 20th century saw an increase in standardization in many soil science methods and wide-spread soil mapping in many parts of the world, particularly in developed countries. However, the classification systems used, mapping scale, and national coverag…
Goal Oriented Soil Mapping
2017
Abstract Soil mapping is very important for the correct implementation of sustainable land use management. In recent decades, soil mapping methods and data availability have increased exponentially, improving the quality of the maps produced. Despite these advances, local knowledge is a great source of information, refined for centuries and useful for soil mapping and the implementation of a sustainable land management. Local wisdom and experience should be an important aspect of soil mapping because farmers will be one of the major end-users of the maps produced and they should account for the farmers’ reality. However, several problems have been identified in the spatial correlation betwe…
Assessment of soil suitability for improvement of soil factors and agricultural management
2019
The dramatic growth of the world&rsquo
Land Surface Temperature
2019
Abstract An introduction to the chapter on Land Surface Temperature (LST). The basic thermal infrared theory is presented with example algorithms for the retrieval of LST and emissivity data are described in the later section. Various methods to validate satellite Land Surface Temperature (LST) products exist, but the most accurate and conclusive method is the direct comparison against in situ LST obtained from spatially representative radiance measurements over homogeneous sites. Some validation results and insights found in the literature are provided and the determination of in situ emissivity and LST with thermal infrared field radiometers is explained. The chapter concludes with an exa…
Determining the potential impacts of fire and different land uses on splash erosion in the margins of drylands
2021
Abstract This research aimed to estimate the splash erosion and its evolution during the first months in specific land uses after a forest fire. The study area was located in Congosto (North-West Spain), in the margins of Spanish drylands, after a wildfire occurred in May 2012, which burned 15.56 ha of scrubland and Pinus reforestation. Two different burned land uses were selected and compared to control areas: i) burned pine forest; and, scrublands. Rainfall intensity and the number, sizes and speed of raindrops were measured by an optical disdrometer and soil loss by funnels. Moreover, infiltration, soil moisture content, aggregate stability, water repellence, pH and organic matter were a…