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In Italy quarrying causes relevant environmental damages and alterations to the land and the ecosystems. Despite the present Italian legislation requiring the restoration of the sites after exploitation, most of the quarries, both the abandoned and the still operational ones, are not restored.The objective of this work is to indicate a monitoring methodology in order to survey the present state of the quarry sites and their evolution in time, which are the basic data needed to implement an adequate land reclamation project.Such methodology has been applied to several abandoned limestone quarries in the Latina province (close to Rome), characterised by a typical Mediterranean vegetation, but it can be applied to any other kind of litology and vegetation.The land monitoring has been realised both by using remote sensing techniques, supported by a Geographic Information System of the studied area, and by in situ surveying. The in situ surveying was able to assess the capability of the remote sensing model to describe the state of each site.  相似文献   
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The aim of the research presented here was to analyse soil erosion in response to changes in agricultural and soil conservation practices throughout history. The Aksum area (Tigray, northern Ethiopia) presents favourable conditions for the development of a long-term approach for assessing soil conservation techniques that have been applied for centuries (i.e., since the Aksumite kingdom, 400 BC to 800 AD). These techniques have been maintained until the present day, and parts of the terraced systems of the area are still in use. During the 1970s, social and political events led to a remarkable change in land use patterns, and large arable areas were converted into grazing land, resulting in a significant increase in soil loss. The rates of soil erosion were evaluated based on analyses of the deep scratches (plough marks) left on stones in the soil by the maresha, the ard plough pulled by oxen used in agricultural practices of the area, and the patinas, varnishes and weathering rinds exposed by soil loss after the abandonment of the fields. The study results show average rates of soil erosion of 2.8 t ha−1 y−1 and 65.8 t ha−1 y−1 for the soil conservation conditions under traditional agriculture (long-term observations) and accelerated erosion after abandonment (short-term observations), respectively. A comparison using recently calibrated erosion evaluation techniques conducted to support the field measurements revealed a close correlation between the calculated and recorded data.  相似文献   
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Concerns over water scarcity, climate change, and environmental health risks have prompted some Asian cities to invest in river rehabilitation, but deciding on the end goals of rehabilitation is a complex undertaking. We propose a multidisciplinary framework linking riparian landscape change to human well‐being, providing information relevant to decision makers, in a format that facilitates stakeholder involvement. We illustrate this through a case study of the densely settled, environmentally degraded, and flood prone Ciliwung River flowing through metropolitan Jakarta, Indonesia. Our methodology attempts to respond to this complexity through an iterative approach, strongly based on conceptualization and mathematical modeling. Nested hydrologic, hydrodynamic, and water quality models provide outputs at catchment‐, corridor‐, and localized site‐scales. Advanced 3‐D landscape modeling is used for procedural design and precise visualization of proposed changes and their impacts, as predicted by the mathematical models. Finally, participatory planning and design methods allow us to obtain critical stakeholder feedback in shaping a socially acceptable approach. Our framework aims at demonstrating that a change in paradigm in river rehabilitation is possible, and providing future scenarios that balance concerns over flooding, water quality, and ecology, with the realities of a rapidly growing megacity.  相似文献   
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Lead and cadmium concentrations in spontaneous vegetation and in soil sampled at various distances (0–208 m) from several motorways throughout Italy were measured. Lead and cadmium concentrations appear to be correlated to distance from the motorway and to traffic levels. A comparison with data from a remote and unpolluted site shows that foliar lead concentrations can be up to 40 times higher, and foliar cadmium concentrations up to 3 times higher. Plants behave differently in their accumulation of lead and cadmium; conifers present the highest levels. Also the various receptors and compartments of the roadside ecosystem differ in their accumulation of lead and cadmium; soil and bark have consistently higher concentrations, while the leaves and twigs of trees have consistently lower levels. the data recorded by ad hoc introduced bio-accumulating plants (Lolium multiflorum L.) are consistent with those of the spontaneous vegetation. the concentrations of both lead and cadmium in Lolium vary from June to November, following in part the fluctuation in traffic density.  相似文献   
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We describe the first case of mosaic supernumerary marker iso (8p) displaying a karyotype discordance between chorionic villi (CV) and amniotic fluid (AF) cultures during prenatal cytogenetic diagnosis. In the first trimester, cytogenetic analysis after chorionic villi sampling (CVS) was normal in all metaphases in the short-term cytotrophoblast cell culture, but an undefined supernumerary marker was detected in 60% of mesenchymal cells in the long-term CV culture. Informed of the mosaicism, the couple selected amniotic fluid sampling as a second-trimester confirmatory diagnostic procedure. The supernumerary marker was absent in all of the 25 available AF cells metaphases. The prospective parents received genetic counselling and were informed that the discordance could be interpreted as a placental confined mosaicism or as a true foetal mosaicism with low percentage of affected cells. The couple opted to continue the pregnancy. In the second month of life, the child had abnormal development with severe psychomotor delay and frequent episodes of epilepsy. Postnatal cytogenetic extensive re-evaluation discovered that the previously detected supernumerary marker was indeed an isochromosome (8p) rearrangement present at low frequency in 5% of the blood lymphocytes. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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