Over the last few years, the impacts of wildlife on agriculture have constantly been growing, in particular in areas close to woodland and in hunting ban zones (“refuge effect”). Public administrations have difficulty in meeting the growing requests for crop damage compensation. The development of appropriate measures to control this trend—starting from the understanding of the dynamics concerned—is crucial. The aim of this study was, therefore, to analyze damage at regional scale and define common local actions. In particular, the study involved different steps that define a spatial-based classification of risk levels, integrating statistical methods (principal component analysis and receiver operating characteristic) with multi-criteria evaluation (MCE) in a geographic information system (GIS). It turns out that, in the study area, the very high-risk zones affect 8.83% of used agricultural areas; about 97% of them concentrated in the first 400 m from the most suitable habitats. A selected cluster of 11 test areas within these zones allowed us to assess the cost-effectiveness of integrated prevention and control actions (IPCA) with respect to the compensation of the damage. The analysis shows cost of IPCA to be nearly twice the actual cost incurred by the public administration to compensate partially the damage. The comparison with the estimated damage shows the overall economic convenience of the proposed investment with significant differences depending on the areas. Thus, we suggest reaching an “agro-ecological” balance starting from actions on specific areas; if they produce the desired effects, they could be progressively extended to other areas with gradual investments (adaptive management).
The Kamchatka peninsula, located in the far east of Russia, is a geologically active margin where the Pacific plate subducts beneath the North American and Eurasia plates. This area is characterised by frequent and strong seismic activity (magnitudes up to 8.5) and epicentres are generally distributed offshore along the eastern coast of the peninsula. For many years, hydrogeochemicals have been collected with a mean sampling frequency of three days in the form of the flow rate and the most common ions and gases in the groundwater of three deep wells in the southern area of the Kamchatka peninsula, where the capital city Petropavlovsk is located. Beginning in 1988, five earthquakes with M > 6.5 occurred in this area. These earthquakes were powerful enough to be considered as potential precursor sources in the sense that the stresses and strains building up before them might be expected to cause precursory activity. In order to reveal any possible precursors of these earthquakes, we analysed the hydrogeochemical data collected. We considered any signal having an amplitude three times the standard deviation to be an irregularity and we defined as an anomaly the existence of an irregularity occurring simultaneously in more than one parameter at each well. Then, on the basis of the worldwide past results and the time recurrence of the quoted earthquakes, we chose 158 days as the maximum temporal window between a possible anomaly and the subsequent earthquake. We identified some premonitory anomalies in hydrogeochemical parameters at different wells. On the basis of these results some earthquake forecasting criteria in southern Kamchatka may be tentatively formulated 相似文献
Phosphorus (P) is an essential nutrient required for plant growth and at the same time a costly pollutant, which can cause eutrophication of water bodies. Modern agriculture relies heavily on mineral fertilisers, which contain phosphorus derived from phosphate rock, because, without regular applications, crop yields would be limited. Since phosphate rock is a non-renewable resource, there are growing concerns regarding future phosphorus scarcity and the sustainability of modern agriculture. For many farmers, animal manure was once a means of maintaining soil fertility, but now it presents a major operational problem. This study evaluated the possibility of recycling phosphorus on a national and regional scale in Italy, using major sources of manure and wastewater. These results were successively compared with an estimate of the agricultural demand for phosphorus. Considering the quantity of phosphorus fertilizer that was applied to the soil–plant system, for the years 2001–2010, the annual phosphorus requirement of Italian crops was about 101,000 t of P. Therefore, the phosphorus source comprising animal manure and civil/industrial waste (117,500 t of P and 40,000 t of P, respectively) could potentially satisfy the average annual agronomic phosphorus demand. Regarding the geographical distribution of phosphorus supply and demand on a regional scale, areas with a large deficit of phosphorus included Calabria, Puglia and Marche. However, when only livestock waste was considered, Sicily, Umbria and Friuli could also be considered to be regions experiencing a phosphorus deficit.
Meteoric smoke particles (MSPs) form through the vaporization of meteoroids and the subsequent re-condensation of metallic species in the mesosphere. Recently, iridium and platinum enrichments have been identified in Greenland ice layers and attributed to the fallout of MSPs supplying polar latitudes with cosmic matter during the Holocene. However, the MSP fallout to Antarctica during the Earth's climatic history remains essentially unknown.
We have determined iridium and platinum in deep Antarctic ice from Dome C and Vostok dated back to 240 kyrs BP. We find high super-chondritic fluxes during warm periods and low meteoric accretion during glacial times, a pattern that is opposite to any known climatic variation in dust fallout to polar regions. The proposed explanation of this accretion regime is a weaker polar vortex during warm periods, allowing peripheral air masses enriched in volcanic iridium and platinum to penetrate inland to Antarctica. The MSP signal emerges only during cold phases and is four times lower than in the Greenland ice cap where more snow accumulates. This suggests that wet deposition is an important route of cosmic material to the Earth's surface. 相似文献
Runoff and nutrient transport by rivers were analysed in the Northern Adriatic continental shelf, in order to evaluate their interannual and multidecal variability, as well as their current contribution to determine freshwater and nutrient budgets in this marine region. During the years 2004-2007, the runoff in the basin (34.1-64.6 km3 yr−1) was highly imbalanced, being 84% of freshwater discharged along the western coast, because of the contributions of Po, Adige and Brenta rivers. In the northern and eastern sections of the coast, freshwater discharge by rivers was less important (10 and 6%, respectively), but not negligible in determining the oceanographic properties at sub-regional scales. The oscillations of the transport of biogenic elements (124-262×103 t N yr−1 for TN, 72-136×103 t N yr−1 for DIN, 4.5-11.1×103t P yr−1 for TP, 2.2-3.5×103 t P yr−1 for PO4 and 104-196×103 t Si yr−1 for SiO2) were strictly dependant to the differences in the annual runoff. A strong excess of N load in comparison to P load characterised all rivers, both in inorganic nutrient (DIN/PO4=37-418) and total (TN/TP=48-208) pools, particularly in the northern and eastern areas of the basin.The annual runoff showed significant oscillations for Po on multidecadal time scale, whereas a general decrease (−33%) was observed for the other N Adriatic rivers as the recent discharges were compared to those before the 1980s. During the dry years 2005-2007, a strong reduction of river water flows and nutrient loads was experienced by the N Adriatic ecosystem with respect to years characterised by medium-high regimes. An increased frequency of similar drought periods, due to ongoing climate changes or to a larger human usage of continental waters, would be easily able to significantly change the biogeochemistry of this basin. 相似文献
The Late Neoproterozoic Buah Formation (Nafun Group, Oman) is a carbonate unit outcropping in the Jabal Akhdar and Huqf areas. It is composed mostly of shallow‐water carbonates deposited on a distally steepened carbonate ramp. Correlation of two δ13C isotope shifts shows that in the Jabal Akhdar ramp differentiation into fast and slow subsiding areas was followed by lateral progradation. In the Huqf area, however, a uniform scenario of upward shallowing of the facies and lateral progradation is demonstrated by chemostratigraphic timelines cross‐cutting the facies belts. The chemostratigraphic profiles show that the Buah Formation was deposited during sea‐level highstand conditions and that ramp differentiation was due to synsedimentary tectonics. High‐resolution correlation of δ13C profiles from the same lithostratigraphic unit (whether Precambrian or Phanerozoic in age) lacking biostratigraphic data can shed light on carbonate systems dynamics, tectonic vs. eustatic controls on depositional sequences and basin subsidence. 相似文献
Sedimentary rocks deposited during the Ediacaran period (～630–542 Ma) contain carbonates whose carbon isotopic ratios show a marked negative excursion consisting of a precipitous drop from +5‰ to ?12‰, followed by a sub‐linear recovery to positive δ13C values. Isotopic ages (U/Pb) and thermal subsidence modelling are combined to constrain the excursion in time and indicate an onset at ～600 Ma, and duration of recovery of approximately 50 Myr. The excursion is widely recognized in Oman and has potential correlatives in Ediacaran strata elsewhere, and may thus represent a characteristic feature of the Ediacaran period. The amplitude of this carbon isotope excursion far exceeds those of other Neoproterozoic anomalies. The isotopic trend of negative excursion and long‐term recovery spanned at least one short‐lived glacial episode (at 580 Ma), but appears unrelated to glaciation, which indicates that negative anomalies in the Neoproterozoic marine carbon isotope record are not directly or uniquely linked to ice ages. 相似文献
—The Gran Sasso chain (Central Apennines, Italy) contains one of the largest aquifers of Central Italy. From 1970–1986 the massif was tunnelled through in order to build up a highway and an international underground laboratory for nuclear physics research. These works have strongly modified the hydrogeological situation of the chain, as shown by the decrease in flow rate that occurred in many springs located at the border of the carbonatic structure, along the boundary between the permeable limestone of the massif and the surrounding aquicludes. The analysis of the seismicity (M≥ 3.0) that occurred in the Gran Sasso area from 1956 to 1995 suggests that after the tunnelling works both the number of earthquakes has increased and epicenters have migrated, gathering at the northwestern border zone. The foremost events which occurred in this zone in recent years took place on May 5, 1992 (M = 3.1), August 25, 1992 (M = 3.9) and March 13, 1994 (M = 3.5). The flow rate data of four springs and water level data of an underground karst pool located at the border of the carbonatic structure of the massif show clear anomalies before the occurrence of the quoted earthquakes. Regardless, these anomalies can be explained by the rapid melting of the thick mantle of snow on the Gran Sasso chain, due to sudden increases of mean temperatures. In this paper we present and discuss the possibility that the quoted earthquakes are induced by the irregular variations of the Gran Sasso aquifer, evidenced by the quoted anomalies in the flow rate and water level. 相似文献
Cr, Fe, Rb, Ba and U were determined by inductively coupled plasma sector field mass spectrometry (ICP-SFMS) in various sections of the 3,270 m deep ice core recently drilled at Dome C on the high East Antarctic plateau as part of the EPICA program. The sections were dated from 263 kyr bp (depth of 2,368 m) to 672 kyr bp (depth of 3,062 m). When combined with the data previously obtained by Gabrielli and co-workers for the upper 2,193 m of the core, it gives a detailed record for these elements during a 672-kyr period from the Holocene back to Marine Isotopic Stage (MIS) 16.2. Concentrations and fallout fluxes of all elements are found to be highly variable with low values during the successive interglacial periods and much higher values during the coldest periods of the last eight climatic cycles. Crustal enrichment factors indicates that rock and soil dust is the dominant source for Fe, Rb, Ba and U whatever the period and for Cr during the glacial maxima. The relationship between Cr, Fe, Rb, Ba and U concentrations and the deuterium content of the ice appears to be similar before and after the Mid-Brunhes Event (MBE, around 430 kyr bp). Mean concentration values observed during the successive interglacials from the Holocene to MIS 15.5 appear to vary from one interglacial to another at least for part of the elements. Concentrations observed during the successive glacial maxima suggest a decreasing trend from the most recent glacial maxima (MIS 2.2 and 4.2) to the oldest glacial maxima such as MIS 14.2, 14.4 and 16.2, which could be linked with changes in the size distribution of dust particles transported from mid-latitude areas to the East Antarctic ice cap. 相似文献
Neoproterozoic carbonates are known to show exceptional variations in their carbon isotopic ratios, and in the absence of biostratigraphy and a firm geochronological framework, these variations are used as a correlation tool. However, it is controversial whether the carbon isotope record reveals a primary oceanographic signal or secondary effects such as diagenesis. The Shuram Formation of the Nafun Group of Oman allows a stratigraphic test of this problem. The Nafun Group (Huqf Supergroup, Oman) in the Huqf area of east-central Oman consists of inner carbonate ramp facies of the Khufai Formation overlain by marine, storm-generated, red and brown siltstones of the Shuram Formation. Towards its top, the Shuram Formation is composed of distinctive shallowing-upward, 4–17-m-thick parasequences cropping out continuously over 35 km, which show recessive swaley cross-stratified siltstones capped by ledges comprising wave-rippled, intraclast-rich ooidal carbonate. These storm-dominated facies show a regional deepening in palaeobathymetry towards the south. The carbonates of the Shuram Formation are marked by an extreme depletion in 13C in bulk rock. δ13C values quickly reach a nadir of −12‰ just above the Khufai-Shuram boundary and steadily return to positive values in the overlying mainly dolomitic Buah Formation. The Shuram excursion is thought to be ca . 50 Myr in duration and extends over 600 m of stratigraphy. Carbon isotopic values show a systematic variation in the parasequence stack, with values varying both vertically through the stratigraphy (∼2‰ per 45 m) and laterally in the progradation distance (∼1‰ over 35 km). This supports a primary, oceanographic origin for these extremely negative carbon isotopic values and independently argues strongly against diagenetic resetting. 相似文献
