Modeling the deterioration of natural resources, especially water and soil that results from the global effects of climate change has become a powerful tool in the search for mitigation and adaptation measures. The objectives of this research were: (1) to model the potential impact of climate change for the period 2010-2039, and (2) to offer advice about future risks based on local radiative forcing or critical areas and taking into account two indicators of environmental quality, the aridity index (AI) and laminar wind erosion (LWE). Evaluation techniques for natural resources, similar to those applied by the Instituto Nacional de Ecología y Cambio Climático (National Institute of Ecology and Climate Change) were used for studies of ecological land use. The inputs include climate information (current and future), soil cover and edaphic properties related to the municipality of Gómez Palacio, Durango, Mexico (25.886° N, 103.476° W). According to calculations estimated from the anomalies for the mean annual rainfall and mean annual temperature, in a future climate change scenario, an average impact of approximately 63% would be caused by LWE, and the AI would change from its historical value of 9.3 to 8.7. It is estimated that the average impact on the AI in the future will be 0.53 ± 0.2. 相似文献
Natural Hazards - Extreme risks associated with natural and man-made disasters involve disruptions to the production of goods or provision of services in interdependent systems. The reduced supply... 相似文献
AbstractThe objective of this study is to analyse three rainfall–runoff hydrological models applied in two small catchments in the Amazon region to simulate flow duration curves (FDCs). The simple linear model (SLM) considers the rainfall–runoff process as an input–output time-invariant system. However, the rainfall–runoff process is nonlinear; thus, a modification is applied to the SLM based on the residual relationship between the simulated and observed discharges, generating the modified linear model (MLM). In the third model (SVM), the nonlinearity due to infiltration and evapotranspiration is incorporated into the system through the sigmoid variable gain factor. The performance criteria adopted were a distance metric (δ) and the Nash-Sutcliffe coefficient (R2) determined between simulated and observed flows. The good results of the models, mainly the MLM and SVM, showed that they could be applied to simulate FDCs in small catchments in the Amazon region.Editor D. Koutsoyiannis; Associate editor A. MontanariCitation Blanco, C.J.C., Santos, S.S.M., Quintas, M.C., Vinagre, M.V.A., and Mesquita, A.L.A., 2013. Contribution to hydrological modelling of small Amazonian catchments: application of rainfall–runoff models to simulate flow duration curves. Hydrological Sciences Journal, 58 (7), 1–11. 相似文献
A flow of key information links marine spatial planning (MSP) and oil spill risk analysis (OSRA), two distinct processes needed to achieve true sustainable management of coastal and marine areas. OSRA informs MSP on areas of high risk to oil spills allowing a redefinition of planning objectives and the relocation of activities to increase the ecosystem’s overall utility and resilience. Concomitantly, MSP continuously generates a large amount of data that is vital to OSRA. The Environmental Sensitivity Index (ESI) mapping system emerges as an operational tool to implement the MSP–OSRA link. Given the high level of commonalities between ESI and MSP data (both in biophysical and human dimensions), ESI tools (both paper maps and dynamic GIS-based product) are easily developed to further inform MSP and oil spill risk management. Finally, several other benefits from implementing the MSP–OSRA link are highlighted. 相似文献
The spatial distribution and diel vertical migration of fish larvae were studied in relation to the environmental conditions off NW Iberia during May 2002. Larvae from 23 families were identified, the most abundant were the Clupeidae, Gobiidae, Callionymidae, Blenniidae, Sparidae and Labridae. Sardina pilchardus was the most abundant species, mean concentrations 1 order of magnitude higher than the other fish larvae species. Larval horizontal distribution was mainly related to upwelling-driven circulation, resulting in an offshore increase of larval abundance while the vertical distribution was closely associated to the Western Iberia Buoyant Plume. Despite this general trend, taxon-specific relationships between the distribution of larvae and environmental variables were observed, and temperature was an important regressor explaining the distribution of most taxa. A comparison between ichthyoplankton samples collected alternatively with the LHPR and Bongo nets resulted in captures of larvae ≈1 order of magnitude higher for the LHPR, probably related to its higher towing speed. The spatial distribution and relative composition of larvae were also different for both nets, although the most frequent/abundant groups were the same. A fixed station sampled for 69-h showed diel vertical migrations performed by the larvae, with the highest larval concentrations occurring at surface layers during the night and most larvae being found in the neuston layer only during that period. 相似文献
The assessment of vulnerability provides valuable knowledge in the risk assessment steps of a risk governance process. Given the multiscale, multilevel, and multisectorial aspects of flood risk, the diversified entities that directly and indirectly intervene in risk management require specific outputs from the assessment studies. Urban areas in estuarine margins are particularly exposed and vulnerable to flooding. Such interface conditions are found in the Old City Centre of the Seixal, located in the Tagus estuary, Portugal. Here, two distinct methodologies were applied for the assessment of territorial vulnerability. A regional, lower-scale, methodology explores the application of the statistical procedure based on the SoVI® at the statistical block level. A second, local and higher-scale, methodology is based in data collected through field matrices at the building and statistical sub-block level. Comparison of results revealed that the lower-scale assessment provides information on the vulnerability drivers at the regional and municipal level. Nevertheless, only at a higher-scale, it is possible to characterize and differentiate the smaller geographical units of analysis that compose the Old City Centre of Seixal. The lower-scale vulnerability assessment allows a strategic response, based on adaptation measures such as spatial planning, institutional capacity building and public awareness. The local level assessment provides more accurate knowledge to support local emergency planning and the allocation of operational and material resources at the urban level. Nevertheless, rather than antagonistic, both models can be considered as complementary, having in mind the requirements of an holistic flood risk governance model.
The Gurupi Belt hosts a Paleoproterozoic gold province located in north–northeastern Brazil, at the borders of Pará and Maranhão states. It is considered to be an extension of the prolific West African Craton’s Birimian gold province into South America. Additionally, the belt has been the object of recent mineral exploration programs with significant resource discoveries. This study presents the results of predictive mapping using up-to-date mineral system concepts and recently finished regional-scale geological mapping, stream sediment and airborne geophysical surveys conducted by the Geological Survey of Brazil. We relate gold mineralization to an initially enriched crust, metamorphism, deep fluid pathways, structurally controlled damage zones and hydrothermal alteration. Prospective targets were generated using only regional public datasets and knowledge-driven targeting technique. This work did not incorporate any known gold deposits, yet it predicted the largest known deposits and their satellite targets. Besides, high prospective targets mapped almost 40% of known primary gold occurrences within 7% of the project area. This work allowed considerable search area reduction and identification of new target areas, thus collaborating on reducing costs, time and risk of mineral exploration. Results indicate that we achieved an efficient understanding of the geological processes related to the Gurupi Belt mineral system. 相似文献
The present study is an approach to detect the sea/freshwater interface in Sidi Abdel Rahman area, northwestern coast of Egypt using both vertical electrical sounding and time domain electromagnetic. The measured vertical electrical soundings are interpreted in 1D and 2D manner. The 1D inversion is carried out using the commercial software (RESIST), whereas 2D resistivity nonlinear iterative inversion scheme based on the finite element technique and regularization method was used. The time domain electromagnetic stations are interpreted using Temixxl-4 software by Interpex Ltd. To have the advantages of the vertical electrical sounding in shallow depths and time domain electromagnetic in deep depths, a joint inversion algorithm is applied for the electric profile and the nearby electromagnetic profile. Very low resistivity values have been observed near the coast as well as a considerable salt/fresh water interface. The tip-top portion of the interface lies approximately 1,000 m from the shore line. 相似文献
The physical and chemical changes in sediment and near bottom water caused by clam dredging were examined during July and September 1999, at two locations Vilamoura (VL) and Armona (AR), south coast of Portugal. Sediment cores and near bottom water were collected simultaneously before dredging (control samples) and within short time intervals (min-h) after dredging. After dredging operations, microphytobenthos coming from the path were accumulated in the re-worked sediment (ridge). Chlorophyll a in superficial sediment increased from 1.2 microg x g(-1) before dredging to 1.7 microg x g(-1) after dredging and these higher values remained for a few hours. However, the expected increase of chlorophyll a in near bottom water due to re-suspension was not observed. After sediment disturbance an instantaneous sorption of phosphorus onto iron oxides occurred in the upper sediment layers (from 2 to 3 micromol x g(-1) before dredging to 4-5 micromol x g(-1) after dredging). A microcosm experiment showed that after sediment disturbance HPO(4)(2-) dissolved in pore water decreased from 40 to 10 microM being simultaneously sorbed onto iron oxides formed in the top layer of sediment. The ammonium, nitrates, organic nitrogen, phosphate and silicate dissolved in pore water decreased immediately after dredging activity and simultaneously an increase in near bottom water was sporadically observed. Generally, the re-establishment of seabed was reached within a short time (min-h), at both stations (VL and AR). 相似文献