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11.
Quantitative analysis of the impact of droughts and floods on internal wars in China over the last 500 years 总被引:1,自引:0,他引:1
Although many large-N quantitative studies have evidenced the adverse effects of climatic extremes on social stability in China during the historical period, most of them rely on temperature and precipitation as major explanatory variables, while the influence of floods and droughts on social crises is rarely measured. Furthermore, a comparison of the climate-society nexus among different geographic regions and at different temporal scales is missing in those studies. To address this knowledge gap,this study examines quantitatively the influence of floods and droughts on internal wars in three agro-ecological(rice, wheat,and pastoral) regions in China in AD1470–1911. Poisson regression and wavelet transform coherence analyses are applied to allow for the non-linear and non-stationary nature of the climate-war nexus. Results show that floods and droughts are significant in driving internal wars in historical China, but are characterized by strong regional variation. In the rice region, floods trigger internal wars at the inter-annual and multi-decadal time scales. In the wheat region, both floods and droughts cause internal wars at the inter-annual and multi-decadal time scales. In the pastoral region, internal wars are associated with floods only at the multi-decadal time scale. In addition, the multi-decadal coherence between hydro-climatic extremes and internal wars in all three of the agro-ecological regions is only significant in periods in which population density is increasing or the upper limit of regional carrying capacity is being reached. The above results imply that the climate-war nexus is mediated by regional geographic factors such as physical environmental setting and population pressure. Hence, we encourage researchers who study the historical human-climate relationship to boil down data according to geographic regions in the course of statistical analysis and to examine each region individually in follow-up studies. 相似文献
12.
B. B. Cruz L. A. Manfré D.S. Ricci D. Brunoro L. Appolinario Jr. J. A. Quintanilha 《Environmental Earth Sciences》2017,76(12):441
Water resources availability is increasingly constrained, considering the quality and quantity available for use. There is an urgent need of recovering this availability, focusing on the planning and management process of water supply systems. One of the main threats to water resources is related to erosion effects, namely widespread pollution load and the silting of watercourses and reservoirs useful life reduction. The objective of this study was to evaluate water supply systems environmental fragility within the Paulista Macro Metropolis area and to use the results to develop environmental zone classes to orient territorial planning. The study was conducted in seven superficial water supply systems of the aforementioned region. Environmental fragility evaluation was focused on four environmental variables that represent natural vulnerability to erosion, and 2015 land cover map to delineate human influence on erosive processes. Results indicate that Tietê River water supply systems, namely Piracicaba, Capivari and Jundiaí (PCJ) and Itupararanga systems, can be considered the most fragile water supply systems in the study area. The environmental fragility map was used to derive the environmental zoning map, including conservation and priority areas, suitable regions for agriculture expansion, and areas with high needs for restoration efforts. In addition, environmental fragility framework herein can be viewed as a model with high replication potential for regional planning and management in that land cover can be manipulated to minimize environment natural vulnerability, guiding territorial occupation toward a more sustainable landscape design, which subsidizes water resources multiple uses. 相似文献
13.
Gaetano Manfredi Andrea Prota Gerardo Mario Verderame Flavia De Luca Paolo Ricci 《Bulletin of Earthquake Engineering》2014,12(5):2275-2298
Data of the Italian National Institute of Statistics are collected aimed at characterizing Reinforced Concrete (RC) building stock of the area struck by the 2012 Emilia earthquake (number of storeys, age of construction, structural typology). Damage observations, collected right after the event in reconnaissance reports, are shown and analyzed emphasizing typical weaknesses of RC buildings in the area. The evolution of seismic classification for Emilia region and RC buildings’ main characteristics represent the input data for the assessment of non-structural damage of infilled RC buildings, through a simplified approach (FAST method), based on EMS-98 damage scale. Peak Ground Acceleration (PGA) capacities for the first three damage states of EMS-98 are compared with registered PGA in the epicentral area. Observed damage and damage states evaluated for the PGA of the event, in the epicentral area, are finally compared. The comparison led to a fair agreement between observed and numerical data. 相似文献
14.
Marco Benvenuti Marco Bonini Giovanna Moratti Marianna Ricci Chiara Tanini 《Geomorphology》2008,100(3-4):269-284
Integration of geomorphology, stratigraphy, sedimentology and morphotectonics in the analysis of the lower Cecina River reach, coastal Tuscany, reveals an undocumented historical channel avulsion. Geomorphological evidence and radiocarbon dating support that, from the Last Glacial Maximum until the end of the 16th century, the Cecina River flowed north of the present course and formed a well-developed cuspate delta. Two concurrent factors, active tectonics as a preparing factor and discharge regime as an activation factor, are thus inferred to have favored the avulsion of Cecina River. Fragmentary archaeological and historical records indicate that the late Holocene Cecina River plain was virtually unpopulated until the latest 16th century. This seems the main reason why high-magnitude hydrological events and prominent river channel avulsions were not reported in historical chronicles. From this perspective, geomorphological data may provide important knowledge and understanding of recent dynamics of environmental change when historical record is lacking or missing. 相似文献
15.
16.
Procedures for calibration of linear models for damage limitation in design of masonry‐infilled RC frames
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Paolo Ricci Maria Teresa De Risi Gerardo Mario Verderame Gaetano Manfredi 《地震工程与结构动力学》2016,45(8):1315-1335
Recent earthquakes have confirmed the role played by infills in the seismic response of reinforced concrete buildings. The control and limitation of damage to such nonstructural elements is a key issue in performance‐based earthquake engineering. The present work is focused on modeling and analysis of damage to infill panels, and, in particular, it is aimed towards linear analysis procedures for assessing the damage limitation limit state of infilled reinforced concrete frames. First, code provisions on infill modeling and acceptance criteria at the damage limitation limit state are reviewed. Literature contributions on damage to unreinforced masonry infill panels and corresponding displacement capacity are reported and discussed. Two procedures are then proposed aiming at a twofold goal: (i) the determination of ‘equivalent’ interstory drift ratio limits for a bare frame model and (ii) the estimation of the stiffness of equivalent struts representing infill walls in a linear model. These two quantities are determined such that a linear model ensures a reliable estimation of seismic capacity at the damage limitation limit state, providing the same intensity level as that obtained from nonlinear analyses carried out on structural models with infills. Finally, the proposed procedures are applied to four‐story and eight‐story case study‐infilled frames, designed for seismic loads according to current technical codes. The results of these application examples are presented and discussed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
17.
Jean-Baptiste Saulnier Alain Clément Teresa Pontes Pierpaolo Ricci 《Ocean Engineering》2011,38(1):130-147
To date the estimation of long-term wave energy production at a given deployment site has commonly been limited to a consideration of the significant wave height Hs and mean energy period Te. This paper addresses the sensitivity of power production from wave energy converters to the wave groupiness and spectral bandwidth of sea states. Linear and non-linear systems are implemented to simulate the response of converters equipped with realistic power take-off devices in real sea states. It is shown in particular that, when the converters are not much sensitive to wave directionality, the bandwidth characteristic is appropriate to complete the set of overall wave parameters describing the sea state for the purpose of estimating wave energy production. 相似文献
18.
Cave clastic sediments as a tool for refining the study of human occupation of prehistoric sites: insights from the cave site of La Cala (Cilento,southern Italy)
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19.
New records of cold‐water coral sites and fish fauna characterization of a potential network existing in the Mediterranean Sea
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Gianfranco D'Onghia Crescenza Calculli Francesca Capezzuto Roberto Carlucci Angela Carluccio Porzia Maiorano Alessio Pollice Pasquale Ricci Letizia Sion Angelo Tursi 《Marine Ecology》2016,37(6):1398-1422
New cold‐water coral (CWC) sites were recorded along the Apulian margin (Central Mediterranean). The species composition and depth distribution of CWCs were updated. A distribution of the CWC sites coincident with the course of the dense‐water masses that flow between the Southern Adriatic and Northern Ionian was confirmed. The faunal assemblages of five of these CWC sites were investigated and compared using experimental longlines during the spring–summer and autumn–winter seasons, between 2010 and 2014. Differences in ecological variables amongst the sites in each season were evaluated by means of a set of univariate and multivariate methods (analysis of variance, permutational multivariate analysis of variance, non‐metric multidimensional scaling). Although some differences were detected in relation to the different depths examined during spring–summer, the CWC sites showed similar features in terms of species richness and diversity as well as in the abundance of the same fish species (Galeus melastomus, Conger conger, Helicolenus dactylopterus, Merluccius merluccius, Phycis blennoides and Pagellus bogaraveo) most probably because of the distribution of adult specimens in structurally complex and heterogeneous habitats, which act as a potential ‘refuge network’ with respect to commercial fishing. The presence of maturing and mature individuals as well as post‐reproductive females indicates that these CWC sites also act as spawning areas, representing a potential ‘renewal network’ for the fish populations. The term ‘network’ used here refers to several similar subsystems (CWC sites) that play the same ecological role in a wider system (Apulian margin). These CWC communities need coherent conservation measures and management strategies according to the Ecosystem Approach to Fisheries. 相似文献
20.
M. Franceschelli M. Mellini I. Memmi C. A. Ricci 《Contributions to Mineralogy and Petrology》1989,101(3):274-279
Sudoite, the di-trioctahedral chlorite with ideal composition (Mg2Al)(Al2)(Si3Al)O10(OH)8 is a widespread rock-forming mineral in meta-siltstones and psammites of the Verrucano sequence of the Northern Apennines. Sub-ellipsoidal aggregates, probably derived from muscovite clasts, consisting of sudoite, pyrophyllite and muscovite, are common; sudoite may also occur as thin blades in the rock matrix. The co-existence of sudoite, Ferich chloritoid and pyrophyllite, reported here for the first time, has been observed in specimens from the M. Argentario and Monticiano-Roccastrada areas. This three-phase assemblage, diagnostic of a specific metamorphic facies, may be a tool for detailed zonation of low-grade terranes. 相似文献