Multi-temporal assessment of vulnerability to climate change: insights from the agricultural sector in Mexico     

Alejandro Ismael Monterroso-Rivas  Ana Cecilia Conde-Álvarez  José Luís Pérez-Damian  Jorge López-Blanco  Marcos Gaytan-Dimas  Jesús David Gómez-Díaz 《Climatic change》2018,147(3-4):457-473

Vulnerability to climate change was evaluated for three different time periods: 1990, 2000, and 2010. Our objective was to discuss the scope of a multi-temporal assessment of vulnerability. The method used 55 indicators—with emphasis on the agricultural sector in Mexico—of which 27 were updated for the year 2010 and 33 were retrospectively estimated for the year 1990. The results show that in the 20-year study period, the exposure of the municipalities (and inhabitants) has increased, and sensitivity and adaptive capacity have decreased. The number of municipalities vulnerable to climate change declined over the 20-year period. We found that calculating vulnerability by adding exposure and sensitivity and subtracting adaptive capacity (E?+?S???AC) can lead to unintentional underestimation of total vulnerability. When rating vulnerability, care must be taken in what is reported: the results differ for the number of inhabitants versus the number of municipalities. Our previous published vulnerability evaluation was for the year 2000, so we wanted to evaluate the sensitivity of some variables and the vulnerability formula itself we used in that moment. It is possible to evaluate the vulnerability multi-temporally, which allows to evaluate the sensibility and calibration of the variables and indicators used and the reconsideration of their application.  相似文献   

Exchange fluxes of VOSCs between rice paddy fields and the atmosphere in the oasis <Emphasis Type="Bold">of arid area</Emphasis> in Xinjiang,China     

Wei?Wen?JingEmail author  Ning?Li  Xiao?Fang?Li  De?Qiang?Li  Li?Ling?Wang 《Journal of Atmospheric Chemistry》2018,75(1):17-32

Investigations about VOSCs (volatile organic sulfur compounds) have been received increasing attention for their significant contribution to the nonvolcanic background sulfate layer in the stratosphere and the earth’s radiation balance and as a potential tool to understand the carbon budget. In this study, COS and CS₂ were always recorded throughout the entire rice cultivation season of 2014. COS fluxes appeared as emission in non-planted soil and as uptake in planted soil, the corresponding results were obtained as 2.66 and ?2.35 pmol·m^?2·s^?1, respectively. For CS₂, both planted and non-planted paddy fields acted as sources with an emission rate of 1.02 pmol·m^?2·s^?1 and 2.40 pmol·m^?2·s^?1, respectively. COS emission or uptake rates showed a distinct seasonal variation, with the highest fluxes at the jointing-booting stage. COS and CS₂ fluxes increased with increasing N fertilizer use because of improved plant and microbial growth and activity. Plots treated with both N and S reduced COS and CS₂ fluxes slightly compared with plots with only-N treatment. Light, soil moisture or temperature showed no significant correlation with COS and CS₂ fluxes, but revealed the important impacts on the magnitude and direction of gases fluxes. The results also showed that the (available) sulfur contents in soil and roots had a certain effect on VOSCs emission or uptake. Our results highlight the significance of biotic and abiotic production and consumption processes existing in the soil.  相似文献   

Impact of ocean acidification on the carbonate sediment budget of a temperate mixed beach     

Simone Simeone  Emanuela Molinaroli  Alessandro Conforti  Giovanni De Falco 《Climatic change》2018,150(3-4):227-242

The production of sediments by carbonate-producing ecosystems is an important input for beach sediment budgets in coastal areas where no terrigenous input occurs. Calcifying organisms are a major source of bioclastic carbonate sediment for coastal systems. Increased levels of CO₂ in the atmosphere are leading to an increase in the partial pressure of CO₂ on ocean seawater, causing ocean acidification (OA), with direct consequences for the pH of ocean waters. Most studies of OA focus on its impact on marine ecosystems. The impact of OA on carbonate-producing ecosystems could be to reduce the amount of sediments supplied to temperate coastal systems. The aim of this study was to quantify the effect of the predicted OA on the long-term sediment budget of a temperate Mediterranean mixed carbonate beach and dune system. Based on projections of OA we estimated a fall of about 31% in the present bioclastic carbonate sediment deposition rate, with the biggest decreases seen in the dunes (? 46%). OA is also expected to affect the carbonate sediment reservoirs, increasing the dissolution of CaCO₃and causing net sediment loss from the system (~ 50,000 t century^?1). In the long-term, OA could also play a primary role in the response of these systems to sea-level rise. Indeed, the reduction in the quantity of carbonate sediments provided to the system may affect the speed with which the system is able to adapt to sea-level rise, by increasing wave run-up, and may promote erosion of dunes and subaerial beaches.  相似文献   

Biogeographical drivers of ragweed pollen concentrations in Europe     

Matyasovszky  István  Makra  László  Tusnády  Gábor  Csépe  Zoltán  Nyúl  László G.  Chapman  Daniel S.  Sümeghy  Zoltán  Szűcs  Gábor  Páldy  Anna  Magyar  Donát  Mányoki  Gergely  Erostyák  János  Bodnár  Károly  Bergmann  Karl-Christian  Deák  Áron József  Thibaudon  Michel  Albertini  Roberto  Bonini  Maira  Šikoparija  Branko  Radišić  Predrag  Gehrig  Regula  Rybníček  Ondřej  Severova  Elena  Rodinkova  Victoria  Prikhodko  Alexander  Maleeva  Anna  Stjepanović  Barbara  Ianovici  Nicoleta  Berger  Uwe  Seliger  Andreja Kofol  Weryszko-Chmielewska  Elżbieta  Šaulienė  Ingrida  Shalaboda  Valentina  Yankova  Raina  Peternel  Renata  Ščevková  Jana  Bullock  James M. 《Theoretical and Applied Climatology》2018,133(1-2):277-295

Theoretical and Applied Climatology - The drivers of spatial variation in ragweed pollen concentrations, contributing to severe allergic rhinitis and asthma, are poorly quantified. We analysed the...  相似文献   

Crowdsourcing a cyclist perspective on suggested recreational paths in real-world networks     

Kevin Baker  Kristien Ooms  Steven Verstockt  Pascal Brackman  Philippe De Maeyer  Rik Van de Walle 《制图学和地理信息科学》2017,44(5):422-435

ABSTRACT

Routing and navigation services for leisure activities are conditioned by special needs and trade-offs. The advent of online communities and large crowdsourced datasets offers opportunities to improve the adoption of a user’s perspective in these suggested paths. This paper focuses on achieving two goals. First, the presented methodology analyses a dataset of 190,610 historical GPS traces to gain insights into the appreciation or attractiveness of each edge in a real-world network for a specific leisure activity (i.e. road cycling). Second, as literature on these leisure activities is still sparse, we want to create a thorough understanding of the activities at hand for future work. An appreciation model is proposed and the spread of this score is analyzed in shortest-path alternatives of popular routing engines for this activity. This analysis successfully discriminates these shortest paths based on the scoring value and three morphological parameters of the path. However, the robustness of the model should be improved to ensure the viability of the proposed approach in future work. More specifically, further research on the local optimality of the route choices will be imperative.  相似文献   

上海都市区边界划分——基于手机信令数据的探索   总被引：5，自引：0，他引：5  

王德  顾家焕  晏龙旭 《地理学报》2018,73(10):1896-1909

都市区是中心城市及其主要影响范围,在区域经济发展中有重要的引领作用。国外都市区范围根据中心城市与外围地区的通勤联系划分,本质上是与中心城市具有密切经济联系的统一劳动市场区。国内由于统计数据的缺乏,通过通勤联系划分都市区的相关研究难以开展,且划分结果在内涵上与国外都市区差异较大。移动电话是目前普及率最高的移动通讯终端设备,其包含的地理位置标签可反映用户的职住地信息。利用上海移动2014年上半年某两周2G手机信令数据,识别用户的居住地和工作地,参照国外标准,根据中心与外围地区的通勤联系划分上海市都市区。在通勤联系的基础上,尝试采用消费联系作为都市区划分的辅助标准,并对划分结果进行了调整。结果表明：① 基于通勤联系的上海都市区主要包括中心城周边地区、松江新城及外围大型工业区,基于消费联系调整的上海都市区包括中心城周边地区、松江、嘉定、青浦等新城及浦东惠南地区、长兴岛,整体上呈现东西略长、南北略窄的形态;② 通勤联系和消费联系可以相互结合划分中国的都市区边界,通勤联系作为主要指标,消费联系作为辅助指标;③ 上海与国外城市都市区差异较大,国外都市区范围扩展极广,上海都市区范围未超过行政边界,局限在在中心城周围相对较小的范围内。  相似文献   

Active faulting and seismicity along the Siculo–Calabrian Rift Zone (Southern Italy)     

S. Catalano  G. De Guidi  C. Monaco  G. Tortorici  L. Tortorici   《Tectonophysics》2008,453(1-4):177

Southern Italy is dominated by extensional tectonics that in the Calabrian arc and Eastern Sicily produced the development of the Siculo–Calabrian Rift Zone (SCRZ). This zone is represented by a ≈ 370 km-long fault belt consisting of 10 to 50 km long distinct fault segments which extend both offshore and on land being also responsible of the crustal seismicity of this region. The geological and morphological observations indicate that the active normal faults of the SCRZ are characterized by throw-rates ranging from 0.7 to 3.1 mm/a. They accommodate an almost uniform horizontal extension-rate of about 3.0 mm/a along a WNW–ESE regional extension direction. Based on our field observations and following empirical relationships between magnitude and surface rupture length connections between large crustal earthquakes and distinct fault segments of the SCRZ have been also tentatively tested. Our data indicate moreover that the magnitudes (M) of the historical and instrumental earthquakes are consistent with the estimated values and that the geometry and kinematics of the fault segments and the related different crustal features of the SCRZ control the different seismic behaviours of adjacent portions of the active rift zone.  相似文献   

Multivariate analysis of contamination in the mining district of Linares (Jaén, Spain)     

J. Martínez Lpez  J. Llamas Borrajo  E. De Miguel García  J. Rey Arrans  Ma C. Hidalgo Estvez  A.J. Sez Castillo 《Applied Geochemistry》2008,23(8):2324-2336

Historically, a significant level of mining activity has taken place in the batholite-related metalogenic enclave of Linares (Jaén province, Spain), associated with Pb–Ag, Cu, Zn and Fe sulphides and Ba sulphate mineralization, though mining here has now been abandoned. Additionally, the area features a significant amount of urban, industrial and agricultural activities. These considerations, taken together, explain the need to assess the levels of concentration of trace elements and to determine their relationship with geogenic and anthropogenic factors. For geochemical characterisation of the soil, the region has been divided into 126 grid squares with an area of 1 km². For each grid square, 32 trace elements have been analysed. Elemental concentrations of Cu, Pb, Zn, As and Mn have been included in statistical analyses. According to the reference levels established by the Regional Government (Junta de Andalucía), soils in a large part of the study area require amendment applications. The comparison of the mean content for each grid square with the reference levels reveals a significant degree of contamination of the soil by Cu (719 mg kg⁻¹), Pb (22,964 mg kg⁻¹) and As (100 mg kg⁻¹) in those grid squares affected by metallurgic activities. By means of factor analysis, four scores have been identified which together account for 80% of the variance observed. The first score is highly correlated with the logarithms of the variables Fe, Th, La, Ti, Al, Na, K, Zr, Y, Nb, Be and Sc. It is a “natural” factor that indicates the type of soil matrix (fundamentally granites and, to a lesser degree, Triassic materials). The second score shows high correlation with the logarithms of the variables Mo, Cu, Pb, Zn, Ag, Co, Mn, As, Cd, Sb, Ba, W and Sn, and is the “metallization” factor related to the mineralization that has been exploited. The third score is mainly determined by the logarithms of the variables Sr, Ca and Mg. This is a “natural” factor that indicates a type of carbonate soil matrix (Miocene). Finally, the fourth factor groups the logarithms of the variables Ni, V and Cr, elements that are associated with the combustion of fossil fuels. Analysis of the patterns of each of the factors identified enabled achieving a global characterisation of the study area. Cluster analysis of the observations showed there to be five clusters relating to the grid squares, differentiated by lithologies and degrees of contamination. These clusters are used to determine the background of granite and to calculate the anomalous load.  相似文献   

Dolomite in caves: Recent dolomite formation in oxic, non-sulfate environments. Castañar Cave, Spain     

Ana M. Alonso-Zarza  Andrea Martín-Prez 《Sedimentary Geology》2008,205(3-4):160-164

Dolomite is a common mineral in the rock record but rare in recent superficial environments. Where it does occur, it is related to anoxic, sulfate-rich environments and microbial activity. The occurrence of some dolomite deposits in caves, however, indicates that dolomite formation is also possible in oxic, non-sulfate settings. Dolomite is forming at 17 °C and in oxic-vadose conditions on the host rocks and aragonite speleothems of the Castañar Cave, Cáceres, Spain. It appears as spheroids and dumbbells 50–300 μm in diameter that internally consist of micron-sized rhombic to rounded crystals. Initially this dolomite is Ca-rich, non-stoichiometric and poorly ordered. Mg-rich solutions allow the precipitation of metastable Mg-rich carbonates, such as huntite. This soon transforms into this Ca-rich dolomite, which later “ages” to form a more stoichiometric dolomite. These dolomites show similarities to those grown under anoxic, sulfate-rich conditions and their presence in caves provides a different setting that may contribute to the understanding of the “dolomite problem”, including their initial formation and later recrystallization processes.  相似文献   

Invited reply to the Comment on: “Geomorphological, paleontological and Sr/Sr isotope analyses on early Pleistocene paleoshorelines to define the uplift of Central Apennines (Italy)”     

Marco Mancini  Elisabetta D'Anastasio  Paolo Marco De Martini 《Quaternary Research》2008,69(1):165-167

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