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101.
D. González-Zeas S. Quiroga A. Iglesias L. Garrote 《Regional Environmental Change》2014,14(5):1983-1993
The effects of climate change on agriculture are often characterised by changes in the average productivity of crops; however, these indicators provide limited information regarding the risks associated with fluctuations in productivity resulting from future changes in climate variability that may also affect agriculture. In this context, this study evaluates the combined effects of the risks associated with anomalies reflected by changes in the mean crop yield and the variability of productivity in European agro-climatic regions under future climate change scenarios. The objective of this study is to evaluate adaptation needs and to identify regional effects that should be addressed with greater urgency in the light of the risks and opportunities that are identified. The results show differential effects on regional agriculture and highlight the importance of considering both regional average impacts and the variability in crop productivity in setting priorities for the adaptation and maintenance of rural incomes and agricultural insurance programmes. 相似文献
102.
Flavia Tromboni Lucia Bortolini José Antonio Morábito 《Environment, Development and Sustainability》2014,16(6):1317-1336
This study presents an integrated hydrologic–economic model as decision support system for groundwater use and incorporates uncertainties of climate change. The model was developed with the Vensim software (Ventana Systems) for system dynamic simulations. The software permitted the integration of economic variables along with hydrologic variables, in a unified format with the aim of evaluating the economic impacts of climate change on arid environments. To test the model, we applied it in one of the upper Tunuyán River sub-basin, located in the Mendoza Province (Argentina), where irrigation comes from groundwater. The model defines the best mix of crops and the total land use required to maximize the total river sub-basin monetary income, considering as a limit the amount of water that does not exceed the natural annual aquifer recharge. To estimate the impacts of climatic changes, four scenarios were compared: the business as usual (with the number of existing wells) in a dry year with a temperature increase of 4 °C; the business as usual in a wet year with an increase in temperature of 1.1 °C; an efficient use of wells in a dry year and a temperature increase of 4 °C and an efficient use of wells in a wet year with a temperature increase of 1.1 °C. Outputs calculated by the model were: land use per crop, total sub-basin net benefit, total sub-basin water extraction, water extraction limit depending on river discharge and total number of wells required to irrigate the entire area. Preliminary results showed that the number of existing wells exceeded the optimized number of wells required to sustainably irrigate the entire river sub-basin. Results indicated that in an average river discharge year, if wells were efficiently used, further rural development would be possible, until the limit of 350 million m3 of water extraction per year was reached (650 million m3 for a wet year and 180 million m3 for a dry year). The unified format and the low cost of the software license make the model a useful tool for Water Resources Management Institutions, particularly in developing countries. 相似文献
103.
Central and Eastern European countries are a hotspot area when analyzing the impacts of climate change on agricultural and environmental sectors. This paper conducts a socio-economic evaluation of climate risks on crop production in Hungary, using panel data models. The region has a special location in the Carpathian basin, where the spatial distribution of precipitation varies highly from humid conditions in the western part to semiarid conditions in eastern Hungary. Under current conditions, crop systems are mainly rainfed, and water licences are massively underexploited. However, water stress projected by climate change scenarios could completely change this situation. In the near future (2021–2050), most of the crops examined could have better climatic conditions, while at the end of the century (2071–2100), lower yields are expected. Adaptation strategies must be based on an integrated evaluation which links economic and climatic aspects, and since the results show important differences in the case of individual systems, it is clear that the response has to be crop and region specific. 相似文献
104.
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106.
Alejandra V. González Valeria Gómez-Silva María José Ramírez Francisco E. Fontúrbel 《Conservation biology》2020,34(3):711-720
Genetic diversity is a key factor for population survival and evolution. However, anthropogenic habitat disturbance can erode it, making populations more prone to extinction. Aiming to assess the global effects of habitat disturbance on plant genetic variation, we conducted a meta-analysis based on 92 case studies obtained from published literature. We compared the effects of habitat fragmentation and degradation on plant allelic richness and gene diversity (equivalent to expected heterozygosity) and tested whether such changes are sensitive to different life-forms, life spans, mating systems, and commonness. Anthropogenic disturbance had a negative effect on allelic richness, but not on gene diversity. Habitat fragmentation had a negative effect on genetic variation, whereas habitat degradation had no effect. When we examined the individual effects in fragmented habitats, allelic richness and gene diversity decreased, but this decrease was strongly dependent on certain plant traits. Specifically, common long-lived trees and self-incompatible species were more susceptible to allelic richness loss. Conversely, gene diversity decreased in common short-lived species (herbs) with self-compatible reproduction. In a wider geographical context, tropical plant communities were more sensitive to allelic richness loss, whereas temperate plant communities were more sensitive to gene diversity loss. Our synthesis showed complex responses to habitat disturbance among plant species. In many cases, the absence of effects could be the result of the time elapsed since the disturbance event or reproductive systems favoring self-pollination, but attention must be paid to those plant species that are more susceptible to losing genetic diversity, and appropriate conservation should be actions taken. 相似文献
107.
Victor E. Balderas-Hernández José T. Ornelas-Salas Ana P. Barba de la Rosa 《Journal of environmental science and health. Part. B》2020,55(2):148-154
AbstractThe presence of diethyl-phthalate (DEP), dibutyl-phthalate (DBP), butylbenzyl-phthalate (BBP), diethylhexyl-phthalate (DEHP) and diisononyl-phthalate (DINP) was determined in 295 tequila samples. They were grouped by age of maturation (white, aged, extra aged or ultra aged) and year of production (between 2013 and 2018). Gas Chromatography coupled with Mass Spectrometry was used for identification and quantification. The results showed that 65 samples (22% of the total) were phthalate free. DEP (0.13-0.27?mg/kg), BBP (0.05–2.91?mg/kg) and DINP (1.64–3.43?mg/kg) were detected in 11 (3.73%), 37 (12.54%) and 5 (1.69%) samples, respectively. But, these concentrations did not exceed the maximum permitted limits (MPL) of phthalates for alcoholic beverages. DBP (0.01–2.20?mg/kg) and DEHP (0.03–4.64?mg/kg) were detected in 96 (32.54%) and 224 (75.93%) samples, from them only 10 (3.39%) and 15 (5.08%) samples, respectively, exceeded the MPL for alcoholic beverages and they were few tequilas produced in the year 2014 or before. DEHP was the most frequent phthalate found in tequila and observed DEHP concentrations were 2-times higher in ultra aged tequilas compared to those in white tequilas. We concluded that all tequilas produced in 2015 and after, satisfied the international standards for these compounds. 相似文献
108.
García Hernández JE Notario del Pino JS González Martín MM Díaz Díaz R Febles González EJ 《Environmental pollution (Barking, Essex : 1987)》1995,88(3):355-359
The performance of phillipsite as a matrix for slow-release formulation of oxamyl [N,N-dimethyl-2-methylcarbamoyl-oxymino-2-(methylthio)acetamide] was tested. The adsorption kinetics followed a first-order law, and the adsorption isotherm fitted well in a two-surface Langmuir model, suggesting a double mechanism of interaction between oxamyl and the sorbent. The sorption mechanism, studied by FTIR, provided two fractions of oxamyl. The first one is sorbed on the mineral surface, linked by H-bonding, and the second one is constituted by a multilayer of oxamyl molecules linked by a water bridge between them. The release kinetics of oxamyl from a substratum zeolite-oxamyl also follows a first-order law, with two stages that correspond to both fractions of oxamyl previously detected. 相似文献
109.
González CM Casanovas SS Pignata ML 《Environmental pollution (Barking, Essex : 1987)》1996,91(3):269-277
The lichen Ramalina ecklonii (Spreng.) Mey. and Flot. was transplanted to 29 biomonitoring sites in the southeastern area of Córdoba, Argentina and tested for chlorophyll a, phaeophytin a, conjugated dienes concentration, malondialdehyde, soluble protein content and sulfur accumulation. The biomonitoring sites were determined according to (i) vehicular traffic levels, and (ii) industrial density, i.e. number and type of industries (small and medium) close to each of the sites. Each of the two groups were then broken down into three categories which provided a basis for performance analysis and quantification of the chemical parameters in the biomonitor. A pollution index (P.I.) was calculated based on the ratio of phaeophytin a to chlorophyll a and ratio of sulfur, malonaldehyde and conjugated dienes in transplanted specimens to sulfur, malonaldehyde and conjugated dienes in the freshly picked specimens. Significant differences were observed in sulfur content and P.I. in lichen samples that had been transplanted to sites with different vehicular traffic levels. At the same time, significant differences in the phaeophytin a concentration, phaeophytin a/chlorophyll a ratio and P.I. were observed at sites characterized by different levels of industrial density (all with low-to-medium traffic). 相似文献
110.
Ana B. Payá-Pérez Mohammed S. Rahman Helle Skejø-Andresen Bo R. Larsen 《Environmental science and pollution research international》1996,3(4):183-188
The soil/water partition coefficient (Kd) of hexachlorobenzene (HCB) ranged from 220 1/kg to 1800 1/kg for eight soils having a wide range of physico-chemical properties. Kd normalised to soil organic carbon (Koc) was found to be 28000 ± 4800 1/kg. Anionic surfactant dodecylsulphate (DS) present at concentrations above the critical micellar concentration (CMC) caused reductions in the apparent soil/water partition coefficient (Kd *) in the range of 3–26 times for most soils and up to 36–91 times for sandy soils. Below CMC, at environmentally relevant surfactant concentrations, Kd * was reduced by a factor of 1–13. For clay and calcareous soils significant adsorption/complexation/precipitation of DS occurred. At the lowest DS concentration this produced a two-fold increase in Kd *. At increasing DS concentrations this effect was shielded by the solubihzing effect from DS. Monomer (Kmn) and micellar (Kmc) surfactant/water partition coefficients for HCB were determined to be, 980 ± 190 1/kg and 21000 ± 1600 1/kg, respectively. 相似文献