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121.
Understanding the impacts of climate change on viticulture is especially essential in those areas producing high-quality wines. In this work, we create an operational framework to investigate climate change impact on viticulture in the Tuscany region (central Italy) the viticulture industry of which relies on producing high-quality wines to compete in a global market. The framework includes (i) statistical downscaling of General Circulation Model (GCM) outputs for the period 1975–2099 to a local scale; (ii) the use of downscaling outputs as driving variables in specific simulation models; (iii) the spatial interpolation of model outputs to feed an economic and (iv) a quality model. The results show that as a consequence of a progressive increase in temperature and a decrease in rainfall, (a) the area potentially suitable for grapevine cultivation increases; (b) the grapevine growth cycle becomes shorter; (c) the final yield is gradually reduced, particularly in those areas characterised by quality cultivation regulation; and d) the premium wine quality production areas shift towards higher elevations. The proposed framework revealed itself to be an effective tool for climate change impact assessment at a very local scale. Additionally, this approach may be easily extended to testing the effect of different adaptation strategies in terms of management practices (e.g. irrigation) and grape varieties (e.g. longer or shorter cycle, advanced or delayed bud burst).  相似文献   
122.
We have measured, in the edible frog (Pelophylax kl. esculentus), the effect of two fungicides (8-hydroxyquinoline and captan), and four herbicides (DCMU, glyphosate, paraquat, and propachlor) on the short-circuit current, whose value gives an estimate of the net ion transport taking place across isolated skin. Glyphosate and paraquat treatment produced a modest increase in short-circuit current, corresponding to 2.6±0.7 and 4.6±0.8 μA·cm?2, whereas the other substances had a more sustained effect, ranging from 9.1±0.6 (propachlor) to 14.8±0.9 μA·cm?2 (captan), which is mainly attributable to an increase in the Na+ absorption, and, to a lesser extent, Cl? secretion. The increase in short-circuit current after pesticide treatment, was partially abolished by AF12198, indomethacin, SC58125, SQ 22536, and W7; these results suggest that pesticides, independently from their chemical structure, induce the release of interleukin-1, which triggers the activity of cyclooxygenase-2, whose products, via a concentration in intracellular cAMP and Ca2+ concentration, increase Na+ absorption. The resulting Na+ disequilibrium must be compensated for by other epithelia, with the only consequence being the dissipation of energy. However, our results are important because they indicate that pesticides interact with the basic cellular machinery, which is responsible for the myriad of biological functions of different cell types.  相似文献   
123.
The effect of land application of biosolids on an agricultural soil was studied in a 2-month incubation experiment. The soil microbial biomass and the availability of heavy metals in the soil was monitored after the application of four different composting mixtures of sewage sludge and cotton waste, at different stages of composting. Land application caused an increase of both size and activity of soil microbial biomass that was related to the stabilization degree of the composting mixture. Sewage sludge stabilization through composting reduced the perturbance of the soil microbial biomass. At the end of the experiment, the size and the activity of the soil microbial biomass following the addition of untreated sewage sludge were twice those developed with mature compost. For the mature compost, the soil microbial biomass recovered its original equilibrium status (defined as the specific respiration activity, qCO2) after 18 days of incubation, whereas the soil amended with less stabilized materials did not recover equilibrium even after the two-month incubation period. The stabilization degree of the added materials did not affect the availability of Zn, Ni, Pb, Cu, Cr and Cd in the soil in the low heavy metal content of the sewage sludge studied. Stabilization of organic wastes before soil application is advisable for the lower perturbation of soil equilibria status and the more efficient C mineralization.  相似文献   
124.
125.
Silica gel surface has been modified in two reaction steps: (i) the silylating agent 3-mercaptopropyltrimetoxysilane was firstly immobilized to give a surface Sil-SH and (ii) this precursor incorporated an ethylene sulfide molecule to obtain the surface denoted Sil-SSH. This material was characterized by elemental analysis, IR spectroscopy, thermogravimetry, solid state 13C and 29Si NMR, and surface area measurement. These materials were employed as adsorbents for divalent heavy cations from aqueous solutions at room temperature and the isotherms were adjusted to a modified Langmuir equation. The maxima number of moles adsorbed were 1.0, 1.5, 1.6, 2.2, 2.4 and 3.3 mmol g(-1) for Co, Cu, Ni, Cd, Pb, and Hg, respectively.  相似文献   
126.
127.
Soil is a multifunctional, non-renewable natural resource for Europe as clearly expressed in the European Union (EU) Thematic Strategy for Soil Protection (COM (2006)231). Soil carries out multiple functions, including the support of food production. Urban development and its associated land take poses a major threat to soil and could have significant effects on agricultural production. This paper aims to evaluate the potential productivity losses in European agriculture due to land-take processes between 1990 and 2006. Agricultural land take was calculated using CORINE Land Cover maps of 1990, 2000 and 2006. For 21 of the 27 EU member states, agricultural land take was computed to be 752,973 ha for 1990–2000 and 436,095 ha for 2000–2006, representing 70.8% and 53.5%, respectively, of the total EU land take for these periods. The impact of this land take on the production capabilities of the agricultural sector for the period 1990–2006 for 19 of the 21 states was estimated to be equivalent to a loss of more than six million tonnes of wheat. The paper demonstrates that Europe's intense urbanisation has a direct impact on its capability to produce food.  相似文献   
128.
In the European Alps the increase in air temperature was more than twice the increase in global mean temperature over the last 50 years. The abiotic (glacial) and the biotic components (plants and vegetation) of the mountain environment are showing ample evidence of climate change impacts. In the Alps most small glaciers (80% of total glacial coverage and an important contribution to water resources) could disappear in the next decades. Recently climate change was demonstrated to affect higher levels of ecological systems, with vegetation exhibiting surface area changes, indicating that alpine and nival vegetation may be able to respond in a fast and flexible way in response to 1-2 degrees C warming. We analyzed the glacier evolution (terminus fluctuations, mass balances, surface area variations), local climate, and vegetation succession on the forefield of Sforzellina Glacier (Upper Valtellina, central Italian Alps) over the past three decades. We aimed to quantify the impacts of climate change on coupled biotic and abiotic components of high alpine ecosystems, to verify if an acceleration was occurring on them during the last decade (i.e., 1996-2006) and to assess whether new specific strategies were adopted for plant colonization and development. All the glaciological data indicate that a glacial retreat and shrinkage occurred and was much stronger after 2002 than during the last 35 years. Vegetation started to colonize surfaces deglaciated for only one year, with a rate at least four times greater than that reported in the literature for the establishment of scattered individuals and about two times greater for the well-established discontinuous early-successional community. The colonization strategy changed: the first colonizers are early-successional, scree slopes, and perennial clonal species with high phenotypic plasticity rather than pioneer and snowbed species. This impressive acceleration coincided with only slight local summer warming (approximately -0.5 degree C) and a poorly documented local decrease in the snow cover depth and duration. Are we facing accelerated ecological responses to climatic changes and/or did we go beyond a threshold over which major ecosystem changes may occur in response to even minor climatic variations?  相似文献   
129.
Two species of giant clams, Tridacna maxima and T. squamosa, coexist in the Red Sea, but exhibit distinctly different depth distributions: T. maxima mostly occurs in shallow waters (reef flat and edge), while T. squamosa may occur down to the lower fore-reef slope. Giant clams have been described as mixotrophic, capable of both filter-feeding and photosynthesis due to algal symbionts (zooxanthellae), therefore, observed depth preferences were investigated in relation to possible differences in autotrophy vs. heterotrophy. This study was conducted from April to June 2004, at the reef near the Marine Science Station, Aqaba, Gulf of Aqaba, Red Sea, and in May 2007, at a reef near Dahab, Sinai Peninsula, Egypt. In situ measurements using a submersible pulse amplitude modulated fluorometer (Diving PAM), revealed no significant differences in effective PSII quantum yield (ΔF/Fm′) and relative electron transport rates (ETR) between the two species; but rapid light curves (ETR vs. light, photosynthetically active irradiance, PAR) showed significant differences in maximum photosynthetic rates (ETRmax), with 20% higher values in T. maxima. Chamber incubations displayed higher net and gross oxygen production by T. maxima (88.0 and 120.3 μmol O2 cm−2 mantle area day−1) than T. squamosa (56.7 and 84.8 μmol O2 cm−2 mantle area day−1); even under shading conditions (simulated depth of 20 m) T. maxima still achieved 93% of the surface gross O2 production, whereas T. squamosa reached only 44%. A correlation was found between ETR and net photosynthesis measured as oxygen production (T. maxima: R 2 = 0.53; T. squamosa: R 2 = 0.61). Calculated compensation depth (CD) (gross photosynthesis equals respiration) in T. maxima (16 m) matches the maximum depth of occurrence in this study (17 m). By contrast, the CD of T. squamosa (9 m) was much shallower than the maximum vertical range (42 m). Findings suggest T. maxima is a strict functional photoautotroph limited by light, whereas T. squamosa is a mixotroph whose photoautotrophic range is extended by heterotrophy. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
130.
Environmental Science and Pollution Research - In the present work, silver nanoparticles (AgNPs) synthetized with Cryptocarya alba (Peumo) leaf extract were studied. The fabrication method was...  相似文献   
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