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1.
Mycorrhiza ; 33(5-6): 291-302, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37462722

RESUMO

The white truffle (Tuber magnatum Picco.; WT) is the most expensive and arguably also the most delicious species within the genus Tuber. Due to its hidden belowground life cycle, complex host symbiosis, and yet unknown distribution, cultivation of the enigmatic species has only recently been achieved at some plantations in France. A sustainable production of WTs under future climate change, however, requires a better ecological understanding of the species' natural occurrence. Here, we combine information from truffle hunters with a literature review to assess the climatic, edaphic, geographic, and symbiotic characteristics of 231 reported WT sites in southeast Europe. Our meta-study shows that 75% of the WT sites are located outside the species' most famous harvest region, the Piedmont in northern Italy. Spanning a wide geographic range from ~ 37° N in Sicily to ~ 47° N in Hungary, and elevations between sea level in the north and 1000 m asl in the south, all WT sites are characterised by mean winter temperatures > 0.4 °C and summer precipitation totals of ~ 50 mm. Often formed during past flood or landslide events, current soil conditions of the WT sites exhibit pH levels between 6.4 and 8.7, high macroporosity, and a cation exchange capacity of ~ 17 meq/100 g. At least 26 potential host species from 12 genera were reported at the WT sites, with Populus alba and Quercus cerris accounting for 23.5% of all plant species. We expect our findings to contribute to a sustainable WT industry under changing environmental and economic conditions.


Assuntos
Ascomicetos , Micorrizas , Simbiose , Solo
2.
Environ Manage ; 72(3): 631-656, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37289248

RESUMO

The impacts of climate change on people and ecosystems have been studied at both local and global levels. The environment is expected to change significantly, and the role of local communities in shaping more resilient landscapes is considered crucial. This research focuses on rural regions highly susceptible to climate change impacts. The objective was to enhance conditions for climate resilient development on a microlocal level by encouraging diverse stakeholders to participate in developing sustainable landscape management. This paper introduces a novel interdisciplinary mixed-method approach to landscape scenario development, combining research-driven and participatory approaches and integrating quantitative methods with qualitative ethnographic inquiry. Two scenarios for 2050 were built: a research-driven, business-as-usual scenario accounting for mandatory adaptation policies and an optimistic scenario combining research-driven and participatory approaches, including additional feasible community-based measures. While the differences between the projected land use seem to be relatively subtle, the optimistic scenario would in fact lead to a considerably more resilient landscape. The results highlight the role of interdisciplinarity and ethnography in gaining good local knowledge and building an atmosphere of trust. These factors supported the research credibility, strengthened the legitimacy of the intervention in local affairs, and contributed to the active participation of the stakeholders. We argue that despite its time, intense effort and limited direct policy impact, the mixed-method approach is highly suitable for the microlocal level. It encourages citizens to think about how their environment is threatened by climate change impacts and increases their willingness to contribute to climate resilience.


Assuntos
Mudança Climática , Ecossistema , Humanos
3.
Environ Manage ; 69(1): 128-139, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34453592

RESUMO

As ongoing research efforts contribute to elucidating the consequences of climate change as well as adaptation and mitigation options, aligning the current research knowledge with stakeholder opinions and perceptions remains critical for adopting effective climate change policies. This paper utilizes an interactive survey to (1) address the aforementioned gap in studies involving three groups of stakeholders and opinion makers and (2) perform a comparative primary study of the climate change assumptions, risk perceptions, policy preferences, observations, and knowledge of Czech farmers, governmental policy-makers and researchers. This study shows that the stakeholder groups agree that the climate is clearly changing, attribute this change mostly to man-made causes and expect the negative effects to either prevail or be unevenly geographically distributed. The large majority of all three groups consider unmitigated climate change a major threat even by 2050 and agree that preparing in advance is the best sectoral strategy. Importantly, while investment in adaptation measures is considered the most efficient tool for accelerating the implementation of adaptation measures, the CAP and EU rules (as valid in 2016) are believed to hinder such measures. The results of this study have ramifications for the wider region of Central Europe.


Assuntos
Mudança Climática , Agricultura Florestal , Agricultura/métodos , Consenso , República Tcheca , Humanos , Políticas
4.
Agric For Meteorol ; 282-283: 107862, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32184532

RESUMO

Winter wheat is an important crop in the UK, suited to the typical weather conditions in the current climate. In a changing climate the increased frequency and severity of adverse weather events, which are often localised, are considered a major threat to wheat production. In the present study we assessed a range of adverse weather conditions, which can significantly affect yield, under current and future climates based on adverse weather indices. We analysed changes in the frequency, magnitude and spatial patterns of 10 adverse weather indices, at 25 sites across the UK, using climate scenarios from the CMIP5 ensemble of global climate models (GCMs) and two greenhouse gas emissions (RCP4.5 and RCP8.5). The future UK climate is expected to remain favourable for wheat production, with most adverse weather indicators reducing in magnitude by the mid-21st century. Hotter and drier summers would improve sowing and harvesting conditions and reduce the risk of lodging. The probability of late frosts and heat stress during reproductive and grain filling periods would likely remain small in 2050. Wetter winter and spring could cause issues with waterlogging. The severity of drought stress during reproduction would generally be lower in 2050, however localised differences suggest it is important to examine drought at a small spatial scale. Prolonged water stress does not increase considerably in the UK, as may be expected in other parts of Europe. Climate projections based on the CMIP5 ensemble reveal considerable uncertainty in the magnitude of adverse weather conditions including waterlogging, drought and water stress. The variation in adverse weather conditions due to GCMs was generally greater than between emissions scenarios. Accordingly, CMIP5 ensembles should be used in the assessment of adverse weather conditions for crop production to indicate the full range of possible impacts, which a limited number of GCMs may not provide.

5.
Glob Chang Biol ; 24(8): 3780-3790, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29691942

RESUMO

Many organisms adjust their reproductive phenology in response to climate change, but phenological sensitivity to temperature may vary between species. For example, resident and migratory birds have vastly different annual cycles, which can cause differential temperature sensitivity at the breeding grounds, and may affect competitive dynamics. Currently, however, adjustment to climate change in resident and migratory birds have been studied separately or at relatively small geographical scales with varying time series durations and methodologies. Here, we studied differential effects of temperature on resident and migratory birds using the mean egg laying initiation dates from 10 European nest box schemes between 1991 and 2015 that had data on at least one resident tit species and at least one migratory flycatcher species. We found that both tits and flycatchers advanced laying in response to spring warming, but resident tit populations advanced more strongly in relation to temperature increases than migratory flycatchers. These different temperature responses have already led to a divergence in laying dates between tits and flycatchers of on average 0.94 days per decade over the current study period. Interestingly, this divergence was stronger at lower latitudes where the interval between tit and flycatcher phenology is smaller and winter conditions can be considered more favorable for resident birds. This could indicate that phenological adjustment to climate change by flycatchers is increasingly hampered by competition with resident species. Indeed, we found that tit laying date had an additional effect on flycatcher laying date after controlling for temperature, and this effect was strongest in areas with the shortest interval between both species groups. Combined, our results suggest that the differential effect of climate change on species groups with overlapping breeding ecology affects the phenological interval between them, potentially affecting interspecific interactions.


Assuntos
Migração Animal/fisiologia , Mudança Climática , Comportamento de Nidação/fisiologia , Passeriformes/fisiologia , Animais , Europa (Continente) , Passeriformes/classificação , Reprodução , Estações do Ano , Temperatura
6.
Int J Biometeorol ; 58(5): 809-17, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23640249

RESUMO

The phenological responses to climate of residents and migrants (short- and long-distance) differ. Although few previous studies have focussed on this topic, the agree that changes in phenology are more apparent for residents than for long-distance migrants. We analysed the breeding times of two selected residents (Sitta europaea, Parus major) and one long-distance migrant (Ficedula albicollis) from 1961 to 2007 in central Europe. The timing of the phenophases of all three bird species showed a significant advance to earlier times. Nevertheless, the most marked shift was observed for the long-distance migrant (1.9 days per decade on average in mean laying date with linearity at the 99.9% confidence level). In contrast, the shifts shown by the residents were smaller (1.6 days for S. europaea and 1.5 days for P. major also on average in mean laying date for both, with linearity at the 95% confidence level). Spearman rank correlation coefficients calculated for pairs of phenophases of given bird species in 20-year subsamples (e.g. 1961-1980, 1962-1981) showed higher phenological separation between the residents and the migrant. This separation is most apparent after the 1980s. Thus, our results indicate that the interconnections between the studied phenological stages of the three bird species are becoming weaker.


Assuntos
Passeriformes/fisiologia , Reprodução , Migração Animal , Animais , Europa (Continente) , Estações do Ano , Temperatura
7.
Sci Total Environ ; 921: 171173, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38401718

RESUMO

The efficiency of water use in plants, a critical ecophysiological parameter closely related to water and carbon cycles, is essential for understanding the interactions between plants and their environment. This study investigates the effects of ongoing climate change and increasing atmospheric CO2 concentration on intrinsic (stomata-based; iWUE) and evaporative (transpiration-based; eWUE) water use efficiency in oak trees along a naturally small altitudinal gradient (130-630 m a.s.l.) of Vihorlat Mountains (eastern Slovakia, Central Europe). To assess changes in iWUE and eWUE values over the past 60 years (1961-2020), stable carbon isotope ratios in latewood cellulose (δ13Ccell) of annually resolved tree rings were analyzed. Such an approach was sensitive enough to distinguish tree responses to growth environments at different altitudes. Our findings revealed a rising trend in iWUE, particularly in oak trees at low and middle altitudes. However, this increase was negligible at high altitudes. Warmer and drier conditions at lower altitudes likely led to significant stomatal closure and enhanced efficiency in photosynthetic CO2 uptake due to rising CO2 concentration. Conversely, the increasing intracellular-to-ambient CO2 ratio (Ci/Ca) at higher altitudes indicated lower efficiency in photosynthetic CO2 uptake. In contrast to iWUE, eWUE showed no increasing trends over the last 60 years. This suggests that the positive impacts of elevated CO2 concentrations and temperature on photosynthesis and stomatal closure are counteracted by the rising atmospheric vapor pressure deficit (VPD). These differences underscore the importance of the correct interpretation of stomata-based and transpiration-based WUEs and highlight the necessity of atmospheric VPD correction when applying tree-ring δ13C-derived WUE at ecosystem and global levels.


Assuntos
Dióxido de Carbono , Ecossistema , Dióxido de Carbono/farmacologia , Temperatura , Pressão de Vapor , Gases , Fotossíntese , Isótopos de Carbono/análise , Água
8.
PLoS One ; 18(3): e0256976, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36888624

RESUMO

The forests of central Europe have undergone remarkable transitions in the past 40 years as air quality has improved dramatically. Retrospective analysis of Norway spruce (Picea abies) tree rings in the Czech Republic shows that air pollution (e.g. SO2 concentrations, high acidic deposition to the forest canopy) plays a dominant role in driving forest health. Extensive soil acidification occurred in the highly polluted "Black Triangle" in Central Europe, and upper mineral soils are still acidified. In contrast, acidic atmospheric deposition declined by 80% and atmospheric SO2 concentration by 90% between the late 1980s and 2010s. In this study we oserved that annual tree ring width (TRW) declined in the 1970s and subsequently recovered in the 1990s, tracking SO2 concentrations closely. Furthermore, recovery of TRW was similar in unlimed and limed stands. Despite large increases in soil base saturation, as well as soil pH, as a result of repeated liming starting in 1981, TRW growth was similar in limed and unlimed plots. TRW recovery was interrupted in 1996 when highly acidic rime (originating from more pronounced decline of alkaline dust than SO2 from local power plants) injured the spruce canopy, but recovered soon to the pre-episode growth. Across the long-term site history, changes in soil chemistry (pH, base saturation, Bc/Al soil solution ratio) cannot explain observed changes in TRW at the two study sites where we tracked soil chemistry. Instead, statistically significant recovery in TRW is linked to the trajectory of annual SO2 concentrations or sulfur deposition at all three stands.


Assuntos
Poluição do Ar , Picea , Solo , Estudos Retrospectivos , Florestas , Concentração de Íons de Hidrogênio
9.
Plant Physiol Biochem ; 205: 108155, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37952365

RESUMO

Minimizing the impact of heat and drought on crop yields requires varieties with effective protective mechanisms. We tested the hypothesis that even a short-term high temperature amplifies the negative effects of reduced water availability on leaf gas-exchange, but can induce long-lasting improvement in plant water-use efficiency after the stress period. Accordingly, three common varieties of winter wheat (Triticum aestivum) were grown under field conditions. During the stem extension, the plants were exposed to distinct temperatures (daily maximum 26 vs. 38 °C), water availabilities (75% of field water capacity vs. permanent wilting point), and their combination for 14 days. All treatments reduced light-saturated rates of CO2 assimilation and transpiration, particularly when heat and drought were combined. Drought enhanced water-use efficiency (WUE) in all varieties (31.4-36.4%), but not at high temperatures (decrease by 17-52%). Intrinsic WUE (iWUE), determined from the stable carbon isotope composition of grains, was enhanced by 7.9-37% in all treatments and varieties; however, not all changes were significant. The combination of heat and drought tended to increase total protein content in grains but reduced spike productivity. Noticeably, the strongest decline in spike productivity was observed in Elan - the variety displaying the smallest enhancement of iWUE, while it was negligible in Pannonia which shows the most pronounced improvement of iWUE. We conclude that even several hot and dry days can improve iWUE for the rest of the vegetation season. This improvement, however, does not necessarily lead to increased crop productivity possibly due to physiological trade-offs.


Assuntos
Triticum , Água , Água/metabolismo , Triticum/metabolismo , Temperatura , Isótopos de Carbono , Secas , Grão Comestível/metabolismo
10.
Nat Commun ; 14(1): 6028, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816707

RESUMO

A recent rise in the global brewery sector has increased the demand for high-quality, late summer hops. The effects of ongoing and predicted climate change on the yield and aroma of hops, however, remain largely unknown. Here, we combine meteorological measurements and model projections to assess the climate sensitivity of the yield, alpha content and cone development of European hops between 1970 and 2050 CE, when temperature increases by 1.4 °C and precipitation decreases by 24 mm. Accounting for almost 90% of all hop-growing regions, our results from Germany, the Czech Republic and Slovenia show that hop ripening started approximately 20 days earlier, production declined by almost 0.2 t/ha/year, and the alpha content decreased by circa 0.6% when comparing data before and after 1994 CE. A predicted decline in hop yield and alpha content of 4-18% and 20-31% by 2050 CE, respectively, calls for immediate adaptation measures to stabilize an ever-growing global sector.


Assuntos
Humulus , Mudança Climática , Agricultura/métodos , Temperatura , Odorantes
11.
J Hydrol Reg Stud ; 50: 101534, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38145056

RESUMO

Study region: The Morava River basin, Czech Republic, Danube Basin, Central Europe. Study focus: Hydrological summer extremes represent a prominent natural hazard in Central Europe. River low flows constrain transport and water supply for agriculture, industry and society, and flood events are known to cause material damage and human loss. However, understanding changes in the frequency and magnitude of hydrological extremes is associated with great uncertainty due to the limited number of gauge observations. Here, we compile a tree-ring network to reconstruct the July-September baseflow variability of the Morava River from 1745 to 2018 CE. An ensemble of reconstructions was produced to assess the impact of calibration period length and trend on the long-term mean of reconstruction estimates. The final estimates represent the first baseflow reconstruction based on tree rings from the European continent. Simulated flows and historical documentation provide quantitative and qualitative validation of estimates prior to the 20th century. New hydrological insights for the region: The reconstructions indicate an increased variability of warm-season flow during the past 100 years, with the most extreme high and low flows occurring after the start of instrumental observations. When analyzing the entire reconstruction, the negative trend in baseflow displayed by gauges across the basin after 1960 is not unprecedented. We conjecture that even lower flows could likely occur in the future considering that pre-instrumental trends were not primarily driven by rising temperature (and the evaporative demand) in contrast to the recent trends.

12.
Environ Pollut ; 304: 119104, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35301033

RESUMO

Tree rings provide valuable insight into past environmental changes. This study aimed to evaluate perturbations in tree ring width (TRW) and δ15N alongside soil acidity and nutrient availability gradients caused by the contrasting legacy of air pollution (nitrogen [N] and sulphur [S] deposition) and tree species (European beech, Silver fir and Norway spruce). We found consistent declines of tree ring δ15N, which were temporarily unrelated to the changes in the TRW. The rate of δ15N change in tree rings was related to the contemporary foliar carbon (C) to phosphorus (P) ratio. This observation suggested that the long-term accumulation of 15N depleted N in tree rings, likely mediated by retained N from deposition, was restricted primarily to stands with currently higher P availability. The shifts observed in tree-ring δ15N and TRW suggest that acidic air pollution rather than changes in stand productivity determined alteration of N and C cycles. Stable N isotopes in tree rings provided helpful information on the trajectory of the N cycle over the last century with direct consequences for a better understanding of future interactions among N, P and C cycles in terrestrial ecosystems.


Assuntos
Fagus , Picea , Isótopos de Carbono/análise , Ecossistema , Florestas , Nitrogênio , Isótopos de Nitrogênio/análise
13.
Int J Biometeorol ; 54(1): 99-111, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20099374

RESUMO

This study is based on 47 years of observations (1961-2007) on two common bird species, the Great Tit (Parus major) and the Collared Flycatcher (Ficedula albicollis), and a dominant tree species in their habitat, the English Oak (Quercus robur). The study took place at four research sites in the Czech Republic located in full-grown, multi-aged floodplain forests with no forestry management. An increase in air temperature over the evaluated period clearly influenced the length of phenological phases. The full foliage date of English Oak has advanced by 8.7 days during the past 47 years. Great Tit and Collared Flycatcher populations have reacted to the changing climate in the same way, with first laying date and mean laying date advancing by between 6.0 and 9.0 days. In all cases, the trends are highly significant and consistent over all sites. Despite the ongoing shift in phenological stages toward the beginning of the year, the change does not appear to have led to mistiming in the trophic food chain. Overall, this study shows almost identical rates of change in egg laying dates for both bird species in all the floodplain forests studied, and these trends are coherent with those of English Oak and peak herbivorous caterpillar activity.


Assuntos
Migração Animal/fisiologia , Aves/fisiologia , Mudança Climática/estatística & dados numéricos , Ecossistema , Dinâmica Populacional , Comportamento Sexual Animal/fisiologia , Árvores , Animais , Simulação por Computador , República Tcheca , Modelos Estatísticos , Temperatura
14.
Sci Rep ; 10(1): 21281, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33277535

RESUMO

Climate change affects the distribution of many species, including Burgundy and Périgord truffles in central and southern Europe, respectively. The cultivation potential of these high-prized cash crops under future warming, however, remains highly uncertain. Here we perform a literature review to define the ecological requirements for the growth of both truffle species. This information is used to develop niche models, and to estimate their cultivation potential in the Czech Republic under current (2020) and future (2050) climate conditions. The Burgundy truffle is already highly suitable for cultivation on ~ 14% of agricultural land in the Czech Republic (8486 km2), whereas only ~ 8% of the warmest part of southern Moravia are currently characterised by a low suitability for Périgord truffles (6418 km2). Though rising temperatures under RCP8.5 will reduce the highly suitable cultivation areas by 7%, the 250 km2 (3%) expansion under low-emission scenarios will stimulate Burgundy truffles to benefit from future warming. Doubling the moderate and expanding the highly suitable land by 352 km2 in 2050, the overall cultivation potential for Périgord truffles will rise substantially. Our findings suggest that Burgundy and Périgord truffles could become important high-value crops for many regions in central Europe with alkaline soils. Although associated with uncertainty, long-term investments in truffle cultivation could generate a wide range of ecological and economic benefits.

15.
Sci Total Environ ; 658: 1186-1208, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30677982

RESUMO

The impact of climate change could undermine the future grain production as a consequence of increased temperature and drought condition or improve the crop performance owing to the increased CO2 in the atmosphere. Wheat water demand and yield are strictly related to climate conditions of the area where the plants are cropped. In this study, we assessed the future trends of grain yield and water consumption in two European regions, Germany (Continental region) and Italy (Mediterranean region) in the light of the multiple sources of uncertainty related to climate and yield forecasts. Four crop models were set up under combinations of two European climate regions, five Global Circulation Models and two Representative CO2 Concentration Pathways, 486 ppm and 540 ppm in 2050. Yield and water use were assessed under rainfed and irrigated regimes, and the water footprint of green water and total water was estimated. Our results indicated that projected yields were comparable (Mediterranean area) or even improved (+9%; Continental area) in rainfed conditions in comparison to the current trend; and water supply enhanced crop performance (+22% in Germany and +19% in Italy, as mean). Crop water consumption (both green and blue) remained stable in future projections but the water footprint was 5% lower on average in Italy and 23% in Germany when compared to the baseline. Despite the uncertainty in future predictions related to the factors analysed, our result indicated that current wheat production and its water footprint could become more favourable under climate change.


Assuntos
Mudança Climática , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Água/metabolismo , Secas , Alemanha , Itália , Modelos Biológicos , Incerteza
16.
Sci Adv ; 5(9): eaau2406, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31579815

RESUMO

Global warming is expected to increase the frequency and intensity of severe water scarcity (SWS) events, which negatively affect rain-fed crops such as wheat, a key source of calories and protein for humans. Here, we develop a method to simultaneously quantify SWS over the world's entire wheat-growing area and calculate the probabilities of multiple/sequential SWS events for baseline and future climates. Our projections show that, without climate change mitigation (representative concentration pathway 8.5), up to 60% of the current wheat-growing area will face simultaneous SWS events by the end of this century, compared to 15% today. Climate change stabilization in line with the Paris Agreement would substantially reduce the negative effects, but they would still double between 2041 and 2070 compared to current conditions. Future assessments of production shocks in food security should explicitly include the risk of severe, prolonged, and near-simultaneous droughts across key world wheat-producing areas.


Assuntos
Mudança Climática , Produtos Agrícolas , Modelos Teóricos , Triticum , Água , Abastecimento de Alimentos , Geografia , Aquecimento Global , Humanos , Estações do Ano
17.
Sensors (Basel) ; 7(10): 2330-2362, 2007 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-28903230

RESUMO

The results of previous studies have suggested that estimated daily globalradiation (RG) values contain an error that could compromise the precision of subsequentcrop model applications. The following study presents a detailed site and spatial analysis ofthe RG error propagation in CERES and WOFOST crop growth models in Central Europeanclimate conditions. The research was conducted i) at the eight individual sites in Austria andthe Czech Republic where measured daily RG values were available as a reference, withseven methods for RG estimation being tested, and ii) for the agricultural areas of the CzechRepublic using daily data from 52 weather stations, with five RG estimation methods. In thelatter case the RG values estimated from the hours of sunshine using the ångström-Prescottformula were used as the standard method because of the lack of measured RG data. At thesite level we found that even the use of methods based on hours of sunshine, which showedthe lowest bias in RG estimates, led to a significant distortion of the key crop model outputs.When the ångström-Prescott method was used to estimate RG, for example, deviationsgreater than ±10 per cent in winter wheat and spring barley yields were noted in 5 to 6 percent of cases. The precision of the yield estimates and other crop model outputs was lowerwhen RG estimates based on the diurnal temperature range and cloud cover were used (mean bias error 2.0 to 4.1 per cent). The methods for estimating RG from the diurnal temperature range produced a wheat yield bias of more than 25 per cent in 12 to 16 per cent of the seasons. Such uncertainty in the crop model outputs makes the reliability of any seasonal yield forecasts or climate change impact assessments questionable if they are based on this type of data. The spatial assessment of the RG data uncertainty propagation over the winter wheat yields also revealed significant differences within the study area. We found that RG estimates based on diurnal temperature range or its combination with daily total precipitation produced a bias of to 30 per cent in the mean winter wheat grain yields in some regions compared with simulations in which RG values had been estimated using the ångström-Prescott formula. In contrast to the results at the individual sites, the methods based on the diurnal temperature range in combination with daily precipitation totals showed significantly poorer performance than the methods based on the diurnal temperature range only. This was due to the marked increase in the bias in RG estimates with altitude, longitude or latitude of given region. These findings in our view should act as an incentive for further research to develop more precise and generally applicable methods for estimating daily RG based more on the underlying physical principles and/or the remote sensing approach.

18.
J R Soc Interface ; 12(112)2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26577595

RESUMO

Ways of increasing the production of wheat, the most widely grown cereal crop, will need to be found to meet the increasing demand caused by human population growth in the coming decades. This increase must occur despite the decrease in yield gains now being reported in some regions, increased price volatility and the expected increase in the frequency of adverse weather events that can reduce yields. However, if and how the frequency of adverse weather events will change over Europe, the most important wheat-growing area, has not yet been analysed. Here, we show that the accumulated probability of 11 adverse weather events with the potential to significantly reduce yield will increase markedly across all of Europe. We found that by the end of the century, the exposure of the key European wheat-growing areas, where most wheat production is currently concentrated, may increase more than twofold. However, if we consider the entire arable land area of Europe, a greater than threefold increase in risk was predicted. Therefore, shifting wheat production to new producing regions to reduce the risk might not be possible as the risk of adverse events beyond the key wheat-growing areas increases even more. Furthermore, we found a marked increase in wheat exposure to high temperatures, severe droughts and field inaccessibility compared with other types of adverse events. Our results also showed the limitations of some of the presently debated adaptation options and demonstrated the need for development of region-specific strategies. Other regions of the world could be affected by adverse weather events in the future in a way different from that considered here for Europe. This observation emphasizes the importance of conducting similar analyses for other major wheat regions.


Assuntos
Aclimatação , Mudança Climática , Produção Agrícola , Triticum/crescimento & desenvolvimento , Europa (Continente) , Humanos
19.
Sci Total Environ ; 538: 703-11, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26327638

RESUMO

Norway spruce (Picea abies (L.) Karst.) stands in certain areas of Central Europe have experienced substantial dieback since the 1970s. Understanding the reasons for this decline and reexamining the response of forests to acid deposition reduction remains challenging because of a lack of long and well-replicated tree-ring width chronologies. Here, spruce from a subalpine area heavily affected by acid deposition (from both sulfur and nitrogen compounds) is evaluated. Tree-ring width measurements from 98 trees between 1000 and 1350m above sea level (a.s.l.) reflected significant May-July temperature signals. Since the 1970s, acid deposition has reduced the growth-climate relationship. Efficient pollution control together with a warmer but not drier climate most likely caused the increased growth of spruce stands in this region, the so-called "Black Triangle," in the 1990s.


Assuntos
Chuva Ácida , Poluição do Ar/análise , Monitoramento Ambiental , Picea/crescimento & desenvolvimento , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Tchecoslováquia , Nitrogênio/análise , Polônia , Enxofre/análise
20.
Pest Manag Sci ; 70(5): 708-15, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23901033

RESUMO

BACKGROUND: This study aimed to estimate the impact of climate change on the ranges of crop pest species in Europe. The organisms included in the study were species from the family Tortricidae (Cydia pomonella, Lobesia botrana) and the family Pyralidae (Ostrinia nubilalis), Chrysomelidae beetles (Leptinotarsa decemlineata, Oulema melanopus) and species from the family Aphididae (Ropalosiphum padi, Sitobion avenae). Climate conditions in the year 2055 were simulated using a subset of five representative global circulation models. Model simulations using these climate change scenarios showed significant shifts in the climatic niches of the species in this study. RESULTS: For Central Europe, the models predicted a shift in the ranges of pest species to higher altitudes and increases in the number of generations (NG) of the pests. In contrast, in the southern regions of Europe, the NG is likely to decrease owing to insufficient humidity. The ranges of species are likely to shift to the north. CONCLUSION: Based on the ensemble-scenario mean for 2055, a climate-driven northward shift of between 3° N (O. nubilalis) and 11° N (L. botrana) is expected. The areas that are most sensitive to experiencing a significant increase in climate suitability for future pest persistence were identified. These areas include Central Europe, the higher altitudes of the Alps and Carpathians and areas above 55° N.


Assuntos
Afídeos/fisiologia , Mudança Climática , Besouros/fisiologia , Modelos Teóricos , Mariposas/fisiologia , Animais , Meio Ambiente , Europa (Continente) , Geografia , Especificidade da Espécie
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