With abundant evidence of recent climate warming, most vegetation studies have concentrated on its direct impacts, such as modifications to seasonal plant and animal life cycle events (phenology). The most common examples are indications of earlier onset of spring plant growth and delayed onset of autumn senescence. However, less attention has been paid to the implications of continued warming for plant species' chilling requirements. Many woody plants that grow in temperate areas require a certain amount of winter chilling to break dormancy and prepare to respond to springtime warming.
Thus, a comprehensive assessment of plant species' responses to warming must also include the potential impacts of insufficient chilling. When collected at continental scale, plant species phenological data can be used to extract information relating to the combined impacts of warming and reduced chilling on plant species physiology. In this brief study, we demonstrate that common lilac first leaf and first bloom phenology (collected from multiple locations in the western United States and matched with air temperature records) can estimate the species' chilling requirement (1748 chilling hours, base 7.2 °C) and highlight the changing impact of warming on the plant's phenological response in light of that requirement.
Specifically, when chilling is above the requirement, lilac first leaf/first bloom dates advance at a rate of − 5.0/− 4.2 days per 100-h reduction in chilling accumulation, while when chilling is below the requirement, they advance at a much reduced rate of − 1.6/− 2.2 days per 100-h reduction. With continental-scale phenology data being collected by the USA National Phenology Network (http://www.usanpn.org), these and more complex ecological questions related to warming and chilling can be addressed for other plant species in future studies.
Carbon in forest biomass has historically been the fulcrum for major changes in forestry and forests. Following T.S. Kuhn, these breaks with the past are seen as paradigm changes. We perceive planned adaptation of forestry and forests under climate change as a new paradigm change, precipitated once more by forest carbon. To be sustainable, forest management and conservation must embrace planned adaptation to and mitigation of mitigation of and adaptation to climate change. The current initiative of Reducing Emissions from Deforestation in Developing Countries (REDD) represents, beyond its original mitigation goal, a major facet of planned adaptation of forests and adjoining sectors in developing countries.
The initiative is gaining a powerful momentum for enhancing sustainable forest management in developing countries. REDD may also adapt relations between developing and developed countries in another paradigm change. Worldwide observations of climate change impacts on forests and IPCC forecasts project an image of forests and forestry entering a new era. Dealing with this future by relying on autonomous adaptation is unlikely to suffice.
Climate change will alter site and ecological conditions, increase risk in many forests, create new gaps in knowledge, increase the value of forest carbon and wood energy, and expand the international and human dimensions of forestry. Ending the proverbial seed dormancy of new developments in forestry, change is underway and appears expedient. We conclude that anticipatory planned adaptation of all facets of forestry to climate change imposes mitigation and adaptation as new boundary conditions for sustainable forest management and conservation, and amounts to a paradigm change.
Over the next decades mankind will demand more food from fewer land and water resources. This study quantifies the food production impacts of four alternative development scenarios from the Millennium Ecosystem Assessment and the Special Report on Emission Scenarios. Partially and jointly considered are land and water supply impacts from population growth, and technical change, as well as forest and agricultural commodity demand shifts from population growth and economic development. The income impacts on food demand are computed with dynamic elasticities.
Simulations with a global, partial equilibrium model of the agricultural and forest sectors show that per capita food levels increase in all examined development scenarios with minor impacts on food prices. Global agricultural land increases by up to 14% between 2010 and 2030. Deforestation restrictions strongly impact the price of land and water resources but have little consequences for the global level of food production and food prices. While projected income changes have the highest partial impact on per capita food consumption levels, population growth leads to the highest increase in total food production. The impact of technical change is amplified or mitigated by adaptations of land management intensities.
We present for the first time a study on alternative forest management at the European scale to account for climate change impacts. We combine insights into detailed studies at high resolution with the actual status of the forest and a realistic estimate of the current management practices at large scale. Results show that the European forest system is very inert and that it takes a long time to influence the species distribution by replacing species after final felling. By 2070, on average about 36 % of the area expected to have decreased species suitability will have changed species following business as usual management.
Alternative management, consisting of shorter rotations for those species and species planting based on expected trends, will have increased this species transition to 40 %. The simulated forward-looking alternative management leads to some reduction in increment, but does not influ- ence the amount of wood removed from the forest. Northern Europe is projected to show the highest produc- tion increases under climate change and can also adapt faster to the new (proposed) species distribution. Southwest Europe is expected to face the greatest challenge by a combination of a predicted loss of production and a slow rate of management alteration under climate change.
Risks can generally be described as the combination of hazard, exposure and vulnerability. Using this framework, we evaluated the historical and future development of risk of fire and wind damage in European forestry at the national level. Fire risk is expected to increase, mainly as a consequence of an increase in fire hazard, defined as the Fire Weather Index in summer. Exposure, defined as forest area, is expected to increase slightly as a consequence of active afforestation and abandonment of marginal agricultural areas.
Adaptation options to fire risk should therefore aim to decrease the vulnerability, where a change in tree species from conifers to broadleaves had most effect. Risk for wind damage in forests is expected to increase mainly as a consequence of increase in exposure (total growing stock) and vulnerability (defined by age class and tree species distribution). Projections of future wind climate indicate an increase in hazard (storminess) mainly over Western Europe.
Adaptation options should aim to limit the increase in exposure and vulnerability. Only an increase in harvest level can stop the current build-up of growing stock, while at the same time it will lower vulnerability through the reduction of the share of old and vulnerable stands. Changing species from conifers to broadleaves helps to reduce vulnerability as well. Lowering vulnerability by decreasing the rotation length is only effective in combination with a high demand for wood. Due to data limitations, no forecast of future fire area or damaged timber amount by storms was possible.
Biodiversity hotspots are among some of the habitats most threatened by climate change, and the Brazilian Atlantic forest is no exception. Only 11.6 % of the natural vegetation cover remains in an intensely fragmented state, which results in high vulnerability of this biome to climate change. Since > 60 % of the Brazilian people live within the Atlantic forest domain, societies both in rural and urban areas are also highly vulnerable to climate change.
This review examines the vulnerabilities of biodiversity and society in the Atlantic forest to climate change, as well as impacts of land use and climate change, particularly on recent biological evidence of strong synergies and feedback between them. We then discuss the crucial role ecosystem-based adaptation to climate change might play in increasing the resilience of local society to future climate scenarios and provide some ongoing examples of good adaptive practices, especially related to ecosystem restoration and conservation incentive schemes such as payment for ecosystem services.
Finally, we list a set of arguments about why we trust that the Atlantic forest can turn from a ‘‘shrinking biodiversity hotspot’’ to a climate adaptation ‘‘hope spot’’ whereby society’s vulnerability to climate change is reduced by protecting and restoring nature and improving human life standards.
To evaluate the vulnerability of agriculture under Mediterranean conditions, the real water needs of agriculture in the Fluvià watershed (Catalonia, NE Spain) were estimated for the XXIst century using a combination of downscaled climate projections (ECHAM5 plus MM5) in two IPCC scenarios (B1 and A2), watershed hydrological model (SWAT) and FAO procedure to calculate crop potential evapotranspiration. In comparison with baseline conditions (1984-2008), climate projections predicted a 12% (B1) to 28% (A2) reduction in precipitation, and a 2.2°C (B1) to 3.6°C (A2) increment of mean annual temperature at the end of the XXI Century (2076-2100).
The changes of the environmental conditions would affect the real water availability in different crops: water required for irrigation would increase significantly along the century, ranging from 40 to 250% depending on the crop, because of a direct decrease in the amount of water available along the growing season and because of the effects of the projected climatic conditions on potential evapotranspiration (ETO) and on the phenology of these crops. Results are showing the high sensitivity of agriculture, despite its expanding technology, to changes in climate, and even more to site, plot, orchard or terroir conditions.
Riparian ecosystems have unique biodiversity, are highly sensitive to disturbance and anthropogenic influence. As world water resources become scarcer, scientists predict greater competition among species for water resources. Indeed, increased encroachment of upland plants into the riparian zone is already occurring, irreversibly changing riparian plant communities. Since semi-arid regions such as Mediterranean-type ecosystems are likely to follow this same trajectory, assessing the contributions of riparian versus upland (sclerophyllous) plants to community composition is important. A survey of seventy 2 km-long riparian transects on the Sado and Guadiana watersheds in southern Portugal assessed (1) the woody riparian plant community composition, (2) how much richness is due to strictly riparian plants versus sclerophyllous upland plants, and (3) which combinations of biotic and abiotic factors allow higher species richness in the strictly riparian, sclerophyllous, and overall plant communities.
The survey detected 53 different woody plant species (28 endemic) across all communities. Riparian community richness was on average 16 species, seven of which were strictly riparian and the remainder being sclerophyllous, exotic species or fruit trees. Sclerophyllous plant species occurred consistently across sampling units (90% of transects). On average, 46% of the total woody plant community richness was due to strictly riparian plants and 28% was due to sclerophyllous plants. Community richness was positively affected by the area of shrubs in the riparian zone and by the absence of human activities and goats. Surrounding landscape pattern only affected the strictly riparian plant richness.
These results suggest that natural and human-mediated disturbances in riparian ecosystems create gaps and clearings for which riparian and sclerophyllous plants compete. Establishment success seems to be related to the propagule pressure of the neighbouring landscape, its diversity and density, as well as the presence of herbivores. Preserving strictly riparian plants, removing exotic species, preventing grazing, and promoting riparian values (recreation, aesthetics and the provision of ecosystem services) will aid the future conservation of the unique biodiversity of riparian ecosystems.
The main aim of this manuscript is to provide some fundamental concepts related to climate and to its inherent variability, which might be considered an essential tool for a better judgment of the large amounts of information currently available regarding this topic. This is particularly pertinent for agricultural research, as agronomic systems, including horticultural crops, tend to be largely regulated by climate and by atmospheric parameters.
Some elementary concepts on the nature of the climate system are first presented. Its components and coupling processes are succinctly described, giving particular emphasis to the spatial and temporal time scales relevant for agro-systems research. Both internal and forced climate variability are discussed from a physically-based perspective with a special focus on the anthropogenic forcing of the climate system. The discussion of these topics is followed by some essential ideas on atmospheric modeling. The need for the development of downscaling strategies is also underlined.
A categorization of the different climate system models and their application to agro-system research are thus discussed. The role of greenhouse gases in the radiation and energetic budget of the Earth's system are examined. In this respect, some relevant results of the last IPCC report concerning human-driven forcing mechanisms are also presented. Lastly, the likely impacts of a changing climate on several agronomic sectors are briefly covered.
The tomato red spider mite, Tetranychus evansi, is an emerging pest of solanaceous crops. Two distinct genetic lineages (I and II) have been identified, lineage I having a much wider geographic distribution than lineage II. This has been attributed to differences in cold hardiness that make lineage I better adapted to colonize the coldest parts of the invaded area. However, other factors such as the ability to exploit different hosts may also be involved. In this work, we compared the performance of the Nice (lineage I) and Perpignan (lineage II) strains of T. evansi on two frequent host plants for this species: black nightshade, Solanum nigrum, and cultivated tomato, S. lycopersicum.
In general, Nice strain mites performed better (higher fecundity, lower offspring mortality, bigger egg size and lower percentage of males) than Perpignan strain mites when both: (1) they were reared and tested on the same host plant (S. lycopersicum or S. nigrum); and (2) when shifted from S. nigrum to S. lycopersicum and vice versa. Digestive proteases showed also higher expression in Nice strain mites than in Perpignan strain mites, independently of their plant host, potentially reflecting a more efficient proteolytic digestion of plant proteins.
However, no differences in detoxification enzyme (P450, esterases and glutathione S-transferases) activities were found when the two strains were compared. In conclusion, our results demonstrate that Nice strain mites exhibited life history traits leading to higher fitness on two different hosts, which may be related with the higher invasive potential and outbreak risks of mites from lineage I.