Humanity is heading toward the major challenge of having to increase food production by about 50% by 2050 to cater for an additional three billion inhabitants, in a context of arable land shrinking and degradation, nutrient deficiencies, increased water scarcity, and uncertainty due to predicted climatic changes. Already today, water scarcity is probably the most important challenge, and the consensual prediction of a 2–4°C degree increase in temperature over the next 100 years will add new complexity to drought research and legume crop management. This will be especially true in the semi-arid tropic areas, where the evaporative demand is high and where the increased temperature may further strain plant–water relations. Hence, research on how plants manage water use, in particular, on leaf/root resistance to water flow will be increasingly important.
Temperature increase will variably accelerate the onset of flowering by increasing thermal time accumulation in our varieties, depending on their relative responses to day length, ambient, and vernalizing temperature, while reducing the length ofthe growing period by increasing evapotranspiration. While the timeframe for these changes (>10–20 years) may be well in the realm of plant adaptation within breeding programs, there is a need for today’sbreeding to understand the key mechanisms underlying crop phenology at a genotype level to better balance crop duration with available soil water and maximize light capture. This will then be used to re-fit phenology to new growing seasons under climate change conditions. The low water use efficiency, i.e., the amount of biomass or grain produced per unit of water used, under high vapor pressure deficit, although partly offset by an increased atmospheric CO2 concentration, would also require the search of germplasm capable ofmaintaining high water use efficiency under such conditions. Recent research has shown an interdependence ofC and N nutrition in the N performance of legumes, a balance that may be altered under climate change.
Ecophysiological models will be crucial in identifying genotypes adapted to these new growing con- ditions. An increased frequency of heat waves, which already happen today, will require the development of varieties capable of setting and filling seeds at high temperature. Finally, increases in temperature and CO2 will affect the geographical distribution of pests, diseases, and weeds, presenting new challenges to crop management and breeding programs.
Grain legumes contribute significantly to total world food production. Legumes are the primary source of dietary proteins in many developing countries, where protein hunger and malnutrition are widespread. Grain legumes germplasm constitute 15% of the 7.4 M accessions preserved globally. Nearly, 78% of the CGIARs, 0.217 M accessions, have been characterized, compared to 34% of national genebank collections. Interestingly, limited data on grain quality are available as the primary focus has been on morpho-agronomic traits. Clearly, more resources should be targeted on biochemical evaluation to identify nutritionally rich and genetically diverse germplasm.
The formation of core and mini core collections has provided crop breeders with a systematic yet manageable entry point into global germplasm resources. These subsets have been reported for most legumes and have proved useful in identifying new sources of variation. They may however not eliminate the need to evaluate entire collections, particularly for very rare traits. Molecular characterization and association mapping will further aid to insights into the structure of legume diversity and facilitate greater use of collections. The use of high resolution elevational climate models has greatly improved our capacity to characterize plant habitats and species adaptive responses to stresses. Evidence suggests that there has been increased use of wild relatives as well as new resources resulting from mutagenesis to enhance the genetic base of legume cultigens.
Over the past decade, efforts to move towards a low carbon economy have been increasingly coupled with the acknowledgement that we also need to develop climate resilient economies, capable of adapting and responding to changes in climate. To shift society in these directions we need to quantify impacts in relation to these objectives and develop cost-effective interventions. Techniques for quantifying greenhouse gas emissions are relatively well established and enable identification of hotspots where there is emissions reduction potential.However, there are no established techniques to assess and quantify adaptation vulnerability issues and identify hotspots for intervention.
This paper presents work undertaken at a European level with the objective of identifying potential hotspots where ecosystem services may be vulnerable to climate change and thus where intervention may be required under the European Rural Development Programme. A pragmatic and relatively simple approach is presented, based on data that is readily available across Europe. The vulnerability assessments cover: Water (quality: dilution and filtration, regulation: flooding and provision); soils (erosion and organic matter); and biodiversity (forest fires, migration and pollination). The framework and assessments presented are considered fit for purpose (at a basic level) and they are potentially valuable tools for targeting limited resources to achieve desirable outcomes. They also contribute towards providing a better understanding of the climate change challenges we face and support the formulation of solutions to optimally address those challenges There is scope to further improvement and a number of options are discussed and explored within this paper.
Eight years of fire weather data from sixteen representative weather stations within the Boreal Forest Natural Region of Alberta were used to compile reference weather streams for low, moderate, high, very high and extreme Fire Weather Index (FWI) conditions. These reference weather streams were adjusted to create daily weather streams for input into Prometheus - the Canadian Wildland Fire Growth Model. Similar fire weather analyses were completed using Canadian Regional Climate Model (CRCM) output for northern Alberta (174 grid cells) to generate FWI class datasets ( temperature, relative humidity, wind speed, Fine Fuel Moisture Code, Duff Moisture Code and Drought Code) for 1 x, 2 x and 3 x CO2 scenarios.
The relative differences between the CRCM scenario outputs were then used to adjust the reference weather streams for northern Alberta. Area burned was calculated for 21 fires, fire weather classes and climate change scenarios. The area burned estimates were weighted based on the historical frequency of area burned by FWI class, and then normalized to derive relative area burned estimates for each climate change scenario. The 2 x and 3 x CO2 scenarios resulted in a relative increase in area burned of 12.9 and 29.4% from the reference 1 x CO2 scenario.
Summer fires frequently rage across Mediterranean Europe, often intensified by high temperatures and droughts. According to the state-of-the-art regional fire risk projections, in forthcoming decades climate effects are expected to become stronger and possibly overcome fire prevention efforts. However, significant uncertainties exist and the direct effect of climate change in regulating fuel moisture (e.g. warmer conditions increasing fuel dryness) could be counterbalanced by the indirect effects on fuel structure (e.g. warmer conditions limiting fuel amount), affecting the transition between climate-driven and fuel-limited fire regimes as temperatures increase.
Here we analyse and model the impact of coincident drought and antecedent wet conditions (proxy for the climatic factor influencing total fuel and fine fuel structure) on the summer Burned Area (BA) across all eco-regions in Mediterranean Europe. This approach allows BA to be linked to the key drivers of fire in the region. We show a statistically significant relationship between fire and same-summer droughts in most regions, while antecedent climate conditions play a relatively minor role, except in few specific eco-regions. The presented models for individual eco-regions provide insights on the impacts of climate variability on BA, and appear to be promising for developing a seasonal forecast system supporting fire management strategies.
Conservation agriculture (CA) in the last decades has been spread in several parts of the world, especially in South and North America and Australia. In Italy, however, its adoption is often restrained by the risk to have a reduction in crop production in the early years of transition from conventional (CT) to CA. To quantify sufficient financial support to promote no-tillage and CA, a mini-review about main effects of CA was conducted.
The effect on crop yield, soil fertility - especially as it is influenced by the chemical, physical and microbiological factors - on soil compaction, the economic balance of the farm and the cost of equipment for direct seeding, the influence of environment on soil erosion, water retention, emissions of greenhouse gases, and carbon sequestration are briefly treated. The paper reports findings from national and international scientific literature and some results from long-term experiments conducted in Southern Italy.
The main conclusions are about the reduction of yield in the first years of transition from CT to CA (from -5 to - 10%), an improvement of soil fertility (soil organic carbon increases in the upper layers), reduction of management cost (less machinery operations), improvement of soil C sequestration (in specific conditions), a reduction of greenhouse gases emission and soil erosion risk. The paper provides the scientific basis in order to justify and quantify the amount to be paid to the farmers who decide to adopt the model of CA, oriented to protect the agro-ecosystem and to promote the principle of subsidiarity. Finally, a proposal of public subsidy in cash and for machinery purchase has been described.
Many of the species at greatest risk of extinction from anthropogenic climate change are narrow endemics that face insurmountable dispersal barriers. In this review, I argue that the only viable option to maintain populations of these species in the wild is to translocate them to other locations where the climate is suitable. Risks of extinction to native species in destination areas are small, provided that translocations take place within the same broad geographic region and that the destinations lack local endemics. Biological communities in these areas are in the process of receiving many hundreds of other immigrant species as a result of climate change; ensuring that some of the 'new' inhabitants are climate-endangered species could reduce the net rate of extinction.
In the last few years, in several parts of the world, under extreme weather conditions, several catastrophic fires have taken place. These fires are called mega-fires. They are not just large fires but extreme events in their behavior, difficulty to control and impacts. Portugal historically has little experience with mega-fires, but recent fire events exacerbated by climate change and landscape management has changed this situation. In the year 2003, the worst and largest wildfires were ever recorded in the Algarve region and in the central region of Portugal.
However, this paper focuses on the Algarve region, using primary (i.e. questionnaires, interviews, satellite images, and fieldwork) and secondary data (i.e. Portuguese wildfire database, central and local governments' fire damages reports). Using wildfire ecological and socio-economic impacts as an important criterion to classify an event as a mega-fire, this paper conclude that two mega-fires occurred in 2003 in the Algarve Region. Taking into account the weakness in Portuguese wildfire impacts reporting process, it is proposed a checklist of categories of damages and losses to support future data acquisition.
Considering that mega-fires are a new reality in Portugal, this paper shows that increasing suppression capabilities in terms of means, readiness and effectiveness are important to avoid small fires to become mega-fires in days of critical fire danger. Nevertheless, facing the impossibility of changing the extreme weather conditions, given the complexity and uncertainty surrounding mega-fires occurrence and severity, the main challenge is to improve wildfire risk reduction instead of focusing only on fire suppression.
This paper proposes a framework which conceptualizes fire impacts as a result of interaction between fire behavior, vulnerability and suppression capabilities. It can be used for promoting wildfire prevention and mitigation. It is urgent to enhance prevention measures in order to change fire behavior and reduce vulnerability of ecosystems and societies, as well as to increase the engagement of communities in wildfire risk management.
There is a widely recognized need in the scientific and policy communities for probabilistic estimates of climate change impacts, beyond simple scenario analysis. Here we propose a methodology to evaluate one major climate change impact - changes in global average yields of wheat, maize, and barley by 2030 - by a probabilistic approach that integrates uncertainties in climate change and crop yield responses to temperature, precipitation, and carbon dioxide.
The resulting probability distributions, which are conditional on assuming the SRES A1B emission scenario and no agricultural adaptation, indicate expected changes of +1.6%, 14.1%, 1.8% for wheat, maize, and barley, with 95% probability intervals of ( 4.1, +6.7), ( 28.0, 4.3), ( 11.0, 6.2) in percent of current yields, respectively. This fully probabilistic analysis aims at uantifying the range of plausible outcomes and allows us to gauge the relative importance of different sources of uncertainty.
The Mediterranean basin is the largest world area having specific climatic conditions suitable for olive cultivation, which has a great socio-economic importance in the region. However, the Mediterranean might be particularly affected by climate change, which could have extensive impacts on ecosystems and agricultural production. This work focussed on the climate change impact on olive growing in the Mediterranean region considering the possible alterations of cultivable areas, phenological dates, crop evapotranspiration and irrigation requirements. Monthly climate data, with a spatial resolution of 0.25°×0.25° (latitude by longitude), have been derived from Regional Climate Models driven by ECHAM5 for the A1B scenario of the Special Report on Emissions Scenarios (SRES).
The data used in the analysis represented two time periods: (i) present, called year 2000 (average values for the period 1991-2010), and (ii) future, called year 2050 (average values for the period 2036-2065). The areas suitable for olive cultivation were determined using the temperature requirements approach known as the Agro Ecological Zoning method. Crop evapotranspiration and irrigation requirements were estimated following the standard procedure described in the FAO Irrigation and Drainage Paper 56. Results showed that the potentially cultivable areas for olive growing are expected to extend northward and at higher altitudes and to increase by 25% in 50 years. The olive flowering is likely to be anticipated by 11±3 days and crop evapotranspiration is expected to increase on average by 8% (51±17mmseason-1).
Net irrigation requirements are predicted to increase by 18.5% (70±28mmseason-1), up to 140mm in Southern Spain and some areas of Algeria and Morocco. Differently, effective evapotranspiration of rainfed olives could decrease in most areas due to expected reduction of precipitation and increase of evapotranspirative demand, thus making it not possible to keep rainfed olives' production as it is at present.