Abstract: The phenological development of cereal crops from emergence through flowering to maturity is largely controlled by temperature, but also affected by day length and potential physiological stresses. Responses may vary between species and varieties. Climate change will affect the timing of cereal crop development, but exact changes will also depend on changes in varieties as affected by plant breeding and variety choices. This study aimed to assess changes in timing of major phenological stages of cereal crops in Northern and Central Europe under climate change. Records on dates of sowing, flowering, and maturity of wheat, oats and maize were collected from field experiments conducted during the period 1985-2009. Data for spring wheat and spring oats covered latitudes from 46 to 64°N, winter wheat from 46 to 61°N, and maize from 47 to 58°N. The number of observations (site-year-variety combinations) varied with phenological phase, but exceeded 2190, 227, 2076 and 1506 for winter wheat, spring wheat, spring oats and maize, respectively. The data were used to fit simple crop development models, assuming that the duration of the period until flowering depends on temperature and day length for wheat and oats, and on temperature for maize, and that the duration of the period from flowering to maturity in all species depends on temperature only. Species-specific base temperatures were used. Sowing date of spring cereals was estimated using a threshold temperature for the mean air temperature during 10 days prior to sowing. The mean estimated temperature thresholds for sowing were 6.1, 7.1 and 10.1°C for oats, wheat and maize, respectively. For spring oats and wheat the temperature threshold increased with latitude. The effective temperature sums required for both flowering and maturity increased with increasing mean annual temperature of the location, indicating that varieties are well adapted to given conditions. The responses of wheat and oats were largest for the period from flowering to maturity. Changes in timing of cereal phenology by 2040 were assessed for two climate model projections according to the observed dependencies on temperature and day length. The results showed advancements of sowing date of spring cereals by 1-3 weeks depending on climate model and region within Europe. The changes were largest in Northern Europe. Timing of flowering and maturity were projected to advance by 1-3 weeks. The changes were largest for grain maize and smallest for winter wheat, and they were generally largest in the western and northern part of the domain. There were considerable differences in predicted timing of sowing, flowering and maturity between the two climate model projections applied.

Abstract: Integrated conservation and management of agricultural areas affected by the current global warming represents a priority at international level following the implementation of the principles of sustainable agriculture and adaptation measures. Transylvanian Plain (TP), with an area of 395,616 ha is of great agricultural importance for Romania, but with an afforestation degree of only 6.8% and numerous degradation phenomena of farmland, it has the lowest degree of sustainability to climate change. Monitoring of agro-climatic indicators and their evolution in between 2008-2014 and the analysis of the obtained data underlie the technological development of recommendations tailored to current favorable conditions for the main crops. Results obtained show that: the thermal regime of the soils in TP is of mesic type and the hydric regime is ustic; multiannual average of temperature in soil at 10 cm depth is 11.40ºC, respectively at 50 cm depth is 10.24ºC; the average yearly air temperature is 11.17ºC; multiannual average of soil moisture is 0.227 m3/m3; Multiannual average value of precipitation is 466.52 mm. During the studied period, compared with data series available (1961-1990; 1901-2000), clear decrease of the average quantities of rainfall especially during critical periods for crops, and increases in average temperatures for the entire year can be noticed. Between June and August the highest temperature difference were recorded, differences of +3.09°C to +3.65°C. There is an increase phenomenon of drought and heat; determined indicators show that most values, 61.11%, are commensurate with a semiarid climate. Aggression peaks are in February-April, July, and October-November, and for the whole period, in 19.43% of the cases are favorable and very favorable conditions for triggering erosion. Recommended agro-technical measures to limit and counteract the effects of drought, as a climatic phenomenon with major risk to agriculture in TP, refer to: i) use of a biological material resistant to water stress and heat; ii) use of management practices favorable for accumulation of, conservation and the efficient use of water from rainfall; iii) operating a system of conservation agriculture based on soil protection and desertification avoidance.

Abstract: Rather than on crop modelling only, climate change impact assessments in agriculture need to be based on integrated assessment and farming systems analysis, and account for adaptation at different levels. With a case study for Flevoland, the Netherlands, we illustrate that (1) crop models cannot account for all relevant climate change impacts and adaptation options, and (2) changes in technology, policy and prices have had and are likely to have larger impacts on farms than climate change. While crop modelling indicates positive impacts of climate change on yields of major crops in 2050, a semiquantitative and participatory method assessing impacts of extreme events shows that there are nevertheless several climate risks. A range of adaptation measures are, however, available to reduce possible negative effects at crop level. In addition, at farm level farmers can change cropping patterns, and adjust inputs and outputs. Also farm structural change will influence impacts and adaptation. While the 5th IPCC report is more negative regarding impacts of climate change on agriculture compared to the previous report, also for temperate regions, our results show that when putting climate change in context of other drivers, and when explicitly accounting for adaptation at crop and farm level, impacts may be less negative in some regions and opportunities are revealed. These results refer to a temperate region, but an integrated assessment may also change perspectives on climate change for other parts of the world.