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Biophysical Criteria Designating Agriculture Drought Affected Areas In The Context Of Climate Changes. Catalin Simota, Mihail Dumitru National Research & Development Institute for Soil Science Agrochemistry & Environment Bucharest, ROMANIA.
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Biophysical Criteria Designating Agriculture Drought Affected Areas In The Context Of Climate Changes Catalin Simota, Mihail Dumitru National Research & Development Institute for Soil Science Agrochemistry & Environment Bucharest, ROMANIA
Part of the work was supported by FP7 project:GS-Soil : Assessment and strategic development of INSPIRE compliant Geodata-Services for European Soil Data (eContentplus) 2009-2011 Based on the INSPIRE directive and its Implementing Rules GS Soil aims at establishing a European network to improve the access to spatial soil data for public sector bodies, private companies and citizens
Indicators & Use for policy • Ombrothermic Index (Bagnouls-Gaussen) – Environment policies (environment sensitive areas) DG Environment • Water Stress Index – Agriculture productivity - FAO • Length of Growing Periods – Designation of less favoured areas for agriculture – DG Agriculture
Indicators evaluation Water related indicators are evaluated at European scale using: a crop water balance simulation model (ROIMPEL) linked with: • soil database of Europe 1:1,000,000 • climate data for 1961-1990 baseline and 2020-2040 projections (ECHAM4, HADCM3).
Climate change scenarios HadCM3 and ECHAM4 were chosen as they represente the extremes in terms of both temperature and precipitation change. A1-SRES emission scenario was used for both climate models. Two versions of ECHAM4 were used: • ECHAM4 GGA1 with only Greenhouse Gas increase with 1% per year • ECHAM4GSA1 where Greenhouse Gas and Sulphate Aerosol with an increase rate of 1% per year is considered.
Ombrothermic index (Bagnouls-Gaussen)identifying drought related phanomena (indicated by positive BGI values) for the assessment of the environmentally sensitive areas to desertification in Mediterranean region Ombrothermic index summarizes hydrological stress on plant development and biomass formation • Ti is the mean air temperature for the month i in oC; • Pi is the total precipotation for month i in mm; • k represents the proportion of month during which 2Ti – Pi > 0 Bagnouls, F., H. Gaussen, 1953: Saison séche et indice xérothermique. Docum. Pour les Cartes des Prod. Veget. Serie : Generalité, 1 :1-49
Ombrothermic index (Bagnouls-Gaussen)1961 – 1990 2011-2040 HADCM3-A1FI2011-2040 ECHAM4 CO2 2011-2040 ECHAM4 CO2&S Shift to more drought affcted areas in Central and East Europe, France and Mediterranean region More severe conditions in 2011-2040 are predicted using ECHAM4-GGA1 for Central European countries, France and Mediterranean region, rather HADCM3-A1FI shows the largest extent of hidrologycal stress in the South of Iberic Peninsula
Water Stress Index The ratio between actual ETactual and potential evapotranspiration ETo considering as standard crop – grassland provides a good estimation for the effects of water stress on crop biomass development. • Arid zone: ETactual / ETo ≤ 0.3 • Semiarid zone: 0.3 < ETactual / ETo ≤ 0.5 • Dry subhumid zone: 0.5 < ETactual / ETo ≤ 0.65 • Humid zone: ETactual / ETo > 0.65
Water Stress Index1961 – 1990 2011-2040 HADCM3-A1FI2011-2040 ECHAM4 CO2 2011-2040 ECHAM4 CO2&S Mediterranean and South Balkan regions show the largest extension of semiarid (Spain, Greece) and dry subhumid conditions (South of France and Italy, South Balkans) during the baseline period (1961-1990) HADCM3 shows significant trends to desertification in this areas ECHAM4 – no significant changes
Length of Growing PeriodsEliasson, A., Terres, J.-M and C. Bamps, 2007: Common Biophysical Criteria for Defining Areas which are Less Favourable for Agriculture in Europe. Proceedings from the Expert Meeting 19-20th April, 2007 - The Institute for Environment and Sustainability, Joint Research Centre, Ispra, Italy. EUR 22735 EN, Luxembourg: Office for Official Publications of the European Communities Period during the year when both temperature and water supply limit the crop growth. Short growing periods are either reflecting dry conditions, cold conditions or a combination of both A day is not water limited if the ratio of daily actual and potential evapotranspiration exceeds 0.5: Very severe threshold: LGP < 60 days, Severe threshold LGP < 75 days
Length of Growing Periodsgrowth day counting for the period between last frost in spring and first frost in autumn1961 – 1990 2011-2040 HADCM3-A1FI2011-2040 ECHAM4 CO2 2011-2040 ECHAM4 CO2&S • The three climate change models give different results as compared with baseline: • for HADCM3-A1FI the highest trend to severe and very severe thresholds are for the Balkan Region and Central European countries (Poland, East of Germany); • for ECHAM4-GGA1 there is an improvement of this index even for South European regions; • for ECHAM4-GSA1 the trends to severe and very severe thresholds are for North-West Europe and British Islands.
Sensitivity of the Length of Growing Period to values of root front depth(Romania) Root front depth from soil type Root front depth from soil mechanical properties
Changes in spring wheat average yield between 2011-2040 ECHAM4 GGA1 (Greenhouse Gas 1% pa), ECHAM4GSA1 (Greenhouse Gas and Sulphate Aerosol 1% pa) scenarios and the baseline (1961-1990) For spring wheat the pattern of changes over Europe is very similar with that of length of growing period calculated for no frost time interval.
Changes in winter wheat average yield between 2011-2040 ECHAM4 GGA1 (Greenhouse Gas 1% pa), ECHAM4GSA1 (Greenhouse Gas and Sulphate Aerosol 1% pa) scenarios and the baseline (1961-1990) For winter crop the pattern of yield changes (slightly decrease for all Europe with highest decreases in Balkan and East Europe regions for ECHAM4 GGA1; decrease of yields in East and Central Europe for ECHAM4 Gsa1) is not similar with any indicators used for defining water stress.
CONCLUSIONS • No single index must be used as criteria for designation of areas affected by water limitation. Each indicator shows different patterns over Europe. Therefore, great care is needed if such indicators are to be used in designation of specific areas subject to different environment and agriculture policies (e.g. designation of areas less favored for agriculture).
CONCLUSIONS • Considering that the indicators will be used for the next future in implementing Community polices their values for climate change scenarios are very useful in designing proper measures. • The uncertainty induced by climate change predictions (different Global Circulation Models, different emission scenario), procedures for evaluating soil parameters needed for calculation, evaluation tools (simulation models) make this evaluation a difficult task. The best solution is to show the range of variation of indicators over all the possible climate and soil values.
CONCLUSIONS • Various indexes used for the evaluation of water affected areas are not always replacing the effects of climate changes on crop yields – mainly for winter crops.