Assessing the vulnerability of selected agro‐ecosystems in Central Asia to threats resulting from climate change – production and productivity of wheat Report of sub‐component 3 of the ADB funded project on Adaptation to Climate Change in Central Asia and People's Republic of China Rolf Sommer, Mariya Glazirina and Tulkun Yuldashev 15 January 2012 1 1 INTRODUCTION ..................................................................................................................... 4 2 METHODOLOGY ..................................................................................................................... 6 2.1 Agro‐ecological Zoning ..................................................................................................................... 6 2.2 Climate change scenarios ................................................................................................................. 8 2.2.1 Description of CC scenarios ................................................................................................................ 8 2.2.2 Daily data (weather generators) ........................................................................................................ 9 2.3 CropSyst model description ........................................................................................................... 14 2.4 Business‐as‐usual management ..................................................................................................... 16 2.4.1 Description ....................................................................................................................................... 16 2.4.2 Historic yields under business‐as‐usual ............................................................................................ 28 3 EXPERIMENTAL DATA AND CROP MODEL CALIBRATION ...................................... 30 3.1 Kazakhstan .................................................................................................................................... 30 3.1.1 Vozdvizhenka (Astana) ..................................................................................................................... 30 3.1.2 Kostanay .......................................................................................................................................... 32 3.1.3 Petropavlovsk .................................................................................................................................. 34 3.1.4 Shieli ................................................................................................................................................ 37 3.1.5 Calibration results Kazakhstan – Saratovskay 29 and Almaly ............................................................ 41 3.2 Kyrgyzstan ..................................................................................................................................... 45 3.2.1 KyrNIIZ ............................................................................................................................................. 45 3.2.2 ZhanyPakhta .................................................................................................................................... 47 3.2.3 Uchkhoz ........................................................................................................................................... 51 3.2.4 Daniyar ............................................................................................................................................ 53 3.2.5 Calibration results Kyrgyzstan – Adyr, Asyl, Intensivnaya, Kyal ......................................................... 58 3.3 Tajikistan ....................................................................................................................................... 61 3.3.1 Shahristan ........................................................................................................................................ 61 3.3.2 Khorasan .......................................................................................................................................... 64 3.3.3 Bakht ............................................................................................................................................... 67 3.3.4 Spitamen .......................................................................................................................................... 69 3.3.5 Faizabad ........................................................................................................................................... 72 3.3.6 Calibration results Tajikistan ‐ Kazakhskaya‐10, Navruz, Jagger ........................................................ 74 3.4 Uzbekistan ..................................................................................................................................... 78 3.4.1 Kuva ................................................................................................................................................. 78 3.4.2 Akkavak, Kroshka ............................................................................................................................. 81 3.4.3 Akaltyn ............................................................................................................................................. 85 3.4.4 Kushmanata ..................................................................................................................................... 91 3.4.5 Akkavak, Mars .................................................................................................................................. 96 3.4.6 Khorezm ......................................................................................................................................... 100 2 3.4.7 Calibration results Uzbekistan – Dustlik, Kroshka, Mars, Polovchanka, Kupava ............................. 102 4 IMPACT OF CLIMATE CHANGE ..................................................................................... 107 4.1 CC impact on yields .......................................................................................................................107 4.1.1 Overall impact ................................................................................................................................ 107 4.1.2 Country impact .............................................................................................................................. 108 4.2 Impact on crop phenology and physiology ....................................................................................114 4.2.1 Crop growth – days from emergence until maturity ...................................................................... 114 4.2.2 Maximum temperature during flowering ....................................................................................... 115 4.2.3 Minimum temperature during vegetative growth .......................................................................... 120 4.2.4 Irrigation requirements and transpiration use efficiency ............................................................... 120 5 GENERAL DISCUSSION .................................................................................................... 124 6 CONCLUSION ...................................................................................................................... 125 7 REFERENCES ................................................................................................................. 126 3 Acknowledgment This publication is a part of the initiative of the International Center for Agricultural Research in the Dry Areas (ICARDA) addressing the assessment of the impact of Climate Change on the wheat production in the different agroecological ecosystems in the 4 Central Asian countries (Kazakhstan, Kyrgyzstan, Tajikistan an Uzbekistan) in order to achieve sustainable, equitable and productive use and conservation of natural resources, including water, soils and biodiversity. We are grateful to the Asian Development Bank for providing financial support for this study under the Regional Technical Assistance (RETA 6439) project entitled “Climate Change adaptation in Central Asia and People’s Republic of China”. We would also like to thank our partners from national research institutions: Drs. Azimbay Otarov and Mariya Ibraeva (Kazakh Research Institute of Soil Science and Agro Chemistry after U.U.Uspanov, Kazakhstan), Dr. Lyudmila Martynova (Kyrgyz Research Institute of Crop Husbandry, Kyrgyzstan), Dr. Malik Bekenov (Ministry of Agriculture, Kyrgyzstan), Drs. Bobisho Kholov, Nasim Ibragimov, Rakhmon Kobilov, Sharif Karaev, Mirzo Sultonov (Institute of Soil Science of Tajik Academy of Agricultural Science, Tajikistan), Drs. Feruza Khasanova, Yusup Esanbekov, Sobir Isaev, Shovkat Abdurahimov (Uzbek Cotton Growing Research Institute, Uzbekistan), Dr. Rahimjan Ikramov and Mrs. Larisa Shezdyukova (Central Asian Scientific Research Institute for Irrigation (SANIIRI), Uzbekistan), as well as national hydrometeorological services of four CA countries. Without their active participation, consultations and support it would not have been possible to collect all the data for the study. Introduction In 2009, ICARDA in partnership with scientists from the national agricultural research system of Kazakhstan, Kyrgyzstan, Uzbekistan, Tajikistan and China launched a new multi‐disciplinary project on the “Adaptation to Climate Change in Central Asia and People's Republic of China” funded by the Asian Development Bank for a period of 3 years. The project builds on the notion that the majority of the rural population in Central Asia rely on agriculture and that climate change (CC) could negatively affect rural livelihoods. Regional studies of the impacts of CC are sparse, and those available rely on crude assumptions on the biophysical characteristics of crops, soils and climate as well as the agronomic management practices in the region. Little details are known about the vulnerability of the rural population and food security/crop production in Central Asia in response to CC. The overall objective of the project thus was to increase knowledge in the field of climate change and its potential impact in Central Asia. Sub‐ component 3 of the project was about “Assessing the vulnerability of selected agro‐ecosystems in Central Asia to threats resulting from climate change – production and productivity of wheat”. The specific objectives of this sub‐component were to develop climate change scenarios for selected major agro‐ecological zone, to assess the biophysical impact of CC on wheat productivity and to develop, if rendered indispensible, agronomic coping strategies to mitigated potentially negative impacts of CC. The following workflow was pursued: 1) In close collaboration with partners from the national research institutes in Kazakhstan (focal point: Dr. Otarov), Kyrgyzstan (Dr. Bekenov), Tajikistan (Dr. Kholov) and Uzbekistan (Dr. Ikramov), 4 available (historic) data sets on the field testing of various wheat varieties located in all major agro‐ecological zones of Central Asia were collected. Available results (grain yield, straw yield, N‐ uptake, phenological characteristics, etc.) as well as accompanying soil characteristics were screened and structured. Data sets from altogether 18 sites for 14 different bread wheat cultivars could be secured for this purpose. At the same time, an effort was made to acquire long‐term daily time step meteorological data for each location. Such data in part were available at ICARDA (ICARDA‐GISU weather database), could be downloaded from the internet, were provided free of charge by, or purchased from, the Central Asian national meteorological services. 2) Major biophysical model parameters of the daily time step crop‐soil simulation model, CropSyst (Stöckle et al. 2003), were calibrated to the available data sets. 3) Business‐as‐usual (BAU) management scenarios for each location were defined using information acquired by the socio‐economist colleagues during their farmer‐field evaluation/ interviewing phase along with national recommendations. For each site, three different BAU managements were defined: poor management, average management and above‐average management. 4) Using available meteorological data, the weather data generating software LARS‐WG (Semenov and Barrow 1997) was applied to generate stochastic daily time‐step weather data for the (historic) period 1961‐1990. 5) ICARDA's GIS‐unit (De Pauw and co‐workers) provided regionally downscaled climate change (CC) maps for Central Asia derived from a range of Global Climate Models (GCMs). De Pauw et al. (see separate report) distinguished three future periods, namely immediate‐future (year 2011‐2040), mid‐term future (2041‐2070) and long‐term future (2071‐2100). They furthermore considered/downscaled results of 17 GCMs each of it describing the climatic consequences of the two IPCC Emission Scenarios (SRES) A1B and A2. Thus, six different CC weather data sets were generated for each site, namely A1B immediate future, A1B mid‐term future, A1B long‐term future, A2 immediate future, A2 mid‐term future and A2 long‐term future, each comprising 50 years of data. 6) The CropSyst model was used to simulate the effect of the three different BAU‐scenarios under (one) historic and the six different CC weather conditions for each of the 18 sites. 7) Results of this point‐scale modeling were extrapolated to Central Asia using available maps on the distribution of the 14 wheat varieties, the agro‐ecological zoning done by ICARDA, precipitation and temperature patterns as well as maps on the length of growing period. Results are presented in a separate report (De Pauw et al.). The present report provides an in‐depth description of the study. Results of the impact of CC on wheat productivity are presented and discussed and conclusions provided. 5 1 Methodology 1.1 Agroecological Zoning One of the main criteria of selecting suitable sites for this study was their representativeness. This was assured by matching site locations with major agro‐ecological zones (AEZ) of Central Asia, which are most suitable for cultivation of wheat and as had been identified by ICARDA's GIS‐unit (de Pauw and co‐workers; De Pauw 2010; Figure 1 and Table 1). For a detailed description, we refer to the separate report on the GIS sub‐component of the project. Figure 1: Agro‐ecological zones suitable for cultivation of wheat in Central Asia (de Pauw, 2010), and sites selected for the study (red dots number 1‐19) Table 1: Description of agro‐ecological zones of Central Asia suitable for the cultivation of wheat AEZ Description Countries (in order of abundance) 310 Irrigated wheat in an arid climate with cold winter Uzbekistan, Kazakhstan, and hot summer Tajikistan 510, 521 Irrigated or rainfed wheat in a semi‐arid climate Kazakhstan, Uzbekistan, with cold winter and mostly warm summer Tajikistan, Kyrgyzstan 610, 621 Irrigated or rainfed wheat in mostly semi‐arid Kazakhstan, Kyrgyzstan climate with mostly cold winters and mild summer 821, 822, 823 Rainfed wheat in sub‐humid climate with cold Kazakhstan, Kyrgyzstan, winters and mild summer Uzbekistan 1010, 1022, Irrigated or rainfed wheat in a humid climate with Kazakhstan, Tajikistan, 1023 cold winters and mild summers Kyrgyzstan, Uzbekistan The selected sites cover whole Central Asia and are located in the most of the above‐mentioned AEZs (see Figure 1 and Table 2). Chapter 4 provides a detailed sites description. 6 Table 2: Selected sites and their respective Agro‐Ecological Zones (AEZ) Country Site name AEZ # on map* Irrigation Kazakhstan Astana 521 2 Rainfed Kostanay 521 18 Rainfed Petropavlovsk 821 19 Rainfed Shieli 310 1 SI Kyrgyzstan Daniyar 510 6 SI KyrNIIZ 510 7 SI Uchkhoz 510 3 SI ZhanyPakhta 510 4 Rainfed Tajikistan Bakht 510 11 SI Faizabad 1032 8 Rainfed Khorasan 510 10 Rainfed Shahristan 532 9 SI Spitamen 510 5 SI Uzbekistan Akaltyn 510 14 SI Akkavak 510 17 SI Khorezm 310 13 Full Irrig. Kushmanata 510 15 Full Irrig. Kuva 310 16 Full Irrig. *Due to lack of sufficient calibration data site no. 12, was excluded from further analyses 7 1.2 Climate change scenarios 1.2.1 Description of CC scenarios From the range of scenarios published by the Intergovernmental Panel on Climate Change (IPCC) on the basis of prediction on future economic growth, energy use and resulting greenhouse gas emissions as have been first mentioned in the IPCC Special Report on Emissions Scenarios (SRES; IPCC, 2000), the following two scenarios were considered in the investigation: A2, which reflects a more pessimistic future, assuming a continuous population growth, increasing divergence between regions, less transfer of technological innovations. The corresponding change in global surface temperature, comparing 2090‐99 with 1980‐99 is estimated to 2.0‐5.4 °C (average best estimate: 3.4 °C) A1b, which is neither optimistic nor pessimistic. It assumes population stabilization, continued globalized world, balance between fossil‐intensive and non‐fossil energy sources. The corresponding change in global surface temperature (2090‐99 vs. 1980‐99) is estimated to 1.7‐ 4.4 °C (average best estimate: 2.8 °C).For further details see IPCC (2007 page 18). Related projections on atmospheric CO concentration are given in Figure 2. SRES ‐ A2 CO 2 2 concentrations were projected to surpass A1B concentration from 2050 onwards. 1000 m) p n (p 800 SRES A1B o ati SRES A2 r 600 nt e c n o 400 c O2 C 200 1950 1975 2000 2025 2050 2075 2100 Year Figure 2: Increase of the atmospheric CO concentration as predicted by SRES A1B and A2 (redrawn from 2 IPCC, 2000) The values of CO concentration used in the simulation of CC impact are listed in the Table 3. 2 Table 3: Atmospheric CO2 concentrations for the three distinguished futures under SRES A1B and A2; immediate future = 2011‐2040, mid‐term future = 2041‐2070, long‐term future = 2071‐2100 Emission Scenario Future Atmospheric CO 2 concentration (ppm) Baseline 350 A1B Immediate 435 Mid‐term 544 Long‐term 656 A2 Immediate 435 Mid‐term 550 Long‐term 726 8 The IPCC furthermore released results of global climate simulations using the published Emission Scenarios as baseline. From the outputs of 23 global circulation models (GCM), on which the IPCC report is based, 17 GCM results were selected by ICARDA's GIS‐unit (de Pauw and co‐workers) for this study. The minimum requirement for a GCM output dataset to be selected was the availability of average temperature and precipitation data for the two above‐mentioned GHG emission scenarios and three time horizons, namely immediate future (year 2011‐2040), mid‐term future (2041‐2070) and long‐term future (2071‐2100). Subsequently, the seven models listed in the Table 4 were chosen as most realistic/most advanced GCMs. Among them are BCCR‐BCM2.0, CSIRO‐MK3.0, MIROC3.2, CGCM3.1 and CNRM‐CM3, which have complete and public available datasets for precipitation, maximum, minimum and mean temperature, and ECHAM5/MPI‐OM, GFDL‐CM2.0 for which full precipitation and mean temperature datasets are available. Table 4: GCM models used in investigation No Name Country Year Resolution (°) Source and vertical levels) 1 BCCR‐ Norway 2005 2.8 x 2.8 (31) http://www.ipcc‐data.org/ BCM2.0 https://esg.llnl.gov:8443/home/publicHomePage.do 2 CSIRO‐MK3.0 Australia 2001 1.9 x 1.9 (18) http://www.ipcc‐data.org/ https://esg.llnl.gov:8443/home/publicHomePage.do 4 MIROC3.2 Japan 2004 2.8 x 2.8 (20) http://www.ipcc‐data.org/ 8 CGCM3.1(T6 Canada 2005 2.8 x 2.8 (31) http://www.ipcc‐data.org/ 3) http://www.cccma.ec.gc.ca/data/cgcm3/cgcm3.shtml 9 CNRM‐CM3 France 2005 2.8 x 2.8 (45) http://www.ipcc‐data.org/ https ://esg.llnl.gov:8443/home/publicHomePage.do http://www.mad.zmaw.de/projects‐at‐ md/ensembles/experiment‐list‐for‐stream‐1/cnrm‐cm3/ 10 ECHAM5/ Germany 2003 1.9 x 1.9 (31) http://www.ipcc‐data.org/ MPI‐OM 12 GFDL‐CM2.0 USA 2005 2 x 2.5 (24) http://www.ipcc‐data.org/ 1.2.2 Daily data (weather generators) Since CC data were available only in form of absolute deviation of monthly temperature (∆T) and relative deviation of monthly sum of precipitation (∆P) from historic data (reference period of 1961‐ 1990), there was a need to produce multiple‐year climate change data at the daily time scale, which is required for crop modeling. Stochastic weather generators (WGs) are commonly used for this purpose. Based on comparative analysis of WG’s outputs under Central Asian climate variability conditions the LARS‐WG (Semenov and Barrow, 1997) was chosen as most suitable weather generator for producing the required crop modeling weather data sets. In contrast to the other weather generators, LARS‐WG uses an alternating renewal model for precipitation occurrence (Semenov et al., 1998). However, there was a shortcoming in regard of the applicability of LARS‐WG: its output is limited to maximum (T ) and minimum temperature (T ), solar radiation and precipitation. Since max min CropSyst requires seven meteorological parameters, namely T , T , precipitation (P), solar max min radiation (Rs), maximum relative humidity (RHmax), minimum relative humidity (RHmin) and wind speed (W), the ClimGen weather generator (Stöckle et al., 1998), which is part of the CropSyst modeling suite, was used for estimating missing parameters. Table 5 provides a comparative description of the underlying methods used in both WGs. 9 Table 5: Comparative description of the methods used in the LARS‐WG and ClimGen weather generators ClimGen LARS‐WG Developers Stöckle & Nelson & Campbell Semenov & Barrow & Racsko Precipitation Definition of wet day Daily precipitation > 0.25 mm Daily precipitation > 0.1 mm Determination of Transition probabilities of a first‐order 2‐state Lengths of alternate wet and dry sequences precipitation status for a Markov chain applied to the previous day's status. chosen from a semi‐empirical distribution fitted given day Transitional probabilities can be determined to the observed series. Separate parameters directly from daily data if long records (>20 years) are calculated for each month. are available. They can also be estimated from the fraction of wet days in a month. Separate probabilities are calculated for each month. Daily distribution Two‐parameter Weibull distribution. One of the Semi‐empirical distribution parameters was found by Selker and Haith (Selker and Haither, 1990) to be 0.75 after optimization using data from several locations (including Central Asia) Parameters Separate parameters are calculated for each monthSeparate parameters are calculated for each month Minimum temperature Daily distribution Normal distribution Normal distribution Parameters The mean and standard deviation of the normal The mean and standard deviation of the normal vary daily. vary daily. These parameters are obtained by fitting Fourier series to the means and standard deviations of the observed data throughout the year (grouped into months) Conditioned on Yes Yes. Separate Fourier series are fitted for wet precipitation status? and dry days. Correlation Cross‐correlation between maximum temperature, Constant lag 1 auto‐correlation. Pre‐set cross‐ minimum temperature and radiation. correlation between maximum and minimum temperature Maximum temperature Daily distribution Normal distribution Normal distribution Parameters The mean and standard deviation of the normal The mean and standard deviation of the normal vary daily. vary daily. These parameters are obtained by fitting Fourier series to the means and standard deviations of the observed data throughout the year (grouped into months) Conditioned on Yes Yes. Separate Fourier series are fitted for wet precipitation status? and dry days. Correlation Cross‐correlation between maximum temperature, Constant lag 1 auto‐correlation. Pre‐set cross‐ minimum temperature and radiation. correlation between maximum and minimum temperature Radiation Daily distribution Normal distribution Semi‐empirical distribution Parameters The mean and standard deviation of the normal Separate parameters are calculated for each vary daily. month Conditioned on Yes Yes. Separate parameters are calculated for wet precipitation status? and dry days for each month. Correlation Cross‐correlation between maximum temperature, Constant lag 1 auto‐correlation. minimum temperature and radiation. Relative humidity of Calculated via dew point temperature and vapor the air pressure calculation. Two years of humidity and temperature data are sufficient. Wind speed Wind speed generated using Weibull distribution. Source http://www.bsyse.wsu.edu/cropsyst/ClimGen/inde http://www.rothamsted.bbsrc.ac.uk/mas‐ x.html models/larswg.php 10
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