Farmer Rice Field Adaptation Technology for Rice-wheat Cropping System of Pakistan in Future changing Climate

English Abstract:

Climate change is a significant threat to crop production and food security in Pakistan. Climate change hazards would be more devastating in future because there would be 2.8 °C rise in maximum and 2.2 °C in minimum temperature for mid-century (2040-2069) in Rice-Wheat cropping system of Pakistan. There is an urgent need for improved climate modeling and forecasting that can provide a basis for informed decision-making and the implementation of adaptation strategies. Crop Growth and Global Circulation Models are helpful tools to assess the climate change impact and can also provide a basis for informed decision support and the development of adaptation strategies for the stakeholders. Proposed study was planned to ensure food security by quantifying the future climate variability and adapting the climatic resilient technology. Crop growth models (DSSAT & APSIM) were calibrated and evaluated on experimental field data to develop the robust genetic coefficients. Models were validated using farmers’ field (155) data of five districts in RW cropping system. A close agreement was observed between farmer and simulated fine rice yield with good statistical indices such as Root Mean Square Error of 409 kg ha^-1 and 440 kg ha^-1 with d-index (0.80 and 0.78) for DSSAT and APSIM, respectively. Climate change impact was quantified with crop models using baseline (1981-2010) and future climate data of five General Circulation Models (CCSM4, GFDL, HadGEM, MIROC5, and MPI-ESM) for mid-century (2040-2069). Mean yield reduction for DSSAT ranged between 8 to 30 % while for APSIM yield reduction was 14 to 19 % with five GCMs. Adaptation technology was developed to cope with the drastic impacts of changing climate. To achieve high productivity and meet the need of growing population, it would be required to increase the planting density, fertilizer use and reduced the irrigation amount up to 15% over current which was considered as one of the adaptation strategy for promising cultivars with greater potential. Due to high temperature the cropping seasons will be affected and 5 days earlier transplanting of nursery over current would be recommended. These strategies have a significant impact in reducing the vulnerabilities of the changing climate with 33% improvement in fine rice yield to sustain food security in Rice-wheat cropping system.