Iran-Fars-Sarvestan-Dehnow
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Iran-Fars-Sarvestan-Dehnow A case of “Response Farming” in Iran in three episodes Sarvestan in the drought episodes Page 1 By Alireza Sodagari, CEO Sistana-Scada (a.sodagari@sistana-scada) The Site The Iranian site is a “Pistachio Orchard” located at “29. 12. 03N & 53.11.11E” in the South Western province Fars next to Sarvestan county center. The orchard is about 50 hectares and the trees were planted in rows in 1991. Mr. Mahani, the grower, was elected “Best Grower” for several years. Episode 1 ( from one Province to another Province) In 1990s, Mr. Mahani, originally from Kerman, the cradle of Pistachio growing in Iran, migrated to Fars province, in search of new potential sites for pistachio. Other growers from Kerman did the same and started growing pistachio in other suitable areas of the country. This recent act of response farming (e.g. Stigter et al., 2013) happened in response to lack of suitable land, shortage of water and soil salinity increase in this traditional pistachio growing area. Meanwhile still other actions were necessary due to the emerging “Climate Change” causing drought conditions in the newly stablished pistachio growing area. Episode 2 ( introducing a new crop) Traditionally, the crops for Sarvestan County are Wheat, Maize, Melon and Tomato. These are rather water consuming crops. The absence of proper irrigation systems and long lasting drought conditions from 2004 onwar led to drying water wells and desertification. Many farmers left the county and emigrated to Shiraz, the capital of the province. South West Iran is experiencing an unusually severe drought. In the last ten years drought has put an extensive pressure on the underground water reservoirs. In such conditions, crop pattern changes in the context of response farming were a mandate for survival of the farmer’s livelihood. Pistachio trees are more adaptable to dryness and salinity. The first orchards were planted in 1991 and they were booming during the severe drought period from 2004 onward. In the 2004-2014 decade, the severe drought in Sarvestan dried out water resources and created the necessity of another adaptation to the new situation. Sarvestan in the drought episodes Page 2 Fig. 1 Drought conditions shown by Normalized Difference Vegetation Index (NDVI) change form 2004 onward [low, positive values represent shrub and grassland (approximately 0.2 to 0.4), values from 0.1 upwards represent very low amounts of grassy vegetation] . Figure 1 shows that the acquired data (by Remote Sensing techniques from satellite imagery (MODIS)) can be used to estimate the magnitude of the drought. The plot is indicating that the vegetation index (Y-axis) has been reduced dramatically from 2004 onward (red is the average of all pixels in the grid having an acceptable quality, blue indicates the value for the center pixel, which for MODIS is 5.5 ha, having acceptable quality). On the ground, it means that the farmers were facing a new challenge. The locally collected statistics from other layers of data presented that the increasing trend from 2001 to 2004, was due to the multiplication of deep water wells. That remedy did not work for further years (beyond 2004), so even where the crop pattern did change and some farmers were able to switch from cereal growing to pistachio growing , they faced in the long run a new challenge as to water availability. Sarvestan in the drought episodes Page 3 The new problem led to lower level of water resources in the whole Sarvestan plain. Water became even scarce for the newly established pistachio orchards. And the older orchards, like in Mr. Mahani’s case, faced the problem too. Episode 3 (surviving drought through management) The new problem needed a new approach for adaptation (e.g. Stigter, 2008). The first solution which was practiced by Mr. Mahani and other leading pistachio growers, was to buy the water from neighbor farmers who used to be crop growers. The economic privilege of the pistachio made this possible for some growing seasons. The persisting drought outperformed this solution very soon, when there was no water remaining to be traded. The next step to survive and keep the pistachio trees alive and productive was to improve the irrigation system and its water source, while keeping a good water management as the key point. The irrigation channels were covered and the water wells went through a reconstruction. The drops became costly by all its meanings. In order to have a better operational decision support and management practice, Mr. Mahani installed a complete “Automatic Weather Station” (Fig. 2) and started practicing “Agro-meteorology” (see also Winarto et al., 2013). The new tools have helped Mr. Mahani to monitor the Soil Moisture Level in a way that he is scheduling the irrigation time or “When to start and stop“ irrigation, based on the soil moisture levels. With this method, water can be saved and will not run off the trees access. Fig. 3 shows the irrigations start at the peak of the plot and the pressure on the trees not excceding the tolrance level for pistachio trees (120 Centibar) and the mosture level maintained in the interval of irrgation on a constant level of about 40 centibar . Another measure which was adapted to save water is to increase the “water holding capacity” of the soil by adding organic materials to it. The data from the Soil sensors showed over time indicated that with Soil moisture monitoring and organic material increase, Mr. Mahani was able to increase the irrigation cycle from 30-40 days to 50 days. Sarvestan in the drought episodes Page 4 Fig. 2 Mr. Mahani and his Automatic Weather Station Sarvestan in the drought episodes Page 5 Fig. 3 Irrigation and soil moisture Fig. 4 Irrigation and Evapotranspiration Sarvestan in the drought episodes Page 6 The new tool measured also Evapotranspiration (ET). By combining the amount of ET, which somehow is the net amount of the required water, he can estimate the actual water requirement of the trees (Fig. 4). He reached a personal and customized “irrigation schedule” over four years of practicing agricultural meteorology. The results The result of response farming and agro-meteorology combined with a proper decision support system, is that the 50 hectares of pistachio trees are in good productivity, even while the drought condition persists. This achievement is confirmed by the latest Satellite remote sensing data for “NDVI.” This index can be used to estimate the ground vegetation amount (Fig.1). The red pixels of Fig. 5, in the middle of the “NDVI” map, indicate the pistachio orchard in the summer of 2014. The map represents a rectangular 7km by 7km area in the vicinity and around the Mr. Mahanis orchard. The “red color” represents the maximum vegetation while pale blue shows the lowest ground vegetation cover. The map of Fig. 5 shows the average vegetation index for 16 days in Aug 2014. Figs. 6 and 7 picture other phases of his fields. It is a proof that Mr. Mahani has been successful in adapting to climate change so far. He applied within his possibilities several response farming approaches with agrometeorology and reconstruction to adapt to the drought condition in Sravestan plain. References Kees Stigter, Yunita T. Winarto, Emmanuel Ofori, Gugulethu Zuma-Netshiukhwi, Durton Nanja and Sue Walker, 2013. Extension agrometeorology as the answer to stakeholder realities: Response farming and the consequences of climate change. Special Issue on Agrometeorology: From Scientific Analysis to Operational Application. Atmosphere 4 (3): 237-253. Kees Stigter, 2008. Agrometeorological services under a changing climate: old wine in new bags. WMO-Bulletin 57(2): 114-117. Y.T. Winarto, K. Stigter, B. Dwisatrio, M. Nurhaga, and A. Bowolaksono, 2013. Agrometeorological Learning Increasing Farmers' Knowledge in Coping with Climate Change and Unusual Risks. SouthEast Asian Studies (Kyoto University, Japan), 2(2): 323-349. (Edited for INSAM by Kees Stigter) Sarvestan in the drought episodes Page 7 Fig. 5 Avarage 16 days of Vegitation index for Sarvestan plain ( 7x7) kms Sarvestan in the drought episodes Page 8 Fig. 6 Mr. Mahani’s pistachio orchard in 2014 ( the only left “green” sign in the plain) Fig. 7 Mr. Mahani’s orchard in 2006 (still cereals growing practiced in Sarvestan area) Sarvestan in the drought episodes Page 9 .