The possibility of improving forest plantations in dry lands through spate irrigation: A case study

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1 Scholarly Journal of Agricultural Science Vol. 3(10), pp October, 2013 Available online at ISSN Scholarly-Journals Full Length Research Paper The possibility of improving forest plantations in dry lands through spate irrigation: A case study Kambiz Taheri Abkenar Faculty of Natural Resources, University of Guilan, Rasht, Iran. taherikambiz@guilan.ac.ir. Accepted 30 h August, 2013 The Kowsar Floodwater Spreading, Aquifer Management, located in the Gareh Bygone Plain at 1140 m above mean sea level with arid climatic conditions, 190 km southeast of Shiraz, Iran was established in Thirteen spate irrigation systems covering 2445 ha were designed and constructed during the 1983 to 2003 period for the artificial recharge of groundwater (ARG). Exotic trees, mainly Eucalyptus camaldulensis Dehnh and Acacia salicina Lindl., covered about 100 ha of the systems. The eucalypt wood yield ranges from 1.37 to 4.04 m³/ha year depending on the location in the ARG systems, with the overall mean yield of 2.19 m³/ha year. This indicates the unsuitability of this species for afforestation in this area. As E. camaldulensis is a prodigious water consumer, and planting this tree negates the principal objective of such projects, I propose replacing it with less water demanding, deep-rooted indigenous trees if the main objective is wood production. A methodical species trial is the first step in this undertaking. Key words: Forest plantation, floodwater, Aquifer management, E. camaldulensis. INTRODUCTION The Islamic Republic of Iran is called the land of floods and droughts due to the frequent flooding even during severe droughts. Floodwater, rather than causing death and destruction, should be used to ameliorate the effects of droughts (Kowsar, 2003). The fate of the abandoned land in arid zones is desertification. Provision of plant water requirements should precede the biological rehabilitation of such areas. Most of the extremely poor and hungry people of the world live in marginal dry lands. Application of the ARG techniques in a framework of an integrated approach facilitates their well-being (Bouwer, 2002). The comparison of on and off-stream facilities for the ARG shows that FWS is the most cost-effective method for supplying water demand in marginal dry lands. Floodwater spreading systems have the potential to be used in an integrated and multipurpose approach (Sharifi, 2005). Floodwater spreading (FWS) systems facilitate spate irrigation of the planted sites, as well as, the artificial recharge of groundwater (ARG) if the land is underlain with coarse-grained alluvium (Nejabat, 2003). Planting sedimentation basins and recharge ponds of the ARG systems to trees or other crops is implemented to convert some of the water wasted in evaporation to transpiration. Therefore, FWS has the potential to make significant impacts on the well-being of the arid land dwellers (Kowsar, 2007). The Kowsar Floodwater Spreading, Aquifer Management, Training and Extension Station, located in the Gareh Bygone Plain at 1140 m above mean sea level with arid climatic conditions, 190 km southeast of Shiraz, Iran was established in 1982 (Figure 1). Results of an 18-year study in the Gareh Bygone Plain, a sandy desert, has proved that spate irrigation of a denuded rangeland significantly increases its productivity (Mesbah and Kowsar, 2010). Deposition of nutritious suspended load has improved the available water holding capacity and fertility, thus the productivity of this sandy soil (Rahbar and Kowsar, 2008). Based on some long-term studies performed by the Research Institute of Forests and Rangelands, Eucalyptus camaldulensis, Eucalyptus microtheca, Eucalyptus gillii, Eucalyptus oleosa and Eucalyptus fruticetorum and also Acacia salicina, Acacia victoriae, Acacia saligna and Acacia cyanophylla were planted in the ARG systems from 1983 to 1995 in the adaptation

2 Abkenar 417 Figure 1. Gareh Bygone plain before FWS (1982). trials in the GBP (Kowsar, 1993, 1996; Mortazavi, 1994). The expected functions of these trees were protection against wind and water erosion, and amelioration of the harsh environment. Adelpour and Ghahari (2007) confirmed the positive effects of the planted trees on diminishing sand storms and water erosion in the GBP. As E. camaldulensis has shown the best performance amongst the tried tree species (honey production at 15.2 kg per year in each colony (Eilami, 2004); carbon sequestration at t/ha per year (Bordbar, 2005); pharmaceutical properties and wood yield, etc). This study was performed to assess the effects of spate irrigation on the afforested E. camaldulensis Dehnh with the following objectives in mind: - Can application of floodwater spreading systems develop afforestation in arid zone? - What is the rate of spate-irrigated wood yield as compared to natural forests? MATERIALS AND METHODS The Gareh Bygone Plain is located in southeast of the Fasa city in the Province of Fars (53 36 to E, to N, 1140 m above mean sea level (Figure 2). Mean slope of basin is 38.03%. Gareh baygon weathering is affected by the two currents Mediterranean and India Ocean local storms in summer after having the flooding rains (Table 1). These rains are from a kind of convection and affected by the temporary India rains (Mesbah, 1387). For analysis of weathering, regional study and derived weathering parameters used in Gareh baygon evaporation station static (12 years: 1375 to 1376 to 1386 to 1387) that is located in 45 km south-eastern of Fasa city (depended on Fars water organization). Mean of frozen days in Gareh baygon is 26 days (kowsar, 1992). According to modified De matron method; the studied basin is located in cold desert arid, mild desert arid, cold semi-arid and mild semi-arid classes of climates. Based on some research and recommendations of Research Institute of Forests and Rangelands, several species of Eucalyptus and acacia were cultivated since 1983 for adaptation and had shown good growth under FWS in western of Fars province (Kowsar, 1993, 1996). Initially, in 1985, some species of Eucalyptus and Acacia were planted as follow: E. camaldulensis, E. microtheca, E. gillii, Acacia salicina, A. victoriae, A. saligna, A. cyanophylla, E. oleosa and E. fruticetorum. The E. camaldulensis was selected to investigate and operate statistics for four years (from October, 2004 to December, 2007; (Figure 3). Some quantitative indices

3 Scholarly J. Agric. Sci. 418 Figure 2. Location map of Gareh Bygone plain. Table 1. Weathering parameters in regional study (derived from Gareh bygone evaporation station). Row Parameter Value 1 Mean of annual precipitation mm 2 Mean of annual absolute maximum temperature C 3 Mean of annual absolute minimum temperature C 4 Mean of annual temperature C Figure 3. Planted area under spread flood.

4 Abkenar 419 Figure 4. DBH measuring. Figure 5. Total height measuring. (total height and D.B.H) of them were measured and recorded twice per year (seven times in total). The trees were grouped as follows: 1. Old afforestation (from1985) at Bisheh Zard 4 (BZ4), Rahim Abad 2 (RA2) and control basins. 2. New aforestaion (from1995) at Bisheh zard1 (BZ1). 3. For sampling, 30 trees were selected and measured. The diameter at breast height (from 1.3 m from ground level) for each tree using a caliper ruler (according cm) was measured and recorded (Figure 4). Total height of all trees was measured using clinometers (Figure 5).

5 Scholarly J. Agric. Sci. 420 Figure 6. Stand volume variation in study period. Table 2. Mean stand volume of sample areas. Sample areas Differences Bz Bz Bz G G G Ra NF The mean of beginning and end of the investigation period for each plots were compared through F test method. RESULTS AND DISCUSSION The wood yield of old afforested area (planted in 1985) after 23 years was m 3 / ha which produced (at mean) 2.2 m 3 / ha per year. Wood production in the new afforested area (young stands trees planted in 1996) at the end of 12 year period was 33/14 m 3 / ha, that is, approximately 1.19 m 3 / ha per year (Table 2 and Figure 6). The carbon sequestration by Eucalyptus camaldulensis Dehnh was evaluated and t/ha per year in relatively fertile habitats and t/ha per year in weak habitats was reported. Remarkable growth of trees in first bond G1 resulted from that area of flooding in all of flood events. The survival rate of E. camaldulensis in the study area was determined 96.43%. As the mean of stem wood production of the 5-year old E. camaldulensis trees in the G1 basin had been 7.8 cubic meters (7000 kg) per ha per year (Mortazavi et al., 1989), these trees have maintained their growth potential. The reason for the high yield in the G1 basin relative to others is the very high volume of floodwater it has received. The soil profile was wet to a depth of 5 meters at planting time; the seedlings received heavy flooding in March, July, August and December of Moreover, they were irrigated for about 2 months in early Although we have not measured the volume of water that each basin receives, our observations confirm the positive relationship of growth with water availability. It is interesting to note that wood yield in this desert is higher than those in areas with more annual rainfall, even higher than that of the forests in Australia, its land of origin. Based on this study, afforestation using spate irrigation

6 Abkenar 421 Figure 7. Gareh Bygone plain after FWS (2007). (FWS) is possible in dry lands (Figure 7). As E. camaldulensis is a prodigious water consumer, and planting this tree negates the principal objective of such projects, I propose replacing it with less water demanding, deep-rooted indigenous trees if the main objective is wood production. A methodical species trial is the first step in this undertaking. However, a thriving bee-keeping enterprise (Eilami, 2004), and leaf production for medicine and browsing by livestock cannot be ignored. Moreover, the area attracts many eco-tourists, particularly during the Iranian New Year holidays in March and April. REFERENCES Bordbar, K. and Mortazavi, M. (2005). Carbon sequestration potential of Eucalyptus camaldulensis Dehn. and Acacia salicina Lindl. plantation in floodwater spreaders of the sandy desert of Gareh Bygone. Pajouhesh and Sazandegi, 70, Bouwer, H. (2002):Artificial recharge of groundwater, hydrogeology and engineering. Hydrol. J. 10, Eilami, B. (2004). A study on productive characteristics of honey bee colonies (Apis mellifera L.) in the Eucalyptus jungle of Fars province (Kowsar floodwater spreading station). Pajouhesh and Sazandegi Kowsar, A. (1995). An Introduction to Flood Mitigation and Optimization of Floodwater Utilization: Flood Irrigation, the Artificial Recharge of Groundwater, Small Earth Dams. Research Institute of Forest and Rangelands, Tehran, I. R. Iran. Kowsar, A. (1998).Floodwater: the softest hardware. Tiempo, 28: Kowsar, A. (2003). Abkhandari (Aquifer Management): A Green Path to the Sustainable Development of Marginal Drylands. United Nation University Annual Report. Tokyo. Japan. Kowsar, A. (2006). Aquitopia Gareh Bygone Plain subproject. 4th International SUMAMAD Project Workshop, 26 Jan. -1 Feb Islamabad, Pakistan. Kowsar, A. (2008). Desertification control through floodwater harvesting: The current state of know-how. In "Man and Biosphere series"(eds.: Lee C., Schaaf T.) The Future of Drylands. International Scientific Conference on Desertification and Drylands Research. Tunis, Tunisia, June UNESCO Publishing, Paris. pp Kowsar, A., Mortazavi, M. and Niazi, A.M. (1996). Eight- year performance of Eucalyptus camaldulensis in water spreaders in a sandy desert. Desertification Control Bulletin (UNEP) 29: Mesbah, H. and Kowsar, A. (2010). Spate Irrigation of Rangelands, A Drought Mitigating Mechanism. In" Agricultural Production" (Ed.: Wager F). Nova Science Publishers, Inc. pp Mortazavi, M. and Kowsar, A. (1994). Adaptability trials of Eucalyptus and Acacia species in a floodwater spreader in a sandy desert. Proceeding of 4th International Conference on Desert Development. Negahdarsaber, M. and Mesbah, H. (2009). The possibility of producing wood in dry lands through spate irrigation: A case study. First national workshop on sustainable management of marginal dry lands (SUMAMAD Phase 2). Nejabat, M. (2003). Effect of the Floodwater Spreading on Desertification Control using Remote Sensing. Proceeding of Seventh International Conference on Dryland Development: Sustainable Development of Dry Lands in the 21 st Century, 6-9 October Tehran, I. R. Iran. Rahbar, G.H. and Kowsar, A. (2004). Floodwater irrigation in southeast of Fars province, Iran, Proceeding of CIGR International Conference, October 11 14, 2004, Beijing, China. Sharifi, F. (2005). Traditional and modern techniques in rainwater harvesting and artificial recharge, modeling and design consideration in arid and semi-arid regions. Regional Workshop on Management of Artificial Recharge and Rainwater Harvesting. Lahore, April 25-May 2, Pakistan.