Water Harvesting for Improved Water Productivity in Dry Environments of the Mediterranean Region Case study: Pistachio in Turkey

Abstract

Low rainfall, water scarcity and land degradation severely intimidate the production capacities of the rangelands in the arid environments. Water harvesting focuses on improving the productive use of rainwater on the local scale (field to subcatchment scale) before the runoff water leaves the geographical unit in question. The aim is to mitigate the effects of temporal water shortages to cover both domestic and agricultural needs. This paper provides a review on water harvesting techniques focusing on microcatchment methods, and information on performance of a small-basin water harvesting system (negarim) under a typical arid environment in Turkey as a case study. In the negarim case study, we analysed rainfall, runoff, catchment area, soil water storage and crop evapotranspiration. The microcatchment area (36 m 2 ) included five surface treatment methods (natural, plastic cover, stone cover, hay cover and compaction), which were studied in a pistachio plantation by monitoring soil water balance in the root zone. The overall efficiency of the water harvesting system was determined as the ratio of the amount of water stored and used by the crop to the amount of rainfall received in the catchment area. It was demonstrated that the overall efficiency of the system varied from 2.9 % to 79 % depending on the surface treatments and the root zone capacity. Plastic cover had the greatest efficiency. Gains in runoff improvement were lost when the soil moisture in the cultivated area was near field capacity. Surface treatments had a significant effect on plant height and stem diameter. Plant height with different treatments was 158 cm with plastic cover, 128 cm with surface compaction, 121 cm with hay cover, 117 cm with stone cover and 102 cm of control. Among the surface treatments, plastic cover was superior to the other treatments on plant growth, but the use of plastic may cause environmental problems.

Promising Water Management Strategies for Arid and Semiarid Environments

“…The size of the runoff production area directly determines the total amount of runoff water that can be stored in the pit together with soil and rainfall characteristics, topography, etc. [25]. Reported sizes of a single plot are 100-250 m 2 in Israel, 250-400 m 2 in India, and 1000 m 2 in Mali [16].…”

A review of crop water productivity in the Mediterranean basin under a changing climate: Wheat and barley as test cases

“…In addition to deficit irrigation, catchment water harvesting can also supplement a water‐scarce rainfed system. While there are many options, including plastic cover harvesting, and rye, stone and surface compaction, unfortunately these are not all reliable in erratic rainy conditions, since they require extensive care in terms of overflow during extreme precipitation and can be a source of water pollution as well (Yazar et al, 2014). Similarly, soil management practices such as shallow tillage are useful, but they also depend on rainfall frequency during the growing season (Ozpinar, 2006).…”

Effect of the Gravel Filters and Plastic Cover on Improving Water Infiltration Process and Increasing Moisture Storage of Rainwater Harvesting Systems in Sloping Lands

“…Establishment of rainwater catchment systems to collect su cient rainwater from the catchment area and optimal use of low daily rainfall to facilitate vegetation can be a solution to deal with stress and permanent water shortage crisis, especially in arid and semi-arid regions ( Kahinda and Taigbenu., 2011; Noori and Zare Chahouki., 2018; Yazar et al 2014 ). Reservoir surface systems, in addition to their important role in the establishment and development of vegetation, control and store runoff on sloping surfaces, Reservoir surface systems penetration into the soil, increase moisture storage in soil pro les, and reduce evaporation from the soil surface in watersheds ( Shaxson and Barber., 2003).…”