Engin YURTSEVEN, Sertan AVCI, Hasan Sabri ÖZTÜRK

Mass balance criteria in soil salinity management: Different irrigation water qualities and leaching ratio

Kurak ve yarı-kurak alanlarda toprakta biriken fazla tuzlar yaygın bir sorun olarak karşımıza çıkmaktadır. Tarım alanlarında tuzlulaşmanın meydana geldiği temel ortam sulanan alanlardır. Bu çalışmada, farklı sulama suyu tuzluluğu ve yıkama oranlarının toprak profilindeki tuz dengesine olan etkileri, yonca (Medicago sativa L.) yetiştirilen PVC kolonlarda (115 cm uzunluğunda ve 40 cm çapında) incelenmiştir. Çalışmada 3 sulama suyu tuzluluğu (0.25, 1.5 ve 3 dS m-1 sırasıyla S1, S2, and S3) ve 4 yıkama oranı (gereğinden % 10, 20, 35 ve 50 daha fazla sulama suyu) konuları 3 tekrarlamalı olarak tesadüf parsellerinde faktöriyel deneme şeklinde denenmiştir. Profildeki tuz dengesi, sulama suyu ile sağlanan toplam tuz miktarından, drenaj suyu ile dışarı atılan miktarın farkından hesaplanmıştır. Sulama suyunun tuz içeriği artıkça, fazla miktardaki Cl- nedeniyle topraktan SO42- yıkanması artmış ancak HCO3- artmamıştır. Çözünebilir anyonlardan SO42- profilden yıkanırken Cl-, sulama suyu tuzluluğunun artmasına bağlı olarak birikmiştir. Yıkama oranının artması toprak profildeki Cl- yıkanmasına neden olmuştur. Toplam tuz dengesi, topraktaki başat katyonlar için de (Ca2+, Mg2+, ve Na+) sulama suyunun tuz konsantrasyonu ve yıkama oranına göre değerlendirilmiştir. Toprak profilindeki Ca2+ miktarı sulama suyu tuzluluğu ve yıkama oranlarına bağlı olarak artma gösterirken, Mg2+ ve Na+ dengesi önemli bir şekilde azalmıştır. Bu Ca2+ ‘un Na+’a göre toprakta daha fazla tutulması nedeniyledir. Genelde yıkama oranlarının tuz dengesi üzerine etkisi iyonlara bağlı olarak değişiklik göstermektedir.

Toprak tuzluluğu yönetiminde tuz dengesi kavramı: Farklı sulama suyu tuzluluğu ve yıkama oranı

The accumulation of excess soluble salts in the root zone of arid and semiarid irrigated soils is a widespread problem that seriously affects crop productivity. The cultivated soil profile under irrigation is the main media in which the salinization occurs. In this study, the effects of different irrigation water salinity and leaching ratio on soil profile salt mass balance changes were investigated in alfalfa (Medicago sativa L.) cultivated PVC lysimeters (115 cm in height and 40 cm diameter). Three irrigation water salinity (S1, S2, and S3, 0.25, 1.5 and 3.0 dS m-1, respectively) and four leaching ratios, LF, (10%, 20%, 35% and 50% more water than ET) levels were used in a fully randomized factorial design experiment with three replications. The total salt mass balance was calculated from the subtraction of total salt mass concentration supplied with irrigation water and total salt mass concentration washed out with the drainage water. When the salinity content of irrigation water increased leaching of SO42- and Cl- accumulation in the soil increased. Increase in the leaching ratio (LF) caused increase in the leaching of Cl- through the soil profile. The major cations, Ca2+, Mg2+, and Na+, in the soil were also evaluated for their total mass concentrations regarding salinity content of irrigation water and LF. Ca2+ concentration in the soil profile increased with salinity level and the leaching ratio, whereas Mg2+ and Na+ mass concentrations decreased considerably. This is due to the high Ca2+ adsorption in the soil than that of Na+. The effect of LF on the ion mass accumulation or leaching varied depending on the ion type.

PDF

___

Al-Absi K M, Al-Nasir F M & Mahadeen A Y (2009). Mineral content of three olive cultivars irrigated with treated industrial wastewater. Agricultural Water Management 96: 616–626
Corwin D L, Rhoades, J.D. & Simunek J (2007). Leaching requirement for soil salinity control: Steady-state versus transient models. Agricultural Water Management 90: 165–180
Hutson A C & Ickert R A (2012). Sustainability in water supply. In: World Environmental and Water Resources Congress 2012: Crossing Boundaries, ASCE, pp. 2856-2872
Islam Md Z (1993). Leaching Effect of Saline Drainage Water on Exchangeable Cations in Soil. Journal of Irrigation, Engineering and Rural Planning 24: 4-18
Jalali M & Rowell D L (2003). The role of calcite and gypsum in the leaching of potassium in a sandy soil. Experimental Agriculture 39: 379-394
Kijne J W, Prathapar S A, Wopereis M C S & Sahrawat K L (1998). How to Manage Salinity in Irrigated Lands: A Selective Review with Particular Reference to Irrigation in Developing Countries. SWIM Paper 2. Colombo, Sri Lanka: International Irrigation Management Institute, Sri Lanka
Oster J D, Letey J, Vaughan P, Wu L & Qadir M (2012). Comparison of transient state models that include salinity and matric stress effects on plant yield. Agricultural Water Management 103:167–175
Öztürk H S & Özkan İ (2002). Solute movement in large soil columns during different ponded infiltration. Australian Journal of Agricultural Research 53: 183- 189
Rhoades J D (1974). Drainage for salinity control. In: van Schilfgaarde J (Ed.), Drainage for Agriculture. Agronomy Monograph No. 17. SSSA, Madison, WI, pp. 433–461
Rhoades J D & Loveday J (1990). Salinity in irrigated agriculture. In: Stewart B A & Nielsen D R (Eds.), Irrigation of Agricultural Crops. Agronomy Monograph No. 30. SSSA, Madison, WI, pp. 1089– 1142
Richards L A (1954). Diagnosis and Improvement of Saline and Alkali Soils. U.S. Dept. Agriculture, Handbook 60. U.S. Government Printing Office, Washington
Siczek A, Kotowska U, Lipiec J & Nosalewiczl A (2008). Leaching of potassium, magnesium, manganese and iron in relation to porosity of tilled and orchard loamy soil. Acta Agriculturae Scandinavica Section B- Soil and Plant Science 58: 60-65
Skaggs T H, Poss J A, Shouse P J & Grieve C M (2006). Irrigating forage crops with saline waters: 1. Volumetric lysimeter studies. Vadose Zone Journal 5: 815–823
Yıldız M & Terzi H (2011). Türkiye’de Ekimi Yapılan Bazı Arpa Çeşitlerinde Erken Fide Evresi Tuz Toleransının Belirlenmesi. Tarım Bilimleri Dergisi 17(1): 1-9
Yurtseven E, Avcı S, Öztürk H S, Altınok S & Selenay M F (2012). Drainage water quality management: impact of different irrigation water quality and leaching fractions on drainage water salinity. In: Proceedings of the VIII. International Soil Science Congress “Land Degradation and Challenges in Sustainable Soil Management” 15–17 May, İzmir, Turkey
Zhong H (2011). Salt mass balance study and plant physiological responses for an enhanced salt phytoremediation system. Master Thesis (Unpublished), Waterloo University, Ontario, Canada