The soil degradation caused by the use of low-quality waters in agriculture may be restricted with reorganization of irrigation practices. Therefore, a 2-year study was conducted to determine the changes in chemical and biological properties of soil layers of 0–30, 30–60, and 60–90 cm of a tomato field that was irrigated by recycled municipal wastewater with different drip practices (full, DI: deficit irrigation, and PRD: partial root-zone drying irrigation). The study results showed that the soil electrical conductivity (EC) and exchangeable sodium percentage (ESP) values after the experiment were quite low considering the problematic levels (>4 dS/m for EC, and >15% for ESP), and the organic matter content did not change significantly. The highest N, P₂O₅, and K₂O concentrations were determined in 0–30 cm soil layer for fully irrigated with wastewater, whereas the PRD and DI treatments irrigated with 50% water saving resulted the lowest soil fertility. Wastewater treatment also increased concentrations of micro- and trace minerals, but the toxic element concentrations were in safe limits considering the FAO/WHO and national standards. In this 2-year study, it can be mentioned that treated wastewater applications increase soil fertility owing to the increase in macro and micronutrients. It may be suggested that wastewater treated with PRD and DI applications can be used in case of water shortages.

The present study aimed to determine the total and net erosion in the Capakcur watershed, which has a high erosion risk. Accordingly, annual soil loss in the Capakcur watershed was estimated using RUSLE method. Net erosion was determined directly by measuring the monthly flow rate and sediment concentrations of the Capakcur stream, which originated from the Capakcur watershed and flowed into the Murat River throughout 2019. Estimated soil loss in the Capakcur watershed was 96916.20 ton yr-1, and the amount of soil transported from the Capakcur stream was 68656.09 ton yr-1. Sediment delivery ratio (SDR) was calculated as 0.78. This ratio was well above the average SDR of Turkey (0.23). Topographic factors such as slope length and degree, rainfall, and low vegetation cover ratio in the watershed are the main causes of the high SDR. Due to the high SDR, the fertile surface soil layers of lands in the basin are carried to the streams. This causes both decrease in fertility in soils and pollution of the limited freshwater resources. In order to improve vegetation and management practices in the watershed, soil protection practices such as afforestation and terraces, wire cages and stone walls in gullies should be increased.

Intensive farming applications have been increasingly employed to balance the increasing world population and decreasing farming lands in the last half-century. The main purpose of these efforts is to obtain greater amounts of yield per area using modern agricultural methods. However, uncontrolled intensive farming applications (fertilization, irrigation, disinfection, etc.) disturb certain physical, chemical, and biological properties of soils. Especially the uncontrolled chemical fertilization applications increase the heavy metal concentrations in farming lands. The study compares certain properties of the soils from an active farming land (A-FL) in which intensive farming activities have been carried out since 1996 to those of the soils from a passive farming land (P-FL) with no farming activities. For this purpose, the study examines the changes caused by 25-year-long agricultural activities in the soils. The results revealed that the soils from the A-FL had higher levels of pH, electrical conductivity (EC), lime, nitrogen (N), phosphorus (P), potassium (K), arsenic (As), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn) than the soils from the P-FL. The negative impact of intensive agricultural activities on the soils is of great importance in terms of soil management and food safety. The uncontrolled agricultural applications indirectly and negatively affect human and animal health worldwide.

Harran ovasının güneydoğusunda GAP projesi kapsamında sulanmayan alanların çoğu yeraltı suları ile sulanmaktadır. Bu çalışmanın amacı Şanlıurfa ili Harran Ovasının güneydoğusunda Ohali köyü tarım alanlarında faaliyette olan 13 adet yeraltı sulama suyu kaynağının, bazı kalite özellikleri ile sulama açısından öneminin belirlenmesidir. Bu bağlamda13 adet yeraltı sondaj kuyusuna ait sular analiz edilerek sulama suyu kalitesi bakımından incelenmiştir. Analiz sonuçlarına göre su örneklerinin elektriksel iletkenlik değeri 1127- 4090 µS/cm arasında ölçülmüştür. Sulama sularının SAR değeri 1.05- 3.41 arasında, %Na değeri ise %16,2-%31,8 arasında bulunmuştur. Dört farklı sınıflandırma sistemine göre yapılan değerlendirmede genel olarak 6, 7, 8 ve 9 nolu sular bütün sınıflama sistemlerinde kalite olarak en kötü sular olarak belirlenmiştir. Bu sular sulama suyu olarak “uygun değil” olarak nitelendirilmiştir. Bölgede pamuk ve mısır gibi bitki su tüketimi yüksek olan bitkilerin tarımının yapıldığı göz önünde bulundurulduğunda, gerekli önlemler alınmadığı takdirde toprakta tuzluluğun artacağı ve verim kayıpların çok fazla olacağı ön görülmektedir. Çeşitli nedenlerle GAP sulama projesi kapsamında sulanamayan bu alanların bir an önce temiz su ile sulanması zorunludur. Bununla birlikte bölgede uygun bir drenaj sistemin tesis edilmesi gereklidir.

In this study physical (bulk density, particle density, porosity, wet aggregate stability) and hydraulic properties (field capacity, wilting point, available water content, infiltration) of the soil did not change significantly under different irrigation practices. However, the porosity, available water content, and infiltration improved partly under partial root-zone drying practice with 50% water shortage. Wet aggregate stability in surface soil increased significantly with wastewater treatment. Wastewater reduced the stable infiltration rate significantly as well. Although the physical and hydraulic properties improved when compared with the pre-planting values, the wastewater treatment could not provide sustainable important effects in a short-time period.