Talip Tunc

Bacterial application increased the flow rate of CaCO3-clogged emitters of drip irrigation system

CaCO(3) is one of the most common emitter clogging factors among chemical precipitates in drip irrigation systems. Continuous acid application as a classical approach to prevent CaCO(3) clogging can be tricky, expensive and hazardous for soil. In order to develop an environmentally friendly method to address the problem, two bacterial strains, one renowned as a PGPR and the other having extensive CaCO(3) dissolving capacity, were used in treatments of artificially clogged drip irrigation emitters. Results showed the flow rates of clogged emitters significantly increased in drip lines which were treated with bacterial suspensions but no increase was observed in control drip lines which were treated with sterile nutrient broth. Furthermore, scanning electron and florescence microscopies were used to examine residual CaCO(3) precipitates. Thus, in consideration of its extensively studied PGPR characteristics, microbial treatment with Bacillus subtilis OSU-142 was shown to be promising for field applications as a novel and environmentally friendly treatment for clogged emitters of drip irrigation systems.

Determining Crop and Pan Coefficients for Cauliflower and Red Cabbage Crops Under Cool Season Semiarid Climatic Conditions

Abstract The aim of this study was to estimate the evapotranspiration of cauliflower and red cabbage crops grown under cool season semiarid climatic conditions from Class A pan evaporation. Actual evapotranspiration ( ET c ) of cauliflower and red cabbage crops was calculated according to the water balance approach. Reference evapotranspiration ( ET o ) was calculated with FAO Penman-Monteith equation. Pan evaporation ( E pan ) was measured by using Class A pan. Seasonal ET c was determined as 475 mm for cauliflower and 556 mm for red cabbage. Seasonal pan coefficient ( k p = ET o / E pan ) was determined as 0.82, and the seasonal crop coefficient ( k c = ET c / ET o ) was determined as 0.84 for cauliflower and 0.83 for red cabbage. So the evapotranspiration of cauliflower and red cabbage crops was estimated as 70% Class A pan evaporation.

Evaluation of CaCO3 clogging in emitters with magnetized saline waters

Abstract High water application uniformity is essential for an effective irrigation. Clogging of emitters in drip irrigation systems is one of the most important factors decreasing uniformity. In this study, the possible effect of magnetization of water on chemical clogging of dripline emitters was investigated. Separate experiments were conducted with three different saline waters (W-1: 0.314 dS m−1, W-2: 0.665 dS m−1, W-3: 0.937 dS m−1) having a high pH and a positive Langelier saturation index (LSI). Discharge rates, electrical conductivity (EC) and pH’s of discharge water from emitters in driplines were measured. Uniformity of driplines was evaluated by using the statistical uniformity coeffi cient (Uc ) and the emission uniformity coeffi cient (Eu ). The pH and EC values of discharge water from emitters in driplines were found to be slightly lower when operated with magnetized water. However, discharge rates under non-magnetized water were lower than those of magnetized water. Magnetic effect was obs...

Yield and Heavy Metal Content of Wastewater-Irrigated Cauliflower and Soil Chemical Properties

ABSTRACT A two-year field study was conducted to determine the effects on the growth, yield, heavy metal content, and water use of cauliflowers and on the soil chemical properties of irrigation with reclaimed urban wastewaters (filtered, aerated, diluted) by comparing with fresh water under semi-arid climate conditions. Cauliflower curd yield, water use efficiency, and heavy metal contents were found to be the highest in the filtered wastewater application. Cadmium (Cd) content was just over the critical level for human health. Filtered and aerated wastewater applications created higher soil salinity, organic matter, and total nitrogen (N), dipotassium oxide (K2O), and phosphorus pentoxide (P2O5) contents. Copper (Cu), iron (Fe), and manganese (Mn) contents in the surface soil were also found to be significantly higher. Treated-wastewater irrigation could increase cauliflower yield and water productivity. However, higher heavy metal contaminations under these conditions may increase health risks. Therefore, the diluted wastewater application may be preferred, but it must be utilized while taking human health into account.