Effects of drip-irrigation regimes with saline water on pepper productivity and soil salinity under greenhouse conditions

The aim of this study was to investigate the response of sweet pepper (Capsicum annuum L.) to saline irrigation water and various irrigation regimes. The experiments were conducted in a greenhouse with two sweet pepper varieties (ONUR F1 and ADA F1) over two cropping seasons: spring and autumn on the Mediterranean coast at Antalya, Turkey. The irrigation regimes comprised four levels of Class A pan-evaporation and were applied using a drip irrigation system when evaporation reached a target value of around 10 mm. These four levels represented 0.50, 0.75, 1.00 and 1.25 of Class A pan-evaporation. In each irrigation regime the sweet pepper plants were exposed to four salinity treatments with electrical conductivities of 1.0, 2.5, 3.5 and 6.0 dS m−1 respectively. The study showed that both pepper varieties generally performed in a similar manner (except in terms of vegetative biomass production). The amount of salt accumulation within the root-zone was higher in spring compared to autumn; and therefore related to the total amount of irrigated water usage between seasons due to climatic variability. Increased salinity induced higher levels of salt accumulation within the pepper plant’s root-zone, while an increased amount of saline irrigation water increased the size of the affected layer within the root-zone. Overall, an increased level of salinity alongside increased irrigation considerably depressed both vegetative growth and yield. Higher irrigation water productivities were attained with a regime comprising 0.50 of Class A pan-evaporation and which appeared to fulfil crop water requirements. It was found that sweet pepper varieties ONUR F1 and ADA F1 are moderately sensitive to salinity with a threshold value of 1.43 dS m−1 and a decreasing slope value of 11.1%. Although both seasons revealed a single salinity response function, there were considerable differences in the actual fresh pepper yield. This study demonstrates that for pepper crops irrigated with saline water (or grown on salt-affected soils), pepper growers must consider the salinity response function and seasonal productivity alongside an appropriate irrigation regime

Effect of Micro-catchment Water Harvesting on Soil-water Storage and Shrub Establishment in the Arid Environment

ABSTRACT Potential of micro-catchment water harvesting (MCWH) to conserve soil-water and establish shrubs on a degraded land in an arid environment was studied. A research site was developed on 100 ha in Syrian rangelands having an average annual rainfall 117 mm. Contour ridges with 6 and 12 m spacing were built by using mechanized implements and 10,000 shrubs were planted with direct seeding and seedling methods. Rainfall, soil-water and shrub survival and growth parameters were measured. Results revealed that water at shrub location site was 1.2-4 times higher than the soil-water in micro-catchment area. Soilwater remained below wilting point during dry spells and increased after each runoff generating rainfall event. After 24-36 hours of rainfall, the soil-water was high in layers between 15 and 45 cm and low below 60 cm depth. Shrub survival rate was highest for Atriplex halimus (71%) followed by Salsola vermiculata (56%) and Atriplex leucuclada (31%). Efforts to raise shrubs by direct seeding method were not successful as only a few seeds germinated and none of them survived. Very low rainfall during second year (44 mm) contributed to low survival rate. In general, the shrub growth was slow but it was highest for A. halimus and lowest for S. vermiculata. The study showed that A. halimus due to its high survival and growth rate, is suitable for this environment

Introducing quinoa in Turkey:farmers perception in the region of Adana

In order to look for a more diverse and sustainable cropping system with high value crops in the Mediterranean region of Turkey, the drought and salt tolerant crop quinoa was analysed as an alternative to the current major crops, for instance wheat. This study investigates the conditions for growing quinoa in Adana, and how they are perceived among farmers in the region. A combination of qualitative and quantitative research was employed to group farmers into segments according to their willingness to adopt quinoa. Findings from this study indicate that farmers in Adana perceive quinoa as a crop likely to be adopted in their cropping system if they can gain market access with the new crop. Farmers’ previous knowledge regarding the crop, concerns about drought and salt risk and farm characteristics also appear to be determining the farmers’ attitude towards new crops

DETERMINATION OF EVAPORATION AND DRIFT LOSSES FROM SPRINKLER IRRIGATION SYSTEMS UNDER VARIOUS OPERATING AND CLIMATIC CONDITIONS

Quantitative determinations of evaporation and drift losses from sprinkler sprays were made under the different operating and climatic conditions at the University of Nebraska Field Laboratory at Mead, Nebraska. Droplet size distribution in drift was also evaluated under various wind conditions. The average evaporation losses determined by an electrical conductivity method, ranged from 1.5 to 16.8 percent of the total volume discharged by sprinklers. The results of the multiple regression analysis of the data indicated that average wind velocity and vapor pressure deficit were the most significant factors affecting the evaporation from the sprays. An exponential relationship between the evaporation loss and wind velocity was found. The relationship between the vapor pressure deficit and evaporation loss was also exponential. For the pressure levels used in this study, the operating pressure factor did not have a significant effect on evaporation from the sprays. A comparison of the evaporation losses estimated by various theoretical and experimental equations for a given set of operating and climatic conditions showed that experimentally obtained prediction equations estimate greater evaporation losses than the theoretical equations. Drift losses defined as the quantity of spray droplets passing through a plane perpendicular to the direction of wind a short distance downwind outside the sprinkler application pattern, ranged from 2.0 percent at a wind velocity of 2.68 m/s to 15.1 percent at a wind velocity of 6.71 m/s at an operating pressure of 310 kPa (45 psi) when the losses were measured at 21 m from the lateral. When the losses were determined at 26 m, the drift losses varied from 1.5 percent to 10.4 percent of the total volume discharged by the sprinklers. Drift losses increased in proportion to approximately the second power of the average wind velocity. Wind velocity is the predominant factor controlling the amount of drift from a given sprinkler system operated at a specified pressure. Drift losses decreased drastically with increasing distance from the lateral. Combined spray losses ranged from 1.8 to 29.0 percent of the total volume discharged by the sprinklers, when the losses due to wind drift at 21 m were considered in the estimation of the combined losses. When the drift losses at 26 m were considered, the combined losses varied from 1.7 to 22.9 percent. On the average, 47 percent of the total losses were due to drift for wind velocities greater than 4.0 m/s, and for wind velocities less than 4.0 m/s, the drift losses consisted of 25 percent of the total losses. In addition to spray loss determinations, an analysis of the droplet size distribution in the drift was made by applying the modified log-probability function called \u27Upper Limit Equation\u27 to the observed droplet size data. The results showed that distribution of droplets in the drift can be represented by the upper limit equation. Volume mean diameters, d(,50), and 95-percent sizes, d(,95), increased with increasing wind velocity

Determination of Crop Water Stress İndex (CWSI) and Irrigation Timing by Utilizing Infrared Thermometer Values on the First Corn Grown Under Çukurova Conditions

Bu çalışma, Çukurova koşullarında yetiştirilen I. ürün mısır bitkisinde infrared termometre (IRT) değerlerinden yararlanılarak bitki su stresi indeksini (CWSI) saptamak, bu indeksi kullanarak sulama zamanı ve mısır dane verimi ile CWSI arasındaki iliştiyi belirlemek amacıyla yürütülmüştür. Bu araştırmada farklı düzeylerdeki su stresi, her 10 günde bir 120 cm’lik toprak profilinde tüketilen suyun %100 (I100), %80 (I80), %40 (I40), %20 (I20) ve %0 (I0 )’ının tekrar uygulanması şeklinde oluşturulmuştur. Böylece 6 farklı düzeyde stres içeren sulama konusu meydana getirilmiştir. Araştırmada I100 konusuna denemenin birinci ve ikinci yılında sırasıyla toplam 752 ve 823 mm su uygulanmıştır. Anılan konuya ilişkin su tüketimi birinci yıl 999 mm, ikinci yıl ise 1052 mm olarak belirlenmiştir. Sözkonusu sulama konusunda dekara verim 1993 yılında 1001.5 kg; 1994 yılında ise 1003.5 kg olmuştur. Çalışmanın ilk ve ikinci yılında, CWSI hesaplamasında gerekli olan su stresinin olmadığı alt sınır (LL) eşitlikleri sırasıyla Tc-Ta=2.9- 2.66 VPD ve Tc-Ta=2.41-2.045 VPD; bitkinin tamamen su stresinde olduğu üst sınır (UL) değerleri ise sırasıyla 4.25o C ve 3.50o C olarak bulunluştur. Sulama zamanındaki infrared termometre ölçümlerinden, mısır dane veriminin düşmeye başladığı eşik CWSI değeri 0.21 olarak saptanmıştır. Ayrıca, mısır dane verimi ile CWSI arasında doğrusal bir ilişki olduğu belirlenmiştir.This study was carried out to determine crop water stress index (CWSI) using the infrared thermometer data; to estimate irrigation time from this index and to obtain yield-CWSI relationships for maize under Çukurova Region conditions. In this research, irrigation water levels were 100% (I100), 80% (I80), 60% (I60), 40% (I40), 20% (I20) and 0% (I0 ) of water depleted in the 120 cm soil profile in every ten days, so different level of water stress treatments were created. A total of 752 mm and 823 mm of irrigation water were applied to I100 irrigation treatment, in which water depletion was determined as 999 mm and 1052 mm in 1993 and 1994, respectively. Grain yield obtained from the above mentioned irrigation treatment was 1001.5 kg/da in the first year and 1003.5 kg/da in the second year of the experiment. In the first and second experimental year, non-water-stressed (LL) and water-stressed (UL) baselines were developed as Tc-Ta=2.9- 2.66 VPD and Tc-Ta=2.41-2.045 VPD; 4.25o C and 3.50o C, respectively. The yield reudction threshold CWSI values were determined as 0.21 using the infrared thermometer (IRT) readings. Linear relationship was also found between grain yield and CWSI

Determination of emitter spacing based on the amount of water applied and trickle discharge rates

Farklı damlatıcı debilerinin ve uygulanan sulama suyu miktarlarının toprak profilinde nem dagılımına etkileri ile ıslatılan toprak hacminde ıslanma cephesinden ve Wooding (1968) yönteminden yararlanarak damlatıcı aralıgı belirlenmesinin amaçlandığı bu çalışma killi toprakta yürütülmüştür. Arastırmada 16, 32 ve 64 L toplam sulama suyu 2, 4, 6 ve 8 L/h damlatıcı debileriyle ayrı ayrı uygulanmıs ve sulamadan 48 saat sonra suyun damlatıcıdan itibaren yanal olarak 45-60 cm’ye dek ilerledigi saptanmıştır. Damlatıcı debisi ve uygulanan toplam sulama suyu miktarı arttıkça suyun yanal hareketi de artmıştır. Killi toprak için damlatıcı aralığı, debiye ve uygulanan sulama suyuna baglı olarak 90-130 cm arasında değişmiştir. Topragın bazı fiziksel özelliklerinden yararlanarak, Wooding (1968) yöntemiyle belirlenen damlatıcı aralığının ise 44-93 cm arasında degistigi belirlenmiştir. Sulama suyunun 16 L uygulandığı koşullarda damlatıcı debileriyle damlatıcı aralıkları arasında ikinci dereceden, 32 L uygulanması durumunda ise dogrusal bir iliski bulunmuştur.This study was conducted with the objectives of determining effect of trickle discharge rates and amount of irrigation water applied on water distribution in the soil profile and to estimate the emitter spacing by the Wooding method and wetting front in the wetted soil volume in a clay soil. Total volume irrigation water of 16, 32 and 64 L were applied with discharge rates of 2, 4, 6 and 8 L/h and water has moved laterally to a distance of 45-60 cm from the trickle source 48 hrs after water application. Result of this study indicated that as the flow rates and amount of water applied increased, rate of moisture movement in the horizontal direction also increased. Experimental emitter spacing changed from 90 to 130 cm in the clay soil depending on the emitter discharge rates and volume of water applied. Using the same physical properties of soil, emitter spacing estimated by Wooding's equation varied from 44 to 93 cm. A second order relation was obtained between the emitter flow rates and emitter spacings when a total of 16 L water was applied.. When the amount of water applied was increased to 32 L, the relationship was linear

Verification and validation of ceres-wheat model under Çukurova conditions

Plant Growth models have been presently used extensively by engineers and planners in order to evaluate various management alternatives. Plant growth models are tools for predicting crop growth parameters by using mathematical equation of complex environmental dynamics. In this study, CERES-Whea V2. 1 plant growth simulation model was verified and validated on PANDA wheat variety under Çukurova Conditions. Different amounts of irrigation water were applied to wheat. For this purpose a line-soruce sprinkler irrigation system was utilized in the experiment. Wheat rows adjacent to the lateral were denoted as non water stress treatmen (I1), rows outside the weted area were denoted as non-irrigated treatment (I5); the plant rows in between the I1 and I5 treatments were taken as the deficit irrigation treatments with linearly decreasing amount. Meteorological data required by the model were obtained from the automatic recording type weather station in the experimental area of the Deparment of Agricultural Structures and Irrigation of the Çukurova University and from the Meteorological station of Adana province. Throughout the experiment, soil water, phenological growth stages, biomass samples, and leaf area index (LAI), kernel weight, etc. were determined

Some performance parameters of individual sprinkler irrigation systems efficiency used in Konya-Ilgın Plain

Bu çalışma, Konya Ilgın Ovası’nda kullanılan yağmurlama sulama sistemlerinin performanslarını değerlendirmek, bu sistemlerin ne denli etkin çalıştıklarını ortaya koymak ve sistem performanslarını iyileştirmek için ne gibi önlemlerin alınması gerektiğini belirlemek amacıyla yürütülmüştür. Bu amaçla ovayı temsil edecek şekilde dokuz yağmurlama sulama sistemi seçilmiştir. Çalışmada, Christiansen türdeşlik katsayısı (CU), dağılım türdeşliği (DU), su uygulama randımanı, yağmurlama başlık basıncı ve değişimi, yağmurlama başlık debisi ve değişimi, sulama öncesi toprak nem açığı, sulama suyu miktarı, sulama aralığı ve sulama sayıları her bir sistem için değerlendirilmiştir. Her bir sulamanın su dağılım türdeşliği tekil lateral su dağılım testleri yapılarak belirlenmiştir. Sulama sırasında doğrudan buharlaşma ve rüzgarla sürüklenme miktarları ampirik eşitliklerle saptanmıştır. Sonuçta DU değerlerinin %36,8 ile %81,5 arasında; CU değerlerinin de %58,0 ile %82,0 arasında değiştiği belirlenmiştir. Ayrıca, değerlendirme çalışması yapılan sistemler üzerinde basınç ve debi değişimlerinin izin verilen sınırların üzerinde olduğu belirlenmiştir.The on-farm sprinkler irrigation systems used in the Ilgın Plain in Konya Province in Central Anatolia (Turkey) were evaluated in order to determine the efficiency of the systems as they are being used, and to determine how effectively the systems can be operated and whether they can be improved, and to obtain information that will assist engineers in designing other systems. A total of nine sprinkler systems were evaluated in the field by determining the uniformity coefficient (UC), distribution uniformity (DU), and application efficiency (AELQ), sprinkler flow rates, pressures at each sprinkler on the lateral, soil moisture deficit prior to and irrigation, duration of irrigation, irrigation interval, yield of sugarbeets and potatoes were determined for each system studied. The distribution uniformity (DU) of irrigation for studied each system was evaluated by means of the catch-can tests. Evaporation from the catch cans during the tests was also estimated. Wind drift losses were estimated using empirically determined equations. DU values ranged from 36.8 to 81.5% for the systems evaluated. UC values varied from 58.0 to 82.0%. Both the DU and UC values obtained were lower than the recommended values. Pressure variation and flow variation along the lateral were estimated to be much higher than the recommended values. In general, systems were operated at a lower pressure than required

A new method for automatic water supply to furrows: (cablegation)

''Cablegation'' karık sulamada su iletimi ve dağıtımı için kullanılan delikli boru sisteminin otomasyonudur. Bu sistemde karık yöntemi ile sulanan arazide tarla başına yerleştirilen bir boru hattı hem suyun taşınmasına hemde dağıtılmasına hizmet eder. Boru çapı mevcut eğimde uygun akış miktarını boruu tam doldurmadan taşıyacak büyüklükte seçilir. Boru hattı üzerindeki orifisler karık tarafına doğru düşeyle 30o'lık açı yapacak şekilde konumlandırılır. Su, boru içinde bulunan bir tıkaç yardımı ile orifisden akmaktadır. Tıkaç'ın konumu ve hareketi ana boru içinde tıkaca bağlı olan bir kablo ile kontrol edilmektedir. Bir bilgisayar modeli ve arazi testleri sonuçlarından, tıkaç orifis yakınında iken akış en yüksek; tıkaç menbadan uzaklaştıkça akış giderek azalmakta ve toplam debi, orifis büyüklüğü, orifis aralığı ve boru hattının eğimine bağlı olarak menbadan belirli uzaklıkta akış sıfır olmaktadır. Bu makalede cablegation sisteminin genel özellikleri ve işletim esasları anlatılmaktadır