Moisture Retention Caracteristics in the Soil Formed upon Limestones and Dolomites in the Republic of Macedonia

The paper presents results from the research of the influence of soil texture on the water retention curves of calcomelanosols, calcocambisols and terra rossa in Republic of Macedonia. The content of the fi ne soil separates in the calcomelanosols varies depending on the subtype. The physical sand fraction (coarse sand + fi ne sand) in the Amo horizon amounts to: 44.81% in the organomineral calcomelanosols, 40.13% in the organogenic and 36.52% in brownised calcomelanosols. In the (B)rz horizon in the brownised calcomelanosols it amounts to 32.64%. The contents (clay + silt) or physical clay in the Amo horizon amounts to: 55.19% in the organomineral calcomelanosols, 59.87% in the organogenic, and the highest content was in the brownised calcomelanosols, 63.48%. The average value of this fraction in the horizon (B) rz in the brownised calcomelanosols amounts to 67.36%. In the calcocambisols the average content of the physical sand fraction in the Amo horizon amounts to 33.43%, and in the cambic horizon (B)rz 22.50%. In the terra rossa the fraction physical clay is represented with a greater percentage related to the physical sand fraction. In the Amo horizon in the physical clay fraction the clay fraction is predominant, average 43.08% and 52.13% in the cambic horizon, 24.90% in Amo and 19.37% in the silt fraction. There is the highest retention capacity, average 41.48% in the humus-accumulative horizon Amo in the calcomelanosols, subtype organogenic. The remaining subtypes of calcomelanosols have lower retention capacity in this horizon. As with retention capacity of 0.33 required in other points of tension (6.25 and 15 bar) it shows the same condition; mean value of organogenic was 29.39 and 17.22%, respectively, then organomineral 23.98 and 18.34%, respectively, and brownised calcomelanosols 21.70% and 16.60%, respectively. The average retention values in the Amo horizon and the cambic horizon (B)rz regarding calcocambisols amounts to 33.49% and 33.24%. The average retention values (pressure of 6.25 = 625 kPa and 15 bar = 1500 kPa) in the Amo horizon and the cambic horizon (B)rz regarding calcocambisols amounts to 25.27% and 17.06% respectively, and 27.89% and 16.68%, respectively. The average retention capacity in terra rossa, amounts to 39.05% in the Amo horizon, and 40.25% in (B)rz. The average retention values (pressure of 6.25 and 15 bar) in the Amo horizon and the cambic horizon (B)rz regarding terra rossa amounts to 29.92% and 20.93%, respectively, and 33.23% and 23.38%, respectively. The results from our research show that in Amo and (B)rz horizons there is a positive correlation between the water retention curves at 0.33; 6.25 and 15 bars and contents of physical clay (clay and silt) and clay. Also there is high negative correlation between the retention curves at 0.33 bars contents of physical sand fractions (coarse sand+fi ne sand; r = -0.47)

ОПРЕДЕЛУВАЊЕ НА БИОКЛИМАТСКИ КОЕФИЦИЕНТ КАЈ ДОМАТ ПРИ ПРИМЕНА НА РАЗЛИЧНИ ТЕХНИКИ НА НАВОДНУВАЊЕ И ЃУБРЕЊЕ

The experimental trial was conducted with tomato hybrid Optima at open field near by the Faculty of Agricultural Sciences and Food in Skopje, during the period of May to September in 2003 and 2004. The main aim of this investigation was to determinate bioclimatic coefficient of tomato crop in Skopje region under different irrigation and fertilization techniques. Five different treatments of irrigation and fertilization regime of tomato crop were aim of our investigation. The first three treatments were irrigated by drip irrigation and drip fertigation, the treatment four was irrigated with drip irrigation and conventional application of fertilizers and the last one the treatment five was under furrow irrigation and conventional application of fertilizers. From the average results in two years of investigation, it can be concluded that the lowest average bioclimatic coefficient shows treatments В1 and В2 (drip fertigation every 2 and 4 days) or 1,66 and 1,67. As a result of longer irrigation frequencies (drip fertigation every 6 days), bioclimatic coefficient in treatment В3 was 1,71 or 2,4 to 3% higher in comparison with В2 and В1. Тhe control treatment with drip irrigation and conventional application of fertilizers (Ø1) showed same results as treatment В2, which is result of irrigation regime. The effect of irrigation techniques on bioclimatic coefficient is presented by the comparison of the results from the control treatments Ø1 and Ø2 (furrow irrigation and conventional application of fertilizers). Namely, control treatment Ø2 show the highest hydrophytotermical coefficient or 2,15, which is almost 29% higher value in comparison with Ø1

Effect of Regime of Irrigation and Fertilization of Sugar Beet (Beta vulgaris L.) on Yield of Sugar

The aim of this research was to analyze the effects of different variants of irrigations and fertilization of sugar beet (Beta vulgaris L.) on the yield of total sugar. The study was performed in agro-ecological conditions in valley Pelagonija in R. of Macedonia in period from 2012 to 2014. The following different regimes of irrigation were applied: irrigation at 75% utilized available water (uAW); 50% uAW; 25% uAW; and irrigation on the basis of bioclimatic coefficient (BC). Control was a variant without irrigation. The fertilization was applied at three different levels: low, medium and high. Control was a non-fertilized variant.This study is very important because simultaneously supplying of sugar beet with water and mineral matters is required for achievement of high and quality yields. The highest yield of total sugar was obtained in a irrigation treatment with 50% uAW and medium dose of fertilization. Keywords: sugar beet (Beta vulgaris L.); irrigation, fertilization; total sugar yield

PHYSICAL-CHEMICAL PROPERTIES OF WATER IN CRNA RIVER IN THE PELAGONIA REGION

The main purpose of this paper is to examine the physical-chemical properties of water in Crna River in the Pelagonia Region. Therefore, four locations along the Crna River in the Pelagonia Region were taken as target measuring points of the physical-chemical properties of water: measuring point 1 (near village Novaci), measuring point 2 (before the inflow of water to the fifth channel), measuring point 3 (Crna River after the inflow of water from the fifth channel) measuring point 4 (Skochivir). The water samples for analysis were taken in January and July in 2012, 2013 and 2014 and the following physico-chemical parameters were analyzed during our investigation: the water temperature (determined with a digital thermometer), turbidity (by turbidimeter), suspended solids, total organic carbon (TOC), biological oxygen demand (BOD), chemical oxygen demand (COD) and dissolved oxygen (determined with UV PASTEL-instrument). From the obtained results in our investigation it can be concluded that the highest average turbidity is noted in measuring point 1 (24,4 mg/L) in July. The highest average BOD is measured in point 3 (14,1 mg/L) in July, as a result of the water inflow from the fifth channel. The lowest average amount of TOC was noted in January in measuring point 1 (2,0 mg/L), while the content of dissolved oxygen in same measuring point show the highest value (11,53 mg/L)

The Influence of Drip Fertigation on Water Use Efficiency in Tomato Crop Production

The primary objective of this study was to determine the best irrigation and fertigation practice for tomato crop (Lycopersicon esculentum Mill.) in order to achieve highest yield with maximum water use efficiency (WUE). The field experiments were conducted during the period of May to September in 2002, 2003 and 2004. Five experimental treatments tested in this study included the following: the first three treatments (T1, T2, and T3) included a combination of drip irrigation and fertigation, treatment four (T4) included drip irrigation, but with conventional application of fertilizer, and the fifth treatment, (T5), included furrow irrigation practice with conventional application of fertilizer. The results of this study show that the drip fertigation treatments (T1, T2, and T3) gave significantly higher tomato yields in comparison with treatments T4 and T5, almost 24% and 39%. During three years of research treatments under drip fertigation showed almost 28% more water use efficiency in comparison with the treatment with conventional application of fertilizer and drip irrigation and 87% more than the treatment with furrow irrigation and conventional application of fertilizer. So, it is clear that the drip fertigation led to an increased yield, indicating enhanced water use efficiency

Nitrogen Fertilizer Use Efficiency of Pepper as Affected by Irrigation and Fertilization Regime

The pepper producers in the Republic of Macedonia have used drip irrigation systems to increase yield in recent years, but more research is still needed, related to irrigation scheduling and precise requirement of nitrogen fertilizer to maximise pepper yield. Therefore, a two year experiment was conducted in a plastic house to determine the nitrogen fertilizer use efficiency (NFUE) and yield potential of pruned pepper as affected by irrigation and fertilization regime. Four experimental treatments were applied in this study. Three of the treatments were drip fertigated (DF1, DF2, DF3), while the fourth treatment was furrow irrigated with conventional fertilization (ØB). The labelled urea with 1% concentration of a stable isotope of nitrogen (15N) was applied for determination of NFUE. The results of this study clearly showed that increased NFUE and pepper yield depend on irrigation and fertilization regime. Namely, NFUE was significantly increased with the application of nitrogen fertilizer through drip irrigation system as compared to conventional fertilization with furrow irrigation. Also, drip fertigation frequency positively affects percentage increase of NFUE. Furthermore, our results showed that drip fertigation treatments resulted in significantly higher pepper yields in comparison to conventional fertilization. Also, drip fertigation frequency at four and two days (DF2 and DF1) resulted in higher yields when compared with drip fertigation scheduled by using tensiometers (DF3). Generally, to reach acceptable pepper yield with high NFUE, we recommend drip fertigation with a frequency of two to four days combined with two main shoots of pruned pepper in order to increase farmer’s income and to minimize the environmental impact

RAPESEED (BRASSICA NAPUS, L.) – BIOLOGICAL REQUIREMENTS, GROWING CONDITIONS AND NEED FOR IRRIGATION

Rapeseed is one of the most important energy and food crops. The European agricultural producers are highly interested in it due to the obligations under the EU Directive for replacing the fossil fuels with biofuels as much as 20% by 2020, which has drawn the purchase prices considerably up. Rapeseed is widely used for production of cooking oil and rich in protein feed too. As regards to the environment, it contributes for restoration of degraded and contaminated lands owing to its capability for improving soil structure and leaving the area free of weeds. Rapeseed is one of the best pre-crops of winter wheat and contributes for some 20-30% increase of its yield. The paper contains an overview of different aspects of rapeseed growing: its biological requirements and the abiotic stressing factors in the Balkan geographic region; its sensibility to water and the impact of the water deficit on the yield and yield structural components; its yearly and monthly evapotranspiration and crop coefficients at different empirical evapotranspiration calculation methods; world data on its yields and the agricultural practices such as proper irrigation scheduling for its yield increase. The conclusions show that the soil and the climatic conditions on the Balkans are suitable for rapeseed growing and irrigation can contribute for obtaining sustainable yields from this crop

Procjena specijacije kadmija u saliniziranim okolišnim uvjetima

Povećanje saliniteta i sadržaja elemenata u tragovima u površini tla putem neodgovarajućih praksi gospodarenja zemljištem (fertirigacija, aplikacija kondicionera tla) predstavlja jednu od najraširenijih prijetnji sigurnosti i zaštiti hrane u suvremenoj poljoprivredi. Fitodepozicija, kao najznačajniji način unosa biotoksičnog i neesencijalnog kadmija (Cd) u ljudske namirnice, korespondira pozitivno sa salinitetom rizosfere. Pomoću kemijsko specijacijskog računalnog pristupa (Visual MINTEQ) procijenjen je biogeokemizam Cd-kontaminirane (1µM) otopine s različitim razinama (nizak-visok) jednih od najzastupljenijih prirodnih minerala (Na+15-150, Cl- 12-90 i SO42- 1.5-30 mM) u širokom pH (3.5-9.5) rasponu i niskom prisustvu otopljenog organskog ugljika (1 mg DOC/L). Na temelju modeliranih rezultata, koncentracija slobodnog Cd2+ je dominirala u većini testiranog pH raspona kod niskog saliniteta, dok su u okruženju srednjeg do visokog saliniteta prevladavale koncentracije Cd-Cl- i Cd-SO4-kompleksiranog sadržaja Cd. NICA-Donnan modeliranjem je potvrđena važnost Cd-organo-kompleksiranog sadržaja jedino pri višim pH vrijednostima (>8.0) i nižem salinitetu. Rezultati potvrđuju da kao posljedica smanjenog otopljenog organskog sadržaja uslijed povećanog saliniteta (npr. prirodno salinizirana tla, vode korištene za navodnjavanje u poljoprivredi) biogeokemizam Cd u rizosferi može pospješiti mobilnost Cd, a time i njegovu fitoekstrakciju od strane navodnjavanih kultura

ВЛИЈАНИЕ НА КАПКОВОТО НАВОДНУВАЊЕ И ФЕРТИРИГАЦИЈА ВРЗ МЕСЕЧНИОТ И ВЕГЕТАЦИСКИОТ ХИДРОФИТОТЕРМИЧКИ КОЕФИЦИЕНТ КАЈ ПИПЕРКАТА

The main aim of this investigation was to determinate the effect of drip fertigation on hydofphytotermical coefficient of two stem pruned pepper crop (“V”system). The field experiments were conducted with green pepper crop ‘Bela dolga’ grown in experimental plastic house near by the Faculty of Agricultural Sciences and Food in Skopje, during the period of May to October in 2005, 2006 and 2007. Therefore, four experimental treatments were applied in this study. Three treatments were irrigated with drip irrigation and drip fertigation (KK1, KK2, KK3), while the last one was irrigated with furrow irrigation and conventional application of fertilizer (control treatment ØB). From the results obtained during the three years of investigation, it can be concluded that the average hydrophytotermical coefficient in 2005 is 1.52 in 2006 the coefficient is decreasing (1.46), while in 2007 hydrophytotermical coefficient again is increasing (1.48). According to year of investigation, the treatments with drip fertigation (KK1, KK2, KK3) shows from 14.6 to 23.6% lower average hydrophytotermical coefficient in comparison with treatment with furrow irrigation and traditional application of fertilisers ØB