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Öğe Does Application of Water Retention Barrier to Soil Increase Salt Content Within Soil Profile?(Univ Namik Kemal, 2012) Demirel, K.; Kavdir, Y.In thi s research, effects of water retention barrier (WRB) that was placed under effective rooting depth of turfgrass, on change of electrical conductivity and soil pH were investigated in Canakkale-Ezine in 2010 and 2011. Treatments were WRB application depths (30 cm and 40 cm) and three different i rrigation levels were applied for each depth. In this study, EC and pH were analyzed by taking soil samples at twice a year. According to the results, application of WRB on sandy soil does not significantly changed soil EC and pH values for two years.Öğe Grain size-induced changes in carbon and nitrogen concentrations and characteristics of tomato harvest residue biochar(Springer, 2020) Ilay, R.; Kavdir, Y.; Memici, M.; Ekinci, K.The production of biochar is one of the new methods used in the recycling of organic wastes. The use of biochar may increase carbon storage in the soil for longer periods of time. In this study, carbon and nitrogen contents of different sizes of tomato harvest residue biochar (TB) produced at different temperatures and holding times were determined. TB produced at five different temperatures (300, 400, 500, 600, 700 degrees C) and three different durations (20, 40, and 80 min) was divided into three different grain size classes (< 0.5, 0.5-2, and 2-4 mm). Total carbon (C) and nitrogen (N) contents of each size class were examined. Production temperature significantly affected N contents of TB (p < 0.05) while changes in the C contents due to temperature were not statistically significant (p > 0.05). On the other hand, effect of TB size on C and N contents was statistically significant (p < 0.05). As TB grain size increases, BET surface area and total pore volume increased, while average pore radius decreased. The larger size of biochar (2-4 mm) demonstrated highly porous and honey-combed structures and contained both micro- and mesopores, which create a high specific surface area. It was suggested that the properties of biochar produced under the same conditions may vary according to their size and different sizes of biochar may be preferred according to the intended use.Öğe Monitoring composting process of olive oil solid waste using FT-NIR spectroscopy(Taylor & Francis Inc, 2020) Kavdir, Y.; Ilay, R.; Camci Cetin, S.; Buyukcan, M. B.; Kavdir, I.FT-NIR (Fourier Transform-Near Infrared) spectroscopy has been used for the prediction of properties of various materials. Olive oil solid waste compost (OSWC) can be a good and available source for soil organic matter in Mediterranean countries. This study was aimed at developing a fast and nondestructive method for determining compost carbon to nitrogen (C/N) ratio, total nitrogen (TN), inorganic nitrogen, total carbon (C), pH and electrical conductivity (EC) using FT-NIR spectroscopy. Composts were sampled weekly and some chemical analyses were performed on the samples using standard methods. Also, reflectance spectra of the same compost were acquired using FT-NIR spectroscopy right after the standard measurements. Organic matter functional groups of OSW and OSWC were compared using C-13-NMR spectroscopy. Calibration models between the standard measurements and the spectral measurements performed on samples were established applying Partial Least Squares (PLS) method. According to prediction models following determination coefficients (R-2) of 0.86, 0.82, 0.81, 0.77, 0.75, 0.65 and 0.51 were obtained respectively for nitrate (NO3-), pH, ammonium (NH4+), total N, C/N ratio, total C and EC. With this study, it was shown that FT-NIR spectroscopy has the potential of sensing OSWC parameters nondestructively.Öğe Plant carbon and nitrogen contributions to the formation and function of soil aggregation processes in sustainable agroecosystems(Organisation for Economic Cooperation and Development (OECD), 2003) Smucker, A.J.M.; Kavdir, Y.; Dell, C.J.; Rasse, D.P.Soil aggregate formation is controlled by crop and soil management, mineral, carbon and ion contents, internal drainage and associated weathering processes. Plant carbon (C) and nitrogen (N) components of soil organic matter (SOM) are key ingredients controlling the formation, function, and stability of soil aggregates. Although SOM content has been reported to be associated with aggregates of different size fractions, little is known of the soil C and N dynamics occurring within aggregates of different size fractions. Using stainless steel soil aggregate erosion (SAE) chambers, we have been able to identify multiple gradients within concentric layers from large numbers of individual soil aggregates ranging in size from 1-15 mm across. Soil tillage, cultivation, cover crops and rotations greatly modify the locations and concentrations of C, N, P and microbial communities within soil aggregates. Soil C recently deposited on aggregate surfaces is highly labile while most older and more recalcitrant C is sequestered in the central regions of aggregates. Soil aggregates associated with living roots of cover crops sequester much more N than shoot N or when plants are absent. A greater understanding of the dynamics within and at surfaces of soil aggregates will solve many mysteries of the magnificent root soil interface. © OECD 2003.Öğe Removal of metals and metalloids from acidic mining lake (AML) using olive oil solid waste (OSW)(Springer, 2019) Ilay, R.; Baba, A.; Kavdir, Y.The acidic mining lakes have low pH values and high metal and metalloid concentrations. In this study, the ability of low-cost olive oil solid waste (OSW) to remove Al, As, Cd, Fe, B and Ti ions from aqueous solutions in short term has been evaluated. Adsorption capacities (mgg(-1)) of OSW (1:5-1:10w/v) were 764.06-411.75 for Al, 0.26 for As, 0.07-0.14 for Cd, 2181.5-2406.5 for Fe, 23.70-82.50 for B and 0.12-0.0.34 for Ti. OSW addition increased acidic mine water (AMW) pH from 2.41 to 3.2 with 1:5 and from 2.41 to 2.7 to 1:10 mixing ratio, respectively, after 10min. The best gradual decrease has been observed with different ratio of OSW applications on B and Ti concentrations. OSW adsorbs 32.41% and 62.68% of B at the ratio of 1:5 and 1:10 and 55.29% and 83.04% of Ti at the ratio of 1:5 and 1:10 (OSW:AMW) mixtures, respectively. The results show that OSW has great potential for metal removal from acidic mine water.Öğe Seasonal variations of nitrous oxide emission in relation to nitrogen fertilization and energy crop types in sandy soil(Elsevier Science Bv, 2008) Kavdir, Y.; Hellebrand, H. J.; Kern, J.Nitrous oxide (N(2)O) is a greenhouse gas and agricultural soils are major sources of atmospheric N(2)O. Its emissions from soils make up the largest part in the global N(2)O budget. Research was carried out at the experimental fields of the Leibniz-Institute of Agricultural Engineering Potsdam-Bornim (ATB). Different types (mineral and wood ash) and levels (0, 75 and 150 kg N ha(-1)) of fertilization were applied to annual (rape, rye, triticale and hemp) and perennial (poplar and willow) plants every year. N(2)O flux measurements were performed 4 times a week by means of gas flux chambers and an automated gas chromatograph between 2003 and 2005. Soil samples were also taken close to the corresponding measuring rings. Soil nitrate and ammonium were measured in soil extracts. N(2)O emissions had a peak after N fertilization in spring, after plant harvest in summer and during the freezing-thawing periods in winter. Both fertilization and plant types significantly altered N(2)O emission. The maximum N(2)O emission rate detected was 1081 mu g N(2)O m(-2) h(-1) in 2004. The mean annual N(2)O emissions from the annual plants were more than twofold greater than those of perennial plants (4.3 kg hat vs. 1.9 kg ha(-1)). During January, N(2)O fluxes considerably increased in all treatments due to freezing-thawing cycles. Fertilization together with annual cropping doubled the N(2)O emissions compared to perennial crops indicating that N use efficiency was greater for perennial plants. Fertilizer-derived N20 fluxes constituted about 32% (willow) to 67% (rape/rye) of total soil N20 flux. Concurrent measurements of soil water content, NO(3) and NH(4) support the conclusion that nitrification is main source of N20 loss from the study soils. The mean soil NO(3)-N values of soils during the study for fertilized soils were 1.6 and 0.9 mg NO(3)-N kg(-1) for 150 and 75 kg N ha-1 fertilization, respectively. This value reduced to 0.5 mg NO(3)-N kg(-1) for non-fertilized soils. (c) 2007 Elsevier B.V. All rights reserved.Öğe Using Chlorophyll Meter to Predict Sunflower Nitrogen Content after Olive Solid Waste Applications(Int Soc Horticultural Science, 2009) Kavdir, Y.; Ilay, R.; Turhan, H.; Genc, L.; Kavdir, I.; Sumer, A.Chlorophyll index is an instantaneous measurement of leaf greenness without the destruction of the plant and a new tool to determine plant nitrogen content and associated yield. A pot experiment was conducted under controlled conditions. Olive solid wastes were mixed with soil at the rates of 0, 3, 5 and 7% with and without additional nitrogen and phosphorous sources. Sunflower was grown in pots for two months. Plant length, leaf number, stem thickness, and chlorophyll meter readings were performed weekly. Plant nitrogen contents and plant weights were determined at harvest. Chlorophyll index and plant nitrogen contents were significantly related (r(2) = 0.86) at the V12 stage. The correlations between chlorophyll meter reading and plant biomass was 0.87 while plant N and plant biomass was 0.96. On the other hand, chlorophyll meter estimation of plant N contents in early stages (V2 and V4) of sunflower growth was not statistically significant. Additions of olive solid waste in the soil reduced chlorophyll meter readings and sunflower biomass.
