Browsing by Author "Sahin, Ustun"

Now showing 1 - 19 of 19

Biochar and Mycorrhiza Enhance Soil Carbon Storage and Reduce Co2 Emissions in Wastewater-Irrigated Turf
(Iwa Publishing, 2023) Sahin, Ustun; Cakmakci, Talip; Yerli, Caner
Irrigation with recycled wastewater can reduce freshwater demand and improve soil fertility, but it can also increase CO2 emissions from soil and contribute to global warming. This study investigated whether biochar and mycorrhiza can reduce CO2 emissions and enhance soil quality in wastewater-irrigated turf. A factorial experiment was conducted with four levels of biochar (0, 0.5, 1, and 1.5%), two mycorrhiza (with and without), and two types of irrigation water (freshwater and recycled wastewater). Soil CO2 and H2O emissions, moisture and temperature, and chemical and physical properties were measured for 3 months. Biochar and mycorrhiza treatments significantly reduced CO2 emissions by 19.4-45.0% compared to the control treatment. The combination of biochar at a 1.5% level with mycorrhiza had the highest emission-reducing effect. Biochar and mycorrhiza treatments also reduced H2O emissions by 8.1-14.6%, increased soil organic matter, carbon, and total nitrogen, regulated soil EC and pH, and improved soil porosity and aggregate stability. The results suggest that biochar and mycorrhiza can be effective strategies to mitigate CO2 emissions and improve soil quality in wastewater irrigation. The combination of biochar with mycorrhiza can have synergistic benefits for soil carbon storage and conservation.
Co2 Emission From Soil in Silage Maize Irrigated With Wastewater Under Deficit Irrigation in Direct Sowing Practice
(Elsevier, 2022) Yerli, Caner; Sahin, Ustun; Oztas, Taskin
It is necessary to understand and measure the impact of tillage and irrigation practices on CO2 emissions from the soil with an environmental sensitivity, while wastewater irrigation increases crop biomass yield. The main objective of the present study was to investigate the changes and reasons in CO2 emissions from soil conventional and conservative tillage under different levels of wastewater irrigation. The CO2 emission from tillage-sowing to harvest over the regular measurements with a EGM-5 infrared gas analyzer device was investigated with three replicates in three deficit irrigation levels (0%, 33%, and 67%) of domestic recycled wastewater in conventional tillage and direct sowing practices. Binary relationships of CO2 emissions with H2O emission, air temperature, and the soil temperature and moisture measured at three different depths (5 cm, 10 cm, 20 cm) were also investigated and strong (p < 0.01) positive linear correlations were determined. Wastewater irrigation and conventional tillage significantly increased CO2 emissions compared to freshwater irrigation and direct sowing practice, while deficit irrigation practice decreased it. The direct sowing reduced seasonal CO2 emissions 25.1% and 26.1% for per unit area (1 ha) of silage maize and per unit of fresh silage yield (1 kg), respectively, compared to conventional tillage. The lowest CO2 emission per unit area and yield was determined in full irrigation treatment with freshwater in direct-sowing, while, in wastewater applications, it was determined in irrigation levels 33% per unit area and 67% per unit yield, under direct sowing. Thirty-three percent and 67% treatments in direct sowing resulted in less seasonal CO2 emissions as 38.7% per unit area and 13.8% per unit fresh silage yield, respectively compared to full irrigation treatment with freshwater in conventional tillage. Mean CO2 emissions in these treatments were found lower 17.9% per unit area and higher 17.8% per unit fresh silage yield compared to the full irrigation treatment with freshwater in direct-sowing. It was concluded that CO2 emissions per unit yield could be decreased with 33% water saving under wastewater irrigation conditions, and could be achieved environmental additional benefits from more decreasing CO2 emission by direct sowing also.
Co2 Emissions and Their Changes With H2o Emissions, Soil Moisture, and Temperature During the Wetting-Drying Process of the Soil Mixed With Different Biochar Materials
(Iwa Publishing, 2022) Yerli, Caner; Cakmakci, Talip; Sahin, Ustun
Biochar is an organic regulator that improves crop yield by regulating soil properties. In addition, this organic regulator is also effective in reducing CO2 emissions from soil. However, considering the management of CO2 emissions together with many factors and the different properties of soil depending on the biochar content, CO2 emissions can vary. Thus, the study investigated the soil moisture and temperature and H2O emission, which affect the emission, and CO2 emission of biochars with different raw materials applied to the soil in the wetting-drying cycle of the soil. It was determined that biochar applications decreased CO2 emissions, but the share of each biochar material in reduction differed, and CO2 emissions were 82, 51, 20, and 13% lower in straw, hazelnut, apple, and sawdust biochar applications than in soil without biochar, respectively, and significant positive linear relationships of CO2 emissions with soil moisture-temperature and H2O emissions were determined. In addition, in biochar applications, H2O and soil temperature decreased depending on the moisture retention in the soil increased. In the findings, it can be suggested that straw biochar application to soil is more effective in reducing the severity of increasing global warming, and that soil moisture and temperature should be managed to reduce CO2 emissions.
Deficit Irrigation With Wastewater in Direct Sowed Silage Maize Reduces Co2 Emissions From Soil by Providing Carbon Savings
(Iwa Publishing, 2022) Yerli, Caner; Sahin, Ustun; Kiziloglu, Fatih Mehmet; Oztas, Taskin; Ors, Selda
Direct sowing and deficit irrigation practices can reduce the effect of wastewater on CO2 emissions from soil by providing carbon savings. Therefore, the effect of domestic recycled wastewater uses at different levels in irrigation under conventional tillage and direct sowing practices on the CO2 emission from soil at the end of the vegetation period of silage maize was investigated by comparing it with full irrigation of fresh water. Both organic carbon and CO2 emissions in the second year in fully irrigated treatments were higher than those in the first year. The CO2 emission in the full irrigation with wastewater (0.263 g m(-2) h(-1)), compared to full irrigation with fresh water and 33 and 67% deficit irrigations with wastewater, was higher at 23.4, 25.0, and 59.3%, respectively. Direct sowing practice also (0.193 g m(-2) h(-1)) resulted in 17.0% less CO2 emission as compared to conventional tillage. The positive linear relationships of H2O emission and the soil moisture content at different depths (5, 10, and 20 cm) with CO2 emission were significant, and the negative relationships with the soil temperatures were also found. It has been concluded that deficit irrigation and direct sowing applications can be practical for reducing CO2 emissions from soil in wastewater irrigation conditions.
The Effect of Arbuscular Mycorrhizal Fungi on Carbon Dioxide (Co2) Emission From Turfgrass Soil Under Different Irrigation Intervals
(Iwa Publishing, 2024) Boyno, Gokhan; Yerli, Caner; Cakmakci, Talip; Sahin, Ustun; Demir, Semra
Increased nutrient and/or water uptake by arbuscular mycorrhizal (AM) symbiosis can affect soil biochemical properties and emission of the greenhouse gas carbon dioxide (CO2). Therefore, an experiment was designed to investigate the effect of AM fungi (AMF) on CO(2 )emissions from turfgrass. Three different AMF species (Funneliformis mosseae, Claroideoglomus etunicatum, and Rhizophagus irregularis) were used in this experiment. Turfgrass plants were cultivated in pots containing both mycorrhizal and non-mycorrhizal soils over a 10-week period. To mimic real-world conditions, the plants underwent irrigation cycles at intervals of 1, 2, and 3 days, replicating common irrigation practices in turfgrass fields. The research aimed to comprehensively understand the effects of AMF and varying irrigation intervals on CO2 emissions, soil characteristics, plant growth, and AMF parameters. It was observed that the changing irrigation intervals affected the AM symbiosis and this effect increased as the irrigation interval increased. It was determined that this AM symbiosis created with the plant significantly reduced CO2 emissions. In addition, it was determined that it regulates the soil structure and increases plant growth. In conclusion, it can be said that AMF species reduce CO2 emissions by reducing the need for water in the turfgrass.
The Effect of Cucumber (Cucumis Sativus) Cultivation in Aquaponic and Hydroponic Systems on Plant Nutrient Elements and Antioxidant Enzyme Activity
(Parlar Scientific Publications (p S P), 2018) Guzel, Senol; Odun, Ugur Cansin; Cakmakci, Talip; Cakmakci, Ozlem; Sahin, Ustun
Search for raw materials, especially for those used in food production, gained further importance with the increasing world population. In recent years, aquaponic systems which integrated form of fish and plant cultivation were increasingly preferred in the search for new food sources. In this study, culture mediums in aquaponic and hydroponic systems were investigated for koi carps (Cyprinus carpio) and cucumber plants (Cucumis sativus). At the end of the study, nutrient element and chlorophyll contents with antioxidant enzyme activities of the plants grown in aquaponic and hydroponic systems were compared. The comparison between aquaponic and hydroponic systems showed that the differences between the systems in terms of Ca, Na and P were not statistically significant, while there was a statistically significant difference in K and Mg levels among the macro elements between the systems. Differences in microelements (B, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were significant among systems. In the aquaponic system, Cd, Cr, Fe, Ni, Pb, and Zn levels were higher compared to those in the hydroponic system, while B, Cu and Mn levels were higher in the hydroponic system. There was no difference in antioxidant system activities (CAT, APX, MDA, SOD) in both systems. The difference between the systems in terms of chlorophyll content was significant, and chlorophyll content in the hydroponic system was higher than that in the aquaponic system.
Effect of Different Manure Applications and Wetting-Drying Cycles on Co2 Emissions From Soil
(Gh Asachi Technical Univ Iasi, 2021) Yerli, Caner; Sahin, Ustun
Organic carbon is transformed into CO2 by various interventions applied to the soil and diffuse to the atmosphere. The manures which used unconscious under available soil moisture and temperature condition makes the soil microorganism activity increased. This causes CO2 emission increase as well by oxidation of organic matter. In this study, it was aimed to evaluate different amounts of sheep (20, 40 and 60 t ha(-1)) and poultry (15, 30 and 45 t ha(-1)) manure under different wetting-drying cycles (irrigation intervals of 3, 6 and 9-days) in terms of CO2 emission and to understand the relationship of soil temperature and soil moisture with CO2 emission. The study was conducted according to arranged in a complete randomized block design with three replications as a pot study in greenhouse conditions. The frequent irrigation and using high amount of manure increased CO2 emissions. Although the same amount of organic matter was provided to the soil in different amounts of sheep and poultry manures, CO2 emission was higher in sheep manure. Soil temperature increased by irrigation at infrequent intervals and high amount of manure. Moisture retention in the soil increased by using high amount of manure. The linear relationship of soil temperature (R-2=0.922) and soil moisture (R-2=0.895) with CO2 emission was found to be quite significant (P<0.01). As a result of the study, using low amount of poultry manure (15 or 30 t ha(-1)) instead of sheep manure and irrigation at infrequent intervals (9-days) can be suggested as precautions to decrease CO2 emissions.
The Effect of Using Treated Wastewater With Different Irrigation Methods on Silage Maize Macro-Micro Element and Heavy Metal Accumulation
(Univ Namik Kemal, 2020) Cakmakci, Talip; Sahin, Ustun
This study was carried out in Van (Turkey) province, has semi-arid climate in 2015 and 2016. In the study, it was aimed to determine the macro micro nutrient element and heavy metal content changes in silage maize by comparing the wastewater (AS) applications with different irrigation methods [Subsurface drip (SSDI), surface drip (SDI), traditional furrow (FI)] and irrigation levels [full irrigation (% 100; K0), % 33 deficit (K1) and % 67 (K2) deficit] with clean water (TS). In treated wastewater applications, increases in the N, P, K, Ca, Mg, B, and Fe contents of the plant were increased by about 28%, 28%, 26%, 12%, 47%, 23% and 24% respectively. In heavy metal contents (Cu, Mn, Zn, Pb, Cd, Cr and Ni), changes between 75% and 770% were observed. Moreover, in all three irrigation methods, the micro-trace element accumulation order in the plant was realized as Fe> Mn> Zn> B> Cu> Cr> Pb> Ni> Cd. Along with the irrigation water limited, macro and micro element contents in plants have decreased. At the end of the study, it was concluded that nutrient supplements can be added to silage maize with treated wastewater, and can be safely used as an alternative source of irrigation water in regions where irrigation water is insufficient.
Effects of Arbuscular Mycorrhizal Fungi on Carbon Dioxide (Co2) and Water (H2o) Emissions in Turfgrass Soil Under Different Salinity Irrigation Levels
(Gh Asachi Technical Univ Iasi, 2023) Boyno, Gokhan; Yerli, Caner; Cakmakci, Talip; Sahin, Ustun; Demir, Semra
Host plants inoculated with arbuscular mycorrhizal (AM) fungi are widely believed to tolerate stressful situations such as heat, salinity, drought, metals, and extreme temperatures. However, increased nutrient and/or water uptake by AM symbiosis may affect soil biochemical properties and emissions of the greenhouse gas carbon dioxide (CO2). Therefore, an experiment was designed to investigate the effect of AM fungi on CO2 and water (H2O) emissions in lawns. Three different AM fungi species were used in this experiment (Funneliformis mosseae, Claroideoglomus etunicatum and Rhizophagus irregularis). Turfgrass plants were grown in pots in mycorrhizal and non-mycorrhizal soils for ten weeks, and the plants were subjected to irrigation cycles with salted water at 0.6, 4.5, 6.0, and 7.5 dS m(-1) ratios. The effects of AM fungi and saline irrigation at different rates on CO2 and H2O emissions and their effects on plant morphological growth and AM fungi parameters were also evaluated. At the end of the experiment, it was seen that irrigations with different salt ratios affected AM fungi, which was negative as the salt ratio increased. Nevertheless, a symbiosis was established between the plant and the AM fungi. CO2 and H2O emissions and soil temperature decreased with mycorrhiza treatments and increased irrigation water salinity. In addition, it was determined that AM fungi increased plant growth under salt stress. Among the AM fungi species, especially C. Etunicatum was more successful.
Effects of Deficit Irrigation on Essential Oil Composition and Yield of Fennel (Foeniculum Vulgare Mill) in a High-Altitude Environment
(Taylor & Francis inc, 2018) Coban, Furkan; Ozer, Hakan; Ors, Selda; Sahin, Ustun; Yildiz, Gul; Cakmakci, Talip
Successful fennel (Foeniculum vulgare Mill) production in semi-arid environments depends largely on irrigation applications. Deficit irrigation studies on fennel are lacking or very limited, particularly in high-altitude environments. This study was conducted to determine the effects of deficit irrigation levels on the essential oil content, essential oil yield, and chemical composition of fennel. The experiment was carried out in 2014 and included four deficit irrigation levels: 100% (I-1), 80% (I-2), 60% (I-3), and 40% (I-4) of Class A pan evaporation. All parameters were significantly affected by deficit irrigation applications. Essential oil content tended to increase under increased water deficit conditions with the range of 2.21% to 2.42%. Anethole (90.71-91.62%) was the major compound in the fennel fruit oil, followed by estragole (3.60-4.02%), limonene (2.19-3.24%), and fenchone (0.96-1.55%), respectively. Essential oil yield showed an increase with increased irrigation amounts.
Fertility and Heavy Metal Pollution in Silage Maize Soil Irrigated With Different Levels of Recycled Wastewater Under Conventional and No-Tillage Practices
(Springer, 2025) Yerli, Caner; Sahin, Ustun; Oztas, Taskin; Ors, Selda
Irrigation with recycled domestic wastewater has been known to obtain positive effects on improving soil fertility, but it may also become a risk factor in case of causing an increase in soil salinity and/or heavy metal concentration of soil. No-tillage can retain soil moisture, helping to reduce irrigation water necessity, and thus lower amounts of heavy metals and salts are added to soil under wastewater irrigation conditions. The objective of this study was to analyze the effects of wastewater irrigation at different levels of on silage maize cultivation under conventional tillage and no-tillage conditions by comparing to full irrigation with fresh water. The two-year experiment was planned according to the split-plots design in the random blocks with three replications. The results indicated that full irrigation with wastewater increased soil salinity, organic matter content, total nitrogen, plant available phosphous, exchangeable cations, exchangeable sodium percentage and soil essential and non-essential heavy metal contents, but decreased soil pH and lime content. Increasing rates in organic matter content, total nitrogen, plant available phosphorus and exchangeable potassium were higher, but in electrical conductivity, and heavy metal accumulation were lower in soil under no-tillage as compared to conventional tillage. Contamination and enrichment factors and geographic accumulation index showed that non-essential heavy metal contamination due to cadmium and nickel, increased in full irrigation with wastewater. Irrigation with wastewater also increased heavy metal accumulation in silage maize. No-tillage can be a recommendable water management practice considering that the risks of soil salinity and heavy metal accumulation can be reduced and that soil fertility can be increased. Also, in reducing the risk of accumulation of cadmium and nickel in soil, 33% deficit irrigation with wastewater can make no-tillage more available.
Improvement of Water and Crop Productivity of Silage Maize by Irrigation With Different Levels of Recycled Wastewater Under Conventional and Zero Tillage Conditions
(Elsevier, 2023) Yerli, Caner; Sahin, Ustun; Ors, Selda; Kiziloglu, Fatih Mehmet
Although wastewater irrigation has a long history involving different stages of development, the future expec-tation to improve crop yield and water productivity in wastewater irrigation practices is still relevant. Therefore, the aim of this study is to evaluate water productivity, yield and crop quality of silage maize irrigated with different application levels (100%, 67%, and 33% of irrigation need) of recycled wastewater with three replicates in conventional tillage and zero tillage practices and comparing them with full fresh water irrigation. The results of two-year field studies showed that zero tillage resulted in saving 10.1% of irrigation water on average compared to conventional tillage and actual evapotranspiration in silage maize with zero tillage was 7.4% less. Biomass yield was the highest in full irrigation with wastewater under zero tillage. Zero tillage practice provided 12.0% and 13.2% higher water productivity(WP) and irrigation water productivity(WPirrig), respectively compared to conventional tillage. The WP was higher in treatments with wastewater with 100% and 67% irri-gation levels, while the WPirrig was higher in treatment with wastewater with 67% irrigation level. While the crop total soluble solids, nutrients, crude protein, chlorophyll(SPAD), leaf area index and leaf relative water content (LRWC) values were higher in full irrigation with wastewater, acid and neutral detergent fibers and membrane damage was lower. Crude protein in zero tillage was lower than in conventional tillage, while SPAD and LRWC were higher. It could be concluded that wastewater can increase silage maize biomass yield and crop quality. This result may be more valuable in terms of both protecting scarce fresh water resources and contributing to the environment with waste disposal. Moreover, 67% irrigation treatment with wastewater can be preferred for the higher WP and WPirrig values, and zero tillage can be used as a practical treatment that contributes to the yield and water saving.
Improving Silage Maize Productivity Using Recycled Wastewater Under Different Irrigation Methods
(Elsevier, 2021) Cakmakci, Talip; Sahin, Ustun
The contribution of wastewater irrigation with the improvement of irrigation practices to the productivity of silage maize is a priority issue to investigate considering the saving of scarce freshwater resources and the necessity to dispose wastewater. The aim of this study was to evaluate the effect of different irrigation levels (L100, L67 and L33) of recycled municipal wastewater (RW) compared to freshwater (FW) using subsurface drip (SSDI), surface drip (SDI) and furrow irrigation (FI) methods on yield and some physiological traits of silage maize in semi-arid conditions at a high altitude. When the total daily reference evapotranspiration value reached 50 +/- 5 mm, irrigation quantities corresponding to 100%, 67% and 33% of soil moisture deficit based on field capacity in fully irrigated plots with freshwater were applied in different irrigation levels. Crop actual evapotranspiration (ETa) values were found close in both water types. SSDI reduced ETa by 18.5% and 45.6% in L100 level, 15.2% and 38.9% in L67, and 11.6% and 32.6% in L33, respectively compared to SDI and FI. The highest fresh biomass yield was determined in the SSDI-RW-L100 combination as 77.55 t ha-1, and resulted in 5% and 12.9% higher values than in SDI and FI. Leaf relative chlorophyll and water contents, leaf area index and electrolyte leakage showed strong linear correlations with yield and evapotranspiration values. The highest water productivity was determined in the SSDI-RW-L100 combination as 21.48 kg m-3 and it was higher by 28.2% and 99.4% than those in SDI and FI, respectively. Improvement of productivity with increased irrigation quantities in SSDI delivered the high yield response factor of 1.70-1.77. Therefore, it is concluded that the SSDI method can be a successful practice to improve productivity by alleviating the need for water for silage maize especially under full irrigation with RW.
Pre-Sowing Soil Carbon Dioxide Emissions of the Following Year From the Silage Maize Field Irrigated With Different Levels of Wastewater in Conventional and Direct Sowing Practices
(Iwa Publishing, 2023) Yerli, Caner; Sahin, Ustun
While knowing CO2 emissions during the seasonal period are important, determining residual effect before sowing in the following year can be an available practice in improving wastewater irrigation strategies. Therefore, this study investigated CO2 emission from the silage maize field plots irrigated with wastewater at different levels under conventional and direct sowing in the pre-sowing period after two experimental years by comparing freshwater with full irrigation, and correlated with H2O emission and, soil moisture and temperatures. The results showed that irrigation with wastewater and conventional tillage in the previous two years resulted in higher CO2 emissions in the following period also, and 27 and 11% higher emissions were determined in irrigation with wastewater at 100 and 67% levels than full freshwater irrigation. In irrigation with wastewater at 100% level and direct sowing, soil moisture was found higher, while reduced H2O emission and the soil temperatures at 5 and 10 cm depths. Considering moisture conservation effect of direct sowing, it could be concluded that to reduce on the residual CO2 emission effect of irrigation with wastewater from previous years, deficit irrigation in direct sowing can be recommended practice.
Productivity and Heavy Metal Pollution Management in a Silage Maize Field With Reduced Recycled Wastewater Applications With Different Irrigation Methods
(Academic Press Ltd- Elsevier Science Ltd, 2021) Cakmakci, Talip; Sahin, Ustun
Using wastewaters in irrigated agriculture can cause heavy metal accumulation as well as salinity in soil. A practical way of minimizing accumulation in soil is to use irrigation techniques that require less water and consequently introduce less heavy metals into the feeding chain in silage maize cultivation with wastewater irrigation. The objective of this study is to address this issue. A factorial field experiment was carried out for two years in a completely randomized design with three replicates. Experimental plots were irrigated with three different irrigation methods (subsurface and surface drip, and furrow) applying three different levels (full irrigation and 33 and 67% deficit irrigations) of recycled wastewater and freshwater. The results showed that soil heavy metal contents, salinity, macro nutrients, organic matter, cation exchange capacity, porosity and wet aggregate stability were significantly higher in full irrigation with wastewater, while pH, carbonates, bulk and particle densities were significantly lower. Drip methods reduced salinity and heavy metal contents significantly. Heavy metal pollution indexes also indicated that drip methods are more effective in reducing metal pollution in soil. However, considerable accumulations of Cd and Ni were found with all methods while deficit irrigation decreased accumulations. The highest cation exchange capacity and K2O contents and the lowest exchangeable sodium percentage were determined with the subsurface drip method. The subsurface drip method saved 20.7 and 49% more irrigation water than the surface drip and furrow methods under fully irrigated conditions. Therefore, it can be concluded that using the subsurface drip method with recycled wastewater can be used in silage maize cultivation because soil productivity and water savings increased while metal pollution and salinity in soil decreased. Moreover, using 33% less wastewater can be a useful practice to decrease Cd and Ni accumulation.
Reducing Gray, Blue, Green, and Total Water Footprint in Wastewater Irrigated Silage Maize in Zero Tillage
(Iwa Publishing, 2024) Yerli, Caner; Sahin, Ustun
No study has been found examining the contribution of gray water footprint input per unit yield to reducing blue and green water footprint output in silage maize irrigated with different levels of wastewater under different tillage practices. Therefore, this 2-year silage maize field study examined the effect of three different levels of recycled wastewater (100, 67, and 33% of irrigation need in W100, W67, and W33) and 100% irrigation with freshwater on water footprint under conventional and zero tillage. Under zero tillage, W100 had the lowest blue, green, and total water footprint per unit yield of 2.8, 6.1, and 47 m(3) ton(-1) for fresh biomass, respectively, and 9.2, 20.1, and 155.3 m(3) ton(-1) for dry biomass. Among the wastewater treatments, the W33 resulted in the highest water footprints per unit yield under conventional tillage. Blue, green, gray, and total water footprints per unit fresh yield under zero tillage were 9.8, 5.9, 13.1, and 10.3% lower than conventional tillage, while the values for dry biomass were 15, 14.3, 18.6, and 16.6% lower. In conclusion, W100 under zero tillage can be an effective way to protect freshwater resources by reducing blue, green, and total water footprint outputs with less gray water footprint input per unit yield.
Reduction of Blue and Total Water Footprints Per Unit Biomass Yield of Silage Maize With Grey Water Footprint Input in Subsurface Drip Irrigation
(Iwa Publishing, 2024) Cakmakci, Talip; Sahin, Ustun
Reducing blue and total water footprint outputs in irrigated agriculture with greywater footprint input from irrigation with recycled wastewater is an issue that needs to be investigated in protecting freshwater resources by increasing water availability. Therefore, the effect of three different irrigation levels of recycled wastewater and freshwater in the subsurface irrigation (SSDI), surface drip irrigation (SDI), and furrow irrigation (FI) methods on the blue, green, grey, and total water footprints per unit yield of silage maize, which is widely produced worldwide and has high water consumption, was investigated with a 2-year field study. The blue and total water footprints per unit fresh and dry biomass yields in the SSDI were 1.20-1.23-fold lower than that in the SDI and 1.69-1.76-fold lower than that in the FI. Full wastewater irrigation provided the lowest blue, green, and total water footprints per unit yield across all methods. Full wastewater irrigation under SSDI provided the lowest total water footprint per unit fresh biomass yield, similar to the 33% deficit irrigation practice with wastewater. It was concluded that full irrigation with recycled wastewater as a greywater resource under SSDI may be the most suitable application for the sustainable management of scarce blue water resources.
Soil Co2 Emission Linearly Increases With Organic Matter Added Using Stabilized Sewage Sludge Under Recycled Wastewater Irrigation Conditions
(Springer int Publ Ag, 2023) Yerli, Caner; Cakmakci, Talip; Sahin, Ustun
Although adding organic matter by applying sewage sludge and recycled wastewater in agricultural lands is beneficial for most functions expected of soils, mainly by improving soil structure and fertility, it is a potential source of carbon dioxide (CO2) emissions. This study aimed to analyze the changes in CO2 emissions by season and per unit of organic matter from bare soil with the organic matter added under recycled wastewater irrigation conditions. Therefore, an experiment in containers was conducted in a greenhouse with two water types (freshwater and recycled wastewater) at five different organic matter levels (control: 1.91%, and then 2.45%, 2.99%, 3.53%, and 4.07%) by mixing in stabilized sewage sludge. The experiment was repeated three times in total. Containers were irrigated a total of ten times at 6-day intervals. CO2 emissions were directly measured at the beginning and end, and at 3 days after each irrigation cycle, with an EGM-5 infrared gas analyzer device. Water (H2O) emissions from the soil, the soil moisture, and temperatures were also recorded during the CO2 emission measurements. The results showed that higher rates of organic matter in soil resulted in higher CO2 emissions from the soil that linearly increased with organic matter content for both water types, while there were lower CO2 emissions per unit of organic matter. The mean CO2 emissions with increasing doses were found to be higher by 17.9%, 30.6%, 43.0%, and 56.4%, respectively, compared to the control. Recycled wastewater resulted in 9.5% higher emissions compared to freshwater. The decreasing amounts of CO2 emissions per unit of organic matter with increasing doses were determined to be 8.1%, 17.1%, 24.6%, and 27.2%, respectively, compared to the control. Increasing organic matter and irrigation with recycled wastewater increased soil moisture and temperature values while decreasing H2O emissions from the soil. Strong linear correlations of CO2 emissions with H2O emissions, soil moisture, and temperatures were determined. Therefore, soil carbon sequestration in irrigated conditions can be improved by managing soil moisture; thus, the contribution of the increased organic matter in the soil to improve soil properties and productivity can be increased.
Yield, Physiological Responses and Irrigation Water Productivity of Capia Pepper (Capsicum Annuum L.) at Deficit Irrigation and Different Biochar Levels
(Springer, 2023) Cakmakci, Talip; Sahin, Ustun
This study aimed to determine the effects of three irrigation water levels on the yield, soluble solid content and some physiological traits of pepper plants in soils mixed with biochar at four different doses. The study was conducted as a pot experiment in three replications for each treatment setup in a completely randomized design under greenhouse conditions. The experiment comprised controlled/full irrigation (I0), 25% deficit irrigation (I1), 50% deficit irrigation (I2), and four biochar treatments: non-biochar at 0% (B0), biochar at 0.75% (B1), biochar at 1.5% (B2), and biochar at 3% (B3). Biochar application significantly increased pepper growth and yield. Significant improvements in the physiological properties of the plant with the increase in biochar dose (B1, B2, and B3) in deficit irrigation applications were determined. Under the 50% water deficit conditions (I2), the biochar amendments (B3I2, B2I2, and B1I2) increased the irrigation water productivity compared to the control (non-biochar, B0I2), as well as water savings of 18.4, 12.8 and 8.3%, respectively. Biochar amendments increased the moisture retention in the soil and saved irrigation water. In this study, the highest efficiency was obtained from the B3 (3% w:w) treatment. In addition, biochar increased irrigation water productivity by improving soil properties under water deficit conditions.