Narrow Row Corn Production with Subsurface Drip Irrigation

시설오이 지중관비에서 지중 점적호스를 30 cm에 매설 시에 텐시오미터를 이용한 자동관수센서의 적정 깊이를 제시하고자 2010-2011년까지 2년간에 걸쳐서 조사하였다. 오이의 생육은 텐시오미터 30 cm 깊이에서 낮았으나 텐시오미터 10 및 20 cm에서는 유의성 있는 차이는 없었다. 1년 및 2년차 수량에서도 텐시오미터 30 cm에서 각각 40.9 및 41.2 <TEX>$Mg\;ha^{-1}$</TEX>로 가장 적은 생산량을 나타내었나, 텐시오미터 10 cm에서는 57.0 및 56.9 <TEX>$Mg\;ha^{-1}$</TEX>, 텐시오미터 20 cm에서는 56.0 및 60.5 <TEX>$Mg\;ha^{-1}$</TEX>로 처리간의 차이가 없이 동일한 수량을 나타내었다. 오이재배에서 한 작기 당 질소 및 일일 물 공급량은 63 <TEX>$kg\;N\;ha^{-1}$</TEX>의 질소와 1.3 <TEX>$mm\;day^{-1}$</TEX>로 물이 공급된 텐시오미터 20 cm 처리에서 질소 및 수분 이용효율이 높았다. 또한 토양깊이 0-30 cm에 대한 뿌리길이에서도 텐시오미터 20 cm에서 0.87 <TEX>$cm\;cm^{-3}$</TEX>으로 유의성은 없었지만 가장 높은 값을 나타내었다. 이러한 결과로부터 시설오이에서 지중 점적호스를 30 cm 깊이에 매설 시에 텐시오미터를 활용한 자동관수센서의 적정 깊이는 20 cm인 것으로 판단되었다. Vegetables production in greenhouse are typically intensely managed with high inputs of fertilizers and irrigation water, which increases the risk of ground-water nitrate contamination. In 2010 and 2011, a study was conducted to determine the appropriate depth of soil moisture sensor for automatic irrigation control to use water and nitrogen efficiently under subsurface drip irrigation (SDI) systems. The irrigation line for SDI placed 30 cm below soil surface and tensiometer was used as soil moisture sensor. Three tensiometer treatments placed at 10 (SDI-T10), 20 (SDI-T20) and 30 cm (SDI-T30) depths below soil surface under SDI. These are also compared to SUR-T20 treatment where tensiometer placed at 20 cm below soil surface under surface drip irrigation (SUR) systems. The growth of cucumber was not statistically different between SUR and SDI without SDI-T30 treatment. Fruit yields (Mg/ha) were 57.0 and 56.9 (SDI-T10), 56.0 and 60.5 (SDI-T20), 40.9 and 41.2 (SDI-T30) and 56.6 and 54.3 (SUR-T20) for 2010 and 2011, respectively. Slightly higher total yield was observed in tensiometer placed 20 cm below the soil surface, although no significant differences were found between SDI-T10 and SDI-T20 under SDI treatments. In addition, nitrogen application rates and daily irrigation rates were lowest in SDI-T20 compared with other SDIs and SUR treatments. Nitrogen and daily irrigation application under SDI-T20 was lower than that under SUR-T20 by 6.0%. These findings suggested tensiometer 20 cm depth under SDI systems was best for cucumber production in greenhouse.

Water is an essential component of life in the world. In addition to being crucial to keeping plants alive, water is also used in various areas, such as landscape irrigation, decorative pools, and ponds. The use of water more efficiently is getting more and more important day by day because of the increasing demands of different sectors. In cities with limited water resources, such as Konya, water should be used even more efficiently to reduce irrigation water quantities and prevent water losses. The potential use of the sub-surface drip irrigation method in the irrigation of green areas in Selçuklu district of Konya province was investigated, and the sub-surface drip irrigation method was compared with the fixed sprinkler irrigation method (pop-up) in terms of irrigation parameters (amount of irrigation water applied, plant water consumption) and plant characteristics (germination, plant height, number of mows, mowing weight, root depth). In the present experiments, 18 different sub-surface drip irrigation treatments (100, 80, and 60% irrigations + 40, 60, and 80 cm lateral spacings + 10 and 15 cm lateral depths) and three different sprinkler irrigation treatments (100, 80, and 60% irrigations) were used. Present findings revealed that sub-surface drip irrigation systems were suitable for irrigation of green areas, and this system was more advantageous for municipalities in terms of water savings, irrigation labor, and maintenance. For sub-surface drip irrigation systems, S1 (supply 100% of evaporation from Class-A pan + 40 cm lateral spacing + 10 cm lateral depth) treatments were found to be the best system arrangement for landscape irrigations in Selçuklu district in Konya province.

Over two growing seasons, we evaluated how irrigation strategies and lateral spacings under drip irrigation methods shape safflower physiology. A split-split plot design tested full irrigation (FI), partial root-zone drying (PRD), and deficit irrigation (DI) across three lateral spacings (L1 = 20, L2 = 40, and L3 = 60 cm) with surface (SD) and subsurface (SSD) drip irrigation systems. We monitored leaf area index (LAI), photosynthesis rate (An), stomatal conductance (gs), leaf transpiration rate (Tr), leaf water potential (LWP), and leaf to air vapor pressure deficit (VPD) and related these to seed yield. Relative to FI, water-saving irrigation strategies reduced seasonal irrigation by ~ 25–26%, and SSD applied ~ 7% less water than SD. Peak LAI was 3.95 (2018) and 4.88 (2019), and it significantly reduced by an average of 14% and 18% with water-saving irrigation and wider later spacing, respectively, in comparison to FI and 20 cm lateral spacing. Gas exchange parameters (An, gs, and Tr) decreased with wider lateral spacing and peaked under FI and 20 cm lateral spacing, though PRD and 40 cm spacing resulted in an acceptable physiological performance under water scarcity. The LWP was less negative under FI by roughly 18% compared to water-saving irrigation and by 24% under L1 compared to L3. The extinction coefficient (k) of spring safflower for SD and SSD was 0.62 and 0.70 on average during the two growing seasons. Subsurface drip irrigation showed slightly higher light extinction coefficient, suggesting altered canopy light absorption. Collectively, treatments optimized for gas exchange properties and seed yield were FI-L1-SSD. When water is scarce, the most effective saving strategy was PRD-L2-SSD, which maintained An, gs, LWP, and An/Tr better than DI while saving ~ 25% seasonal water compared to FI.

Tomato yield, biomass accumulation, root distribution and irrigation water use efficiency on a sandy soil, as affected by nitrogen rate and irrigation scheduling

A field experiment was conducted at the Arkansas Valley Research Center in 2005 through 2007 to study the effects of manure and nitrogen fertilizer on corn yield, nutrient uptake, N and P soil tests, and soil salinity under furrow and drip irrigation. Manure or inorganic N was applied in 2005 and 2006 only. There were no significant differences in corn yield between drip and furrow irrigation even though, on average, 42% less water was applied with drip irrigation. Inorganic N or manure application generally increased grain yield, kernel weight, grain and stover N uptake, and grain P uptake. Nitrogen rates above 67 kg ha−1 did not increase grain yield significantly in 2005 or 2006, nor did manure rates in excess of 22 Mg ha−1. High manure rates increased soil salinity early in the season, depressing corn yields in 2005 and 2006, particularly with drip irrigation. Salts tended to accumulate in the lower half of the root zone under drip irrigation. Residual nitrate nitrogen from manure and inorganic N application sustained corn yields above 12.0 Mg ha−1 in 2007. More research is needed to develop best manure and drip irrigation management for corn production in the Arkansas Valley.

Proximity to subsurface drip irrigation emitters altered soil microbial communities in two commercial processing tomato fields

Tomato nitrogen accumulation and fertilizer use efficiency on a sandy soil, as affected by nitrogen rate and irrigation scheduling

Growing concerns about climate change and water scarcity have intensified the need for sustainable turfgrass management, particularly by optimizing water‐use efficiency. This 2‐year field study evaluated the effects of rootzone construction methods and irrigation delivery systems on water retention characteristics and perennial ryegrass performance under 60% reference evapotranspiration (ETO) deficit irrigation. Three rootzone constructions (two two‐layered and one three‐layered) were investigated using sprinkler and subsurface drip irrigation (SDI) systems. Key parameters assessed included soil water tension, rootzone water storage (RWS), turfgrass quality (TQ), turfgrass coverage, and normalized difference vegetation index. Significant interactions between rootzone construction and irrigation systems were observed. The three‐layered SDI system demonstrated significantly higher RWS and TQ than the two‐layered SDI systems, which showed rapid RWS and TQ decline. While two‐layered sprinkler systems maintained acceptable TQ longer than their SDI counterparts, they proved to be less efficient than the three‐layered SDI system. These findings highlight the critical role of aligning rootzone design with irrigation methods in enhancing water‐use efficiency and turfgrass performance in water‐scarce environments. This study provides valuable insights for sustainable turfgrass management strategies in response to increasing water constraints.

The rapid expansion of animal production in the eastern U.S. in the 1990s resulted in large quantities of concentrated animal waste that must be utilized or disposed of in an efficient and environmentally friendly manner. To address these environmental concerns for wastewater utilization, we installed a subsurface drip irrigation system to apply treated swine wastewater effluent for bermudagrass hay production. The overall study objective was to determine the feasibility of using subsurface drip irrigation (SDI) for treated wastewater effluent applications. The specific objectives for the SDI system were to compare bermudagrass hay production using (1) commercial and wastewater effluent for nutrients, (2) two SDI lateral spacings (0.6 and 1.2 m) installed at 0.3 m below the surface, and (3) two irrigation application rates based on calculated evapotranspiration (ETc) requirements (75% or 100%). The two-year study measured hay yields, hay biomass, soil nutrients, and soil water nutrients. The SDI system was successfully operated for two years applying effluent and commercial fertilizer to supply the nutrient requirements of the bermudagrass hay. Bermudagrass hay production for 2004 and 2005 ranged from 5.65 to 14 Mg ha-1. Results from the SDI system indicated no significant differences between the SDI lateral spacings or irrigation application rates. Treatments using wastewater effluent had significantly higher hay yields and significantly higher nutrient biomass removal rates than the commercial fertilizer treatments. Nitrate-N observed in soil water lysimeters increased with depth, indicating the potential for leaching without proper management. Soil nitrogen and carbon were not significantly different for any of the treatments but did vary slightly over the life of the project.

The main objective of this study was to compare different irrigation systems based on a parametric evaluation system in an area of 3070 ha on the Dasht Bozorg Plain, Khuzestan Province, southwestern Iran. Soil properties in the study area such as texture, depth, electrical conductivity, drainage, calcium carbonate content and slope were derived from a semi-detailed soil study carried out on the Dasht Bozorg Plain on a scale of 1:20 000. Once the soil properties were analysed and evaluated, suitability maps were generated for surface, sprinkle and drip irrigation systems using remote sensing (RS) techniques and GIS (Geographic Information System). The results showed that for 1567.6 ha (51.1%) in the study area sprinkle irrigation was highly recommended, whereas for 1876.6 ha (61.3%) in the study area drip irrigation would be extremely efficient and suitable. However, there were no highly suitable lands for surface irrigation, but for all irrigation systems no unsuitable land exists in the study area. The results showed that by applying sprinkle irrigation instead of drip and surface irrigation, the arability of 1611.6 ha (52.5%) on the Dasht Bozorg Plain will improve. In addition, by applying drip irrigation instead of sprinkle or surface irrigation, the land suitability of 802.4 ha (26.2%) on this plain will improve. A comparison of the different types of irrigation systems revealed that sprinkle and drip irrigation were more effective and efficient than surface irrigation for improving land productivity. It is noteworthy, however, that the main limiting factor in using sprinkle and/or drip irrigation in this area is the soil calcium carbonate content and the main limiting factors in using surface irrigation are soil calcium carbonate content together with drainage.

Water being scarce resources, irrigation water is the most limiting factor for vegetable production in the central rift valley of Ethiopia. Drip irrigation technique together with deficit irrigation application improves crop yield and water use efficiency. Hence, the objective of this study was to enhance onion production and WUE through the application of drip irrigation technology and deficit irrigation application. Field experiment was conducted at Melkassa agricultural research center during the cool cropping season of 2019/2020 to investigate the effects of drip lateral spacing and irrigation levels on onion yield, water use efficiency and net return. Two levels of drip lateral spacing viz., lateral placed in every row and between two rows, and three levels of deficit irrigation viz., 80% ETc, 70% ETc and 55% ETc, and one-full irrigation (100% ETc). The treatments were arranged in split plot with three replications. Data were analyzed using statistical package appropriate to split plot with the help of SAS software. The result showed that onion yield, yield parameters and water use efficiency was affected by the effects of drip lateral spacing and irrigation water levels but not affected by their interaction effect. Onion bulb yield decreased with increased levels of water deficit. In contrast, both water use efficiency and irrigation water use efficiency increased with increase in water deficit level. Maximum onion bulb yield of 41.43 t ha-1 were obtained from lateral spacing in every row and full irrigation application level of 100% ETc and has no a significant difference with every row lateral spacing, and 85% and 70% ETc irrigation application levels. The highest water use efficiency of 13.33 Kgm-3 was recorded from every row drip lateral spacing and irrigation application of 70% ETc. Therefore, onion could be irrigated every row drip lateral spacing with 70% ETc application to increase water use efficiency without a significant total bulb yield reduction.

Increasing water demand and climate change reduced agricultural water resources in arid and semi-arid regions. Field experiments were conducted at Demo Farm, Faculty of Agriculture, Fayoum University. Potato tubers were planted during two seasons (2021 and 2022). Three deficit irrigations (DI): I1 (100% of ETc), I2 (80% of ETc) and I3 (60% of ETc). Two partial root zone drying (PRD) irrigations: (double laterals and single laterals). Three lateral depths: zero cm (surface drip irrigation) and 15 and 30 cm (subsurface drip irrigation, SDI). Some growth parameters and yield of the potato crop were determined. Results indicated that the highest mean values of plant growth and yield of potato plants were recorded with irrigation treatment I1 under PRD and SDI with buried lateral depth of 15 cm. Also, the highest values of physiological parameters were recorded with irrigation treatment I1 under PRD and SDI with buried lateral depth 15 cm. When DI treatments increased from I1 to I2 and I3, the mean values of potato yield decreased. Using PRD treatment led to increasing the values of potato yield at irrigation treatments I1, I2 and I3. It could be recommended when irrigation water is abundant, using the irrigation treatment I1, PRD irrigation under SDI with buried lateral depth at 15 cm to reach the maximum yield of the potato crop. Meanwhile, under water scarcity, using DI treatment I2, PRD irrigation under SDI with buried lateral depth at 15 cm, will save 20% of the IWA with a low decrease in potato yield.

The influence of several regulated deficit irrigation (RDI) strategies, applied under subsurface drip irrigation (SDI), on vegetative development and yield parameters in mature almond (Prunus dulcis (Mill.) D.A. Webb, cv. Cartagenera) trees was analysed during a 4-year field experiment. Five treatments were applied: T1 (100% crop evapotranspiration (ETc), full season); T2 (irrigated at 100% ETc except in the kernel-filling stage (20% ETc)); T3 (equal to T2 but in SDI); T4 (SDI, 100% ETc, except in the kernel-filling stage (20% ETc) and post-harvest (75% ETc)); T5 (SDI, 100% ETc except in the kernel-filling stage (20% ETc) and post-harvest (50% ETc). A close correlation between applied water, plant water status (Ψpd) and tree growth parameters was observed. After four years, the vegetative development in T5 was reduced significantly due to a larger annual cumulative effect of water stress on growth processes, resulting in a smaller tree size (trunk and branch growth, canopy volume and pruning weight) compared to other treatments. Moreover, water stress during kernel-filling produced a significant reduction in the leaf expansion rate and a stimulation of premature leaf abscission, resulting in a smaller tree leaf area in this treatment. SDI produced a greater horizontal distribution of fine roots in the soil profile than surface drip system. The RDI practices applied under subsurface drip irrigation stimulated a deeper root development (40–80 cm) than surface treatments (0–40 cm), producing also a higher root density in the subsurface treatments watered the least (T4 and T5). Water stress during the pre- and post-harvest periods had no important effect on bud development, bloom, fruit growth or fruit abscission. Moreover, there were no significant reductions in kernel dry weight or kernel percentage. Reductions in kernel yield were significant compared to T1, being of 11% in T2, 15% in T3, 20% in T4 and 22% in T5. Water use efficiency (kg m−3) was increased significantly in the SDI treatments T4 and T5. A significant correlation between kernel yield and tree growth parameters was observed. We conclude that the application of overall reductions of water use of up to 50% during high water stress sensitivity periods (such as post-harvest) under SDI system, is a promising alternative for water management in semiarid regions in order to improve water use efficiency. Nevertheless prolonged water stress during kernel-filling and post-harvest can reduce excessively the vegetative development of almond, negatively affecting the long-term yield response.

The influence of undercanopy sprinkler and drip irrigation systems on growth and yield of bananas (cultivar ‘Williams’) in the subtropics

Drip irrigation and biochar amendment could affect the nitrogen form and transformation. Creating a deep understanding of the interacting effects of drip irrigation patterns and biochar on soil mineral nitrogen, as well as the key functional genes and microbial community involved in nitrogen transformation is helpful for improving facility agricultural management, increasing water and nitrogen use efficiency, and reducing the nitrate accumulation and groundwater pollution caused by nitrogen leaching. Four treatments [surface drip irrigation (D), insert drip irrigation (ID, insert depth 15 cm), surface drip irrigation +10 t·hm-2 of biochar (DB), and insert drip irrigation +10 t·hm-2 of biochar (IDB)] were conducted in a solar greenhouse, and non-rhizospheric and rhizospheric soils of pepper plants were studied. There was no effect of drip irrigation patterns and biochar on ammonium-nitrogen in the non-rhizospheric and rhizospheric soils. Compared with surface drip irrigation, insert drip irrigation decreased the nitrate-nitrogen concentration in the non-rhizosphere soil (P<0.05), but biochar addition weakened the difference. Biochar addition decreased the nitrate-nitrogen concentration in the rhizosphere soil under the same drip irrigation patterns. In the D treatment, biochar significantly decreased the number of copies of AOA, AOB, and nirK genes in the non-rhizospheric soil, and AOA gene copies in the rhizospheric soil (P<0.05); however, there was an increase in the number of copies of AOB and nirK genes in the rhizospheric soil of the D and ID treatments (P<0.05). Based on the structural equation model (SEM), in the non-rhizospheric and rhizospheric soils, pH and electrical conductivity were the environmental factors with the greatest influence on the ammonium-nitrogen and nitrate concentrations, respectively, and the gene copy number of AOB was the biotic factor with the greatest influence on the nitrate-nitrogen concentration. Based on PICRUSt, the γ-Proteobacteria contributed mostly to ammonia monooxygenase gene (K10945) expression, whereas the α-Proteobacteria, especially the rhizobia members, contributed mostly to nitrite reductase gene (K00368) expression. Biochar addition regulated the bacterial community structure that participated in K10945 gene expression in the non-rhizospheric soil and K00368 gene expression in the rhizospheric soil (P<0.05). Overall, biochar addition contributed more to nitrate-nitrogen and microbial mineral nitrogen-transformation processes in the agricultural soil than did the drip irrigation patterns.