Next Article in Journal
Environmental Effects of Driver Distraction at Traffic Lights: Mobile Phone Use
Previous Article in Journal
Multi-Objective Considered Process Parameter Optimization of Welding Robots Based on Small Sample Size Dataset
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Potential Use of Subsurface Drip Irrigation Systems in Landscape Irrigation under Full and Limited Irrigation Conditions

Department of Agricultural Structures and Irrigation, Agricultural Faculty, Selcuk University, Konya 42100, Türkiye
Sustainability 2023, 15(20), 15053; https://doi.org/10.3390/su152015053
Submission received: 26 September 2023 / Revised: 7 October 2023 / Accepted: 17 October 2023 / Published: 19 October 2023

Abstract

:
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.

1. Introduction

Green areas are important living spaces in cities. The importance of green areas increases even more for people who want to get away from busy business and city life in these areas, to stay away from stress, to take healthy, fresh air, and to have a pleasant time alone or with their families [1,2,3]. Green areas make great contributions to cities in terms of aesthetics, spaciousness, reducing the effects of some gases that cause air pollution, and creating an environment that people can enjoy. The need for green space in cities is directly proportional to population growth. The quality of urban life and the level of development of cities are closely related to the amount of green space the city has, as well as the amount of green space per capita. Since Konya province is growing rapidly, the amount of green space is increasing with the increasing population and settlements. Therefore, it is estimated that the amount of water to be used for irrigation of green areas will be higher than that used today [4].
Perennial grass species are widely used in the creation of green areas and parks. There are over 1200 grass species and varieties. Characteristics such as degree of coverage, length of growing season, tolerance to drought, type, and color are taken into consideration while selecting grass species [5]. In addition to all these features, varieties that are resistant to trampling are preferred, especially for grass species to be used in sports and recreation fields and parks. Turfgrass can be divided into two groups: cool-season and warm-season grasses. Cool-season grasses (Kentucky bluegrass, perennial ryegrass, tall fescue, Poa pratensis, Festuca rubra, Lolium perenne, Festuca arundinacea, etc.) are more cold-tolerant and exhibit a longer growing season than warm-season grasses (Bermudagrass, blue grama, buffalograss, zoysiagrass, etc.). Cold tolerance is usually the first desirable characteristic when selecting perennial plants, whether it is turfgrass or bushes and trees [6]. The water required for irrigation of landscape areas is generally supplied from the city’s drinking and utility water networks. Konya Province has quite limited water resources and low precipitation levels. Therefore, efficient use of irrigation water is essential, especially in green areas of the province [7].
Plant water consumption should be well understood for efficient use of irrigation water. Plant water consumption is also closely related to the development of irrigation projects [8,9,10]. Irrigation, briefly, is the balanced and controlled supply of water required for the development of plants but not met by natural precipitations in plant root zones. Irrigation plays a great role in the design and maintenance of landscape areas. For plants to survive, the required amount of water must be delivered through a system. The location of the area to be irrigated, current water resources, and plant characteristics should be taken into consideration while selecting an irrigation system. Improper system selection or inappropriate system design can lead to significant waste and loss of water [11].
In the irrigation of landscape areas, water is delivered to the plants at regular intervals, not all at once. Therefore, considering both labor cost and practicality, the most suitable irrigation systems should be preferred for irrigation of these areas [12]. In the planning of irrigation systems, a technical irrigation program and project should be prepared by taking cropping patterns, plant water consumption, the amount of irrigation water needed, water quality, and soil properties into consideration. After determining the actual water consumption, irrigation water needs, irrigation time, and irrigation intervals, monthly and seasonal irrigation water needs should be calculated. The most suitable irrigation system will then be designed and implemented accordingly [13].
The pop-up (fixed sprinkler) irrigation method is generally used for the irrigation of green areas. With this system, green areas are irrigated from above, which is affected by climate factors and causes water loss. In addition, system equipment is destroyed by people. In recent years, sub-surface drip irrigation systems, which have eliminated these problems, have started to be used for irrigation of lawns and landscape areas (Figure 1).
A sub-surface drip irrigation system was first introduced in 1959. In the 1980s, scientific research increased rapidly and was put into practice [14,15,16,17,18,19]. With a sub-surface drip irrigation system, the above-mentioned costs will be avoided, water losses will be reduced, and optimum development will be achieved with timely and adequate irrigation. The use of subsurface drip irrigation systems has been increasing and yields various benefits, including the ability to apply water close to the plant root system without wetting the soil surface, which results in small losses by evaporation and thus high application efficiency [20,21]. Because the drip lines are not exposed to the surface, mechanical damage and solar radiation are minimized, facilitating crop management practices and increasing the longevity of the system [22]. Sub-surface irrigation systems apply water directly to the root zone, thereby avoiding problems such as overspray, runoff, wind drift, and human exposure [23].
Deficit irrigation practices are becoming more and more important in regions with deficits or limited water resources [24,25]. Since there is no yield reduction problem in the irrigation of green areas, deficit irrigations are becoming more popular. Deficit irrigations are also popular since drinking and utility water are used for the irrigation of green areas in several cities. Therefore, deficits in irrigation water in a way that does not impair the quality and performance standards of the plants are highly significant for good water management [8].
Crop evapotranspiration is mostly estimated from the correlations between evaporations measured from class-A pans and reference crop evapotranspiration [26]. Since climate factors effective on pan evaporation are also effective on crop water consumption in the same fashion, quite accurate results can be achieved with this method. This method of estimation is commonly used worldwide [27,28].
The irreversibility of global climate change brings about serious reductions in freshwater resources. At the same time, the increasing world population and corresponding increase in water demand limit the use of water in crop production. The water and drought cause serious stress for both cool and warm-season grass species. While grass fields are an important source of recreation in many world capitals, increasing drought may cause these fields to become increasingly idle and perhaps decrease the national happiness index. These stress conditions can occur alone, or it is possible for many factors to come together. This situation can cause irreversible damage [29].
Nowadays, the importance of water and irrigation is increasing with decreasing water availability. In this sense, irrigation systems and irrigation durations also play a great role in the irrigation of central refuges and parks. In this study, the potential use of sub-surface drip irrigation methods in the irrigation of green areas was investigated, and the sub-surface drip irrigation method was compared with the fixed sprinkler irrigation method (pop-up). The effects of different system designs and irrigation programs on irrigation parameters and plant characteristics were also determined.

2. Materials and Methods

This study was conducted in parks and green areas within the borders of the Selçuklu district of Konya province (Figure 2).
Selçuklu district is located between 36°52′ North latitudes and 32°29′ East longitudes. Selçuklu is the largest district of Konya province in terms of population and development [30]. The area of the district is 2.056 km², and the altitude is 1020 m. The total area of green areas in Selçuklu District is 13,276.242m², and the active green area is 6928.130 m². The population is 648.850 people. Considering the district’s total active green area availability and population, there is 10.68 m² of active green area per person. This value is greater than the amount of green space per capita in many provinces and districts in Turkey.
Konya province has a semi-arid climate and is among the provinces with the least precipitation. The average annual rainfall is 322.4 mm, and it is one of the regions with the least rainfall in Turkey.

2.1. Experimental Design and Treatments

For the present experiments, a 1300 m2 area was surrounded by wires, and a total of 570 m2 of grass cover was generated (Figure 3). In the research, the grass seed mixture used by Selçuklu Municipality to create grass areas in parks and green areas was used. The grass seed mixture was sown so as to have 55–60 g of seeds per m2. The seed mixture is composed of 40% Loliumperenne (British grass), 20% Festucarubracommutata (Common red festuca), 30% Festucarubrarubra (red festuca), and 10% Poapratensis (blue grass). Ammonium sulfate (21% nitrogen, 30 g/m2) was applied as a fertilizer.
Sub-surface drip irrigation and sprinkler irrigation (pop-up) methods were used in the present experiments. The sub-surface drip irrigation method was established with two different lateral depths (0.10 and 0.15 m) and three different lateral spacings (0.40, 0.60, and 0.80 m). Water deficits were also applied in both methods (100, 80, and 60% of cumulative evaporation from Class-A pan). Sub-surface drip irrigation treatments were applied on 54 plots (3 lateral spacings × 2 lateral depths × 3 water deficits × 3 replicates), and sprinkler irrigation treatments were applied on 9 plots (3 water deficits × 3 replicates). The total number of plots was 63 (Figure 4, Table 1). Each plot had a size of 9 m2 (3 × 3 m). Experiments were conducted in a randomized block design with three replications; 2 m spacing was provided between the blocks and 1 m between the plots.
Fixed sprinkler (pop-up) and sub-surface drip irrigation systems were established for irrigation. Spray pop-up heads, which have a 0.11 m3 h−1 flow rate and 3 m irrigation radius with a 210 kPa operating pressure, were used in each plot. In the sub-surface drip irrigation system, 15.5 mm PE laterals with 1.0 L h–1 in-line drippers spaced 40 cm apart and operating at 100 kPa pressure were installed.
Soil samples were taken from the 0–30 cm soil profile of experimental fields, and soil physico-chemical characteristics are provided in Table 2. As can be seen from Table 2, the soil texture was sandy clay-loam (SCL). Soil salinity was measured at 0.52 dS m−1. Soil salinity measurements were made in saturation extract with a conductivity meter. A double-ring infiltrometer was used to measure the soil infiltration rate. The infiltration rate value for the experimental site was measured at 7.8 mm ha−1.
Irrigation water was supplied from a groundwater well in experimental fields, and irrigation water quality parameters are provided in Table 3. As can be seen from Table 3, irrigation water can be classified as class C2 S1 [31].

2.2. Plant Water Consumptions

Soil moisture was measured with the TDR 300 device. The gravitational method was used for calibration of the TDR device. Plant water consumption was calculated using the following water-budget equation [32].
E T = I + R D p + C p R f ± S
where ET indicates plant water consumption (mm); I indicates the amount of irrigation water to be applied (mm); R indicates effective precipitation (mm); Dp indicates deep percolation (mm); Cp indicates capillary rise; Rf indicates surface runoff; ΔS indicates change in soil moisture (mm); Dp values were checked with the use of TDR 300 and calculated gravimetrically from the soil samples taken from 30 and 45 cm soil depths before and after the irrigations. Since experiments were conducted under controlled conditions, Cp and Rf values were neglected.

2.3. Amount of Irrigation Water to Be Applied

The amount of irrigation water to be applied to each plot was calculated using the following equation [33].
I = A × E p a n × K p c × P
where I indicates the amount of irrigation water to be applied (L); Epan indicates total evaporation from Class-A pan between successive irrigations (mm); Kpc indicates plant-pan coefficient; and P indicates wetting ratio (100%).
Irrigations were initiated when 30% of the available moisture at field capacity was depleted. In the other irrigations, a certain percentage of 2-day evaporation from the Class-A pan was applied. Irrigation water was passed through water meters installed at the entrance of each plot.

2.4. Plant Observations

Germination and emergence were checked 8 days after seeding. For homogenous emergence and initial set-up, sprinkler irrigation was applied to all plots. Plant heights were measured just before mowing from 10 different locations on each plot with a ruler. To prevent the negative effects of surface roughness, measurements were taken from the same locations on each plot with a piece of wood put on the soil surface. Mowing is usually performed when the grass height reaches about 10–12 cm, and mowing is practiced 4–5 cm above ground. Mowed grass was weighed in each time. At the end of the irrigation season, a profile pit was opened in each plot to measure root lengths with a ruler. The quality of the grass is determined visually. Therefore, periodic photographs were taken.

3. Results and Discussion

3.1. Irrigation Water Quantities

Irrigations were initiated in mid-April and terminated in mid-October. A total of 87 irrigations were practiced in 2017 and 83 irrigations in 2018. The amount of irrigation water applied in each treatment is provided in Table 4.
In both years, the greatest amount of irrigation water was applied in YS1 treatments (100% sprinkler irrigation) (1111.03 and 1158.39 mm) and the lowest in S13–S18 treatments (60% sub-surface drip irrigation) (579.96 and 604.68 mm). Under full irrigation conditions, approximately 15% more irrigation water was applied in YS1 treatments than in S1–S6 treatments in both years. This ratio is very important for the sustainability of urban water resources, especially in arid and semi-arid regions such as the research area. In all treatments, the greatest amount of irrigation water was applied in July and the least in October. Changes in monthly irrigation water quantities are presented in Figure 5.
Ref. [8] conducted a study for the landscapes of Konya central town and reported the average amount of irrigation water applied through the sprinkler irrigation system as 803.33 mm. In a similar study, Ref. [34] reported the average amount of water applied through a sub-surface drip irrigation system as 712.15 mm. Ref. [35] conducted a study under Tekirdağ provincial conditions and reported the amount of irrigation water applied as between 238.5 and 501.6 mm for cool-season grass species and as between 140.7 and 416.7 mm for warm-season grass species. In a similar study conducted in the same region, Ref. [36] reported the amount of irrigation water applied as between 275.3 and 523.5 mm for cool-season grass species and as between 186.2 and 423.8 mm for warm-season grass species. Ref. [37] conducted a study to determine the effects of different irrigation levels on ET and the quality characteristics of turfgrass. In this study, four different irrigation treatments were examined: 100% (S1), 75% (S3), and 50% (S4) of the evaporation measured in Class-A Pan; the S2 irrigation treatment represented the irrigation level practiced by the golf course management. According to the trial subjects (S1, S2, S3, and S4), respectively, they applied 780.3, 690.0, 587.5, and 391.8 mm of irrigation water.

3.2. Plant Water Consumptions

While desired plant development was achieved in full irrigation treatments (100%) since plants were not exposed to water stress, some developmental problems were encountered in deficit irrigation treatments (80 and 60%). Since there is always available moisture at around field capacity levels in full irrigations, a healthy development was seen. Then, healthy plants had better leaf development and greater plant water consumption. However, there was not sufficient moisture within the root zone in deficit irrigations. Such a deficit in water recessed plant growth and development and reduced plant water consumption [7]. Monthly plant water consumptions are provided in Table 5.
In both years, the greatest water consumption was seen in July and the least in April and October (Figure 6). In terms of experimental treatments, the greatest water consumption was seen in full irrigations (S1–S6 treatments, 1034.6 and 1055.4 mm; YS1 treatments, 1094.3 and 1098.7 mm) and the least in 60% deficit irrigations (S13–S18 treatments, 657.6 and 662.1 mm; YS3 treatments, 688.5 and 686.9 mm). Lateral spacing and depths did not have significant effects on plant water consumption in sub-surface drip irrigation treatments.
Ref. [8] reported the water consumption of grass species as 771 mm for full irrigations, 657 mm for 20% deficits, 563 mm for 40% deficits, and 459 mm for 60% deficits. Ref. [34] used sub-surface drip irrigations for landscape irrigations under Konya provincial conditions and reported the average water consumption of grass species as 766.56 mm. Ref. [35] used sprinkler irrigation in Tekirdag province and reported average water consumptions of grass species as between 317.8 and 610.5 mm for cool-season species and as between 211.0 and 488.8 mm for warm-season species. Ref. [38] conducted a similar study with the sub-surface drip irrigation method in the same region and reported average water consumptions as between 260.2 and 382.7 mm for cool-season species and as between 180.4 and 357.9 mm for warm-season species. Ref. [36] used sprinkler irrigation in the same region and reported water consumptions as between 521.9 and 754.8 mm for cool-season species and as between 521.5 and 590.1 mm for warm-season species. Ref. [37] conducted a study to determine the effects of different irrigation levels (100% (S1), 75% (S3), and 50% (S4) of the evaporation measured in Class-A Pan on ET and quality characteristics of turfgrass, which reported plant water consumptions of 895.7, 809.0, 710.7, and 524.7, respectively. In the research conducted by [39] using a lysimeter to determine the actual and reference plant water consumption and related plant coefficients of cold-climate grasses between April and October in the north of Colorado, water consumption of grass plants during vegetation was measured at 736 mm.

3.3. Effects of Different Irrigation Programs on Plant Characteristics

As a measure of healthy development, germination, and coverage, plant height, weight, appearance, and root lengths were measured. As it was indicated before, sowing was performed in 2016, and completion of root and vegetative development was awaited. Thus, measurements were taken in 2017 and 2018. Measurements were initiated in mid-April and terminated in mid-October.

3.4. Germination

The grass mixture was sown on 20 May 2016. Germination and emergence started 8 days after sowing (28 May 2016). About 50% emergence was seen on 4 June 2016 and 100% on 14 June 2016 (Figure 7). Emergence and coverage were realized almost at the same time in all plots. For homogeneous germination, emergence, and coverage, all plots were initially irrigated with a sprinkler (pop-up) irrigation system.

3.5. Plant Height

Since the plant is expected to reach a certain height for mowing, the time taken to reach a certain height is taken as a basis instead of the plant height. Plant height-related data are given in Table 6 and Table 7. Plant height development was found to be close to each other with the effect of spring precipitations in all plots in the first days of measurements. Grass height showed a regular improvement during the experiment in S1, S2, S3, S4, S5, S6, and YS1 treatments with full irrigation. Among these treatments, grass heights increased more homogeneously in YS1, S1, and S2 treatments as compared to others (S3, S4, S5, and S6), mostly because of different lateral spacings.
Although plant heights were homogeneous in S1 and S2 treatments without water deficits and irrigated with the sub-surface drip irrigation method, there was a slight difference in mowing weights. Such a difference was due to plant height. S1 treatments had greater mowing weights than S2 treatments in both 2017 and 2018. In YS1 treatments irrigated with the sprinkler irrigation method, plant height increased more than in S1 treatments irrigated with the sub-surface drip irrigation method, so both the number of mows and mowing weights were higher than in S1 treatments.
In water deficit treatments, the development of plant height has slowed down over time due to water deficits, and the number of mows has also decreased. It took more time for the plant height to reach mowing height in the S17 and S18 treatments irrigated with the sub-surface drip irrigation method, and mowing weights were much less as compared to the S1 and S2 treatments. The same situation was encountered in YS3 treatments, which were given the same amount of water and irrigated with the sprinkler irrigation method. It was reported in previous studies that plant water consumption increased with increasing plant heights [6,40,41,42,43]. Similar findings were seen in the present study, and water deficits delayed plant height developments.

3.6. Number of Mows and Mowing Weights

The first mows at the beginning of the irrigation season could be made when the grass height was 13–15 cm, with the effect of spring rains. Since the growth rate of the grass plant was different based on experimental treatments, mowing dates also varied. The number of mows, mowing dates, mowing heights, and weights are given in Table 6 and Table 7. In 2017, the highest number of mows was 10 with a mowing weight of 3.031 g m−2 (YS1 treatment), the least number of mows was 5, and the least mowing weight was 984 g m−2 (S18 treatments). The number of mows was 9 in S1, S2, S3, S4, S5, and S6 treatments, which were irrigated with the sub-surface drip irrigation method without water deficits. In 80% deficit irrigation treatments, the number of mows was 7 in S7 and S8 treatments and 6 in S9, S10, S11, and S12 treatments. In 60% deficit irrigation treatments, the number of mows was 6 in S13, S14, S15, S16, S17, and S18 treatments. In 2018, the highest number of mows (11) and mowing weight (3.367 g m−2) were obtained from YS1 treatments (100% sprinkler irrigation). The least number of mows (6) and the least mowing weight (1.114 g m−2) were obtained from S18 (60% sub-surface drip irrigation) treatments. In sub-surface irrigation treatments, the number of mows was 10 in S1, S2, S3, S4, S5, and S6 treatments, 9 in S7 and S8 treatments, 8 in S9, S10, S11, and S12 treatments, 7 in S13, S14, S15, and S16 treatments, and 6 in S17 and S18 treatments.
In general, the number of mows and mowing weights was greater in 2018 than in 2017 because of the precipitation in 2018. In both years, the first mowing weights were close to each other in all treatments. Then, mowing weights decreased with decreasing irrigation water quantities. In sub-surface drip irrigation treatments with the same irrigation water quantity, the number of mows and mowing weights decreased with increasing lateral spacing and lateral depths (Figure 8).
Turfgrass irrigated with larger irrigation amounts showed higher dry matter production. It is important to highlight the positive correlation between turfgrass quality and daily dry matter production in irrigated turfgrass [44]. Ref. [8] conducted a landscape irrigation study with sprinkler (pop-up) irrigation methods (100, 60, 50, and 40% of total evaporation from Class-A pan) and reported the total number of mows as 11 for full irrigation, 7 for 60% irrigation, 5 for 50% irrigation, and 4 for 40% irrigation treatments. Total mowing weight was reported as 2.931 g m−2 for full irrigation, 1.648, 1.059, and 857 g m−2 for 60, 50, and 40% irrigations, respectively. [34] conducted a study with the sub-surface irrigation method and reported the total number of mows as 11 and the total mowing weight as 2.84 g m−2.

3.7. Root Lengths

Since sufficient moisture was maintained within the root zone in subsurface drip irrigations, roots did not go much below the drip lines (Figure 7). In 100% sub-surface drip irrigations, root lengths were predominantly around 10–11 cm in S1, S3, and S5 treatments with a lateral depth of 10 cm and around 15–16 cm in S2, S4, and S6 treatments with a lateral depth of 15 cm. In 80% sub-surface irrigations, roots were mainly located around the lateral lines and went 3–5 cm below the lines in S7, S9, and S11 treatments with a lateral depth of 10 cm; went down till 20 cm and slightly till 22–25 cm in S8, S10, and S12 treatments with a lateral depth of 15 cm. In 60% sub-surface drip irrigations, roots were again dominantly located around the drip lines, and some went 5–7 cm below the lines and reached about 17 cm in S13, S15, and S17 treatments with a lateral depth of 10 cm; they went down to 25 cm in S14, S16, and S18 treatments with a lateral depth of 15 cm (Figure 7).
In sprinkler (pop-up) irrigations, grass roots were dominantly around 10 cm in YS1 treatments (100% sprinkler irrigation); around 12 cm and some 15 cm in YS2 treatments (80% sprinkle irrigations); and dominantly around 15–16 cm and some around 20 cm in YS3 treatments (60% sprinkler irrigations) (Figure 9).
Ref. [34] conducted a landscape irrigation study with the subsurface drip irrigation method and indicated that roots did not go much below the drip lines and reached up to 10–12 cm underground. Ref. [45] reported that roots were shallow in areas where water was not limited, whereas under drought conditions, roots developed downward in order to take up water. Ref. [37] conducted a study to determine the effects of different irrigation levels applied to golf courses on some quality characteristics of turf grass. As a result of the research, they reported that in conditions where water is not limited, the roots are shallow, and therefore their weight is low. According to some researchers, there was a relationship between irrigation amount and root development, depending on the species and varieties [46,47]. In general, no significant change in rooting was observed at different irrigation amounts between 60% and 100% ETa [48,49]. However, under a more severe deficit irrigation regime (20% ETa), Ref. [48] observed a greater number and length of roots, but this was accompanied by a reduction in turfgrass quality.

3.8. Visual Appearance of Experimental Plots

In terms of color and quality, 100% sub-surface drip irrigations (S1 with 40 cm lateral spacing and 10 cm lateral depth and S2 with 40 cm lateral spacing and 15 cm lateral depth) maintained appealing color and homogeneous coverage throughout the irrigation season. S1 treatments were found to be better than S2 treatments. Again, 100% sprinkler irrigation (YS1) has well-maintained color and coverage. When these two different methods were compared, S1 was found to be more advantageous in terms of the number of mows and the amount of irrigation water applied (Figure 10).
Deficit irrigations (S7–S18, YS2, and YS3) yielded poorer color and coverage than the full irrigations. Both grass quality and coverage rates decreased with increasing water deficits. Dry-outs were encountered at the highest water deficits (60% irrigations). Such dry-outs were even more remarkable in 2018 because water deficits have been applied since the beginning of experiments. Grass quality and coverage also decreased with increasing lateral spacing and depth of sub-surface drip irrigations (Figure 10).
Differences in turfgrass quality among species and varieties became more noticeable as the irrigation amount was reduced. In contrast to most agricultural systems, for turfgrass, any reductions in shoot growth are perceived to be beneficial, as long as visual and functional quality are not significantly sacrificed [50]. In general, during the growing season, average visual turf quality can be maintained at an acceptable level through deficit irrigation (up to 40% ETa), while turfgrass quality can be achieved with irrigation above 60–80% ETa [44].
Refs. [8,51] indicated that irrigation water was the primary criterion to meet quality and performance standards for green areas; thus, sufficient water should be supplied for the maintenance of color and coverage in dry regions. Refs. [35,36,38] irrigated cool and warm-season grass species with sub-surface drip and sprinkler irrigation methods and indicated that plant growth and quality parameters were significantly influenced by irrigation methods and applied irrigation water quantities. Similar findings were also reported by [52].

4. Conclusions

The potential use of the sub-surface drip irrigation method in irrigation of green areas 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). The greatest water consumption and irrigation water quantities were seen in July, with almost equal amounts of water applied in 100% sub-surface and sprinkler irrigations. Although deficit irrigations reduced the amount of irrigation water applied, they resulted in changes in grass quality, color, appearance, and homogeneous coverage. In terms of color and coverage, 100% sub-surface drip irrigations (S1 with 40 cm lateral spacing and 10 cm lateral depth and S2 with 40 cm lateral spacing and 15 cm lateral depth) maintained appealing color and homogeneous coverage throughout the irrigation season. S1 treatments were found to be better than S2 treatments. Again, 100% sprinkler irrigation (YS1) has well-maintained color and coverage. When these two different methods were compared, S1 was found to be more advantageous in terms of the number of mows and the amount of irrigation water applied. Since appealing color and homogenous coverage are the principal concerns and yield (mowing weight) is not the primary criteria in landscape irrigations, sub-surface drip irrigations with 40 cm lateral spacing and 10 cm lateral depth could be used in landscape irrigations in Konya province and similar ecologies.

Funding

Selçuk University Scientific Research Projects Coordination Office, project number 16201033.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Acknowledgments

This study was derived from a Ph.D. Thesis entitled “Investigation of Usability of Subsurface Drip Irrigation Method for Green Fields” by my student Selman KAYA, with whom I conducted this study, who passed away in October 2021. May God rest his soul in heaven. Thanks are extended to Selçuk University Scientific Research Projects Coordination Office for supporting this thesis as a research project (16201033) and Selçuklu Municipality for allocating land for experiments.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Hilaire, R.S.; Arnold, M.A.; Wilkerson, D.C.; Devitt, D.A.; Hurd, B.H.; Lesikar, B.J.; Zoldoske, D.F. Efficient water use in residential urban landscapes. HortScience 2008, 43, 2081–2092. [Google Scholar] [CrossRef]
  2. Serena, M.; Velasco-Cruz, C.; Friell, J.; Schiavon, M.; Sevostianova, E.; Beck, L.; Salllenave, R.; Leinauer, B. Irrigation scheduling technologies reduce water use and maintain turfgrass quality. Agron. J. 2020, 112, 3456–3469. [Google Scholar] [CrossRef]
  3. Spronken-Smith, R.A.; Oke, T.R.; Lowry, W.P. Advection and the surface energy balance across an irrigated urban park. Int. J. Climatol. 2000, 20, 1033–1047. [Google Scholar] [CrossRef]
  4. Kaya, S. The Irrigation Methods Applied to the Green Fields of Konya-Selçuklu District and Sample Sancaktepe Park. Master’s Thesis, Selçuk University, Graduate School of Natural and Applied Sciences, Konya, Türkiye, 2013. [Google Scholar]
  5. Orta, A. Irrigation in Recreation Areas; Nobel Academic Publishing: Ankara, Türkiye, 2017. [Google Scholar]
  6. Orta, A.H.; Todorovic, M.; Ahi, Y. Cool-and Warm-Season Turfgrass Irrigation with Subsurface Drip and Sprinkler Methods Using Different Water Management Strategies and Tools. Water 2023, 15, 272. [Google Scholar] [CrossRef]
  7. Şahin, M.; Kara, M. Determination of Evapotranspiration and Crop Coefficient for Grass under Different Irrigation Application in Konya Centrum. Selçuk J. Agric. Food Sci. 2005, 19, 135–145. [Google Scholar]
  8. Şahin, M. The Problems Faced in Irrigation of the Park and Green Areas and Suggestions to Solve Them in Konya Centrum. Ph.D. Thesis, Selçuk University, Graduate School of Natural and Applied Sciences, Konya, Türkiye, 2005. [Google Scholar]
  9. Kieffer, D.; Campbell, T. Effect of sub-surface drip irrigation and shade on soil moisture uniformity in residential turf. In Proceedings of the 30th Annual Irrigation Show San Antonio, San Antonio, TX, USA, 2–4 December 2009. [Google Scholar]
  10. Kırnak, H.; Gökalp, Z.; Demir, H.; Kodal, S.; Yıldırım, E. Paprika pepper yield as affected by different irrigation levels. J. Agric. Sciences. J. Agric. Sci. 2016, 22, 77–88. [Google Scholar] [CrossRef]
  11. Zhu, X.; Xu, Z.; Liu, Z.; Liu, M.; Yin, Z.; Yin, L.; Zheng, W. Impact of dam construction on precipitation: A regional perspective. Mar. Freshw. Res. 2022, 74, 877–890. [Google Scholar] [CrossRef]
  12. Liu, Z.; Xu, J.; Liu, M.; Yin, Z.; Liu, X.; Yin, L.; Zheng, W. Remote sensing and geostatistics in urban water-resource monitoring: A review. Mar. Freshw. Res. 2023, 74, 747–765. [Google Scholar] [CrossRef]
  13. Yin, L.; Wang, L.; Keim, B.D.; Konsoer, K.; Yin, Z.; Liu, M.; Zheng, W. Spatial and wavelet analysis of precipitation and river discharge during operation of the Three Gorges Dam, China. Ecol. Indic. 2023, 154, 110837. [Google Scholar] [CrossRef]
  14. Camp, C.R. Subsurface drip irrigation: A review. Trans. ASAE Pap. 1998, 41, 1353–1367. [Google Scholar] [CrossRef]
  15. Camp, C.R.; Lamm, F.R. Irrigation systems, subsurface drip. Encycl. Water Sci. 2003, 560–564. [Google Scholar] [CrossRef]
  16. Leinauer, B.; Makk, J. Effect of Irrigation Type and Rootzone Material on Irrigation Efficiency, Turfgrass Quality, and Water Use on Putting Greens in the Southwest; USGA Turfgrass and Environmental Research Summary: New York, NY, USA, 2005. [Google Scholar]
  17. Lamm, F.R.; Camp, C.R. 13. Subsurface drip irrigation. Dev. Agric. Eng. 2007, 13, 473–551. [Google Scholar] [CrossRef]
  18. Lamm, F.R.; Bordovsky, J.P.; Schwankl, L.J.; Grabow, G.L.; Enciso-Medina, J.; Peters, R.T.; Colaizzi, P.D.; Trooien, T.P.; Porter, D.O. Subsurface drip irrigation: Status of the technology in 2010. Trans. ASABE 2012, 55, 483–491. [Google Scholar] [CrossRef]
  19. Ayars, J.; Fulton, A.L.A.N.; Taylor, B. Subsurface drip irrigation in California -Here to stay? Agric. Water Manag. 2015, 157, 39–47. [Google Scholar] [CrossRef]
  20. Ayars, J.E.; Phene, C.J.; Hutmacher, R.B.; Davis, K.R.; Schoneman, R.A.; Vail, S.S.; Mead, R.M. Subsurface drip irrigation of row crops: A review of 15 years of research at the Water Management. Agric. Water Manag. 1999, 42, 1–27. [Google Scholar] [CrossRef]
  21. Fan, W.; Li, G. Effect of soil properties on hydraulic characteristics under subsurface drip irrigation. IOP Conf. Ser. Earth Environ. Sci. 2018, 121, 052042. [Google Scholar] [CrossRef]
  22. Martínez, J.; Reca, J. Water use efficiency of surface drip irrigation versus an alternative subsurface drip irrigation method. J. Irrig. Drain. Eng. 2014, 140, 04014030. [Google Scholar] [CrossRef]
  23. Leinauer, B.; Devitt, D.A. Irrigation science and technology. In Agronomy Monograph 56; Horgan, B., Stier, J., Bonos, S., Eds.; ASA, CSSA, and SSSA: Madison, WI, USA, 2013; pp. 1075–1133. [Google Scholar] [CrossRef]
  24. English, M.J.; Solomon, K.H.; Hoffman, G.J. A paradigm shift in irrigation management. J. Irrig. Drain. Eng. 2002, 128, 267–277. [Google Scholar] [CrossRef]
  25. Kırda, C. Deficit irrigation scheduling based on plant growth stages showing water stress tolerance. In Deficit Irrigation Practice; Water reports 22; FAO: Rome, Italy, 2002; pp. 1–3. [Google Scholar]
  26. Doorenbos, J.; Pruitt, W.O. Guidelines for Predicting Crop Water Requirements; (Irrigation and drainage paper 24); FAO: Rome, Italy, 1977. [Google Scholar]
  27. Irmak, S.; Haman, D.; Jones, J.W. Evaluation of Class A pan coefficients for estimating reference evapotranspiration in humid location. J. Irrig. Drain. Eng. 2002, 128, 153–159. [Google Scholar] [CrossRef]
  28. Kızıloğlu, F.M.; Şahin, U.; Kuşlu, Y.; Tunç, T. Determining water–yield relationship, water use efficiency, crop and pan coefficients for silage maize in a semiarid region. Irrig. Sci. 2008, 27, 129–137. [Google Scholar] [CrossRef]
  29. Huang, B.; DaCosta, M.; Jiang, Y. Research advances in mechanisms of turfgrass tolerance to abiotic stresses: From physiology to molecular biology. Crit. Rev. Plant Sci. 2014, 33, 141–189. [Google Scholar] [CrossRef]
  30. Selçuklu Municipality. Available online: http://www.selcuklu.gov.tr/ilce-tarihi (accessed on 19 February 2019).
  31. Richards, L.A. Diagnosis and Improvement of Saline and Alkali Soils; No:60; US Government Printing Office: Washington, DC, USA, 1954; p. 160.
  32. James, L.G. Principles of Farm Irrigation System Design; John Wiley & Sons: New York, NY, USA, 1988; p. 543. [Google Scholar]
  33. Kanber, R. Irrigation of first and second crop peanuts using open water surface evaporation in Çukurova conditions. Soilwater Res. Enst. Publucations 1984, 114, 64–93. [Google Scholar]
  34. Şahin, M.; Çiftçi, N.; Gökalp, Z. Sub-Surface Drip Irrigation Method for Lawn Irrigation, For Agrıcasıa’2013, 1st Central Asia Congress on Modern Agricultural Techniques and Plant. Soil-Water J. 2013, 2, 1281–1290. [Google Scholar]
  35. Bezirgan, S. Irrigation Scheduling of Cool and Warm Season Turfgrass Irrigated with Sprinkler Irrigation Method. Master’s Thesis, Tekirdağ Namık Kemal University, Graduate School of Natural and Applied Sciences, Department of Biosystem Engineering, Süleymanpaşa/Tekirdağ, Türkiye, 2018. [Google Scholar]
  36. Türk, B. Evapotranspiration and Irrigation Scheduling of Cool and Warm Season Turfgrasses Irrigated with Sprinkler Irrigation Method. Master’s Thesis, Tekirdağ Namık Kemal University, Graduate School of Natural and Applied Sciences, Department of Biosystem Engineering, Süleymanpaşa/Tekirdağ, Türkiye, 2019. [Google Scholar]
  37. Baştuğ, R.; Büyüktaş, D. The effects of different irrigation levels applied in golf courses on some quality characteristics of turfgrass. Irrig. Sci. 2003, 22, 87–93. [Google Scholar] [CrossRef]
  38. Ayanoğlu, H.; Orta, A.H. Irrigation Scheduling of Cool and Warm Season Turfgrass Irrigated with Sub-Drip Irrigation Method. J. Tekirdag Agric. Fac. 2019, 16, 362–381. [Google Scholar]
  39. Mecham, B.Q. Scheduling Tufgrass Irrigation by Various ET Equations. Evapotranspiration and Irrigation Scheduling. In Proceedings of the International Conference, San Antonio, TX, USA, 26–29 June 1996; pp. 245–249. [Google Scholar]
  40. Biran, I.; Bravdo, B.; Bushkin-Harav, I.; Rawitz, E. Water Consumption and Growth Rate of 11 Turfgrasses as Affected by Mowing Height, Irrigation Frequency, and Soil Moisture. Agron. J. 1981, 73, 85–90. [Google Scholar] [CrossRef]
  41. Feldhake, C.; Danielson, R.; Butler, J. Turfgrass evapotranspiration. 11. Responses to deficit irrigation. Agron. J. 1984, 76, 85–89. [Google Scholar] [CrossRef]
  42. Fry, J.D.; Butler, J.D. Responses of tall and hard fescue to deficit irrigation. Crop Sci. 1989, 29, 1536–1541. [Google Scholar] [CrossRef]
  43. Hejl, R.W.; Wherley, B.G.; Fontanier, C.H. Long-term performance of warm-season turfgrass species under municipal irrigation frequency restrictions. HortScience 2021, 56, 1221–1225. [Google Scholar] [CrossRef]
  44. Gómez-Armayones, C.; Kvalbein, A.; Aamlid, T.S.; Knox, J.W. Assessing evidence on the agronomic and environmental impacts of turfgrass irrigation management. J. Agron. Crop Sci. 2018, 204, 333–346. [Google Scholar] [CrossRef]
  45. Açıkgöz, E. Tarımsal Ekoloji; Uludağ Üniversitesi: Bursa, Türkiye, 1995. [Google Scholar]
  46. Bowman, D.C.; Devitt, D.A.; Engelke, M.C.; Rufty, T.W. Root architecture affects nitrate leaching from bentgrass turf. Crop Sci. 1998, 38, 1633–1639. [Google Scholar] [CrossRef]
  47. Sinclair, T.R.; Schreffler, A.; Wherley, B.; Dukes, M.D. Irrigation frequency and amount effect on root extension during sod establishment of warm-season grasses. HortScience 2011, 46, 1202–1205. [Google Scholar] [CrossRef]
  48. Fu, J.; Fry, J.; Huang, B. Tall fescue rooting as affected by deficit irrigation. HortScience 2007, 42, 688–691. [Google Scholar] [CrossRef]
  49. Su, K.; Bremer, D.J.; Keeley, S.J.; Fry, J.D. Effects of high temperature and drought on a hybrid bluegrass compared with Kentucky bluegrass and tall fescue. Crop Sci. 2007, 47, 2152–2161. [Google Scholar] [CrossRef]
  50. Wherley, B. Turfgrass growth, quality, and reflective heat load in response to deficit irrigation practices. In Evapotranspiration; Labedzki, L., Ed.; InTech: Rijeka, Croatia, 2011; pp. 419–430. [Google Scholar]
  51. Kneebone, W.; Kopec, D.; Mancino, C. Water requirements and irrigation. Turfgrass 1992, 32, 441–472. [Google Scholar] [CrossRef]
  52. Emekli, Y.; Baştuğ, R. Determination of Bermudagrass Evapotranspiration and Validation of Some Reference Evapotranspiration Equations under Open Field Conditions in Antalya. Akdeniz Univ. J. Fac. Agric. 2007, 20, 45–57. [Google Scholar]
Figure 1. The sub-surface drip (a) and pop-up (b) irrigation systems.
Figure 1. The sub-surface drip (a) and pop-up (b) irrigation systems.
Sustainability 15 15053 g001
Figure 2. Location of the Research Area.
Figure 2. Location of the Research Area.
Sustainability 15 15053 g002
Figure 3. Experimental area.
Figure 3. Experimental area.
Sustainability 15 15053 g003
Figure 4. Experimental design.
Figure 4. Experimental design.
Sustainability 15 15053 g004
Figure 5. Change in monthly irrigation water quantities.
Figure 5. Change in monthly irrigation water quantities.
Sustainability 15 15053 g005
Figure 6. Plant water consumptions.
Figure 6. Plant water consumptions.
Sustainability 15 15053 g006
Figure 7. Germination and emergence.
Figure 7. Germination and emergence.
Sustainability 15 15053 g007
Figure 8. Total mowing weights.
Figure 8. Total mowing weights.
Sustainability 15 15053 g008
Figure 9. Root lengths of experimental treatments.
Figure 9. Root lengths of experimental treatments.
Sustainability 15 15053 g009
Figure 10. Visual appearance of experimental plots.
Figure 10. Visual appearance of experimental plots.
Sustainability 15 15053 g010
Table 1. Experimental treatments.
Table 1. Experimental treatments.
TreatmentsDescription
S1100% Sub-surface drip irrigation with 0.40 m lateral spacing and 0.10 m lateral depth
S2100% Sub-surface drip irrigation with 0.40 m lateral spacing and 0.15 m lateral depth
S3100% Sub-surface drip irrigation with 0.60 m lateral spacing and 0.10 m lateral depth
S4100% Sub-surface drip irrigation with 0.60 m lateral spacing and 0.15 m lateral depth
S5100% Sub-surface drip irrigation with 0.80 m lateral spacing and 0.10 m lateral depth
S6100% Sub-surface drip irrigation with 0.80 m lateral spacing and 0.15 m lateral depth
S780% Sub-surface drip irrigation with 0.40 m lateral spacing and 0.10 m lateral depth
S880% Sub-surface drip irrigation with 0.40 m lateral spacing and 0.15 m lateral depth
S980% Sub-surface drip irrigation with 0.60 m lateral spacing and 0.10 m lateral depth
S1080% Sub-surface drip irrigation with 0.60 m lateral spacing and 0.15 m lateral depth
S1180% Sub-surface drip irrigation with 0.80 m lateral spacing and 0.10 m lateral depth
S1280% Sub-surface drip irrigation with 0.80 m lateral spacing and 0.15 m lateral depth
S1360% Sub-surface drip irrigation with 0.40 m lateral spacing and 0.10 m lateral depth
S1460% Sub-surface drip irrigation with 0.40 m lateral spacing and 0.15 m lateral depth
S1560% Sub-surface drip irrigation with 0.60 m lateral spacing and 0.10 m lateral depth
S1660% Sub-surface drip irrigation with 0.60 m lateral spacing and 0.15 m lateral depth
S1760% Sub-surface drip irrigation with 0.80 m lateral spacing and 0.10 m lateral depth
S1860% Sub-surface drip irrigation with 0.80 m lateral spacing and 0.15 m lateral depth
YS1100% Sprinkler Irrigation
YS280% Sprinkler Irrigation
YS360% Sprinkler Irrigation
Table 2. Soil physico-chemical properties.
Table 2. Soil physico-chemical properties.
DepthBulk
Density
(g cm−3)
Field
Capacity
(%)
Wilting
Point
(%)
Sand
(%)
Silt
(%)
Clay
(%)
TextureEC
(mmhos cm−1)
pHCaCO3
(%)
Organic
Matter
(%)
0–301.2927.1317.8236.441.122.5SCL0.5207.818.41.10
Table 3. Irrigation water quality parameters.
Table 3. Irrigation water quality parameters.
Chemical ParametersAnalysis Results
pH7.35
EC × 106 (µS cm−1)481
Dissolved Sodium Percentage 8.92
Sodium Absorption Ratio0.33
Hardness (FSD)26.8
Sulphur (S) (mg L−1)13.5
Boron (B) (mg L−1)0.03
Calcium (Ca) (mg L−1)62.3
Magnesium (Mg) (mg L−1)26.9
Sodium (Na) (mg L−1)12.3
Potassium (K) (mg L−1)4.07
Table 4. Irrigation water was applied to the experimental treatments (mm).
Table 4. Irrigation water was applied to the experimental treatments (mm).
2017
AprilMayJuneJulyAugustSeptemberOctoberTotal
S1–S635.60115.20150.40255.80216.20159.8033.60966.60
S7–S1228.4892.16120.32204.64172.96127.8426.88773.28
S13–S1821.3669.1290.24153.48129.7295.8820.16579.96
YS140.92132.41172.87294.02248.51183.6838.621111.03
YS232.74105.93138.30235.22230.62146.9430.90888.83
YS324.5579.45103.72176.41172.97110.2123.17666.62
2018
S1–S646.40126.20178.60250.80224.60150.4030.801007.80
S7–S1237.12104.16142.88200.64179.68120.3224.64806.24
S13–S1827.8478.12107.16150.48134.7690.2418.48604.68
YS153.33145.06205.29288.28258.16172.8735.401158.39
YS242.67116.05164.23230.62206.53138.3028.32926.71
YS332.0087.03123.17172.97154.90103.7221.24695.03
Table 5. Plant water consumptions (mm).
Table 5. Plant water consumptions (mm).
2017
AprilMayJuneJulyAugustSeptemberOctoberTotal
S1–S637.1141.4175.7257.1226.5160.836.31034.6
S7–S1231.7117.2145.8206.1182.9129.232.5845.3
S13–S1825.494.0116.1154.0140.497.829.9657.6
YS139.0149.4185.7271.8239.2170.838.41094.3
YS232.8123.5153.2216.4192.3135.733.9887.8
YS326.398.5121.6161.4147.4102.131.16688.5
2018
S1–S647.8146.3189.9251.80234.8151.433.51055.4
S7–S1240.3119.9154.4202.0189.6121.629.7857.8
S13–S1831.994.3119.0151.1145.592.128.1662.1
YS149.5152.6197.8261.9244.9157.234.81098.7
YS241.4125.3159.9210.0197.5126.330.9891.4
YS333.097.8123.1156.6151.6103.7229.3686.9
Table 6. Grass mowing height (cm) and weight (g) values for 2017.
Table 6. Grass mowing height (cm) and weight (g) values for 2017.
12345678910Total
S1Mowing date17.04.02.05.16.05.06.06.07.07.10.08.20.09.13.10.16.11.-9
Grass height13–1512–1412–1412–1411–1311–1311–1310–1210–12
Mowing weight3883012802982792862982782692674
S2Mowing date17.04.02.05.16.05.06.06.07.07.10.08.20.09.13.10.16.11.-9
Grass height13–1512–1412–1412–1411–1311–1311–1310–1210–12
Mowing weight3872962692802602642772612652559
S3Mowing date17.04.02.05.16.05.06.06.07.07.10.08.20.09.13.10.16.11.-9
Grass height13–1511–1312–1412–1411–1311–1311–1310–1210–12
Mowing weight3852802502582402432522402582407
S4Mowing date17.04.02.05.16.05.06.06.07.07.10.08.20.09.13.10.16.11.-9
Grass height13–1511–1312–1412–1411–1311–1311–1310–1210–12
Mowing weight3842722412552242252362302522309
S5Mowing date17.04.02.05.16.05.06.06.07.07.10.08.20.09.13.10.16.11.-9
Grass height13–1511–1312–1411–1310–1210–1211–1311–1310–12
Mowing weight3832582362402212172322222452254
S6Mowing date17.04.02.05.16.05.06.06.07.07.10.08.20.09.13.10.16.11.-9
Grass height13–1511–1312–1411–13 10–1210–1211–1311–1310–12
Mowing weight3812462252292062002162042352142
S7Mowing date17.04.10.05.06.06.12.07.21.08.09.10.16.11.---7
Grass height13–1511–1312–1410–1210–1211–139–11
Mowing weight3702502322352212322401780
S8Mowing date17.04.10.05.06.06.12.07.21.08.09.10.16.11.---7
Grass height13–1511–1312–1410–1210–1211–139–11
Mowing weight3722422212212062212341717
S9Mowing date17.04.15.05.16.06.02.08.09.10.16.11.----6
Grass height13–1511–1312–1410–1211–139–11
Mowing weight3722362212192252271500
S10Mowing date17.04.15.05.16.06.02.08.09.10.16.11.----6
Grass height13–1511–1312–1410–1211–139–11
Mowing weight3662272102102152201448
S11Mowing date17.04.17.05.21.06.11.08.11.10.16.11.----6
Grass height13–1510–1212–1410–1211–139–11
Mowing weight3592052012002032141382
S12Mowing date17.04.17.05.21.06.11.08.11.10.16.11.----6
Grass height13–1510–1212–1410–1210–129–11
Mowing weight3551981941911922091339
S13Mowing date17.04.18.05.27.06.03.10.16.11.-----5
Grass height13–1510–1212–1411–139–11
Mowing weight3571951922072151166
S14Mowing date17.04.18.05.27.06.03.10.16.11.-----5
Grass height13–1510–1212–1411–139–11
Mowing weight3591851811972081130
S15Mowing date17.04.18.05.03.07.06.10.16.11.-----5
Grass height13–1510–1212–1410–129–11
Mowing weight3521741751832021086
S16Mowing date17.04.18.05.03.07.06.10.16.11.-----5
Grass height13–1510–1212–1410–129–11
Mowing weight3511701701761971064
S17Mowing date17.04.26.05.24.07.10.10.16.11.-----5
Grass height13–1510–1212–1410–12 9–11
Mowing weight3551601731751901033
S18Mowing date17.04.26.05.24.07.10.10.16.11.---- 5
Grass height13–1510–1212–1410–129–11
Mowing weight327150162165180984
YS1Mowing date17.04.02.05.16.05.02.06.05.07.09.08.06.09.27.09.13.10.16.11.10
Grass height13–1512–1412–1412–1411–1311–1311–1311–1310–1210–12
Mowing weight3943122963062922932922822852793031
YS2Mowing date17.04.05.05.23.05.19.06.25.07.31.08.09.10.16.11.--8
Grass height13–1511–1312–1410–1210–1210–1211–139–11
Mowing weight3782652612602592402452522160
YS3Mowing date17.04.18.05.27.06.11.08.03.10.16.11.----6
Grass height13–1510–1212–1410–1210–129–11
Mowing weight3622021951901982111358
Table 7. Grass mowing height (cm) and weight (g) values for 2018.
Table 7. Grass mowing height (cm) and weight (g) values for 2018.
1234567891011Total
S1Mowing date16.04.30.04.18.05.04.06.02.07.03.08.03.09.27.09.15.10.19.11. 10
Grass height13–1511–1311–1311–1311–1311–1311–1310–1210–129–11
Mowing weight3802942963022942782912652592582917
S2Mowing date16.04.30.04.18.05.04.06.02.07.03.08.03.09.27.09.15.10.19.11. 10
Grass height13–1511–1311–1311–1311–1311–1311–1310–1210–129–11
Mowing weight3772862922902722592652462452522784
S3Mowing date16.04.30.04.18.05.04.06.02.07.03.08.03.09.27.09.15.10.19.11. 10
Grass height13–1511–1311–1311–1311–1311–1311–1310–1210–129–11
Mowing weight3732662802722492412462202232452615
S4Mowing date16.04.30.04.18.05.04.06.02.07.03.08.03.09.27.09.15.10.19.11. 10
Grass height13–1511–1311–1311–1311–1311–1311–1310–1210–129–11
Mowing weight3712572742622312242322112122422516
S5Mowing date16.04.30.04.18.05.04.06.02.07.03.08.03.09.27.09.15.10.19.11. 10
Grass height13–1511–1311–1310–1210–1210–1211–1310–1210–129–11
Mowing weight36924925725823021822222252212372486
S6Mowing date1.04.30.04.18.05.04.06.02.07.03.08.03.09.27.09.15.10.19.11. 10
Grass height13–1511–1311–1310–12 10–1210–1211–1310–1210–129–11
Mowing weight3652422482492122032092102092292376
S7Mowing date16.04.04.05.21.05.06.06.11.07.22.08.24.09.19.10.19.11.- 9
Grass height13–1510–1211–1310–1210–1210–1210–129–119–11
Mowing weight3602392402362072052061982232114
S8Mowing date16.04.04.05.21.05.06.06.11.07.22.08.24.09.19.10.19.11.- 9
Grass height13–1510–1211–1310–1210–1210–1210–129–119–11
Mowing weight3592322292252001971951852162038
S9Mowing date16.04.04.05.25.05.18.06.27.07.06.09.15.10.19.11.-- 8
Grass height13–1510–1211–1310–1210–129–1110–129–11
Mowing weight3552262322302222112092121897
S10Mowing date16.04.04.05.25.05.18.06.27.07.06.09.15.10.19.11.-- 8
Grass height13–1510–1211–1310–1210–129–1110–129–11
Mowing weight3522172252222142022012071840
S11Mowing date16.04.04.05.25.05.18.06.27.07.06.09.15.10.19.11.-- 8
Grass height13–1510–1211–1310–1210–129–1110–129–11
Mowing weight3471972182121951941992001762
S12Mowing date16.04.04.05.25.05.18.06.27.07.06.09.15.10.19.11.-- 8
Grass height13–1510–1211–1310–1210–129–1110–129–11
Mowing weight342190211205191881901941710
S13Mowing date16.04.18.05.15.06.23.07.04.09.12.10.19.11.--- 7
Grass height13–1510–1210–1210–1110–129–119–11
Mowing weight3401872021982012032001531
S14Mowing date16.04.18.05.15.06.23.07.04.09.12.10.19.11.--- 7
Grass height13–1510–1210–1210–1110–129–119–11
Mowing weight3381781971861921911931475
S15Mowing date16.04.18.05.15.06.23.07.04.09.12.10.19.11.--- 7
Grass height13–1510–1210–1210–1110–129–129–11
Mowing weight3301671981781851801861424
S16Mowing date16.04.18.05.15.06.23.07.04.09.12.10.19.11.--- 7
Grass height13–1510–1210–1210–1110–129–119–11
Mowing weight3281621881701801741781380
S17Mowing date16.04.31.05.29.06.20.08.08.10.19.11.---- 6
Grass height13–1510–1210–119–11 9–118–10
Mowing weight3201641811681701721175
S18Mowing date16.04.31.05.29.06.20.08.08.10.19.11.--- 6
Grass height13–1510–1210–119–119–118–10
Mowing weight3141551721551581601114
YS1Mowing date16.04.30.04.16.05.31.05.18.06.02.07.01.08.31.08.27.09.15.10.19.11.11
Grass height13–1511–1311–1311–1311–1311–1311–1311–1310–1210–129–11
Mowing weight3903163123183002962932952902812763367
YS2Mowing date16.04.30.04.18.05.06.06.04.07.07.08.06.09.28.09.15.10.19.11. 10
Grass height13–1511–1311–1310–1210–1210–1210–129–119–119–11
Mowing weight3662562682752532432452342212402601
YS3Mowing date16.04.18.05.15.06.23.07.04.09.12.10.19.11.--- 7
Grass height13–1510–1210–1210–1210–129–119–11
Mowing weight3451942042112101912081563
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Şahin, M. Potential Use of Subsurface Drip Irrigation Systems in Landscape Irrigation under Full and Limited Irrigation Conditions. Sustainability 2023, 15, 15053. https://doi.org/10.3390/su152015053

AMA Style

Şahin M. Potential Use of Subsurface Drip Irrigation Systems in Landscape Irrigation under Full and Limited Irrigation Conditions. Sustainability. 2023; 15(20):15053. https://doi.org/10.3390/su152015053

Chicago/Turabian Style

Şahin, Mehmet. 2023. "Potential Use of Subsurface Drip Irrigation Systems in Landscape Irrigation under Full and Limited Irrigation Conditions" Sustainability 15, no. 20: 15053. https://doi.org/10.3390/su152015053

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop