Beginning of implementation of Nature-Based Solutions (NbS) in Serbia: Case study of the first implemented rain gardens within suburban community Kać

doi:10.21203/rs.3.rs-2866498/v1

Download PDF

Research Article

Beginning of implementation of Nature-Based Solutions (NbS) in Serbia: Case study of the first implemented rain gardens within suburban community Kać

https://doi.org/10.21203/rs.3.rs-2866498/v1

This work is licensed under a CC BY 4.0 License

Journal Publication

published 29 Aug, 2023

Read the published version in Environmental Processes →

You are reading this latest preprint version

In recent years, the concept of Nature-based Solutions (NbS) is being accepted as an integrated approach that provides multiple ecosystem services. Serbia is among many European countries with a growing interest for the implementation of the NbS. This paper presents the results of assessment of two rain gardens (RGs) taken as case studies, implemented as some of the first examples of NbS. The research methodology is based on evaluation of the hydrologic effectiveness through continuous visual inspection during the period after RGs construction in the first year, second and third year after RGs establishment. Visual inspection involved observations of the basic functions of RGs i.e. flow reduction during storm events, presence of standing water or overflows, time of infiltration, vegetation health and establishment. Mentioned items were monitored in order to understand the performances and test the functionality of RGs due to their further implementation. Findings based on visual assessment showed that: a) both RGs infiltrate runoff during rain and snow events with no presence of standing water after 24 hours and b) rain gardens can reduce peak flows and total flow volume in a short period of time for rainfall depths that are connected with different return periods and flood frequency. The RGs also showed excellent plant growth rate and rapid plant establishment within environmental conditions in the RGs. This study highlights overall good adaptation of RGs under local soil and typical continental climate and contributes to limited research about performances of RGs as NbS in Serbian practice.

Nature-based Solutions (NbS)

Rain gardens (RGs)

Serbia

visual inspection

Nature-based Solutions (NbS) are defined as actions to preserve, sustainably manage and restore natural or modified ecosystems, while simultaneously providing human well-being and biodiversity benefits (Cohen-Shacham et al. 2016). The role of NbS is to help with protection from climate change impacts while slowing further warming (Seddon et al. 2020). Over the past years, there is a growing interest for the implementation of NbS in many European cities towards both climate mitigation and adaptation (Faivre et al. 2017; Maes and Jacobs 2017; Frantzeskaki 2019; Croeser et al. 2021). One of the NbS that is being implemented widely are rain gardens (RGs), also called bioretention systems, biofilters etc. that can be described as a small-scale NbS that are specially designed to collect, absorb and filter stormwater runoff from impervious areas, both in private gardens as well as in the urban context (Dunnett and Clayden 2007; Davis 2009; Steiner and Domm 2012; Woelfle-Erskine and Uncapher 2012; Church 2015). In relation to adaptation and resilience to ongoing climate change problems such as floods caused by heavy rains, degradation of urban streams as well as water pollution by hazardous substances, the use of RGs is connected with the principle of mitigation of the urban hydrological cycle in cities with biological treatment and protection of water quality (Davis 2009; Li et al. 2009; Johnson et al. 2020).

In Serbia, the NbS concept is still in the initial process of implementation. RGs as part of the NbS have been identified and proposed as a promising NbS approach to enhance stormwater management and generally sustainable development in Serbia, in particular in the direction of overcoming the challenges in mitigation of existing problems with urban floods and pollution (Đurakovac et al. 2018; Greksa et al. 2022; Ljubojević et al. 2022), but limited research is available on RGs performances in practice. Unlike previous studies, this paper aims to give concrete examples of installed RGs. Herein, two residential RGs implemented within suburban community are presented from the visual, ecological and hydrological aspect. Therefore, the aim of this paper is to provide fundamental evidence of the performances and functioning of RGs that are demonstrated within this study along with challenges that follow developing RGs projects in Serbia, where these systems are not being implemented yet on a large scale.

This article is organized as follows: section 2 describes the applied research methodology, construction details and the physical parameters of two implemented RGs in Serbia taken as case studies. Results of visual evaluation and field assessments of hydrological performances of analysed RGs are presented trough section 3. Section 4 discusses the obtained results while section 5 gives a summary and conclusion of this paper.

2.1. Assessment of RGs performances

For determining the performances of RGs in practice, four levels of assessment have been presented (Gulliver and Anderson 2008; Asleson et al. 2009 and Welker et al. 2013). Assessment with regard to NbS practices like RGs is the process for determining whether a RGs are effective at meeting one or all of its design objectives. Assessment may include visual inspection and testing or monitoring (Gulliver and Anderson 2008). Visual inspection is the 1st level of assessment and it involves evaluating three main components of RGs: (1) examination of the rain garden for obvious limitation in hydraulic functioning, (2) vegetation and (3) the inspection of the soil properties (Asleson et al. 2009; Welker et al. 2013). For the purpose of conducting visual inspection, two implemented RGs (RG₁ and RG₂) were constructed and taken as case studies. Evaluation period lasted continuously during 18 months for RG₁, that is 12 months for RG₂. RG₁ was installed in October, 2019 year while RG₂ was constructed in October 2020 year. Visual inspection and evaluation were done by applying an inspection checklist with the given visual inspection criteria based with consideration to primary goals and functions of RGs (Asleson et al. 2009; Welker et al. 2013). Visual inspection was done after rainfall or snowmelt, continuously for all rain events during winter, spring, summer and autumn months.

Hydrologic performances of RGs as the first component of visual inspection were assessed based on visual indications of drainage problems or impediments to infiltration, such as standing water present for more than 48 h after a rainfall event, sediment accumulation, erosion, analysis of soil moisture, presence of hydric soils, presence of emergent (wetland) vegetation or failing vegetation, while assessment of vegetation is done according to the age of the rain garden, time of the growing season, by examining and recording the color, size, and quality of the leaves, stem and flowers and the presence of invasive plant species (Asleson et al. 2009; Erickson et al. 2013; Welker et al. 2013). Plant establishment is determined by measuring the height of plants and overall vitality, while the percentage cover of plant was rated on a scale from 0 to 5, in relation to the space each plant had been given and thus varied with the planting distance as presented by Laukli et al. (2022). The inspection of the soil properties included analysis of soil texture, soil acidic (pH), soil color, hydric state and soil moisture (Asleson et al. 2009; Welker et al. 2013). Soil moisture was measured in the top 10–30 cm of RGs media 24 h and 48 h after rain, during periods without rain and during winter months. The measurement is done with a portable soil moisture meter that categorizes the intensity of moisture in the zone of the root system and humidity of soil as dry, medium and wet.

Methods of data collection and evaluation of RGs performances during visual inspection are presented in Table 1.

Table 1

Methods for data collection and evaluation of RGs performances during visual inspection
Component of visual inspection: Hydrological performances of RGs and the inspection of the soil properties
Factor of monitoring/indicators^a	Criteria for evaluation	The importance of inspecting	Methods of data collection and evaluation
Infiltration	Infiltration time (h)	Investigation of the ability of RGs to hold water long enough to hydrate the plants, but infiltrate the soil quickly enough	Visually determined; measured with the respect to the time needed for water in the ponded area to infiltrate after the precipitating event was ended (Erickson et al. 2013)
Prolonged saturation – ponded water	Ponded water present for more than 24–48 h after a rainfall event	Prolonged water retention can lead to rotting of plants and erosion, and therefore to poor hydrological and aesthetic performance of the RGs. Standing water shows that stormwater runoff does not infiltrate within the design drainage time.	Visually determined, measuring time of water “leaving” the ponding zone, measuring the depth of water a rain event or until the water is gone (Erickson et al. 2013; Welker et al. 2013)
Clogged gutters; presence of sediments or debris in inflow or the RGs’s bottom area	Accumulated sediments, debris or vegetation in gutters or in RGs area	Accumulated sediments, debris, vegetation can be a main limiting factor in a long-term operation of RGs, reduce infiltration rates and limit the treatment capacity of the RG or limit the stormwater runoff can enter in RG	Downspouts structures were regularly checked and cleaned of debris and vegetation leaves from surrounding trees in order to maintain good infiltration conditions of RGs Asleson et al. (2009)
Overflows	The runoff that bypasses the RGs	Overflows can indicate that the part of the runoff is not treated or infiltrated with RGs	Visually determined (Atchison et al. 2006)
Visible erosion or mulch material spread	Erosion, floating mulch over the surface of RGs	Indicate that flow velocities are too large or that stormwater runoff is entering or exiting the practice by means other than those intended by design	Visually determined Erickson et al. (2013)
Soil compaction	Crusting over surface soil	Can limiting root growth, limit infiltration	Visually and with soil sampling determined Erickson et al. (2013)

Table 1

Continued
Water color in RGs	The presence of murky or cloudy water in RGs	Runoff can contain a large suspended solids concentration	Erickson et al. (2013)
Soil color	The presence of soils that are gray in color or contain mottles (i.e. small areas of gray, red, yellow, brown	Soil color can be indicators of hydric soils	Visually determined and by soil sampling during inspection Asleson et al. (2009)
Soil moisture	Information on the infiltration rate as the moisture front moves through the soil	Helps to determine the capacity of soil pores to collect water	Manual soil moisture meter (Soil Ph Meter Ms02 3-in-1) Welker et al. (2013)
Component of visual inspection: Vegetation and ecological performances of RGs
Evaluation of plant diversity and coverage	Vegetative cover (%)	Indicates plant establishment under RGs conditions	Methods of Measurement: coverage evaluation scales from 0–5 (Laukli et al. 2022) 0 – no coverage/dead plants, 1 – low coverage, 2 – some coverage, 3 – medium coverage, 4 – good coverage, and 5 – very good coverage
Health of the plants	Color, quality, vitality of leaves, flowers, stems	Plants help to stabilize the soil in the RGs and increase evapotranspiration, thus reducing peak runoff and filtration of pollutants; provide aesthetic value, provides habitat for insects etc.	Visually determined; Asleson et al. (2009)
Plant height	Plant increasement rate, increasement of plant biomass	Indicates plant establishment under RGs conditions	Measured from the bottom to the top of the plant after construction and at the end of the inspection; Shaw and Schmidt (2003); Welker et al. (2013).
Weeds	Presence of invasive species in RGs	Weeds can significantly reduce water and nutrients for RGs plants	Visually determined; Asleson et al. (2009); Welker et al. (2013)

Table 1 Continued

Presence of wetland plant species		Indicates prolonged periods of saturation in RGs	Visually determined; Asleson et al. (2009)
Biological activity	Insect and animal utilization	Insect and animal utilization by insects, frogs, butterflies, bees, birds and mammals can provide insight into the established habitat value of RGs	Visually determined; Welker et al. (2013)
Aesthetic performances of RGs
Aesthetic considerations/biodiversity	Context, color, geometry/ shape, texture, variety, patterns and senses, fragrance	Planting a diversity of plant species combats to different climatic conditions, increases biodiversity and provides aesthetic value of RGs	Visually determined; Aesthetic Scoring Asleson et al. (2009)
^aAll indicators of RGs performances are chosen according to previous similar studies and recommendations for visual inspection analysis (Asleson et al. 2009; Erickson et al. 2013; Welker et al. 2013)

2.2. Locations of RGs and current environmental conditions

Both RGs taken as case studies are implemented on private residential properties to collect, retain and infiltrate runoff from the roof of buildings in a suburban community, Kać (45° 17' 59.53" latitude, 19° 56' 32.53" longitude) (Fig. 1). Kać represents one of the settlements of the municipality of Novi Sad, Serbia, covering the area of 74.87 km² with the current population of 11.612. Gardens are implemented on an area within a moderate-continental climate, the main characteristics of which are large temperature differences throughout the year (cold winters and hot summers) and sudden transitions between the colder and warmer half of the year. This means rainy springs, hot and dry summers, dryer autumns than spring and cold winters with little snow. According to Republic Hydrometeorological Institute of Serbia - RHMZS (hidmet.gov.rs). The coldest month is January with an average temperature of -1°C and the warmest is July with an average temperature of 21°C. Temperature extremes range from − 30.70°C to + 41.50°C. Frosty days appear in the period from October to May, while average evapotranspiration is significantly higher in May and June in compared to other months. The average annual amount of precipitation in the city of Novi Sad and its settlements is 605 mm, namely 132.6 mm in winter, 138.9 mm in spring, 205.5 mm in summer and 128 mm in autumn, but there is an increase in maximum daily and average annual precipitation in the past few years (hidmet.gov.rs). Short-term rains of high intensity are becoming more frequent, influencing that the total annual rain intensity has reached its maximum of over 1000 mm of rain per year and also contributing to the occurring of frequent flooding and pollution problems especially in the urban parts of the Novi Sad city (Greksa et al. 2022).

According to the existing pedological map of Serbia, native soil pedological substrate in the largest central part of Kać is characterized by chernozem soils. Chernozem is a soil rich in organic matter known for its high agronomical potential (Vysloužilová et al. 2016). It belongs to the class of humus-accumulative soils. It is characterized by a good crumbly structure, stable aggregates and good water permeability. In terms of chemical properties, it has a neutral to weakly alkaline chemical reaction (Mačkić et al. 2014).

2.3. Physical components of installed RGs

The design and implementation procedure for RGs that includes sizing, soil medium depth, depth of the ponding zone and recommended planting soil mixture and vegetation have been adapted from current national and international RGs guidelines and existing research statements (United States Environmental Protection Agency - US EPA 1999; Prince George’s County 2009; Dunnett and Clayden 2007; Carpenter and Hallam 2008; Roy-Poirier 2010; Woelfle-Erskine and Uncapher 2012; City of Portland 2016). This guidelines differ in the recommendations for the appropriate design and implementation of RGs, but the importance of site analysis prior to the design and installation of an RG is however, highlighted. The most important part of the prior analysis was soil infiltration capacity testing that was done in order to investigate the possibility of installing RGs on existing native soils. The testing involved digging two or more holes at different locations for planned RGs locations and filling them several times with water and then measuring average infiltration time (mm/h) (Erickson et al. 2013). The soil samples texture was determined using the USDA textural triangle, based on percent of sand, soil, and silt (Soil Survey Division Staff 1993) (Table 2, Table 3).

Table 2

Evaluation of current environmental conditions of RGs and analysis conducted pre and post RGs construction
Site analysis	Methodology	Reference
Amount of sun and shade Topography Surrounding vegetation	Determination of sunlight duration - direct sunlight related to plant needs. Full sun-6 hours per day during the plant's growing season; Partial lighting refers to 3–6 hours of direct sunlight; shade means less than 3 hours of direct sunlight Observation of slopes Determination of existing vegetation (plant count)	Shaw and Smith (2003) Prince George’s County (2009)
Infiltration rate of soil (Ksat)	Determined on in-situ percolation tests of the native soil; Ksat based on the U.S. Department of Agriculture (USDA) soil textural classes	Rawls et al. (1998) Erickson et al. (2013)
Soil type and texture	Determined using the USDA textural triangle, based on percent of sand, soil and silt	Soil Survey Division Staff. (1993)
Precipitation (rain and snow)	Gathered from the annual meteorological data of the Republic Hydrometeorological Institute of Serbia - RHMZS Observed from rain gauge installed in RG	(hidmet.gov.rs)
Soil acidity (pH)	Determined with soil moisture meter	Soil Ph Meter Ms02 3-in-1

Table 3

Properties of soil of RGs with the measured infiltration rates
Soil characteristics	RG₁	RG₂
Soil type	Loamy sand	Loamy sand
Hydrologic soil group^a	A	A
Ksat (cm/hr)^b	41.4	41.4
Soil pH	7.91	8.04
The measured rate of infiltration (mm/hr) after 1h^c	60	56
The measured rate of infiltration (mm/hr) after 2h	37	30
The measured rate of infiltration (mm/hr) after 24 h	33	28
Average measured infiltration rate (mm/hr)	44	38

(a)- Soil Survey Division Staff, 1999; (b)-Saturated Hydraulic Conductivity Based on USDA Soil Texture Class (Rawls et al. 1998); (c)- Measured during dry moisture conditions (no precipitation in the previous 5 days).

RG₁ was constructed with an area of 9 m² and a total depth of 60 cm, while RG₂ is characterized by an area of 10 m² and total depth of 40 cm. The depth of ponding zone was 20 cm for RG₁ and 15 cm for RG₂ (Fig. 2, Table 4). Gardens are constructed as infiltration types of garden, without an underdrain. The sizing ratio for gardens is taken as 10% of the treated impervious area (for RG₁) and 14% (for RG₂) (Atchison et al. 2006; Dunnett and Clayden 2007; Woelfle-Erskine and Uncapher 2012). Both RGs are designed in organic, curvy form. Planting soil mix for RGs included a mixture of 40% sand and 60% compost as recommended by Carpenter and Hallam (2008) for gardens whose goal is to promote infiltration. This planting mix was added after digging the soil intended for locating RGs. After RGs were installed, a 2–3 cm layer of mulch was added and large rocks were placed near the entrance point in order to break up the flow and slow the influent runoff.

Plants for RGs are chosen according to the recommended plant list considered to be tolerant to the different environmental conditions in RGs like oscillations of flooding and drought periods (Prince George’s County 2009; Dunnett and Clayden 2007; Uncapher and Woelfle-Erskine 2012; Hunt et al. 2015) and availability of this plants in local nursery near Kać (Fig. 3). The most common vegetation types that are recommended for planting are primarily perennials because perennial plantings require less maintenance than the annuals (Dunnett and Clayden 2007). A total of three different species was planted in RG₁ and seven in RG₂, with approximately 0.4-m to 0.8 m spacing between plants.

Table 4

Physical parameters of RGs (RG₁ and RG₂) and characteristics of soil media and vegetation
RG	Time of construction		Site conditions	Garden size (m²)	Contributing runoff area (roof) m²	Rain garden depth/ponding zone depth and total depth (cm)	Soil texture of native soil^a	RGs soil media/depth (%/cm)	RGs plants (species, number of used plants)^c	Planting zone (part of rain garden)
RG₁		Constructed in October 2019 year	-Full time sun (6 hours direct light) - Partly windy location -Private residences, multihousing	9	Roof (85.43)	60/20	Loamy sand (74.07% of sand, 18.5% silt, 7.40% of clay)	40% of sand 40% of compost^b: defined by total organic matter (52.4%); org N (1.56%); org. C (24.4%); 20% of topsoil	Juncus patens (7) Carex ice dance (3) Festuca glauca (5)	Middle RGs parts and near the gutter Outer - edge of garden Middle and edge of garden
RG₂		Constructed in October 2020 year	- Full time sun (6 hours direct light) - Partly windy location -Private residential single house	10	Roof (72)	40/15	Loamy sand (85.65% of sand, 9.5% silt, 4.85% of clay)	20% of sand 60% of compost^b: -defined by total organic matter (52.4%); org N (1.56%); org. C (24.4%); 20% topsoil	Juncus patens (4) Imperata cylindrica (2) Festuca glauca (5) Iris pseudocorus (4) Equisetum scirpoides (6) Gaillardia grandiflora (2) Glyceria maxima variegata (1)	Middle RGs parts and near the gutter Outer - edge of garden Middle RGs parts Middle RGs parts Middle RGs parts Outer - edge of garden Outer - edge of garden

(a)-Soil Survey Division Staff (1993); (b)-provided by the local compost supplier; (c)- procured from local nursery

3.1. Precipitation data and calculated volume of runoff managed by RGs

After the construction of RG₁ during the October 2019 year, the first recorded rain event was registrated after one week. This rain event lasted 2 hours and the total depth of rain was 7.5 mm. Estimated runoff volume for this rain event was 0.577 m³. This was also a flow test of RG₁ performance. The runoff from the gutter was flushing more in one direction so the largest amount of water was at the entrance of the garden and also, a little soil around the garden has eroded. No prolonged water was recorded and rain garden drained within 15 minutes after the rain. In general, total rain and snow events managed by RG₁ for the monitoring period of 18 months were 256. During the first months of inspection of RG₂, the only issue after rain was mulch floating and leaving some soil bares in several places in the gardens between plants after receiving runoff, so additional mulch was added. Total rain and snow events managed by RG₂ for the monitoring period were 158.

During the evaluation, the largest amount of the precipitation into RGs came as rain. From total of annual rainfall and snow events, 49.02% were less than 5 mm, while 22.55% were higher than 5 mm, with the number of rain events ranging between 122 per 2020 year and 143 per 2021 year. Only 1.47% of total precipitation were higher than 40 mm. In 2020 year, monthly precipitation ranged from 11.1 mm to 161.9 mm. This year was followed by a few extremely high rain events of which the highest number of recorded monthly precipitations was in June, respectively 169.1 mm. Some of the highest 24-hour rainfalls in 2020 year were also registrated in this month. The depths of these rain events were: 18.8 mm, 24.8 mm, 37.4 mm, 35.5 mm, 37.7 mm, 41.5 and 56.8 mm. On the contrary, April and November were months with the smallest amount of precipitation. The total annual amount of precipitation in 2020 year was 837.6 mm. In 2021 year, the annual amount of precipitation was 834.3 mm, while the average precipitation per month ranged from 16.4 mm to 114.14 mm. The highest 24-hour rainfall event was recorded in July amounting 38.1 mm. On average, November and July were the months with highest monthly precipitation and with the most days with precipitation in 2021 year (114.4 mm and 114.6 mm). Some of these high rainfall depths are associated with three different return period, i.e. flood frequency for the area within RGs are installed: the intensity of rainfall for the 2-year return period is 40.33 mm, for the 10-year return period 69.80 mm, while the depth of rainfall for the 100-year storm is 106.7 mm (Prohaska et al. 2014). The amount of monthly runoff managed with RGs is estimated to range from 0.577 m³ to 12.448 m³ for RG₁ (Table 5, Fig. 4). On average, RG₁ received a total of 134.241 m³ of runoff volume during the inspection, while this amount for RG₂ is estimated to be 63.426 m³. The volume of runoff managed by RG₂ is estimated at 9.363 m³ the first months of installation and 54.063 m³ after the first year of establishment. The amount of monthly runoff managed by RG₂ ranged from 0. 920 m³ to 8.094 m³. Total runoff amount managed by both RGs is estimated at 197.667 m³.

Table 5

Precipitation events and runoff volumes managed by RGs during the evaluation period, with an average measured time of infiltration per precipitation events
Month/Year	Rainfall/ snow depth (mm)^a	Calculated runoff volume (m³) for RG₁^b	Calculated runoff volume (m³) for RG₂^b	% of infiltrated water/ runoff capture for RG₁ and RG₂	Average measured time of infiltration for RG₁ (min)^c	Average measured time of infiltration for RG₂ (min)
10/2019	7.5	0.577		100	15
11/2019	53.7	4.129		100	40
12/2019	61.1	4.6977		100	42
∑month 2019=	122.3	9		100	100
01/2020	95	7.304		100	90
02/2020	45.5	3.498		100	34
03/2020	84.8	6.520		100	75
04/2020	11.1	0.853		100	13
05/2020	47.3	3.637		100	40
06/2020	161.9	12. 448		100	115
07/2020	78.6	6.043		100	67
08/2020	137.5	10.572		100	136
09/2020	31.4	2.414		100	39
10/2020	93	7.150	6.026	100	84	78
11/2020	14.2	1.092	0.920	100	10	15
12/2020	37.3	2.8678	2.417	100	36	41
∑month 2020=	837.6	64.3988	9.363	100	739	134
01/2021	90.7	6.974	5.877	100	102	125
02/2021	63.9	4.913	4.141	100	45	51
03/2021	42.8	3.291	2.773	100	38	47
04/2021	45.4	3.491	2.942	100	39	48
05/2021	62.9	4.836	4.076	100	43	45
06/2021	23.9	1.838	1.549	100	17	29
07/2021	114.4	8.796	7.413	100	145	161
08/2021	46.4	3.568	3.007	100	35	44
09/202	16.4	1.261	1.063	100	12	19
10/2021	88	6.766	5.702	100	69	75
11/2021	114.6	8.811	7.426	100	140	156
12/2021	124.9	9.603	8.094	100	149	159
∑month 2021=	834.3	64.148	54.063	100	834	550
∑total=	1794.2	134. 241	63. 426	100	1673	684

(a)-gathered from the annual meteorological data of the Republic Hydrometeorological Institute of Serbia - RHMZS (hidmet.gov.rs); (b)-the total volume of runoff water was obtained by multiplying the rainfall height and the associated roof area; (c)-average values of infiltration time per single rain/snow event, measured by the respect to the time needed for water in the ponding zone of RGs to infiltrate after precipitation event was ended.

3.2. Performance indicators in correlation to basic functions of RGs - infiltration and time of ponding

In general, RGs drained very quickly after receiving runoff from roofs. Partially ponding occurred only during higher rainfall depths (> 50 mm), but however, RGs were never completely filled with standing water after rain or snow melt. In RG₂ time of ponding was noted to last longer than in RG₁, with the periodical appearance of several bare spots between plants in the center of the RG basin, but also, there was never standing water and infiltration occurred almost immediately after rain. Based on visual observation, average measured infiltration of runoff after the precipitation event ranged from minimum 10 min for the rainfall depths that amounted 5 mm to 15 mm for RG₁ and 15 min for RG₂, to a maximum of 149 min (RG₁) and 159 min (RG₂) after monthly rainfall depths that were higher than 100 mm (Table 5, Fig. 4). During winter months hydrological performances of RGs are associated with the function of storing and treating snow i.e. the runoff created after its melting. Observations for RG_S during monitoring suggest that RGs continued infiltration during winter and that there was no influence on the performances of the RGs. During winter months (January to March), it was noted that the surface soil layer was frozen combined with low temperatures along and occurrences of frost. In 2020 year, snow was registrated in January marked by 10 days with snow and in March with snow cover depth ranging from 3 mm to 21 mm. During 2021 year snow was also registrated in January which was also the month with the greatest total number of days with snow.

3.3. Vegetation health, coverage and presence of weeds

Both RGs indicated rapid plant development after construction. In the first months of RGs installation, the most intensive vegetation maintenance was required. The maintenance included regular watering during the first few weeks after planting of vegetation until they were established. Plants were also watered whenever the soil was dry. After 1-year of RGs establishment vegetation covered most of the RGs basin. Off all species planted in RG₁, Juncus plants have shown a great development continuing to grow and spread out forming bunches to 90–120 centimeters in height while three Carex plants were damaged and dried over six months of planting. The plants were removed and replanted with plants of equivalent size during the spring of the first year. Juncus plants were regularly pruned in order not to become overcrowded. Festuca plants also showed good adaptation under RGs conditions without signs of foliage or rot damage. Although, one Festuca plant in RG₂ has completely dried during the first year. This plant was planted near the Glyceria maxima plant which has grown very fast spreading 150 cm in diameter. This caused Festuca plant to grow under shade completely covered with the habitat of Glyceria plant. Other species planted in RG₂ have indicated good adjustment based on measurements of plant height, very rapid growth, number and size of leaves and overall vitality of the plants. During winter months, vegetation in RGs also indicated good adaptation with no signs of leaves or root damage under low temperatures and frost.

Equisetum scirpoides plant had the highest average relative growth along with Juncus patens and Glyceria maxima plant, that was also characterized by the highest relative perimeter growth and increase in total biomass (Fig. 5, Table 6). Compared with an initial planting scheme density, the coverage of RGs has increased from 8.62–212%. According to the plant coverage class, vegetation in RGs is estimated to belong to the classes 4 and 5 (good coverage and very good coverage), with the exception of three Carex plants in RG₁ that were previously replanted. In the first and the second year of establishment, an increase in invasive, weed species was observed in RG₁. The appearance of weeds was particularly pronounced during vegetative dormancy periods during spring. Common weeds found in RGs were Taraxum officinale, Trifolium repens, Prickly lettuce (Lactuca), Barnyard grass (Echinochloa) and Portulaca oleracea (Fig. 6). In order not to be invasive and not to destroy the aesthetic appeal, weeding was regularly accomplished by hand whenever they appeared. In regard to RG₁, RG₂ was less affected with weeds only during the spring and summer period. On the contrary, no presence of wetland plant species in RGs was noted.

Table 6

Relative growth of plants in both RGs, with respect to their measured height and diameter during inspection period
RG	Plant species (scientific name)	Initial height of plants after construction (cm)	Initial perimeter of plants after construction (cm)	Plant height during/after inspection period (cm)*	Plant perimeter during/after inspection period (cm)*	Total plant's height increasement rate (%)	Total plant's perimeter increasement rate (%)
RG₁	Juncus patens	43–55	45–52	90–106	130–140	92.73–109.30	169.23-188.89
	Carex ice dance	16–17	19–22	15–17	22–26	18.75–29.41	15.79–18.18
	Festuca glauca	16–18	45–58	25–30	58–63	56.25–93.33	8.62–28.89
RG₂	Juncus patens	43–55	45–52	64–80	50–80	45.45–48.84	11.11–53.85
	Imperata cylindrica	40–44	60–66	67–79	120	50	79.10–100
	Festuca glauca	15–17	45–52	28–30	58–67	76.47–86.67	28.85–28.89
	Iris pseudocorus	19–23	15–25	36–38	40–78	65.22–89.47	166.67–212
	Equisetum scirpoides	30–36	47	130–150	75	316.67-333.33	59.57
	Gaillardia grandiflora	13–15	24–28	14–29	51–55	7.69–93.33	96.43–112.50
	Glyceria maxima variegata	43–55	146	89–145	180	106.98-163.64	23.29
*For RG₁ this is the period after 2 years of vegetation establishment, while for RG₂ it refers to the period after 1 year of vegetation establishment

3.4. Inspection of soil

Soil moisture analysis was conducted in order to test whether the soil is retaining sufficient moisture and therefore, draining adequately (Table 7). As expected, the amount of water infiltrated during rain increased the current soil moisture. After the 24-hour when the rainfall was ended, the inspection of soil pointed out that soil in RGs did not dry out. The soil moisture level on the moisture meter was detected as wet, indicating that there was some reserve of moisture in the soil. In general, the high moisture level was in the middle RGs parts that are connected with the direct runoff inflow and in within the ponding area zone. In the root zone area, around plants, the ratio of soil moisture was also high. In winter months, the highest soil moisture was detected during snow cover over RGs and after the snow was melted, while in the periods when the soil was frozen the soil moisture was low to medium in the middle RGs parts and around plant roots. The soil moisture was detected as dry to medium only in the period of consecutive days without precipitation, that is during the summer months. The inspection of the soil also showed that there was no visual evidence of sediment accumulation or erosion along the side slopes of gardens or surface clogging. Soil samples taken during different seasons were analysed for compaction, and also to inspect the color of the soil. During observations, all soil samples were homogeneous with no presence of gray color that is indicating hydric soils. In winter months, the moisture measurement and soil sampling was more difficult to achieve, because of the occurrence of frost that influenced on the formation of a compacted surface of RGs the soil.

Table 7

Estimated levels of soil moisture at the depth of 0–30 cm
RG zone	Ratio of moist 24-h after rain	Ratio of moist 48-h after rain	Ratio of moist during periods without rain	Ratio of moist during winter months*
Ponding area zone	wet	wet	moist to wet	moist to wet
Middle RGs parts	wet	wet	moist to wet	moist to wet
Entrance of RG	wet	wet	moist to wet	moist to wet
In the root zone area	wet	wet	moist to wet	moist to wet
*Determined during days without frost

4.1. Results of hydrological performances of RGs

Results of overall visual inspection of RGs and their establishement are presented trough Figs. 7 and 8 and Table 8. Overall results indicated that both RGs infiltrate runoff during rain and snow events, with no presence of standing water after 24 hours respectively, that RGs can reduce peak flows and total flow volume in a short time period. Although, during higher rain events, water remained on the surface of RGs slightly longer, that is over 2–3 hours. As regards, both RGs found to detain 100% of the rainfall connected with different 24 - hour storm events. Due to very short ponding time in both RGs and rapid infiltration after receiving runoff, soil texture has shown to correlate with high infiltration rates. Both RGs are defined by the native soil texture of loamy sand with high saturated hydraulic conductivity (Ksat) values and high percentage of sand. Measured time of infiltration prior to construction of RGs ranged from 28–60 mm/hr with an average infiltration rate of 44 mm/hr for RG₁ and 38 mm/hr for RG₂. This value is within the recommended optimal Ksat of soil for RGs, that is from 36–180 mm/h (Melbourne Water, 2005). In comparison to the initial infiltration rate, RGs maintained their average infiltration values. On the other hand, analysis of soil moisture levels has shown that the soil in RGs retains moisture for long which is, from the aspect of vegetation growth and support very preferable factor.

Studies have shown that the use of compost increases the porosity of the soil, affects the rate of infiltration and increases water retention capacity in the soil (Zemánek 2011). Organic matter is also an important source of carbon for microorganisms (Prince George’s County 2009). Ratio of compost in soil mixes in RGs was higher in RG₂, that is 20% higher for RG₂ relative to RG₁. Although, compost is primarily used to improve soil properties and not as a fertilizer, higher percentage of compost may have contributed to stimulate vegetative growth in RGs and overall long water holding capacity of soil. Sand as a medium added to the soil improves hydraulic conductivity of RGs (Prince George’s County 2009). The native soil texture of RGs was already rich with sand, but it can be assumed that the addition of sand in soil mixtures has increased the infiltration capacity of RGs. The analysis of pH shows that the pH values of soil are in the range of neutral (for RG₁) to low acid (RG₂), with no difference relative to soil before construction. Recommended pH for RGs is variable, but preferably neutral, with nominal pH 6.0 to pH 7.5 range (Prince George’s County 2007). Additionally, after the rain in both gardens the presence of earthworms was noted. Soil fauna has the potential to substantially alter plant growth, water infiltration rates and the retention and removal of pathogens, nutrients, heavy metals and other contaminants, enhance denitrification and nutrient uptake (Mehring and Levin 2015). Organisms in RGs can also capture and convert pollutants from stormwater runoff that may filter or infiltrate through the soil profile (Erickson et al. 2013).

4.2. Vegetation performances under RGs conditions

Visual inspections results about vegetation performances indicate an excellent plant growth rate and plant cover, rapid plant establishment and adaptation on environmental conditions in RGs. Besides a few plant damage and replacement, no modifications were made to the original planting scheme. In RG₁, Juncus plants are shown to be more resilient to environmental conditions in the RGs. Other studies reported similar findings about the ability of Juncus in adapting and tolerating different physical, climatic, and biological stresses and it is among plants that is highly recommended for RGs for its nutrient removal dynamics and year-round green aesthetics due to root architecture and physiology (Read et al. 2008; Muerdter et al. 2020). In RG₂, Equisetum plants had the greatest and fastest biomass increase. Marsh et al. (2000) reported high nutrient cycling in an Alaskan shrub wetland by these plants. Overall vitality and survivorship of plants was higher in RG₂ than in RG₁, where only one Festuca plant was detected as dry. Issue of dried Carex plants in RG₁ can be connected with extreme changes in weather conditions after the first months of planting. After frequent rain events and winter months, plants were exposed to drought stress. Although, Carex plants are among vegetation that can potentially survire in wet conditions and were planted in RG zone which is receiving more runoff (referred as emergent zone). Moreover, in RG₁ some Carex plants were planted further from the gutter in RG, the area that was least receiving runoff during some rain events. Plants selected for these areas may therefore need to be more drought resistant (Hunt et al., 2015). However, due to very rapid infiltration after rain events RGs in this study were never filled with water more than 5 hours, what may influence to the correct drawing of conclusions relating to the survival of plants in extended inudation conditions. On the other hand, plants near the entrance of runoff in RG₁ (Juncus) and RG₂ (Equisetum) that were more frequently inundated and impacted by higher flow velocities, have shown a high ability to develop resistance on environmental conditions in RGs.

Density of planted vegetation is singled out as an important factor for effective water treatment and reduced maintenance requirements (Payne et al. 2015). Rain gardens should be densely planted to control weeds and maximize water treatment (Hunt et al. 2015). This influence on dense planted vegetation can be noted on an example on RG₂. Relative to RG₁, RG₂ was less affected with weeds. As stated by Vasić et al. (2012) many perennial weed species in Serbia, have well-developed underground organs and are great problems not only in agriculture, but also in nursery production of forest planting materials during the entire spring and in early summer. Some species like Plantago major, Taraxacum officinale, Polygonum aviculare, Cynodon dactylon stand out pioneering character in Serbia and ability to adapt to diverse conditions (Gavrilović, 2016). Therefore, these weeds are a far greater challenge due to difficulties employing mechanical measures because perennials are often stimulated to grow and disperse even more intensively. Moreover, densely planted vegetation can increase the density of the roots, the infiltration capacity and porosity of the soil and also increase the degree of evapotranspiration (Hunt et al. 2015). Rain gardens planted with a variety of vegetation are more efficient than those planted with only one plant species (Read et al. 2008). In regards to RG₁, RG₂ is planted with more diverse plant species. The total number of different plant species in RG₁ is three, while in RG₂ this number is seven. Beside primary functions of infiltrating runoff, this makes RG₂ more pleasant in a visual context thanks to different form, color, bloom and texture of planted species.

During rainfall events, it was noted that the mulch has the tendency to float into a basin of RG₂. RGs can be generally designed with or without a layer of mulch cover. Nevertheless, preference is always given to mulch application because in addition to protecting the soil from drying and erosion, it also provides a medium for microorganisms that participate in the process of decomposition of organic material and adsorption of heavy metals (Hsieh and Davis 2005; Prince George’s County 2009). Furhermore, mulching of RGs is recommended as an important maintenance measure in order to maintain the infiltration rate of rain garden with age once every 2 to 3 years (Li et al. 2010).

Table 8

Results of overall visual inspection of RGs
Visual inspection results	RG₁			RG₂	Total number of observations		Time of inspection
Primary hydrological functions indicators	1-yr	2-yr	3-yr	1-yr	RG₁	RG₂	RG₁	RG₂
Water present for no more than 24–48 hours	No	No	No	No	256	158	24-48h after rain/snow	24-48h after rain/snow
Clogged gutters	No	No	No	No	256	158	24-48h after rain/snow	24-48h after rain/snow
Overflows	No	No	No	No	256	158	24-48h after rain/snow	24-48h after rain/snow
Visible erosion or mulch material spreads	After first rain event	No	No	After first rain event	256	158	Monthly/yearly	Monthly/yearly
Presence of sediments or debris in inflow or the RGs’s bottom area	In gutters during autumn	In gutters during autumn	In gutters during autumn	In gutters during autumn	256	158	Monthly/yearly	Monthly/yearly
Insect and animal utilization	Presence of earth worms and butterflies	Presence of earth worms and butterflies	Presence of earth worms and butterflies	Presence of earth worms butterflies	256	158	Monthly/yearly	Monthly/yearly
Soil and vegetation performance indicators	1-yr	2-yr	3-yr	1-yr	1-3yr	1-yr	1–3 yr	1-yr
Soil compaction	No	No	No	No	From Oct, 2019 year to Oct 2021 year	From Oct, 2020 year to Oct 2021 year	Monthly/yearly	Monthly/yearly
The presence of wetland plant species	No	No	No	No	-II-	-II-	Monthly/yearly	Monthly/yearly
Presence of invasive plants	Yes	Yes	Yes	Yes	-II-	-II-	Monthly/yearly	Monthly/yearly
Health of the plants	Very good	Excellent	Excellent	Excellent	-II-	-II-	Monthly/yearly	Monthly/yearly
Visible damage of plants	Three Carex plants	No	No	One Festuca plants	-II-	-II-	Monthly/yearly	Monthly/yearly
Plant diversity and coverage	50–60%	80–90%	90%	80–90%	-II-	-II-	Monthly/yearly	Monthly/yearly

4.3. The influence of age, the size and character of the catchment area of RGs on the results of hydrological performance

The ratio of the area (size) of RGs in relation to the total impermeable surface to be treated (Contributing Drainage Area-CDA) is much higher for the RG₁ than for the RG₂. On the contrary, the total size of RG₁ area is smaller than RG₂, but it is predicted to manage the higher amount of generated runoff compared to RG₂. According to Davis et al. (2009), RGs should be used as a source control for small drainage areas, maximum approximately 8,000 m². Larger CDA will require larger RGs for achieving goals like runoff reduction and increasing water quality. Therefore, the amount of runoff has a great influence on sizing RGs. In the case of RG₁, although it is designed with smaller area compared to RG₂, however, it is characterized by greater ponding depth, providing greater initial storage volume to capture stormwater runoff and therefore, increasing the percentage of captured runoff volume (Prince George’s County 2009). The medium depth also plays an important role in the effectiveness of the RGs. Thicker soil section can provide more opportunities for adsorption, filtration and contact with decomposing microorganisms by increases exfiltration i.e. infiltration to native soils below the excavated area of the rain garden itself and providing more detention capacity, affect plants’ growth or even survival (Ewing 2013). Based on this statement, RG₁ has a potential for managing and infiltrating higher volumes of runoff than RG₂. The main consideration in determining the size of RG, is achieving a specified design storm volume and treat the runoff from the "first flush", respectively 25 mm of rainfall (US EPA 1999). The results of this study show that both RGs have the capacity for infiltrating rainfall depths that are 25 mm and higher.

Although there is a limited literature on performance of mature RGs, some existing research results have shown that RGs maintain high hydrologic performance over the years (Spraakman et al. 2020). According to Malaviya et al. (2019) RGs have a predicted design life of about 25 years. Compared to RG₂, RG₁ is a three-year old established garden but comparing overall results in this study, it can be noted that RGs did not differ much in their primary functions and there was no great influence of RGs age on hydrological and ecological performances.

4.4. Future challenges for developing RGs on a larger scale in Serbia

There are many aspects to be considered before further implementation of RGs and other NbS in Serbia. Primarily, community acceptance of RGs in general as more desirable and ecological solution is essential for their wide range of applications and improving sustainability of cities. Rain gardens presented in this study are implemented on a suburban area and have been properly and regularly maintained by the homeowners. For more urban conditions in Serbia, performances of RGs and their maintenance may differ. However, even at the level of the individual, private yards, implementation of RGs can contribute to climate adaptation with NbS and provide multiple ecosystem services. In a denser urban areas, many limitations impact the challenge in implementing RGs like achieving harmonization of the existing and planned networks of installations while simultaneously satisfying all other functions such as traffic. Besides that, the primary consideration for implementing RGs at the locations along streets and roads are connected with finding the appropriate plant species subjected to combined stresses including periodic inundation, de-icing salts, road dust, splashes etc. (Laukli et al. 2022).

Climatic conditions in Kać and generally in Serbia are distinguished with the majority of annual precipitation and maximum measured daily and monthly precipitation to be in June and July, that is during the summer months, so future RGs need to be designed according to these events with special reference to prolonged drought periods, with a few months without rainfall which can have a negative impact on soil and plants. It is necessary to develop more RGs projects that will be sized and designed properly, in order to accommodate to a site specific characteristics in accordance with different urban and suburban conditions and also, to manage rainfall depths associated with different return period. Suburban areas of the city of Novi Sad also have implications for water quality, primarily in water pollution caused by runoff and due to the common sewage system. Therefore, NbS examples in this paper can contribute to the better understanding of likages between urban cities and associated suburban areas.

Based on the results of a comprehensive visual inspection presented in this study, it can be concluded that RGs are effective in managing runoff, functioning properly during rain and snow events and in supporting plant growth and establishment. Therefore, the concept of RGs as NbS can be applied under local soil conditions and typical continental climate. Both RGs provided 100% volume retention for different rain and snow events and there was no evidence of hydrologic failure. Confirmed by the observations, the infiltration rate was excellent, indicating that the RGs never have standing water for an extended time, respectively, they drain within a maximum of 3 hours. Assessments of vegetation provided lessons on which plants are able to survive the variable conditions in RGs planted within a continental climate which can be very significant when choosing plants for future RGs projects. As evidenced, proper plant selection and their proper arrangement are critical to achieving a balance between the facility function and plant health and can provide visual clues as to the functionality of RGs. Some plants like Carex have shown to have lower ability to develop resistance on environmental conditions in RGs conversely to other plants. Besides that, weed control is essential for maintaining high levels of plant performance and to prevent their invasion because of their fast spreading. In general, the successful functioning of RGs depends upon proper and regular maintenance. Considering overall RGs performances it can be concluded that RGs accomplished the "first flush" runoff management requirements, taking into account that RGs have managed different rainfall depth associated with different return periods ie. flood frequency.

The RGs presented in this study are among the first examples of RGs in Serbia, respectively, the starting point of the ongoing effort of changes in vision of the transition from the standard gray to sustainable drainage solutions. As regards, this article can help with support for further implementation and research analysis by demonstrating RGs effectiveness, benefits and potential limitations by taking into consideration local environmental conditions and the use of local soil and vegetation. Moreover, the results will make a significant contribution to the existing research on the topic of implementation and functioning of RGs. This paper was mainly focused on visual conclusions and experience about RGs performances. Visual inspection as a monitoring method can obtain quantitative information on the performance of RGs effectiveness, but however, additional further assessment via testing pollutant removal is planned in order to help to identify the performances of RGs from the aspect of improving stormwater quality.

Competing interests

The authors have no relevant financial or non-financial interests to disclose.

Authors' contributions

All authors contributed to the study conception and design.

Material preparation, data collection trough inspection, monitoring and analysis of rain gardens were performed by Amela Greksa. Hydrological data analyses was performed by Boško Blagojević, while ecological data analyses was performed by Jasna Grabić. The first draft of the manuscript was written by Amela Greksa and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Funding

The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.

Availability of data and materials

The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.

Asleson BC, Nestingen RS, Gulliver JS, Hozalski RM, Nieber JL (2009) Performance assessment of Rain gardens 1. JAWRA J Am Water Resour Association 45(4):1019–1031. https://doi.org/10.1111/j.1752-1688.2009.00344.x
Atchison D, Potter KW, Severson L (2006) Design guidelines for stormwater bioretention facilities. Water Resources Institute. https://publications.aqua.wisc.edu/product/design-guidelines-for-stormwater-bioretention-facilities/. Accessed 13 August 2021
Carpenter DD, Hallam L (2008) An investigation of rain garden planting mixture performance and the implications for design. Proceedings of the 2008 National LID Annual Conference. Seattle. WA. https://doi.org/10.1061/41009(333)2
Church SP (2015) Exploring Green Streets and RGs as instances of small scale nature and environmental learning tools. Landsc Urban Plann 134:229–240. https://doi.org/10.1016/j.landurbplan.2014.10.021
City of Portland, Portland CO (2016) Stormwater management manual. Portland: City of Portland Bureau of Environmental Services. https://www.portlandoregon.gov/bes/71127. Accessed 13 August 2021
Cohen-Shacham E, Walters G, Janzen C, Maginnis S (2016) Nature-based solutions to address global societal challenges. IUCN: Gland Switzerland 97:2016–2036. https://doi.org/10.2305/IUCN.CH.2016.13.en
Croeser T, Garrard G, Sharma R, Ossola A, Bekessy S (2021) Choosing the right nature-based solutions to meet diverse urban challenges. 127337. Urban Forestry & Urban Greeninghttps://doi.org/10.1016/j.ufug.2021.127337. 65
Davis AP, Hunt WF, Traver RG, Clar M (2009) Bioretention technology: Overview of current practice and future needs. J Environ Eng 135(3):109–117. https://doi.org/10.1061/(ASCE)0733-9372(2009)135:3(109)
Dunnett N, Clayden A (2007) Rain gardens: Managing water sustainably in the garden and designed landscape. Timber Press
Erickson AJ, Weiss T, Gulliver JS (2013) Optimizing stormwater treatment practices: A handbook of assessment and maintenance. Springer Science & Business Media
Ewing C (2013) Assessment of International Bioretention Soil Media: Guidelines and Experiences. University of Copenhagen: Copenhagen, Denmark
Faivre N, Fritz M, Freitas T, De Boissezon B, Vandewoestijne S (2017) Nature-Based Solutions in the EU: Innovating with nature to address social economic and environmental challenges. Environ Res 159:509–518. https://doi.org/10.1016/j.envres.2017.08.032
Frantzeskaki N (2019) Seven lessons for planning nature-based solutions in cities. Environ Sci Policy 93:101–111. https://doi.org/10.1016/j.envsci.2018.12.033
Gavrilović M (2016) Ruderal flora of Novi Sad as a potential natural resource of medicinal plants Ph.D. Thesis. University of Novi Sad. Serbia
Greksa A, Grabić J, Blagojević B (2022) Contribution of low impact development practices-bioretention systems towards urban flood resilience: case study of Novi Sad Serbia. Environmental Engineering Research 2022; 27(4): 210125. https://doi.org/10.4491/eer.2021.125
Gulliver JS, Anderson JL (eds) (2008) Assessment of stormwater best management practices. University of Minnesota. https://larrybakerlab.cfans.umn.edu/sites/larrybakerlab.cfans.umn.edu/files/files/stormwater-assessment-manal.pdf. Accessed 10 January 2023
Đurakovac A, Mihajlovic I, Dogo M, Sekulic M, Markovic M, Miloradov MV (2018) Bioretention systems as a part of advanced environmental treatment practice of wastewater in the city of Novi Sad. Fresenius Environ Bull 27(1):283–290
hidmet.gov.rs (2022) https://www.hidmet.gov.rs/. Accessed 10
Hsieh CH, Davis AP, Needelman BA (2007) Bioretention column studies of phosphorus removal from urban stormwater runoff. Water Environ Res 79(2):177–184. https://doi.org/10.2175/106143006X111745
Hunt WF, Lord B, Loh B, Sia A (2015) Plant selection for bioretention systems and stormwater treatment practices. Springer Nature, p 59
Johnson JP, Hunt WF (2020) Field assessment of the hydrologic mitigation performance of three aging bioretention cells. J Sustainable Water Built Environ 6(4):04020017. https://doi.org/10.1061/JSWBAY.0000925
Laukli K, Vinje H, Haraldsen TK, Vike E (2022) Plant selection for roadside RGs in cold climates using real-scale studies of thirty-one herbaceous perennials. Urban Forestry & Urban Greening. https://doi.org/10.1016/j.ufug.2022.127759. 127759
Li MH, Dvorak B, Sung CY (2010) Bioretention low impact development and stormwater management. Urban Ecosyst Ecol 55:413–430. https://doi.org/10.2134/agronmonogr55.c20
Li H, Sharkey LJ, Hunt WF, Davis AP (2009) Mitigation of impervious surface hydrology using bioretention in North Carolina and Maryland. J Hydrol Eng 14(4):407–415. https://doi.org/10.1061/(ASCE)1084-0699(2009)14:4(407)
Ljubojević M, Narandžić T, Ostojić J, Božanić Tanjga B, Grubač M, Kolarov R, Greksa A, Pušić M (2022) Rethinking Horticulture to Meet Sustainable Development Goals—The Case Study of Novi Sad Serbia. Horticulturae 8(12):1222. https://doi.org/10.3390/horticulturae8121222
Maes J, Jacobs S (2017) Nature-based solutions for Europe's sustainable development. Conserv Lett 10(1):121–124. https://doi.org/10.1111/conl.12216
Malaviya P, Sharma R, Sharma PK (2019) RGs as stormwater management tool. In Sustainable green technologies for environmental management Springer. Singapore pp 141–166. https://doi.org/10.1007/978-981-13-2772-8_7
Mačkić K, Pejić B, Nešić L, Vasin J, Mijić B (2014) Chemical properties of chernozem influenced by irrigation. Research journal of agricultural science. 46(2)
Marsh AS, Arnone IIIJA, Bormann BT, Gordon JC (2000) The role of Equisetum in nutrient cycling in an Alaskan shrub wetland. J Ecol 88(6):999–1011. https://doi.org/10.1046/j.1365-2745.2000.00520.x
Mehring AS, Levin LA (2015) Potential roles of soil fauna in improving the efficiency of RGs used as natural stormwater treatment systems. J Appl Ecol 52(6):1445–1454. https://doi.org/10.1111/1365-2664.12525
Melbourne Water (2005) WSUD engineering procedures: Stormwater. Csiro Publishing
Muerdter CP, Smith DJ, Davis AP (2020) Impact of vegetation selection on nitrogen and phosphorus processing in bioretention containers. Water Environ Res 92(2):236–244. https://doi.org/10.1002/wer.1195
Payne EGI, Hatt BE, Deletic A, Dobbie MF, McCarthy DT, Chandrasena GI (2015) Adoption guidelines for stormwater biofiltration systems—Summary report. Cooperative Research Centre for Water Sensitive Cities Melbourne. https://watersensitivecities.org.au/wp-content/uploads/2015/10/TMR_C1-1_AdoptionGuidelinesStormwaterBiofiltrationSystems_2.pdf. Accessed 16 June 2022
George’s County P (2009) M D Bioretention manual. Environmental Services Division Department of Environmental Resources The Prince George's County Maryland. https://portal.ct.gov/-/media/DEEP/p2/raingardens/BioretentionManual2009Versionpdf.pdf. Accessed 20 June 2022
Prohaska S, Bartoš Divac V, Koprivica A et al (2014) Intensities of heavy rains in Serbia. Institute of Water Management “Jaroslav Cerni”;, Belgrade
Rawls WJ, Gimenez D, Grossman R (1998) Use of soil texture bulk density and slope of the water retention curve to predict saturated hydraulic conductivity. Trans ASAE 41(4):983
Read J, Wevill T, Fletcher T, Deletic A (2008) Variation among plant species in pollutant removal from stormwater in biofiltration systems. Water Res 42:893–902. https://doi.org/10.1016/j.watres.2007.08.036
Roy-Poirier A, Champagne P, Filion Y (2010) Review of bioretention system research and design: past. present. and future. Journal of Environmental Engineering 136(9) pp 878–889. https://doi.org/10.1061/(ASCE)EE.1943-7870.0000227
Seddon N, Chausson A, Berry P, Girardin CA, Smith A, Turner B (2020) Understanding the value and limits of nature-based solutions to climate change and other global challenges. Philosophical Trans Royal Soc B 375(1794):20190120. https://doi.org/10.1098/rstb.2019.0120
Shaw D, Schmidt R (2003) Plants for Stormwater Design: Species Selection for the Upper Midwest. Minnesota Pollution Control Agency, Saint Paul, MN. https://www.pca.state.mn.us/sites/default/files/pfsd-section1.pdf. Accessed 25 June 2022
Soil Survey Division Staff (1993) Soil survey manual U.S. Dept. of Agriculture Handbook No. U.S. Govt. Printing Office. Washington. DC. https://www.rosemonteis.us/sites/default/files/references/usda-1993.pdf. Accessed 25 June 2022
Spraakman S, Van Seters T, Drake J, Passeport E (2020) How has it changed? A comparative field evaluation of bioretention infiltration and treatment performance post-construction and at maturity. Ecol Eng 158:106036. https://doi.org/10.1016/j.ecoleng.2020.106036
Steiner LM, Domm RW (2012) RGs: sustainable landscaping for a beautiful yard and a healthy world. Voyageur Press
United States Environmental Protection Agency (US EPA) (1999) Preliminary Data Summary of Urban Storm Water Best Management Practices (EPA-821-R-99-012). Office of Water Washington DC. https://www.epa.gov/sites/default/files/2015-11/documents/urban-stormwater-bmps_preliminary-study_1999.pdf. Accessed 20 June 2022
Vasić V, Konstantinović B, Orlović S (2012) Weeds in forestry and possibilities of their control. In Weed control. IntechOpen. 10.5772/34792
Vysloužilová B, Ertlen D, Schwartz D, Šefrna L (2016) Chernozem. From concept to classification: a review. AUC Geogr 51(1):85–95. https://doi.org/10.14712/23361980.2016.8
Welker AL, Mandarano L, Greising K, Mastrocola K (2013) Application of a monitoring plan for storm-water control measures in the Philadelphia region. J Environ Eng 139(8):1108–1118. https://doi.org/10.1061/(ASCE)EE.1943-7870.0000714
Woelfle-Erskine C, Uncapher A (2012) Creating Rain gardens. Timber Press
Zemánek P (2011) Evaluation of compost influence on soil water retention. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 59(3):227–232. https://doi.org/10.11118/actaun201159030227

No competing interests reported.

Download PDF

Journal Publication

published 29 Aug, 2023

Read the published version in Environmental Processes →

Editorial decision: Major revision
24 Jun, 2023
Reviews received at journal
11 Jun, 2023
Reviewers agreed at journal
08 May, 2023
Reviewers agreed at journal
03 May, 2023
Reviewers agreed at journal
02 May, 2023
Reviewers invited by journal
02 May, 2023
Editor assigned by journal
01 May, 2023
Submission checks completed at journal
01 May, 2023
First submitted to journal
26 Apr, 2023

You are reading this latest preprint version

Beginning of implementation of Nature-Based Solutions (NbS) in Serbia: Case study of the first implemented rain gardens within suburban community Kać

Status:

Journal Publication

Version 1

Abstract

Figures

1. Introduction

2. Materials and methods

2.1. Assessment of RGs performances

2.2. Locations of RGs and current environmental conditions

2.3. Physical components of installed RGs

3. Results

3.1. Precipitation data and calculated volume of runoff managed by RGs

3.2. Performance indicators in correlation to basic functions of RGs - infiltration and time of ponding

3.3. Vegetation health, coverage and presence of weeds

3.4. Inspection of soil

4. Discussion

4.1. Results of hydrological performances of RGs

4.2. Vegetation performances under RGs conditions

4.4. Future challenges for developing RGs on a larger scale in Serbia

5. Conclusion

Declarations

References

Additional Declarations

Status:

Journal Publication

Version 1