Urban Lawns Research Articles

Spatial Variability in the Speciation of Lead (Pb) and Other Metals Across Urban Lawns Is Linked to Post-Deposition Weathering Reactions

The historical use of lead (Pb) poses ongoing health risks via exposure to contaminated urban soils. However, there is limited information about heterogeneity in Pb speciation and distribution at the house lot scale. This study determined highly spatially resolved Pb and other metal speciation along horizontal transects and vertical soil cores from three homes in the Akron, Ohio (USA) municipal. Solid phase characterization was coupled with a sequential extraction protocol to determine operationally defined speciation (exchangeable (MEX), reducible (MRED), oxidizable (MOX), and residual (MRES)). Lead and Zn were strongly correlated across all fractions (R2 = 0.92). Total extractable Pb and Zn were found in low weight percent concentrations nearest to the homes, and speciation was dominated by MEX and MRED. High Pb in the MEX fraction was correlated with the presence of Pb-bearing paint chips in the soil. Lead in the MEX fraction in soils near the homes decreased with increasing time due to exterior renovations coupled with increases in Pb and Zn in the MRED fraction. These results suggest that homes are the dominant source of Pb and Zn due to the weathering of exterior surfaces and highlight the acute risk of exposure to more labile Pb immediately following exterior renovations and damage to home exteriors in areas of older housing stock.

Large eddy simulation of droplet dispersion and deposition over street canyons

Predicting droplet transport in the atmosphere is a major issue for a large number of dispersion problems such as spray cooling systems in streets, urban lawn sprinklers [Milesi et al., “Interferometric laser imaging for respiratory droplets sizing,” Environ. Manage. 36, 426–438 (2005)], and dispersion of virus such as COVID or from a terrorist attack [Balachandar et al., “Host-to-host airborne transmission as a multiphase flow problem for science-based social guidelines,” Int. J. Multiphase Flow 132, 103439 (2020)]. Here, we investigate the propagation of droplets issued from a source near the ground between square obstacles with different spacings. The aerodynamic field is determined by large eddy simulation coupled with an immersed boundary method for the obstacles. Droplets are tracked by a Lagrangian approach. An evaporation model is used to account for varying humidity conditions. Droplet concentration, mass flux, and deposition rates are obtained for different evaporation conditions and obstacle spacings. The results show high deposition rates on the internal wall of the first obstacle due to droplet advection by the reverse flow of the primary vortex. In addition to this, droplets may escape the canyon and propagate downstream as far as eight times the obstacle distance (8H). The concentration of air-borne droplets downstream the canyon is higher for smaller street canyon openings. When evaporation is accounted for, the ground-level droplet concentration may be reduced by up to 30% in the case of small canyon openings.

Evaluating the tradeoffs between water conservation, aesthetic value, evaporative cooling and CO2 emissions in St. augustinegrass and buffalograss

Urban lawns comprise a significant portion of urban greenery and provide several ecosystem services. Nevertheless, maintaining lawns comes with significant water costs in semi-arid inland southern California, as they require consistent irrigation to stay healthy and productive. The main objective of this study was to evaluate the effect of a wide range of irrigation rates and frequencies applied autonomously by a smart ET-based controller on the aesthetic value, cooling potential, and CO2 efflux of two warm-season turfgrass species. For three years, we studied the responses of Buffalograss and St. Augustinegrass to six irrigation rates and two irrigation frequencies in Riverside, California. Under historical average climate conditions, the minimum irrigation rate for Buffalograss was 93 % ETo, and for St. Augustinegrass, it was 74 % ETo. Under projected future climate conditions, the estimated minimum irrigation rate for Buffalograss did not change, but for St. Augustinegrass, it increased by 4 % and 7 % in 2100 under low emission (RCP 4.5) and high emission (RCP 8.5) scenarios, respectively. On average, canopy minus air temperature in Buffalograss was 6.2 ℃, and in St. Augustinegrass, it was 1.1 ℃. The average CO2 efflux in Buffalograss was 122.3 µg CO2-C m−2 s−1, and in St. Augustinegrass, it was 182.8 µg CO2-C m−2 s−1. Our results showed that turfgrass aesthetic values, cooling potential, and CO2 efflux diminished as the irrigation rate decreased, but at different rates for each turfgrass species.

Genetic lineages of <i>Parisotoma notabilis</i> sensu lato (Hexapoda, Collembola) and their use in biological monitoring

Widespread species of small soil arthropods are being traditionally used in the biological monitoring of the environment. A promising development in this direction could be the usage of genetic methods, namely the composition of genetic lineages in populations of polytypic species. These species include the widespread springtail, Parisotoma notabilis sensu lato, which is especially abundant in Europe. At present, six lineages of this complex are known, the genetic distances between which are sufficiently close to the species. Previously, we showed the differentiation of genetic lineages in an urbanization gradient (natural forest – forest park – urban lawn) using the Moscow region as an example. In this work, the divergence of genetic lineages in these habitats was confirmed for various natural zones. The least disturbed habitats are marked by lineages L2, L4-Hebert and L0, the most disturbed ones by L1. Monitoring changes in the soil layer of ecosystems is possible only in zones of sympatry of different P. notabilis genetic lineages, i.e. the areas where they co-occur. Such areas seem to include the entire European part of Russia.

From lawns to meadows: spiders (Arachnida: Araneae) as indicators to measure urban grassland restoration success

In the present study, we investigate how spiders can be used to assess the effectiveness of restoring mesic grasslands on former urban lawns. We compile and analyze a comprehensive dataset, including both past and current data, focusing on the Aachen region. By systematically examining this data, we identify various indicators using different analytical methods. This approach allows us to distinguish distinct species communities, making them useful as diagnostic tools at various stages of habitat development. Additionally, we identify further parameters that are essential for evaluating meadow restoration in urban settings. We highlight the crucial importance of understanding the local species repertoire, as this knowledge is vital for setting realistic benchmarks for restoration projects.

Carex parva and Carex scabrirostris adopt diverse response strategies to adapt to low-light conditions.

In recent years, the visible light intensity of lawns has significantly decreased due to obstructions caused by urban shading objects. Carex has a competitive advantage over other turfgrass in low-light conditions and extensive management. Therefore, exploring their survival strategy in low-light environments is of great significance. This study focuses on two species of Carex, Carex parva and Carex scabrirostris, and investigates their response to low-light conditions (150 μmol/m2/s) by simulating urban lawn conditions. Biomass allocation characteristics, leaf anatomical features, biochemical parameters, root morphology and photosynthetic parameters were measured. (a) Peroxidase activity, specific leaf area, and relative water content are key factors influencing the photosynthetic capacity of the two Carex species. (b) Under low-light conditions, photosynthetic parameters, leaf physiological indicators, and biomass allocation of the two Carex species were significantly affected (p<0.05). Both Carex species increased their investment in leaf biomass, maintained lateral root growth, and cleared reactive oxygen species to maintain their physiological balance. (c) In the simulated urban low-light environment, neither C. parva nor C. scabrirostris produced dauciform roots. In terms of response strategies, C. scabrirostris is a high-photosynthesis investing species with high productivity under low-light conditions, whereas C. parva exhibits minimal response, indicating a slow investment. C. scabrirostris has greater potential for application in low-light environments compared to C. parva. These results provide a theoretical basis for the cultivation and application of these two Carex species, as well as the expansion of turfgrass germplasm resources.

A simple method to map pollination ecosystem services potential in urban lawns

Urban areas have detrimental impacts on the ecosystems. Nevertheless, they still supply many ecosystem services (ES), such as Pollination, in different urban green spaces (UGS). Lawns are among the most degraded UGS due to very high human impact. Still, flowers such as Dandelions (Taraxacum officinalis) live in these spaces. These flowers are considered a suitable habitat for pollinators. In this work, we develop a methodology to map Pollination ES potential in urban lawns using an Unmanned Aerial Vehicle. A detailed protocol was developed using high-resolution images, consisting of orthomosaic creation, flower vectorisation, field validation, and finally, Pollination ES potential mapping using Kernel and Point Density. This method can be applied to urban lawns and grasslands in Spring and Summer.•A novel method was developed to map pollination potential in lawns.•Dandelions (Taraxacum officinale) were mapped using UAV high-resolution images.•The method is helpful to identify areas with pollination potential in urban lawns.

A simple method to assess flood regulation supply in urban lawns

Floods have an important impact on life and loss of goods. Urban green spaces are crucial to mitigating flood impact. However, their capacity to prevent floods depends on their condition, especially in areas highly affected by human activities such as lawns. Here, we developed a simple method to assess flood regulation using soil penetration resistance as a proxy and tested it on an urban lawn in Vilnius (Lithuania) in winter. We developed an experimental design using an app for collecting data and working with it in a GIS environment. To understand their spatial relations, geostatistical (e.g., semi-variogram model and ordinary kriging mapping) and spatial statistics ((Moran's global autocorrelation index and Cluster and Outlier Analysis (Anselin Local Moran's I)) tools were applied. The preliminary results from the tested method showed that the lawn studied has different capacities to retain floods due to the management practices. Nevertheless, it is essential to be applied in different soil moisture conditions since flood regulation (soil penetration resistance) can be variable throughout the year.•A novel method was developed to estimate flood regulation using soil penetration resistance as a proxy;•An urban lawn was used to test the method and identify areas with low and high capacity for flood regulation;•The method quickly assesses lawn flood retention capacity in different environments.

Adding a mosaic mowing regime to urban lawns is the key to city biodiversity management for pollinators

City populations are growing rapidly, with built-up areas occupying ever-larger areas within the cities. One of the last green places in a city is urban lawns. Our study aimed to investigate how lawn management changes can contribute to improving insect pollinator biodiversity at the city scale. Over two years, we studied dozens of urban lawns in Prague (Czech Republic) that were partially left unmown, and we selected three major groups of pollinators: Lepidoptera, Coleoptera and Hymenoptera. This study showed that leaving unmown lawn areas has a strong positive effect on insect biodiversity. The high intensity of lawn flowering through the vegetation season was also crucial. Our research showed that leaving unmown parts of urban lawns is one of the key amendments to maintain or even increase pollinator biodiversity in cities. It also appears to be the best way to attract red-listed species. A significant reducing mowing frequency to achieve a higher flowering intensity should be a positive solution. So-called insect gardening by reducing urban lawn mowing frequency or leaving parts of lawns completely unmown can help not only pollinators but also other animals that find food or shelter in them. This management will also enable the propagation of flowering plants. Additionally, biodiversity measures coincide with reducing evapotranspiration and thus cooling urban heat islands.

Biodiversity of plants in suburban meadows to create urban lawns with wildflowers

The creation of natural lawns is a means of optimizing costs for maintaining green infrastructure in the city by including natural biodiversity in lawns, which will increase the stability of plant communities in lawns and the quality of ecosystem services. Purpose. Determine the predominant species of plant groups of natural phytocenoses, which are further appropriate for planting in semi-natural lawns to ensure the stability of territories.. Methods. The Ramensky method was employed to determine the quantitative composition of natural lawns in the study areas, while the Raunkiær classification was utilized to identify persistent and perennial plant species. Results. The geobotanical investigation enabled the identification of dominant species in the study areas, providing insights into the phytocoenological composition of natural lawns for the city of Kyiv. This served as the foundation for developing recommendations for a plant catalogue tailored to the creation of such lawns in Kyiv. The grass stand at Lysa Hora exhibited the highest stability, with a significant presence of native species. Adventitious species were less dominant in this area, likely due to their conditional pathogenicity. Conversely, Trukhaniv Island displayed dominance by typical species, albeit with the occasional presence of azonal species. Mount Shchekavytsia showed competition between azonal and typical species. Surveys of recreational areas, including Lysa Hora, Mount Shchekavytsia, and Trukhaniv Island, underscored the presence of native, azonal, and adventive species. The study identified common native hemicryptophytes, including filamentous fescue, grey fescue, and creeping wheatgrass. A developed plant catalogue is poised to enhance ecosystem regulation services, such as microclimate regulation, water and wind erosion control, biodiversity maintenance, and social services through increased territorial attractiveness. Conclusions. When creating a natural lawn, the best species are considered to be indigenous, which allows for the sustainability of plant communities. The study identified the following native species that will successfully complement lawn coverings in the city: gray and filamentous fescue, ground fescue, creeping thyme, green strawberry, field carnation, and oak sage. The recommendations can be applied in other cities of Ukraine with similar physical and geographical conditions.

Evaluating the impact of natural products to improve the sustainability or urban lawns

It is known that natural products can be used to strengthen and minimise stress of the gardening and sportive lawns, thus reducing the required inputs. In this paper, a trial is designed that allows for the study of the effect of a combination of two biostimulants and water-retaining agent products on different types of lawns. During 6 months, including the summer, soil and plant parameters are evaluated to compare the effects of treatments on soil temperature, humidity, and electrical conductivity, along with the NDVI of the grasslands. Treatment with the water-retaining agent and the second tested biostimulants has increased soil moisture by 10 %, with a greater effect on ornamental grasslands with lower maintenance requirements than sports lawns. The treatments with the two biostimulants without the water retaining agent do not lead to a significant variation in the aspect of the lawn. Marginal increases in the NDVI have been observed in all the treatments, which include the biostimulants. According to these results, it is possible to achieve better water efficiency in managing urban lawns by using natural products, which leads to a more sustainable use of hydric resources.

Impact of urban diets on the nutritional physiology of mealworms

Mealworms ( Tenebrio Molitor), the larval stage of yellow mealworm beetles, are a popular feeder insect for birds, amphibians, reptiles, fish, and even human populations throughout the world. As such, the goal of this work was to understand how the diet of mealworms impacts their nutritional quality as variations in quality can impact the animals (and humans) that consume them. We hypothesized that the nutritional quality of mealworms would be altered by dietary intake with urban substrates resulting in reduced nutritional quality. We divided 500 mealworms among each of the following diets designed to model substrates available in urban vs rural, more natural areas: 100% wheat germ (control); 100% Styrofoam; mixture of soil, grasses, and leaves from urban lawns; mixture of soil, grasses and leaves from rural lawns; mixture of wheat germ + carrots; natural organic fertilizer; or natural organic fertilizer with turf builder. The mealworms were maintained at room temperature and the diets were replaced weekly to prevent spoilage and to remove mealworm wastes. Once a week for three weeks, mealworms were sampled and frozen. Data were analyzed by two-way ANOVA with time and substrate as factors. After 3 weeks, mealworms housed in wheat germ + carrots weighed significantly more than all other groups (p&lt;0.05), whereas those housed in styrofoam or urban lawn substrates weighed significantly less at week 3 as compared to week 1 (p&lt;0.01). The urban lawn substrate resulted in greater molting and the highest number of pupae, but also the greatest mortality among the substrates. Moreover, mealworms provided urban lawn weighed less at week 3 as compared to week 1 (p=0.006). Mealworms maintained on wheat germ had significantly greater total protein content (p&lt;0.05) and the greatest increase in protein content from week 0 to week 3 as compared to any other diet (p&lt;0.05). Glucose content, on the other hand, was significantly lower in all groups at week 3 compared to week 0 (p&lt;0.05). Similar trends were seen in total soluble sugars as mealworms housed in styrofoam, urban lawn, rural lawn, natural fertilizer, and fertilizer with turf builder had lower levels of total soluble sugars at week 3 compared to baseline (p&lt;0.03) whereas those fed wheat germ, with or without carrots, had the highest content (vs WG: p≤0.03; vs WGCAR p&lt;0.05). Interestingly, mealworms housed in wheat germ had higher oxidized lipoproteins compared to all other groups (p&lt;0.05) whereas those fed natural fertilizer or wheat germ and carrots had the lowest level of oxidative stress compared to baseline (p&lt;0.05). Together, these variations support our hypothesis that the nutritional quality of mealworms is altered by dietary intake. In general, urban substrates reduced the nutritional content (body mass, protein, and sugar content) of mealworms, which may negatively impact the health and behavior of predators that rely on such prey for food. This study was funded in part by a Jumpstart Grant awarded to RL by the Graduate and Professional Student Association, Arizona State University. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Assessment of the Effects of Autonomous Mowers on Plant Biodiversity in Urban Lawns

Gaining information on the impact of lawn management with autonomous mowers on the floristic composition is crucial to improve their plant biodiversity. In this study, an autonomous mower with a reduced mowing frequency and a more sporadic mowing management system with a ride-on rotary mower were compared in terms of the effect on three dicotyledonous species (Phyla nodiflora, Lotus corniculatus and Sulla coronaria) transplanted onto stands of Bermuda and Manila grass. Regardless of the management system, P. nodiflora achieved the best results in terms of survival for both lawns (74.92 and 58.57% in Manila and Bermuda grass, respectively). In Bermuda grass, a higher percentage of surviving individuals was observed for the ordinary mower management system (42.59%), rather than with the autonomous mower (9.10%), while no differences emerged on Manila grass. On both Manila and Bermuda grass, a higher average percentage of coverage for single individual was observed for the ordinary mower management system (1.60 and 0.37%, respectively) compared to the autonomous mower system (0.55 and 0.08%, respectively). P. nodiflora had a higher percentage of individuals with flowers with the ordinary management system rather than with autonomous mower system both on Manila (60.73% and 33.90%, respectively) and Bermuda grass (48.66 and 3.32%, respectively). Despite a lower impact on the planted species being observed for the ordinary mower management system, encouraging results were obtained with the autonomous mower, for instance regarding the percentage of surviving individuals for P. nodiflora (33.95%) and L. corniculatus (22.08%) on Bermuda grass and the percentage of individuals with flowers for the same two species (33.90 and 13.59%, respectively) on Manila grass. Furthermore, the autonomous mower management system’s primary energy consumption over the year was lower compared to that of the ordinary system both on Manila (200.4 and 614.97 kWh ha−1 year−1, respectively) and Bermuda grass (177.82 and 510.99 kWh ha−1 year−1, respectively).

Urban lawn vegetation structure impact arthropod abundance and cattle egret foraging success

The vegetation in urban green spaces is often managed by means of machines and/or pesticides including herbicides for aesthetics without regard to the potential consequences on arthropods, particularly insect abundance, and the animals, especially birds, that feed on insects and other arthropods. Using the green spaces on the University of Cape Coast campus and cattle egrets (Bubulcus ibis) that feed there as a test case, we investigated the influence of arthropod abundance and vegetation structure on the foraging success of cattle egrets. To achieve this, we measured the foraging efficiency (FE) and capture rate (CR) of cattle egrets, and their correlations with arthropod abundance, vegetation height, vegetation cover, and mode of vegetation clearing during the wet and dry seasons. Foraging cattle egrets were surveyed along seven permanent transects three times for each season. Using sweep nets and pitfall traps, arthropods were sampled at six randomly selected locations within each transect where cattle egrets were recorded. General linear models showed that arthropod abundance did not differ between seasons and was positively correlated with FE but not with CR. Moreover, arthropod abundance was positively related to the number of days since vegetation clearing but not to vegetation height, vegetation cover, or vegetation clearing method. Vegetation height and vegetation cover were negatively correlated with CR but not with FE. Also, CR was significantly higher in machine-cleared areas than in cutlass-cleared areas. Collectively, these findings highlight the influence of vegetation management practices, particularly machine-clearing, on arthropod abundance and its implications for avian foraging success in urban green spaces. The relationship between arthropod abundance and foraging efficiency emphasizes the importance of sustainable vegetation management strategies to support bird populations in urban environments.

Lawns and meadows in urban green space – a comparison from perspectives of greenhouse gases, drought resilience and plant functional types

Abstract. Today, city planners design urban futures by considering environmental degradation and climate mitigation. Here, we studied the greenhouse gas fluxes of urban lawns and meadows and linked the observations with plant functional types and soil properties. In eight lawns and eight meadows in the Helsinki metropolitan area, Finland, carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes were measured using manual chambers, and plant functional types were recorded. Four of these sites, i.e. an irrigated lawn, an old mesic meadow, a non-irrigated lawn and a young dry meadow, were more intensively studied in 2021–2022. The process-based ecosystem model JSBACH was utilized together with the momentary observations collected approximately every second week on CO2 exchange to quantify the annual carbon (C) balance of these sites. On the remaining sites, we studied the initial dynamics of conversion from lawns to meadows by transforming parts of lawns to meadows in late 2020 and conducting measurements from 2020 to 2022. The mean photosynthetic production (GPP) of the irrigated lawn and mesic meadow was the highest in this study, whereas the dry meadow had the lowest GPP. The studied lawns were stronger C sinks compared to the meadows. However, the net exchange values were uncertain as the soils were not in equilibrium with the vegetation at all sites, which is common for urban habitats, and modelling the heterotrophic emissions was therefore challenging. The conversion from a lawn to a meadow did not affect the fluxes of CH4 and N2O. Moreover, the mesic meadow was more resistant to drought events than the non-irrigated lawn. Lastly, the proportion of herbaceous flowering plants other than grasses was higher in meadows than in lawns. Even though social and economic aspects also steer urban development, these results can guide planning when considering environmentally friendlier green spaces and carbon smartness.

The Lawn as a Social and Cultural Phenomenon in Perth, Western Australia

Lawns, introduced in Australia through English colonial heritage, dominate public spaces in cities, serving various ecosystem functions. Australian lawns consist of non-native grasses that differ from native original vegetation and require intensive management and maintenance. This study explores public perspectives on urban lawns in Perth, Western Australia, an area largely overlooked in ecological and social research in the context of Australia compared to Europe and North America. This paper presents empirical research on public perceptions of urban lawns and alternatives in Perth, Western Australia. The study explores social values and preferences regarding traditional lawns and new options, considering visual appearance, uses, and maintenance. Findings from an online questionnaire, involving 171 respondents, identified seven categories based on a content analysis of lawn definitions: flat area; ground covered by grass; maintained; non-native vegetation; open space; recreational space; and turf grass. The results revealed that respondents most value lawns for aesthetics, cooling and recreation (exercises, walking pets, as a transit area, passive recreation, and social gatherings). At the same time, participants demonstrated an environmental awareness of lawns and the necessity of revisiting the existing planning and maintenance routine based on irrigation and intensive mowing by considering several alternative solutions. While valuing new solutions such as Scaevola patches in dedicated areas and “weedy lawns”, participants still preferred alternatives closest in appearance to a conventional lawn (e.g., lawn grass with Dichondra and lawn grass with clover). The study emphasizes the need for a ‘blended model’ of urban lawns, combining durability with heat-resistant, biodiverse vegetation to address social values and environmental concerns.

Metal pollution drives earthworm biodiversity in urban lawns

Urban soils represent hotspots of metallic trace elements (MTEs) pollution. Despite the critical impact of soil organisms on soil ecosystem services, there is limited understanding regarding the effects of MTE levels in urban soils on these organisms. This is particularly surprising considering that earthworms, key organisms for soil ecosystems, are commonly used in MTE toxicity tests. This research investigates the impact of MTE pollution on earthworm communities in lawns within the city of Paris. In this study, we sampled a comprehensive array of earthworm communities, totalling 965 individuals from 13 distinct species belonging to Lumbricus, Aporrectodea, Allolobophora and Octolasion genera. These communities were collected from three different locations within 18 parks. At these sites, we assessed the concentrations of eight metals and metalloids in the soil (As, Cd, Cr, Cu, Zn, Ni, Pb and Hg), along with selenium concentrations and eight fundamental soil parameters, to examine the association between earthworm communities and soil attributes. Median MTE concentrations exceeded recommended statutory limit values by approximately 20 % (0.6 mg/kg Cd), 30 % (36.8 mg/kg Cu), 40 % (122.0 mg/kg Zn), and up to 90 % (0.6 mg/kg Hg and 99.7 mg.kg Pb). Nevertheless, these concentrations exhibited considerable variability both between and within parks, correlating with variations in earthworm community structures. Specifically, our results highlight that Cu concentrations in the soil explain about 6 % of the variation in the assemblage of earthworm species. Our findings underscore the importance of considering MTE pollution levels to enhance our comprehension of earthworm distribution in urban environments and its effects on the ecosystem services provided by urban lawns.

Assessing the Impact of Water Conservation on Cooling Potential of Two Turfgrass Species

Highlights Empirical CWSI was developed for 'Westcoaster' tall fescue and ‘Tifgreen’ hybrid bermudagrass. The canopy temperature of both species was monitored under multiple irrigation scenarios. Deficit irrigation might reduce the cooling benefits of irrigated urban lawns. Abstract. Canopy temperature provides valuable information for efficient irrigation management and for detecting drought injury in a fast and non-destructive way. It also helps quantify the trade-offs between water conservation and the cooling benefit of the irrigated urban landscape, a critical issue in semiarid inland southern California with limited available water resources. Two adjacent hybrid bermudagrass and tall fescue irrigation trials were conducted to determine canopy temperature changes under a wide range of irrigation treatments from 2017 to 2019 in Riverside, California, USA. The canopy temperature data were also used to develop an empirical crop water stress index (CWSI) for each species. The CWSI values ranged from -0.15 to 0.71 for tall fescue and from -0.28 to 0.54 for hybrid bermudagrass. We observed a moderate correlation between visual rating scores (VR) and CWSI values for tall fescue (r = -0.68) and hybrid bermudagrass (r = -0.61). The fitted linear regression between VR and CWSI data suggested CWSI thresholds close to zero for both species to maintain their acceptable visual quality. The irrigation level consistently showed a significant effect on canopy temperature for both species. On average, a 10% decrease in irrigation application increased the canopy temperature of tall fescue and hybrid bermudagrass by 1.3°C and 0.9°C, respectively. Therefore, deficit irrigation might reduce the cooling benefits of irrigated urban lawns in the semiarid climate of inland southern California. Keywords: Canopy temperature, Evapotranspiration, Smart irrigation controller, Urban heat island, Urban irrigation, Water conservation.

Application of synanthropic plants in the design of green spaces in Warsaw (Poland)

Abstract The aim of the study was to summarize the use of synanthropic vegetation in public green areas of selected Polish cities. The study included issues related to phytosociology and landscape architecture. For this purpose, a literature study was performed. Part 1 identified possible ways of using synanthropic vegetation in the design of public green areas, Part 2 showed examples of such areas from Warsaw. The authors suggested species that can help enrich urban lawns, part 3 contains proposition of plant species composition for more natural lawns in city parks, including synanthropic plants typical for Poland (prepared by the authors). The process of gradual introduction of synanthropic vegetation in Poland was summarized and compared to the trends in Western European countries. The urban policy of Warsaw regarding the mowing of lawns and the use of flower meadows was briefly described, which influences the presence of synanthropic species in the urban environment. A watershed moment for the use of synanthropic species in Poland was identified, as well as the authors‘ predictions for their future use.

Development of sandy soil properties within subtropical residential landscapes

Urbanization is homogenizing residential developments and soils across a wide climate gradient of the United States. Land development practices commonly install landscapes on low-quality compacted fill material. While previous research shows that soil quality beneath urban lawns improves over time, studies used golf courses to represent lawns or sampled across variable development and management styles. Limited data on sandy soil quality within residential landscapes in subtropical climate warranted investigation. To evaluate the effect of age on residential soil characteristics, two residential developments from Central and Southwest Florida were selected based on known lot ages up to 31 years. Soil samples (0 to 30 cm) were collected from landscape beds and lawns, along with lawn of common areas, to evaluate bulk density and organic matter over time. Though landscape beds typically require less management, soil characteristics were similar between lawns and landscape beds, suggesting similar processes. Bulk densities decreased by 22–34% and 9–20% within the upper (0–15 cm) and lower (15–30 cm) soil depths, respectively. Upper layer soil carbon accumulation rates ranged from 0.060 to 0.156 kg C m−2 yr−1, comparable to previous studies but did not exceed 0.021 kg C m−2 yr−1 or were not significant for greater depths. The results of this study are representative of past chronosequence studies conducted in cooler climates with fine soil texture. Sandy soil texture and warm climate do not govern carbon sequestration rates, but instead vegetation type and landscape management practices overcome these conditions.