Rainfall Interception by Urban Trees and Their Impact on Potential Surface Runoff

Three types of indirect watering devices were compared to evaluate their performance and to determine their benefits to newly transplanted river birch (Betula nigra) trees grown in containers with well drained compost in a controlled greenhouse experiment. Two examples of each device type were used to water trees in this study: upright bags, ring bags, and open tubs. Watering device characteristics, including purchase cost, weight, capacity, and drainage times, were measured prior to installing the devices around the trees. Tree stem heights and calipers, along with leaf coverage and leaf water potential, were measured to determine any growth or water stress differences associated with watering treatments. There was substantial variation in costs and drainage times among watering devices, with ring bags being the least expensive and draining water completely during the drainage test. However, there was no evidence that watering devices benefited tree growth, leaf rating, or water stress in comparison with direct watering, with the possible exception of Treegator ring bags, which may have reduced water stress marginally. Although water release from some of the indirect watering devices was much slower than direct watering, water release from all of the devices was completed within ten hours, which is too rapid to reduce the frequency of watering in our experiment. The major benefits of these devices are slower release of water to the soil, with reduced operator time required, and more infiltration into the soil and root zone, which avoids the surface runoff caused by quick hose (direct) watering.

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Evaluating the Influence of Rain Event Characteristics on Rainfall Interception by Urban Trees Using Multiple Correspondence Analysis

Water ◽

10.3390/w11122659 ◽

2019 ◽

Vol 11 (12) ◽

pp. 2659

Author(s):

Katarina Zabret ◽

Mojca Šraj

Keyword(s):

Correspondence Analysis ◽

Multiple Correspondence Analysis ◽

Regression Trees ◽

Pinus Nigra ◽

Rainfall Amount ◽

Urban Trees ◽

Boosted Regression Trees ◽

Rain Event ◽

Rainfall Interception ◽

Pine Tree

Urban trees play an important role in the built environment, reducing the rainfall reaching the ground by rainfall interception. The amount of intercepted rainfall depends on the meteorological and vegetation characteristics. By applying the multiple correspondence analysis (MCA), we analysed the influence of rainfall amount, intensity and duration, the number of raindrops, the mean volume diameter (MVD), wind speed and direction on rainfall interception. The analysis was based on data from 176 events collected over more than three years of observations. Measurements were taken under birch (Betula pendula Roth.) and pine (Pinus nigra Arnold) trees located in an urban park in the city of Ljubljana, Slovenia. The results indicate that rainfall interception is influenced the most by rainfall amount and the number of raindrops. In general, the ratio of rainfall interception to gross rainfall decreases with longer and more intense rainfall events. The influence of the raindrop number depends also on their size (MVD), which is evident especially for the pine tree. For example, pine tree interception increases with smaller raindrops regardless of their number. In addition, MCA gives a new insight into the influence of wind characteristics, which was not visible using previous methods of data analysis (regression analysis, correlation matrices, regression trees, boosted regression trees). According to the nearby buildings, a wind corridor is sometimes created, decreasing rainfall interception by both tree species.

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An urban ecohydrological model to quantify the effect of vegetation on urban climate and hydrology (UT&C v1.0)

10.5194/gmd-2019-225 ◽

2019 ◽

Cited By ~ 1

Author(s):

Naika Meili ◽

Gabriele Manoli ◽

Paolo Burlando ◽

Elie Bou-Zeid ◽

Winston T. L. Chow ◽

...

Keyword(s):

Air Temperature ◽

Surface Runoff ◽

Urban Climate ◽

Well Being ◽

Urban Trees ◽

Outdoor Thermal Comfort ◽

Simultaneous Increase ◽

Ground Vegetation ◽

Area Index ◽

Ecohydrological Model

Abstract. Increasing urbanization is likely to intensify the urban heat island effect, decrease outdoor thermal comfort and enhance runoff generation in cities. Urban green spaces are often proposed as a mitigation strategy to counteract these adverse effects and many recent developments of urban climate models focus on the inclusion of green and blue infrastructure to inform urban planning. However, many models still lack the ability to account for different plant types and oversimplify the interactions between the built environment, vegetation, and hydrology. In this study, we present an urban ecohydrological model, Urban Tethys-Chloris (UT&C), that combines principles of ecosystem modelling with an urban canopy scheme accounting for the biophysical and ecophysiological characteristics of roof vegetation, ground vegetation and urban trees. UT&C is a fully coupled energy and water balance model that calculates 2 m air temperature, 2 m humidity, and surface temperatures based on the infinite urban canyon approach. It further calculates all urban hydrological fluxes, including transpiration as a function of plant photosynthesis. Hence, UT&C accounts for the effects of different plant types on the urban climate and hydrology, as well as the effects of the urban environment on plant well-being and performance. UT&C performs well when compared against energy flux measurements of eddy covariance towers located in three cities in different climates (Singapore, Melbourne, Phoenix). A sensitivity analysis, performed as a proof of concept for the city of Singapore, shows a mean decrease in 2 m air temperature of 1.1 °C for fully grass covered ground, 0.2 °C for high values of leaf area index (LAI), and 0.3 °C for high values of Vc,max (an expression of photosynthetic activity). These reductions in temperature were combined with a simultaneous increase in relative humidity by 6.5 %, 2.1 %, and 1.6 %, for fully grass covered ground, high values of LAI, and high values of Vc,max, respectively. Furthermore, the increase of pervious vegetated ground is able to significantly reduce surface runoff. These results show that urban greening can lead to a decrease in urban air temperature and surface runoff, but this effect is limited in cities characterized by a hot, humid climate.

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Modelling rainfall interception by urban trees

Canadian Water Resources Journal / Revue canadienne des ressources hydriques ◽

10.1080/07011784.2017.1375865 ◽

2017 ◽

Vol 42 (4) ◽

pp. 336-348 ◽

Cited By ~ 6

Author(s):

Jie Ying Huang ◽

T.A. Black ◽

R.S. Jassal ◽

L.M. Les Lavkulich

Keyword(s):

Urban Trees ◽

Rainfall Interception

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Modified NRCS Abstraction Method for Flood Hydrograph Generation

10.22541/au.160923930.05876665/v1 ◽

2020 ◽

Author(s):

Jaber Almedeij

Keyword(s):

Surface Runoff ◽

Water Retention ◽

Potential Surface ◽

Initial Moisture Content ◽

Curve Number ◽

Actual Surface ◽

Time Of Concentration ◽

Initial Abstraction ◽

Flood Hydrograph ◽

Selection Of

The NRCS abstraction method is based on two assumptions. The first is that the ratio of actual water retention after ponding to maximum potential retention after ponding is equal to the ratio of actual surface runoff to potential surface runoff. The second assumption is that the initial abstraction for the watershed is twenty percent of the maximum potential retention. This study shows that both assumptions violate continuity principles and proposes a modification that renders an elementary relationship accounting for all abstraction forms by dividing them into a variable and constant components. Consequently, the surface runoff computation becomes dependent on the soil initial moisture content and implicitly influenced by the initial abstraction, while retaining the advantage of the subjective selection of curve number from extensive database from which the NRCS method has gained popularity. A new time of concentration model is also proposed to extend the computation for flood hydrograph generation.

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Land-Use Land-Cover Change and Its Impact on Surface Runoff using Remote Sensing and GIS

International Journal of Advanced Remote Sensing and GIS ◽

10.23953/cloud.ijarsg.237 ◽

2017 ◽

Vol 6 (1) ◽

pp. 2103-2113 ◽

Cited By ~ 1

Author(s):

Prakash C.R. ◽

◽

Sreedevi B. ◽

Keyword(s):

Remote Sensing ◽

Land Use ◽

Land Cover ◽

Land Cover Change ◽

Surface Runoff ◽

Remote Sensing And Gis ◽

Land Use Land Cover

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Pengaruh Penambahan Abu Kayu Dan Abu Bambu Terhadap Kepadatan Tanah Lempung

Jurnal Manajemen Teknologi & Teknik Sipil ◽

10.30737/jurmateks.v3i2.1077 ◽

2020 ◽

Vol 3 (2) ◽

pp. 191

Author(s):

Vella Maulina Kris Putri ◽

Agata Iwan Candra ◽

Ahmad Ridwan

Keyword(s):

Surface Runoff ◽

Clay Soil ◽

Wood Ash ◽

Road Surface ◽

Plastic Limit ◽

Test Items ◽

Native Soil

The soil has an important role in construction, namely as the loading of soil on clay. It is necessary to improve the nature of the shrinkage. The authors conducted the study to increase the strength of clay by adding wood ashes and bamboo ashes. Wood ash and bamboo ash have pozzolan properties expected to add power to clay when weighted, would drop significantly. Material compares in this study using a mix of wood ash and bamboo ash with a variation of 0%, 4%, 8%, and 12%. Meanwhile, the clay soil is taken directly from the ravaged area, from bulging villages, from the grid district. The results showed that the soil is categorized as montmorillonite soil with properties that can damage light structures and road surface runoff. After adding wood and bamboo ash, it showed optimum results of 12% of the dry fixed test items showing a liquid limit’s value at 41,00%, plastic limit at 28,43%, and the net value of plastic limit at 12,57%. When testing for solidification using native soil at a dry volume of 7,91, gr/cm rainfall can increase by 10,42 gr/cm additives after adding 12% of wood ash and bamboo ash.Tanah memiliki peran penting dalam konstruksi yaitu sebagai pembebanan tanah pada tanah liat. Perlu untuk memperbaiki sifat penyusutan. Penulis melakukan penelitian untuk meningkatkan kekuatan tanah liat dengan cara menambahkan abu kayu dan abu bambu. Abu kayu dan abu bambu memiliki sifat pozzolan yang diharapkan dapat menambah kekuatan pada tanah liat saat tertimbang, akan turun secara signifikan. Perbandingan material dalam penelitian ini menggunakan campuran abu kayu dan abu bambu dengan variasi 0%, 4%, 8%, dan 12%. Sementara itu, tanah lempung diambil langsung dari area yang rusak, dari desa-desa yang menggembung, dari grid distrik. Hasil penelitian menunjukkan bahwa tanah tersebut dikategorikan sebagai tanah montmorillonite dengan sifat yang dapat merusak struktur ringan dan aliran permukaan jalan. Setelah dilakukan penambahan abu kayu dan bambu didapatkan hasil optimum dari 12% benda uji tetap kering yang menunjukkan nilai batas cair 41,00%, batas plastis 28,43%, dan nilai bersih batas plastis 12,57%. Pada pengujian solidifikasi menggunakan tanah asli pada volume kering 7,91 gr / cm curah hujan dapat meningkat sebesar 10,42 gr / cm aditif setelah penambahan 12% abu kayu dan abu bambu.

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