Pyrus calleryana

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PENGELOLAAN
HUTAN & TAMAN KOTA
Sumber:
Weber, F. , I.Kowarik dan I. Säumel. 2014. A walk on the wild side: Perceptions of roadside
vegetation beyond trees. Urban Forestry and Urban Greening, 13 (2): 205–212.
Urban nature is of vital importance for human well-being in an increasingly urbanized world.
Despite the wide variety of urban greenspaces, previous research has mostly focussed on parks
and in particular presence of trees. Although streets are fundamental urban structures and offer
an array of green elements beyond trees, the perception and valuation of other kinds of
roadside vegetation by urban residents is understudied so far. Weber, Kowarik dan Säumel
(2014) explores the range of roadside vegetation and associated ecosystem services perceived
by city dwellers in densely populated inner city districts of two German cities.
Results confirmed the important role of trees but also demonstrated that city dwellers perceive
a variety of cultivated and “wild” green components other than trees. Respondents attached a
wide range of meanings and values to roadside greenery and showed a surprisingly high
awareness of associated ecosystem services. Wild urban roadside vegetation met with high
approval, although planted and maintained vegetation was preferred.
The trees and other elements of roadside vegetation fulfil important functions in the view of the
public. For many respondents, ecological and economical functions of roadside vegetation were
more important than orderliness. This indicates opportunities for enhancing the biodiversity of
urban streetscapes. As public green spaces are in short supply in many cities, enhancing
cultivated and wild roadside vegetation could help to deliver ecosystem services in the areas
near where people move and live.
Cowett,F.D. dan N.L. Bassuk. 2014. Statewide assessment of street trees in New York State, USA.
Urban Forestry and Urban Greening, 13 (2): 213–220.
In the United States, street tree management and planning occurs at regional, state,
and local levels. However, state and federal officials charged with managing streets
trees at the regional and state levels typically lack the comprehensive, detailed
information available to local officials in a street tree inventory such as species
composition and tree size distribution. Statewide street tree assessments employing a
variety of methodologies have been conducted to fill this knowledge gap. Cowett dan
Bassuk (2014) examines these past assessments and builds upon them in conducting a
street tree assessment for New York State in which geographic variability in statewide
street tree inventory data is accounted for through weighted averaging of estimates.
Conway, T.M. dan E. Bang. 2014. Willing partners? Residential support for municipal urban
forestry policies. Urban Forestry and Urban Greening, 13 (2): 234–243.
Cities across North America are adopting ambitious goals to grow their urban forests. As existing
trees and new planting opportunities are often located on private property, residents’ support
and participation is needed in order to meet these goals. However, little research has examined
support for municipal urban forestry efforts, including policies specifically targeting residential
areas. Conway dan Bang (2014) conducted this research to (1) assess resident’ level of support
for common urban forestry policies and (2) determine if there are specific household
characteristics associated with different levels of policy support.
The majority of residents had neutral to very positive attitudes toward common municipal
policies encouraging planting and restricting removal of trees, but support levels were lower for
the policies than for general statements about desired presence and size of urban trees. Several
characteristics are significantly related to level of policy support, including age of household
members, education-level, property-level tree density, recent tree planting activity and age of
house. Interviews also highlighted residents’ apprehensions about living among tall trees and
older resident's concerns with tree maintenance.
The most residents would be willing partners in urban forestry efforts, with many of these
residents already actively planting and maintain trees. However, to increase support and
participation rates, different types of trees should be part of any planting program to meet the
varying needs of households.
Zhang, H. and C.Y. Jim . 2014. Contributions of landscape trees in public housing estates to
urban biodiversity in Hong Kong. Urban Forestry & Urban Greening, 13 (2): 272–284.
Public housing estates (PHEs) in Hong Kong, accommodating 3.3 million of the 7-million
population, have generous landscape planting in their grounds. The independent tree
management regime generates a tree stock that deviates from the general urban-tree
population. Zhang dan Jim (2014) evaluated species composition, floristic diversity, importance
value, and spatial distribution of trees in 102 PHEs (half of the total) occupying 8.31 km2
(territory land area of 1104 km2), assessed their contribution to urban biodiversity, and
developed a species selection strategy to enrich urban biodiversity. About 48,823 trees
belonged to 232 species, 151 genera and 59 families. Natives contributed 69 species and 10,837
trees. Species profile was skewed toward exotic species and trees. The species were divided into
six frequency groups.
The signature group had 45 species each with >200 trees. The dominant, common and
occasional groups had 20, 26 and 48 species, respectively. 59 species in the rare group and 34 in
the solitary group denoted changing and diverse species selections, respectively. Nonmetric
Multidimensional Scaling (NMDS) found that species distribution in PHEs was strongly
associated with species diversity, estate area and estate age. However, district and region were
not correlated with NMDS. Some 98 species were significantly correlated (Spearman) with one
or both NMDS axes. Species groups were analyzed to inform a species selection strategy to
improve future planting program and enrich urban biodiversity.
Loeb, R.E., S. King dan J. Helton. 2014. Human pathways are barriers to beavers damaging trees
and saplings in urban forests. Urban Forestry & Urban Greening, 13 (2): 290–294.
Urban North American beaver (Castor canadensis) damage of trees and saplings was
compared between shore forests and forests uphill of macadam, wood chip, and
raised wood board human pathways used daily in Radnor Lake State Natural Area,
Nashville, TN (Loeb, King dan Helton. 2014). Comparisons of beaver damage were
made between shore forests and forests uphill of bare earth deer paths used less than
once a month by humans and the forests were on 5% and 30% slopes.
Significant differences in beaver damage of trees and saplings were found between
forests uphill of the human pathways used daily and the respective shore forests.
Beaver damage of trees and saplings was not significantly different between the shore
forests and forests uphill of the deer paths used less than once a month by humans for
the 5% slope forest; however, the differences were significant for the 30% slope forest.
Beaver damage of trees and saplings was significantly greater in the uphill of the deer
paths forests than the uphill of the human pathways forests for comparable slope
forests. Human scent on the pathways used daily made of macadam, wood chips, and
raised wood boards was interpreted to be the barrier sensed by beavers to not cross
over or under the human pathways to damage trees and saplings.
Öström,E.S. , M. Nordin, Y. Lundell, A.Dolling, U. Wiklund, M.Karlsson, B.Carlberg, dan
L.S.Järvholm. 2014. Restorative effects of visits to urban and forest environments in patients
with exhaustion disorder. Urban Forestry & Urban Greening, 13 (2): 344–354.
This experimental study investigated differences in perceived restorativeness, mood,
attention capacity and physiological reactions when visiting city and forest
environments. Twenty female patients diagnosed with exhaustion disorder visited
three different forest environments and one city environment in randomized order.
They performed a standardized 90-min test procedure in each of these environments.
Evaluation of the environments and psychological effects in mood were studied with
self-administered questionnaires. Attention capacity was studied with Necker Cube
Pattern Control task. Physiological responses were measured with regularly scheduled
controls of heart rate and blood pressure, and a single test of heart rate recovery.
Visits to the forest environments were perceived as significantly more restorative,
enhancing mood and attention capacity compared to the city. This also applies to the
results of heart rate and to some extent to the results of the diastolic blood pressure.
The results from this experimental study support our hypothesis that short visits to
forest environments enhance both psychological and physiological recovery and that
visits to forest environments are likely to be beneficial when suffering from exhaustion
disorder.
Hamada, S., T. Tanaka dan T. Ohta. 2013. Impacts of land use and topography on the cooling
effect of green areas on surrounding urban areas. Urban Forestry & Urban Greening, 12 (4):
426–434.
Few studies have examined the influence of land use and terrain on the cooling effect
of green areas on surrounding urban areas. Hamada, Tanaka dan Ohta (2013)
investigated the spatial distribution of the cooling effect of green areas on surrounding
urban areas in Heiwa Park, Nagoya, central Japan, by applying surface temperature (Ts)
information obtained from Advanced Spaceborne Thermal Emission and Reflection
Radiometer (ASTER) image data. The cooling effect was found to extend in many
directions into the urban areas. The spatial distribution of Ts showed that commercial
areas interrupted the flow of park cooling, whereas other types of urban areas
expanded park cooling more effectively. We hypothesise that this was the result of
differences in geometric and thermal properties and anthropogenic heat release
between commercial and other areas. The spatial distribution of Ts also reflected the
effects of topography on park cooling. The green area at our study site was located on
a hill, and the downward slope and valley terrain inside the park increased the cooling
effect towards the surrounding urban areas. To improve the thermal environment of
urban areas and the comfort levels of residents, effective utilisation of the cooling
effect of green areas should be incorporated into urban designs that consider the
effects of land use and topography.
Sung, C.Y. 2013. Mitigating surface urban heat island by a tree protection policy: A case study of
The Woodland, Texas, USA. Urban Forestry & Urban Greening, 12 (4): 2013 474–480.
The Woodlands Township, TX, has a tree protection policy that consists of tree removal
permits and minimum tree and shrub cover regulations. Sung (2013) examined the
effect of The Woodlands’ tree protection policy on surface urban heat island (SUHI) at
the neighborhood scale by comparing the mean land surface temperatures (LSTs)
derived from 37 thermal infrared bands of Landsat TM images between The
Woodlands’ neighborhoods and nearby control neighborhoods without such a policy.
To rule out the effect of confounding factors that may influence LSTs, the control
neighborhoods were selected to be similar in physical and socioeconomic status to The
Woodlands’ neighborhoods. LSTs of The Woodlands’ neighborhoods were, on average,
1.5–3.9 °C lower than those of the control neighborhoods. The cooling effect of The
Woodlands’ tree protection policy was more prominent in summer when SUHI
mitigation was mostly needed.
The local tree protection policy is effective in mitigating SUHI at the neighborhood
scale.
Qin, J. , X. Zhou, C. Sun, H. Leng dan Z. Lian. . 2013. Influence of green spaces on
environmental satisfaction and physiological status of urban residents. Urban Forestry & Urban
Greening, 12 (4): 490–497.
Influence of urban green spaces on human was evaluated with subjective
questionnaires as well as physiological measurements. Five sample plots vary in color,
size and scent of major plants and one no-vegetation area located in Shanghai
Botanical Garden, China were chosen (Qin et al., 2013). About 249 questionnaires on
subjective satisfaction evaluation were collected; in addition to 64 visitors took the
measurement of physiological parameters like Electroencephalogram (EEG) and
Electrocardiogram (ECG). The color is one of the most important factors which affect
the overall satisfaction of people with their vegetation environment. The way how
people perceive vegetation environment was probed by PCA analysis. Age difference
analysis show children and elder people presented higher satisfaction with vegetation
environment than adults. Significant negative correlation between the ratio of lowfrequency to high-frequency (LF/HF) values in heart rate variability (HRV) analysis and
satisfaction values indicated HRV may be an effective parameter for green spaces
influence evaluation.
. Urban Forestry & Urban Greening, Volume 12, Issue 4, 2013, Pages 554–561
Variations of urban greenness across urban structural units in Beijing, China
Hua-Feng Wanga, , , Jiang-Xiao Qiub, Jürgen Breustec, Cynthia Ross Friedmand, Wei-Qi Zhoua,
Xiao-Ke Wang.
Urban structural units (USUs) are work (or similar) units in urbanized areas. In this study, USUs
based on urban land use and land cover were used to explain and compare urban ecological
conditions within Beijing. This study focused on the spatial pattern of land use for different USUs
in urban areas. The results showed that 453 USUs belong to 12 primary USUs and to 38 different
secondary USUs. The percentage of built-up area was highest in those regions with hotels, and
lowest in areas with cemeteries. The percentage of woodland area was highest in primary and
middle schools, and the lowest in entertainment plazas. The percentage of grassland area was
highest in farmland or orchards, and lowest in Siheyuan (courtyards). The percentage of green
space is highest in lands dedicated to middle and primary schools, and lowest in areas with
museums. There is no significant linear relationship between construction period and green
space percentage in Colleges/Universities (R = 0.045, p = 0.806 > 0.05) and Parks (R = 0.13,
p = 0.43 > 0.05). However, there was an inverted-U curve relationship with the relevant housing
price in the residential area, a relationship that can be described by the equation:
f = 17736.45 + 348.21x − 4.15 x2, p = 0.0022 < 0.05. This relationship implied that the socioeconomic factors like housing prices may be a factor in determining the green space pattern of
urban ecosystems in Beijing.
Koeser, A. , R. Hauer, K. Norris dan R. Krouse. 2013. Factors influencing long-term street tree
survival in Milwaukee, WI, USA. Urban Forestry & Urban Greening, 12 (4): 562–568.
Street trees are exposed to a variety of site conditions, environmental factors, and
physical disturbances which influence their survival in urban areas. Koeser et al.
(2013) study on 25 years of urban forest monitoring data from the city of Milwaukee,
WI (United States) to model the impacts of these factors on tree survival for a single
cohort of trees. Tree condition, tree size, tree species, and site attributes were
measured initially in 1979. These factors were measured again in 1989 and 2005 and
compared to construction data for the same area during the study period. Multivariate
logistic regression was used to identify factors associated with tree survival. Crossvalidation show the final model could successfully predict tree survival nearly 85% of
the time.
The tree survival varied by species. Additionally, trees were more likely to die as trunk
diameter increased, planting space width decreased in the tree lawn, and tree
condition decreased. The trees adjacent to construction were nearly twice as likely to
die as those not exposed to development and redevelopment activities.
Ugolini, F., R.Tognetti, A. Raschi, dan L. Bacci . 2013. Quercus ilex L. as bioaccumulator for heavy
metals in urban areas: Effectiveness of leaf washing with distilled water and considerations on
the trees distance from traffic. . Urban Forestry & Urban Greening, 12 (4): 576–584.
In recent years the use of plants as bioaccumulators or bioindicators has increased because
enable the prediction of pollution for monitoring purposes, even in urban environments where
traffic is a major source of heavy metals pollution. Ugolini et al. (2013) hypothesized that the
holm oak (Quercus ilex L.) is a valid trapping species for heavy metals. It is also hypothesized
that metals capture capacity by deposition on the crown is connected to the surrounding
environmental characteristics and the distance of trees from the source of pollution. This study
was conducted in the city of Florence. Holm oaks were selected in different sites near to heavy
traffic roads. Concentrations of Zn, Pb, Cd, Cu, Fe, Mn, Cr, and Ba were analyzed through two
methods: leaf washing with distilled water and leaf unwashing.
One-year-old leaves (new leaves) were also compared with previous-year leaves (old leaves).
The good capacity of this species to capture heavy metals (Pb, Fe, Mn, Cr, and Ba), particularly
due to the presence of old leaves, which enhance the crown deposition surface. Washing was
effective and it allowed testing the behaviour with regard to microelements: new leaves showed
high Cu concentration, while old leaves had high Pb concentration. The dispersion of metals
through the atmosphere was assessed through regression analysis, in two comparable gardens:
leaves at farther distance from the traffic were richer in Zn, Pb, Mn, and Ba. The physical context
of the surrounding environment was probably altering the distribution of heavy metals as
barriers to dispersion, which can reach tens of metres from the source of pollution.
Zhang, Z., Y. Lv, dan H. Pan . 2013. Cooling and humidifying effect of plant communities in
subtropical urban parks. Urban Forestry & Urban Greening, 12 (3): 323–329.
Urban vegetation has been proved to play an important role in mitigating the heat
island effect. However, it is not clear how independent small-scale plant communities
affected the microclimate. Zhang, Lv dan Pan (2013) investigated effects of fifteen
plant communities on temperature and relative humidity from November 2010 to
October 2011 in urban parks in subtropical Shenzhen City, China. The canopy density,
canopy area, tree height and the background climate conditions under plant
communities were measured. The effects of small-scale plant communities on
temperature and relative humidity were the most significant at 1400–1500 h during
the day. The temperature reduction and relative humidity increase due to small-scale
plant communities were higher in summer, followed by autumn, spring and winter. As
compared to the control open sites, the temperature reduction due to plant
communities ranged from 2.14 °C to 5.15 °C, and the relative humidity increase ranged
from 6.21% to 8.30%. We found that multilayer plant communities were the most
effective in terms of their cooling and humidifying effect, while bamboo groves were
the least effective.
Regression results revealed that four factors, namely canopy density, canopy area, tree
height and solar radiation, had significant influence on temperature reduction and
relative humidity increase.
Yang , J., J. McBride, J. Zhou, dan Z. Sun. 2005. The urban forest in Beijing and its role in air
pollution reduction. Urban Forestry and Urban Greening, 3 (2): 65–78.
Tree planting has been proposed by the municipal government as a measure to
alleviate air pollution in Beijing, the capital of China. Yang et al. (2005) analysed
satellite images and field surveys to establish the characteristics of current urban
forest in the central part of Beijing. The influence of the urban forest on air quality was
studied using the Urban Forest Effects Model. The results show that there are 2.4
million trees in the central part of Beijing. The diameter distribution of the trees is
skewed toward small diameters. The urban forest is dominated by a few species. The
condition of trees in the central part of Beijing is not ideal; about 29% of trees were
classified as being in poor condition.
The trees in the central part of Beijing removed 1261.4 tons of pollutants from the air
in 2002. The air pollutant that was most reduced was PM10 (particulate matters with
an aerodynamic diameter smaller than 10 μm), the reduction amounted to 772 tons.
The carbon dioxide (CO2) stored in biomass form by the urban forest amounted to
about 0.2 million tons.
Rahman,M.A., J.G. Smith, P. Stringer, dan A.R. Ennos. 2011. Effect of rooting conditions on the
growth and cooling ability of Pyrus calleryana. Urban Forestry and Urban Greening, 10 (3): 185–
192.
Urban forests appear to be an excellent way of mitigating the urban heat island and adapting
cities to climate change, as trees provide cooling by evapotranspiration. However, effects of
urban growing conditions on tree growth and cooling performance have not been widely
investigated. The current study addresses this shortcoming by studying the growth and leaf
physiology of the commonly planted urban tree Pyrus calleryana ‘Chanticleer’.
Rahman, et al. (2011) study between February and November, 2010 on streets in Manchester,
UK, where P. calleryana trees had been growing for five to six years under three contrasting
growth conditions: in pavement; in grass verges; and in Amsterdam soil.
Trees in Amsterdam soil had grown almost twice as fast as those in pavements, the difference
being related to their lower degree of soil compaction, and hence lower shear strength. Trees
grown in Amsterdam soil also had better performance in leaf physiological parameters such as
stomatal conductance, leaf water potential, and foliar nutrient status. Phenological observations
were also consistent with the observed differences in growth. The lower soil moisture content at
20 cm depth in Amsterdam soil also suggested there was a higher infiltration rate and more
moisture available to plant roots. The enhanced growth and physiological performance of trees
grown in Amsterdam soil meant they provided peak evapotranspirational cooling of up to 7 kW,
5 times higher than those grown in pavements.
Rahman , M.A., D. Armson, dan A.R. Ennos. 2014. Effect of urbanization and climate change in
the rooting zone on the growth and physiology of Pyrus calleryana. Urban Forestry & Urban
Greening, 13 (2): 2014 325–335.
It is well known that trees can reduce the urban heat island and adapt our cities to
climate change through evapotranspiration. However, the effects of urbanization and
anticipated climate change in the soil root rhizosphere have not been widely
investigated. Rahman , Armson, dan Ennos (2014) studied the growth and physiology
of the urban tree Pyrus calleryana grown in a factorial experiment with or without
urbanization and simulated climate change between April 2010 and December 2012 in
the Botanical Grounds of the University of Manchester, UK.
The urbanization and simulated climate change had small but contrasting effects on
tree growth and morphology. Urbanization increased tree growth by 20–30%, but did
not affect leaf area index (LAI) and showed reduced peak water loss and hence
evapotranspirational cooling. Although soil moisture content in the upper 20 cm was
higher in the urbanized plots, urbanization showed reduced sap flux density, reduced
chlorophyll a:b and delayed recovery of chlorophyll fluorescence (Fv:Fm) throughout
the experimental period.
The simulated climate change had no effect on growth but increased LAI by 10%.
Despite being more water stressed, trees grown in simulated climate change plots lost
more water both according to porometry and sap flow measurements. Simulated
climate change increased peak energy and water loss by around 13%, with trees
Gill, S.E., M.A. Rahman, J.F. Handley, dan A.R. Ennos . 2013. Modelling water stress to urban
amenity grass in Manchester UK under climate change and its potential impacts in reducing
urban cooling. Urban Forestry and Urban Greening, 12 (3): 350–358.
It is well known that the evapotranspiration of vegetation such as grass can help to
reduce the urban heat island. However, the cooling can be reduced or lost in summer
droughts, when soils dry out, an effect that is likely to be more pronounced and occur
for longer as climate change proceeds. Gill et al. (2013) modelled the likely effect of
climate change on the droughting of amenity grass in Greater Manchester, UK. The
simple Bucket model was used with data on Greater Manchester's soils, and its
current and anticipated precipitation and potential evapotranspiration. This was
experimentally validated by measuring the weight loss of ryegrass turves.
The dramatic increase in drought, especially in the drier south west of the
conurbation, with some areas exhibiting reduced evapotranspiration for 3–5 months
by the 2080s, and evapotranspiration reducing by over a half for 1–2 months, in an
average year. Such changes could have large effects on the urban heat island, resulting
in increases in surface temperatures of up to 15 °C in areas where grass accounts for a
large proportion of the surface cover. This problem could be overcome by irrigation of
grassland so that it will continue to provide cooling, and it is shown that runoff from
large rainfall events could in theory provide adequate irrigation water, particularly in
highly built-up areas.
Vidrih, B. dan S. Medved. 2013. Multiparametric model of urban park cooling island. Urban
Forestry & Urban Greening, 12 (2): 220–229.
Vidrih dan Medved (2013) studied mitigation of the heat island effect in the built environment with urban
(city) parks. The park cooling island (PCI) effect, considering park grass cover and trees’ density and age, is
determined for selected extreme summer days at various wind speeds under the optimum soil water
conditions in the root zone based on an all-day quasi-stationary thermal response. PCI was determined
numerically by coupling a CFD model of an urban park and quasi-steady state, two-zone thermal response
boundary condition models of each park element. The boundary models are evaluated in form of multiparameter approximation polynomials taking into account the sensible and latent heat transfer and the
geometrical, optical and thermal properties of park elements. Three-dimensional CFD modelling was used
for the determination of temperature, humidity and air velocity fields in an urban park with a size of
140 m × 140 m. Based on the comparison of the measured and numerically determined air temperatures in
the tree crowns, we proved that the method of linking the models is adequate for temperature and flow
condition modelling in the city park environment.
The results are presented in the form of local PCI as the difference between local air temperature in the
pedestrian zone and the reference air temperature preceding the park. The study proved that it is possible
to normalise the cooling effect using the specific dimensionless coefficient of leaf area (LAIsp), which includes
an approximation of the density of trees planted in the park and their size or age. It was found out that the
cooling effect of the park is up to −4.8 °C at LAIsp, equal to 3.16, which corresponds to a planting density of
45 trees per hectare, with an age of 50 years. It was also found that with the length of the park cooling effect
change decreases. The optimal length of the park with a LAIsp 3 is 130 m.
. Urban Forestry & Urban Greening, Volume 10, Issue 3, 2011, Pages 193–204
Predicting urban forest growth and its impact on residential landscape water demand in a
semiarid urban environment
John H. Lowry Jr.a, , , R. Douglas Ramseyb, , Roger K. Kjelgren.
We present an innovative approach to estimating residential irrigation water demand for a large
metropolitan area using GIS data, weather station data, and a water budget modeling approach commonly
used by plant scientists and landscape management professionals. An important question addressed by our
study is how a growing urban forest affects the overall irrigation water demand of a semiarid metropolitan
area. To estimate the amount of water required by residential landscaping, we consider water demand to be
a function of the areal extent of residential landscaping (i.e. tree/shrub or turf grass), the water-loss rate for
different landscaping types, the efficiency with which the landscape is irrigated, and local climatic factors
(i.e. reference evapotranspiration and precipitation). We estimated irrigation water demand for 542
residential neighborhoods in Salt Lake County, UT, USA for 2005. To investigate the effects of a maturing
urban forest on water demand, we used simultaneous autoregression (SAR) models to predict the spatial
extent of future forest canopy and future exposed turf grass in residential neighborhoods. For both the
forest canopy model and the turf grass model we used the median age of housing stock as the dependent
variable. Psuedo R2 were 0.70 and 0.82 for the tree/shrub canopy and turf grass models, respectively. Based
on projected areal extents of tree/shrub canopy, exposed turf grass, and turf grass under canopy, we
estimated future water demands for the 542 residential neighborhoods. Our predictive model suggests that
as urban tree canopy increases in residential urban areas, exposed turf grass decreases, with a net effect of a
slight decrease in residential landscape water demand. This can be explained by the relative differences in
water lost through evapotranspiration by different landscape types, namely; trees/shrub (i.e. woody plants),
exposed turf grass, and turf grass under tree canopy.
Armson, D., P. Stringer dan A.R. Ennos. 2013. The effect of street trees and amenity grass on
urban surface water runoff in Manchester, UK. Urban Forestry & Urban Greening, 12 (3): 282–
286.
It is well known that the process of urbanization alters the hydrological performance of
an area, reducing the ability of urban areas to cope with heavy rainfall events. Previous
investigations into the role that trees can play in reducing surface runoff have
suggested they have low impact at a city wide scale, though these studies have often
only considered the interception value of trees.
Armson, Stringer dan Ennos (2013) assessed the impact of trees upon urban surface
water runoff by measuring the runoff from 9 m2 plots covered by grass, asphalt, and
asphalt with a tree planted in the centre. The grass almost totally eliminated surface
runoff; trees and their associated tree pits reduced runoff from asphalt by as much as
62%. The reduction was more than interception alone could have produced, and
relative to the canopy area was much more than estimated by many previous studies.
This was probably because of infiltration into the tree pit, which would considerably
increase the value of urban trees in reducing surface water runoff.
. Urban Forestry & Urban Greening, 11, Issue 3, 2012, Pages 245–255
The effect of tree shade and grass on surface and globe temperatures in an urban area
D. Armsona, , , P. Stringerb, 1, , A.R. Ennosa, 2,
The process of urbanisation alters the thermal balance of an area resulting in an urban
heat island effect where cities can be several degrees centigrade warmer than the
surrounding rural landscape. This increased heat can make cities uncomfortable places
and, during heat waves, can pose serious health risks. This study looked at the role
that trees and grass can play in reducing regional and local temperatures in urban
areas during the summer within the urban landscape of Manchester, UK. In June and
July 2009 and 2010, we monitored the surface temperatures of small plots composed
of concrete and grass in the presence or absence of tree shading, and measured globe
temperatures above each of the surfaces. The same measures were also recorded at
mid-day on larger expanses of asphalt and grass in an urban park. Both surface and
shade greatly affected surface temperatures. Grass reduced maximum surface
temperatures by up to 24 °C, similar to model predictions, while tree shade reduced
them by up to 19 °C. In contrast, surface composition had little effect upon globe
temperatures, whereas shading reduced them by up to 5–7 °C. These results show that
both grass and trees can effectively cool surfaces and so can provide regional cooling,
helping reduce the urban heat island in hot weather. In contrast grass has little effect
upon local air or globe temperatures, so should have little effect on human comfort,
Liu, C. dan X. Li. 2012. Carbon storage and sequestration by urban forests in Shenyang, China.
Urban Forestry & Urban Greening, 11 (2): 121–128.
Urban forests can play an important role in mitigating the impacts of climate change by reducing
atmospheric carbon dioxide (CO2). Quantification of carbon (C) storage and sequestration by
urban forests is critical for the assessment of the actual and potential role of urban forests in
reducing atmospheric CO2. Liu dan Li (2012) study the quantification of C storage and
sequestration by urban forests in Shenyang, a heavily industrialized city in northeastern China.
The C storage and sequestration were estimated by biomass equations, using field survey data
and urban forests data derived from high resolution QuickBird images. The benefits of C storage
and sequestration were estimated by monetary values, as well as the role of urban forests on
offsetting C emissions from fossil fuel combustion.
The urban forests in areas within the third-ring road of Shenyang stored 337,000 t C (RMB92.02
million, or $ 13.88 million), with a C sequestration rate of 29,000 t/yr (RMB7.88 million, or $
1.19 million). The C stored by urban forests equaled to 3.02% of the annual C emissions from
fossil fuel combustion, and C sequestration could offset 0.26% of the annual C emissions in
Shenyang. In addition, our results indicated that the C storage and sequestration rate varied
among urban forest types with different species composition and age structure.
These results can be used to help assess the actual and potential role of urban forests in
reducing atmospheric CO2 in Shenyang. In addition, they provide insights for decision-makers
and the public to better understand the role of urban forests, and make better management
plans for urban forests.
. Urban Forestry & Urban Greening
Volume 9, Issue 4, 2010, Pages 323–332
Evaluating the potential for urban heat-island mitigation by greening parking lots
Akio Onishia, Xin Caob, , , , Takanori Itoc, Feng Shia, Hidefumi Imuraa
Artificial urban land uses such as commercial and residential buildings, roads, and
parking lots covered by impervious surfaces can contribute to the formation of urban
heat islands (UHIs), whereas vegetation such as trees, grass, and shrubs can mitigate
UHIs. Considering the increasing area of parking lots with little vegetation cover in
Nagoya, Japan, this study evaluated the potential for UHI mitigation of greening
parking lots in Nagoya. The relationships between land surface temperature (LST) and
land use/land cover (LULC) in different seasons were analyzed using multivariate linear
regression models. Potential UHI mitigation was then simulated for two scenarios: (1)
grass is planted on the surface of each parking lot with coverage from 10 to 100% at an
interval of 10% and (2) parking lots are covered by 30% trees and 70% grass. The
results show that different LULC types play different roles in different seasons and
times. On average, both scenarios slightly reduced the LST for the whole study area in
spring or summer. However, for an individual parking lot, the maximum LST decrease
was 7.26 °C in summer. This research can help us understand the roles of vegetation
cover and provide practical guidelines for planning parking lots to mitigate UHIs.
Peckham, S.C., P. N. Duinker, dan C. Ordóñez. 2013. Urban forest values in Canada: Views of
citizens in Calgary and Halifax. Urban Forestry and Urban Greening, 12 (2): 154–162.
A significant component of the urban ecosystem is the urban forest. It is also the
quintessential meeting point of culture and nature, so it is critical to incorporate
values-based approaches to managing them. The values that really count are those of
urban citizens. A novel qualitative method was used to determine what qualities of the
urban forest are valued by citizens of Calgary, Alberta, and Halifax, Nova Scotia,
Canada (Peckham, Duinker dan Ordóñez, 2013). These values were compared with
those reported in the literature to reveal that citizens value the urban forests mostly
for their non-material benefits. Specifically, urban forests contribute to human
emotional, intellectual, and moral fulfilment.
McPherson, E.G. dan J. R. Simpson. 2003. Potential energy savings in buildings by an urban tree
planting programme in California. Urban Forestry & Urban Greening, 2 (2): 73–86.
Tree canopy cover data from aerial photographs and building energy simulations were
applied to estimate energy savings from existing trees and new plantings in California
(McPherson dan Simpson, 2003). There are approximately 177.3 million energyconserving trees in California communities and 241.6 million empty planting sites.
Existing trees are projected to reduce annual air conditioning energy use by 2.5% with
a wholesale value of $ 485.8 million. Peak load reduction by existing trees saves
utilities 10% valued at approximately $778.5 million annually, or $ 4.39/tree. Planting
50 million trees to shade east and west walls of residential buildings is projected to
reduce cooling by 1.1% and peak load demand by 4.5% over a 15-year period. The
present wholesale value of annual cooling reductions for the 15-year period is $ 3.6
billion ($ 71/tree planted). Assuming total planting and stewardship costs of $ 2.5
billion ($ 50/tree), the cost of peak load reduction is $ 63/kW, considerably less than
the $ 150/kW benchmark for cost-effectiveness.
Soares, A.L., F.C. Rego, E.G. McPherson, J.R. Simpson, P.J. Peper, Q. Xiao. . 2011. Benefits and
costs of street trees in Lisbon, Portugal. . Urban Forestry & Urban Greening, 10 (2): 69–78.
It is well known that urban trees produce various types of benefits and costs. The
computer tool i-Tree STRATUM helps quantify tree structure and function, as well as
the value of some of these tree services in different municipalities. Soares, et al.
(2011) describes one of the first applications of STRATUM outside the U.S. Lisbon's
street trees are dominated by Celtis australis L., Tilia spp., and Jacaranda mimosifolia
D. Don, which together account for 40% of the 41,247 trees. These trees provide
services valued at $8.4 million annually, while $1.9 million is spent in their
maintenance. For every $1 invested in tree management, residents receive $4.48 in
benefits. The value of energy savings ($6.20/tree), CO2 reduction ($0.33/tree) and air
pollutant deposition ($5.40/tree) were comparable to several other U.S. cities. The
large values associated with stormwater runoff reduction ($47.80/tree) and increased
real estate value ($144.70/tree) were substantially greater than values obtained in U.S.
cities. Unique aspects of Lisbon's urban morphology and improvement programs are
partially responsible for these differences.
Seburanga, J.L., B.A. Kaplin, Q.-X. Zhang dan T. Gatesire. 2014. Amenity trees and green space
structure in urban settlements of Kigali, Rwanda. Urban Forestry & Urban Greening, 13 (1): 84–
93.
According to the national policy, overall forest and agroforestry cover in Rwanda is to increase
up to 30% land cover by 2020. On the other hand, demographic data reveal that Rwanda's urban
areas are among the fastest-growing on the continent. Seburanga et al. (2014) discussed
developments in Kigali's green spaces with regard to its rapid rate of expansion. The city green
space network consists of plant assemblages largely dominated by alien species (75%). Tree
cover fraction averaged at around 10–35%. No significant difference was observed between
field-drawn and photogrammetric-based fraction of tree cover estimates; making the later a
quick but cheap tool for rapid tree cover evaluation. Cultivated forests, urban woodlots and
domestic garden tree stands are far the most dominant types of green spaces in terms of
coverage of city surface area. Street tree communities and institutional gardens appear to be
the most intensively designed green space layouts. Both distribution and species composition in
domestic gardens were socioeconomic-driven. Palm trees were characteristic of fortunate
quarters while fruitbearing ornamental such as Psidium guajava and Persea americana were
common within scattered and informal settlements. Markhamia lutea, Erythina abyssinica,
Euphorbia candelabrum, Phoenix reclinata and Acacia sieberiana are among native taxa that
thrive to keep a place in the city. Euphorbia tirucalli, a native tree that is widespread in home
compound fences within informal settlements, is significantly declining as modern housing
expands and concrete-based fences replace live enclosures.
Livesley, S.J. , B. Baudinette dan D. Glover. 2014. Rainfall interception and stem flow by
eucalypt street trees – The impacts of canopy density and bark type. . Urban Forestry & Urban
Greening, 13 (1): 192–197.
Understanding how trees influence water movement in an urban landscape is important
because in an ‘engineered xeriscape’ small changes in rainfall frequency or magnitude have
significant implications to plant water availability and mortality at one extreme, and stormwater
runoff and flooding at the other. Livesley, Baudinette dan Glover (2014) relates direct
measures of tree canopy interception and discusses their implication for catchment hydrology in
different urban landscape contexts. The canopy throughfall and stemflow under two eucalypt
tree species in an urban street setting over a continuous five month period were measured.
Eucalyptus nicholii has a dense canopy and rough bark, whereas Eucalyptus saligna has a lessdense canopy and smooth bark. E. nicholii, with the greater plant area index, intercepted more
of the smaller rainfall events, such that 44% of annual rainfall was intercepted as compared to
29% for the less dense E. saligna canopy (2010). Stemflow was less in amount and frequency for
the rough barked E. nicholii as compared to the smooth barked E. saligna. However, annual
estimates of stemflow to the ground surface for even the smooth barked E. saligna would only
offset approximately 10 mm of the 200 mm intercepted by its canopy (2010).
Tree canopy and bark characteristics should be considered when planting in pervious green
space, or impervious streetscapes, because of their profound impact upon tree and surrounding
water availability, soil water recharge or runoff. This study provides an evidence base for tree
canopy impacts upon urban catchment hydrology, and suggests that rainfall and runoff
reductions of up to 20% are quite possible in impervious street scapes.
Pasher, J., M. Mcgovern, M. Khoury , dan J. Duffe. . 2014. Assessing carbon storage and
sequestration by Canada's urban forests using high resolution earth observation data. . Urban
Forestry & Urban Greening, Available online 16 May 2014.
Urban trees are important components of the landscape and offer numerous benefits; both
socio-economical and biophysical. Urban trees act as a sink for CO2, helping to offset carbon
emissions from urban areas by removing the greenhouse gas from the atmosphere through
photosynthesis. Pasher et al. (2014) develops estimates of Canada's greenhouse gas emissions
and removals which are submitted annually to the United Nations as part of ongoing
commitments under the United Nations Framework Convention for Climate Change. As part of
these reporting commitments countries are required to develop estimates of emissions and
removals of Greenhouse Gas that are the result of direct impact of human activities in the LandUse, Land-Use Change and Forestry Sector.
The approach which involves sampling high resolution aerial photographs was used to
determine urban tree coverage across Canada's major urban areas.
The Canadian urban areas have an estimated tree canopy cover of 27%. This tree cover is
estimated to store approximately 34,000 kt C and annually sequester approximately 2,500
kilotons of CO2. These estimates show significant improvement over previous methods used to
provide Canadian estimates.
Vailshery, L.S., M. Jaganmohan dan H. Nagendra. 2013. Effect of street trees on microclimate
and air pollution in a tropical city. Urban Forestry & Urban Greening, 12 (3): 408–415.
One of the fastest growing cities in India, Bangalore is facing challenges of urban
microclimate change and increasing levels of air pollution. Vailshery, Jaganmohan dan
Nagendra (2013) assessed the impact of street trees in mitigating these issues. At
twenty locations in the city, we compare segments of roads with and without trees,
assessing the relationship of environmental differences with the presence or absence
of street tree cover. Street segments with trees had on average lower temperature,
humidity and pollution, with afternoon ambient air temperatures lower by as much as
5.6 °C, road surface temperatures lower by as much as 27.5 °C, and SO2 levels reduced
by as much as 65%. Suspended Particulate Matter (SPM) levels were very high on
exposed roads, with 50% of the roads showing levels approaching twice the
permissible limits, while 80% of the street segments with trees had SPM levels within
prescribed limits. In an era of exacerbated urbanization and climate change, tropical
cities such as Bangalore will have to face some of the worst impacts including air
pollution and microclimatic alterations. The information generated in this study can
help appropriately assess the environmental benefits provided by urban trees,
providing useful inputs for urban planners.
Zhang, H., B. Chen, Z. Sun , dan Z. Bao. 2013. Landscape perception and recreation needs in
urban green space in Fuyang, Hangzhou, China. Urban Forestry & Urban Greening, 12 (1): 44–
52.
Zhang, Chen, Sun dan Bao (2013) analyzed the landscape characteristics and the
residents’ recreational activities in the urban green spaces in Fuyang, Hangzhou,
China. It explores the correlation of the desire to be in close proximity to urban green
space to engage in recreational activities (the need for recreation) related to residents’
demographic and socio-economic factors: gender, education, monthly income and
dwelling location. Residents’ preferences for landscape elements and attributes of
urban green space are examined using principal components analysis. In addition,
regression analysis identifies that coherence and vegetation are the most relevant
factors correlated with perceived overall recreational appropriateness of the three
most frequently visited urban parks.
This study attempted to quantify people's recreation needs in urban green space;
identify the landscape components in urban green space which can encourage more
outdoor visits and/or greater recreational activities; and provide proposals and
strategies on planning, management and conservation for recreation-oriented urban
green space which will enhance people's enjoyment and wellbeing by improving
landscape esthetic quality, recreational and ecological function.
Hardin, P.J. dan R. R. Jensen. 2007. The effect of urban leaf area on summertime urban surface
kinetic temperatures: A Terre Haute case study. Urban Forestry & Urban Greening, 6 (2): 63–72.
The urban heat island effect (UHIE) has been documented in many temperate region
cities. One cause of the UHIE is the replacement of green spaces with impervious
materials as urbanization commences and the city builds up and fills in. During the
summer, elevated urban temperatures result in increased electricity usage, higher
pollution levels, and greater resident discomfort. Through evapotranspiration and the
interception of solar radiation, increasing urban tree canopy cover can help mitigate
the UHIE. While this is universally accepted, the exact statistical relationship between
urban leaf area (as measured by leaf area index, LAI) and urban temperatures has not
been extensively studied. In a case study conducted in urban/suburban Terre Haute,
Indiana, USA, simple linear regression was employed to quantify the relationship
between in situ ceptometer LAI measurements and surface kinetic temperatures
(SKTs) measured using thermal satellite imagery acquired at 1100 local time (Hardin
dan Jensen, 2007) . For the 143 sample sites located in the study area, LAI accounted
for 62% of the variation in surface temperature. For every unit increase in LAI, surface
temperature decreased by 1.2 °C.
. Urban Forestry & Urban Greening, Volume 12, Issue 3, 2013, Pages 401–407
Estimating the stormwater attenuation benefits derived from planting four monoculture
species of deciduous trees on vacant and underutilized urban land parcels
M.C. Kirnbauera, , , B.W. Baetzb, , W.A. Kenneyc,
This paper presents research that was undertaken to determine whether planting deciduous
trees, using intensive tree planting schemes, on vacant and underutilized urban land provides
significant hydrologic benefits. This work contributes to an ongoing discussion on how to use
vacant and underutilized land productively, and may be important to land use decision-makers,
whose policies support the use of green infrastructure for stormwater management. Tree
growth parameters for four monoculture planting schemes were modeled (all trees had a
50.8 mm caliper at planting) and included (i) 450 Ginkgo biloba, (ii) 92 Platanus × acerifolia, (iii)
120 Acer saccharinum, and (iv) 434 Liquidambar styraciflua, on a 1.6-acre parcel. i-Tree Hydro
(formerly UFORE-Hydro) was used to derive a simplified Microsoft Excel-based water balance
model to quantify the canopy interception potential and evaporation, based on 7 years (2002–
2008) of historical hourly rainfall and mean temperature data in Hamilton, Ontario, Canada. This
study revealed that three of the species responded similarly, while one species (L. styraciflua)
performed significantly better with respect to total canopy storage potential and evaporation,
capturing and evaporating 2.9 m3/tree over the 7 years analyzed, or 1280 m3 for the total tree
stand of 434 trees. The analyses presented herein demonstrate that the tree canopy layer was
able to intercept and evaporate approximately 6.5%–11% of the total rainfall that falls onto the
crown across the 7 years studied, for the G. biloba, P. × acerifolia and A. saccharinum tree stands
and 17%–27% for the L. styraciflua tree stand. This study revealed that the rate at which a
species grows, the leaf area index of the species as it matures, and the total number of trees to
O’Donoghue, A. dan C.M. Shackleton. 2013. Current and potential carbon stocks of trees in
urban parking lots in towns of the Eastern Cape, South Africa. Urban Forestry & Urban Greening,
12 (4): 443–449.
Greening of shopping centre parking lots is a potentially important strategy that can contribute
to urban carbon mitigation efforts, improve aesthetics and the shopping experience of
consumers, whilst adding to urban biodiversity. O’Donoghue dan Shackleton (2013) studied
twenty-eight shopping centre parking lots in six Eastern Cape urban centres, South Africa, to
determine tree species composition, density and annual carbon sequestration potential. The
highest tree density was 66 trees ha−1, whereas the average density across all sampled parking
lots was less than half that (27.2 ± 22.6 trees ha−1). The average annual carbon sequestration
potential per parking lot was 1390 ± 2503 kg ha−1. Planting density was positively related to
annual sequestration rates, whilst parking lot age and the mean annual rainfall of the town had
no influence. Mean tree species richness per parking lot was 2.3 ± 1.8 species, with a positive
relationship to parking lot size, but not to mean annual rainfall of the site. The majority of trees
(62.5%) in parking lots were alien species, although newer parking lots had significantly greater
proportions of indigenous species. There was no difference in mean annual carbon
sequestration rate per tree between indigenous and alien trees species. Low tree densities and
small parking lot areas constrained the potential for earning carbon credits from trees in parking
lots.
Peper, P.J. dan E. G. McPherson . 2003. Evaluation of four methods for estimating leaf area of
isolated trees. . Urban Forestry and Urban Greening, 2 (1): 2003 19–29.
The accurate modeling of the physiological and functional processes of urban forests
requires information on the leaf area of urban tree species. Several non-destructive,
indirect leaf area sampling methods have shown good performance for homogenous
canopies. These methods have not been evaluated for use in urban settings where
trees are typically isolated and measurement may be complicated by proximity to
residential areas, buildings, signs, and other infrastructure elements.
Peper dan McPherson (2003) evaluated the accuracy, precision, efficiency and other
practical considerations associated with four methods of estimating the leaf area of
open-grown deciduous trees in urban forests. The methods included color digital
image processing (CD), the LAI-2000 Plant Canopy Analyzer, the CI-100 Digital Plant
Canopy Imager, and a logarithmic regression equation.
The CD method and LAI-2000 estimates showed good correlation with true leaf area
(R2 ≫ 0.71); however, only the CD method produced estimates within 25 percent of
mean true leaf area and met additional requirements for accuracy, precision, and
efficient use in urban settings.
McHale ,M.R., E. G. McPherson dan I.C. Burke. 2008. The potential of urban tree plantings to be
cost effective in carbon credit markets. Urban Forestry & Urban Greening, 6 (1): 49–60.
Emission trading is considered to be an economically sensitive method for reducing
the concentrations of greenhouse gases, particularly carbon dioxide, in the
atmosphere. There has been debate about the viability of using urban tree plantings in
these markets. The main concern is whether or not urban planting projects can be cost
effective options for investors. McHale , McPherson dan Burke (2008) compared the
cost efficiency of four case studies located in Colorado, and used a model sensitivity
analysis to determine what variables most influence cost effectiveness. Some urban
tree planting projects in specific locations may be cost effective investments. The
carbon assimilation rate, which is mainly a function of growing season length, has the
largest influence on cost effectiveness, however resource managers can create more
effective projects by minimizing costs, planting large-stature trees, and manipulating a
host of other variables that affect energy usage.
Stabler,L.B., C. A. Martin, dan A. J. Brazel. 2005. Microclimates in a desert city were related to
land use and vegetation index. Urban Forestry and Urban Greening, 3 (3–4): 137–147.
A heterogeneous patchwork mosaic of soil, vegetation, and built surfaces that result
from a variety of urban land uses cause urban microclimates within cities. Stabler,
Martin dan Brazel (2005) studied the seasonal relationships of land use, urban plant
cover and microclimate in Phoenix, Arizona, USA, metropolitan. Land use had the most
pronounced effect on microclimate during the early morning hours of summer.
Agricultural and residential land uses had the highest relative humidities, dew point
temperatures, and NDVI (normalized differential vegetation index ), and the lowest air
temperatures. Commercial and industrial land uses had highest temperatures and
lowest NDVI. Temperatures were generally negatively correlated to NDVI, while
humidity and dew point temperatures were generally positively correlated to NDVI.
Distance from the urban core did not affect NDVI but had a significant negative effect
on adjusted air temperature.
The microclimates in this desert city are caused by variations in plant cover, and an
interactive effect of vegetation density and other non-vegetative urban surfaces.
McPherson ,E.G. dan J. R. Simpson. 2002. A comparison of municipal forest benefits and costs in
Modesto and Santa Monica, California, USA. Urban Forestry and Urban Greening, 1 (2): 61–74.
McPherson dan Simpson (2002) analyze a comparison of the structure, function, and
value of street and park tree populations in two California cities. Trees provided net
annual benefits valued at $2.2 million in Modesto and $805,732 in Santa Monica.
Benefit-cost ratios were 1.85:1 and 1.52:1 in Modesto and Santa Monica, respectively.
Residents received $1.85 and $1.52 in annual benefits for every $1 invested in
management.
Aesthetic and other benefits accounted for 50% to 80% of total annual benefits, while
expenditures for pruning accounted for about 50% of total annual costs. Although
these results were similar, benefits and costs were distributed quite differently in each
city.
Variations in tree sizes and growth rates, foliation characteristics, prices, residential
property values, and climate were chiefly responsible for different benefits and costs
calculated on a per tree basis.
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