Biotic homogenization of China’s urban greening: A meta-analysis on woody species

Human preferences for the species in urban greening have greatly facilitated the spread of non-native species, resulting in the homogenization of urban plant communities across spatial scales. We selected 11 major cities along the Yangtze River in China and examined the species composition in their urban plant communities. We found that China’s urban plant communities are becoming homogenized, as urban communities of different cities are highly similar to each other despite the geographical separation. Meanwhile, these artificial communities we investigated have diverged greatly from the natural communities at both the city and the geographic scale. We recorded a total of 91 woody species that have been used in urban greening in all 11 cities. Of those species, 27% were cultivars and introduced species, and 25% were being used outside of their native distribution ranges in China. This may be explained by the market and urban planners who tend to favor greening plants that are highly profitable and have aesthetic ornamental traits, rather than spending time introducing and acclimatizing the native species in each city. Given the current trend of homogenization, measures that recognize the importance of native species should be emphasized with comprehensive urban planning strategies.     

Assessment and optimization of green space for urban transformation in resources-based city – A case study of Lengshuijiang city,China

Urbanization in China has changed gradually from production-oriented to consumption-oriented in recent years. Comfort and accessibility of green infrastructures effect the rate of urbanization and transformation. A well designed urban green space system is an essential part of the urbanization process. In this paper, the urban green space of Lengshuijiang city was assessed both qualitatively and quantitatively using data of field survey and high resolution remote sensing. In the study area, green space coverage was 37.14%, green space percentage was 33.45% and per capita park green space was 16.25 m². The high green space coverage suggested that there were ample potentials for further urban transformation. Within a 30 min service radius of existing green space, total service area was 204.49 ha, which accounted for 16.26% of the study area. A high proportion of the green space was made up of urban parks which were unevenly distributed across the study area. A green space optimization strategy, aimed at improving green space quality and accessibility, was proposed. After optimization, total service areas within the 30 min service radius will increase to 492 ha (39.12%), an increase of 22.86%. Our study demonstrated that combining qualitative and quantitative methods is an effective and reliable way for green space assessment and reliable and can be used for urban green space planning and management for small resource-based cities like Lengshuijiang in its process of urban transformation.     

Influences on the use of urban green space – A case study in Odense,Denmark

Increasing the use of urban green space has appeared on the political agenda, primarily because increased use is expected to improve the health and well-being of the urban population. Green space is contributing to restoring mental fatigue, serving as a resource for physical activity, reducing mortality and reducing the level of stress.However, knowledge and experience on how to implement this agenda are scarce. In this paper, we use a socio-ecological model as framework when studying influences on the use of respondents’ nearest urban green space in the Danish city of Odense. Data were obtained from a survey sent to 2500 randomly selected adult residents within the central part of the city. We tested the relative importance of different factors on the frequency of use of the nearest urban green space by using a multivariate logistic regression model. The results show that almost half of the respondents did not use their nearest green space the most. Whether or not respondent used their nearest green space most depends primarily on area size, distance to the area and factors that are likely to express a reduced mobility; old age, young children and poor health.If the nearest urban green space also is the most used green space, having a dog is the only factor that significantly increases the frequency of use. Further research is needed to determine what it is that makes people use an area more, if the basic conditions of a reasonable size (>5 ha) within a reasonable distance (<600 m) are fulfilled.     

Mapping of urban roadside trees – A case study in the tree register update process in Helsinki City

This case study describes a method for utilizing leaf-off airborne laser scanning (ALS) data for mapping characteristics of urban trees. ALS data were utilized to detect and update all street trees in the tree inventory of the City of Helsinki, Finland. The inventory consists of roughly 20,000 street trees with mean diameter at breast height (DBH) of 24 cm and mean height of 10.6 m. The large number of trees makes the manual updating process very laborious. The automatic mapping procedure presented in this paper detected 88.8% of all trees in the inventory. Tree height was predicted with root mean square error (RMSE) of 1.27 meters and tree DBH with RMSE of 6.9 cm. The presented method provides a practical and cost–effective tool for the mapping of urban tree characteristics. The cost–efficiency was further enhanced because the used ALS data were originally collected for other urban planning purposes.     

Synergy of urban green space planning and ecosystem services provision: A longitudinal exploration of China’s development

Ecosystem services (ES) concepts and approaches have become more appealing to practice, such as municipal/urban planning, environmental policies and governance to address sustainable development. Inclusion of this concept in the planning or policy discourses is the first step for further implementation on the ground. Using China’s capital, Beijing, as the case study, this article analyzes how ES (or similar concepts) have permeated China’s urban development history since 1949 when the New China was established and how this has to be with China’s urban green space development. The results show: (1) There were no explicit references to “ecosystem services” per se, but overlapping concepts such as “functions”, “values” and “benefits” can be found in planning documents and, importantly, the lack of the concept per se has not affected the detailed services that emerged in all plans. (2) Among the three ES sections, only cultural services run from the beginning to end although the included services kept changing. Other sections show considerable variation and less continuity – the focal services of each stage changed over time. (3) Through the ES lens, some general patterns regarding China’s urban development can be found such as regulation services gradually become valued for their own sake. The patterns found in Chinese planning documents are then compared with some western regions. This study reveals limitations of the past and opportunities for the future to inform urban development decision-making. Adaptation of old and incorporating new ES concepts can improve the quality of plans and foster cities’ ability to learn from past patterns for future sustainability.     

Humanization of nature: Testing the influences of urban park characteristics and psychological factors on collegers’ perceived restoration

Previous studies have mainly focused on the independent role of landscape characteristics or preference on psychological restoration respectively. However, few studies have explored the complex relationships between restorative effects, landscape characteristics, preference and place bonding factors, particularly in urban parks. The development of new data environment and technique methods enables such a synthesis of innovative approach to reveal the influences of urban park characteristics and various psychological factors on collegers’ perceived restoration. A typical urban park in Wuhan, China, was selected for pilot study, in which 1560 crowdsourced images were collected using the Public Participation Geographic Information System (PPGIS) tool. With the help of Deep Learning techniques, landscape characteristics were combined with perceptual factors for the Partial Least Squares (PLS) based statistical analysis. It was found that some landscape properties, such as vegetation and water, presented indirect impacts in activating restoration via psychological mediators. The mediating effect of sense of place and the moderating effects of landscape characteristics on the preference-restoration nexus were revealed. These findings shed new light on the complex process in environmental restoration in which psychological and physical factors are intertwined. At the end, theoretical and managerial implications were proposed for the improvement of landscape planning in restoration studies.     

How China’s linked urban–rural construction land policy impacts rural landscape patterns: a simulation study in Tianjin,China

Context

To prevent the area of arable land from crossing the limit of 120 million ha arable land red line, China’s government proposed a linked urban–rural construction land policy. This policy helps to protect the arable land but will impact the rural landscape.

Objective

The objective is to evaluate the effect of the linked urban–rural construction land policy on rural landscape in the future.

Methods

We performed a simulation method to predict the rural landscape pattern changes in Tianjin during 2005–2020 using a cellular automata and multi-agent system model under the scenarios with or without implementing this policy. The landscape metrics were calculated for both scenarios to find the effects caused by this policy.

Results

Following this policy, the Total Area and Large Patch Index of arable land decreased slowly. 65.50% of the occupied arable land can be compensated. For rural settlements, the Mean Patch Area increased to 2.87 times that in 2005. Number of Patches reduced greatly, and 1053 of the total rural settlements distributed along the periphery of Tianjin were reclaimed for arable land during 2005–2020. Aggregation Index increased greatly.

Conclusions

According to the simulation model, the policy is effective on slowing down the loss of total arable land and the process of large arable land fragmentation. The increasing degree of aggregation of rural settlements is beneficial to the optimal allocation of resources and rural centralized management. However, as the rural settlements gather to urban construction land, they are more vulnerable to urban issues.

     

The utility of ancient forest indicator species in urban environments: A case study from Poznań, Poland

We aimed to assess the impact of land-use structure on AFIS occurrence and evaluation of these bioindicators in urban conditions. We compiled data about forest continuity based on archival maps and forest management plans; floristic records of 79 AFIS occurrences were collected within a 1 × 1 km grid and land-use form structure in Poznań (W Poland). We tested fidelity of AFIS using χ² tests and effects of land-use structure using random forest models. We also checked spatial autocorrelation and its impact on AFIS distribution patterns within old and recent forests, using spatially explicit generalized linear models. We found a strong relationship between AFIS number per grid square and fraction of forests and waters in land-use structure. Relationships between AFIS distribution and land-use shows that AFIS are a good proxy describing human impact or an urbanity gradient. AFIS number per grid square shows small, but significant positive spatial autocorrelation, which suggests possibilities of migration into new forests. AFIS, treated as a bioindicative group of species, may be a useful indicator of landscape and land-use structure transformation in urban environments. Occurrence of many AFIS that are endangered at the city scale indicates the need for conservation of old forests in urban areas, to preserve biodiversity in urban environments. Thus, AFIS may act as indicators of old forests with high conservation value in cities, which need special protection.     

How does enclosed private residential green space impact accessibility equity in urban regions? A case study in Shenzhen,China

Compared with public parks, residential quarter green space (RQGS) is a type of enclosed private green space that is located in residential areas and has higher visit frequency. Generally, in China residential areas with high housing prices have higher quality and more quantity of RQGS. Therefore, the differences in RQGS between residents with different socio-economic status may influence the equity of urban green space accessibility. However, due to the lack of data sources, few existing studies have taken RQGS into account as a part of urban green space supply resources. Based on multi-source geographic big data, this paper takes Shenzhen as the research area to explore the impact of RQGS on the spatial pattern and fair distribution of green space accessibility. The total green space accessibility (TGSA), which includes the accessibility of RQGS, and the public park accessibility (PPA) were calculated using the Gaussian-based two-step floating catchment area method (2SFCA). Using housing prices to indicate the income level of dwellers, bivariate Moran’s I and multiple regression were adopted to explore equity of urban green space accessibility. The main conclusions were: (1) The accessibility of green space increased by 27.97% on average after considering RQGS and ignoring RQGS could underestimate the accessibility of green space, particularly in the residential quarter with high housing prices near the city center. (2) The regression coefficients of housing prices with PPA and TGSA were 0.042 (p < 0.01) and 0.160 (p < 0.001), respectively, indicating that the advantages of high-income groups in RQGS may further exacerbate the inequity of urban green space accessibility. The research conclusions may provide a scientific basis for optimizing the spatial structure of green space in urban areas and ensuring the equitable distribution of green space.     

Thailand’s catastrophic flood: Bangkok tree mortality as a function of taxa,habitat, and tree size

Urban areas have unique environments such as high air temperature, soil compaction and disturbance, and air and water pollution often impose plant stresses. Natural disasters can impose even greater stresses on plants in such areas. In 2011 Bangkok, Thailand experienced its worst flooding in over two decades, inundated up to a meter for a month. Here we report on tree tolerance to submerged, anoxic soils based on mortality. We identified over 6500 trees by taxa: 395 species in 219 genera within 60 families, which were categorized into three groups: susceptible (>50% mortality), tolerant (<50% mortality), and highly tolerant (no mortality). Among all the species, 18% were categorized as flood susceptible, 75% as tolerant, and 7% as highly tolerant. The floods resulted in decreased overall species richness by 18%, particularly in the Magnoliaceae and Lauraceae families, for which the mortality was 100% and 66%, respectively. Flood susceptible species were mostly from high rainfall habitats such as the hill evergreen forest. As expected, highly flood tolerant species were from the mangrove forests, beach/strand forests, and swamp plant communities, where the root zones are persistently saturated with lower quality water. Unexpectedly, many species native to higher temperature, drier, often deciduous lowland habitats were found to be flood tolerant, and were from the cultivated fruit and ornamental species. The results also indicated that smaller and younger trees suffered more mortality than larger and more mature trees. Therefore, during the tree selection process for planting in urban environments that may be at risk of frequent flooding, species from a wide spectrum of ecological habitats should be considered; particularly those characterized by one or more environmental stresses, such as drought, salt, heat, or saturated soils.     

The effect of summer pruning and nitrogen on growth,cropping and storage quality of Cox’s Orange Pippin apple

Pruning in late summer was compared with winter pruning on mature 23-year-old spur pruned trees of Cox’s Orange Pippin on M.2 rootstock. Two nitrogen treatments were superimposed, namely a standard dressing of 126 units N (sulphate of ammonia) applied in March as compared with 288 units N (nitrate of soda) applied in mid-August at the time of summer pruning. Summer pruning reduced trunk girth increment, advanced blossom development, increased the amount of red colour on the fruits and drastically reduced the incidence of bitter pit in stored fruit. The treatments did not affect cropping. Nitrogen treatments had no overall effect upon the incidence of bitter pit, but in the first season, when bitter pit was most prevalent, high levels of N applied in August reduced the amount, a similar trend being recorded the following year.     

Tree mapping using airborne,terrestrial and mobile laser scanning – A case study in a heterogeneous urban forest

We evaluated the accuracy and efficiency of airborne (ALS), terrestrial (TLS) and mobile laser-scanning (MLS) methods that can be utilized in urban tree mapping and monitoring. In the field, 438 urban trees located in park and forested environments were measured and mapped from our study area located in Seurasaari, Helsinki, Finland. A field reference was collected, using a tree map created manually from TLS data. The tree detection rate and location accuracy were evaluated, using automatic or semiautomatic ALS individual tree detection (ALS_ITDauto or ALS_ITDvisual) and manual or automatic measurements of TLS and MLS (TLS_auto, MLS_auto, MLS_manual, MLS_semi). Our results showed that the best methods for tree detection were TLS_auto and MLS_manual, which detected 73.29% and 79.22% of the reference trees, respectively. The location accuracies (RMSE) varied between 0.44 m and 1.57 m; the methods listed from the most accurate to most inaccurate were MLS_semi, TLS_auto, MLS_manual, MLS_auto, ALS_ITDauto and ALS_ITDvisual. We conclude that the accuracies of TLS and ALS were applicable for operational urban tree mapping in heterogeneous park forests. MLS_manual shows high potential but manual measurements are not feasible in operational tree mapping. Challenges that should be solved in further studies include ALS_ITDauto oversegmentation as well as MLS_auto processing methodologies and data collection for tree detection.     

Peoples’ use of,and concerns about,green space networks: A case study of Birchwood,Warrington New Town,UK

Cultural services provided by green space networks and in particular leisure and recreational opportunities are central to the quality of life of those living in urban areas. However, the literature concerned with green space networks has mainly focused on planning aspects rather than on recreational use. The aim of this study was to evaluate the recreational use of, and concerns about, a naturalistic green space network. The case study location was the naturalistic woodland framework in Birchwood, Warrington, UK, known as Birchwood Forest Park. Non-participant observation and content analysis of local archives were used to collect quantitative and qualitative data. Birchwood Forest Park was used more for leisure activities (52.8%, N=1825; i.e. recreation, sports or play) than for utilitarian purposes (47.2%, N=1825; i.e. as walking or cycling thoroughfare). However, utilitarian walking (30%, N=1825) was the most frequent type of activity observed. The maintenance of the naturalistic woodland framework was the most frequent concern mentioned in the local archives (33.3%, N=234). This case study suggests that the recreational patterns in, as well as peoples' concerns about, naturalistic urban landscapes may be a factor of high-quality maintenance and associated local aesthetic and cultural perceptions. In developing, planning or managing comprehensive urban green space networks it is important to ensure that natural looking scenes are well maintained and that the local community is culturally connected to such scenes.     

A new pest in vineyard under grass management model: study on the biological characteristics and control of Smaragdina nigrifrons北大核心CSCD

【Objective】For many years, our team have been working on organic cultivation management and pest control of wine grapes. Ground cover management model has been a new green management model currently implemented in the northern orchards. However, under the grass-covering system, new or secondary pests and diseases may increase in the orchards if the pasture type and planting and management models are not carefully chosen. These pests and diseases might become a new problem in fruit production. For example, a serious insect pest of wine grapes, Smaragdina nigrifrons (Hope) (Coleoptera: Eumolpidae) was found in the vineyard in Changli, China for the first time. This pest is highly harmful and occurs continuously in grass-covered orchards. In order to understand the occurrence and damage of the pest, the authors conducted field and lab investigations for three consecutive years. Its morphological characteristics were described, and its living habits, damage, and occurring pattern were observed, and the control methods were suggested.【Methods】Systematic field investigation was combined with indoor feeding and observation. Morphological characteristics of the beetles were observed under Primo Star microscope, and their taxonomic status was determined. The population dynamics and occurrence pattern were monitored by yellow cards trapping technique. 【Results】 The results showed that the adult of S. nigrifrons was long ovate. Female adults were 4.5 to 5.9 mm in length and 2.2 to 3.0 mm in width; males were 4.0 to 5.6 mm in length and 1.9 to 2.6 mm in width. Their head was black, the top was highly convex, and the leading edge had a wavy fold. There was no obvious boundary between the lip base and the forehead, which was slightly raised with numerous deep points. The tentacles were short and thin. The basal 4 knots of the tentacle were yellowish brown, the other sections were brown or black, and the sections after the 5th section were jagged. The chest was red brown or yellow brown. The scutellum and the elytra were yellow brown or red brown, and the elytra had wide black transverse band. Male's abdomen penultimate web was raised and female’s was sag. The adults of S. nigrifrons do damage on the tender new leaves. They had pseudo- lethality, coming out during the day and hiding at night. Generally it damaged tender leaves on the top of the canopy, with irregular notches in the injured leaves. The damage rate of local wine grape reached 100%. The adults usually appeared in July and August and might have one generation a year. They were active during 8:00 to 11:00 and 15:00 to 18:00. They had no phototaxis but had feigned death. In addition to harming the top leaves of wine grape trees, they also harmed the inter-row weeds, and the damage in the grass growing area was significantly more serious than in the weeding area. 【Conclusion】It is speculated that the occurrence and harm of S. nigrifrons in the wine grape vine of Changli Langes Winery is closely related to the implementation of the new orchard management mode with grass cover, indicating that it has potential risk. Therefore, it is extremely important to carry out a risk assessment analysis of S. nigrifrons. The occurrence and damage of S. nigrifrons in other fruit orchards in the north, especially in slopes, semi-mountainous areas and mountainous areas, needs further investigation. © 2019 Journal of Fruit Science     

Influences of buildings on urban heat island based on 3D landscape metrics: an investigation of China’s 30 megacities at micro grid-cell scale and macro city scale

Landscape Ecology - The building landscape greatly affects the urban heat island (UHI), especially in three-dimensional (3D) space, by changing the energy flow between the land surface, the...     

Temporal variation of characteristic scales in urban landscapes: an insight into the evolving internal structures of China’s two largest cities

Urbanization has induced profound landscape changes. While the spatiotemporal patterns of urban landscapes have been extensively studied, the manner by which the internal structures of already urbanized areas change remains little understood. Characteristic scales are an important measure of landscape structure, and they represent the typical spatial extents of landscape elements in hierarchies. In this study, we quantified temporal variations of the characteristic scales in the central urban landscapes of Beijing and Shanghai over an 18?year period. Using transect data from Landsat images, characteristic scales were identified through wavelet analysis and then classified into several discrete domains using the k-means clustering method. These characteristic scale domains appeared to correspond with the typical extents of the blocks and block clusters in the study areas. Results showed that the number of the characteristic scale domains changed within a small range of 3?C5 while the mean values of the characteristic scales within the domains showed substantial temporal variation. Larger characteristic scales were more variable than smaller ones in both cities. Distinguishing relative change rates of building forms, land use and street layout of urban landscapes allowed us to interpret these differences. The street layout of urban landscapes usually reacts slowly to the force of change, acting as the skeleton of the urban landscape. As a result, block sizes can remain relatively stable and corresponding characteristic scales present inheritance features. Land use and building forms are more susceptible to changes. Block clusters with flexible extents could result in significant variation of characteristic scales.     

Greenspace and wellbeing in Tehran: A relationship conditional on a neighbourhood’s crime rate?

Greenspace is widely regarded as supportive of wellbeing. One mechanism through which this relationship is reasoned to function is through psychological and physiological restoration. This study maintains that the link between greenspace and wellbeing depends on the crime rate in the neighbourhood. This is investigated by employing data from the Urban Health Equity Assessment and Response Tool-2 (Urban HEART-2) survey linked to Geographic Information Systems data. The results of spatial error model, estimated by Generalised Method of Moments estimation, reveal that greenspace is positively linked to wellbeing and that the crime rate is negatively linked to wellbeing. The findings also reaffirm earlier evidence indicating that link between greenspace and wellbeing is conditional on the crime rate in an individual’s local area. Moreover, the results also indicate that this dependency is not experienced in a more pronounced way for females. The findings of this study point to the need for policy makers and planners who wish to promote the wellbeing of their citizens to address neighbourhood crime rates.     

Healing gardens in children’s hospitals: Reflections on benefits,preferences and design from visitors’ books

There is increasing interest in the use of healing gardens in healthcare settings to provide therapeutic benefits. However it is not yet well understood how people who spend time in these gardens use these spaces, and whether the intended benefits are experienced. This paper evaluates visitor feedback about healing gardens at the Lady Cilento Children’s Hospital in Brisbane, Australia, to gain insight into end-user experiences compared with existing literature about experiences of healing gardens and natural contexts. We have coded and analysed unsolicited comments left in visitors’ books over a period of four weeks immediately after the hospital was opened. Several themes have been identified relating to reasons for which people access the healing gardens; benefits they perceive from spending time in these spaces; and features and aspects of the gardens that are most appreciated. We conclude that the gardens at the Lady Cilento Children’s Hospital provide emotional respite to visitors, through appreciation of the views, being able to have time out, being in nature, restorative experiences, and access to outdoor air. The visitor feedback suggests that the original intention of the garden design has been largely successful, and provides insight into particular aspects of the garden design that are critical to enhancing visitor benefits.