scholarly journals Problems and Management of Acacia-Dominated Urban Forests on Man-Made Slopes in a Subtropical, High-Density City

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 323
Author(s):  
Cody H. Y. Lee ◽  
Alvin M. C. Tang ◽  
Derrick Y. F. Lai ◽  
Amos P. K. Tai ◽  
Alan S. L. Leung ◽  
...  
Keyword(s):  
Hong Kong ◽  
Ecosystem Services ◽  
High Risk ◽  
Native Species ◽  
Urban Forests ◽  
Arrested Succession ◽  
Native Forests ◽  
Soil Constraints ◽  
Exotic Tree ◽  
The 1960S

Acacia spp. are exotic tree species that have been widely planted on man-made slopes in Hong Kong since the 1960s. However, as they become mature and senescent, they may become a concern and cause various problems, including soil constraints for plant growth, decreasing provision of intended ecosystem services, declining syndromes, arrested succession, and high risk of failure. In this perspective paper, we present and discuss these problems using practical examples of Acacia-dominated urban forests on man-made roadside slopes in Hong Kong, based on a cross-disciplinary survey and a literature review. To conclude, we suggest that selective cutting, specific silvicultural operations of Acacia plantations, and the management of plantation edge and soils can be exercised, along with the planting of native species, to potentially alleviate these problems associated with mature Acacia plantations, by promoting the establishment of native forests, enhancing biodiversity, expediting succession, and providing better ecosystem services.

scholarly journals Beijing Resident’s Preferences of Ecosystem Services of Urban Forests

Forests ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 14
Author(s):  
Han Zhi-Ying ◽  
Youn Yeo-Chang
Keyword(s):  
Ecosystem Services ◽  
Air Quality ◽  
Fresh Water ◽  
Urban Forest ◽  
Urban Forestry ◽  
Urban Forests ◽  
Wildlife Habitat ◽  
Quality Regulation ◽  
Water Provision ◽  
Air Quality Regulation

This paper aims to investigate the Beijing resident’s preferences over various options of urban forest management strategies. The literature investigation and expert Delphi method were conducted to classify the ecosystem services of urban forests into six categories: (1) fresh water provision, (2) noise reduction, (3) moderation of extreme events, (4) air quality regulation, (5) species diversity and wildlife habitat, and (6) recreation and spiritual experience. To elicit the relative preferences to ecosystem service (hereafter referred to as ES) of Beijing residents, we employed the choice experiment method. The data were collected by interviews with questionnaires conducted in October 2017, and a total of 483 valid questionnaires were analyzed. The subjects of this experiment were residents older than 19 years old who have lived in Beijing for more than 1 year and have visited any one of the urban forests located in Beijing more than once during 2016. The results were as follows: Firstly, the air quality regulation ES was considered as the most important service for Beijing residents in terms of their choices of urban forest. In addition, Beijing residents regarded the fresh water provision ES as the second most important ES. Beijing residents were willing to pay up to 1.84% of the average monthly income of Chinese households annually to expand urban forest ecosystems in order to improve air quality. Secondly, apartment owners were willing to pay more municipality tax for forest ESs than residents who did not own an apartment. Thirdly, residents were more willing to pay for urban forest ESs as their income increases. The results indicated that Beijing residents were willing to pay more tax in support of urban forestry for air quality improvement. This research suggests that urban environmental policy makers in Beijing should pay more attention to the regulation function of forests (especially improving air quality) when designing and managing urban forests.

scholarly journals Spatial Pattern Analysis of the Ecosystem Services in the Guangdong-Hong Kong-Macao Greater Bay Area Using Sentinel-1 and Sentinel-2 Imagery Based on Deep Learning Method

2021 ◽  
Vol 13 (13) ◽  
pp. 7044
Author(s):  
Dawei Wen ◽  
Song Ma ◽  
Anlu Zhang ◽  
Xinli Ke
Keyword(s):  
Hong Kong ◽  
Deep Learning ◽  
Ecosystem Services ◽  
Land Cover ◽  
Spatial Pattern ◽  
Sustainable Urban Development ◽  
Spatial Pattern Analysis ◽  
Bay Area ◽  
Urban Rural ◽  
Sentinel 2

Assessment of ecosystem services supply, demand, and budgets can help to achieve sustainable urban development. The Guangdong-Hong Kong-Macao Greater Bay Area, as one of the most developed megacities in China, sets up a goal of high-quality development while fostering ecosystem services. Therefore, assessing the ecosystem services in this study area is very important to guide further development. However, the spatial pattern of ecosystem services, especially at local scales, is not well understood. Using the available 2017 land cover product, Sentinel-1 SAR and Sentinel-2 optical images, a deep learning land cover mapping framework integrating deep change vector analysis and the ResUnet model was proposed. Based on the produced 10 m land cover map for the year 2020, recent spatial patterns of the ecosystem services at different scales (i.e., the GBA, 11 cities, urban–rural gradient, and pixel) were analyzed. The results showed that: (1) Forest was the primary land cover in Guangzhou, Huizhou, Shenzhen, Zhuhai, Jiangmen, Zhaoqing, and Hong Kong, and an impervious surface was the main land cover in the other four cities. (2) Although ecosystem services in the GBA were sufficient to meet their demand, there was undersupply for all the three general services in Macao and for the provision services in Zhongshan, Dongguan, Shenzhen, and Foshan. (3) Along the urban–rural gradient in the GBA, supply and demand capacity showed an increasing and decreasing trend, respectively. As for the city-level analysis, Huizhou and Zhuhai showed a fluctuation pattern while Jiangmen, Zhaoqing, and Hong Kong presented a decreasing pattern along the gradient. (4) Inclusion of neighborhood landscape led to increased demand scores in a small proportion of impervious areas and oversupply for a very large percent of bare land.

scholarly journals Ecosystem Services Changes on Farmland in Response to Urbanization in the Guangdong–Hong Kong–Macao Greater Bay Area of China

Land ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 501
Author(s):  
Xuege Wang ◽  
Fengqin Yan ◽  
Yinwei Zeng ◽  
Ming Chen ◽  
Bin He ◽  
...  
Keyword(s):  
Land Use ◽  
Hong Kong ◽  
Ecosystem Services ◽  
Ecosystem Service ◽  
Food Production ◽  
Great Loss ◽  
The Past ◽  
Bay Area ◽  
Farmland Loss ◽  
The World

Extensive urbanization around the world has caused a great loss of farmland, which significantly impacts the ecosystem services provided by farmland. This study investigated the farmland loss due to urbanization in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) of China from 1980 to 2018 based on multiperiod datasets from the Land Use and Land Cover of China databases. Then, we calculated ecosystem service values (ESVs) of farmland using valuation methods to estimate the ecosystem service variations caused by urbanization in the study area. The results showed that 3711.3 km2 of farmland disappeared because of urbanization, and paddy fields suffered much higher losses than dry farmland. Most of the farmland was converted to urban residential land from 1980 to 2018. In the past 38 years, the ESV of farmland decreased by 5036.7 million yuan due to urbanization, with the highest loss of 2177.5 million yuan from 2000–2010. The hydrological regulation, food production and gas regulation of farmland decreased the most due to urbanization. The top five cities that had the largest total ESV loss of farmland caused by urbanization were Guangzhou, Dongguan, Foshan, Shenzhen and Huizhou. This study revealed that urbanization has increasingly become the dominant reason for farmland loss in the GBA. Our study suggests that governments should increase the construction of ecological cities and attractive countryside to protect farmland and improve the regional ESV.

scholarly journals The Biodiversity of Urban and Peri-Urban Forests and the Diverse Ecosystem Services They Provide as Socio-Ecological Systems

Forests ◽  
2016 ◽  
Vol 7 (12) ◽  
pp. 291 ◽  
Author(s):  
Stephen Livesley ◽  
Francisco Escobedo ◽  
Justin Morgenroth
Keyword(s):  
Ecosystem Services ◽  
Urban Forests ◽  
Ecological Systems

A global review of arthropod-mediated ecosystem-services in Vaccinium berry agroecosystems

2014 ◽  
Vol 7 (1) ◽  
pp. 41-78 ◽  
Author(s):  
Matthew S. Jones ◽  
Henri Vanhanen ◽  
Rainer Peltola ◽  
Frank Drummond
Keyword(s):  
Ecosystem Services ◽  
Native Species ◽  
Evolutionary History ◽  
Insect Pest ◽  
Agricultural Pests ◽  
Fruit Crops ◽  
Beneficial Arthropods ◽  
Pollination Services ◽  
Arthropod Fauna ◽  
Production Practices

Native beneficial arthropods, including bees, predators, and parasitoids, provide valuable ecosystem services, which help to maintain agricultural productivity and reduce the need for pesticide inputs.Vacciniumberry species are somewhat unique compared to many of the world’s fruit crops in that, up until recently, most of the harvesting and culture of species for food occurred in the geographic regions of their origin. This suggests that insects involved in many of the ecosystem services for these berries are native species that have a shared co-evolutionary history. Due to the shared phylogenetic origins of theVacciniumspp. agroecosystems, the shared need for efficient pollination, and a number of shared agricultural pests, the potential exists for research from these related systems to closely apply to agroecosystems within the same genus. This review brings together research regarding arthropod-mediated ecosystem services from a number of prominentVacciniumagroecosystems worldwide. In total, thirty-nine ecosystem service studies are discussed. These studies quantified arthropod-mediated ecosystem services being provisioned toVacciniumagroecosystems. Additionally, thirty-nine surveys of arthropods closely associated and/or providing ecosystem services toVacciniumsystems are also reviewed. Studies took place almost exclusively in temperate regions with a heavy emphasis on insect pest biological control and pollination services. It is our hope that by synthesizing this body of literature, researchers and growers might be able to utilize research methods, results, and conservation recommendations despite differences in production practices and local arthropod fauna.

scholarly journals Exotic urban trees conserve similar natural enemy communities to native congeners but have fewer pests

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6531 ◽  
Author(s):  
Steven D. Frank ◽  
Kristi M. Backe ◽  
Casey McDaniel ◽  
Matthew Green ◽  
Sarah Widney ◽  
...  
Keyword(s):  
Natural Enemies ◽  
Tree Species ◽  
Native Species ◽  
Urban Trees ◽  
Scale Insects ◽  
Single Family ◽  
Exotic Trees ◽  
Exotic Tree ◽  
Native Tree Species ◽  
Arthropod Pest

Urban trees serve a critical conservation function by supporting arthropod and vertebrate communities but are often subject to arthropod pest infestations. Native trees are thought to support richer arthropod communities than exotic trees but may also be more susceptible to herbivorous pests. Exotic trees may be less susceptible to herbivores but provide less conservation value as a consequence. We tested the hypotheses that native species in Acer and Quercus would have more herbivorous pests than exotic congeners and different communities of arthropod natural enemies. The density of scale insects, common urban tree pests, was greatest on a native Acer and a native Quercus than exotic congeners in both years of our research (2012 and 2016) and sometimes reached damaging levels. However, differences in predator and parasitoid abundance, diversity, and communities were not consistent between native and exotic species in either genus and were generally similar. For example, in 2012 neither predator nor parasitoid abundance differed among native and exotic Acer congeners but in 2016 a native species, A. saccharum, had the least of both groups. A native, Q. phellos, had significantly more predators and parasitoids in 2012 than its native and exotic congeners but no differences in 2016. Parasitoid communities were significantly different among Acer species and Quercus species due in each case to greater abundance of a single family on one native tree species. These native and exotic tree species could help conserve arthropod natural enemies and achieve pest management goals.

The Academic Role of Hong Kong in the Development of Chinese Culture, 1950s–70s

China Report ◽  
2017 ◽  
Vol 54 (1) ◽  
pp. 66-80
Author(s):  
Au Chi Kin
Keyword(s):  
Hong Kong ◽  
Chinese Culture ◽  
Tertiary Education ◽  
Republic Of China ◽  
Academic Role ◽  
Chinese Studies ◽  
The 1960S ◽  
Cultural Bridge ◽  
The University

For many people, ‘Hong Kong is a cultural desert’. However, we find that Hong Kong plays an important academic role and acts as a cultural bridge between China and Western countries, especially when China experiences unstable political, economic, social and cultural situations. The People’s Republic of China was established in 1949. During this time, numerous scholars fled China and selected Hong Kong as a ‘shelter’. Some decided to stay for good, whereas others viewed the territory as a stepping stone. Regardless of their reasons, their academic performance has significantly influenced Hong Kong. Two of the most famous scholars in this period were Luo Xianglin (羅香林 Lo Shan Lin) and Qian Mu (錢穆). Luo taught at the Department of Chinese of the University of Hong Kong. Qian was a faculty member at the New Asia College, which was one of the founding members of the Chinese University of Hong Kong. This study will examine the following issues: (i) why these two scholars selected Hong Kong, (ii) what role they played in the development of tertiary education with regard to Chinese studies in Hong Kong, (iii) how they developed the role of Hong Kong as a haven for the protection of Chinese culture and (iv) how Qian Mu developed New Asia College as a vehicle for spreading the ‘New’ Asian culture in the 1960s.

Coptotermes formosanus (Formosan subterranean termite).

2021 ◽  
Author(s):  
Gregg Henderson
Keyword(s):  
Native Species ◽  
Coptotermes Formosanus ◽  
Subterranean Termite ◽  
Limiting Factor ◽  
Port Cities ◽  
Factors Affecting ◽  
Termite Control ◽  
Exotic Pests ◽  
The Usa ◽  
The 1960S

Abstract C. formosanus is often transported by boats and shipping containers to port cities before being carried further inland via landscape materials such as railroad ties (railway sleepers). This may explain the current C. formosanus distribution in the USA with coastal areas more densely infested than inland areas (Hochmair and Scheffrahn, 2010). Temperature and humidity are primary factors affecting the establishment of C. formosanus, and it is potentially invasive to areas of high humidity approximately 35° north and south of the equator (Su and Tamashiro, 1987). Competition from native species is another limiting factor for many exotic pests, but C. formosanus is more aggressive and is known to out-compete the endemic termites such as Reticulitermes species. Another factor that has allowed the successful establishment and spread of C. formosanus in exotic areas has been the pest control industry's heavy reliance on soil termiticide barriers for subterranean termite control since the 1950s. Numerous studies, using mark-recapture methods, have revealed that a single colony of C. formosanus might contain several million termites that forage up to 100 m in the soil (Lai, 1977; Su and Scheffrahn, 1988). These agree with the results of excavation studies for C. formosanus colonies (Ehrhorn, 1934; King and Spink, 1969). Because of the large colony size, the application of soil termiticides beneath a structure does not usually have a major impact on the overall population, and the surviving colony continues to produce alates that can further infest nearby areas. Once established, C. formosanus has never been completely eradicated from an area. The dependency of soil termiticide barriers as the primary tool for subterranean termite control is probably the main reason for the establishment and spread of C. formosanus from four isolated port cities in the 1960s in the USA to all south-eastern states by 2001.

scholarly journals Factors Associated with Urban Risk-Taking Behaviour during 2018 Typhoon Mangkhut: A Cross Sectional Study

2020 ◽  
Vol 17 (11) ◽  
pp. 4150
Author(s):  
Evan Su Wei Shang ◽  
Eugene Siu Kai Lo ◽  
Zhe Huang ◽  
Kevin Kei Ching Hung ◽  
Emily Ying Yang Chan
Keyword(s):  
Hong Kong ◽  
Risk Perception ◽  
High Risk ◽  
Extreme Events ◽  
Risk Taking ◽  
Sensation Seeking ◽  
Risk Behaviour ◽  
Disaster Risk ◽  
Cross Sectional ◽  
High Risk Behaviour

Although much of the health emergency and disaster risk management (Health-EDRM) literature evaluates methods to protect health assets and mitigate health risks from disasters, there is a lack of research into those who have taken high-risk behaviour during extreme events. The study’s main objective is to examine the association between engaging in high-risk behaviour and factors including sociodemographic characteristics, disaster risk perception and household preparedness during a super typhoon. A computerized randomized digit dialling cross-sectional household survey was conducted in Hong Kong, an urban metropolis, two weeks after the landing of Typhoon Mangkhut. Telephone interviews were conducted in Cantonese with adult residents. The response rate was 23.8% and the sample was representative of the Hong Kong population. Multivariable logistic regressions of 521 respondents adjusted with age and gender found education, income, risk perception and disaster preparedness were insignificantly associated with risk-taking behaviour during typhoons. This suggests that other factors may be involved in driving this behaviour, such as a general tendency to underestimate risk or sensation seeking. Further Health-EDRM research into risk-taking and sensation seeking behaviour during extreme events is needed to identify policy measures.

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