As climate warms, the impact of existing urban heat islands on the health of residents in towns and cities will worsen. A reduction in impervious in cities may help to reduce temperatures, but the relationship between tree canopy coverage and land surface temperature (LST) is not well characterised. Here, we quantified the summer LST of the temperate city of Leeds, UK using Landsat 8 TIRS remote sensing image and explored the spatial relationships between LST and impervious land cover, greenspace coverage, type of greenspace and canopy cover. We found a strong relationship between LST and canopy coverage across the built-up region of Leeds and use this relationship to project the impact of future canopy cover expansion. We found that of the nine main types of greenspaces in Leeds, private gardens occupied the greatest fraction of the total greenspace area and offered most potential for canopy cover expansion. Results suggest that a doubling of canopy coverage across the city, could reduce the mean LST by around 2.5 degrees C during the warmest summer months. Such a temperature reduction adds further weight to efforts by cities and countries globally to increase tree cover to both mitigate for and adapt to climate change.

Robotics and autonomous systems are reshaping the world, changing healthcare, food production and biodiversity management. While they will play a fundamental role in delivering the UN Sustainable Development Goals, associated opportunities and threats are yet to be considered systematically. We report on a horizon scan evaluating robotics and autonomous systems impact on all Sustainable Development Goals, involving 102 experts from around the world. Robotics and autonomous systems are likely to transform how the Sustainable Development Goals are achieved, through replacing and supporting human activities, fostering innovation, enhancing remote access and improving monitoring. Emerging threats relate to reinforcing inequalities, exacerbating environmental change, diverting resources from tried-and-tested solutions and reducing freedom and privacy through inadequate governance. Although predicting future impacts of robotics and autonomous systems on the Sustainable Development Goals is difficult, thoroughly examining technological developments early is essential to prevent unintended detrimental consequences. Additionally, robotics and autonomous systems should be considered explicitly when developing future iterations of the Sustainable Development Goals to avoid reversing progress or exacerbating inequalities.

With a rapid pace of urbanization, urban environment problems have affected large numbers of people and aroused widespread concern. Landscape architecture design helps improve the welfare of urban residents and ecological function of urban green spaces. Course-based influence of college students majoring in landscape architecture is an efficient way to prepare future landscape architects with environmental awareness. This research applied project-based learning (PBL) and zone of proximal development (ZPD) in the landscape architecture design course, and developed the investigation–design–construction PBL modules of the course. The experimental group, 57 college juniors majoring in landscape architecture, received PBL education while learning the course. At the end of the course, a questionnaire was answered by the junior students and the control group, which comprised 60 senior students who received no PBL instruction while learning the same course in the third year. The results indicate that the PBL approach was well accepted by 90% of the experimental group, who were 17.37% more likely to employ pro-environmental design methods in their future work than the control group. It was also found that employing the PBL approach in the landscape architecture design course had a positive influence upon students’ pro-environmental values, knowledge and attitudes.

The Urban Heat Island Effect (UHIE) is a widely recognised phenomenon that profoundly affects the quality of life for urban citizens. Urban greenspace can help mitigate the UHIE, but the characteristics that determine the extent to which any given greenspace can cool an urban area are not well understood. A key characteristic is likely to be the properties of trees that are found in a greenspace. Here, we explore the sensitivity of the strength of the cooling effect to tree community structure for greenspaces in Changzhou, China. Land surface temperatures were retrieved from Landsat 7 ETM+ and Landsat 8 TIRS and were used to evaluate the temperature drop amplitude (TDA) and cooling range (CR) of 15 greenspaces across each of the four seasons. Tree community structure of the greenspaces was investigated using 156 sample plots across the 15 greenspaces. We found that a number of plant community structure indicators of greenspaces have a significant impact on the strength of the cooling effect. The Shannon-Wiener diversity index, tree species richness and tree canopy coverage of greenspaces are all positively correlated with the magnitude of the temperature drop amplitude, with the strength of their influence varying seasonally. We also find that mean crown width is positively correlated with cooling range in summer and autumn, while greenspace tree density is negatively correlated with cooling range in winter. Our findings improve understanding of the relationship between plant community structure and the cooling effect of greenspaces. In particular, we highlight the important role that tree species diversity provides for mitigating the UHIE, and suggest that if planners wish to improve the role of urban greenspaces in cooling cities, they should include a higher diversity of trees species.

Street trees provide essential ecosystem services and are important to local residents’ life, but there has not been much research on the structure of street trees in the city of Changzhou, China. This research surveys the structure of street trees in Changzhou with the aid of geospatial technologies and field sampling surveys. An investigation of the street trees on the 220 sampled transects of streets across the four districts of Changzhou reveals prominent problems with the species diversity, distribution, age structure, and density. Though street tree density in the city is approximately 177/Km, higher than many other cities in the world, with only 29 street tree species in 19 families and 27 genera, the diversity is lower. Among the tree species, only a limited few are planted widely. Young trees account for 43.2% of the total tree population, while large old trees decrease in number. Close spacing between trees, caused by unreasonably high density, results in enormous government expenses on pruning. These findings highlight the need for careful selection of appropriate tree species on the part of municipal administrators and planners. Suggestions are given on how to achieve a sustainable structure of street trees in Changzhou in the long run. Both the problems found and the corresponding suggestions are of referential meaning to the street tree development of other cities in China.

Green roofs can improve urban ecological conditions by mitigating the heat island effect and absorbing harmful gases. Soil additives can improve roof soil properties and promote the stability of the urban ecosystem. As soil additives, biochar and sludge are widely used in the ground, but their application on roofs is still scarce. This study examined the carbon storage potential of green roofs amended with sludge and biochar. The roof soil was composed of soil and varying proportions of the additives (0%, 5%, 10%, 15%, and 20%, v/v); Sedum lineare was then planted. The carbon contents of the soils and plants were measured for one year. The influence of biochar or sludge on the carbon content of the roof soil and the factors affecting the roof carbon storage potential were analyzed. The results showed that the carbon storage potential of a biochar green roof (9.3 kg C m−2) was significantly higher than that of a sludge green roof (7.9 kg C m−2). Biochar increased the carbon content of the green roof by improving the physical properties of the roof soil and promoting plant growth, whereas sludge increased the carbon content of the green roof by improving the chemical properties of the roof soil. Moreover, biochar could not only store large amounts of stable carbon, but also reduce the weight of the green roof, improve soil moisture, and provide a resourceful utilization of municipal sludge. Thus, biochar can be considered a material for promoting carbon storage on green roofs.

The Land Surface Temperature (LST) of a park is lower than the surrounding environment, and thus the parkland forms a Park Cool Island (PCI). However, more case studies are needed to reveal the relationship between park composition, vegetation characteristic and PCI development. The LST and Land Use/Land Cover (LULC) of 18 different sized parks in Changzhou, China were obtained from Landsat-8 and Mapworld Changzhou data. Then, a sample investigation method was used to calculate vegetation characteristics of these parks by an i-Tree Eco model. In order to reduce the impact from the external environment on PCI, the Temperature Drop Amplitude (TDA) and Temperature Drop Range (TR) inside the parks were analyzed by ArcGIS 9.3. Impact factors were tested by Pearson correlation analysis and curve fit to reveal the relationship between these factors and PCI formation. The result shows that a park area threshold of 1.34 to 17 hectares provides the best PCI effect, that park shape (perimeter/area), Leaf Area Index (LAI), density, tree cover, water cover, and impervious surface cover have significant correlation with PCI development, vegetation health and global climate change affect the PCI development. Advice is proposed to improve and maintain PCI effects.