Publications

With climate change, some coastal urban regions once characterized by mild oceanic climates, are becoming increasingly hot in the summer. Urban design can modify urban landscapes to mitigate the Urban Heat Island (UHI) effect, but many strategies are constrained in high-density urban centers where large-scale layouts are difficult to alter. Yet noting that streets are among the more modifiable public spaces in high-density urban areas, this paper examines how relationships between street-level Sky View Factors (SVF), other indicators of urban morphology, and UHI are interconnected in different parts of a mid-latitude coastal urban area, Metro Vancouver.

This study found an expected positive correlation coefficient of 0.484 (p < 0.05) between SVF and UHI intensity before considering other variables and spatial context. In areas that are equally distant from water bodies, have similar forest cover near streets, and possess comparable urban patch sizes, a 0.2 decrease in SVF (which ranges from 0 to 1) corresponds to a reduction of 0.08 °C–0.15 °C in urban heat island intensity (measured in ∆LST).

Yet when supplementing aspatial OLS regression with geographically weighted regression (GWR), the study is able to identify how a number of commonly understood individual relationships between SVF, urban morphology, and UHI are actually substantially and consequentially variable in effect and significance depending on geographical context. In areas closer to the coast, SVF's effects on UHI are not significant, but with increasing distance to the sea, SVF has significant and greater influence on UHI intensity.

Additionally, scale matters–water has a weak negative correlation (−0.291) with UHI intensity at a more granular 150 m scale but moderate negative correlation (0.463) at the coarser scale of 900 m gridded data; forest cover provides stronger heat island mitigation at small scales (0.73 at 150 m; while 0.62 at 900 m).

The study illustrates how methods attentive to geographical context and spatial interactions can serve as the basis for more locally appropriate planning recommendations as well as for more robust generalizations about what can cause and mitigate UHI. Our findings suggest creating more street shading and promoting accessibility to heat sinks, especially in urban areas farther from the coast, while also offering guidance on integrating societal contexts more directly into UHI research as concerns about climate inequalities grow.

Qilian Mountain National Park (QLMNP) is a biodiversity hotspot with great agriculture and tourism resources. With the expansion of human activities, a few areas of the park are experiencing massive landscape transformation, and these areas are also highly ecologically sensitive. Nevertheless, there are substantial differences in the human activities and natural resources of various communities around QLMNP, resulting in heterogeneous landscape degradation.

Hence, this study explores the extent and drivers of spatial heterogeneity in landscape fragmentation associated with ecologically vulnerable communities in QLMNP. Multiple ring buffer analysis and geographically weighted regression (GWR) were used to analyze the relationships between landscape fragmentation and variables of human activities and facilities to identify the main factors influencing landscape fragmentation in different regions.

The results reveal that human disturbance had a stronger relationship with landscape fragmentation in QLMNP than natural factors do. Among the drivers of landscape fragmentation, the distribution of residential areas and the extension of agricultural land were found to have more significant impacts than tourism.

Expansion of cropland had a greater impact on the eastern part of the national park, where overgrazing and farming require further regulation, while tourism affected the landscape fragmentation in the central area of the national park. The point-shaped human disturbance had a larger impact than the linear disturbance.

The study findings can be used to formulate a comprehensive plan to determine the extent to which agriculture and tourism should be developed to avoid excessive damage to the ecosystem.