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The world is urbanizing at an unprecedented rate, with the United Nations projecting that 68% of the world’s population will be living in urban areas by 2050. In Southeast Asia (SEA) region, it is expected that 47% of the population will live in urban areas by 2025. Urbanization patterns in this region are generally associated with rapid population growth, economic development and competing demands for land. SEA is also a hotspot of tropical deforestation due to rapid urbanization, resulting in detrimental impacts to the environment and associated ecosystem services. For example, changes in vegetation due to land use/ land cover (LULC) change impact the thermal environment. The objectives of this study are to i) calculate the land cover changes between 2000 and 2020 for 20 major SEA urban clusters; ii) characterise the change in urban form within SEA urban clusters via landscape metrics used at the neighbourhood-scale; iii) determine the relationship between landscape metrics and urban heat measured by LST; and iv) determine the relationship between landscape metrics and vegetation indices such as NDVI and EVI. Documenting the LULC transitions (2000 – 2020) and the associated impacts on urban heat and vegetation changes can help inform policy, sustainable land management and ecosystem services management using Nature based Solutions. We discuss the results per country, contrasting results for major cities and secondary cities, which show different changes in landscape.

The variation of tourism flow and its spatial representation are indispensable for transport companies, accommodation facilities and future estimations regarding the international arrivals. The major implication for tourism flow mapping is related to the country of origin of tourists, their liquid assets, and tourism statistical database. The approach of tourism flow mapping representation, at least using lines and density, should be based on the spatial characteristics of the objects. In this study, the database consisting of international arrivals in different cities of Romania was used as an example. Thus, GIS-based Kernel density of the tourists’ flow was proposed. To illustrate the international demand, data on arrivals for 33 countries over the period 2015-2017 were used. ‘XY To Line’ and ‘Kernel Density’ functions served to create the convergence lines between the origin countries and Romania. The very high density was found for the European countries with an increase of 13% and 25% between 2015 and 2016, as well as between 2015 and 2017. Map analysis indicated an increase of the density area by 0.7% for 2016 and 1.7% for 2017. The proposed methods, including lines and density, contribute to the mapping of the flow of the international arrivals in Romania.

In this paper, we determine the groundwater vulnerability of the Iberian Peninsula on the spatial scale. Aquifers, infiltration map, water availability, pollution load index, and nitrate (NO3) data have been analyzed as independent factors and inserted into the “New Implemented Spatial-Temporal On Regions–Groundwater Vulnerability Index” (NISTOR-GWV index) model in the Geographical Information Systems platform in order to generate the groundwater vulnerability map of the Iberian Peninsula. The new approach, called the NISTOR-GWV index, was applied on current (2011–40: 2020s) and future periods (2041–70: 2050s). During the 2020s, high and very high vulnerability of groundwater are depicted in the Ebro River Basin, in the Tejo Valley, in the Baetic Depression, and in the Meseta Central. The vulnerability map indicates larger areas of high vulnerability class during the 2050s. The future scenarios show a significant decrement in the areas with low and very low vulnerability classes (scenario B2) in comparison with the current period, while the areas with the high and very high vulnerability increased for the 2050s (scenario B1). These results would seem to show that climate change and land cover modifications negatively affect the groundwater resources, mostly at the spatial scale. The most important implications to protect the aquifers could be addressed to the agriculture and environmental management planning. A good planning of water consumption, agricultural and irrigation water use in Spain and Portugal may lead to a reduction of climate impact on groundwater.

This study analysed urban growth patterns for 15 Southeast Asian cities using remotely sensed night-time light data from1992 to 2012. We extracted three urban categories (countryside, peri-urban, and core-urban) for each city using objectively derived thresholds from the brightness gradient (BG) approach. The peri-urban and coreurban combined categories were generally found to increase over time for all cities whereas countryside urban category decreased implying strong spatial and temporal trends in urbanization. These trends were also found to be sensitive to geographic characteristics of cities. The study showed that the BG approach can be successfully applied to extract and study growth dynamics of different urban categories for Southeast Asian cities having range of demographic and socioeconomic conditions. The BG derived urban categories compared favourably with Landsat derived impervious areas, where the former was found to envelope the high percentage impervious region derived from the latter. The BG-derived urban areas are lastly compared against the population data to explore linkages with population growth. NRF (Natl Research Foundation, S’pore) Accepted version