Molluscs community as a keystone group for assessing the impact of urban sprawl at intertidal ecosystems

Mollusc communities are getting endangered in the aftermath of urban sprawl because artificial structures do not surrogate natural substrates. In this study, we compared the diversity, community and trophic arrangements of molluscs among different models of artificial substrate and their adjacent natural rock, to detect relationships between some abiotic variables and the mollusc communities. Complexity, chemical composition and age were tested as potential drivers of the community. Diversity, community and trophic structure differed between natural and artificial substrates. Complexity at the scale of cm was detected as the most important factor driving the community structure. In addition, a chemical composition based on silica and/or scarce calcium carbonates seems to be relevant for molluscs, as well as for the secondary substrate where they inhabit. However, age did not seem to be a driving factor. Among the different artificial structures, macroscale complexity was detected as the main factor diverging a drastically poor community at seawall from other artificial structures. In this context, macro and microscale complexity, chemical composition and mineral type are variables to consider in future designs of artificial substrates.

A kelet-közép-európai városrégiók átalakulása a posztfordi korban – elméleti alapok

The post-Fordist and post-socialist transition had a significant impact on the development of cities in East Central Europe. One of the most spectacular processes in the development of postsocialist cities has been the transformation of the inner areas and outskirts of the urban regions. In the inner areas, after the regime change, urban regeneration gained momentum and thanks to the prevailing neoliberal urban policies almost without exception triggered gentrification processes in the neighbourhoods. Outside the administrative boundaries of the city, in the agglomeration zone and in the more remote areas of the urban region, suburbanisation and urban sprawl have determined the development process. As a consequence, the previously compact urban fabric of post-socialist cities slowly disintegrated and cities became more and more fragmented. The aim of this theoretical study is to explore the most important processes of urban transformation in the post-Fordist era. We briefly introduce the theoretical background of metropoliszation, suburbanization and urban sprawl, as well as the main characteristics of commuting and land use. The role of urban regeneration and fragmentation in the urban fabric will be highlighted as well.

Photovoltaic Solar Energy from Urban Sprawl: Potential for Poland

Urban sprawl is a process that shapes contemporary urban spaces. Generally, this process is associated with negative effects due to the generation of high costs. However, not all the effects of urban sprawl should be considered in the context of the increasing costs of the use of space; some of them should be regarded as cost cutting factors, for example, the possibility of the use of roofed areas in generating energy from sunlight. Solar energy is believed to be one of the sources of clean energy that reduce pollution and greenhouse gas emissions into the atmosphere. However, solar energy generation necessitates the development of large areas for the purpose of installing photovoltaic modules and substantial funds for creating large solar farms. For this reason, a significant role in state energy policies is played by small dispersed installations mounted on the roofs of buildings. There is a gap in existing research on the assessment of urban sprawl in terms of the potential use of rooftops for solar installations in suburban areas. This research gap has not yet been filled, either conceptually and methodologically. Hence, the contribution of the research to the development of the current state of knowledge involves the identification of economic and environmental benefits of usually negatively perceived urban sprawl. The proposal of a method for the identification of suburban housing potential for solar energy generation constitutes another addition to the state of knowledge. The main objective of this article is to analyse the energy generating potential of buildings located in suburban and urban areas characterised by the confirmed occurrence of urban sprawl phenomena. CityGML data were used to conduct an analysis of the exposure of roofs to sunlight using algorithms based on vector data. The authors estimated the dynamics of changes in time and referred the existing photovoltaic installations to the total potential of a selected area. The use of the energy potential of the analysed roofs of buildings was used to evaluate the external costs and benefits of spatial planning. The discussion presented the current conditions of the energy sector and energy policies in Poland and the EU. In addition, recommendations were proposed for local spatial policies concerning the mitigation of the effects of suburbanization in the context of developing the system of PV micro-installations.