The role of landscape amenities in regional development: a survey of migration, regional economic and hedonic pricing studies

Quality of life factors continue to gain importance in residential location decisions as well as location decisions of firms. One such factor is an attractive local landscape. The aim of this paper is to provide a survey of the empirical literature on the role of landscape amenities in local economic change. Following common amenity definitions, we define landscape amenities as landscape features that are location-specific, latent non-market input goods that directly enter residents’ utility functions. Using this definition we identify thirty-nine relevant studies that use either migration or regional economic models or hedonic pricing techniques. One result from the analysis of migration and regional economic studies is that intra-country migrants were attracted by amenities about as frequently as by a low tax burden. Effects of amenities on employment and income are less well established. However, many of these studies used rather limited amenity variables. The results from hedonic studies show that a wide variety of local amenity attributes are partly capitalized in housing prices and that studies on a larger geographic scale are more likely to identify a significant a role of amenities. Newly available land cover datasets and spatial analysis tools have the potential to overcome important data limitations of many earlier studies. Future research may thus contribute to a better understanding of the role of landscape amenities in economic change and to a better coordination of regional and environmental policies.landscape amenities, migration, local development, hedonic models, environmental valuation, regional economic modeling, land use

Landscape amenities and local development: a review of migration, regional economic and hedonic pricing studies

With rapid urban expansion and loss of open space, attractive local landscapes will continue to gain importance in location decisions and on political agendas. The present study reviews the evidence on the local economic role of landscape amenities from two major strands of empirical research, migration and regional economic models, and hedonic pricing models. Following common amenity definitions we identify 71 relevant peer-reviewed studies and systematically assess the reported effects of the landscape amenity variables. The migration and regional economic studies suggest that migrants are attracted by amenities nearly as often as by low taxes. Reported effects of amenities on income and employment are less consistent. The hedonic studies suggest that nature reserves and land cover diversity have mostly, open space and forest often, and agricultural land rarely positive effects on housing prices. Studies at larger geographic scales and studies involving urban areas were more likely to identify significant amenity effects. Some limitations of the evidence may be overcome with better datasets and modeling approaches. However, in line with other recent work, the limitations also highlight the need for complementary information from the analysis of political preferences for land-use management

Reproductive Physiology of Aedes (Aedimorphus) vexans (Diptera: Culicidae) in Relation to Flight Potential

Total protein, lipid, and glycogen of Aedes vexans (Meigen) were related linearly to body size at eclosion. Starvation after emergence led to the determination of minimal irreducible amounts of protein, lipid, and glycogen and the availability of the teneral reserves, whereas access to sucrose revealed the potential for reserve synthesis. Glycogenesis and lipogenesis increased reserves ≈10-fold the teneral value within 1 and 2 wk after emergence, respectively. Carbohydrate feeding was an essential behavior before blood feeding and oogenesis commenced. Female flight was tested on a flight mill. Maximal flights of 10-17 km in a single night occurred at 2 wk posteclosion and paralleled maximal reserve syntheses. Comparisons of our laboratory data to host-seeking mosquitoes in the field confirmed our data. The vast majority of maternal lipid was transferred to the yolk when a blood meal was taken, but only a quarter of the blood protein was recovered from mature ovaries. Maternal glycogen was used mainly for flight. Fecundity varied between 20 and 120 eggs per female and was determined largely by body size and blood meal volume. At 27°C, maximal egg numbers were produced, but at 22 and 17°C the caloric yolk content was greater. Females from the southern United States were smaller than females from northern areas. However, southern females had similar fecundity as northern females, and their flight performances were similar. Differences in the reproductive physiology between this species and Ae. aegypti were discusse

Interactive simulations with a stylized scale model to codesign with villagers an agent-based model of bushmeat hunting in the Periphery of Korup National Park (Cameroon)

An agent-based model (ABM) representing snare trapping of blue duikers (Cephalophus monticola) was co-designed and used with local populations to raise their awareness about the sustainability of bushmeat hunting activities in the region of the Korup National Park (South-West Cameroon). Village meetings based on interactive simulations with a stylized scale model were structured in three successive steps. During the first step, an abstract representation of a village surrounded by a portion of forest was co-designed by directly manipulating the computer interface displaying a spatial grid. Then, knowledge about the live-cycle traits and the behavior of blue duikers was shared through the demonstration of the individual-based population dynamics module of the ABM. The objective of the second step, introducing the hunting module of the ABM, was to elicit snare trapping practices through interactive simulation and to calibrate the hunting module by setting a value for the probability of a blue duiker to be caught by a snare trap. In a third step, a more realistic version of the ABM was introduced. The seven villages included in the process were located in the GIS-based spatial representation, and the number of 'Hunter' agents for each village in the ABM was set according to the results of a survey. The demonstration of this realistic version triggered discussion about possible management scenarios, whose results obtained with the finalized version of the ABM will be discussed during next round of village meetings.We present the pros and cons of the method consisting in using at an early stage of theprocess interactive simulations with stylized scale models to specify empirically-based agent-based models. (Résumé d'auteur

Disturbance of forest by trampling: Effects on mycorrhizal roots of seedlings and mature trees of Fagus sylvatica

The effects of disturbance by recreational activities (trampling) on changes in soil organic matter (SOM) and on mycorrhizal roots of seedlings and mature trees were studied in four stands of a beech (Fagus sylvatica L.) forest near Basel, Switzerland. At each site, comparable disturbed and undisturbed plots were selected. Disturbance reduced ground cover vegetation and leaf litter. Beech seedlings had lower biomass after disturbance. Ergosterol concentration in seedling roots, an indicator of mycorrhizal fungi, was lower in two of the four disturbed plots compared to undisturbed plots; these two disturbed sites had especially low litter levels. Based on ergosterol measurements, mycorrhizas of mature trees did not appear to be negatively affected by trampling. Total fine roots and SOM were higher in the disturbed than in the undisturbed plots at three sites. At the fourth site, fine roots and SOM in the disturbed areas were lower than in the undisturbed areas most probably due to nutrient input following picnic activities. Principal component analysis revealed a close correlation between SOM and fine roots of mature trees as well as litter and seedling biomass. Trampling due to recreational activities caused considerable damage to the vegetation layer and in particular to the beech seedlings and their mycorrhizal fine roots, whereas, roots of mature trees were apparently resilient to tramplin

Participatory agent-based simulation to foster dialogue and build trust between local communities and researchers: a case study on bushmeat hunting in the periphery of Korup National Park (South-West Cameroon)

To investigate the sustainability of bushmeat hunting activities in the region of the Korup National Park (South-West Cameroon), an agent-based model (ABM) representing snare trapping of blue duikers (Cephalophus monticola) was co-designed and used with local populations. Village meetings based on interactive computer simulations were structured in three successive steps. During the first step, an abstract representation of a village surrounded by a portion of forest was co-designed by directly manipulating the computer interface. Then, knowledge about the live-cycle traits and the behavior of blue duikers was shared through the demonstration of the individual-based population dynamics module of the ABM. The objective of the second step, introducing the hunting module of the ABM, was to elicit snare trapping practices through interactive simulation and to calibrate the hunting module by setting a value for the probability of a blue duiker to be caught by a snare trap. In a third step, a more realistic version of the ABM was introduced. The seven villages included in the process were located in the GIS-based spatial representation, and the number of 'Hunter' agents for each village in the ABMwas set according to the results of a survey. The demonstration of this realistic version triggered discussion about possible management scenarios based on reducing the number of hunters and/or the number of traps per hunter, but also on setting up temporal (rotating) reserves. A second round ofvillage meetings was organized 8 months later to collectively explore with the finalized version of the ABM the pre-identified management options. The whole process resulted in enhancing the trust-building among the local communities and the research team. Some villagers established an association to promote activities related to environmental management, and the research team was given a plot of land to establish an accommodation belonging to Dschang University in the village. (Texte intégral

Retention forestry and biodiversity conservation: a parallel with agroforestry

peerReviewe

Evaluating Potential Fuel Savings of External Alternative Ground Propulsion Systems

This study evaluates the potential fuel savings from using external Alternative Ground Propulsion Systems (AGPS) at Zurich Airport, based on Automatic Dependent Surveillance–Broadcast (ADS-B) surface trajectory data collected from May 1, 2024, to September 30, 2024. Using the Aircraft Emissions Databank of the International Civil Aviation Organization to analyse conventional taxiing and AGPS-assisted taxiing modes, our research estimates fuel consumption during the taxi phase of departing aircraft. The findings indicate that adopting AGPS could reduce taxi fuel consumption by up to 58.9 %, amounting to 5.77 million kg of jet fuel saved, which is equivalent to 18.23 million kg of CO2 emissions, at Zurich Airport alone. The study highlights the significance of selecting aircraft with longer taxi durations for towing to maximize fuel-saving benefits. Even with limited AGPS resources, substantial reductions can be achieved; for instance, deploying just four AGPS units could cut taxi fuel consumption by up to 33.3 %. While the study offers a promising approach to reducing emissions, it acknowledges that practical challenges, such as the need for operational adjustments, must be overcome to ensure the successful implementation and effective use of AGPS in real-world applications

Birds in the matrix: the role of agriculture in avian conservation in the Taita Hills, Kenya

Agricultural conversion of tropical forests is a major driver of biodiversity loss. Slowing rates of deforestation is a conservation priority, but it is also useful to consider how species diversity is retained across the agricultural matrix. Here we assess how bird diversity varies in relation to land use in the Taita Hills, Kenya. We used point counts to survey birds along a land-use gradient that included primary forest, secondary vegetation, agroforest, timber plantation and cropland. We found that the agricultural matrix supports an abundant and diverse bird community with high levels of species turnover, but that forest specialists are confined predominantly to primary forest, with the matrix dominated by forest visitors. Ordination analyses showed that representation of forest specialists decreases with distance from primary forest. With the exception of forest generalists, bird abundance and diversity are lowest in timber plantations. Contrary to expectation, we found feeding guilds at similar abundances in all land-use types. We conclude that while the agricultural matrix, and agroforest in particular, makes a strong contribution to observed bird diversity at the landscape scale, intact primary forest is essential for maintaining this diversity, especially among species of conservation concern