Search results for "Linkages"
showing 9 items of 9 documents
Fish introductions and light modulate food web fluxes in tropical streams: a whole-ecosystem experimental approach.
2016
Decades of ecological study have demonstrated the importance of top-down and bottom-up controls on food webs, yet few studies within this context have quantified the magnitude of energy and material fluxes at the whole-ecosystem scale. We examined top-down and bottom-up effects on food web fluxes using a field experiment that manipulated the presence of a consumer, the Trinidadian guppy Poecilia reticulata, and the production of basal resources by thinning the riparian forest canopy to increase incident light. To gauge the effects of these reach-scale manipulations on food web fluxes, we used a nitrogen (15 N) stable isotope tracer to compare basal resource treatments (thinned canopy vs. co…
Grazing decreases N partitioning among coexisting plant species
2017
Herbivores play a key role in shaping ecosystem structure and functions by influencing plant and microbial community composition and nutrient cycling. This study investigated the long‐term effects of herbivores on plant resource acquisition. We explored differences in the natural δ15N signatures in plant, microbial and soil N pools, and examined mycorrhizal colonization in two tundra sites that have been either lightly or heavily grazed by reindeer for more than 50 years. The study examined changes in nutrient acquisition in five common tundra plants with contrasting traits and mycorrhiza status; the mycorrhizal dwarf shrubs, Betula nana, Vaccinium myrtillus and Empetrum hermaphroditum; a m…
Network governance arrangements and rural-urban synergy
2021
Increasing attention has been paid to the importance of balanced rural–urban interaction to sustainable regional development. Yet, our knowledge on the elements of network governance for such interaction is scarce. The aim of this paper is to study what kind of network governance arrangements currently exist, how they can be improved, and whether evolutionary governance paths can be identified. We analyse five existing and evolving cases of functioning rural–urban interaction in European Union (EU) member states, using a network governance framework as an analytical lens. We supplement the governance analysis with examining what kind of spatial understanding or combination of di…
Transitioning towards a Sustainable Wellbeing Economy—Implications for Rural–Urban Relations
2021
This article focuses on the question of how a shift from a narrow economic perspective to a wider sustainable wellbeing focus in regional development strategies and actions might change rural–urban relations. A brief review of relevant research and discourses about economic development models provides the foundation for the analysis. The review leads to the development of an analytical framework that puts the notion of sustainable wellbeing at its center. The criteria included in the analytical framework are then used to assess the current situation, challenges and perceived ways forward based on data and analyses from 11 European regions. The focus of the analysis is on different exp…
Diagnosis and predictability of intraseasonal characteristics of wet and dry spells over equatorial east Africa
2010
Most of Eastern Africa has arid and semi-arid climate with high space-time variability in rainfall. The droughts are very common in this region, and often persist for several years, preceded or followed by extreme floods. Most of the livelihoods and socio-economic activities however remain rain-dependent leading to severe negative impacts during the periods of occurrence of climate extremes. It has been noted that one extreme event was capable of reversing national economic growth made over a period of several years. Thus no sustainable development can be attained in eastern Africa without effective mainstreaming of climate information in the development policies, plans and programmes. Many…
Regional economic structures in Finland : analyses of location and regional economic impact
2007
This dissertation consists of nine empirical studies which seek to broaden understanding of Finnish regional economic structures. These studies are divided between two topics: 1) regional specialization and industrial concentration in Finland, and 2) regional economic impact analysis. The empirical studies are preceded by an introduction, in which the theoretical background, outline and the main results of the thesis are presented. The research on the first topic is guided by the new economic geography literature, from which answers are sought to the location and agglomeration questions addressed in this dissertation. Evidence is found of increasing post-recession specialization in Finland.…
Data from: Grazing decreases N partitioning among coexisting plant species
2018
1. Herbivores play a key role in shaping ecosystem structure and functions by influencing plant and microbial community composition and nutrient cycling. 2. This study investigated the long-term effects of herbivores on plant resource acquisition. We explored differences in the natural δ15N signatures in plant, microbial and soil N pools, and examined mycorrhizal colonization in two tundra sites that have been either lightly or heavily grazed by reindeer for more than 50 years. The study examined changes in nutrient acquisition in five common tundra plants with contrasting traits and mycorrhiza status; the mycorrhizal dwarf shrubs, Betula nana, Vaccinium myrtillus and Empetrum hermaphroditu…
Fish introductions and light modulate food web fluxes in tropical streams : a whole-ecosystem experimental approach
2016
Decades of ecological study have demonstrated the importance of top-down and bottom-up controls on food webs, yet few studies within this context have quantified the magnitude of energy and material fluxes at the whole-ecosystem scale. We examined top-down and bottom-up effects on food web fluxes using a field experiment that manipulated the presence of a consumer, the Trinidadian guppy Poecilia reticulata, and the production of basal resources by thinning the riparian forest canopy to increase incident light. To gauge the effects of these reach-scale manipulations on food web fluxes, we used a nitrogen (15N) stable isotope tracer to compare basal resource treatments (thinned canopy vs. con…
Tractional Motion Machines extend GPAC-generable functions
2012
In late 17th century there appeared the Tractional Motion instruments, mechanical devices which plot the curves solving differential equations by the management of the tangent. In early 20th century Vannevar Bush’s Differential Analyzer got the same aim: in this paper we’ll compare the Differential Analyzer mathematical model (the Shannon’s General Purpose Analog Computer, or GPAC) with the Tractional Motion Machine potentials. Even if we will not arrive in defining the class of the functions generated by Tractional Motion Machines, we’ll see how this class will strictly extend the GPAC-generable functions.