Ph.D.

The regulation of the Manama river, one of the major Orinoco distributary channels, has instigated changes in the hydrological and sedimentological regimes of its channel and surrounding wetlands, covering one-third of the Delta area. The dam has altered the hydrodynamics of the Manama. While the average flow of its channel was reduced from 10% to 0.5% (200 m3/s), of the annual discharge of the Orinoco River. The adjacent Macareo distributary, which is not regulated, discharges 11% (4,000 m3/s) annually. During the seasonal high-water period, the water level in the Macareo rises approximately 7 m, while in the Manama is restricted to an periodic oscillation of 0.7 to 1.2 m due mainly to the tidal influence. This flow reduction not only affects the accretion and erosive processes of the banks, due to the decrease of transport of sediments, but also the composition, distribution and diversity of aquatic plants in the region, particularly along the river shores where the species diversity tend to be lower in the regulated river than in the unregulated. The change in the hydrologic dynamic has promoted broad floating meadows to develop in the upper reaches of the Manama river creating patches of rafting meadows. The cessation of the annual flooding has allowed an extensive intrusion of saline water from the sea, which only occur during the dry season. This has enabled halophytic species, particularly mangrove communities to expand their distribution upriver and has also forced the migration of part of the Delta inhabitants Creole and Indians, resulting in a modification of the distribution of the forest and marsh ecological communities due to the overexploitation of their subsistence resources. The particular characteristics of the region that have remained mostly undisturbed since the dam construction several decades ago, permit a comparison of 30 years period of the long-term physical and biological characteristics of a regulated (Manamo) and unaltered (Maca reo) distributary. This thesis investigates these changes and propose a model of the river regulation effects on the ecosystem properties and an equilibrium model of the disturbance and the gain of a new steady state of the ecosystems compartments.

No description available.

The concept of Ecosystem services was developed mainly in the 1980’s, but one of the most important milestones in that process was publication of Millennium Ecosystem Assessment in 2005 which divided ecosystem services into four different types: provisioning, regulating, cultural and supporting. Ecosystem services are being degraded in many cases all over the world. Integrating the concept into the planning process may help to improve this situation. Sweden and Stockholm have long tradition in spatial planning, but there is still a lot to improve when it comes to sustainable management of ecosystem services. One of the reasons is that there is a lack of holistic perspective in planning and systems thinking might be a tool to decrease this deficiency. The aim of the project is to identify the most representative and significant ecosystems in Stockholm County and explain the dynamics within the system of maintenance of ecosystem services on the both regional and local level of planning in Stockholm County. The research has been conducted using literature review as well as semistructured interviews with the most significant stakeholders who are involved in physical planning in Stockholm County both on regional and municipal level. During the interviews five Causal Loop Diagrams (CLDs) where developed. The study concludes that four most representative ecosystems in Stockholm County are: Lake Mälaren, Local green structures, Green wedges and Rural areas. They provide various types of ecosystem services, but the most important and strategic ones seem to be regulating and cultural types since they were the ones easily (and in biggest number listed by the interviewees). The research furthermore concludes that the biggest threats for the identified ecosystems are connected with development of the County, growing population and pressure from the building industry as well as the climate change. Physical planning in Stockholm County has the opportunity to counteract these threats by implementing the concept of ecosystem services planning process and due to collaborative work between municipalities. It is also important to distinguish between ecosystem services per se and what is a requirement for the provision of ecosystem services. In the future this qualitative research could be supplemented with a more detailed/quantitative studies which would contribute to better estimation the results of different planning decisions and include the money factor which have not been researched in this study.

Ecological networks are complex systems forming hierarchical structures in which energy and matter is transferred between the network’s compartments. Predicting energy flows in food webs usually involves complex parameter-rich models. In this thesis, the application of the principle of maximum entropy (MaxEnt) to obtain least biased probability distributions based on prior knowledge is proposed as an alternative to predict the most likely energy flows in food webs from the network topology alone. This approach not only simplifies the characterisation of food web flow patterns based on little empirical knowledge but can also be used to investigate the role of bottom-up and top-down controlling forces in ecosystems resulting from the emergent phenomena based on the complex interactions on the level of species and individuals. The integrative measure of “flow extent”, incorporating both bottom- up and top-down controlling forces on ecosystems, is proposed as a principle behind ecosystem evolution and evaluated against empirical data on food web structure. It could be demonstrated that the method of predicting energy flow with the help of MaxEnt is very flexible, applicable to many different setting and types of questions in ecology, and therefore providing a powerful tool for modelling the energy transfer in ecosystems. Further research has to show in how far the most likely flow patterns are realised in real-word ecosystems. The concept of flow extent maximisation as a selection principle during ecosystem evolution can enhance the understanding of emergent phenomena in complex ecosystems and maybe help to draw a link between thermodynamics and ecology.

<p>Global biodiversity is currently being lost at an unprecedented rate, posing a threat to vital ecosystems and hence the generation of ecosystem services that human society is entirely reliant upon. Within the European Community, the EU has set a target of halting biodiversity loss within the territory by 2010. This goal is intended to be operationalized by the implementation of the Habitats Directive and the Birds Directive. These directives constitute the framework for the establishment of a coherent ecological network, referred to as the Natura 2000 network.</p><p>This study examines and analyses the socio-ecological complexities surrounding the designation of Natura 2000 sites in Östhammar municipality, Sweden. The use of a case study-approach to focus on this area is applied in pursuit of identifying and explaining the inherent intricacies in the designation processes and linking them to the broader global context. Throughout Europe, biodiversity exists in a rich variety of grasslands, but only a few studies have been performed to establish appropriate conservation management strategiesrequired for each habitat. This study makes a significant contribution towards shedding light on the Natura 2000 designation process, a phenomenon which has previously been only modestly documented, especially in Sweden. Ecosystem management is discussed and utilized as the theoretical basis for managing ecosystems sustainably, and an important aspect of note is the recognition that the distinction between man and nature needs to be understood as artificial and arbitrary.</p><p>The study explains how social-ecological factors have had a prominent effect on the designation process of Natura 2000 sites. The main determining factor behind the designation process has been the time-constraints, which have affected the designation of SCIs as well as the interaction between the Uppsala CAD and local stakeholders. The lack of adequate participatory approaches used during this process has heightened the risk of compromising the aim of the network: to achieve Favourable Conservation Status (FCS) for natural habitat types as well as species.</p> / <p>Biodiversiteten världen över minskar i en tidigare aldrig skådad hastighet vilket resulterar i ett hot mot fundamentala ekosystem, samt dess produktion av de ekosystemtjänster som det mänskliga samhället är beroende av. På grund av detta har EU satt upp målet att stoppa förlusten av biodiversitet inom unionens gränser tills 2010. Detta mål skall uppnås genom implementeringen av Habitat- och Fågeldirektivet. Dessa direktiv utgör ramen för etableringen av ett sammanhängande ekologiskt nätverk, det så kallade Natura 2000 nätverket.</p><p>Denna studie utreder samt analyserar de socio-ekologiska aspekter som omger utpekandet av Natura 2000 områden i Östhammars kommun, i Uppsala län i Sverige. Genom appliceringen av en fallstudie av området söker denna uppsats att identifiera samt förklara inneboende svårigheter i processen av dessa utpekanden, samt att sätta dem i ett globalt sammanhang. Inom Europa existerar biodiversitet bland annat i olika typer av ängar, dock har endast ett fåtal studier tagit sig an uppgiften att formulera anpassade förvaltningsstrategier för dessa habitat. Denna studie bidrar till att sprida ljus över implementeringen av Natura 2000, ett fenomen som tidigare endast studerats i blygsam utsträckning, speciellt i Sverige. Den teoretiska grunden utgörs ekosystemansatsen, som appliceras för att utvärdera ett uthålligtförvaltande av ekosystem. Vidare understryks vikten av att betrakta ekosystem och mänsklig aktivitet som ett och samma system, och att synen på dem som skilda system bör anses artificiell och motsägelsefull.</p><p>Denna uppsats förklarar hur socio-ekologiska aspekter har påverkat utpekandeprocessen av Natura 2000-områden i Östhammars kommun. De avgörande faktorerna bakom detta är en identifierad tidsbrist, vilket har influerat utpekandet av områden av gemenskapsintresse samt interaktionen mellan Länsstyrelsen i Uppsala och lokala markägare. Bristen på samverkan och information har resulterat i en förhöjd risk av att målet med nätverket inte kommer att nås: att åstadkomma gynnsam bevarandestatus för arter och habitat.</p>

Global biodiversity is currently being lost at an unprecedented rate, posing a threat to vital ecosystems and hence the generation of ecosystem services that human society is entirely reliant upon. Within the European Community, the EU has set a target of halting biodiversity loss within the territory by 2010. This goal is intended to be operationalized by the implementation of the Habitats Directive and the Birds Directive. These directives constitute the framework for the establishment of a coherent ecological network, referred to as the Natura 2000 network. This study examines and analyses the socio-ecological complexities surrounding the designation of Natura 2000 sites in Östhammar municipality, Sweden. The use of a case study-approach to focus on this area is applied in pursuit of identifying and explaining the inherent intricacies in the designation processes and linking them to the broader global context. Throughout Europe, biodiversity exists in a rich variety of grasslands, but only a few studies have been performed to establish appropriate conservation management strategiesrequired for each habitat. This study makes a significant contribution towards shedding light on the Natura 2000 designation process, a phenomenon which has previously been only modestly documented, especially in Sweden. Ecosystem management is discussed and utilized as the theoretical basis for managing ecosystems sustainably, and an important aspect of note is the recognition that the distinction between man and nature needs to be understood as artificial and arbitrary. The study explains how social-ecological factors have had a prominent effect on the designation process of Natura 2000 sites. The main determining factor behind the designation process has been the time-constraints, which have affected the designation of SCIs as well as the interaction between the Uppsala CAD and local stakeholders. The lack of adequate participatory approaches used during this process has heightened the risk of compromising the aim of the network: to achieve Favourable Conservation Status (FCS) for natural habitat types as well as species. / Biodiversiteten världen över minskar i en tidigare aldrig skådad hastighet vilket resulterar i ett hot mot fundamentala ekosystem, samt dess produktion av de ekosystemtjänster som det mänskliga samhället är beroende av. På grund av detta har EU satt upp målet att stoppa förlusten av biodiversitet inom unionens gränser tills 2010. Detta mål skall uppnås genom implementeringen av Habitat- och Fågeldirektivet. Dessa direktiv utgör ramen för etableringen av ett sammanhängande ekologiskt nätverk, det så kallade Natura 2000 nätverket. Denna studie utreder samt analyserar de socio-ekologiska aspekter som omger utpekandet av Natura 2000 områden i Östhammars kommun, i Uppsala län i Sverige. Genom appliceringen av en fallstudie av området söker denna uppsats att identifiera samt förklara inneboende svårigheter i processen av dessa utpekanden, samt att sätta dem i ett globalt sammanhang. Inom Europa existerar biodiversitet bland annat i olika typer av ängar, dock har endast ett fåtal studier tagit sig an uppgiften att formulera anpassade förvaltningsstrategier för dessa habitat. Denna studie bidrar till att sprida ljus över implementeringen av Natura 2000, ett fenomen som tidigare endast studerats i blygsam utsträckning, speciellt i Sverige. Den teoretiska grunden utgörs ekosystemansatsen, som appliceras för att utvärdera ett uthålligtförvaltande av ekosystem. Vidare understryks vikten av att betrakta ekosystem och mänsklig aktivitet som ett och samma system, och att synen på dem som skilda system bör anses artificiell och motsägelsefull. Denna uppsats förklarar hur socio-ekologiska aspekter har påverkat utpekandeprocessen av Natura 2000-områden i Östhammars kommun. De avgörande faktorerna bakom detta är en identifierad tidsbrist, vilket har influerat utpekandet av områden av gemenskapsintresse samt interaktionen mellan Länsstyrelsen i Uppsala och lokala markägare. Bristen på samverkan och information har resulterat i en förhöjd risk av att målet med nätverket inte kommer att nås: att åstadkomma gynnsam bevarandestatus för arter och habitat.

“Payments for ecosystem services” (PES) represents a new form of environmental governance rooted in the logics of capitalist economics. As such, PES frequently produces new conceptions and material forms of nature that embody the principles of neoliberal ideology. This thesis explores the processes by which these policies have been deployed and taken root in Costa Rica, one of the foremost sites of financialized conservation worldwide. It provides a historical account of policy formation and the neoliberalization of Costa Rican nature. I situate this analysis in a critique of capitalist logic, explaining the particular type of neoliberalization that emerges as a consequence of capital's own internal contradictions. I place particular emphasis on ideological inconsistencies in the deployment of neoliberal ideals while highlighting the justice implications that inevitably still emerge. I do so by adopting a critical political-ecology perspective that sees questions of environmental management as fundamental questions of social and environmental justice – how are conservation mechanisms designed, by whom, for what purposes, and to whose ultimate benefit? Specifically, I consider three aspects of neoliberalization in Costa Rica's national Pagos por Servicios Ambientales (PSA) program: the design of a new market-like financing mechanism; the promotion of individualized contracting and participation; and the expansion of exclusionary land management practices. I show that these actions produce the conditions for uneven development, facilitate the consolidation of control over resources, and enable the accumulation of benefits among larger, wealthier landowners. I further explore conceptual understandings of neoliberalism (as ideology or process) and address the growing concern in the critical literature with ways that policy deviates from doctrine. I explain that such an emphasis on ideologically divergent practice distracts from the material and justice effects of encroaching neoliberalization, which invariably operates in partial and unfinished ways. Finally, I revisit the role of the internal contradictions of capital in producing the patterns of governance that constitute this era of neoliberal environmentalism.

No description available.

Recovery of tropical rain forest in Gogol Valley, Papua New Guinea was monitored for 2 years following clear-fel1ing in the wet and dry seasons. Further redevelopment, reconstructed by measurements of regrowth of known ages from 1.5-10.8 years, were compared with forest heavily disturbed by fire 55 years ago and primary forest. The vegetation, survey was assessed principally by Counting and measuring trees. Because of the importance of soil seed bank in influencing vegetation recovery processes, special attention was given to the spatial and temporal changes in the soil seed bank and the seed rain which supplies it. The major findings were: (1) vegetation recovery was rapid and 97% of all colonizing trees regenerated from seeds while 3% were resprouts; (2) regrowth after felling in the dry-season differed from that following wet-season felling in having lower density, slower growth and mostly comprised resprouting tree species; (3) after 10 years, regrowth is composed principally of large pioneer trees (65% of basal area or 64% of stems); (4) the 55 year-old forest also had many (48%) pioneer trees: much of the forest in the area is of this kind and may be classified as advanced secondary forest; (5) forest soil seed bank following felling was rapidly depleted due to germination, but was rapidly replaced as early pioneer herbs matured and set seed. Trees in soil seed bank do not approach that of primary forest until after 10 years of regrowth; (6) the intensity of pioneer trees' seed rain was correlated with the fecundity of nearby parent trees and clearly controlled soil seed bank redevelopment. There was evidence of dispersal of pioneer seeds several hundred metres into an isolated area of closed forest; (7) trees left uncut following felling contribute significantly to seed rain and therefore to soil seed bank.