The purpose of this thesis is to investigate if the application of the ecosystem services concept can provide decision makers and stakeholders with additional relevant information for decisions regarding establishing of aquaculture on a local level, using the Lake Storsjön as a case study. In order to provide this knowledge, three different tasks are carried out within this thesis: the identification of the main ecosystem services provided by Lake Storsjön, the understanding of ecosystem services that will be affected by the expansion of aquaculture and the identification of the services that will be used for a possible expansion of the aquaculture sector. The CICES methodology (Common International Classification of Ecosystem Services) is used to identify the ecosystem services provided by Lake Storsjön. The understanding of the affected ecosystem services is carried out with the use of a Delphi-inspired approach. The identification of the services required for the establishment of aquaculture is driven by a cross-reference matrix. Lake Storsjön provides thirty-nine out of the fifty-nine ecosystem services included in the CICES. About half of these will be effected by environmental impacts connected to operations of ecosystem management required by aquaculture expansion, mostly with a low or medium degree of impact. An increase in the implementation of aquaculture might cause detrimental trade-offs with these ecosystem services: “Wild animals”, “Genetic materials from all biota“, “Disease control”, “Maintaining nursery populations and habitats” and “Filtration/dilution/sequestration/storage/accumulation by ecosystem”. An expansion of the aquaculture sector requires seven of the ecosystem services provided by Lake Storsjön. The vital services for this process are: “Surface water for non-drinking purposes”, “Filtration/dilution/sequestration/storage/accumulation by ecosystem” and “Chemical condition of freshwater”. These services have to be safeguarded and maintained in order to guarantee adequate conditions for an expansion of this sector. At the same time the expansion of aquaculture supports the service “Animals from in situ aquaculture”. The benefits connected to the implementation of aquaculture shall be economically assessed and compared to the actual economic value delivered by the other ecosystem services in order to further understand the positives and negatives outcomes of aquaculture expansion in an ecosystem services perspective. This is considered to be a relevant step for strategic and decision making processes concerning aquaculture expansion in Lake Storsjön. In addition to the economic perspective, it seems that the most relevant factor when discussing planning and development processes towards ecosystem services is the importance of not overshooting the resilience ability of the ecosystem in order to ensure the accessibility of the services to future generations. This belief is recommended to be applied to Lake Storsjön in order to guarantee a conscious expansion of the aquaculture sector on a social, economic and environmental level.

O serviço ecossistêmico de regulação climática global (SERCG) ofertado pelas florestas é reconhecido pelo seu papel crucial na mitigação da mudança climática. Tais ecossistemas atuam como sumidouros de carbono atmosférico por meio do CO2 sequestrado e armazenado nos tecidos vivos dos vegetais. Porém, processos de continuo desmatamento afetam negativamente a capacidade desses ecossistemas em ofertar o SERCG, especialmente em florestas tropicais que possuem alto potencial de ofertar o serviço e sofrem forte pressão devido ao desenvolvimento agroindustrial. As paisagens atlânticas brasileiras são exemplos dessa condição, em especial no estado de São Paulo, onde a vegetação natural foi primordialmente convertida em pastagens e silvicultura. Avaliar e gerenciar os estoques e fluxos de serviços dos ecossistemas em paisagens espacialmente heterogêneas constitui um dos principais desafios da ciência da sustentabilidade da paisagem. Frente a esse contexto, o presente estudo tem o objetivo de avaliar os estudos sobre a valoração ecológica do SERCG da floresta tropical e analisar a oferta deste serviço em paisagens atlânticas pressionadas pela atividade pecuária. Inicialmente, investigamos as tendências e lacunas que envolvem a pesquisa dos atributos biofísicos do SERCG nas florestas tropicais e subtropicais na escala pan-tropical através de uma revisão sistemática da literatura sobre o tema nos últimos 20 anos, de acordo com uma abordagem exploratória qualitativa. Constatamos que as estimativas de estoque de carbono das florestas tropicais apresentam alta variabilidade, que os fatores de influência mais recorrentes sobre o SERCG na literatura são as mudanças no uso da terra e a riqueza de espécies e que o SERCG possui maior número de relações de sinergia que de trade-off com outros SEs. Em um segundo momento, analisamos a oferta do serviço de regulação em paisagens atlânticas do Vale do Paraíba do Sul (SP), considerando o processo de substituição de floresta nativa por campo antrópico. Levantamos dados em campo para o cálculo de biomassa acima do solo de fragmentos florestais em diferentes estágios sucessionais e em campo antrópico, e transformamos esses dados em estoques de carbono. Os dados subsidiaram os cálculos de SERCG para 16 paisagens que tinham diferentes proporções de áreas de floresta e campo. Também avaliamos a influência da configuração da paisagem sobre a produção de biomassa dos remanescentes florestais. Obtivemos valores de estoque de carbono de 16,9±7,25 MgC há-1 para a floresta inicial, 34,8±12,05 MgC ha-1 para floresta intermediária-avançada e 0,53±0,26 MgC ha-1 para campo antrópico. Identificamos que a distância ao fragmento mais próximo diminui a biomassa das florestas em estágio inicial, enquanto a área média dos fragmentos localizados em um raio de 500 m ao redor do fragmento amostrado aumenta a biomassa das florestas em estágio intermediário-avançado. Destacamos o fato de que as paisagens avaliadas com > 40% do território florestado possuem um diferencial na contribuição da oferta do SERCG, devido ao aumento em número e área de fragmentos de floresta em estágio intermediário-avançado. Apesar do contraste entre a contribuição dos pequenos fragmentos em estágio inicial e os de estágio mais avançado, a ocorrência dos primeiros implica em uma maior oferta do SERCG em escala de paisagem. Ademais, a conservação desses fragmentos não só influenciaria na oferta do serviço de regulação climática, mas também na oferta de outros com os quais apresenta relações sinérgicas / The global climate regulation ecosystem service (GCRES) provided by forests is recognized for its crucial role in mitigating climate change. These ecosystems act as sinks of atmospheric carbon by sequestering and stocking CO2 in the living tissues of plants. However, continuous deforestation processes decreases its capacity to supply GCRES, especially in tropical forests which have high potential to provide the service and suffer strong pressure due to agroindustrial development. Brazilian Atlantic landscapes are examples of this condition, especially in the state of São Paulo, where natural vegetation was primarily converted into cattle pastures and forestry. Assessing and managing ecosystem services stocks and flows in spatially heterogeneous landscapes is one of the major challenges of landscape sustainability science. In this context, our objective is to evaluate the studies on the ecological valuation of GCRES in tropical forest and to analyse the supply of this service in Atlantic landscapes pressured by livestock activity. Initially, we investigated the trends and gaps that involve the biophysical attributes of GCRES in tropical and subtropical forest at a pan-tropical scale through a systematic review of the literature on the subject in the last 20 years, according to a qualitative exploratory approach. We found that (1) estimates of carbon stock from forests show high variability; (2) the most recurrent factors that influence on GCRES are land use and species richness; and (3) GCRES has a greater number of synergy relations with other SEs compared to trade-off relations. Secondly, we analysed the supply of the regulation service in Atlantic landscapes of the Paraiba do Sul Valley (SP, BR), considering the process of replacing native forest by pasturelands. We collected field data to calculate pasture and forest fragments aboveground biomass at different successional stages, and transformed these data into carbon stocks. This data subsidized the calculations of GCRES supply for 16 landscapes that had different proportions of forest and pasture areas. We also evaluated the influence of landscape configuration on forest remnants biomass production. We found carbon stock values of 16.9 ± 7.25 MgC ha-1 in initial forest, 34.8 ± 12.05 MgC ha-1 in intermediate-advanced forest and 0.53 ± 0.26 MgC ha-1 in cattle pastures. We identified that the distance to the nearest fragment decreases the early-stage forest biomass, while the average area of fragments located within a radius of 500 m around the sampled fragment increases the intermediate-advanced stage forest biomass. We highlight the fact that the evaluated landscapes with more than 40% of forested area have a differentiated contribution to the SERCG supply due to the increase in number and area of intermediate-advanced stage forest fragments. In spite of the contrast between the contribution of small fragments in the early stages and those of more advanced stage, the presence of the former implies a greater supply of SERCG at the landscape scale. In addition, the conservation of these fragments would not only influence the supply of the climate regulation service, but also the supply of other services with which it has synergistic relations