This thesis is aimed to better understanding the coupled social-ecological systems and their change over time in a holistic and relational way. It intends to show that productive rural activities are not necessarily incompatible with conservation of biodiversity, and that some of these activities, even when they are quite integrated with market economies, are indispensable to conserve the cultural landscapes that modern urban societies want to protect. This thesis also asks whether forest recoveries have a negative effect on water discharge from the catchments and on the biodiversity from open habitats at a local scale. It also explores the transformation of the countryside during the process of industrialization and urbanization to support the notion of historical interrelatedness and hybridity between the rural and the urban; and shows that suburbanization is the outcome of political struggles between different social groups resulting in uneven distribution of the costs and benefits of socioecological change. The Mediterranean is a particularly illuminating region for the aims of this research since it is considered a hotspot of global biodiversity which itself is a consequence of the integration between natural and human processes, besides being highly threatened because of the particular sensitivity of Mediterranean ecosystems to all drivers of global change. This thesis is focused in the Barcelona Metropolitan Region (Catalonia), one of the largest cities of Mediterranean Europe, more specifically in two mountain municipalities of the outer metropolitan ring: Olzinelles, in Montnegre Mountains, and Matadepera, in Sant Llorenç del Munt Mountains. The methodology combines elements from environmental history, political ecology and forest hydrology with the local ecological knowledge from peasants. The analysis of the productive system of Olzinelles and its historical roots (chapter 4) shows that several management practices, embedded in a particular institutional setting and worldview, allowed the social-ecological system to adapt to the changing external demand while keeping its capacity to supply food to the local community. The abandonment of such practices under a national-to-global process of modernization resulted in a decrease of species from fields, meadows and sparse forests. At the catchment scale (Olzinelles valley, chapter 3) it is concluded that the observed decrease in the water runoff may be attributed to a drier period rather than to the small afforestation experienced in the catchment. However, future studies should incorporate the variation of canopy cover given its potential role in rainfall interception and partitioning processes, and the great increase in canopy cover experienced in the catchment as a result of the abandonment of forest management practices. The analysis of Matadepera (chapter 5) shows that different visions of the future by different social groups (landowners vs. left-wing peasantry) collided in the process of suburbanization. The socioecological project promoted by ruling elites prevailed because they were able to control vital resources like land and water with the annihilation of the dissidence through prison, execution and psychological violence under the new Francoist regime that arose after the end of the Civil War in 1939. The discursive construction of a ‘natural scarcity’ of water helped to achieve spontaneous consent for controversial aspects of bringing water from the Llobregat River to allow the gentrification of the town. The thesis concludes that a suitable combination of different degrees of socioecological hybridity in the analysis may be suitable to understand the complex dynamics of land change and biodiversity conservation in a particular setting, as well as useful to overcome the strict conceptual and analytical separation between society and nature; city and countryside; conservation and development; and protected and non-protected areas.