Knowledge from ecological sciences is an important reference for landscape design as Urban Green Spaces (UGS) play a critical role in the ecological protection of cities. There is an ongoing debate among ecologists on the value of exotic vegetation to ecosystem resilience and integrity, with authors arguing that in order for ecosystems to survive in future climates, exotic species with similar conditions in their current range must be considered. Others deem biodiversity vital for ecosystem functions and services, stating that most biodiversity losses are man-induced and should be addressed through the enhancement of native communities. Through a literature review, we confronted the arguments used in this debate, with the aim of conducting a comprehensive analysis of the potential of exotic and native vegetation in different aspects of the vegetation’s performance. The outcomes are important for the assessment of vegetation assemblages within UGS projects. Despite the strong arguments regarding their performative and adaptive capacity, we conclude that exotics pose significant ecological risks and have multiple negative impacts on ecosystem processes. Natives not only present high adaptive capacity, but also provide additional benefits for biodiversity, ecosystem integrity, and for people. In a broader framework, the literature demonstrates a preference for the use of native species in most situations.

In Portugal, some species are now considered invasive by law and have proliferated in recent years. Among these, Acacia dealbata stands out. This work investigated the behavior of this species, in order to characterize and evaluate its potential as raw material for biomass pellets production, while controlling its proliferation. It was found that A. dealbata has a large capacity for raw material supply, as cutting 2 ha resulted in about 140 tons of biomass. Thus, the attribution of a market value for this material could result in a reduction in the area occupied by the invasive species, once the demand for it increases, causing a pressure over the resource. This pressure on the species must be duly followed by other control measures, such as reducing the population and mitigating its proliferation. Laboratory tests have shown that both the raw material and the finished product are similar to those obtained with other species normally used for biomass pellet production, such as Pinus pinaster and Eucalyptus globulus. Thus, it can be concluded that there is a high potential for this species in the production of biomass pellets for energy, and that this may be an important contribution to controlling the proliferation of this invasive species.

Tourism activity has a very significant weight in the world economy, even being the main activity responsible for the export of many countries, in the form of providing services to foreign citizens. In mainland Portugal, the main tourist region is the Algarve, where beach tourism, known as sun and sea tourism, plays a decisive role. However, this activity also has its negative impacts. In the present work, a case study was analyzed, at Praia da Cova Redonda, located in the parish of Porches, in the municipality of Lagoa. Negative impacts on land use and occupation were identified, caused by the excessive presence of people, the introduction of invasive species and the artificial filling of beaches. At the end, a set of mitigating measures are presented that aim to ensure that the exploitation of natural resources can be maintained, but in a perspective of preservation and recovery of natural resources and biodiversity.

The occupation of a territory combines a set of variables which affect the development of the mode by which populations have been organized throughout history. How this occupation takes place demonstrates much of a territory’s past and shows how the populations managed to make the most out of the available resources. The region of Entre-Douro-e-Minho (Northern Portugal), similarly to what happens in other regions, such as Galicia (Northern Spain), Brittany (Northern France), or Ireland, presents a type of dispersed land use, with an alternation of urban, agriculture, and forest areas. On one hand, this proximity allows urban populations to come into contact with a rural environment. On the other hand, this proximity also causes a set of problems, namely those related to rural fires, which are now enhanced by climate change, and associated phenomena, such as heatwaves and the lack of precipitation. The present work analyzes the evolution of rural fires in 1975–2019, in the municipality of Guimarães (Northern Portugal), to understand how these events have been distributed over time and evolved in a climate change scenario. Based on the results and discussion presented, it can be concluded that there is an increasing trend in the occurrence of rural fires in the territory under study, and that this can also be associated to climate change, in the form of a gradual increment in temperature, particularly in the autumn months, and a decrease in rainfall. This situation is responsible for the increment of the risk caused by the proximity of the populations to forest and agricultural areas because rural fires can jeopardize the safety of people and goods.

Biological invasions can affect ecosystems in different ways. Invasive forest species, such as Acacia dealbata Link., affect forests’ productivity, because they compete directly with native species for access to light and nutrients, contributing to the loss of biodiversity. In this study, an area occupied by A. dealbata, located in Casal do Rei (Seia, Portugal) was studied to evaluate the influence of fire in the dispersion of this species, analyzing the historical occurrence of rural fires in the region, as well as through the determination of its annual biomass production and comparing its growth with other species using satellite images. The research shows a competitive advantage for A. dealbata, even when compared to species, such as Eucalyptus globulus and Pinus pinaster, which practically disappeared from the location under study after a significant fire occurred in 2005, while A. dealbata continued to thrive.

The recurrent rural fires that occur annually in Portugal have reached great proportions due to a lack of effective landscape management. Attempts to solve this problem led to the legal imposition to cut back the vegetation in the fuel management areas, which has had a negative effect on biodiversity. National legislation protects three native plant species (Quercus suber, Q. rotundifolia and Ilex aquifolium). European legislation, through the Habitats Directive, also identifies some plant species that require strict protection, although it leaves out several endemic and rare plants. In this work we aim to differentiate the types of shrub plant material and their pyrophilic behavior, since the physical and chemical characteristics of vegetation can enhance or inhibit the progression of fire. Thus, based on phytosociological science, specifically at the class level, the dynamics of potential climatophilous vegetation in Portugal are presented and the classes that should be prioritized for control are identified. Based on ecology, it was possible to identify morphological patterns of vegetation. In short, the genera targeted for control under the National Forest Fire Protection Plan belong to the furthest states from the mature potential of a forest, generally consisting of heliophile shrubs and typically growing in degraded soils. The shrub species to be valued belong to dynamic states closer to the mature potential, consisting mainly of broad-leaved shrubs and those growing in better-preserved soils.