RESUMEN
Recently, two approaches to account for ecological differences in community composition have been developed: one based on trait differences (functional diversity) and another based on evolutionary history (phylogenetic diversity). Combining them allows an integrated view of processes structuring communities. The North Adriatic Karst is covered by species-rich grasslands, but land abandonment has resulted in replacement by woodlands. This creates a successional gradient along which environmental conditions may change, and different community assembly rules may apply. We sampled 56 plant communities in the Karst and used functional-phylogenetic distances to assess assembly along a successional gradient, from grasslands to shrublands and woodlands. We found 146 species, for which we measured functional traits and built a phylogenetic tree. The three successional stages were floristically different, with grasslands having species that are typical of harsher soil conditions and woodlands with species preferring milder soil conditions. All communities had higher functional than phylogenetic distances, implying that closely related species tended to be phenotypically dissimilar. When more importance was given to functional distances, most grasslands and some shrublands were underdispersed; when more importance was given to phylogenetic distances, only one grassland was underdispersed and one woodland was overdispersed. Combining functional and phylogenetic distances provided us with better estimates of ecological differences in a successional gradient, where environmental filters seem to be the dominant force in early stages and competitive exclusion becomes more important in later stages. Taking into account that sucessional stages are assembled by different rules is essential to predicting their behaviour under future environmental scenarios.
Asunto(s)
Bosques , Pradera , Filogenia , Plantas , Evolución Biológica , Ecología , Ecosistema , Eslovenia , Suelo , ÁrbolesRESUMEN
A habitat transition model, based on the correlation between individual habitats and micro-elevation intervals, showed substantial changes in the future spatial distributions of coastal habitats. The research was performed within two protected areas in Slovenia: Secovlje Salina Nature Park and Skocjan Inlet Nature Reserve. Shifts between habitats will occur, but a general decline of 42 % for all Natura 2000 habitats is projected by 2060, according to local or global (IPCC AR4) sea level rise predictions. Three different countermeasures for the long-term conservation of targeted habitat types were proposed. The most "natural" is displacement of coastal habitats using buffer zones (1) were available. Another solution is construction of artificial islets, made of locally dredged material (2); a feasible solution in both protected areas. Twenty-two islets and a dried salt pan zone at the desired elevations suitable for those habitats that have been projected to decease in area would offer an additional 10 ha in the Secovlje Salina. Twenty-one islets and two peninsulas at two different micro-altitudes would ensure the survival of 13 ha of three different habitats. In the area of Secovlje Salina, abandoned salt pans could be terrestrialized by using permanent, artificial sea barriers, in a manner close to poldering (3). By using this countermeasure, another 32 ha of targeted habitat could be preserved. It can be concluded that, for each coastal area, where wetland habitats will shrink, strategic plans involving any of the three solutions should be prepared well in advance. The specific examples provided might facilitate adaptive management of coastal wetlands in general.
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Cambio Climático , Ecosistema , Modelos Teóricos , Humedales , Altitud , Bahías , Agua de Mar , EsloveniaRESUMEN
State boundaries limit human contacts in a homogenous context of a landscape and its natural features, including plants. After nine centuries of separation, finally the two territories in Slovenia share the same political history. In this paper we tried to answer the question to which extent the past political borders, geographical and cultural drivers affect today's traditional knowledge on wild plants use of Slovenians, living unified in the same political entity. Data were collected using 60 in-depth semi-structured interviews, from March to August 2019, in two municipalities: Komen at Karst and Izola in Istria concerning food, medicinal, economic use, and local customs. The results indicate a quite large divergence in ethnobotanical and ecological knowledge between the two studied areas. In the Komen area, many people still use wild plants daily for various purposes (Taraxacum officinale, Melissa officinalis, Urtica dioica, Cornus mas, and Sambucus nigra). In contrast, this is limited to fewer people in the Izola area and mainly to seasonal use of specific plants (Asparagus acutifolius, Rosa canina, Salvia officinalis, Foeniculum vulgare and Rubus caesius). Unusual for the Mediterranean is the use of young shoots of Clematis vitalba, in the Izola area prepared as omelettes. We can assume that these differences are partly due to minor differences in climatic conditions and partly due to the influence of different cultures and cuisines. In the first place, the impact of Austro-Hungarian eating habits and cuisine can be seen on the area around Komen. Moreover, temporal "layers of knowledge" across the time scale are additionally mixed by the immigration of people from other parts of Slovenia or abroad, or with the influence of local herbal specialists. At last, we conclude Komen area knowledge is alive and homogeneous, and more connected to their local identity.
RESUMEN
Political ideologies, policies and economy affect land use which in turn may affect biodiversity patterns and future conservation targets. However, few studies have investigated biodiversity in landscapes with similar physical properties but governed by different political systems. Here we investigate land use and biodiversity patterns, and number and composition of birds and plants, in the borderland of Austria, Slovenia and Hungary. It is a physically uniform landscape but managed differently during the last 70 years as a consequence of the political "map" of Europe after World War I and II. We used a historical map from 1910 and satellite data to delineate land use within three 10-kilometre transects starting from the point where the three countries meet. There was a clear difference between countries detectable in current biodiversity patterns, which relates to land use history. Mobile species richness was associated with current land use whereas diversity of sessile species was more associated with past land use. Heterogeneous landscapes were positively and forest cover was negatively correlated to bird species richness. Our results provide insights into why landscape history is important to understand present and future biodiversity patterns, which is crucial for designing policies and conservation strategies across the world.
Asunto(s)
Biodiversidad , Aves , Plantas , Sistemas Políticos , Agricultura , Animales , Conservación de los Recursos Naturales , Ecosistema , Europa (Continente) , Geografía , Historia del Siglo XX , Densidad de Población , Dinámica Poblacional , Primera Guerra Mundial , Segunda Guerra MundialRESUMEN
Stomatal density, leaf conductance and water relations can be affected by an increase in the concentration of atmospheric CO2, and thus affect plant productivity. However, there is uncertainty about the effects of elevated CO2 on stomatal behaviour, water relations and plant productivity, owing to the lack of long-term experiments in representative natural ecosystems. In this work, variations in stomatal density and index, leaf water relations and plant biomass of semi-natural grassland communities were analysed under field conditions by comparing plants in three different experimental set-ups (natural CO2 springs, plastic tunnels and mini-FACE systems). Natural degassing vents continuously expose the surrounding vegetation to truly long-term elevated CO2 and can complement short-term manipulative experiments. Elevated CO2 concentration effects on stomata persist in the long term, though different species growing in the same environment show species-specific responses. The general decrease in stomatal conductance after exposure to elevated CO2 was not associated with clear changes in stomatal number on leaf surfaces. The hypothesis of long-term adaptive modifications to stomatal number and distribution of plants exposed to elevated CO2 was not supported by these experiments on grassland communities. Elastic cell wall properties were affected to some extent by elevated CO2. Above-ground biomass did not vary between CO2 treatments, leaf area index did not compensate for reduced stomatal conductance, and the root system had potentially greater soil exploration capacity. Considerable between-species variation in response to elevated CO2 may provide a mechanism for changing competitive interactions among plant species.