Ulrich Deil

Informing about climate change and invasive species: how the presentation of information affects perception of risk, emotions, and learning

Environmental issues such as climate change are becoming ever more important in today’s societies and politics. Information is spread by the media, for example, via the Internet or information brochures, employing different representational styles (e.g. sensational vs. neutral styles, emphasis of human vs. natural causes). We investigated the effects of such differences in presentation when informing about local impacts of climate change – more specifically about invasive species – on perceived risk, emotions, and learning. Seventy-two students at a German university read five brochures about the local effects of climate change and invasive species. They rated their perceived risk and emotions and worked on learning outcome tests. As expected, the sensational style led to higher perceived risk and stronger negative emotions than the neutral style. In addition, our results reveal a potential dilemma for environmental education: while a sensational style enhanced general learning outcomes, it seemed to lead to quite a negative and one-sided view about climate change and invasive species.

The vegetation of seasonal wetlands in extratropical and orotropical South America

Until now, the vegetation of seasonal wetlands in South America has only been studied on local to regional scales. A synoptic view is lacking and the distribution of vegetation types remains unknown. Hence we attempt here to detect fl oristic patterns on the spatial dimension of the subcontinent and to identify the environmental factors behind them. All plot-related fl oristic data (phytosociological relevés) available to us were collected and stored in a TURBOVEG-database. The study area included both extratropical South America (austral-temperate and subantarctic climatic zones) and the orotropical biome of the Andean Highlands, because the amphibic habitats in the two areas have some taxa in common. Tropical lowlands were more dissimilar and thus were excluded. In total we found 573 vegetation samples in 28 bibliographic sources, published between 1960 and 2008. To achieve a consistent nomenclature was a major problem, and the taxonomic treatment of a number of habitat specifi c taxa is obviously in need of improvement. Classifi cation and ordination were performed with the total data set as well as just the diagnostic taxa. The fl oristic structure was analysed using non-metric multidimensional scaling (nMDS) and procrustes rotation techniques to compare species combinations at the species and genus levels. The interpretation of the results is limited by the substantial fl oristic and ecological heterogeneity of the data (varying plot size, plots including an inundation gradient etc.) and by the spatially uneven distribution of the data. The classifi cation revealed a higher diversity of communities than expected: 11 clusters with precise species combinations, ecology and distribution emerged from the classifi cation: A) Plagiobothryo-Acaenion platyacanthae and B) Prat ion repentis are distributed in Southern Patagonia in seasonal lagoons, respectively on inundated turfs. Moorland pools and inundated bog hollows in hard cushion mires of the Andean belt have a number of genera in common, but separate on the species level into C) Muhlenbergia fastigiata-Distichlis humilis-communities in the semi-desert highlands of NW Argentina, D) Gentiana sedifolia-Carex bonplandii and GentianoOritrophion-communities in the Super-Páramo belt of Venezuela, E) the Lilaeopsion andinae in the altiplano extending from S Peru to NE Chile and NW Argentina, and F) Limosella-communities ranging from E Bolivia to Central Andean Peru. Lakeshores in the super-forest belt of the wet tropical Andes and in the mountainous parts of extratropical South America are colonized by the Crassuletal ia peduncularis-venezuelensis (cluster G), the amphibic zone of lakes in the temperate climate of Chile and Argentina by Littorel l ion austral isand Senecioni zosteraefol i i-Eleocharietal ia-communities (cluster H). The vegetation of vernal pools in Mediterranean Chile has been poorly studied until now, but some communities are recorded from the transition zone to temperate Chile. They are grouped in Juncion planifol i i (cluster I). Seasonal wetlands in fl ooded Pampa grassland of Argentina are characterized by the Ludwigia peploides-Luziola peruviana-communities (group J). Muddy river banks of River Paraná are colonized by the Lindernio dubiae-Mecardonietum (cluster K). Strong spatial patterns emerge on the continental scale, not only from vicinismus effects of the matrix vegetation surrounding the small-scale seasonal wetlands, but also for the habitat specifi c fl ora and vegetation. The main differentiating environmental factors on large scales are macroclimatic conditions and the trophic level of the substrate. Water depth, inundation duration and germination conditions in the amphibic ecophase result in a local zonation pattern. An azonal character of seasonal wetlands becomes obvious on the super-specifi c taxonomic rank from genera, that speciated within this environment and evolved geographical vicarious species with similar niches (e.g. Isoëtes, Limosella, Ranunculus, Hypsela, Oritrophium, Littorella, Lilaeopsis, Muhlenbeckia and Crassula).

Forest vegetation on sacred sites of the Tangier Peninsula (NW Morocco) – discussed in a SW-Mediterranean context

Forest stands on sacred sites can document climax or preclimax vegetation. However, little is known about the potential climax character of sacred sites in Morocco. We studied the vegetation of Muslim sacred sites and graveyards in rural regions of the Tangier Peninsula in Northwest Morocco. Sacred sites were chosen according to a pre-stratifi ed random sampling method, taking climatic and edaphic patterns into account. In tree stands of 68 sacred sites 140 phytosociological relevés were sampled and classifi ed. In an attempt to evaluate their degree of preservation, the best preserved holy forests were compared with reference data of similar forest communities, recorded mainly on non-sacred sites in southern Spain and Portugal, and northern Morocco and Algeria. The forested vegetation of sacred sites shows a great variety. Abiotic factors, such as substrate and bioclimate, and human interventions (grazing, fi re, a.o.) were found to be important differentiating factors. Besides well-conserved forests, a broad spectrum of degradation stages was documented. Most stands still shelter the original tree species combination, but vertical structure and fl oristic composition of the herb layer are strongly modifi ed. Processes related to anthropo-zoogenic pressure, like therophytization, ruderalisation and overaging of the tree layer occur despite religious taboos. Near-natural holy forests belong to various subtypes of the Teucrio baetici-Quercetum suberis and the Rusco hypophyll i-Quercetum cocciferae. In comparison to forests on non-sacred sites, these holy forests are very well preserved, as is indicated by the presence of strict forest species of the Quercetal ia i l ic is and the Querco-Oleion sylvestr is , by transgressives of the Quercetal ia pubescentis , and by a high constancy and abundance of ombroand mesophilous taxa. Moreover, the comparison of phytosociological data from Morocco and Spain indicated an Ibero-Mauretanian distribution of several Quercus suber communities. In conclusion, sacred groves often seem to represent the potential natural vegetation. Exceptions are sacred groves with Wild Olive, which occur in an ecoregion where a thermomediterranean Quercus suber forest is considered to be the climax.

Amphibious Vegetation in the Afro-Alpine Belt and the Role of Cryoturbation in Creating Regeneration Niches

The wetland vegetation of the Afro-(sub)alpine belt, which is dominated by tussock grassland, has embedded in it ericaceous shrubs, Helichrysum cushions and Carex bogs, which constitute small microhabitats with annuals. A synopsis of these annual turfs is presented in a constancy table, based upon the available plot data (168 releves), sampled on the tops of the high volcanoes of East Africa (3500–4500 m altitude). The results are compared with similar vegetation types in the Ethiopian Highlands, Drakensberg Mts. and Marion Island (South Africa).

Vascular plant assemblages of ephemeral wetland vegetation along the Mediterranean-temperate gradient in Chile

Actualmente se conoce muy poco sobre la composicion floristica y la distribucion geografica de humedales temporales en Chile mediterraneo. Con el fin de llenar este vacio, se realizaron 73 inventarios floristicos en el gradiente mediterraneo- templado de Chile (31-44°S). Ademas, se llevo a cabo una busqueda bibliografica exhaustiva de inventarios fitosociologicos en publicaciones cientificas, incluyendo algunos inventarios de la parte argentina de la Cordillera de los Andes. Se obtuvo una matriz con 228 observaciones y 269 especies. Se aplico una clasificacion jerarquica para generar ensambles de co- ocurrencia. Dichos ensambles fueron comparados con grupos de especies diagnosticas definidas a priori, con formas de vida y tipos de origen (especies introducidas en Sudamerica vs especies nativas). Para determinar patrones de distribucion geografica y climatica, se extrajeron variables del modelo WorldClim y se aplicaron a un analisis de componentes principales (PCA). Segun la clasificacion jerarquica se determinaron siete ensambles de especies con una alta correspondencia a los grupos definidos a priori (P < 0,01), sin embargo con un nivel relativamente bajo de asociacion (indice V de Cramer = 0,49). En la vegetacion estudiada dominan las especies nativas sobre las introducidas, lo que sugiere un bajo riesgo de extincion por competencia con especies introducidas adaptadas a este tipo de ambientes. La forma de vida anual esta sobrerrepresentada en la mayoria de los ensambles. Pese al enorme gradiente de temperatura y precipitacion incluido en el rango de las muestras, los ensambles se distribuyen a lo largo de todo este gradiente, apoyando la hipotesis de azonalidad (indiferencia al macro-clima). Los ensambles definidos en este trabajo pueden ser potencialmente utilizados para posteriores clasificaciones supervisadas con el fin de definir tipos de comunidades vegetales en lagunas temporales.