In: Biological Invasions, 2008, vol. 10, no. 6, p. 859-874
Practitioners of classical biological control of invasive weeds are confronted with a dual expectation: to achieve successful control of plant invaders and to avoid damage to nontarget plants and adverse indirect effects. In this paper we discuss key issues that we consider to be crucial for a safe, efficient, and successful classical biological control project, and that have also caused some...
|
In: Ecology, 2008, vol. 89, no. 2, p. 407–417
The “evolution of increased competitive ability” (EICA) hypothesis proposes that escape from natural enemies, e.g., after transcontinental introductions, alters the selection regime because costly defenses no longer enhance fitness. Such an evolutionary loss of defenses enables resources to be directed toward growth or other traits improving performance. We tested the EICA hypothesis in a...
|
In: Ecology, 2007, vol. 88, no. 2, p. 424–433
Evolutionary theory suggests that divergent natural selection in heterogeneous environments can result in locally adapted plant genotypes. To understand local adaptation it is important to study the ecological factors responsible for divergent selection. At a continental scale, variation in climate can be important while at a local scale soil properties could also play a role. We designed an...
|
In: Plant Ecology, 2007, vol. 190, no. 2, p. 233-243
The ability of weeds to form a seed bank is important for their population dynamics and management because it provides a refuge enabling reinvasion after established target plants have died. However, knowledge of the differential seed behaviour of individual species over multiple years and varying environmental conditions is surprisingly rare but necessary for effective control of diverse...
|
In: Oecologia, 2007, vol. 152, no. 2, p. 265-273
Current conceptual models predict that an increase in stress shifts interactions between plants from competitive to facilitative; hence, facilitation is expected to gain in ecological importance with increasing stress. Little is known about how facilitative interactions between plants change with increasing biotic stress, such as that incurred by consumer pressure or herbivory (i.e....
|
In: Ecology Letters, 2007, vol. 10, no. 8, p. 701-709
Niche-based models calibrated in the native range by relating species observations to climatic variables are commonly used to predict the potential spatial extent of species’ invasion. This climate matching approach relies on the assumption that invasive species conserve their climatic niche in the invaded ranges. We test this assumption by analysing the climatic niche spaces of Spotted...
|
In: Forest Ecology and Management, 2006, vol. 237, no. (1-3), p. 471-477
In wood pastures spatial associations of tree saplings with nurse structures such as unpalatable plants are generally explained as associational resistance; i.e. reduced herbivory by association with a defended neighbour. However, these associations may result from other underlying processes that occur at the seed stage. Here we tested whether the observed associations between...
|
In: Ecography, 2006, vol. Volume 29, p. 541-548
Traditionally managed mountain grasslands in the Alps are species-rich ecosystems that developed during centuries of livestock grazing. However, changes in land use including fertilisation of well accessible pastures and gradual abandonment of remote sites are increasingly threatening this diversity. In five regions of the Swiss and French Alps we assessed the relationship between land use, soil...
|
In: Journal of Ecology, 2006, vol. 94, p. 1130-1142
1 Adaptation of plant populations to local environments has been shown in many species but local adaptation is not always apparent and spatial scales of differentiation are not well known. In a reciprocal transplant experiment we tested whether: (i) three widespread grassland species are locally adapted at a European scale; (ii) detection of local adaptation depends on competition with the...
|
In: Journal of Vegetation Science, 2005, vol. 16, no. 2, p. 209-214
Question: Are tree saplings in wooded pastures spatially associated with specific nurse structures or plants that facili-tate tree sapling survival? Location: Wooded pastures in the Jura Mountains, Switzer-land. Methods: In two sites, 73 km apart, we sampled 294 plots of4 m², systematically distributed on 1 ha. We recorded number and height of all established Picea abies...
|
