abstract one basic method of improving rangelands in a country is the use of native as well as exotic species of plants adaptable. among the but introduced species, atriplex canescens has been introduced in many rangelands, but it is important and necessary to consider it’s effects on native species. in the current study the effect of chemical competition (allelopathy) of atriplex canescens on ...

Seed dispersal is a fundamental process in plant ecology and is of critical importance for the restoration of tropical communities. The lands of the Cabo Rojo National Wildlife Refuge (CRNWR), formerly under agriculture, were abandoned in the 1970s and colonized mainly by non-native tree species of degraded pastures. Here we described the seed rain under the most common native and non-native tr...

Old fields are diverse forb-dominated ecosystems transitioning into woody-dominated forested ecosystems. However, the susceptibility of old fields to high levels of plant invasion can lead to the co-occurrence of multiple non-native invasive plant species at the fine-scale of plant neighborhoods, which can alter native species co-occurrence patterns and successional trajectories into forest com...

INTRODUCTION While the literature is replete with studies of the toxic potency of pentachlorophenol (PCP), site-specific criteria for native aquatic species that can be used in ecological risk assessments has been lacking and application of toxicity information for non-native species is controversial. MATERIALS AND METHODS In the present study, acute and chronic toxicities of PCP to six aquat...

Although native enemies in an exotic species' new range are considered to affect its ability to invade, few studies have evaluated predation pressures from native enemies on exotic species in their new range. The exotic prey naiveté hypothesis (EPNH) states that exotic species may be at a disadvantage because of its naïveté towards native enemies and, therefore, may suffer higher predation pres...

An explanation for successful invasion is that invasive alien species sustain less pressure from natural enemies than co-occurring native species. Using meta-analysis, we examined whether invasive species: (1) incur less damage, (2) exhibit better performance in the presence of enemies, and (3) tolerate damage more than native species. Invasive alien species did not incur less damage than nativ...

Mountain environments are currently among the ecosystems least invaded by non-native species; however, mountains are increasingly under threat of non-native plant invasion. The slow pace of exotic plant invasions in mountain ecosystems is likely due to a combination of low anthropogenic disturbances, low propagule supply, and extreme/steep environmental gradients. The importance of any one of t...

3 Corresponding author: [email protected]; 828-667-5261 ext. 118; Fax: 828-667-9097 ABSTRACT: Invasive, non-native plants threaten forest ecosystems by reducing native plant species richness and potentially altering ecosystem processes. Seed dispersal is critical for successful invasion and range expansion by non-native plants; dispersal is likely to be enhanced if they can successfully comp...

The aim was to assess patterns of plant diversity in response to elevation and disturbance in a tropical mountain. The study area was located in north-central portion of the Eastern Cordillera of the Ecuadorian Andes, on a road from 1,150 m a.s.l. (Osayacu) to 4,000 (Papallacta). Along a mountain road spanning a wide altitudinal gradient, at 20 elevations we sampled three plots: one at the road...