Hence, knowledge of earthworm species associations and their interactions is important not only for an understanding of the functioning of soil systems and predicting the consequences of invasions of peregrine earthworms for native earthworm fauna, soil food web structure and functioning, but also for the structure and functioning of the aboveground food web.
While presenting a great conservation challenge, this also presents opportunities for the study of speciation and ecological consequences of invasions.
Assessing ecological and evolutionary consequences of invasions simultaneously may therefore be the most effective approach to study taxa with complex invasion histories.
Knowledge of the behavioral impacts resulting from nonlethal interspecific competition between native and nonnative species can, therefore, give insight into the mechanisms and consequences of invasions (reviewed in Chapple et al. 2012).
The steady increase in non-native plant introductions over time (Hulme et al. 2009) and the need to determine the consequences of invasions for native ecosystems has driven a significant increase in research on plant invasion impacts, particularly over the last decade (Pyšek and Richardson 2010).
Therefore, early detection and timely management is required to alleviate ecosystem consequences of invasion.
This paper describes some of the interactions between vegetation and water on rangelands and poses 3 questions that represent high-priority, emerging issues: 1) How do changes in woody plants affect water yield? 2) What are the ecohydrological consequences of invasion by exotic plants?
In addition, long-term studies of the consequences of invasion by native species can serve as valuable surrogates to understand the impacts of invasion by non-indigenous species on community structure and function under future climate scenarios.
Despite the pivotal long-term consequences of invasion for native food-webs, to date there are no experimental studies examining directly whether exotic plants are any more or less biochemically deterrent than native plants to native herbivores.
Not only do population genetic data provide valuable insight into the genetic consequences of invasion, they also provide information on movement pathways and invasion routes (Congdon et al. 1997; Suhr et al. 2010; Zepeda-Paulo et al. 2010) and overall invasion potential and pest status (Darling et al. 2008; Jiang et al. 2010).
