Alien plant invasion success can be inhibited by two key biotic factors:native herbivores and plant diversity.However,few studies have experimentally tested whether these factors interact to synergistically resist inv...Alien plant invasion success can be inhibited by two key biotic factors:native herbivores and plant diversity.However,few studies have experimentally tested whether these factors interact to synergistically resist invasion success,especially factoring in changing global environments(e.g.nutrient enrichment).Here we tested how the synergy between native herbivores and plant diversity affects alien plant invasion success in various nutrient conditions.For this purpose,we exposed alien plant species in potmesocosms to different levels of native plant diversity(4 vs.8 species),native generalist herbivores,and high and low soil nutrient levels.We found that generalist herbivores preferred alien plants to native plants,inhibiting invasion success in a native community.This inhibition was amplified by highly diverse native communities.Further,the amplified effect between herbivory and native plant diversity was independent of nutrient conditions.Our results suggest that a higher diversity of native communities can strengthen the resistance of native generalist herbivores to alien plant invasions by enhancing herbivory tolerance.The synergistic effect remains in force in nutrient-enriched habitats that are always invaded by alien plant species.Our results shed light on the effective control of plant invasions using multi-trophic means,even in the face of future global changes.展开更多
Invasive alien species （IAS） are considered as an overlooked forest resources in Nepal, despite its rapid expansion is considered as one of the main drivers of Nepal＇s forest degradation and deforestation. In this ...Invasive alien species （IAS） are considered as an overlooked forest resources in Nepal, despite its rapid expansion is considered as one of the main drivers of Nepal＇s forest degradation and deforestation. In this study, stratified systematic sampling, with nested circular plots of 500 m2, was performed in Sindhupalchowk to find out whether the removal of IAS contributes for an increase in plant diversity, Interaction with more than 310 entrepreneurs was carded to investigate the economic benefits in terms of income and employment of converting IAS into charcoal through pyrolysis in ＂bio-energy kilns＂. The study showed a higher Shannon-Weiner plant diversity index at regeneration level in IAS removed area （2.43） than that in control （1.95）. Similarly, the number of seedlings and saplings was significantly higher （P 〈 0.05） in the treatment block than the number of trees in the control one. Also, the pyrolysis of 7,500 million tons （MT） of IAS in bio-energy kilns produced 1,500 MT of charcoal powder which generated a total additional income of Nepali Rupees （NRs.） 18,900,000 to 1,050 poor and disadvantaged people in ! 6 districts of Terai and Midhills. In spite of that, some policy hurdles, such as charcoal transportation, were observed at the operational level. It is suggested that the plant diversity could be increased through the removal of IAS, and considerable economic benefits could be achieved if charcoal is substantially produced and utilized.展开更多
Aims Within a habitat of multiple plant species,increased resource availabilities and altered species abundances following disturbances create opportunities for exotic species to successfully establish and subsequentl...Aims Within a habitat of multiple plant species,increased resource availabilities and altered species abundances following disturbances create opportunities for exotic species to successfully establish and subsequently naturalize into its non-native environment.Such post-disturbance changes in abiotic and biotic environments may also promote a naturalized exotic species(or invading species)to become invasive through rapid colonization of the habitat sites by reducing the extent and size of resident plant species.By combining species life history traits with that of the disturbance-induced changes in habitat characteristics,we aimed to determine those interacting factors and associated mechanism allowing an exotic invasion to start off.Methods We used a modified version of the classic competition–colonization(CC)model which was formulated first by Hastings(1980)and studied later by Tilman(1994)to explain spatial coexistence of multiple species.Within this model framework,recruitment-limited spatial competition has explicitly been linked with interspecific resource competition without altering the basic assumptions and structure of the original CC model.Important findings The model results showed that at a constant rate of resource supply,invading species can stably coexist with native species via trade-offs between species competitive ability and colonizing ability.On the other hand,the model predicted that with a fluctuating resource condition,invading species can successfully invade a habitat following continuous reductions in the size and extent of native species.Whether or not invading species holds competitive superiority over the native species for limiting resource,we showed that there exists a range of variation in available resource that allows an exotic invasion to start off in post-disturbance habitat.The associated disturbance-induced mechanism promoting invading species to become invasive has been identified.It states that occurrences of disturbances such as fire or clear-cutting influence variation in resource availability,and in addition open up many vacant microsites;given these disturbance-induced changes,invading species with a higher rate of propagule production and with a higher survival rate of adults particularly in low-resource condition recruits microsites at faster rate relative to native competitor species,and with a given range of variation in resource availabilities,it maintains continued expansions following reductions in size and extent of native species.Moreover,we identified those interacting factors and their specific roles that drive this mechanism.These factors include propagule supply,variable resource level and vacant microsite availability.Increased availability of vacant microsites following disturbances creates an opportunity for rapid colonization.Given this opportunity,higher number of propagules supplied by the invading species enhances the rate of colonization success,whereas the resource variation within a range of given thresholds maintains enhanced colonization rate of the invading species while it depresses native competitor species.Owing to the each factor’s invasion regulatory ability,controlling one or all of them may have strong negative impact on the occurrence of exotic invasion.展开更多
基金supported by Postdoctoral Funding from Jilin Province to Liping Shan(2020000147).
文摘Alien plant invasion success can be inhibited by two key biotic factors:native herbivores and plant diversity.However,few studies have experimentally tested whether these factors interact to synergistically resist invasion success,especially factoring in changing global environments(e.g.nutrient enrichment).Here we tested how the synergy between native herbivores and plant diversity affects alien plant invasion success in various nutrient conditions.For this purpose,we exposed alien plant species in potmesocosms to different levels of native plant diversity(4 vs.8 species),native generalist herbivores,and high and low soil nutrient levels.We found that generalist herbivores preferred alien plants to native plants,inhibiting invasion success in a native community.This inhibition was amplified by highly diverse native communities.Further,the amplified effect between herbivory and native plant diversity was independent of nutrient conditions.Our results suggest that a higher diversity of native communities can strengthen the resistance of native generalist herbivores to alien plant invasions by enhancing herbivory tolerance.The synergistic effect remains in force in nutrient-enriched habitats that are always invaded by alien plant species.Our results shed light on the effective control of plant invasions using multi-trophic means,even in the face of future global changes.
文摘Invasive alien species （IAS） are considered as an overlooked forest resources in Nepal, despite its rapid expansion is considered as one of the main drivers of Nepal＇s forest degradation and deforestation. In this study, stratified systematic sampling, with nested circular plots of 500 m2, was performed in Sindhupalchowk to find out whether the removal of IAS contributes for an increase in plant diversity, Interaction with more than 310 entrepreneurs was carded to investigate the economic benefits in terms of income and employment of converting IAS into charcoal through pyrolysis in ＂bio-energy kilns＂. The study showed a higher Shannon-Weiner plant diversity index at regeneration level in IAS removed area （2.43） than that in control （1.95）. Similarly, the number of seedlings and saplings was significantly higher （P 〈 0.05） in the treatment block than the number of trees in the control one. Also, the pyrolysis of 7,500 million tons （MT） of IAS in bio-energy kilns produced 1,500 MT of charcoal powder which generated a total additional income of Nepali Rupees （NRs.） 18,900,000 to 1,050 poor and disadvantaged people in ! 6 districts of Terai and Midhills. In spite of that, some policy hurdles, such as charcoal transportation, were observed at the operational level. It is suggested that the plant diversity could be increased through the removal of IAS, and considerable economic benefits could be achieved if charcoal is substantially produced and utilized.
基金US National Science Foundation’s Biocomplexity Program(DEB-0421530)Long Term Ecological Research Program(Sevilleta)(DEB-0620482)and the University of California Agricultural Experiment Station。
文摘Aims Within a habitat of multiple plant species,increased resource availabilities and altered species abundances following disturbances create opportunities for exotic species to successfully establish and subsequently naturalize into its non-native environment.Such post-disturbance changes in abiotic and biotic environments may also promote a naturalized exotic species(or invading species)to become invasive through rapid colonization of the habitat sites by reducing the extent and size of resident plant species.By combining species life history traits with that of the disturbance-induced changes in habitat characteristics,we aimed to determine those interacting factors and associated mechanism allowing an exotic invasion to start off.Methods We used a modified version of the classic competition–colonization(CC)model which was formulated first by Hastings(1980)and studied later by Tilman(1994)to explain spatial coexistence of multiple species.Within this model framework,recruitment-limited spatial competition has explicitly been linked with interspecific resource competition without altering the basic assumptions and structure of the original CC model.Important findings The model results showed that at a constant rate of resource supply,invading species can stably coexist with native species via trade-offs between species competitive ability and colonizing ability.On the other hand,the model predicted that with a fluctuating resource condition,invading species can successfully invade a habitat following continuous reductions in the size and extent of native species.Whether or not invading species holds competitive superiority over the native species for limiting resource,we showed that there exists a range of variation in available resource that allows an exotic invasion to start off in post-disturbance habitat.The associated disturbance-induced mechanism promoting invading species to become invasive has been identified.It states that occurrences of disturbances such as fire or clear-cutting influence variation in resource availability,and in addition open up many vacant microsites;given these disturbance-induced changes,invading species with a higher rate of propagule production and with a higher survival rate of adults particularly in low-resource condition recruits microsites at faster rate relative to native competitor species,and with a given range of variation in resource availabilities,it maintains continued expansions following reductions in size and extent of native species.Moreover,we identified those interacting factors and their specific roles that drive this mechanism.These factors include propagule supply,variable resource level and vacant microsite availability.Increased availability of vacant microsites following disturbances creates an opportunity for rapid colonization.Given this opportunity,higher number of propagules supplied by the invading species enhances the rate of colonization success,whereas the resource variation within a range of given thresholds maintains enhanced colonization rate of the invading species while it depresses native competitor species.Owing to the each factor’s invasion regulatory ability,controlling one or all of them may have strong negative impact on the occurrence of exotic invasion.
