TY - JOUR
T1 - Landscape-level persistence and distribution of alien feral crops linked to seed transport
AU - Meffin, Ross
AU - DUNCAN, Richard
AU - Hulme, Philip
N1 - Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2015/5/1
Y1 - 2015/5/1
N2 - To assess the biotic and abiotic drivers of feral crop persistence, the occurrence and size of alien Brassica populations across an agricultural landscape in Canterbury, New Zealand, were surveyed over three years. Measures related to propagule input and site conditions were recorded and their role in explaining population occurrence and persistence assessed through GLMs and proportional-hazard models. Many Brassica populations were transient, with about 60% of populations disappearing within two years. New populations were founded at a rate that compensated for those that disappeared, and were more likely to occur along transportation routes and near seed companies, suggesting they established from seed spillage. Larger populations and those growing where habitat conditions were similar to those in which Brassica are cultivated had higher probabilities of survival. Without anthropogenic seed input to found new populations, Brassica spp. are unlikely to persist in this landscape beyond ten years. To avoid overestimating the extent of naturalised populations over time it is important to account for local population extinctions. The abundance of feral crops that occur as casuals in the landscape, along with other aliens that are maintained by external seed inputs, could be controlled by managing propagule sources. In themselves, casual populations are unlikely to facilitate gene flow or act as sources of further population spread.
AB - To assess the biotic and abiotic drivers of feral crop persistence, the occurrence and size of alien Brassica populations across an agricultural landscape in Canterbury, New Zealand, were surveyed over three years. Measures related to propagule input and site conditions were recorded and their role in explaining population occurrence and persistence assessed through GLMs and proportional-hazard models. Many Brassica populations were transient, with about 60% of populations disappearing within two years. New populations were founded at a rate that compensated for those that disappeared, and were more likely to occur along transportation routes and near seed companies, suggesting they established from seed spillage. Larger populations and those growing where habitat conditions were similar to those in which Brassica are cultivated had higher probabilities of survival. Without anthropogenic seed input to found new populations, Brassica spp. are unlikely to persist in this landscape beyond ten years. To avoid overestimating the extent of naturalised populations over time it is important to account for local population extinctions. The abundance of feral crops that occur as casuals in the landscape, along with other aliens that are maintained by external seed inputs, could be controlled by managing propagule sources. In themselves, casual populations are unlikely to facilitate gene flow or act as sources of further population spread.
KW - Anthropogenic dispersal
KW - Exotic
KW - Feral crops
KW - Propagule pressure
KW - Roadside vegetation
KW - Survival analysis
KW - Weed
UR - http://www.scopus.com/inward/record.url?scp=84922821762&partnerID=8YFLogxK
U2 - 10.1016/j.agee.2015.01.024
DO - 10.1016/j.agee.2015.01.024
M3 - Article
SN - 0167-8809
VL - 203
SP - 119
EP - 126
JO - Agriculture, Ecosystems and Environment
JF - Agriculture, Ecosystems and Environment
IS - 3
ER -