Minimizing invasive potential of Miscanthus x giganteus grown for bioenergy: Identifying demographic thresholds for population growth and spread
Matlaga, DP; Davis, AS
| HERO ID | 5013451 |
|---|---|
| In Press | No |
| Year | 2013 |
| Title | Minimizing invasive potential of Miscanthus x giganteus grown for bioenergy: Identifying demographic thresholds for population growth and spread |
| Authors | Matlaga, DP; Davis, AS |
| Journal | Journal of Applied Ecology |
| Volume | 50 |
| Issue | 2 |
| Page Numbers | 479-487 |
| Abstract | Many species prioritized for bioenergy crop development possess traits associated with invasiveness, necessitating a priori efforts by ecologists to identify species or cultivars with minimal invasive potential. The grass Miscanthusxgiganteus Greef et Deu ex Hodkinson et Renvoize is a candidate for biomass production in the northern US maize belt, with both sterile and fertile varieties commercially available in the near future. Prior to widespread deployment, the invasive potential of both varieties must be quantified. Using M.xgiganteus demographic and seed dispersal data, we parameterized an age-/stage-structured integrodifference equation model to estimate potential spread rates of sterile and fertile M.xgiganteus. We identified thresholds for reproductive parameters, above which population numbers and space occupied are likely to increase. Our simulations considered lateral spread of M.xgiganteus but not dispersal of rhizome fragments. When clonal recruitment is absent, population growth rate for sterile M.xgiganteus is projected to be slightly <1 (=0 center dot 979), indicating gradual population decline over the long term. A sterile M.xgiganteus population may increase in numbers and space under certain conditions: annually rhizome sprouting must be >20% and rhizome production must be 1 per plant. The relatively slow spread rates (00 center dot 09myear1) estimated for sterile M.xgiganteus would not apply in scenarios where rhizomes were dispersed long distance. For a fertile M.xgiganteus genotype, even low rates of seed viability and survival, seedling survival and seed germination support rapidly expanding populations. Synthesis and applications. Spatial demographic models offer a powerful tool for quantifying risk of invasive spread by bioenergy crops. Our results suggest that sterile and fertile cultivars of M.xgiganteus have markedly different invasive potential and therefore should be considered separately in management and policy decisions. Feral populations of sterile M.xgiganteus would need to experience frequent and severe disturbance to pose a significant invasion risk, indicating that they should be grown well away from riparian areas prone to streambank scouring. In contrast, cultivars of M.xgiganteus bearing fertile seed may be very difficult, if not impossible, to contain. |
| Doi | 10.1111/1365-2664.12057 |
| Wosid | WOS:000316969300022 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |
| Keyword | bioenergy crop; integrodifference equation models; large statured invasive grasses; matrix model; risk assessment; spatial population dynamics |