Remnant population dynamics in the facultative biennial Carum carvi in fragmented semi-natural grasslands
2009 (English)In: Population Ecology, Vol. 51, 197-208 p.Article in journal (Refereed) Published
Transition matrix models were used to examine population dynamics in the facultative biennial Carum carvi L. in semi-natural grasslands, specifically to assess what life cycle stages that are important for population development and to evaluate effects of environmental stochasticity on population persistence and, hence, the ability to develop remnant populations.
The demographic studies were conducted over a four year period in three moderately grazed grasslands that differed in onset and duration of grazing. Experimental seed sowing was also conducted in disturbed and undisturbed plots in the populations. Deterministic and stochastic models yielded overall negative population growth (λ < 1) for the populations. λ was sensitive to transitions in the most frequent vegetative stage classes. Elasticity analysis indicated that a large proportion of population growth could be ascribed to stasis of individuals in the largest vegetative stage class. LTREs showed that also progression to larger stage classes was important in explaining between-population variation in λ. The expected time to extinction was in the order of several decades for the study populations. Seed sowing indicated that seedling establishment was limited by both seed and micro-site availability. The populations of C. carvi seem to be able to persist for a rather long time in moderately grazed semi-natural grasslands, even in cases where populations are destined to go extinct. The results thus indicate that “biennials” are able to maintain remnant populations in managed semi-natural grasslands.
Place, publisher, year, edition, pages
2009. Vol. 51, 197-208 p.
Demography • Elasticity • LTREs • Matrix models • Short-lived monocarp • Sweden
IdentifiersURN: urn:nbn:se:su:diva-15173DOI: doi:10.1007/s10144-008-0096-2ISI: 000261986700021OAI: oai:DiVA.org:su-15173DiVA: diva2:181693