Advancing environmentally explicit structured population models of plants

Abstract

Summary The relationship between the performance of individuals and the surrounding environment is fundamental in ecology and evolutionary biology. Assessing how abiotic and biotic environmental factors influence demographic processes is necessary to understand and predict population dynamics, as well as species distributions and abundances. We searched the literature for studies that have linked abiotic and biotic environmental factors to vital rates and, using structured demographic models, population growth rates of plants. We found 136 studies that had examined the environmental drivers of plant demography. The number of studies has been increasing rapidly in recent years. Based on the reviewed studies, we identify and discuss several major gaps in our knowledge of environmentally driven demography of plants. We argue that some drivers may have been underexplored and that the full potential of spatially and temporally replicated studies may not have been realized. We also stress the need to employ relevant statistical methods and experiments to correctly identify drivers. Moreover, assessments of the relationship between drivers and vital rates need to consider interactive, nonlinear and indirect effects, as well as effects of intraspecific density dependence. Synthesis. Much progress has already been made by using structured population models to link the performance of individuals to the surrounding environment. However, by improving the design and analyses of future studies, we can substantially increase our ability to predict changes in plant population dynamics, abundances and distributions in response to changes in specific environmental drivers. Future environmentally explicit demographic models should also address how genetic changes prompted by selection imposed by environmental changes will alter population trajectories in the face of continued environmental change and investigate the reciprocal feedback between plants and their biotic drivers.

Environmental drivers of demographic variation across the global geographical range of 26 plant species

“…Leucadendron muirii in our study; but see also Ehrlén et al . ). Furthermore, we expect that certain counter‐intuitive responses (e.g.…”

“…Analyses of demographic responses to environmental variation thus need to account for such potentially confounding effects of intraspecific density dependence (Ehrlén & Morris ; Ehrlén et al . ). Additionally, analysing the range‐wide effects of intraspecific density is important since the strength and shape of density dependence can profoundly affect range dynamics (Cabral & Schurr ).…”

Quantifying how short‐term environmental variation leads to long‐term demographic responses to climate change

“…; Ehrlén et al . ) and in response to climate change (Morris et al . ; Doak & Morris ; Jongejans et al .…”

Theoretical contributions to biological control success

“…At least 136 studies have measured and modeled the influence of abiotic and biotic drivers of plant demography and population dynamics, but 71% of these studies examined only one driver. Of 181 cases (the number of cases 181 exceeds the number of studies 136 because some studies included more than one driver type) herbivory has been examined in 26%, disturbance in 25%, competition in 16%, climatic factors in 15%, other abiotic factors in 12%, mutualists in 5%, and pathogens in 1% (Ehrlen et al 2015). Our study of the ragwort system appears to be the only case where the independent and interacting effects of environmental drivers of disturbance, plant competition, herbivores (two species in this case) on plant demography and population growth have been examined together using a field experiment.…”