Functional trait trade‐off and species abundance: insights from a multi‐decadal study

Abstract

Phylogenetically informed trait comparisons across entire communities show promise in advancing community ecology. We use this approach to better understand the composition of a community of winter annual plants with multiple decades of monitoring and detailed morphological, phenological and physiological measurements. Previous research on this system revealed a physiological trade‐off among dominant species that accurately predicts population and community dynamics. Here we expanded our investigation to 51 species, representing 96% of individual plants recorded over 30 years, and analysed trait relationships in the context of species abundance and phylogenetic relationships. We found that the functional‐trait trade‐off scales to the entire community, albeit with diminished strength. It is strongest for dominant species and weakens as progressively rarer species are included. The trade‐off has been consistently expressed over three decades of environmental change despite some turnover in the identity of dominant species.

Simulated Photovoltaic Solar Panels Alter the Seed Bank Survival of Two Desert Annual Plant Species

“…Understanding seed banks has proven to be exceptionally challenging, rendering our knowledge of early life history traits incomplete across the plant kingdom [ 1 , 2 ]. Studies are needed to enumerate and predict changes in seed banks, particularly to ascertain if plant species’ or communities’ seed banks respond to environmental changes [ 2 , 3 , 4 , 5 , 6 , 7 , 8 ]. Studies of annual seed banks in deserts may be especially useful to study seed bank trait–environment interactions because these environments are characterized by extreme variability in temperature and precipitation [ 9 , 10 ]—variability that increasingly characterizes Earth’s environments.…”

“…Studies of seed banks of rare and common species in desert annual plant communities may aid an understanding of seed bank traits. For several reasons, desert annual plants are an established model system for seed bank studies: their aboveground life cycle stages are exceptionally fast, they are mostly surficial in the soil (≤2 cm depth), and their responses to changes in the environment often occur over short durations of time [ 8 , 22 , 23 , 24 , 25 , 26 ].…”

“…Fine-tuned environmental responsiveness of seed traits can elicit dramatic annual variation in aboveground abundance of taxonomic and functional groups, including across common and rare groups of species [ 36 , 37 ]. Some have posited that rare species may serve as pre-adapted replacement species within plant communities should climatic and/or environmental characteristics change, subsequently casting the ‘rare’ plant into a new role as ‘common’ [ 8 , 38 ]. Observations of rare species with relatively higher seed bank survival than common species within a single community may, in part, support this hypothesis.…”

“…We use a seed bank packet method to quantify in situ seed bank survival directly ( Figure 1 ) and present a complementary conceptual framework ( Figure 2 ). We use this framework to compare seed bank survival between the common and rare annual desert plant species [ 8 , 38 ] and to evaluate seed bank survival across microhabitats (shade, runoff) and control microhabitats that vary in soil moisture and light and emulate effects of PV solar energy infrastructure ( Figure 3 ). We interpret our findings both in the context of theory on rare and common species, including responses to changes in environmental conditions, and as they inform the study of annual plant responses to microhabitat variation needed to guide land-use planning and management decisions [ 47 ].…”

Functional Composition Changes of a Subtropical Monsoon Evergreen Broad-Leaved Forest Under Environmental Change

“…Climate changes have altered the physical environments (e.g., soil moisture, temperature, and water vapor pressure deficit) of plant communities and shifted community species composition due to the fact that different functional groups, plant genera, and species respond divergently to climate change [1][2][3][4][5]. Based on long-term monitoring forest plots, several recent studies reported that climate change, especially drought, induced community composition to be shifting towards more dry-tolerant individuals and genera in Central American forests [1,6], West African forests [7], Amazon forests [2,8], and some temperate forests [9].…”