Ecological Monographs最新文献

Climate change and the global spread of non-native species are two of the most significant threats to biodiversity and ecosystem function. Both these phenomena subject populations to novel conditions, either in space (species introductions) or in time (climate change), yet the role of adaptation in how populations respond to these rapid environmental shifts is poorly understood. We conducted a large-scale transcontinental common garden experiment using white clover (Trifolium repens, Fabaceae) to test whether adaptive evolution to spatiotemporal variation in climate could contribute to the ecological success of one of the most widespread plant species in the world. Individuals from 96 populations of Trifolium repens (white clover) from both its native (Europe) and introduced (North America) ranges were planted into four experimental common gardens located in northern (Uppsala, Sweden) and southern (Montpellier, France) Europe, and northern (Mississauga, Canada) and southern (Lafayette, USA) North America. We recorded plant sexual and clonal fitness in each common garden, and assessed whether the strength of local adaptation differed between the native and introduced ranges, and whether populations are rapidly adapting to climate change. Results show that local adaptation was only evident when populations were transplanted into common gardens located in the same range (native or introduced) from which they originated, and was driven by stronger selection (due to climatic factors rather than herbivory) at lower latitudes in both ranges. Our results indicate rapid local adaptation across a large latitudinal gradient in introduced T. repens populations, along with an associated adaptation cost when transplanted back into the native range. We also find evidence of an adaptation lag in the northern common garden in the introduced range, with plants from historically warmer climates exhibiting the greatest fitness. These findings support two major conclusions: (1) white clover can rapidly adapt to spatial variation in climate in its introduced range as well as its native range, and (2) despite rapid adaptation to novel environments, introduced white clover populations are not keeping pace with rapid climate change. Overall, our results provide insight into the role of adaptation in facilitating the ecological success of non-native species in a rapidly changing world.

Predicting the growth and maximum biomass (M_max) of woody plant communities (WPCs) remains a central challenge in terrestrial ecology due to the complex and heterogeneous nature of tree growth. While metabolic scaling theory (MST) provides a valuable conceptual framework, it remains limited in its ability to fully explain community-level growth or carbon dynamics. To address this limitation, we developed an iterative growth model for forests (IGMF), built upon an iterative growth framework grounded in MST's core principles and further incorporating the self-thinning effect. The IGMF and its extensions suggest that community-level growth, net primary productivity (NPP), and other key components of the carbon budget—including gross primary productivity, autotrophic respiration, organ turnover, and non-structural carbohydrate storage—may be approximated as functions of current biomass, biomass-specific maintenance respiration, stand age, or M_max. These relationships provide a basis for estimating the global M_max of WPCs during 2018–2020 at approximately 1440 ± 26 Pg (1 Pg = 1 × 10¹⁵ g), with an additional biomass potential of about 510 Pg under current conditions. However, machine learning projections suggest that this potential may decline by up to 246 Pg by 2100, primarily within evergreen broadleaf forests. Our analyses also indicate that species richness, by promoting functional convergence, can amplify the negative effects of temperature and precipitation seasonality on M_max. In contrast, warming in the Northern Hemisphere may favor M_max accumulation in open shrublands. Together, these results help to clarify the growth dynamics of WPCs and suggest a possible shift in the major contributors to terrestrial carbon sequestration—from forests to shrublands—under future climate scenarios.

Temperature and resources are fundamental factors that determine the ability of organisms to function and survive, while influencing their individual and population growth. Major bodies of ecological theory have emerged, largely independently, to address temperature and resource effects. It remains a pressing challenge to unite these ideas and determine the interactive effects of temperature and resources on ecological patterns and processes, and their consequences across ecological scales. Here, we propose a simple, physiologically motivated model capturing the interactive effects of temperature and resources (specifically, inorganic nutrients and light) on the growth of microbial ectotherms over multiple ecological scales. From this model we derive a set of key predictions. At the population level, we predict (1) interactive effects of resource limitation on thermal traits (parameters describing effects of temperature on growth), (2) consistent differences in the temperature sensitivity of auto- and heterotrophs, and (3) the existence of specific trade-offs between traits that determine the shape of thermal performance curves. At the community level, we derive predictions for (4) how limitation by nutrients and light can change the relationship between temperature and productivity. All four predictions are upheld, based on our analyses of a large compilation of laboratory data on microbial growth, as well as field experiments with marine phytoplankton communities. Collectively, our modeling framework provides a new way of thinking about the interplay between two fundamental aspects of life—temperature and resources—and how they constrain and structure ecological properties across scales. Providing links between population and community responses to simultaneous changes in abiotic factors is essential to anticipating the multifaceted effects of global change.