Forest dynamics arise from the interplay of environmental drivers and disturbances with the demographic processes of recruitment, growth, and mortality, subsequently driving biomass and species composition. However, forest disturbances and subsequent recovery are shifting with global changes in climate and land use, altering these dynamics. Changes in environmental drivers, land use, and disturbance regimes are forcing forests toward younger, shorter stands. Rising carbon dioxide, acclimation, adaptation, and migration can influence these impacts. Recent developments in Earth system models support increasingly realistic simulations of vegetation dynamics. In parallel, emerging remote sensing datasets promise qualitatively new and more abundant data on the underlying processes and consequences for vegetation structure. When combined, these advances hold promise for improving the scientific understanding of changes in vegetation demographics and disturbances.

Earth system models must predict forest responses to global change in order to simulate future global climate, hydrology, and ecosystem dynamics. These models are increasingly adopting vegetation demographic approaches that explicitly represent tree growth, mortality, and recruitment, enabling advances in the projection of forest vulnerability and resilience, as well as evaluation with field data. To date, simulation of regeneration processes has received far less attention than simulation of processes that affect growth and mortality, in spite of their critical role maintaining forest structure, facilitating turnover in forest composition over space and time, enabling recovery from disturbance, and regulating climate-driven range shifts. Our critical review of regeneration process representations within current Earth system vegetation demographic models reveals the need to improve parameter values and algorithms for reproductive allocation, dispersal, seed survival and germination, environmental filtering in the seedling layer, and tree regeneration strategies adapted to wind, fire, and anthropogenic disturbance regimes. These improvements require synthesis of existing data, specific field datacollection protocols, and novel model algorithms compatible with global-scale simulations. Vegetation demographic models offer the opportunity to more fully integrate ecological understanding into Earth system prediction; regeneration processes need to be a critical part of the effort.

1. After a century of fire suppression and accumulating fuel loads in North American forests, prescribed burns are increasingly used to prevent conditions leading to catastrophic megafire. There is widespread evidence that prescribed fire was used by Indigenous communities to manage natural and cultural resources for thousands of years. Wildlife habitat is an example of an ecological response that was actively managed with prescribed burns by Indigenous American peoples and is an important factor in western US forest management planning, restoration and climate resilience efforts.2. We analysed the effects of modern prescribed burns informed by traditional ecological knowledge (TEK) on the predicted change in elk winter habitat in Karuk aboriginal territory in Northern California between 2013 and 2018 using species distribution and simultaneous autoregressive modelling techniques. Burn types most closely resembling Karuk traditional practices, specificallythose incorporating multiple-year broadcast burns, had significant positive effects on elk winter habitat suitability. Conversely, concentrated burns focused solely on reducing fuel loads had significant negative effects on elk winter habitat suitability. However, areas where these fuel-reduction burns were combined with multiple years of broadcast burns featured the highest increases in habitat. Synthesis and applications.Our results suggest that transitioning to prescribed burns that more closely follow Karuk traditional ecological knowledge will promote elk habitat in the region. This would be best achieved through continuing to work closely with Indigenous representatives to plan and implement cultural fire prescriptions on a landscape scale, a trend we posit would benefit environmental management efforts across the globe.

Large terrestrial wildlife negatively impacts agricultural livelihoods on all continents except Antarctica. There is growing recognition of the need to reconcile these impacts to achieve socially and ecologically sustainable wildlife conservation agendas. Elk populations in northern California are estimated to have doubled in the past 35 years, marking a conservation success, but also increasing forage loss and damage to infrastructure on private land. Wildlife managers are pursuing the goal of increasing elk numbers on public lands, but elk are preferentially utilizing private pasture and rangeland, driving conflict with beef and dairy producers. We conducted 17 semistructured interviews with private landowners, primarily beef and dairy producers, in northern California to understand their experiences and reactions to elk conflict and state wildlife management. Landowners report that elk density on private rangeland has steadily increased in recent years and poses a threat to their businesses due to loss of forage, damage to fences, and the corresponding liability risk posed by breached fences and errant cattle. The absence of crop and forage loss compensation, difficulty obtaining depredation permits, and low harvest quotas for recreational hunting limit landowner mitigation options and foster resentment toward the state wildlife agency. Most landowners believe that current elk management policies, including restricted hunting opportunities, do not adequately address elk conflict, creating novel challenges for wildlife officials tasked with reconciling elk restoration goals with a variety of stakeholders experiencing economic losses and threats to rural livelihoods. We discuss these issues in the context of common wildlife management challenges, such as building social capital, defining tolerable impacts, and building institutional capacity for alternative solutions within rigid regulatory frameworks. We draw upon environmental economics and common-pool resource theory to suggest that a rethinking of elk management based on local conditions, facilitating damage compensation mechanisms while reducing transaction costs, and increasing participation of local stakeholders in decision making might improve outcomes.

Vegetation demographic models (VDMs) endeavor to predict how global forests will respond to climate change. This requires simulating which trees, if any, are able to recruit under changing environmental conditions. We present a new recruitment scheme for VDMs in which functional-type-specific recruitment rates are sensitive to light, soil moisture and the productivity of reproductive trees.We evaluate the scheme by predicting tree recruitment for four tropical tree functional types under varying meteorology and canopy structure at Barro Colorado Island, Panama. We compare predictions to those of a current VDM, quantitative observations and ecological expectations.We find that the scheme improves the magnitude and rank order of recruitment rates among functional types and captures recruitment limitations in response to variable understory light, soil moisture and precipitation regimes.Our results indicate that adopting this framework will improve VDM capacity to predict functional-type-specific tree recruitment in response to climate change, thereby improving predictions of future forest distribution, composition and function.