Frontiers in Ecology and the Environment最新文献

Changing climatic conditions are increasing overstory tree mortality in forests globally. This restructuring of the distribution of biomass is making already flammable forests more combustible, posing a major challenge for managing the transition to a lower biomass state. In western US dry conifer forests, tree density resulting from over a century of fire-exclusion practices has increased the risk of high-severity wildfire and susceptibility to climate-driven mortality. Reducing dead fuel loads will require new approaches to mitigate risk to the remaining live trees by preparing forests to withstand future wildfire. Here, we used data from the Teakettle Experimental Forest in California to evaluate different prescribed fire burn frequencies and their impact on accumulated dead fuels after a 4-year drought. Increasing burn frequency could reduce surface fuel build-up but comes with additional challenges that will require creativity and experimentation to overcome.

Local-scale environmental justice studies of freshwaters have found that marginalized populations are more likely than others to be burdened with poor-quality waters. However, studies have yet to examine whether monitoring data are sufficient to determine the generality of such results at the national scale. We analyzed racial and ethnic community composition surrounding lakes and the presence of one-time and long-term (≥15 years) water-quality data across the conterminous US. Relative to lakes in White and non-Hispanic communities, lakes in communities of color and Hispanic communities were three times less likely to be monitored at least once. Moreover, as compared to lakes in White communities, lakes in communities of color were seven times less likely to have long-term monitoring data; similarly, as compared to lakes in non-Hispanic communities, lakes in Hispanic communities were nineteen times less likely to have long-term monitoring data. Given this evidence, assessing the current water quality of and temporal changes in lakes in communities of color and Hispanic communities is extremely difficult. To achieve equitable management outcomes for people of all racial and ethnic backgrounds, freshwater monitoring programs must expand their sampling and revise their designs.

Transformative change is needed to align common small-scale ecological restoration approaches with expectations to restore millions of hectares of degraded lands globally. Currently, most restoration projects target small areas using costly manual methods that cannot be scaled up to meet global commitments. We propose that a judicious integration of agricultural practices into ecological restoration offers an opportunity to address this issue. This transformative process relies on three sequential and interconnected steps: (1) ensure that sufficient land is truly available for restoration; (2) compensate for the loss of agricultural production, income, or land value to encourage landholders to opt for restoration; and (3) develop scalable, affordable, and effective methods for restoring native ecosystems across the pledged hundreds of millions of hectares to deliver benefits to both nature and people. Large-scale terrestrial restoration will require incorporating agronomic practices into the restoration toolbox to go beyond vague, ambitious promises and wishful thinking.

In navigating the biodiversity crisis, a major uncertainty is the conservation status of inconspicuous, yet megadiverse and functionally crucial, soil organisms. Massive datasets on soil biota are accumulating through molecular sampling approaches, but to date these datasets have provided only limited input into conservation planning and management. We investigated how environmental DNA (eDNA) data of soil macrofungi contribute to regional Red List assessments, which are currently based on fruiting bodies (hereafter, fruit-bodies). In our test region of Estonia (northern Europe), which contained ~15,000 fruit-body records for 1583 assessed species, an average soil sample increased the range estimates of Threatened and Near Threatened fungal species by 0.18%. Five hundred soil samples almost doubled their known localities and added 19% previously unrecorded species. However, even after accumulating >1000 soil samples, about half of the Threatened and Near Threatened species known by fruit-bodies remained undetected through eDNA techniques. Effective conservation assessment of soil fungi thus requires both fruit-body and eDNA data; therefore, special efforts are needed to make these data available to conservationists.

Supplementary feeding of garden birds and gamebirds is a common practice worldwide. Bird feed is rich in phosphorus (P), which plays a key role in animal health and ecosystem function. However, much of the P in bird feed originates from mined rock deposits, which is then transported thousands of kilometers to feeder stations, where it represents an external source of nutrients for recipient ecosystems. Here, we demonstrate that diffusion of P by birds and other animals from feeder stations to ecosystems can represent a nontrivial contribution to local biogeochemical cycles. Using the UK as a case study, we show that supplementary bird feeding supplies 2.4 (range: 1.9–3.0) gigagrams of P per year across the UK, a flux similar in magnitude to atmospheric deposition. Phosphorus provided to garden birds alone is equal to that supplied through the application of garden fertilizers. In natural and semi-natural ecosystems, additional feeder-derived P inputs may exacerbate eutrophication at the local scale and adversely impact biodiversity.