One Earth最新文献

Biochar plays a vital role in carbon dioxide removal and achieving carbon neutrality, yet its diverse applications remain underexploited due to techno-economic barriers and limited industry-academia-government cooperation. Enhancing scientific innovation, cross-disciplinary collaboration, and robust policy and regulation support are essential to maximize its positive climate impact.

Carbon dioxide removal (CDR) policy is evolving rapidly but remains fragmented. Upcoming initiatives by the G7 members, which face expectations to be frontrunners in CDR deployment, should follow five principles for robust policies. This will be critical to prepare for distributional conflicts associated with achieving net-zero and net-negative emissions, both domestically and internationally.

Carbon dioxide removal (CDR) is increasingly recognized as essential for achieving the Paris Agreement’s climate goals. Current CDR strategies primarily involve land-based measures, such as afforestation, reforestation, and soil carbon enhancement. These approaches, often labeled as nature-based solutions (NBS) or natural climate solutions (NCS), have sparked debate due to their potential adverse effects on biodiversity and uncertainty around the scale and durability of potential climate benefits. This paper introduces a framework for evaluating trade-offs in land-based CDR activities following the recent United Nations Environment Assembly definition of NBS. This framework emphasizes ecosystem integrity, human rights, and sustainable development, aligning with the objectives of the three Rio Conventions, which provide a guardrail to inform pathways toward feasible and equitable implementation. By applying this framework, we provide a more comprehensive understanding of the environmental and social constraints on CDR, ensuring that climate mitigation efforts do not compromise biodiversity, ecosystem services, or human well-being.

Many modeling studies depend on direct air capture (DAC) in their 1.5°C stabilization scenarios. These studies rely on assumptions that are overly optimistic regarding the cost and scaling-up of DAC systems. This can lead to highly misleading results that can ultimately impact the ability to reach climate stabilization goals.

The growing demand for woody biomass to meet the environmental and climate objectives of the European Green Deal raises concerns about the capacity of forest ecosystems to sustain their diverse services and functions. Deadwood, an often-overlooked source of biomass, exemplifies this dilemma, yet the evidence needed to enhance its management is sparse. Here, we put the role of deadwood into perspective through a literature review and comparison of estimates in managed and unmanaged forests. We demonstrate that deadwood intersects many overlapping and sometimes conflicting policies, playing a multifaceted role in the bioeconomy, biodiversity conservation, soil health, fire mitigation, bioenergy, and carbon storage. Given the increasing pressure on deadwood and the ecosystem services it provides, we argue that coherent and mutually supportive policies are needed to develop multifunctional pathways that reconcile deadwood management with biodiversity, bioenergy, and climate objectives. Therefore, we suggest that harmonized data and monitoring are essential, along with transdisciplinary collaboration, to identify trade-offs between biomass uses and values and ensure the maintenance of functional forest ecosystems.

Low knowledge sharing across disciplines studying geo-evolutionary processes determining species adaptations hinders the mitigation of biodiversity loss driven by human-induced climate warming. Further, the impacts of microbes and light regimes on species adaptations to accelerated climate warming are largely ignored. On a geologic timescale, range shifts to higher latitudes necessitate adaptation to new light environments, including extreme polar seasons, i.e., "polar night." Chemical crosstalk among coevolving microbes and plants modulates ecologically relevant traits, and photosensitive and other microbes may aid plant adaptation. We hypothesize that hybridization in new "circumpolar hybrid zones” and plant-microbial cooperation in those zones and elsewhere will be significant in maintaining genetic admixture and species diversity on a geological timescale. We propose the concept of circumpolar hybrid zones and an integrated framework, inclusive of microbes, to unite disparate research disciplines, advance understanding of evolution, and improve strategies for climate adaptation and mitigation.

Climate change has intensified extreme temperature events, posing significant challenges to public health and equity. While the impact of extreme temperatures on mortality is known, racial disparities in this context are less explored. Most studies on the United States focus on specific regions or do not address the effects of cold. We provide a comprehensive assessment across the country using a new database of linked administrative and census data with precise meteorological information. Analyzing death records from over 3,000 counties (1993–2005), we find that both cold and hot days increase mortality rates, with hot days disproportionately impacting racial minorities. Our analysis suggests that recent temperature increases could exacerbate racial disparities in temperature-related deaths, highlighting the need to investigate how climate change affects different population subgroups and exacerbates social inequities.

Nine years after the Paris Agreement was adopted, it is clear that negative-emission technologies are required to keep 1.5°C, or even 2°C, of global warming in reach. Yet carbon dioxide removal (CDR) strategies remain rife with political, technical, economic, environmental, and geographic challenges. This Voices surveys the pitfalls of incorporating carbon-negative technologies into climate mitigation plans and asks: how can we navigate around the challenges to make CDR a reliable component of climate mitigation?

Expectations for agricultural landscapes in subtropical and tropical regions are high, aiming for conservation and development amid climate change, unfair trade, poverty, and environmental degradation. Landscape approaches (LAs) are gaining momentum as means to reconcile expectations, although they face multiple challenges, including unclear distinctions among LAs and stakeholder involvement. We studied 380 LAs from three continents via questionnaires with landscape managers (2012–2015 and 2021) and identified three LA types through cluster analysis: an “integrated” type with longer-term, multisectoral goals involving various stakeholders early in the design and two shorter-term types focused on sectoral priorities of preservation or production. Better-performing LAs are associated with longevity, inclusivity, and diversified investments across goals, notably those enabling social justice. International stakeholder analysis shows broad support for LAs but identifies gaps between support and LAs’ needs. The growing interest in LAs is promising. Yet, underpinning effective and lasting LAs that reconcile multiple expectations requires better support.