Princeton Public Schools

Riparian buffers - vegetation strips retained or established along waterways - are mandated in many countries for water and soil protection, yet their role in biodiversity conservation remains unclear. Our global meta-analysis compares forested riparian buffers with converted riparian zones in human-modified landscapes across forest biomes. We find that forested riparian buffers support higher animal biodiversity than converted riparian zones at both local and landscape scales, particularly in agricultural areas. This pattern is consistent across most freshwater and riparian taxa, in both tropical and temperate regions. Forested riparian buffers also harbor, on average, 32% more reference species (i.e., species found in continuous riparian forests) than do converted riparian zones. Optimum forested buffer width estimates for species conservation are roughly an order of magnitude wider for birds and mammals (200-380 m on each river side), than for amphibians (20-50 m) and invertebrates (6-50 m). Our findings support forested riparian buffers as an important global strategy for conserving biodiversity in forest biomes.

Abstract The Amazonian manatee ( Trichechus inunguis) , a vulnerable species native to the Amazon River Basin, is threatened by habitat loss, illegal hunting, and pollution. Rehabilitation centers rescue, rear, and release manatees negatively impacted by human activities. Factors characterizing the survival of rescued manatees at these rehabilitation centers remain unclear. We analyzed data from 54 rescued manatees at a rehabilitation center in the Peruvian Amazon, assessing factors hypothesized to be predictors of the probability of survival during the rehabilitation process. We found that initial weight at intake and the rate of weight gain while at the center were significantly associated with a higher probability of survival. Intestinal obstruction, often linked to inappropriate diets prior to rescue, was the leading cause of death while in rehabilitation (13 of 54 individuals; 24%). Early intervention to transport orphaned calves to rescue centers and equipping local authorities with resources for short‐term care until transportation is possible could improve rescue outcomes.

ABSTRACT An advanced exploration of polycentric climate governance is essential to achieve global mitigation goals. This study draws on social network analysis, surveys, and 86 qualitative interviews with policy actors in the Indian power sector. It investigates the role of the state in enabling or constraining actor participation versus the extent to which actors self‐organise into belief‐based coalitions to influence energy transition policy. By engaging with political economy frameworks, the paper furthers the literature on polycentric governance, unravelling actor interests and relationships. The results show that while India's power sector includes a diverse set of policy actors, they do not form coalitions based on shared policy beliefs. Rather, the central government plays a dominant role, influencing the extent to which different actors participate in the polycentric policy network. However, this central state apparatus itself is non‐monolithic with uneven power dynamics across its various agencies and ministries. The Indian government pushed ambitious clean energy policies to encourage self‐organisation between subnational government and private players. Civil society operates in a limited policy space, invited to participate to carry out the national energy transition policy agenda. The selective empowerment of actors by the central state has reshaped governance towards increased renewable energy adoption. However, the imbalanced participation of different actors may limit the potential for rapid and deep decarbonisation. Future work should study how an increasingly dominant private sector empowered by the state and a civil society that is nudged to the periphery impacts climate coalition building within polycentric networks.

<strong class="journal-contentHeaderColor">Abstract.</strong> India experiences some of the highest PM_2.5 concentrations globally. Understanding the spatiotemporal variations of PM_2.5 and its source attribution requires robust air quality modeling supported by up-to-date emission inventories. Here we present the first WRF-Chem model evaluation and source attribution analysis for India for 2022, supported by updates in sectoral emission inventories and model schemes. We incorporate an updated residential emission inventory reflecting recent transitions to cleaner fuels in Indian households and develop a plant-level inventory for Indian coal-fired power plants. Further major improvements include model updates to the secondary organic aerosol scheme and an improved representation of near-surface pollutant mixing. Collectively our improvements result in a simulation with annual PM_2.5 bias of only 0.2&plusmn;16.9 &mu;g/m³ (0 &plusmn; 31 %) across 288 surface monitoring sites in South Asia. We find that, compared to earlier studies, in 2022 India's residential sector remained the dominant source of PM_2.5 in the Indo-Gangetic Plain, but nationally ranked second in population-weighted (PW) mean PM_2.5 concentrations contributing 15 % (7.3 &mu;g/m³). Instead, industrial emissions emerged as the largest domestic contributor to national PW mean PM_2.5 (18 %, 8.6 &mu;g/m³), with urban hotspots including Delhi and Mumbai. The power sector contributions ranked third nationally (13 %, 6.1 &mu;g/m³) and was particularly influential in central India. Transboundary transport contributed more than any individual domestic source nationally (27 %, 12.8 &mu;g/m³). These findings highlight the benefits of India's partial residential sector transition toward cleaner fuels, while underscoring the growing consequence of industrial and power sector emissions that have limited pollution controls.

The impact of increasing anthropogenic hydrogen (H2) emissions on Earth’s radiative balance depends on the soil microbial H2 sink—the largest and most uncertain term in the global H2 budget. Soil moisture is a primary but poorly quantified control regulating the soil sink. Here, we assess the sensitivity of microbial H2 oxidation to soil moisture in laboratory experiments with temperate and arid soils spanning distinct textures. We report H2 oxidizer activity down to –70 to –100 MPa water potentials across soils, which are among the driest conditions reported for microbial activity and are much drier than assumed in global simulations of H2. Using genome-resolved meta-omics, we link H2 oxidation dynamics in temperate soils to specific desiccation-adapted microbial taxa that contribute differentially to H2 uptake along the moisture gradient. Through global simulations, we show that our observationally constrained drier moisture threshold increases the contribution of arid and semi-arid regions for soil H2 uptake by 4-7 percentage points (pp), while decreasing the contribution of temperate and continental regions (−7 pp). Our results highlight the importance of H2 uptake under extreme hydrological conditions, particularly the roles of desertification, dryland expansion, and H2-oxidizer ecophysiology in modulating long-term changes in H2 uptake.

Abstract In many countries, declining demand in energy-intensive industries (EIIs) such as cement, steel, and aluminum is leading to industrial overcapacity. Although industrial overcapacity is traditionally envisioned as problematic and resource-wasteful, it could unlock EIIs’ flexibility in electricity use. Here, using China’s aluminum smelting industry as a case, we evaluate the system-level cost-benefit of retaining EII overcapacity for flexible electricity use in decarbonized energy systems. We find that overcapacity can enable aluminum smelters to adopt a seasonal operation paradigm, ceasing production during winter load peaks exacerbated by heating electrification and renewable seasonality. In the 2050-net-zero scenario, the seasonal operation paradigm can reduce China’s electricity system investment and operational costs by 15-72 billion CNY/year (or 8-34% of the aluminum smelting industry’s product value), sufficient to offset the costs of maintaining overcapacity and product storage. It also reduces workforce fluctuations across the aluminum smelting and thermal power generation sectors by up to 62%, potentially mitigating socio-economic disruptions from industrial restructuring and energy transition.