Arctic marine mammals are increasingly affected by the combined pressures of climate change and expanding human activity. Although individual stressors such as sea ice loss, underwater noise, and chemical pollution are well studied, their interactive effects remain poorly understood, complicating ecosystem-based conservation. We systematically screened 1084 peer-reviewed studies from 1984 to 2025 (Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)) to identify dominant stressor pathways and species-specific vulnerabilities. Six major stressors emerged: sea ice decline, noise pollution, chemical contaminants, industrial expansion, shifts in prey availability, and disease or biotoxins. We synthesize these findings into a stressor-interaction framework classifying combined effects as additive, synergistic, or antagonistic; Antagonistic interactions occur when the combined effect of two stressors is weaker than expected based on their individual impacts. Across taxa, overlapping pressures reduce movement, foraging success, and habitat use, particularly for narwhals, belugas, bowhead whales, and polar bears, whose ice dependence and slow reproduction heighten risk. High-risk combinations, such as contaminant remobilization during nutritional stress or the dual effects of sea-ice loss and industrial noise, highlight the need for dynamic protected areas, strengthened regulatory measures, and co-management approaches incorporating Indigenous knowledge. A clearer understanding of synergistic and cumulative effects is essential as environmental change accelerates.

Global aridity is increasing due to anthropogenic warming, which raises atmospheric evaporative demand faster than precipitation. As a result, more land and populations are exposed to arid conditions, a trend projected to intensify in the coming decades. Aridity is a long-term climatological condition that affects large regions worldwide. Unlike short-term phenomena such as droughts, aridity leads to gradual but increasingly detrimental impacts on biophysical and socio-economic systems. Over time it can transform landscapes into desert-like environments, hindering the development of life and compromising the well-being of societies. The impacts of aridity are complex and diverse, and it is especially challenging to assess its effects on socioeconomic systems. Yet no global review has systematically examined the impacts of aridity, the factors driving societal vulnerability, and the adaptation measures being implemented. This paper provides the first comprehensive synthesis of these dimensions, thereby filling a critical gap in the literature. Our review shows that while references to biophysical impacts are increasing, explicit studies on socio-economic consequences—such as those on food production, poverty, health, and migration—remain scarce. These are often inferred indirectly from related concepts like drought or desertification. By systematically integrating this dispersed evidence, our article highlights both natural and socio-economic impacts, identifies key knowledge gaps, and outlines priority areas for future research. Such knowledge is essential for improving mitigation and adaptation strategies that strengthen resilience in increasingly arid regions.

Soil heavy metal(loid) pollution remains one of the most critical environmental challenges worldwide, and increasing attention has been paid to remediation strategies. Phosphate-solubilizing microorganisms (PSMs) have been identified as promising bioremediation microorganisms being due to their multifunctional roles in nutrient cycling and heavy metal(loid) stabilization or mobility. This review provided the remediation mechanisms of heavy metal(loid) contaminated soils by PSMs, including surface adsorption, chelation with siderophores, organic acids and exopolysaccharides. During the remediation process, PSMs could also enhance the soil available phosphorus which could further immobilized heavy metal(loid)s. The PSMs could also combine with hyperaccumulators and soil amendments to increase the remediation efficiency through altering the bioavailability of heavy metal(loid)s. The remediation efficiency of PSMs could be influenced by soil characteristics, environmental conditions and heavy metal(loid) properties, which relating with the PSMs activity. The PSMs application may also result in soil acidification, disrupt the native microbial communities, and increase the mobilization of heavy metal(loid)s, which could not be ignored. This work will provide guideline for the safe and effective remediation of metal(loid)-contaminated soils using PSMs. Future research should aim to optimize PSM application on enhancing the remediation efficiency of contaminated soils and decreasing the ecological risks.

Co-limitation is defined as the coincident limitation of biological activity by multiple resources. According to theories of resource optimization, co-limitation should be common as organisms adjust to changes in the availability of resources in the environment. We review the multi-faceted nature of the co-limitation concept and provide a synthesis of recent experimental studies of co-limitation in northern hardwood forests to illustrate the complexities of nitrogen (N) and phosphorus (P) co-limitation and possible responses to environmental stressors such as acid rain, N deposition, elevated CO2, land-use, and climate change. In a factorial nutrient addition experiment, cycling of one nutrient changed in response to addition of the other through synergistic interactions and feedbacks between N and P, including microbial recycling, soil enzyme activity, and foliar nutrient resorption; these responses were suggestive of some degree of N–P co-limitation in these forests. After 8 years of treatment, aboveground growth increased in response to either N or P added individually and even more in response to N + P addition, indicating N–P co-limitation. Surprisingly, fine root growth increased in response to nutrient addition, with significantly greater root growth in N + P plots in five successional stands and in N plots in three mature stands. In contrast, fine litterfall did not respond significantly to nutrient addition. Collectively, these results demonstrate the complexity of the interactions between macronutrients in regulating production processes in forest ecosystems.

While they are important, local or catchment-level conservation efforts are by themselves unlikely to bend the curve of dramatic global-scale biodiversity loss in rivers, lakes, and freshwater wetlands. Other interventions will also be required, especially those that address the underlying socio-economic drivers of freshwater ecosystem degradation. Such drivers often manifest through decisions made at national or international scales by policymakers and business leaders in sectors including water resource management, agriculture and food production, energy generation, and inland fisheries. Few analyses have traced the impacts of such decisions on freshwater ecosystems and biodiversity, and the evidence base provides scant insight into effective approaches for addressing these underlying drivers. We begin to address this strategic knowledge gap by describing key policy and business sectors that the conservation and science communities should engage to address the systemic drivers of global freshwater biodiversity loss. Drawing on diverse experiences of international policy and business discourses and applied freshwater sciences, we provide an overview of international sector-specific risks and opportunities for freshwater conservation and propose potential priorities for engagement. We reflect on actions the freshwater sciences community can take to respond to these risks and opportunities, and we suggest priorities to shape a more systemic, driver-focused approach to freshwater conservation research that can support the integration of freshwater biodiversity considerations into policy and business decisions.

Metal mining activities have been major contributors of potentially toxic elements (PTEs) in the environment, leading to substantial soil pollution. One such example is lead–zinc mining around the world. Elevated concentrations of PTEs are commonly detected in nearby areas of both active and abandoned mines. This is primarily attributed to the release and dispersal of untreated waste materials from these mines into the surrounding environment. Mining-related soil pollution with PTEs can pose many different kinds of risks in a variety of contexts such as eco-toxicity, phytotoxicity, human health risk, as well as soil and water pollution. This review summarizes available data in the literature (2000–2023) on PTEs polluted soils originating from lead–zinc mining areas across the world. In this study, an attempt has been taken to evaluate the pollution level of PTEs in soils using collected data. The study shows the most polluted world regions are reported in Asia, followed by Europe and Africa, and only a few studies are reported in north, central and south America. The elements commonly analyzed in conjunction with Pb and Zn were Cd and Cu, whereas those responsible for increased pollution were Cd > As > Cu > Hg–Mn–Tl. Assessment of the pollution and health hazards has shifted to include a variety of quality indexes, including multivariate statistical analyses and microbial diversity.

Wet atmospheric deposition, primarily through rainfall, plays a crucial role in removing atmospheric pollutants, particularly water-soluble particles and dissolved gases, thereby contributing to atmospheric cleansing. This review article examines the ionic composition of rainwater in Latin America, based on scientific studies retrieved from the Web of Science and Scopus databases. The findings reveal that anthropogenic sources of ionic compounds in rainwater include fossil fuel combustion, fertilizer application, vehicular emissions, and industrial activities, which primarily contribute to acidifying compounds. In contrast, neutralizing compounds (e.g., Ca2+ and Mg2+) originate from both human activities and natural sources, such as marine aerosols and dust resuspension. Elevated concentrations of acidifying compounds have been documented in urban and industrial areas, whereas rural regions predominantly exhibit neutralizing ions. In certain countries, such as Brazil and Costa Rica, reductions in the sulfur content of fuels have led to trends of rainwater neutralization. The ratios of ionic compounds (e.g., SO42−/NO3− and NH4+/NO3−) and rainwater pH were analyzed to identify emission sources and regional patterns, revealing geographical, seasonal, and local influences on emissions. However, documentation on the impacts of rainwater acidification in Latin America remains limited, with most studies focusing on Brazil. Mexico, Argentina, and Brazil have been identified as the most productive countries in this research area. Nevertheless, studies on the ionic composition of rainwater in Latin America remain scarce and have declined over the past 5 years. This decline is concerning given the region’s rich biodiversity, which may be adversely affected by rainwater acidification.

The integrated application of biochar, hyperaccumulators, and specific microorganisms offers an effective and environmentally sustainable bioremediation strategy for heavy metal-contaminated soils. However, most current research predominantly focuses on preliminary investigations and pairwise interactions among these components, critical gaps still persist in understanding the complex soil rhizosphere interface reactions and the functional role of extracellular polymeric substances (EPS) in this ternary system. This paper first provides a relatively comprehensive review to the individual remediation effects along with involved mechanisms of biochar (enhanced adsorption/stabilization), hyperaccumulators (phytoextraction), and microbes (biotransformation), and then advances the discussion by elucidating the synergistic interactions within the biochar–hyperaccumulator–microbe ternary framework. Key aspects include the biochemical pathways and regulatory mechanisms governing microbial EPS production, the role of EPS in remediating soil heavy metals, and the dynamic root–microbe interactions at the rhizosphere interface under heavy metal stress. By integrating molecular-scale insights with field-scale applicability, this study provides technical references and theoretical foundations for the future combined application of biochar with microorganisms, hyperaccumulators, and other environmental elements to achieve more efficient and sustainable remediation of metal-contaminated soils.

Arsenic (As) pollution of agricultural soil is of major concern due to its negative impacts on the human population worldwide, with exposure mainly occurring through food chain contamination. To alleviate As toxicity in humans, researchers have focused on restricting its entry into the food chain. Fungi are promising candidates for soil As detoxification as they possess different mechanisms to reduce As bioavailability in the soil through biosorption, bioaccumulation, biotransformation, and biomethylation/biovolatilization. The As-remediating potential of fungal strains can be improved by various biotechnological approaches, viz., protoplast-mediated transformation, restriction enzyme-mediated integration, CRISPR Cas9, etc. These techniques coupled with appropriate selection criteria and their validation through extensive in vitro and in situ (field) trials would result in genetically improved novel fungal strains that can be applied to As-contaminated agricultural fields for alleviating As toxicity in agro-ecosystems.