The demand for intensive agriculture to boost food and crop production has increased. High nitrogen (N) fertilizer use is crucial for increasing agricultural productivity but often leads to significant nitrate losses, posing risks to surface and groundwater quality. This study examines the role of biochar as a soil amendment to enhance nutrient retention and mitigate nitrate leaching. By improving nitrogen efficiency, biochar offers a sustainable strategy to reduce the environmental impacts of intensive agriculture while maintaining soil fertility. An incubation study investigated four biochar feedstocks: spruce bark biochar at 550 °C (SB550), hardwood biochar (75% sugar maple) at 500 °C (HW500), sawdust (fir/spruce) biochar at 427 °C (FS427), and softwood biochar at 500 °C (SW500), to identify the most effective nitrate adsorbent. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) were employed to analyze biochar morphology and surface functional groups. Adsorption isotherms were modeled using the Langmuir and Freundlich equations. The results indicated that surface functional groups, such as aromatic C=C stretching and bending, aromatic C–H bending, and phenolic O–H bending, play crucial roles in enhancing electrostatic attraction and, consequently, the nitrate adsorption capacity of biochar. The equilibrium adsorption data from this study fit well with both the Langmuir and Freundlich isotherm models. Among the four biochar types tested, SB550 exhibited the highest nitrate adsorption capacity, with a maximum of 184 mg/g. The adsorption data showed excellent conformity to the Langmuir and Freundlich models, with correlation coefficients (R²) exceeding 0.987 for all biochar types. These findings highlight the high accuracy of these models in predicting nitrate adsorption capacities.

, weak sustainability, three-pillar approach, strong sustainability, transdisciplinary approach

Biochar has broad applications in agriculture, where its incorporation into soils is recognized as an effective strategy for improving soil quality, enhancing remediation, sequestering carbon, and mitigating climate change. Although the application of nitrogen fertilizers can enhance nitrogen leaching, integrating biochar may improve nutrient retention and reduce associated losses. However, the effects of biochar on nitrogen and carbon leaching in specific soil types remain unclear. This study investigated the impact of spruce bark biochar (SB550) on the leaching of total nitrogen (TN), nitrate (NO₃⁻), ammonium (NH₄⁺), and dissolved organic carbon (DOC) in agricultural soils of eastern Newfoundland. A greenhouse experiment was conducted with Festulolium forage grown in a soil–biochar mixture at five biochar rates (0, 2, 5, 8, and 10% v/v), with and without nitrogen fertilizer (0 and 60 kg N ha⁻¹). The results showed that SB550 biochar significantly reduced nutrient and carbon losses (p < 0.001). At the 10% biochar rate, leaching of NO₃⁻, NH₄⁺, TN, and DOC decreased by 48.6%, 80.4%, 60.0%, and 74.3%, respectively, compared with the control. These findings confirm that the addition of biochar is an effective amendment for minimizing nitrogen and DOC leaching, offering a promising strategy for sustainable nutrient management and environmental protection in this soil type.

Biochar has been widely used in agriculture to improve soil quality, support soil remediation, enhance carbon sequestration, and mitigate climate change. Podzolic soils, such as those in Newfoundland, are typically acidic, low in organic matter, and poor in nutrients, which can limit their agricultural productivity. Applying biochar alongside nitrogen fertilization presents a promising strategy to enhance soil fertility, nutrient uptake, and forage productivity. This study evaluated the effects of spruce bark biochar (SB550) and nitrogen fertilization on soil properties, nutrient uptake, and Festulolium forage growth under greenhouse conditions in podzolic soils of Newfoundland, Canada. Five biochar rates (0%, 2%, 5%, 8%, and 10% by soil volume) were combined with two nitrogen levels (0 and 60 kg N ha⁻¹). Soil analyses included pH, soil organic matter (SOM), cation exchange capacity (CEC), and nutrient availability (Ca, Mg, K, P, S, Zn, Mn, and B). In contrast, forage nutrient uptake, biomass production, and quality were assessed. Results showed that biochar significantly increased soil pH, SOM, CEC, and nutrient availability for key elements such as Ca, Mg, and K, while reducing potentially harmful elements such as Na and Mn. The Festulolium nutrient uptake and biomass improved, with dry matter and root biomass increasing by up to 32%. The combined application of biochar and nitrogen further amplified these benefits. This study highlights the potential of biochar as a sustainable soil amendment for improving soil properties and forage productivity in podzolic soils. The findings suggest that biochar, particularly with nitrogen, can significantly enhance soil fertility and agricultural productivity, making it a viable strategy for sustainable forage production in Newfoundland.

Arctic–boreal wetlands and lakes are among the most significant and most uncertain natural sources of atmospheric methane. Rapid Arctic amplification, permafrost thaw, hydrological change, and increasing ecosystem productivity are expected to intensify methane emissions from high-latitude landscapes. Yet, significant uncertainties persist in quantifying their magnitude, seasonality, and spatial distribution. This review synthesizes the current state of the art in monitoring methane emissions from Arctic–boreal wetlands and lakes through complementary bottom-up and top-down approaches. We examine Earth observation (EO) capabilities, including optical, thermal infrared (TIR), and synthetic aperture radar (SAR) missions, as well as new emerging satellite platforms. We also assess in situ measurement networks, wetland and lake inventories, empirical and process-based models, and atmospheric inversion frameworks. Key gaps remain in representing small waterbodies, shoreline heterogeneity, winter emissions, inventory harmonization, and integration between atmospheric retrievals and surface-based flux models. Moreover, advances in multi-sensor data fusion, explainable artificial intelligence (XAI), physics-informed inversion methods, and geospatial foundation models offer strong potential to reduce these uncertainties. A coordinated integration of satellite observations, field measurements, and transparent modeling frameworks is essential to improve Arctic–boreal methane budgets and strengthen projections of climate feedback in a rapidly warming region.

This review assessed the sustainability of rural livelihood assets from implementation of payments for forest ecosystem services programs (PFESPs) in developing countries. The study aimed to test an overall hypothesis that PFESPs could contribute to sustainable livelihoods for program participants (PPs) better than for non-participants (NPs) by constructing a sustainable livelihood index (SLI). A systematic assessment design was used to collect and analyze data from 34 PFESPs in developing countries across 41 dependent studies. The SLIs for both groups were explored using the UK Department for International Development (DFID) methodology based on the five livelihood capitals (natural capital - NC, financial capital–FC, physical capital–PC, human capital–HC and social capital–SC). The main findings were emphasized by applying the equal weighting approach, the Mann-Whitney U test and Fisher p-value combination. Then, alternative weighting schemes (from ±5% to ±15%) were applied to conduct sensitivity analysis (SA) of the main findings. Both the equal and alternative weighting approaches supported our overall hypothesis that PFESPs offered more benefits for PPs in PFESPs than for NPs and their five livelihood indices were generally unbalanced showing skewed pentagons. The main findings revealed that PPs’ SLI’s value was 0.74 (potentially sustainable degree) compared to NPs’ SLI’s value of 0.41 (potentially unsustainable). Although the difference in overall livelihood value between the two groups was determined at the statistical significance of p < 0.05, the size strength was small (r < 0.3). While the alternative findings suggested that the SLI outcomes of both groups were generally responsive to any single input changes around the base case (equal weighting), the low SI (≤10% or Score 1) was found as the most common for both groups, but higher for PPs (82%), compared to NPs (56%). However higher SI rates were more common for NPs than for PPs. The policy implications for SRL should be based not only on SA results, the relationships between livelihood inputs weighting schemes and expected sustainable livelihood outputs, but also on the specific place-based context and stakeholders’ inputs.