Environmental and Earth Sciences

Abstract: Corporate carbon offsetting schemes heavily rely on tree planting for carbon sequestration, and in Scotland the government presents tree planting as a key carbon sink in the face of climate change. However, carbon offsetting schemes rarely consider associated fluxes in soil organic carbon (SOC) driven by afforestation. Soils in woodlands store approximately 75% of the total ecosystem carbon, yet planting trees on existing carbon-rich soils or grassland may result in changes in soil carbon that take decades for tree biomass to recover. This study provides a methodological framework using the chronosequence approach (space-for-time substitution) to measure whole-ecosystem carbon storage for existing commercial carbon sequestration schemes. A proof-of-concept pilot study was carried out at the University of Edinburgh’s Rullion Green site, gathering 35 soil samples across unplanted baselines, a recent 2025 planting scheme, and a mature mixed woodland. The findings of this proof-of-concept study show that soil carbon in the newly planted area (5.06% SOC) was lower than in the mature woodland (7.64% SOC) and remained statistically similar to the unplanted baseline (7.11-8.65% SOC depending on slope). The carbon in the recently planted trees (4.10 t C/ha) did not offset the carbon losses from soil, with a drop in ecosystem carbon of 156.41 t C/ha compared to the baseline, and 418.23 t C/ha compared to the mature woodland. The methodology and trial study suggest that initial tree planting may not guarantee an immediate net increase in ecosystem carbon until trees become mature. The methodology therefore provides a tool to help mitigate greenwashing in the offsetting industry. The methodology will now be applied in further research to other sites across northern England to determine what the impact of tree planting for carbon sequestration is on soil in the UK.

Abstract: Large-scale efforts to catalog the fossil record and digitize museum collections have driven the recognition of two distinct forms of fossil records: the physical record, consisting of specimens, and the abstracted record, consisting of data derived from those specimens. This framework provides a conceptual basis for distinguishing between specimen-based and data-driven resources for teaching and learning paleontology in formal educational settings. In this position paper, we show that state-of-the-art paleontological research increasingly conceptualizes the so-called abstracted fossil record not merely as digital data or archives (e.g., databases, digital models, and imagery), but primarily as complex representations of the spatiotemporally resolved and high-dimensional geohistorical data. Building on this perspective, we highlight a major gap between modern paleontological research and teaching practices in higher education, where paleontology courses often rely on the specimen-data dichotomy and ignore that abstracted representations of the fossil record, such as network models, encode assumptions about its spatiotemporal structure and dynamics that shape the patterns inferred from fossil data. Because a physical fossil record can give rise to multiple abstracted representations, each capturing different aspects of the underlying data, we introduce the concept of multiple fossil records within a complex network framework. We argue that leveraging network-based tools can bridge paleontological research and teaching practices while fostering systems thinking in the paleontology classroom, consistent with the UNESCO Education 2030 Framework for Action.

Abstract: The disciplinary memory of a scientific community, the collective recognition of the researchers who have most contributed to a field, is a sociologically relevant yet underexplored dimension of Earth sciences. This study presents consensus rankings of geoscientists that developed scientific research about Geology of Portugal. A nomination survey, organized into seven chrono-thematic domains (Geotectonic Framework of the Iberian Peninsula, Precambrian, Lower Paleozoic, Upper Paleozoic, Mesozoic, Cenozoic, and Meso-Cenozoic of the Portuguese Atlantic archipelagos of the Azores and Madeira), was distributed in 2026 to a purposive sample of 230 geoscientists affiliated with Portuguese public universities. Of the 129 responses received, 45 complete responses were included in the ranking analysis. For each domain, complete descriptive statistics are presented, together with rankings of geoscientists with three or more nominations and the cut-off criteria for the biographical corpus. In total, 45 respondents produced 817 nominations, with an average of 6.5 names per list. The results reveal cross-domain consensus, with figures such as António Ribeiro, Paul Choffat, José Madeira, and João Pais emerging as canonical references. At the same time, the asymmetric distribution of nominations, with long tails of geoscientists mentioned only once, indicates that the community's knowledge of past contributions is diverse and partly idiosyncratic. To the best of the authors' knowledge, these rankings constitute the first evidence-based systematization of the disciplinary memory of Portuguese geosciences and provide the empirical basis for the project Geology of Portugal through Faces.

Abstract: Between 1922 and 1926, the Geological Mission of Angola, set up by the High Commissioner Norton de Matos and based in the city of Huambo, surveyed over 30,000 km across the former Portuguese colony, while assembling large collections of fossils and rocks. Led by António Sousa Torres, an experienced naturalist at the Mineralogical Museum of the Faculty of Sciences in Lisbon, the expedition was mentored by the Swiss geologist Ernest Fleury, a renowned teacher on the engineering courses in Lisbon. For those purposes he named three of his former students to join the expedition, for each of them destinated to lead a field brigade. The knowledge generated was disseminated through international conferences and scientific publications produced in collaboration with distinguished foreign specialists. Nevertheless, the Mission’s most significant achievement was the Geological Map of Angola (1:2,000,000) published in 1933. This accomplishment not only fulfilled a political objective but also secured Portugal’s full participation in the International Geological Map of Africa, prepared in accordance with the guidelines adopted at the International Geological Congresses in Madrid (1926) and Pretoria (1929). It also established the basis of the modern geological chartography of Angola, followed by an actualised version in 1954.

Abstract: Feeding the growing global population without permanently overshooting local-to-planetary boundaries demands a transition from conventional resource extraction to holistic models. Current digital twin applications in (sea)food systems primarily focus on predictive monitoring but fail to holistically integrate socio-economic-ecological systems (SEES) and their emergent properties (e.g., sustainability, stability, dynamism, and circularity). However, it remains unknown whether a unified cybernetic architecture can simultaneously satisfy SEES-level properties by bridging asynchronous global supply-demand chains through embedded spatiotemporal feedback loops. This conceptual review argues that a cybernetic twin—defined as the continuous, bidirectional fusion of a SEES and its digital counterpart via recursively coupled algorithms—can bridge this gap by operating across seven interacting phases of the global food continuum at multiple spatiotemporal resolutions. By integrating ecosystem dynamics with real-time simulations, the twin would interact with decision-making processes by rendering transparent and dynamic interactions among SEES-level pathways across aquatic-terrestrial food systems. We propose how a cybernetic twin can be leveraged to achieve sustainable (sea)food quantity and quality in SEES.

Abstract: With the rapid growth of remote sensing data and multimodal information, foundation models for Earth observation and vision–language geospatial reasoning models have become key drivers of intelligent remote sensing analysis. However, the specific roles and applications of reasoning models in remote sensing remain insufficiently explored. This survey defines RS-Reasoning operationally as task-dependent, multi-step inference whose conclusions are supported by traceable visual, temporal, spatial, or tool-derived evidence and are evaluated beyond final-answer accuracy. We organize the literature into three non-exclusive paradigms according to the dominant mechanism by which reasoning is acquired and executed: supervised reasoning, reinforcement learning–driven reasoning, and agentic or tool-augmented reasoning. We further distinguish reasoning-specific methods from vision–language models that provide semantic alignment, generation, or grounding foundations but do not themselves demonstrate multi-step inference. Across urban analysis, disaster assessment, environmental monitoring, and spatiotemporal question answering, we identify the conditions under which reasoning may add value while separating benchmark capability from validated operational deployment. Our synthesis exposes four persistent limitations: frequent use of synthetic supervision with unevenly reported provenance, outcome-dominant evaluation, weak verification of cross-modal evidence, and fragile long-horizon tool use. We therefore outline a research agenda centered on geography-aware process supervision, multimodal constraint checking, calibrated uncertainty, expert feedback, and robustness tests across sensors, regions, and time. For convenient reference and further research, we maintain a curated collection of related resources at https://github.com/ML4Sustain/Awesome-RS-Reasoning-Models.

Abstract: Improper management of domestic organic solid waste (DOSW) poses an environmental challenge, and composting offers a low-cost valorization alternative, though the effect of substrate composition and microbial inoculation on process performance remains unclear. This study evaluated the effect of substrate composition and lactic acid bacteria inoculation on the dynamics and physicochemical and microbiological quality of compost from DOSW via horizontal composting, and its agronomic performance in lettuce (Lactuca sativa L.). A completely randomized design with four treatments (T0: 100% DOSW; T1: 50% DOSW + 50% rice husk + bacteria; T2: 75% DOSW + 25% rice husk + bacteria; T3: 100% DOSW + bacteria) and three replicates ran 103 days, monitoring temperature, moisture, pH, color, and odor; final compost was characterized per NTC 5167 and evaluated for effects on lettuce growth and soil. No treatment reached a thermophilic phase, though rice husk improved porosity and reduced odor persistence. All composts were free of Salmonella spp. and enterobacteria, meeting safety criteria. T2 showed the best balance of stability, microbiological activity, and nutritional quality, while inoculation did not improve lettuce yield, with T0 yielding the highest biomass. Findings confirm horizontal composting of DOSW with structuring materials is a viable, safe, low-cost alternative.

Abstract: Whether the European Union Emissions Trading System has influenced the composition of electricity generation remains contested, and the evidence rests largely on aggregate European time series in which carbon prices and clean energy indicators rise together. We show that this design cannot separate a price effect from a common trend: in EU-27 data for 2005–2024, a linear time trend alone accounts for 98 per cent of the variation in renewable electricity, and the allowance price loses all explanatory power once a trend is included. We therefore construct a panel of the 27 Member States over 2005–2024 and identify the effect of carbon pricing from differential exposure, interacting the common allowance price with national fossil generation shares measured over 2000–2004, before the system existed. Three results follow. Carbon cost pressure displaces coal: a one-euro increase in the allowance price reduces the coal share of generation by 0.138 percentage points per unit of pre-ETS coal exposure, and this estimate is robust to country-specific linear trends. The effect is fuel-specific, operating through coal exposure but not gas exposure, as the difference in carbon content implies. Carbon pricing has no detectable effect on renewable deployment; the estimate is a precise null that excludes effects of more than roughly ±0.15 percentage points. Finally, the coal effect is conditional on the policy framework: it is −0.200 in Member States that had adopted a national phase-out commitment by 2019 and statistically indistinguishable from zero elsewhere, with the difference significant at conventional levels. Carbon pricing and phase-out commitments appear to function as complements rather than substitutes, with direct implications for the design of price floors and the extension of emissions trading to jurisdictions without national exit trajectories.

Abstract: Urban cycling is promoted as a sustainable transport mode and a means of increasing daily physical activity, but increased inhalation of fine particulate matter (PM_2.5) may offset its health benefits. This secondary, scenario-based analysis assessed the balance between physical-activity benefits and PM_2.5-related risks under real-world conditions in Gliwice, Poland. Personal PM2.5 exposure was measured during 162 trips by two com-muters in heating and non-heating seasons using low-cost sensors. Each trip duration was treated as a hypothetical habitual pattern repeated five days per week. Inhaled doses were estimated using measured concentrations, trip duration, and cycling-specific ven-tilation rates. Median cycling duration was 33.0 min/day. Inhaled dose depended on personal exposure, cycling duration, and pulmonary ventilation rather than PM_2.5 con-centration alone. The median physical-activity relative risk was 0.836, corresponding to a 16.4% reduction in all-cause mortality risk, whereas the median PM2.5-related relative risk was 1.00182, equivalent to a 0.182% increase. The combined median net relative risk was 0.840 (IQR: 0.815–0.879), indicating a 16.0% net risk reduction. All trips showed a net benefit under central assumptions, and benefits remained for 160 of 162 trips in sensitivity analysis. These findings support urban cycling promotion alongside measures to reduce cyclists’ exposure.

Abstract: This article presents preliminary results from a geoarchaeological and geomorphological investigation of Amazigh agricultural landscapes in the western Anti Atlas (Morocco). Fieldwork followed two main survey transects across contrasting physiographic units, including external plateaus, synclinal depressions, the Kerdous inlier, and spring fed inner oases. The survey documented a wide range of landesque and associated agrarian features, including agricultural terraces, check dams, cisterns, threshing platforms, settlements, and fortified collective granaries (igoudar). Their distribution shows a strong relationship with geology, slope morphology, sediment availability, water circulation, and settlement organisation. On plateaus and synclines, agrarian structures are closely associated with igoudar, settlements, runoff control, and crop processing areas. Within the Kerdous inlier, extensive terracing occurs across rugged slopes, while inner oases combine spring fed agroforestry on valley floors with dense terracing along basin margins. These results suggest that the western Anti Atlas should be understood as a long term engineered socio ecological landscape shaped by Amazigh collective strategies for soil conservation, water management, cultivation, storage, and territorial protection.

Abstract: This systematic review, conducted following PRISMA 2020 guidelines, examines satellite remote sensing approaches used to monitor vegetation responses to climate change between 2000 and 2025. Of 757 peer-reviewed studies identified, 455 (60.1%) were available as open-access full text and were extracted using a deterministic, fully auditable regular-expression pipeline; the remaining 302 could be characterised only bibliographically and are excluded from the methodological denominators reported here. Output grew steeply after 2019, with 2021-2025 accounting for 480 studies (63.4%). Landsat (51.4% of full-text studies), the Moderate Resolution Imaging Spectroradiometer (44.6%) and Sentinel-2 (43.5%) dominated; 29.9% used synthetic aperture radar and 62.9% combined two or more sensor families. The Normalised Difference Vegetation Index remained the reference index (76.9%), ahead of the Enhanced Vegetation Index (28.1%), while solar-induced fluorescence appeared in only 4.0%. Random Forest (35.8%) and linear regression (29.5%) were the most common analytical methods; deep learning rose from absent before 2020 to 18.0% of studies published in 2023-2025. First-author institutions were split almost evenly between the Global North (52.4%) and Global South (47.6%), but the latter is dominated by one country: China contributed 208 studies (27.5%) against 152 (20.1%) for all other Global South countries combined. Drylands, shrublands and peatlands were markedly under-represented relative to their global extent. Validation reporting was incomplete, with the coefficient of determination given in 40.9% of full-text studies (within-study median 0.71). Only 8.8% provided a public code repository. The review identifies research gaps and priorities for multi-sensor integration, methodological standardisation, and reproducible practice.

Abstract: The Northern Tianshan Urban Agglomeration (NTUA) in Xinjiang, China, represents a globally distinctive arid-region air-pollution system where the interaction of mountain–valley meteorology, Central Asian dust transport, and intensive industrial and residential emissions produces a complex multi-pollutant environment. This review synthesizes research progress over the past fifteen years on the atmospheric environment of the NTUA, covering ozone, particulate matter (PM2.5 and PM10), brown carbon, black carbon, dust aerosols, volatile organic compounds (VOCs), nitrogen oxides (NOx), free radicals, and reactive oxygen species. We examine spatiotemporal distribution patterns, chemical speciation, source apportionment, photochemical transformation pathways, and health risk implications across the three NTUA sub-clusters (Urumqi–Changji–Shihezi–Wujiaqu, Kuitun–Dushanzi–Wusu, and Karamay). The evidence reveals a progressive seasonal transition from dust-dominated coarse-mode aerosol loading in spring to secondary inorganic and carbonaceous fine-mode dominance in winter, with ozone formation controlled by a regime shift from VOC-limited winter conditions to NOx-limited summer photochemistry. Carbonaceous aerosols exhibit contrastive source patterns: black carbon is dominated by local fossil-fuel combustion, while brown carbon shifts from primary biomass-burning sources in winter to secondary photochemical formation in summer. The atmospheric oxidation capacity, although poorly constrained due to the absence of direct radical measurements, is shaped by the interplay of photolytic initiation, VOC–NOx chain propagation, and dust-surface heterogeneous termination. Health risk assessments indicate that the combined PM2.5–ozone–dust exposure burden produces a multi-pollutant health risk profile that single-pollutant epidemiological models cannot adequately capture. Critical research gaps include the absence of direct radical and ROS measurements, the lack of emission inventories that resolve dust–anthropogenic pollutant interactions, and the need for long-term cohort studies specific to the arid-region pollution mixture. We propose a prioritized research agenda centered on integrated observational and modeling frameworks that simultaneously constrain the dust–anthropogenic mixing state, the radical-mediated oxidation capacity, and the multi-pollutant health exposure pathway.

Abstract: Afforestation is widely used to restore degraded Mediterranean landscapes, yet restoration success is often evaluated using vegetation establishment or soil carbon accumulation, with less attention to belowground ecosystem functioning. We assessed whether Cedrus libani afforestation promotes soil functional recovery in degraded Mediterranean karst and whether structural and microbial indicators provide robust measures of restoration progress under edaphic heterogeneity. Topsoil (0–10 cm) was sampled from degraded non-afforested reference land and 10-, 15-, and 25-year-old plantations in southern Türkiye. Soil organic carbon (SOC), total nitrogen (TN), aggregate stability, microbial biomass carbon (MBC), basal respiration, microbial quotient (qMic), and metabolic quotient (qCO₂) were determined. Afforested soils had higher SOC (1.55% vs. 2.37–3.35%), TN (0.053% vs. 0.087–0.190%), aggregate stability (61.3% vs. 77.8–84.9%), and MBC (180 vs. 288–536 µg g⁻¹), whereas basal respiration declined from 0.96 to 0.30–0.36 µg CO₂–C g⁻¹ h⁻¹ and qCO₂ from 5.41 to 0.54–1.39. qMic did not differ significantly among chronosequence classes. MBC was strongly associated with SOC (ρ = 0.917, P < 0.001) but not with basal respiration (ρ = −0.075, P = 0.57). Sensitivity analyses accounting for carbonate content and pH showed that aggregate stability, basal respiration, and qCO₂ were comparatively robust, whereas SOC, TN, and MBC responses were partly substrate-dependent. Multivariate analyses revealed coordinated but non-monotonic shifts across the chronosequence. These findings indicate that restoration outcomes in Mediterranean karst cannot be assessed from carbon accumulation alone and that integrating microbial metabolic and structural indicators with edaphic information provides a more informative framework for monitoring afforestation success.

Abstract: Coarse cereals are indispensable to both national food security and the implementation of the Healthy China Initiative, underscoring the urgent need to promote their green and lowcarbon production. Using panel data from Shanxi Province spanning 2010–2020, this study first employed water footprint (WF) and carbon footprint (CF) accounting methods, together with a coupling coordination degree (CCD) model, to characterize the spatiotemporal dynamics of WF, CF, and their CCD for six major coarse cereal crops across the province. On this basis, the entropyweighted TOPSIS model was applied to assess the spatiotemporal patterns of comprehensive production potential (CPP), while exploratory spatial data analysis (ESDA) was used to detect spatial autocorrelation. Subsequently, path analysis was conducted to identify the key determinants of CPP. The results indicated that: (1) both total WF and CF per unit yield exhibited declining trends with pronounced spatial heterogeneity, generally higher in northern Shanxi, relatively balanced in the central region, and lower in the south. (2) the CCD between WF and CF showed a sustained upward trajectory over the study period.(3) the CPP of all selected coarse cereal crops increased significantly. and (4) effective irrigated area exerted the strongest positive effect on CPP, whereas the net application rate of agricultural chemical fertilizers and the proportion of leguminous coarse cereals imposed notable negative effects. Accordingly, we propose the following targeted strategies: expanding watersaving effective irrigated areas steadily, strictly curbing fertilizer overuse, tailoring dominant coarse cereal varieties to local agroecological conditions, and optimizing the regionspecific development of characteristic coarse cereals.

Abstract: Atmospheric blocking is a major feature of mid-latitude circulation and is closely associ-ated with the occurrence of extreme weather events over Europe. Among the different blocking regimes, Omega blocks are characterized by their persistent tripolar structure, which favors the development of prolonged heatwaves. In late June 2026, Western Eu-rope experienced one of the earliest and most intense heatwaves of recent decades. This study investigates the synoptic, dynamical, and climatic mechanisms associated with this event using ERA5 reanalysis data. The evolution of the 500 hPa geopotential height, 850 hPa temperature, polar jet stream, Rossby wave breaking, and dynamical tropopause (2 PVU) was analyzed together with anomalies in sea surface temperature (SST), meridional temperature gradient, soil moisture, and sensible heat flux. The results show that the heatwave developed under a persistent Omega blocking pattern, which promoted strong subsidence, enhanced solar heating, and sustained warm air advection over Western Europe. The event was further amplified by land–atmosphere feedbacks associated with anomalously dry soils. In addition, a pronounced cold SST anomaly over the subpolar North Atlantic preceded the onset of the blocking and coincided with a weakened me-ridional temperature gradient and reduced lower-tropospheric baroclinicity along the climatological position of the polar jet stream. These findings are consistent with recent studies suggesting that North Atlantic cooling associated with a weakened Atlantic Me-ridional Overturning Circulation (AMOC) may create favorable conditions for persistent summer Omega blocking and associated European heatwaves.

Abstract: The north-eastern hilly region of Bangladesh is characterized by subtropical evergreen hilly forests, haors, tea estates, and nationally designated protected areas, and is undergoing rapid land-use transformation. This study analyzes spatiotemporal changes in land use and land cover (LULC) in Moulvibazar and Habiganj districts of Bangladesh over three decades (1994-2024) using Landsat imagery and supervised Maximum Likelihood Classification in QGIS and predicts future LULC for 2054 using the Cellular Automata-Artificial Neural Network (CA-ANN) model in the MOLUSCE (Modules for Land Use Change Evaluation) plugin. Five major land cover classes were examined: croplands, water bodies, forests, tea gardens, and settlements. Croplands declined substantially from 379,716.66 ha (72.07%) in 1994 to 303,873.97 ha (57.68%) in 2024, a net loss of 14.40%. Tea gardens nearly doubled, expanding from 28,523.84 ha (5.41%) in 1994 to 69,600.19 ha (13.21%) in 2024. Forests initially declined by 1.33% between 1994 and 2004; however, then subsequently recovered, with a net gain of 4.46% by 2024. Settlement areas expanded from 17,103.54 ha (3.25%) to 26,795.58 ha (5.09%), indicating ongoing urbanization. NDVI indicates improved vegetation health, while the NDWI indicates surface water fluctuation. The projections indicate continued tea garden and settlement expansion alongside further cropland and forest cover decline, emphasizing the need for sustainable cropland management and long-term forest management to ensure ecological sustainability in this region.

Abstract: Silica aerogels are among the most extraordinary porous materials produced through sol–gel chemistry, distinguished by ultralow density, exceptionally high porosity, large specific surface area, and extremely low thermal conductivity. Despite these characteristics, widespread application of conventional silica aerogels has been constrained by inherent brittleness, poor mechanical strength, and moisture sensitivity. Significant research has therefore focused on silica aerogel composites, in which reinforcing or functional phases — fibers, polymers, carbon nanomaterials, metal oxides, and biopolymers — are integrated into the silica network to enhance mechanical robustness, flexibility, hydrothermal stability, electrical conductivity, catalytic activity, and multifunctionality while largely preserving the parent aerogel's desirable properties. This chapter reviews the synthesis, characterization, properties, and applications of silica aerogel composites. Sol–gel processing and drying technologies are discussed, followed by composite-formation strategies and the advanced techniques used to evaluate structural, mechanical, thermal, surface, and functional properties. The effects of reinforcing phases on mechanical performance, thermal conductivity, and hydrothermal stability are analyzed, and current and emerging applications in thermal insulation, environmental remediation, catalysis, acoustic damping, aerospace systems, biomedical engineering, and energy storage are highlighted. Finally, key challenges and future directions involving multifunctional materials, green synthesis, and data-driven materials design are discussed.

Abstract:

Background: Urban Green Spaces (UGS) are vital for urban sustainability, providing ecological, environmental, and social benefits. Growing urbanisation, climate change, and biodiversity loss highlight the need for better integration of ecological principles into planning. However, existing approaches are fragmented and poorly capture hierarchical relationships between urban form, ecological processes, and ecosystem outcomes. Methods: This review synthesises interdisciplinary research from urban ecology, landscape ecology, urban forestry, ecosystem services, and spatial planning. It introduces the Integrated Ecological Framework of Urban Green Spaces (IEF–UGS), structured into six levels: urban morphology, green infrastructure, ecological processes, ecological functions, ecosystem services, and urban resilience. Results: Urban morphology is identified as the key structural driver shaping ecological functioning via habitat configuration, connectivity, hydrology, and microclimate. Green infrastructure forms the spatial basis for ecological processes, which generate functions supporting ecosystem services and resilience. The framework clarifies causal links across levels and resolves conceptual inconsistencies in prior research. Conclusions: IEF–UGS offers both theoretical and practical value, supporting ecological assessment, green infrastructure planning, urban forest management, and climate adaptation. It enables integrated indicators and improves evidence-based decision-making, providing a robust foundation for future research on sustainable urban systems.

Abstract: Private forest land-use designations can contribute to climate mitigation; however, their carbon benefits are difficult to estimate because protected and less strictly regulated forest lands often differ in site and environmental conditions. Evidence on whether designation-associated carbon differences vary with forest structure is also limited. This study evaluated carbon stock differentials between protected areas in private forests (PA) and matched semi-conservation mountainous districts (SCA) in South Korea using the InVEST Carbon Storage and Sequestration model. Propensity score matching was used to improve comparability, followed by average treatment effect on the treated (ATT) estimation and regression analysis of the matched sample. Alternative matching and regression specifications were examined as robustness checks. The mean carbon stock was 4.97 Mg C ha⁻¹ higher in PAs than in comparable SCAs (95% CI: 4.45–5.49, p < 0.001). The PA-SCA difference varied by forest structure: it was greater in broad-leaved forests than in coniferous forests, showed a nonlinear pattern across canopy density classes, and declined with increasing age class. These findings indicate that carbon stock differences associated with private forest land-use designation are structurally heterogeneous. While they should be interpreted as cross-sectional associations, they provide evidence for differentiated land-management, compensation, and conservation prioritization strategies.

Abstract: Increasing reliance on groundwater, declining water tables and saltwater intrusion have intensified water stress along the coastal regions. This study evaluates the availability of source water for Managed Aquifer Recharge (MAR) in the Tiwi coastal aquifer, Kenya. Runoff, as a key potential source for artificial recharge, was quantified for the Pemba–Shimbo and Kongo/Mwachema watersheds using the Soil Conservation Service Curve Number (SCS-CN) method within a Geographic Information System (GIS) environment. Ten years (2015–2024) of rainfall data from three meteorological stations were spatially distributed using the Thiessen polygon method, while land use and soil characteristics informed curve number estimation under varying antecedent moisture conditions. Results indicate that excess runoff and thus potential recharge water is highly seasonal, occurring mainly during the long and short rainy seasons (March–May and October–December). The Pemba–Shimbo watershed exhibited significantly higher recharge potential, with runoff volumes ranging from 0.1 to 77.7 million cubic meters (MCM), compared to 0.1 to 5.5 MCM in Kongo/Mwachema. On average, approximately 13 MCM and 0.7 MCM of water were available annually for recharge in Pemba–Shimbo and Kongo/Mwachema, respectively. The findings demonstrate substantial, yet underutilized, opportunities for MAR, particularly in larger catchments. Strategic planning, including real-time flow monitoring and integration of weather forecasts, is recommended to optimize recharge interventions and enhance groundwater sustainability under changing climatic conditions.