In post-fire environments, non-native species plantations can significantly affect community dynamics, including species composition, diversity, and ecosystem processes. Long-term studies are essential to assess stand invasiveness, the persistence of planted species, and the re-establishment of native species. This study examines Eucalyptus camaldulensis (River red gum), Pinus pinea (Stone pine), and Pinus brutia (Turkish red pine) plantations in post-fire P. brutia forests in Turkey by assessing the vegetation characteristics and soil properties, as well as the allelopathic effects of these species on the seed germination and seedling development of P. brutia. A total of 17 woody taxa were recorded across three types of plantation sites. The E. camaldulensis stand had the highest species richness (14 species), followed by the P. brutia and P. pinea stands (10 and 9 species, respectively). An 11-year monitoring study of tree canopy cover in plantation forests revealed that P. brutia successfully colonized and expanded its canopy cover within the E. camaldulensis stand. In contrast, P. brutia entered and later established in the P. pinea stand. Leaf extract and soil experiments to detect the potential allelopathic effects of E. camaldulensis and P. pinea indicated that, unlike the inhibitory effects observed in P. pinea, E. camaldulensis may promote P. brutia seed germination. Regarding soil properties, the E. camaldulensis stand showed higher cation exchange capacity, electrical conductivity, organic matter content, and nutrient availability than the other stands. In conclusion, our findings demonstrate that P. brutia has a high potential to re-colonize areas afforested with other species after a fire, and the time required for its re-colonization depends on the facilitating or inhibiting effect created by other species, the size of the plantation stand, and the distance to the P. brutia stands.
Forests play a crucial role in regulating global atmospheric carbon and provide multiple ecosystem services. Forest management currently faces two major global challenges: climate change and biodiversity loss. Management strategies such as forest protection (PRO), sustainable management (MAN), and restoration (RES) - key elements of Nature-based Solutions - must therefore promote both carbon storage and sequestration while conserving biodiversity and maintaining ecosystem integrity. In this study, we evaluated these three forest management systems in the Southern Andean Yungas (SAY) of northern Argentina. We characterized carbon storage across different pools, as well as species richness, biodiversity, and structural attributes, and analyzed the relationships among these variables. Our results indicate a clear decoupling between species richness and carbon storage (ρ = 0.30; p = 0.16). The three forest sites exhibited distinct characteristics. Compared to the MAN and RES sites, PRO stored 150% and 73% more total carbon, respectively, concentrated mainly in the aboveground biomass of adult trees. Although PRO had lower richness than the other sites, it best represented the late-successional community, with the highest proportion of climax species (86%) and higher average structural values (DBH and height). These findings suggest that carbon stabilization in SAY is driven more by functional identity and structural maturity than by simple species counts. Furthermore, our results indicate that the efficiency of forest protection as an NbS lies in its capacity to maintain a mature forest structure that could potentially regulate soil microclimates and slow organic matter turnover. We also identified native species with potential “carbon-ecological benefits” for the region. Based on management and restoration practices to date, forest protection is the most effective NbS for long-term carbon retention and biodiversity conservation in subtropical montane forests.
In this study, the response of Eucalyptus grandis seedlings to varied water availability and potassium fertilization in coarse-textured soil was investigated. The experiment took place in a greenhouse in Buenos Aires, Argentina, over 56 days, with 15 replicates for each treatment. We maintained pots in the non-water-limited group at field capacity (FC), while those in the water-restricted group were maintained at 40% FC. Each water regime received one of three potassium levels (K1, K2, and K3). We measured plant height and root-collar diameter periodically. At the end of the experiment, biomass allocation among plant parts was quantified. We also evaluated physiological traits by measuring stomatal conductance and relative water content (RWC). The results show that potassium fertilization did not improve seedling performance under water stress or enhance growth in well-watered seedlings. Water restriction was the main limiting factor. Keeping soil moisture at 40% of FC reduced height growth, root-collar diameter, biomass, and leaf area. It also negatively affected physiological traits such as stomatal conductance and RWC, but did not cause seedling mortality.
Salinity is a growing global concern, aggravated by climate change and human activities, with severe impacts on forests and biodiversity. This review critically examines the following key points: (1) the systematic impacts of salinity on forestry and ecosystem functioning; (2) the multilevel mechanistic responses of Eucalyptus species, clones, and genotypes, emphasizing their operational deployment in salt-affected landscapes; and (3) the potential of contemporary genetic technologies and environmental strategies to enhance plant resistance. Although responses vary among taxa, salinity tolerance is generally mediated through an integrated physiological and molecular framework, and substantial intra- and interspecific variation offers a solid foundation for targeted selection, hybridization, and genetic improvement. While genetic transformation and large-scale application of omics approaches remain technically challenging, recent advancements in breeding and management practices provide effective pathways for developing salt-tolerant planting material. Importantly, most current knowledge comes from controlled studies on juvenile material, highlighting the need for long-term field validation. Despite this limitation, the Eucalyptus genus represents a strategic resource for afforestation, reforestation, and ecological restoration of salinity-affected regions. Future research should prioritize field-level validation, genotype-environment interactions, and translating molecular insights into scalable silvicultural practices that strengthen forest resilience under increasing salinity stress.
Leaf area index (LAI) provides crucial insights into forest canopy structure, vegetation density, and overall ecosystem functioning. In the Zagros Mountains of northwestern Iran, traditional silvopastoral practices rely on tree foliage as animal fodder for local communities. Understanding and estimating LAI in these forests can therefore support the adoption of appropriate strategies for sustainable management. This study aims to map LAI in the Zagros semi-Mediterranean Forests (ZMFs) in Iran using Machine Learning Regression Algorithms (MLRAs) combined with Sentinel-2 (S-2) data and a Digital Elevation Model (DEM). We employed three MLRAs, i.e., Support Vector Regression (SVR), K-Nearest Neighbors (KNN), and Random Forest (RF). To train and evaluate the algorithms’ performance, in situ LAI data were collected in 60 field plots measuring 20×20 m. The results revealed that the RF algorithm performed best, with R2 = 0.82, RMSE = 0.16 m2 m-2, and rRMSE = 16.84. We further cross-compared the generated LAI map with three satellite-derived LAI products: Sentinel-2 SNAP, MODIS, and PROBA-V. The results indicated that the uncertainty of global LAI products varies from 30% to 55% higher than that of our applied approach. The study concludes that integrating S-2 data with DEM and MLRAs provides an accurate and reliable method for mapping LAI in open-canopy ZMFs. However, global LAI products show higher uncertainty because of lower spatial resolution and the lack of suitable empirical transfer functions for these forest types.
