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Wild boar ( Sus scrofa ) is a widespread megaherbivore that can intensively disturb large areas of its habitat both in its native and non-native ranges, when populations reach high densities. The main problem is its rooting habit, which entails intensive disturbance of the topsoil and herbaceous layer. The extent of concomitant habitat degradation varies across ecoregions; some ecosystems are rather resilient, although the damages are long-lasting in others. In mown meadows, a secondary problem is the inability to resume mowing due to the uneven soil surface of rooted patches. This can lead to both economic loss and a loss of management-dependent biodiversity. We assessed the short-term effects of rooting on vegetation cover and composition in central European permanent hay meadows and tested the utility of manual soil surface resmoothing to enable the continuation of mowing. We found that rooting increased bare soil surface but vegetation recovery occurred within a year. Similarly, high resilience was found for species composition. We could not detect any difference between rooted and intact grassland patches after 1 yr. This short-term perturbation of the composition could be associated with a temporary decrease in grassland specialist species and an increase in ruderal and pioneer species. Soil surface resmoothing was an additional disturbance, but vegetation cover returned to the level of intact grasslands within a year. Vegetation composition needed a slightly longer time (2 yr) to recover than that without resmoothing. We thus recommend the application of manual resmoothing in hay meadows with high short-term resilience to rooting, but a risk of long-term degradation (e.g., shrub encroachment) if mowing is not resumed. In hay meadows with lower resilience (because of, e.g., steep slopes), resmoothing should be applied with caution and may be supplemented with seeding to support the recovery of the vegetation and prevent soil erosion. (c) 2025 The Society for Range Management. Published by Elsevier Inc. All rights are reserved, including

期刊论文 2025-05-01 DOI: 10.1016/j.rama.2025.03.002 ISSN: 1550-7424

Major earthquakes in mountainous areas usually exert negative impacts on vegetation cover and growth due the numerous coseismic landslides. However, understanding of the duration of these impacts and spatiotemporal dynamics of vegetation recovery dominated by environmental factors remains limited. The present study aimed to investigate the spatiotemporal dynamics of natural vegetation restoration and associated mechanisms in a mountainous basin in southwestern China after the 2008 Wenchuan Ms 8.0 earthquake. The results showed that the normalized difference vegetation index (NDVI) substantially decreased from 0.70 to 0.47 after the earthquake and then gradually increased at an average rate of 0.020 yr(- 1). By 2023, vegetation had been restored to its pre-earthquake levels in 84.9% of the total area. And 15.1% of the land remains unrecovered, with 11.7% covered by landslide slump mass. Approximately 4.16% of the entire basin is projected to recover in the future (theta(slope) > 0, H > 0.5) over a seven-year period. Elevation was the most crucial factor influencing both the damage and recovery of vegetation in the basin, followed by landslide slump mass and soil type. The overall vegetation recovery potential is limited, with an average vegetation restoration potential index (VRPI) of 0.21 in 2023. Notably, 11.2% of the basin exhibited a VRPI > 0.4, mainly situated in the northernmost part, characterized by high altitude (> 3000 m), carbonate-cinnamon soil, and dense distribution of landslide slump mass. The results indicate that natural vegetation has a robust capacity for recovery, albeit hindered by active landslides and fragile high-altitude habitats, where human intervention should be implemented. The results provide valuable information to guide future vegetation restoration planning and layout in Wenchuan earthquake-stricken areas.

期刊论文 2025-02-01 DOI: 10.1007/s11069-024-06918-1 ISSN: 0921-030X

Wildfires could have a strong impact on tundra environment by combusting surface vegetation and soil organic matter. For surface vegetation, many years are required to recover to pre-fire level. In this paper, by using C-band (VV/HV polarization) and L-band (HH polarization) synthetic aperture radar (SAR) images acquired before and after fire from 2002 to 2016, we investigated vegetation change affected by the Anaktuvuk River Fire in Arctic tundra environment. Compared to the unburned areas, C- and L-band SAR backscatter coefficients increased by up to 5.5 and 4.4 dB in the severely burned areas after the fire. Then past 5 years following the fire, the C-band SAR backscatter differences decreased to pre-fire level between the burned and unburned areas, suggesting that vegetation coverage in burned sites had recovered to the unburned level. This duration is longer than the 3-year recovery suggested by optical-based Normalized Difference Vegetation Index (NDVI) observations. While for the L-band SAR backscatter after 10-year recovery, about 2 dB higher was still found in the severely burned area, compared to the unburned area. The increased roughness of the surface is probably the reason for such sustained differences. Our analysis implies that long records of space-borne SAR backscatter can monitor post-fire vegetation recovery in Arctic tundra environment and complement optical observations.

期刊论文 2019-10-01 DOI: 10.3390/rs11192230

Forest fires have significantly impacted the permafrost environment, and many research programs looking at this have been undertaken at higher latitudes. However, their impacts have not yet been systematically studied and evaluated in the northern part of northeast China at mid-latitudes. This study simultaneously measured ecological and geocryological changes at various sites in the boreal forest at different stages after forest fires (chronosequence approach) in the northern Da Xing'anling (Hinggan) Mountains, Northeast China. We obtained results through field investigations, monitoring and observations, remote sensing interpretations, and laboratory tests. The results show that forest fires have resulted in a decreased Normalized Difference Vegetation Index (NDVI) and soil moisture contents in the active layer, increased active layer thickness (ALT) and ground temperatures, and the release of a large amount of C and N from the soils in the active layer and at shallow depths of permafrost. NDVI and species biodiversity have gradually increased in the years since forest fires. However, the vegetation has not fully recovered to the climax community structures and functions of the boreal forest ecosystems. For example, ground temperatures, ALT, and soil C and N contents have been slowly recovering in the 30years after the forest fires, but they have not yet been restored to pre-fire levels. This study provides important scientific bases for assessment of the impacts of forest fires on the boreal forest ecosystems in permafrost regions, environmental restoration and management, and changes in the carbon stock of soils at shallow (<3m) depths in the Da Xingan'ling Mountains in northeast China.

期刊论文 2019-07-01 DOI: 10.1002/ppp.2001 ISSN: 1045-6740
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