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Current advancements on photogrammetric software along with affordability and wide spreading of Unmanned Aerial Vehicles (UAV), allow for rapid, timely and accurate 3D modelling and mapping of small to medium sized areas. Although the importance and applications of large format aerial overlaps cameras and photographs in Digital Surface Model (DSM) production and LIDAR data is well documented in literature, this is not the case for UAV photography. Additionally, the main disadvantage of photogrammetry is the inability to map the dead ground (terrain), when we deal with areas that include vegetation. This paper assesses the use of near-infrared imagery captured by small UAV platforms to automatically remove vegetation from Digital Surface Models (DSMs) and obtain a Digital Terrain Model (DTM). Two areas were tested, based on the availability of ground reference points, both under trees and among vegetation, as well as on terrain. In addition, RGB and near-infrared UAV photography was captured and processed using Structure from Motion (SfM) and Multi View Stereo (MVS) algorithms to generate DSMs and corresponding colour and NIR orthoimages with 0.2 m and 0.25 m as pixel size respectively for the two test sites. Moreover, orthophotos were used to eliminate the vegetation from the DSMs using NDVI index, thresholding and masking. Following that, different interpolation algorithms, according to the test sites, were applied to fill in the gaps and created DTMs. Finally, a statistic analysis was made using reference terrain points captured on field, both on dead ground and under vegetation to evaluate the accuracy of the whole process and assess the overall accuracy of the derived DTMs in contrast with the DSMs.

In south China, eucalyptus plantations typically consist of a single-species overstory (a eucalyptus monoculture) and a dense understory of a dominant fern species. In the current study, we assessed the effects of four treatments [control (CK), understory removal (UR), tree removal (TR), and all-plant removal (PR)] on the abundances of soil nematode genera, which can provide insight into the ecological functions of understory plants and trees. Soil nematodes were sampled six times (once before and five times after treatments were implemented) at 0–5 and 5–10 cm soil depths. The temporal dynamics of nematode genera were analyzed by the principle response curves (PRC) method. At 0–5 cm depth, the abundances of most nematode genera rapidly increased shortly after vegetation removal but then gradually decreased; the effects of UR were stronger than the effects of TR. The results might be explained by the pulsed input of plant debris to soil and its subsequent depletion. At 5–10 cm depth, the nematode communities were relatively unaffected by vegetation removal within the first 162 days, but the abundances of most genera sharply decreased on day 258 and then sharply increased on day 379 (the last sampling time). The results indicated that most nematode genera, even r -selected genera, were sensitive to vegetation removal in the upper soil layer and that understory vegetation can greatly affect soil nematode communities and presumably soil food webs. The nematode genera Prismatolaimus and Diphtherophora may be good indicators of the effects of vegetation removal. The results increase our understanding of the relationships between soil nematode genera and forest plant communities and of how soil biota is affected by forest management practices.

The increase in nitrogen (N) deposition may affect nitrous oxide (N₂O) emission in boreal peatlands by increasing N availability and/or altering vegetation composition. However, the effects of changes in vegetation composition (due to the increase in N deposition) on N₂O emission are still unknown. Therefore, we used a factorial design, comprising the removal of plant functional groups and N fertilization to investigate their independent effects and combined effects on N₂O fluxes at an ombrotrophic blanket bog in Western Newfoundland, Canada. The results reveal that N₂O emission significantly increased with N fertilization. Notably, the effect of N addition on N₂O fluxes was modulated by the removal of graminoids. In particular, the removal of graminoids reduced 69% of the N₂O emission increases due to N fertilization in the third year of the experiment. This result suggests that the enhancement of graminoid abundance due to increases in N deposition/fertilization may dramatically increase N₂O emissions in boreal peatlands leading to stronger impacts on the global climate and stratospheric ozone depletion in the future if no countermeasures to reduce reactive N emission are undertaken.

Increased clouds and precipitation normally decrease the diurnal temperature range (DTR) and thus have commonly been offered as explanation for the trend of reduced DTR observed for many land areas over the last several decades. Observations show, however, that the DTR was reduced most in dry regions and especially in the West African Sahel during a period of unprecedented drought. Furthermore, the negative trend of DTR in the Sahel appears to have stopped and may have reversed after the rainfall began to recover. This study develops a hypothesis with climate model sensitivity studies showing that either a reduction in vegetation cover or a reduction in soil emissivity would reduce the DTR by increasing nighttime temperature through increased soil heating and reduced outgoing longwave radiation. Consistent with empirical analyses of observational data, our results suggest that vegetation removal and soil aridation would act to reduce the DTR during periods of drought and human mismanagement over semiarid regions such as the Sahel and to increase the DTR with more rainfall and better human management. Other mechanisms with similar effects on surface energy balance, such as increased nighttime downward longwave radiation due to increased greenhouse gases, aerosols, and clouds, would also be expected to have a larger impact on DTR over drier regions.

Background Lead‐related infective endocarditis is a serious complication of implantable cardioverter‐defibrillators (ICDs), especially in patients with advanced heart failure who are poor surgical candidates. Management of large lead‐associated vegetations remains a clinical challenge. Methods We present the case of a 54‐year‐old woman with ischemic cardiomyopathy and recurrent ICD complications who developed bacteremia and infective endocarditis with vegetations on the aortic valve and a 1.5 × 1.3 cm mass on the right ventricular lead. Given her poor surgical candidacy due to worsening heart failure, a percutaneous approach was pursued. Results The patient underwent successful intracardiac echocardiography (ICE)‐guided catheter‐based vegetation removal using a vacuum‐assisted aspiration system, followed by transvenous lead extraction. The procedure was well tolerated, and the patient demonstrated clinical improvement post intervention. Conclusions This case illustrates the utility of ICE‐guided percutaneous aspiration and lead extraction for managing large lead‐related vegetations in patients with infective endocarditis who are not candidates for surgery. Lead‐related infective endocarditis (LRIE) with large vegetations represents a common and challenging complication in patients with implantable cardioverter‐defibrillators who are not surgical candidates due to the high prevalence of comorbid conditions. This case demonstrates successful management using intracardiac echocardiography (ICE)‐guided percutaneous aspiration with a vacuum‐assisted system, followed by transvenous lead extraction, achieving clinical improvement without surgery. The technique highlights ICE as a critical tool for real‐time visualization and guidance during catheter‐based vegetation removal in high‐risk patients.

Background With appropriate management, based on vegetation removal that reverses late-successional vegetation stages, roadsides can support high levels of biodiversity. However, current recommendations for roadside management to conserve or restore biodiversity are largely based on research on non-roadside grassland habitats, and much of the evidence on how roadside management practices affect biodiversity is found in non-peer-reviewed grey literature. Therefore, based on suggestions from key stakeholders and an initial systematic map that identified 97 studies on how biodiversity is affected by vegetation removal on roadsides, we conducted a full systematic review of the effects on plant and invertebrate diversity of disturbance-based maintenance of roadsides. Methods The review was restricted to effects of non-chemical interventions such as mowing, burning, grazing and mechanical shrub removal. Studies were selected from the systematic map and from an updated search for more recent literature using a priori eligibility criteria. Relevant articles were subject to critical appraisal of clarity and susceptibility to bias, and studies with low or unclear validity were excluded from the review. Data on species richness, species diversity and abundance of functional groups were extracted together with metadata on site properties and other potential effect modifiers. Results from the 54 included studies were summarised in a narrative synthesis, and impacts of mowing practices on the total species richness and diversity of plants and on the abundance of forbs, graminoids and woody plants were quantitatively analysed using t tests of study-level effect ratios. Results Nearly all of the 54 studies included in the review were conducted in Europe (29) or North America (24). The vast majority of studies (48) examined impacts of mowing. Effects on vascular plants were reported in 51 studies, whereas 8 of the studies reported on invertebrates. Quantitative analysis of plant species richness and species diversity showed that mowing effects were dependent on the interplay between mowing frequency and hay removal. Thus, there were no statistically significant overall effects of mowing vs. no mowing, frequency of mowing, timing of mowing or hay removal. However, species richness was higher in roadsides mowed once or twice per year with hay removal than in unmown roadsides, and positively affected by mowing twice compared to once per year. Similar, but less pronounced, effects were found for plant species diversity. In addition, mowing had a negative impact on woody plant abundance, and increased mowing frequency had a negative impact on graminoid abundance. The few studies on invertebrates showed effects that diverged across taxon groups, and there was not enough data for quantitative analysis of these results. Conclusions The results provide evidence on the effects of mowing on plant species richness. To increase plant species richness, roadsides should be mowed each year, preferably twice per year, and hay should be removed after each cutting. The review also identifies large knowledge gaps concerning roadside management and its effects on biodiversity, especially regarding invertebrates. Hence, this systematic review provides not only a valuable basis for evidence-based management but also guidance for future research on this topic, essential to inform management of road networks for biodiversity conservation.

Epixylic vegetation may be important in dead wood decay by altering the microenvironment and, thereby, microbial communities in logs. However, the interaction between epixylic vegetation and dead wood microbial communities remains poorly known. Therefore, repeated experimental epixylic (bryophyte-dominated) vegetation removal (ERM) from logs of the fir Abies faxoniana across a wide range of decay classes (I–V) was conducted on the eastern Tibetan Plateau. The dynamics of the microbial community were separately measured in heartwood, sapwood and bark using the phospholipid fatty acid analysis (PLFA) method. Our results showed that the effects of ERM on the microbial community depended greatly on the three log components and sampling seasons but less on decay class. (1) The absence of epixylic vegetation generally enhanced the total microbial biomass and Sørensen similarity in bark, whereas it had a more complicated effect on those in heartwood and sapwood. Specifically, the response to ERM became progressively stronger from winter until the late growing season. (2) ERM increased the total percentage of Gram-negative bacteria and fungi in heartwood and upper side sapwood and decreased their percentages in bark. (3) The moisture content and pH of the logs were good predictors and likely drivers of the dynamic patterns of the microbial community composition. Our findings demonstrate strong and partly consistent interactions between epixylic vegetation and microbial communities. Further in-depth research should reveal how these interactions feed back to the decomposition process of logs and thereby to carbon and nutrient cycles in the alpine forest ecosystem.

The Great Wall of China, one of the nation’s most remarkable military defense structures, possesses a history spanning several millennia and is associated with numerous heritage sites. Today, it stands as a world-renowned cultural heritage asset. Vegetation growing on the ruins of the Great Wall can exert both detrimental and protective effects on the structure. Indiscriminate removal of such vegetation may lead to unintended damage to the heritage site. Drawing on the theory of “evaluative conservation”, this study integrates the analytic hierarchy process (AHP) and the Delphi method to develop a resistance assessment system for vegetation removal. A case study was conducted on 40 plant species or categories located along the Ming-era Guangwu section of the Great Wall, with spatial zoning analysis applied to inform removal strategies. The results reveal the structure, key factors, and classification criteria of the resistance evaluation system. Corresponding management recommendations are proposed, including strategies such as “preservation”, “partial preservation”, “removal”, and “subsequent removal and management”. This research provides a foundational reference for the conservation and restoration of the Great Wall heritage, and for the management of associated vegetation.

PurposeTo perform a systematic review of reports in which the AngioVac™ percutaneous vacuum-assisted aspiration system was successfully used to debulk or remove vegetations prior to percutaneous lead extraction.MethodsWe included all studies and case reports that used a percutaneous aspiration technique for vegetation removal or debulking with percutaneous lead extraction for patients with lead-associated endocarditis. Ten reports and retrospective data from our centers were used, which included a total of 88 patients and 205 leads.ResultsThe percutaneous aspiration procedure was completely or partially successful in 86 patients (97.7%). The lead extraction procedure itself was successful in 87 patients (98.9%). The aspiration procedure and lead extraction were done concomitantly in 81 patients (92.0%). Four patients (4.5%) had major complications (two due to vascular injuries, one due to coronary sinus injury, and one due to tricuspid valve injury). There were no complications from the aspiration procedure, and no cases were associated with procedure-related mortality.ConclusionWhile patients with large vegetations have historically been referred for surgical lead extraction, data are lacking in its techniques and outcomes. Existing data suggest that percutaneous vacuum-assisted aspiration for vegetation removal or debulking in endocarditis prior to or concurrent with percutaneous lead extraction has a high success rate with a low complication rate across a broad series of patients.

The increasing pressure from agriculture and pasture activities over non-forest vegetation areas revealed the need of INPE to extend forest regular monitoring to non-forested areas. Non-forest vegetation consists of savannahs, shrub lands, grasslands or seasonal floodplains that occupy 279 thousand km2 (6,63 %) of Brazilian Amazon biome extension. Addressed ecosystem services of non-forest vegetation vary from climate, soil, carbon storage, biodiversity, water and fire regulation to cultural benefits and living of the population. The challenge in monitoring non-forest removal lies in climatic seasonality, high variability of phytophysiognomies and cloud coverage. In this work we developed a method to map non-forest vegetation from 2000 to 2021 in a pilot area enclosing five municipalities in Roraima and Amapá states. Considering the total area of 47 thousand km2, 58 % was originally forest and 37 % was non-forest vegetation. In 2020, soybean planted areas occupied 60 thousands hectares in these municipalities. We adapted PRODES protocol to non-forest features using visual interpretation of Landsat and SENTINEL-2 satellite images. Regional expertise supported the interpretation keys to distinguish non-forest removal from seasonal changes or other land use changes. A baseline map for 2000 is provided together with biannual and annual increments for 2002–2018 and 2019–2021, respectively. Results show removal of non-forested areas even overpassing deforestation in some municipalities. Accumulated non-forest removal was 3.133,06 km2 or 17,44 % of the non-forest area enclosed. This work consolidated the method to be applied in the Brazilian Amazon biome allowing a uniform historical mapping series of deforestation and non-forest removal.