Artykuły w czasopismach: „Vegetation removal”

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Dion, Nancy, Keith A. Hobson i Serge Larivière. "Interactive Effects of Vegetation and Predators on the Success of Natural and Simulated Nests of Grassland Songbirds". Condor 102, nr 3 (1.08.2000): 629–34. http://dx.doi.org/10.1093/condor/102.3.629.

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Abstract We examined the influence of vegetation and predator community on nesting success of songbirds in the grasslands of eastern North Dakota, USA. Each year, eight sites were chosen: four were subject to predator removal, and four were non-removal sites. On each site, nests of grassland songbirds were monitored, and simulated nests were used to examine how vegetation characteristics at nests affect nest success. Vegetative characteristics at simulated nests did not differ from those at natural nests, but successful natural nests had greater forb and lesser grass cover than unsuccessful nests, whereas no differences in vegetation were detected between successful and depredated simulated nests. On non-removal sites, small mammals and ground squirrels (Spermophilus sp.) depredated nests in taller and denser cover when compared to nests destroyed by medium-sized mammals and birds. On removal sites, we found no difference in vegetation characteristics of nests depredated by different predator types. However, each group of mammalian predators depredated simulated nests with different vegetation characteristics on removal versus non-removal sites. On sites where predators were removed, small mammals and ground squirrels preyed on simulated nests in shorter vegetation containing fewer forbs, ground squirrels preyed on nests with higher grass cover and lower vertical density, and medium-sized carnivores preyed on nests in taller vegetation. These results support the hypothesis that high predator diversity may reduce the chance of “safe” nest sites, and suggest that the behavior of low-level predators may change when top-level predators are removed.

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Paul, T. S. H., i N. J. Ledgard. "Vegetation succession associated with wilding conifer removal". New Zealand Plant Protection 62 (1.08.2009): 374–79. http://dx.doi.org/10.30843/nzpp.2009.62.4878.

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Techniques used to remove unwanted wilding conifers can impact on subsequent vegetation successions Five South Island sites were assessed for vegetation successions after conifers had been removed by four methods felled to waste mulched harvested or killed standing by stem poisoning Felled conifers created a flush of vigorous plant growth but this increase was not longlasting and the end result was reduced plant biodiversity Mulching reduced all plant cover initially but gave poor wilding control Harvesting led to a dominance of exotics including wildings whereas solely native plants were found under dead standing trees that had been poisoned Results indicated that while there were differences in vegetation composition between the low and high altitude sites there are good opportunities for manipulating wilding control towards more desirable vegetation covers particularly involving native plants

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Baugh, Calum A., Paul D. Bates, Guy Schumann i Mark A. Trigg. "SRTM vegetation removal and hydrodynamic modeling accuracy". Water Resources Research 49, nr 9 (wrzesień 2013): 5276–89. http://dx.doi.org/10.1002/wrcr.20412.

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Eckermann, Trevor K., Danielle S. Hunt i Alicia M. Kinoshita. "Impacts of Vegetation Removal on Urban Mediterranean Stream Hydrology and Hydraulics". Hydrology 9, nr 10 (29.09.2022): 170. http://dx.doi.org/10.3390/hydrology9100170.

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Given the widespread presence of non-native vegetation in urban and Mediterranean watersheds, it is important to evaluate how these sensitive ecosystems will respond to activities to manage and restore native vegetation conditions. This research focuses on Del Cerro, a tributary of the San Diego River in California, where non-native vegetation dominates the riparian zone, creating flooding and fire hazards. Field data were collected in 2018 to 2021 and consisted of water depth, streamflow, and stream temperature. Our data set also captured baseline conditions in the floodplain before and after the removal of burned non-native vegetation in November 2020. Observed changes in hydrologic and geomorphic conditions were used to parameterize and calibrate a two-dimensional hydraulic model to simulate urban floodplain hydraulics after vegetation removal. We utilized the U.S. Army Corps of Engineers’ Hydrologic Engineering Center River Assessment System (HEC-RAS) model to simulate the influence of canopy loss and vegetation disturbance and to assess the impacts of vegetation removal on stream restoration. We simulated streamflow, water depth, and flood extent for two scenarios: (1) 2019; pre-restoration where non-native vegetation dominated the riparian area, and (2) 2021; post-restoration following the removal of non-native vegetation and canopy. Flooding after restoration in 2021 was more frequent compared to 2019. We also observed similar flood extents and peak streamflow for storm events that accumulated half the amount of precipitation as pre-restoration conditions. Our results provide insight into the responses of small urban stream reaches to the removal of invasive vegetation and canopy cover.

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Bird, Tania Leah Fairfax, Amos Bouskila, Elli Groner i Pua Bar Kutiel. "Can Vegetation Removal Successfully Restore Coastal Dune Biodiversity?" Applied Sciences 10, nr 7 (28.03.2020): 2310. http://dx.doi.org/10.3390/app10072310.

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Coastal dune habitats have been declining globally over the last several decades due to rapid urbanization. Within remaining dune systems, dune fixation has resulted in further losses of mobile dunes with negative impacts on their associated species. Some studies suggest vegetation removal can initially promote habitat heterogeneity, and increase availability of suitable habitats for psammophile, xeric and endemic mobile dune species, but longer-term responses are generally unknown. We investigated the temporal trends of four taxonomic groups to determine the effect of vegetation removal on dune assemblages over a 12-year period at an LTER site. Three different forms of removal are investigated here—removal in a grid form on fixed dunes, removal of the wind-facing slope vegetation on semi-fixed dunes and opportunistic off-road driving on disturbed dunes. Results were varied across taxa, highlighting the need for multi-taxa monitoring in conservation and restoration management. Overall, fixed dune treatment had very little effect, while a stronger response was found in semi-fixed treatments in particular for mobile dune indicator species, which showed evidence of recolonization within a few years following treatment. Disturbed dunes were most similar to mobile dunes for animal taxa indicating that pulse removal may not be as effective as continuous press disturbance. Nevertheless, a less destructive form of disturbance such as re-introduction of grazing might be preferable and requires further investigation.

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Evans, Alexandra D., Kevin H. Gardner, Scott Greenwood i Brett Still. "UAV and Structure-From-Motion Photogrammetry Enhance River Restoration Monitoring: A Dam Removal Study". Drones 6, nr 5 (19.04.2022): 100. http://dx.doi.org/10.3390/drones6050100.

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Dam removal is a river restoration technique that has complex landscape-level ecological impacts. Unmanned aerial vehicles (UAVs) are emerging as tools that enable relatively affordable, repeatable, and objective ecological assessment approaches that provide a holistic perspective of restoration impacts and can inform future restoration efforts. In this work, we use a consumer-grade UAV, structure-from-motion (SfM) photogrammetry, and machine learning (ML) to evaluate geomorphic and vegetation changes pre-/post-dam removal, and discuss how the technology enhanced our monitoring of the restoration project. We compared UAV evaluation methods to conventional boots-on-ground methods throughout the Bellamy River Reservoir (Dover, NH, USA) pre-/post-dam removal. We used a UAV-based vegetation classification approach that used a support vector machine algorithm and a featureset composed of SfM-derived elevation and visible vegetation index values to map other, herbaceous, shrub, and tree cover throughout the reservoir (overall accuracies from 83% to 100%), mapping vegetation succession as well as colonization of exposed sediments that occurred post-dam removal. We used SfM-derived topography and the vegetation classifications to map erosion and deposition throughout the reservoir, despite its heavily vegetated condition, and estimate volume changes post-removal. Despite some limitations, such as influences of refraction and vegetation on the SfM topography models, UAV provided information on post-dam removal changes that would have gone unacknowledged by the conventional ecological assessment approaches, demonstrating how UAV technology can provide perspective in restoration evaluation even in less-than-ideal site conditions for SfM. For example, the UAV provided perspective of the magnitude and extent of channel shape changes throughout the reservoir while the boots-on-ground topographic transects were not as reliable for detecting change due to difficulties in navigating the terrain. In addition, UAV provided information on vegetation changes throughout the reservoir that would have been missed by conventional vegetation plots due to their limited spatial coverage. Lastly, the COVID-19 pandemic prevented us from meeting to collect post-dam removal vegetation plot data. UAV enabled data collection that we would have foregone if we relied solely on conventional methods, demonstrating the importance of flexible and adaptive methods for successful restoration monitoring such as those enabled via UAV.

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SHAFROTH, PATRICK B., JONATHAN M. FRIEDMAN, GREGOR T. AUBLE, MICHAEL L. SCOTT i JEFFREY H. BRAATNE. "Potential Responses of Riparian Vegetation to Dam Removal". BioScience 52, nr 8 (2002): 703. http://dx.doi.org/10.1641/0006-3568(2002)052[0703:prorvt]2.0.co;2.

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Carvalho, Fernando Geraldo de, Nelson Silva Pinto, José Max Barbosa de Oliveira Júnior i Leandro Juen. "Effects of marginal vegetation removal on Odonata communities". Acta Limnologica Brasiliensia 25, nr 1 (10.05.2013): 10–18. http://dx.doi.org/10.1590/s2179-975x2013005000013.

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AIM: Here we assess the effects of habitat degradation on individuals of the two suborders of Odonata community of Borecaia river sub-basin. More specifically, we tested the hypothesis that Anisoptera richness would be positively affected by removal of vegetation; on the other hand, Zygoptera richness would be adversely affected by virtue of their ecophysiological requirements; METHODS: We selected 10 streams of similar orders, six preserved and four degraded. Streams characterized as preserved had values of Index of Habitat Integrity (HII) above 0.70 (0.77 ± 0.07, mean ± SD) and continuous forest on both sides with a minimum width of 70 meters. Each site was sampled three times on different days. The effect of vegetation removal on richness was assessed using richness estimated by first order Jackknife; RESULTS: Decreased physical integrity (measured with IIH) of streams had no significant effect on the estimated richness to Odonata in general. However, the estimated richness of Anisoptera showed an inverse relationship with the integrity (r² = 0.485, P = 0.025), i.e., there was a reduction in their species richness with increasing integrity; DISCUSSION: As a general pattern, Anisoptera presents higher richness in an altered site; on the other hand, Zygoptera presents higher richness in a preserved one. This pattern suggests that Odonata needs to be considered at the sub-order level to access the effects of habitat degradation on these insects. Because of its restrictions ecophysiological Odonata varied widely in their composition and species richness between the two types of environments, it reinforces the potential of the order of studies and environmental monitoring also shows that Zygoptera be more affected by changes in habitat. However, further studies including more samples and different streams are need to confirm this pattern, being an interesting line of research for future works.

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Maucieri, Carmelo, Michela Salvato i Maurizio Borin. "Vegetation contribution on phosphorus removal in constructed wetlands". Ecological Engineering 152 (czerwiec 2020): 105853. http://dx.doi.org/10.1016/j.ecoleng.2020.105853.

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Issa, Ziad F., i Nilesh J. Goswami. "Simultaneous lead extraction and vacuum-assisted vegetation removal". HeartRhythm Case Reports 2, nr 1 (styczeń 2016): 17–19. http://dx.doi.org/10.1016/j.hrcr.2015.08.008.

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Yeakley, J. A., J. L. Meyer i W. T. Swank. "Hillslope nutrient flux during near-stream vegetation removal". Water, Air, & Soil Pollution 77, nr 3-4 (październik 1994): 229–46. http://dx.doi.org/10.1007/bf00478421.

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Gong, Yu, Jianghua Wu, Judith Vogt, Thuong Le i Tao Yuan. "Combination of Warming and Vegetation Composition Change Strengthens the Environmental Controls on N2O Fluxes in a Boreal Peatland". Atmosphere 9, nr 12 (6.12.2018): 480. http://dx.doi.org/10.3390/atmos9120480.

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Climate warming and vegetation composition change are expected to influence greenhouse gas emissions from boreal peatlands. However, the interactive effects of warming and different vegetation compositions on N2O dynamics are poorly known, although N2O is a very potent greenhouse gas. In this study, manipulated warming and vegetation composition change were conducted in a boreal peatland to investigate the effects on N2O fluxes during the growing seasons in 2015 and 2016. We did not find a significant effect of warming treatment and combination treatments of warming and vegetation composition change on N2O fluxes. However, sedge removal treatment significantly increased N2O emissions by three-fold. Compared with the treatment of shrub and sedge removal, the combined treatment of warming and shrub and sedge removal significantly increased N2O consumption by five-fold. Similar to N2O fluxes, the cumulative N2O flux increased by ~3.5 times under sedge removal treatment, but this effect was not significant. In addition, the results showed that total soil nitrogen was the main control for N2O fluxes under combinative treatments of warming and sedge/shrub removal, while soil temperature and dissolved organic carbon were the main controls for N2O release under warming combined with the removal of all vascular plants. Our results indicate that boreal peatlands have a negligible effect on N2O fluxes in the short-term under climate change, and environmental controls on N2O fluxes become increasingly important under the condition of warming and vegetation composition change.

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Shibuya, S., K. Kubota i M. Ohsawa. "Effects of small-scale management on biodiversity of an abandoned coppice forest in Japan: a case study on vegetation regeneration and ground beetle community". Web Ecology 8, nr 1 (19.11.2008): 116–24. http://dx.doi.org/10.5194/we-8-116-2008.

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Abstract. We studied the effects of small-scale vegetation disturbances on biodiversity in an abandoned coppice forest in central Japan during 2004–2006. We assessed biodiversity by examining vegetation regeneration and by changes in the diversity and abundance of ground beetles after experimental manipulations including tree felling, vegetation clearing, and litter removal. Our experimental design was dictated by the need of producing only small disturbances; therefore we could not replicate plots. Instead, we used a repeated measures approach during three years to document the consistency of experimental effects. We found that the diversity of regenerating vegetation increased dramatically due to recruitment of many new species after clearing ground vegetation. Tree cutting caused strong environmental changes and affected vegetation regeneration rate but not diversity. Tree cutting also significantly increased the diversity of ground beetle species, while litter removal affected the abundance of ground beetles. Our results suggest that a sound conservation practice shall combine tree cutting with ground vegetation clearing and litter removal. Besides, conservation of abandoned forests may be based on low-intensity labor, including tree cutting on restricted areas. Finally, ground beetles appeared to be surprisingly sensitive to vegetation disturbance on a restricted area and thus can be suggested for monitoring such small-scale-disturbance-based conservation practices.

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Vélez, Sergio, Enrique Barajas, José Antonio Rubio, Rubén Vacas i Carlos Poblete-Echeverría. "Effect of Missing Vines on Total Leaf Area Determined by NDVI Calculated from Sentinel Satellite Data: Progressive Vine Removal Experiments". Applied Sciences 10, nr 10 (23.05.2020): 3612. http://dx.doi.org/10.3390/app10103612.

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Remote Sensing (RS) allows the estimation of some important vineyard parameters. There are several platforms for obtaining RS information. In this context, Sentinel satellites are a valuable tool for RS since they provide free and regular images of the earth’s surface. However, several problems regarding the low-resolution of the imagery arise when using this technology, such as handling mixed pixels that include vegetation, soil and shadows. Under this condition, the Normalized Difference Vegetation Index (NDVI) value in a particular pixel is an indicator of the amount of vegetation (canopy area) rather than the NDVI from the canopy (as a vigour expression), but its reliability varies depending on several factors, such as the presence of mixed pixels or the effect of missing vines (a vineyard, once established, generally loses grapevines each year due to diseases, abiotic stress, etc.). In this study, a vine removal simulation (greenhouse experiment) and an actual vine removal (field experiment) were carried out. In the field experiment, the position of the Sentinel-2 pixels was marked using high-precision GPS. Controlled removal of vines from a block of cv. Cabernet Sauvignon was done in four steps. The removal of the vines was done during the summer of 2019, matching with the start of the maximum vegetative growth. The Total Leaf Area (TLA) of each pixel was calculated using destructive field measurements. The operations were planned to have two satellite images available between each removal step. As a result, a strong linear relationship (R2 = 0.986 and R2 = 0.72) was obtained between the TLA and NDVI reductions, which quantitatively indicates the effect of the missing vines on the NDVI values.

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Viveros, José Antonio Fernández, Georgina Martínez-Reséndiz, Florentina Zurita, José Luis Marín-Muñiz, María Cristina López Méndez, Sergio Zamora i Luis Carlos Sandoval Herazo. "Partially Saturated Vertical Constructed Wetlands and Free-Flow Vertical Constructed Wetlands for Pilot-Scale Municipal/Swine Wastewater Treatment Using Heliconia latispatha". Water 14, nr 23 (27.11.2022): 3860. http://dx.doi.org/10.3390/w14233860.

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Partially saturated vertical constructed wetlands (PSV-CWs) and free-flow vertical constructed wetlands (FFV-CWS) are treatment systems for which there is limited information on their operation in tropical climates and even scarcer information on their use for municipal/swine wastewater treatment. In this work, the removal of pollutants from municipal wastewater mixed with swine effluents was evaluated using PSV-CWs and FFV-CWs, at pilot scale, with the presence and absence of vegetation in a tropical climate. Six vertical flow CWs made up of polyvinyl chloride (1 m high and 0.5 m in diameter) were used; three were operated with free-flow conditions and three with partially saturated conditions. In each type of configuration, two reactors were planted with an individual of Heliconia latispatha, and one remained without vegetation. They were fed with municipal wastewater mixed with 50% of swine wastewater. Their ability to remove COD, TSS, TP, TN, N-NH4, and N-NO3 and plant development were evaluated. Heliconia latispatha registered better results of adaptation and vegetative development in the PSV-CWs in comparison with FFV-CWs measured as total biomass (5697.1 g/m2 and 5095.7 g/m2, respectively). PSV-CWs were slightly better for TSS elimination (4.21%), while FFV-CWs presented a better performance for TN removal (3.76%), N-NH4 (3.94%) and N-NO3 (4.76%) in the systems with vegetation; no significant difference (p ˃ 0.05) was found between the two types of CWs for the removal of COD and TP. However, significant differences (p ˂ 0.05) were found between the systems with vegetation and those without vegetation in both configurations. These results demonstrate that PSV-CWs represent a better option for the treatment of municipal/swine wastewater since their efficiency was slightly higher than, or similar to that of, FFV-CWs and allowed a better development of H. latispatha.

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Hammer, Donald A., i Robert L. Knight. "Designing Constructed Wetlands for Nitrogen Removal". Water Science and Technology 29, nr 4 (1.02.1994): 15–27. http://dx.doi.org/10.2166/wst.1994.0148.

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Many constructed wetlands adequately treat BOD5, TSS, and bacteria. However, a review of nitrogen (N) data from 52 constructed and natural wetlands in the North American data base confirmed that N removal was variable. Nitrification and denitrification require aerobic and anaerobic conditions. This paper presents case histories of systems that use alternating shallow and deep water zones to create both environments. Regression analysis of N removal and N loadings in 18 shallow-deep water systems suggested that NH4+ loading (kg N/ha/day) could be used to predict effluent NH4+ values. Combinations of shallow water-emergent vegetation and deep water-submergent vegetation with low NH4+ (and TKN) loading rates can produce very low levels of discharged NH4+.

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Chiemchaisri, Chart, Wilai Chiemchaisri i Chayanid Witthayapirom. "Remediation of MSW landfill leachate by permeable reactive barrier with vegetation". Water Science and Technology 71, nr 9 (10.03.2015): 1389–97. http://dx.doi.org/10.2166/wst.2015.111.

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This research was conducted to investigate in situ treatment of leachate by pilot-scale permeable reactive barrier (PRB) with vegetation. Two different types of PRB media, with and without the presence of ferric chloride sludge, for the removal of pollutants were examined. The composite media of PRB comprised a clay and sand mixture of 40:60%w/w (system 1) and a clay, ferric chloride sludge and sand mixture of 30:10:60%w/w (system 2). The system was operated at a hydraulic loading rate of 0.028 m3/m2.d and hydraulic retention time of 10 days. The results showed that the performance of system 2 was better in terms of pollutant removal efficiencies, with average biochemical oxygen demand, chemical oxygen demand and total Kjeldahl nitrogen removals of 76.1%, 68.5% and 73.5%, respectively. Fluorescence excitation-emission matrix analyses of water samples and sequential extraction of PRB media suggested the removal of humic substances through the formation of iron–organic complex. Greenhouse gas (GHG) emissions during the treatment of PRB were 8.2–52.1 mgCH4/m2.d, 69.1–601.8 mgCO2/m2.d and 0.04–0.99 mgN2O/m2.d. The use of system 2 with vegetation resulted in lower GHG emissions. The results show that PRB with vegetation could be used as a primary treatment for leachate from closed landfill sites.

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Kaighn, Robert J., i Shaw L. Yu. "Testing of Roadside Vegetation for Highway Runoff Pollutant Removal". Transportation Research Record: Journal of the Transportation Research Board 1523, nr 1 (styczeń 1996): 116–23. http://dx.doi.org/10.1177/0361198196152300114.

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A field monitoring program was begun in 1991 to test the ability of grassed swales to remove pollutants from highway runoff. The two swales monitored had different slopes, traffic volumes, and vegetation heights, all of which can affect pollutant removal. One had a check dam, which proved to significantly influence pollutant removal. Also, the pollutant-removal ability of a short buffer strip was examined. Pollutants monitored included total suspended solids, chemical oxygen demand, total phosphorus, and total zinc. Manual and automatic sampling techniques were used to monitor runoff. The results suggest that properly designed short buffer strips and swales with check dams can remove pollutants from highway runoff.

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Li, Yali, Ana Deletic i David T. McCarthy. "Copper-zeolite integrated stormwater biofilter for nutrient removal – the impact of intermittent wetting and drying conditions". Blue-Green Systems 2, nr 1 (1.01.2020): 352–63. http://dx.doi.org/10.2166/bgs.2020.016.

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Abstract A large-scale column study was conducted to examine the sediment and nutrient removal performance of stormwater biofilters that contained layers of novel copper-zeolite filter media. The filters were exposed to stormwater under varied dosing frequency over 33 weeks and were assessed for their hydraulic performance and their efficiency in removing sediment and nutrients. The non-vegetated sand filters with layers of copper-zeolite media (SCu filters) achieved consistently good removal of total phosphorus (87%) despite the challenging dry-wet cycles, and the effluent concentration met a long-term irrigation guideline (0.05 mg/L). The same design achieved 51% removal of total nitrogen above the Australian runoff quality load reduction targets (45%). Incorporation of Leptospermum continentale into the copper-zeolite filters (LCCu-T) maintained the phosphorus removal (86%) and led to a slight increase in total nitrogen removal (57%). Both designs maintained good water permeability (200 mm/h at the end of the last wet period). Copper-zeolite played a mixed role in the system: enhancing nutrients removal through precipitation and ion exchange, maintaining high water permeability, limiting the advantages of vegetation on nutrient removal. Future studies should refine biofilter design and vegetation selection to augment the performance of copper-zeolite filters by integrating the advantages of vegetation on nutrient removal.

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Pitt, D. G., Andrée E. Morneault, Philip Bunce i F. Wayne Bell. "Five Years of Vegetation Succession Following Vegetation Management Treatments in a Jack Pine Ecosystem". Northern Journal of Applied Forestry 17, nr 3 (1.09.2000): 100–109. http://dx.doi.org/10.1093/njaf/17.3.100.

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Abstract Five years of data on vegetation dynamics and succession are provided for six operational release treatments applied to three 2- to 4-yr-old jack pine (Pinus banksiana Lamb.) plantations in central Ontario. Treatments included 3 yr of annual noncrop vegetation removal, conventional aerial spray with glyphosate (1.42 kg ae/ha), ground application of glyphosate with a mist blower, basal-bark application of triclopyr, motor-manual cutting (brush saw), and no treatment. Conventional aerial spraying and annual removal resulted in the greatest jack pine crop growth, with trees exceeding 90% crown closure, 7 cm in groundline diameter, and 3 m in height (stem volume index = 5.1 dm³) after 5 growing seasons. The cover of herbaceous plants was highest (30–50%) in the aerial spray plots during the observation period. Deciduous tree, shrub, and fern species remained well represented on these plots, although total cover and height were low (≤ 35% and 1 m, respectively). Mist-blower and brush-saw plots contained mid-sized pine (3.5 dm³) with 69% crown closure. In contrast, untreated and basal-bark plots contained the smallest pine (2.3 dm3 and 31% crown closure), likely caused by heavy competition and herbicide damage, respectively. On mist-blower and basal-bark plots, good height growth was observed on untreated deciduous trees; low-shrub and fern cover remained high (46 and 30%, respectively); and herbaceous cover increased gradually to 22%. On brush-saw plots, recovery of woody cover was rapid, but height growth was relatively slow. Deciduous trees and tall shrubs dominated untreated sites (> 70% cover) by the end of the fifth growing season. Successional trends suggest that aerial spray and annual removal treatments will produce pure jack pine stands at maturity; mist blower, basal bark, and brush-saw treatments may produce mixedwood stands; and untreated plots will likely be dominated by hardwoods. North. J. Appl. For. 17(3):100–109.

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Almeida, C., D. Silva, C. G. Messias, L. S. Soler, L. H. Gusmão, L. E. P. Maurano, T. Souza i in. "MAPPING NATURAL NON-FOREST VEGETATION REMOVAL IN THE BRAZILIAN AMAZON – A PILOT PROJECT". International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B3-2022 (31.05.2022): 1341–48. http://dx.doi.org/10.5194/isprs-archives-xliii-b3-2022-1341-2022.

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Abstract. 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.

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Lhotka, John M., i Edward F. Loewenstein. "Effect of Midstory Removal on Understory Light Availability and the 2–Year Response of Underplanted Cherrybark Oak Seedlings". Southern Journal of Applied Forestry 33, nr 4 (1.11.2009): 171–77. http://dx.doi.org/10.1093/sjaf/33.4.171.

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Abstract This study evaluates the effects of four midstory removal intensities on residual stand structure, understory light availability, and the 2-year growth and survival of underplanted cherrybark oak (Quercus pagoda Raf.) seedlings. It also examines whether survival and growth were affected by the removal of competing understory vegetation <1.4 m tall. The study was conducted in western Georgia, in a mature riparian hardwood forest possessing a dense midstory canopy and an understory dominated by highly competitive nonnative and native species. The removal of all midstory trees increased survival and height and basal diameter growth of cherrybark oak after two growing seasons. Understory light availability increased only when at least half of all midstory trees were removed. Although understory vegetation removal increased 2-year height growth of cherrybark oak, the actual growth difference between treatments was only 5 cm. The removal of understory vegetation had no effect on basal diameter growth or survival. Results suggests that a combination of underplanting and complete midstory removal may be a useful treatment for enhancing advance oak reproduction in riparian hardwood stands. This treatment combination may have utility as the initial step in a shelterwood system when advance reproduction is insufficient.

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Tamburini, Elena, Elisa Soana, Mauro Monti, Elisa Anna Fano i Giuseppe Castaldelli. "Introducing Life Cycle Assessment in Costs and Benefits Analysis of Vegetation Management in Drainage Canals of Lowland Agricultural Landscapes". Water 12, nr 8 (8.08.2020): 2236. http://dx.doi.org/10.3390/w12082236.

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Nitrate pollution remains an unsolved issue worldwide, causing serious effects on water quality and eutrophication of freshwater and brackish water environments. Its economic costs are still underestimated. To reduce nitrogen excess, constructed wetlands are usually recognized as a solution but, in recent years, interest has been raised in the role of ditches and canals in nitrogen removal. In this study, we investigated the environmental and economical sustainability of nitrogen removal capacity, using as a model study a lowland agricultural sub-basin of the Po River (Northern Italy), where the role of aquatic vegetation and related microbial processes on the mitigation of nitrate pollution has been extensively studied. Based on the Life Cycle Assessment (LCA) approach and costs and benefits analysis (CBA), the effectiveness of two different scenarios of vegetation management, which differ for the timing of mowing, have been compared concerning the nitrogen removal via denitrification and other terms of environmental sustainability. The results highlighted that postponing the mowing to the end of the vegetative season would contribute to buffering up to 90% of the nitrogen load conveyed by the canal network during the irrigation period and would reduce by an order of magnitude the costs of eutrophication potential.

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Sandoval, Luis, José Luis Marín-Muñíz, Jacel Adame-García, Gregorio Fernández-Lambert i Florentina Zurita. "Effect of Spathiphyllum blandum on the removal of ibuprofen and conventional pollutants from polluted river water, in fully saturated constructed wetlands at mesocosm level". Journal of Water and Health 18, nr 2 (12.03.2020): 224–28. http://dx.doi.org/10.2166/wh.2020.232.

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Abstract In this study, the effect of Spathiphyllum blandum on the removal of ibuprofen (IB) and conventional pollutants such as chemical oxygen demand (COD), total nitrogen (TN), ammonium (NH4+-N), total phosphorus (TP), and total suspended solids (TSS) is reported; this, through its use as an emergent vegetation in fully saturated (FS) constructed wetlands (CWs) at mesocosm level treating polluted river water. With the exception of TP and COD, it was found that for TN (12%), NH4+-N (11%), TSS (19%), and IB (23%), the removals in systems with vegetation were superior to systems without vegetation (p < 0.05). These findings demonstrate the importance of the species S. blandum, in particular, for the removal of ibuprofen, which is an anti-inflammatory drug commonly found in effluents of wastewater treatment plants. Thus, the results obtained provide information that can be used for the design of future efficient large-scale systems using a new ornamental species, mainly under tropical climatic conditions. This article has been made Open Access thanks to the generous support of a global network of libraries as part of the Knowledge Unlatched Select initiative.

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Brandon, Dennis Leroy, Victor Frank Medina i Agnes Belinda Morrow. "A Case History Study of the Recycling Efforts from the United States Army Corps of Engineers Hurricane Katrina Debris Removal Mission in Mississippi". Advances in Civil Engineering 2011 (2011): 1–9. http://dx.doi.org/10.1155/2011/526256.

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In support of the Federal Emergency Management Agency (FEMA), the US Army Corps of Engineers (USACE) managed the removal of Hurricane Katrina storm debris in several states. This paper focuses on the debris removal practices in 16 southern Mississippi counties and the recycling efforts. Debris was removed from public and private property. The debris included vegetation, construction material, electronic waste, vehicles, and vessels. The scope of the USACE mission was expanded several times. The scope within the respective counties varied from vegetation only to the removal of every eligible form of debris. The recommendations proposed should enhance recycling efforts during future debris removal missions.

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McLaughlin, J. F. "Engaging Birds in Vegetation Restoration after Elwha Dam Removal". Ecological Restoration 31, nr 1 (21.01.2013): 46–56. http://dx.doi.org/10.3368/er.31.1.46.

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Winikoff, Sarah G., Daniel J. Larkin, Shana L. Meier i Jacques C. Finlay. "Vegetation trajectories of restored agricultural wetlands following sediment removal". Restoration Ecology 28, nr 3 (27.02.2020): 612–22. http://dx.doi.org/10.1111/rec.13128.

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García-Fayos, Patricio, Esther Bochet i Artemi Cerdà. "Seed removal susceptibility through soil erosion shapes vegetation composition". Plant and Soil 334, nr 1-2 (15.04.2010): 289–97. http://dx.doi.org/10.1007/s11104-010-0382-6.

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Morrison, Janet A. "Wetland vegetation before and after experimental purple loosestrife removal". Wetlands 22, nr 1 (marzec 2002): 159–69. http://dx.doi.org/10.1672/0277-5212(2002)022[0159:wvbaae]2.0.co;2.

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Wang, Ying, i Ki-Young Koo. "Vegetation Removal on 3D Point Cloud Reconstruction of Cut-Slopes Using U-Net". Applied Sciences 12, nr 1 (31.12.2021): 395. http://dx.doi.org/10.3390/app12010395.

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The 3D point cloud reconstruction from photos taken by an unmanned aerial vehicle (UAV) is a promising tool for monitoring and managing risks of cut-slopes. However, surface changes on cut-slopes are likely to be hidden by seasonal vegetation variations on the cut-slopes. This paper proposes a vegetation removal method for 3D reconstructed point clouds using (1) a 2D image segmentation deep learning model and (2) projection matrices available from photogrammetry. For a given point cloud, each 3D point of it is reprojected into the image coordinates by the projection matrices to determine if it belongs to vegetation or not using the 2D image segmentation model. The 3D points belonging to vegetation in the 2D images are deleted from the point cloud. The effort to build a 2D image segmentation model was significantly reduced by using U-Net with the dataset prepared by the colour index method complemented by manual trimming. The proposed method was applied to a cut-slope in Doam Dam in South Korea, and showed that vegetation from the two point clouds of the cut-slope at winter and summer was removed successfully. The M3C2 distance between the two vegetation-removed point clouds showed a feasibility of the proposed method as a tool to reveal actual change of cut-slopes without the effect of vegetation.

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Melečková, Zuzana, Dobromil Galvánek, Daniel Dítě i Pavol Eliáš. "Effect of experimental top soil removal on vegetation of Pannonian salt steppes". Open Life Sciences 8, nr 12 (1.12.2013): 1204–15. http://dx.doi.org/10.2478/s11535-013-0227-4.

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AbstractInland saline habitats of the Pannonian Lowland exhibit a specific variety of grasslands determined by a soil salinity gradient. Changes in the hydrological regime and absence of management have resulted in heavy degradation of the vegetation. The impact of topsoil removal on salt steppes was tested by a 3-year small-scale manipulated experiment in SW Slovakia (Kamenínske Slanisko Nature Reserve). Topsoil was removed in three contrasting types of vegetation with different soil salinities, i.e. in different stages of habitat degradation. Data were analysed by multi-way ANOVA and by multivariate methods. Species richness decreased and the proportion of halophytes increased significantly in the two types with the highest soil salinity; however, the total number of halophytes was not influenced by soil removal. The treatment caused inhibition of secondary succession on the plots with the highest salinity. The effect of the soil removal was only short-term in the vegetation with moderate salinity and on heavily degraded and desalinized types it even stimulated further recruitment of ruderal species. Topsoil removal has only limited potential for the restoration of Pannonian salt steppes. It should be applied only in slightly degraded vegetation, where salt accumulation is still present and target species propagules are available.

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Claeson, Shannon M., i Peter A. Bisson. "Passive Reestablishment of Riparian Vegetation Following Removal of Invasive Knotweed (Polygonum)". Invasive Plant Science and Management 6, nr 2 (czerwiec 2013): 208–18. http://dx.doi.org/10.1614/ipsm-d-12-00070.1.

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AbstractJapanese knotweed and congeners are invasive to North America and Europe and spread aggressively along rivers establishing dense monotypic stands, thereby reducing native riparian plant diversity, structure, and function. Noxious weed control programs attempt to eradicate the knotweed with repeated herbicide applications under the assumption that the system will recover to a native assemblage which will inhibit future invasions. However, eradication efficacy studies typically only measure the amount of knotweed reduced, not the reestablished species diversity or plant origins. For a community scale efficacy study, we measured vascular plant species diversity and cover in riparian areas along five rivers in Washington State, 3 to 6 years after Bohemian knotweed was initially treated with herbicide. Plant species composition was compared between riparian sites treated to remove knotweed and reference sites where knotweed was absent. Sites where knotweed had been removed had significantly more exotic species and vegetative cover than reference sites; however, native species richness and cover were greater in reference sites and areas with more overstory vegetation. The native plants observed were primarily shade tolerant and perennial, as opposed to many of the exotics, which were shade-intolerant annuals. In general, reestablishment of native and exotic vegetation was not related to pretreatment knotweed stem count, size of the invaded area, or timing of herbicide application. However, residual native tree cover was negatively correlated with initial knotweed stem count. Monitoring the success of restoration objectives (e.g., native plant reestablishment or increased species diversity) and characterizing associated habitat features following knotweed eradication will help in the development of site-specific protocols for successful plant community scale restoration.

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Littke, K. M., T. B. Harrington, S. M. Holub, W. R. Littke, R. B. Harrison i E. C. Turnblom. "Douglas-Fir Biomass Allocation and Net Nutrient Pools 15–20 Years after Organic Matter Removal and Vegetation Control". Forests 11, nr 9 (22.09.2020): 1022. http://dx.doi.org/10.3390/f11091022.

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Douglas-fir (Pseudotsuga menziesiivar. menziesii (Mirbel) Franco) plantation forests of the coastal Pacific Northwest have been intensively managed to improve the yield of forest products. However, the long-term effects of these management techniques have received limited research attention in this region. Three affiliate Long-Term Soil Productivity study sites were installed in Douglas-fir forests to understand the impacts of organic matter removals and vegetation control on soil productivity over time. Matlock and Fall River are located in Washington, USA and Molalla is located in Oregon. Organic matter removal treatments included traditional bole-only harvest (BO), whole tree removals (WT), and a whole tree plus coarse woody debris removal (WT+) (Fall River only). Five years of annual vegetation control (AVC) was compared with a conventional initial vegetation control (IVC) treatment at all sites. Douglas-fir biomass allocation to foliage, branch, and stem components was modeled using 15- to 20-year-old trees from this study along with 5- to 47-year-old trees from previous studies on these sites. Across all sites, model predictions indicated that the WT treatment had 7.1 to 9.7 Mg ha−1 less Douglas-fir biomass than the BO treatment. There was 1.5 to 20.5 Mg ha−1 greater Douglas-fir biomass in the AVC treatment than in the IVC treatment at all sites. Douglas-fir carbon and nitrogen biomass were consistently lower in the WT treatment, but there were no significant changes in overall site nutrient pools. The AVC treatment resulted in greater Douglas-fir nutrient pools yet there was a net loss in site calcium, magnesium, and potassium due to lower forest floor and soil base cation pools. While WT removals did not significantly affect site nutrition, the decrease in Douglas-fir biomass at all sites and increase in invasive Scotch broom (Cytisus scoparius (L.) Link) biomass at Matlock suggests that the standard practice of retaining harvest residuals is beneficial. The use of intensive vegetation control to improve Douglas-fir biomass and nutrition must be balanced with retaining soil base cations.

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Dracup, Evan C., Daniel M. Keppie i Graham J. Forbes. "Woodland mouse and vole response to increased structural diversity following midrotation commercial thinning in spruce plantations". Canadian Journal of Forest Research 45, nr 8 (sierpień 2015): 1121–31. http://dx.doi.org/10.1139/cjfr-2014-0472.

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We assessed whether commercially thinning (CT) spruce (Picea spp.) plantations (40% basal area removal) can cause structural changes in fine woody debris (FWD) and understory vegetation to improve habitat quality for small rodents in northwestern New Brunswick, Canada. We created three contrasting environments (FWD rich – understory vegetation rich, FWD poor – understory vegetation rich, and FWD poor – understory vegetation poor) by establishing CT with debris retention (merchantable trunk removal), CT with all debris removed (full tree removal), and non-CT (plantation without CT) in six midrotation white spruce (Picea glauca (Moench) Voss) plantations. We live-trapped small mammals in each plantation during spring and summer of 2011 and 2012 and estimated animal density and survival with capture–recapture models. Southern red-backed vole (Myodes gapperi (Vigors, 1830)) density was two to three times greater in CT with debris retention than in either non-CT or CT with debris removal, and their survival rate was twice that in CT with debris removal. Woodland jumping mouse (Napaeozapus insignis (Miller, 1891)) density was two to five times greater in non-CT than in either CT treatment. Deer mice (Peromyscus maniculatus (Wagner, 1845)) did not show any treatment effect. Productivity and demographics were not affected by CT treatment for any species. We found evidence that midrotation spruce plantations are used differently by small mammal species based on stand condition and recommend that managers maintain plantations in CT and non-CT states.

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Page, M., RJS Beeton i JJ Mott. "Grass response to shrub removal in two semi-arid vegetation communities." Rangeland Journal 22, nr 2 (2000): 220. http://dx.doi.org/10.1071/rj0000220.

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The control of woody weeds in the mulga lands of south-west Queensland is commonly regarded as essential for restoration of degraded systems. However, these shrubs have become a dominant and stable component of many mulga land ecosystems, and their removal may have unknown ecosystem impacts. This paper reports an experiment to determine the effect of woody weeds and grazing pressure on grass recruitment, cover and diversity in two vegetation communities in Queensland's mulga lands. Both factors influence grass recruitment, cover and diversity, but the response differs between the two vegetation communities investigated. The overall grass cover is consistently greater in sites where woody weeds were removed, and where grazing pressure was lowest. However, in the Dunefields community the cover and frequency of grass plants responded more to the removal of woody weeds than in the Mulga Sandplain community. In contrast, in the Mulga Sandplain community the grasses responded more to reducing or removing grazing pressure. Results suggest that subtle differences between systems influence grass dynamics, highlighting the need for community-specific research and management. Key words: shrub removal, semi-arid vegetation, vegetation communities, woody weeds

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Richardson, Brian. "Vegetation management practices in plantation forests of Australia and New Zealand". Canadian Journal of Forest Research 23, nr 10 (1.10.1993): 1989–2005. http://dx.doi.org/10.1139/x93-250.

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Radiata pine (Pinusradiata D. Don) is the predominant species in plantation forests of Australia and New Zealand. Removal or suppression of noncrop vegetation is often carried out to enhance crop growth and survival by reducing competition for water, light, and nutrients. Other reasons for vegetation removal include microclimate modification, providing access into stands, and fire hazard reduction. Many studies have demonstrated large increases in crop growth from removing noncrop vegetation. Vegetation management can also mean introducing noncrop species to improve site quality, to suppress unwanted species, or to provide fodder for grazing. While herbicides are still the most widely used weed control tool, nonchemical methods are of increasing importance. The role of machinery is likely to increase in both countries as the use of fire for vegetation management and general site preparation declines. To calculate the long-term cost–benefit of vegetation management, a better understanding of the crop growth response to these treatments is essential. This requires experiments that focus on the role of both crop and noncrop species in hydrological and nutrient cycles. Personal computer based decision support systems are likely to play an increasing role as an aid to cost-effective vegetation management decision making.

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Elkamhawy, Aya, i Choon-Man Jang. "Performance Evaluation of Hybrid Air Purification System with Vegetation Soil and Electrostatic Precipitator Filters". Sustainability 12, nr 13 (6.07.2020): 5428. http://dx.doi.org/10.3390/su12135428.

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This paper describes designing, manufacturing, and evaluating an eco-friendly modular-type air purification system to enhance the removal efficiency of fine particulate matter (PM) in urban public spaces, especially in hotspots. This system consists of artificial soil based-vegetation and electrostatic precipitator (ESP) filters. Unlike the so-called passive removal method, which adsorbs fine PM only by the leaves of plants, the vegetation soil filter based on multi-layered different artificial soils adopts an active removal method in which air purification is performed in the soil itself, bypassing external air by using the air circulation fan in the soil. The ESP filter is designed and evaluated to have a high fine PM removal efficiency, even at high suction velocity, to remove large amounts of outdoor fine PM. Throughout the experimental measurements on the hybrid air purification system with vegetation soil and ESP filters, it is observed that the vegetation soil filter has a 78.5% reduction efficiency for PM2.5 and a 47% for PM10 at the inlet air velocity of 0.15 m/s. The ESP filter also has a 73.1% reduction efficiency for PM2.5 and 87.3% for PM10 at an inlet air velocity of 3 m/s. Based on the performance evaluations of the vegetation soil filter and the ESP filter, it is noted that each individual module will be applied to an air purification tower with vertical expansion and installed in a high concentration area of fine PM in a downtown area to contribute to the fine PM reduction in the community.

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Yuan, Jia-jia, Wen-yi Dong, Fei-yun Sun, Ke Zhao i Pu Li. "Enhanced heavy metal removal by wetland vegetations and its significance for vegetation-activated sludge process configuration". Desalination and Water Treatment 57, nr 52 (19.02.2016): 25153–60. http://dx.doi.org/10.1080/19443994.2016.1150885.

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McNabb, David H., Kathryn Baker-Katz i Steven D. Tesch. "Machine Site Preparation Improves Seedling Performance on a High-Elevation Site in Southwest Oregon". Western Journal of Applied Forestry 8, nr 3 (1.07.1993): 95–98. http://dx.doi.org/10.1093/wjaf/8.3.95.

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Abstract Douglas-fir (Pseudotsuga menziesii) seedlings planted on areas receiving one of four site-preparation treatments (scarify, scarify/till, soil removal and soil removal/till) and on unprepared control areas were compared for 5 yr at a high-elevation, nutrient-poor site in the western Siskiyou Mountains of southwest Oregon. Fifth-year survival of seedlings was at least 85% among machine-prepared plots, compared to 42% on control plots. Cover of competing vegetation remained less than 25% during the period for all machine treatments. In contrast, vegetation cover on control plots was 30% at the time of planting and increased to nearly 75% after 5 yr. Competing vegetation clearly impeded seedling performance. The effects of unusually droughty conditions at the time of planting in 1982 were examined further by interplanting additional seedlings in the soil-removal treatment in 1985. The interplanting was followed by more normal spring precipitation, and seedlings grew better over 5 yr than those planted in 1982. The slow recovery of competing vegetation and generally poor seedling growth on all treatments during both planting years are attributed to low soil fertility. West. J. Appl. For. 8(3):95-98.

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Kemp, Jeanette E., i Alexander S. Kutt. "Vegetation change 10 years after cattle removal in a savanna landscape". Rangeland Journal 42, nr 2 (2020): 73. http://dx.doi.org/10.1071/rj19092.

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Following the establishment of a conservation reserve, changes in ground stratum vegetation following removal of cattle were examined in a northern Australian savanna over a 10-year period. The floristic composition of 40 vegetation plots in lowland savannas were surveyed shortly after acquisition of the property, and then surveyed twice in the following 10 years after cattle removal. Some notable ecosystem-transforming introduced species (weeds) such as Themeda quadrivalvis remained relatively stable, whereas the pasture legume Stylosanthes scabra increased in cover. The species richness of both native and introduced plants increased. Various plant functional groups changed in relative cover, with a decline in relatively unpalatable grasses and a corresponding increase in palatable grasses, responses that are consistent with recovery from grazing pressure. Our results show that removal of cattle in highly disturbed savanna ecosystems can have both positive and negative results for native ground stratum vegetation in the first decade of recovery.

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DeBusk, T. A., M. Kharbanda, S. D. Jackson, K. A. Grace, K. Hileman i F. E. Dierberg. "Water, vegetation and sediment gradients in submerged aquatic vegetation mesocosms used for low-level phosphorus removal". Science of The Total Environment 409, nr 23 (listopad 2011): 5046–56. http://dx.doi.org/10.1016/j.scitotenv.2011.08.038.

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Yildiz, O., K. Cromack, S. R. Radosevich, M. A. Martinez-Ghersa i J. E. Baham. "Comparison of 5th- and 14th-year Douglas-fir and understory vegetation responses to selective vegetation removal". Forest Ecology and Management 262, nr 4 (sierpień 2011): 586–97. http://dx.doi.org/10.1016/j.foreco.2011.04.015.

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Peter, David H., i Constance Harrington. "Six years of plant community development after clearcut harvesting in western Washington". Canadian Journal of Forest Research 39, nr 2 (luty 2009): 308–19. http://dx.doi.org/10.1139/x08-170.

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What roles do ruderals and residuals play in early forest succession and how does repeated disturbance affect them? We examined this question by monitoring plant cover and composition on a productive site for 6 years after clearcutting and planting Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco). The replicated experiment included three treatments: vegetation control with five annual herbicide applications superimposed over two levels of slash removal (bole only or total tree plus most other wood) and an untreated control. Three species groups were analyzed: native forest, native ruderals, and exotic ruderals. Without vegetation control, the understory was rapidly invaded by exotic ruderals but was codominated by native and exotic ruderals by year 6. Douglas-fir cover surpassed covers in the three species group covers at least 3 years sooner with herbicide treatments than without. Species richness and coverage were lower for all species groups with vegetation control than without vegetation control. The effects of organic matter removal were much less than that of vegetation control. As predicted by the Intermediate Disturbance Hypothesis, repeated vegetation control resulted in declining cover and richness; however, native forest species were surprisingly resilient, maintaining as much or more cover and richness as the ruderal groups.

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Wu, Yun, Xu-Yu Duan, Guang-Li Liu, Yong Xiang, Bo Shu i Qing-Jun Li. "Vegetation context modifies selection on flowering start and plant height in an orchid perennial herb". Journal of Plant Ecology 14, nr 5 (20.05.2021): 934–44. http://dx.doi.org/10.1093/jpe/rtab048.

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Abstract Aims Identifying the potential role of vegetation context (defined as the density, species identity/diversity and height of co-occurring plants) in modifying selection on floral traits is a critical step for clarifying and predicting the floral evolutionary trajectory in complex co-flowering species competition environments. It is also helpful to understand the variation in pollinator-mediated selection. Methods We experimentally reduced vegetation height around individual plants of Spiranthes sinensis (a bumblebee-pollinated perennial orchid herb) and estimated how vegetation context modified selection on four floral traits (flowering start, plant height, corolla size and number of flowers) through female function and pollen removal over two continuous years. We randomly selected independent plants in each year. Important Findings We demonstrated that vegetation context modified selection for earlier flowering start and shorter plant height of S. sinensis. The strength of selection differed between years. In addition, selection was stronger through female function than through pollen removal. Our findings indicate the potential role of vegetation context in shaping the differentiation and diversification of flowers in angiosperms.

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Junakova, N., i J. Junak. "Use of vegetation for the removal of pollutants from wastewater as an alternative environmental technique for wastewater treatment". IOP Conference Series: Earth and Environmental Science 900, nr 1 (1.11.2021): 012015. http://dx.doi.org/10.1088/1755-1315/900/1/012015.

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Abstract The paper focuses on the evaluation of the use of vegetation for the removal of contaminants from wastewater through vegetation-based wastewater treatment plants. Subsequently, the specific efficiencies of wastewater treatment using a selected vegetation-based wastewater treatment plant are evaluated. The results show that vegetation-based wastewater treatment plants generally work at relatively high treatment efficiency, but one of the main factors influencing the treatment efficiency is the values of pollution indicators at the inflow to the wastewater treatment plant.

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Lautenbach, Joseph M., Nathan Stricker, Michael Ervin, Andy Hershner, Ryan Harris i Chris Smith. "Woody Vegetation Removal Benefits Grassland Birds on Reclaimed Surface Mines". Journal of Fish and Wildlife Management 11, nr 1 (17.12.2019): 89–98. http://dx.doi.org/10.3996/062019-jfwm-053.

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Abstract Grassland birds have declined throughout North America. In the midwestern United States, reclaimed surface mines often provide expanses of contiguous grassland that support grassland birds. However, some reclaimed surface mines often experience severe woody vegetation encroachment, typically by invasive trees and shrubs, including black locust Robinia pseudoacacia, autumn olive Elaeagnus umbellata, and bush honeysuckle Lonicera spp. We conducted point-count surveys to investigate the effects of woody canopy cover and response to treatments of woody vegetation on the abundance of birds. Our treatments were a control, an herbicide application, and an herbicide application followed by cutting and shredding of standing dead woody vegetation. Estimated density of eastern meadowlark Sturnella magna, grasshopper sparrow Ammodramus savannarum, and Henslow's sparrow Centronyx henslowii was 670%, 958%, and 200%, respectively, greater on areas treated with herbicide and shredding and 279%, 666%, and 155%, respectively, greater on areas treated with herbicide-only when compared with control sites. When woody canopy cover increased from 0% to 20%, densities of eastern meadowlark, grasshopper sparrow, and Henslow's sparrow decreased by 83.9%, 74.9%, and 50.7%, respectively. Conversely, densities of eastern towhee Pipilo erythrophthalmus, prairie warbler Setophaga discolor, yellow-breasted chat Icteria virens, and yellow warbler Setophaga petechia increased 67.4%, 57.0%, 34.6%, and 117.7%, respectively, as estimated woody canopy coverage increased from 20% to 60%. Our results showed treating encroaching woody vegetation on reclaimed surface mines with herbicide and shredding increases available habitat used by grassland birds. Maintaining grasslands on reclaimed surface mines at ≤10% woody canopy coverage would be most beneficial to eastern meadowlarks, grasshopper sparrows, and Henslow's sparrows.

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Dudley, Maura P., Kelsey Solomon, Seth Wenger, C. Rhett Jackson, Mary Freeman, Katherine J. Elliott, Chelcy F. Miniat i Catherine M. Pringle. "Do crayfish affect stream ecosystem response to riparian vegetation removal?" Freshwater Biology 66, nr 7 (25.05.2021): 1423–35. http://dx.doi.org/10.1111/fwb.13728.

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TIEDEMANN, ARTHUR R., i JAMES O. KLEMMEDSON. "Responses of desert grassland vegetation to mesquite removal and regrowth". Rangeland Ecology & Management 57, nr 5 (2004): 455. http://dx.doi.org/10.2111/1551-5028(2004)057\[0455:rodgvt\]2.0.co;2.

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Tiedemann, Arthur R., i James O. Klemmedson. "Responses of Desert Grassland Vegetation to Mesquite Removal and Regrowth". Journal of Range Management 57, nr 5 (wrzesień 2004): 455. http://dx.doi.org/10.2307/4003974.

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Smith, W. H. T. "Percutaneous removal of embolised vegetation from left main coronary artery". Heart 92, nr 1 (1.01.2006): 84. http://dx.doi.org/10.1136/hrt.2005.064642.

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