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Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1490
Author(s):  
Justyna Czaja ◽  
Zbigniew Wilczek ◽  
Damian Chmura

As a result of forest fragmentation, ecotones have become an important contribution to the landscape. The areas that include ecotones are constantly growing, thus creating new habitats for plants and animals. The factor that has the greatest impact on the configuration and extent of an ecotone is called the “edge effect”. The aim of this study was to determine the width of the ecotones in forests that are adjacent to an expressway and to characterize the edge effect they produced. The research was performed along ten transects situated at the edge of a forest and in the interior part of a forest (plots from 0 to 200 m). The structures of the forest stand, trees, shrubs, dwarf shrubs and herbs were determined and data on the species composition and species cover were also collected. Results of the statistical analyses (linear mixed models as well as detrended and canonical correspondence analyses) indicated significant changes in the structure, species composition, and species turnover that were dependent on the distance from the edge of the forest. It was shown that shrubs (cover, density, species richness) were the most affected while vascular plants were the least affected. However, the changes were ambiguous. There was either an increase or decrease in the individual parameters of the forest structure and the coverage of forest species. The extent of the forest edge began at a minimum distance of 0–20 m.


ChemPhysChem ◽  
2021 ◽  
Vol 22 (19) ◽  
pp. 1935-1935
Author(s):  
Kailai Lin ◽  
Patrick TomHon ◽  
Sören Lehmkuhl ◽  
Raul Laasner ◽  
Thomas Theis ◽  
...  

2021 ◽  
Vol 17 (2) ◽  
pp. 98-106
Author(s):  
Kobiv Y.Y.

Individual (height of flowering shoot, length of rhizome segments and their number on a growth axis) and group parameters (cover, density of immature individuals, flowering and vegetative shoots) of a clonal tall-herb species Rumex alpinus were studied in the populations undergoing different stages of anthropogenic succession in the Carpathians. The species can form dense Rumiceta alpini ruderal communities on the manured soil near the livestock camps. Rumex alpinus has a long life span and thick long-living rhizomes in which the segments’ size reflects the viability of the individual in previous years. The studied parameters characterize the extent of disturbance in grassland ecosystems on different stages of their anthropogenic or restoration succession. A significant number of immature individuals of seed origin proves the young age of a population and indicates the degrading vector of changes in ecosystems. However, the individuals of seed origin (particularly, immature) are almost or completely missing in the established dense Rumiceta alpini because clonal reproduction prevails there. The highest individual and group parameters of R. alpinus have been registered in the sites that are manured. Cessation of anthropogenic impact results in thinning out of populations and their gradual decline. Annual increments of rhizomes demonstrate a successive increase in the invasive populations and decrease in the regressive ones. R. alpinus is also a component of some native undisturbed communities where it shows moderate viability of individuals and low population density. Thus, high values of individual and group parameters of this species indicate significant disturbance of the area and its low conservation value, while its infrequent occurrence only in some solitary small sites can reflect an absence or low level of devastation of a mountain grassland ecosystem. Keywords: anthropogenic impact, succession, rhizome segments, mountain meadows,Rumicetum alpini Вивчено індивідуальні (висоту генеративного пагона, довжину сегментів кореневища та їхню кількість на осі наростання) і групові параметри (проєктивне покриття,щільність імматурних особин, генеративних і вегетативних пагонів) клонального високотравного виду – Rumex alpinus у популяціях, що перебувають на різних стадіях антропогенної сукцесії в Карпатах. Цей вид здатний утворювати зімкнені рудеральні угруповання – щавельники (Rumiceta alpini) на угноєному ґрунті біля стійбищ худоби. Видові властивий тривалий онтогенез і наявність довговічних масивних кореневищ, у яких розмір сегментів відображає життєвість особини у минулі роки. Досліджені показники характеризують ступінь антропогенних змін у лучних екосистемах Карпат на різних етапах їх дигресивно-демутаційних перетворень. Значна кількість імматурних особин насіннєвого походження свідчить про молодий вік популяції і служить індикатором дигресивного спрямування змін в екосистемі. Натомість, у сформованих щільних щавельниках особини насіннєвого походження (зокрема імматурні) майже або цілком відсутні, оскільки у самовідновленні переважає вегетативне розмноження. Найвищі індивідуальні і групові параметри R. alpinus відзначено на площах, що зазнають підживлення гноївкою. Припинення господарського впливу призводить до розрідження популяцій та їх поступового згасання. В інвазійних популяціях відзначено послідовне збільшення річних приростів кореневищ, натомість у регресивних – їхнє скорочення. Rumex alpinus є також компонентом деяких корінних непорушених угруповань, де виявляє невисоку життєвість особин і низьку щільність популяцій. Отже, високі значення індивідуальних і групових показників цього виду є індикатором значного порушення території та її низької цінності з природоохоронної точки зору, натомість його нечасте трапляння лише на окремих невеликих ділянках може свідчити про відсутність або незначний ступінь девастації гірської лучної екосистеми. Ключові слова: антропогенний вплив, сукцесія, сегменти кореневища, гірські луки, Rumicetum alpini


A new transformation for enhancing utility and efficiency of forestry ecosystem and reduction of stress due to resting sole reliance on arable ecosystem for livelihood was devised. This endeavor reached to a new transformation from forestry to Forestry- Horticulture so as to enable acquiring fruits and nuts, highly effectively useful in bringing feel good and wellness, foster of good health and wealth for nations, under changing climate. Reviw and connaissance survey of suitable horticultural trees which bear fruits and nuts and not get damaged by birds, monkeys and ground moving wild animals were searched coveing India from it boundary in North to South and from West to East. There occurred plentiful fruits and nut trees, bushes and herbs, which will easily grow at sites in forest where no trees existed. The statistics of forestry revealed that mere 2.7 percent of geographical area occuring under forest (21.338%), is dense forest having vegetation cover density of 70% or more and remaing areas under forest have moderate to low vegetation covearage. This new transformation will quickly enhance forest cover, induce carbon sequestration, produce woods of different qualities and additionally produce fruits, nuts, gums and resins and many useful produces such as leaves, herbs, honey etc. These products will be available locally as all states have their own forests and produce commodities for business and trades with huge employment generations in process from production to consumption. This new bio based transformation is implementable, without creating any disparity or grudge and bringing a plausible livelihood from stressful situation occurring due to global warming and climate change.


Author(s):  
Harshita Shetty ◽  
IGS Yasaswi ◽  
Vandana S

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 977
Author(s):  
Meshal M. Abdullah ◽  
Zahraa M. Al-Ali ◽  
Mansour T. Abdullah ◽  
Bader Al-Anzi

The rapid assessment and monitoring of native desert plants are essential in restoration and revegetation projects to track the changes in vegetation patterns in terms of vegetation coverage and structure. This work investigated advanced vegetation monitoring methods utilizing UAVs and remote sensing techniques at the Al Abdali protected site in Kuwait. The study examined the effectiveness of using UAV techniques to assess the structure of desert plants. We specifically examined the use of very-high-resolution aerial imagery to estimate the vegetation structure of Rhanterium epapposum (perennial desert shrub), assess the vegetation cover density changes in desert plants after rainfall events, and investigate the relationship between the distribution of perennial shrub structure and vegetation cover density of annual plants. The images were classified using supervised classification techniques (the SVM method) to assess the changes in desert plants after extreme rainfall events. A digital terrain model (DTM) and a digital surface model (DSM) were also generated to estimate the maximum shrub heights. The classified imagery results show that a significant increase in vegetation coverage occurred in the annual plants after rainfall events. The results also show a reasonable correlation between the shrub heights estimated using UAVs and the ground-truth measurements (R² = 0.66, p < 0.01). The shrub heights were higher in the high-cover-density plots, with coverage >30% and an average height of 77 cm. However, in the medium-cover-density (MD) plots, the coverage was <30%, and the average height was 52 cm. Our study suggests that utilizing UAVs can provide several advantages to critically support future ecological studies and revegetation and restoration programs in desert ecosystems.


Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 307
Author(s):  
Teresa Batista ◽  
José Manuel de Mascarenhas ◽  
Paula Mendes ◽  
Carlos Pinto-Gomes

Vegetation natural heritage can be valued in itself, but also as a habitat for many wildlife species. This study presents a methodological essay concerning the evaluation of plant heritage, applied in Central Alentejo, in the south of Portugal. This evaluation was based on the following criteria: horizontal and vertical structure of vegetation, tree cover density, rare plant species richness, phytocenotic maturity, importance as ecological corridor, historical record, scientific and educational potential and recreational potential. The vegetation heritage value (VHV) was calculated using a linear combination of the weighted criteria. In this way it was possible to identify the most interesting areas for conservation purposes. Of the 7500 km2 analyzed, 52% are natural and semi-natural areas, and of these, 18.8% have very high VHV, 70.7% have high VHV and only 10.5% average VHV. The highest VHV areas are actually included under the protected areas of Natura 2000 sites.


2021 ◽  
Author(s):  
Sara Simona Cipolla ◽  
Nicola Montaldo

&lt;p&gt;&lt;span&gt;In water-limited ecosystems such as those encountered on Mediterranean mountainous areas of shallow soil, climate-induced changes in precipitation regime are expected to influence the ability of remnants of native forests to resist or adapt to predicted reduced precipitation scenarios. The objective of this work was to understand the role of precipitation and physiographic ecosystem properties in woody cover spatial variability of Mediterranean sclerophyllous forests located within main protected areas of the Sardinia Island (Italy), an excellent reference condition for Mediterranean hydrologic studies due to the relatively low urbanization and human activities. Analyzed forests differ in altitude (0-1500 slm.), mean annual precipitation (450-1200 mm) over 95 years of daily data, exposition, dominant species, density, and soil thickness.&lt;/span&gt; &lt;span&gt;Forests have been broken down into 30 * 30 m plots based on their type. Using data from the Landsat satellite sensors, temporal trends in the NDVI (Normalized Difference Vegetation Index) were quantified. We related these trends with different environmental variables to understand the effects of the variation of precipitation regimes and forest type on woody cover density. A significant direct effect of drought has been observed in the dry 2017 in all forests resulting in a significantly reduced NDVI values especially on south facing slopes plots and low soil thickness plots. On the contrary forest canopy were more stable on mesic habitats demonstrating that the availability of soil humidity is more important than solar radiation. Finally, the lowest values of NDVI were observed in semi-arid sclerophyllous forest dominated by species tolerant to drought and very thin stony soil layers. The identification of the factors that contribute the most to the increase in the vulnerability and the decrease of tree cover density of forests will allow to optimize planning and management strategies also under further drier climate changes prospective.&lt;/span&gt;&lt;/p&gt;


2021 ◽  
Vol 66 (1) ◽  
pp. 147-156
Author(s):  
Tuan Pham Anh

The paper presents the results of landscape assessment serving the spatial orientation of ecotourism development in Van Ho district, Son La province. The input data includes: Terrain (elevation, slope, slope direction, ground roughness); Natural (temperature, rainfall, geology and soil); Environment (vegetation cover density, land use activity, protected\ protected area, distance from water source); Socio-economic (distance from residential points, distance from major roads, distance from cultural sites, distance from negative points). The weights of the criteria are determined through AHP method. The component values of the indicators and the overall landscape value were determined by overlaying the maps. The results show that: About 75% of the district area is not suitable for ecotourism development, about 25% of the area is suitable for ecotourism development, distributed in the east and southeast of the district.


2021 ◽  
Vol 13 (3) ◽  
pp. 337 ◽  
Author(s):  
Alena Dostálová ◽  
Mait Lang ◽  
Janis Ivanovs ◽  
Lars T. Waser ◽  
Wolfgang Wagner

The constellation of two Sentinel-1 satellites provides an unprecedented coverage of Synthetic Aperture Radar (SAR) data at high spatial (20 m) and temporal (2 to 6 days over Europe) resolution. The availability of dense time series enables the analysis of the SAR temporal signatures and exploitation of these signatures for classification purposes. Frequent backscatter observations allow derivation of temporally filtered time series that reinforce the effect of changes in vegetation phenology by limiting the influence of short-term changes related to environmental conditions. Recent studies have already shown the potential of multitemporal Sentinel-1 data for forest mapping, forest type classification (coniferous or broadleaved forest) as well as for derivation of phenological variables at local to national scales. In the present study, we tested the viability of a recently published multi-temporal SAR classification method for continental scale forest mapping by applying it over Europe and evaluating the derived forest type and tree cover density maps against the European-wide Copernicus High Resolution Layers (HRL) forest datasets and national-scale forest maps from twelve countries. The comparison with the Copernicus HRL datasets revealed high correspondence over the majority of the European continent with overall accuracies of 86.1% and 73.2% for the forest/non-forest and forest type maps, respectively, and a Pearson correlation coefficient of 0.83 for tree cover density map. Moreover, the evaluation of both datasets against the national forest maps showed that the obtained accuracies of Sentinel-1 forest maps are almost within range of the HRL datasets. The Sentinel-1 forest/non-forest and forest type maps obtained average overall accuracies of 88.2% and 82.7%, respectively, as compared to 90.0% and 87.2% obtained by the Copernicus HRL datasets. This result is especially promising due to the facts that these maps can be produced with a high degree of automation and that only a single year of Sentinel-1 data is required as opposed to the Copernicus HRL forest datasets that are updated every three years.


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