Evaluating the effect of stand properties and site conditions on the forest reflectance from Sentinel-2 time series

Grabska, Ewa; Socha, Jarosław

doi:10.1371/journal.pone.0248459

Cited by 17 publications

(5 citation statements)

References 86 publications

(112 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reasons for changes in the abundance of forest herbs and shrubs during increase in tree-crown density are complex. The general structural characteristics of the entire tree stand are critical for restoration of undergrowth (Grabska & Socha, 2021). Increase in crown density first of all alters the conditions of photosynthesis, reducing the amount of light which reaches the soil, and in the conditions of deciduous forests the sunlight is even impoverished in photosynthetically active radiation (PAR) -rays of the red part of the spectrum, since it had been "filtrated" by the leaves of tree crowns.…”

Section: Resultsmentioning

confidence: 99%

“…They are a unique unification of various live organisms (Omodior et al, 2021;Reese et al, 2022) and physical factors that interact inside the biosphere (Thyroff et al, 2019;Saulino et al, 2022). An important aspect of forest ecosystems is interaction between various levels of the herbaceous cover (Grabska & Socha, 2021) such as trees, shrubs, and herbaceous plants. Crown density of trees, their size and structure, play a fundamental role in the formation and functioning of the herb-shrub stratum of forest ecosystems.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Influence of tree-crown density on dominant plant species of the herb-shrub stratum in the zone of mixed forests

Kovalenko,

Kyrylchuk,

Klymenko

et al. 2023

Biosys. divers.

View full text Add to dashboard Cite

Forest ecosystems are among the most complex and dynamic biological systems of our planet. They play an important role in sustaining biodiversity, regulating the climate, and preserving water resources. Furthermore, they serve as natural filters, improving the quality of soil and air, and also preventing erosive processes. Forests create unique conditions for life of various species of plants and animals, which contributes to maintenance of the natural biodiversity and supports the stability of the ecosystem. Likewise, forests are important for the carbon cycle. They absorb a large amount of carbon, thus hindering global warming. Therefore, forest ecosystems are of paramount ecological value and their preservation is crucial for a balanced functioning of the planet. Our studies were carried out in the forest ecosystems of the Desna-Starohutskyi National Park, which is in the Ukrainian Polissia. The materials and methods of the study included systematic collection of the data on density of tree crowns, and also records of diversity of plants of the herb-shrub stratum in the chosen forest areas. Those data were analyzed using statistical methods. The study results revealed that the crown density has a significant effect on diversity of herb-shrub plants in the lower forest strata. Increase in crown density correlated with decrease in the light availability in the herb-shrub stratum. Change in the crown density towards increase significantly altered the conditions for competition between herbaceous and shrub species. Decrease in light availability led to shift in the competition ratio between the species, promoting dominance of more shade-loving species. Increase in crown density, which often reached 100%, made the competition more severe, especially for key resources (light, water, and nutrients). Because of this, species diversity in the herb-shrub stratum of the forest ecosystems was observed to decrease, and less adapted species were extruded. In general, change in tree-crown density in the forest ecosystem had a significant effect on the dynamics of herbaceous and shrub species, changing competitive relations and the structure of those plant communities. The results we obtained expand the knowledge about interactions between crown density and the structure of herb-shrub stratum, which gives perspectives for more efficient management of forest resources, and can also improve scientific identification and implementation of measures for protection of forest ecosystems.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Influence of tree-crown density on dominant plant species of the herb-shrub stratum in the zone of mixed forests

Kovalenko,

Kyrylchuk,

Klymenko

et al. 2023

Biosys. divers.

View full text Add to dashboard Cite

show abstract

“…This leads to changes in the tree's reflectance across the different parts of the wavelength. Furthermore, the reflectance might also be influenced by understory vegetation [106] because the understory vegetation might present a different spectral response than the canopy leaves [107]. Therefore, it is essential to identify the month the classifier achieves its highest performance.…”

Section: Discussionmentioning

confidence: 99%

Forest Habitat Mapping in Natura2000 Regions in Cyprus Using Sentinel-1, Sentinel-2 and Topographical Features

Prodromou,

Theocharidis,

Gitas

et al. 2024

Remote Sensing

View full text Add to dashboard Cite

Accurate mapping of forest habitats, especially in NATURA sites, is essential information for forest monitoring and sustainable management but also for habitat characterisation and ecosystem functioning. Remote sensing data and spatial modelling allow accurate mapping of the presence and distribution of tree species and habitats and are valuable tools for the long-term assessment of habitat status required by the European Commission. In order to serve the above, the present study aims to propose a methodology to accurately map the spatial distribution of forest habitats in three NATURA2000 sites of Cyprus by employing Sentinel-1 and Sentinel-2 data as well as topographic features using the Google Earth Engine (GEE). A pivotal aspect of the methodology identified was that the best band combination of the Random Forest (RF) classifier achieves the highest performance for mapping the dominant habitats in the three case studies. Specifically, in the Akamas region, eight habitat types have been mapped, in Paphos nine and six in Troodos. These habitat types are included in three of the nine habitat groups based on the EU’s Habitat Directive: the sclerophyllous scrub, rocky habitats and caves and forests. The results show that using the RF algorithm achieves the highest performance, especially using Dataset 6, which is based on S2 bands, spectral indices and topographical features, and Dataset 13, which includes S2, S1, spectral indices and topographical features. These datasets achieve an overall accuracy (OA) of approximately 91–94%. In contrast, Dataset 7, which includes only S1 bands and Dataset 9, which combines S1 bands and spectral indices, achieve the lowest performance with an OA of approximately 25–43%.

show abstract

“…This is because some of the seedlings may have been planted while others-in Finland, often birches and other deciduous trees-are naturally regenerated within the same stand. This allows for a higher impact of reflectance from understory vegetation [4][5][6]. The seedlings may also be Remote Sens.…”

Section: Introductionmentioning

confidence: 99%

A New Approach for Feeding Multispectral Imagery into Convolutional Neural Networks Improved Classification of Seedlings

Imangholiloo,

Luoma,

Holopainen

et al. 2023

Remote Sensing

View full text Add to dashboard Cite

Tree species information is important for forest management, especially in seedling stands. To mitigate the spectral admixture of understory reflectance with small and lesser foliaged seedling canopies, we proposed an image pre-processing step based on the canopy threshold (Cth) applied on drone-based multispectral images prior to feeding classifiers. This study focused on (1) improving the classification of seedlings by applying the introduced technique; (2) comparing the classification accuracies of the convolutional neural network (CNN) and random forest (RF) methods; and (3) improving classification accuracy by fusing vegetation indices to multispectral data. A classification of 5417 field-located seedlings from 75 sample plots showed that applying the Cth technique improved the overall accuracy (OA) of species classification from 75.7% to 78.5% on the Cth-affected subset of the test dataset in CNN method (1). The OA was more accurate in CNN (79.9%) compared to RF (68.3%) (2). Moreover, fusing vegetation indices with multispectral data improved the OA from 75.1% to 79.3% in CNN (3). Further analysis revealed that shorter seedlings and tensors with a higher proportion of Cth-affected pixels have negative impacts on the OA in seedling forests. Based on the obtained results, the proposed method could be used to improve species classification of single-tree detected seedlings in operational forest inventory.

show abstract

Evaluating the effect of stand properties and site conditions on the forest reflectance from Sentinel-2 time series

Cited by 17 publications

References 86 publications

Influence of tree-crown density on dominant plant species of the herb-shrub stratum in the zone of mixed forests

Influence of tree-crown density on dominant plant species of the herb-shrub stratum in the zone of mixed forests

Forest Habitat Mapping in Natura2000 Regions in Cyprus Using Sentinel-1, Sentinel-2 and Topographical Features

A New Approach for Feeding Multispectral Imagery into Convolutional Neural Networks Improved Classification of Seedlings

Contact Info

Product

Resources

About