scholarly journals Forest canopy, a proxi of light intensity, arrests Pinus radiata invasion: basic science to conserve the Coastal Maulino forest, Central Chile

2019 ◽  
Author(s):  
Persy Gómez ◽  
Maureen Murúa ◽  
José San Martín ◽  
Estefany Goncalves ◽  
Ramiro Bustamante
Keyword(s):  
Pinus Radiata ◽  
Forest Canopy ◽  
Forest Type ◽  
Canopy Cover ◽  
Structural Features ◽  
Important Variable ◽  
Tree Cover ◽  
Forest Fragments ◽  
Central Chile ◽  
Maulino Forest

ABSTRACTCoastal Maulino forest is an endemic forest of central Chile, which has suffered a large history of disturbance, being replaced by large extensions of Pinus radiata plantations. This land transformation conveys high rates of pines invasion into native remnants. In this study we examined to what extent structural features of forest patches explains invisibility of this forest-type. Within eight forest fragments, we sampled 162 plots (10 x 10 m2 each). We quantified seedling pine density and related this estimates with tree cover, litter depth, PAR radiation, and diversity of the resident community. Our results indicate that canopy cover was the most important variable to determine seedling pine density within forest fragments. To preserve the Coastal Maulino forest and the biodiversity containing on it, it seems to be necessary to maintain the native canopy cover. These actions can be highly effective even if we cannot avoid a massive seed arrival from pine plantations which will be unable to regenerate under well conserved native forests.

scholarly journals Shade-tree rehabilitation in vanilla agroforests is yield neutral and may translate into landscape-scale canopy cover gains

2020 ◽  
Author(s):  
Dominic A. Martin ◽  
Annemarie Wurz ◽  
Kristina Osen ◽  
Ingo Grass ◽  
Dirk Hölscher ◽  
...  
Keyword(s):  
Forest Canopy ◽  
Agricultural Landscape ◽  
Canopy Cover ◽  
Landscape Scale ◽  
Tree Cover ◽  
Ecosystem Functions ◽  
Forest Fragments ◽  
Forest Protection ◽  
Shade Tree ◽  
Open Land

Agroforestry can contribute to an increase in tree cover in historically forested tropical landscapes with associated gains in biodiversity and ecosystem functioning, but only if established on open land instead of underneath a forest canopy. However, declines in yields with increasing shade are common across agroforestry crops, driving shade-tree removal in forest-derived agroforests and hindering tree regrowth in open-land-derived agroforests. To understand trajectories of change in tree cover in forest- and open-land-derived agroforests and the impacts of tree cover on vanilla yields, we studied 209 vanilla agroforests along an 88-year chronosequence in Madagascar. Additionally, we used remotely-sensed canopy cover data to investigate tree cover change in the agricultural landscape. We found yields to vary widely but independently of canopy cover and land-use history (forest- vs. open-land-derived), averaging at 154.6 kg ha-1 yr-1 (SD = 186.9). Furthermore, we found that forest- and open-land-derived vanilla agroforests gained canopy cover over time, but that only open-land-derived agroforests gained canopy height. Canopy cover increased also at the landscape scale: areas in the agricultural landscape with medium initial canopy cover gained 6.4% canopy cover over 10 years, but canopy cover decreased in areas with high initial canopy cover. These opposing trends suggest tree cover rehabilitation across areas covered by vanilla agroforests, whereas remnant forest fragments in the agricultural landscape were transformed or degraded. Our results indicate that yield-neutral tree rehabilitation through open-land-derived agroforestry could, if coupled with effective forest protection, provide mutually beneficial outcomes for ecosystem functions and agricultural production in a smallholder-dominated agricultural landscape.

scholarly journals Shade-Tree Rehabilitation in Vanilla Agroforests is Yield Neutral and May Translate into Landscape-Scale Canopy Cover Gains

Ecosystems ◽  
2020 ◽  
Author(s):  
Dominic Andreas Martin ◽  
Annemarie Wurz ◽  
Kristina Osen ◽  
Ingo Grass ◽  
Dirk Hölscher ◽  
...  
Keyword(s):  
Forest Canopy ◽  
Agricultural Landscape ◽  
Canopy Cover ◽  
Landscape Scale ◽  
Tree Cover ◽  
Ecosystem Functions ◽  
Forest Fragments ◽  
Forest Protection ◽  
Shade Tree ◽  
Open Land

AbstractAgroforestry can contribute to an increase in tree cover in historically forested tropical landscapes with associated gains in biodiversity and ecosystem functioning, but only if established on open land instead of underneath a forest canopy. However, declines in yields with increasing shade are common across agroforestry crops, driving shade-tree removal in forest-derived agroforests and hindering tree regrowth in open-land-derived agroforests. To understand trajectories of change in tree cover in forest- and open-land-derived agroforests, and the impacts of tree cover on vanilla yields, we studied 209 vanilla agroforests along an 88-year chronosequence in Madagascar. Additionally, we used remotely sensed canopy cover data to investigate tree cover change in the agricultural landscape. We found yields to vary widely but independently of canopy cover and land-use history (forest- vs. open-land-derived), averaging at 154.6 kg ha−1 year−1 (SD = 186.9). Furthermore, we found that forest- and open-land-derived vanilla agroforests gained canopy cover over time, but that only open-land-derived agroforests gained canopy height. Canopy cover increased also at the landscape scale: areas in the agricultural landscape with medium initial canopy cover gained 6.4% canopy cover over 10 years, but canopy cover decreased in areas with high initial canopy cover. These opposing trends suggest tree cover rehabilitation across areas covered by vanilla agroforests, whereas remnant forest fragments in the agricultural landscape were transformed or degraded. Our results indicate that yield-neutral tree rehabilitation through open-land-derived agroforestry could, if coupled with effective forest protection, provide benefits for both ecosystem functions and agricultural production in a smallholder-dominated agricultural landscape.

scholarly journals Estimating Forest Canopy Cover in Black Locust (Robinia pseudoacacia L.) Plantations on the Loess Plateau Using Random Forest

Forests ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 623 ◽  
Author(s):  
Qingxia Zhao ◽  
Fei Wang ◽  
Jun Zhao ◽  
Jingjing Zhou ◽  
Shichuan Yu ◽  
...  
Keyword(s):  
Random Forest ◽  
Loess Plateau ◽  
Forest Canopy ◽  
Vegetation Index ◽  
Black Locust ◽  
Robinia Pseudoacacia ◽  
Canopy Cover ◽  
Window Size ◽  
Important Variable ◽  
The Loess Plateau

The forest canopy is the medium for energy and mass exchange between forest ecosystems and the atmosphere. Remote sensing techniques are more efficient and appropriate for estimating forest canopy cover (CC) than traditional methods, especially at large scales. In this study, we evaluated the CC of black locust plantations on the Loess Plateau using random forest (RF) regression models. The models were established using the relationships between digital hemispherical photograph (DHP) field data and variables that were calculated from satellite images. Three types of variables were calculated from the satellite data: spectral variables calculated from a multispectral image, textural variables calculated from a panchromatic image (Tpan) with a 15 × 15 window size, and textural variables calculated from spectral variables (TB+VIs) with a 9 × 9 window size. We compared different mtry and ntree values to find the most suitable parameters for the RF models. The results indicated that the RF model of spectral variables explained 57% (root mean square error (RMSE) = 0.06) of the variability in the field CC data. The soil-adjusted vegetation index (SAVI) and enhanced vegetation index (EVI) were more important than other spectral variables. The RF model of Tpan obtained higher accuracy (R2 = 0.69, RMSE = 0.05) than the spectral variables, and the grey level co-occurrence matrix-based texture measure—Correlation (COR) was the most important variable for Tpan. The most accurate model was obtained from the TB+VIs (R2 = 0.79, RMSE = 0.05), which combined spectral and textural information, thus providing a significant improvement in estimating CC. This model provided an effective approach for detecting the CC of black locust plantations on the Loess Plateau.

Distribution of herbs and shrubs in relation to landform and canopy cover in riparian forests of coastal Oregon

1998 ◽  
Vol 76 (2) ◽  
pp. 298-315 ◽  
Author(s):  
Robert J Pabst ◽  
Thomas A Spies
Keyword(s):  
Forest Canopy ◽  
Mineral Soil ◽  
Canopy Cover ◽  
Soil Disturbance ◽  
Environmental Data ◽  
Valley Floor ◽  
Conservation Strategy ◽  
Tree Cover ◽  
Species Groups ◽  
Underlying Mechanisms

In this study we characterized the distribution of herb and shrub species relative to landform and forest canopy attributes of streamside forests in the moist, conifer-dominated mountains of coastal Oregon. Species cover and environmental data were collected along transects at 94 sites. Species with relatively similar distributions were classified into 10 species groups to identify major patterns in the vegetation. Although these patterns were highly variable, ordination and gradient analyses indicated that vegetation composition is ordered along a complex environmental gradient running from streamside to hillslope. Similarly, species diversity followed a decreasing trend from active fluvial surfaces to lower hillslopes. Vegetation patterns were related to specific landforms, topographic positions, microsites, and coniferous tree cover within the trans-riparian gradient. We hypothesize that the environmental features correlated with these patterns are surrogates for the underlying mechanisms responsible for them. These are (i) hillslope processes and associated moisture gradients; (ii) hydrological disturbance; (iii) tolerance of saturated, valley-floor soils; (iv) shade tolerance; and (v) mineral soil disturbance. This study indicates that valley-floor and lower-slope plant communities are distinct elements in these forest landscapes, supporting the assumption that riparian zones require a different management and conservation strategy than upland forest communities.Key words: riparian vegetation, ordination, gradient analysis, species groups, landform. Nomenclature is based on that of Hitchcock and Cronquist (1973).

scholarly journals Gainesville's Urban Forest Canopy Cover

EDIS ◽  
2009 ◽  
Vol 2009 (3) ◽  
Author(s):  
Francisco Escobedo ◽  
Jennifer A. Seitz ◽  
Wayne Zipperer
Keyword(s):  
Forest Canopy ◽  
Urban Forest ◽  
Ground Surface ◽  
Canopy Cover ◽  
Tree Cover ◽  
Urban Tree ◽  
Changes Over Time ◽  
Urban Tree Cover ◽  
Tree Composition ◽  
Over Time

FOR-215, a 3-page illustrated fact sheet by Francisco Escobedo, Jennifer A. Seitz, and Wayne Zipperer, examines how tree cover changes over time, how tree composition and location influence urban forest canopy and leaf area, and how tree and ground surface covers vary across Gainesville. Includes references. Published by the UF School of Forest Resources and Conservation, March 2009.   FOR 215/FR277: Gainesville Florida's Urban Tree Cover (ufl.edu)  

scholarly journals A Comparative Study to Evaluate Accuracy on Canopy Height and Density Using UAV, ALS, and Fieldwork

Forests ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 241 ◽  
Author(s):  
Cheonggil Jin ◽  
Che-young Oh ◽  
Sanghyun Shin ◽  
Nkwain Wilfred Njungwi ◽  
Chuluong Choi
Keyword(s):  
Forest Canopy ◽  
Forest Type ◽  
Canopy Cover ◽  
Tree Height ◽  
Field Measurements ◽  
Point Clouds ◽  
Aerial Photographs ◽  
Measurement Unit ◽  
Maximum Height ◽  
Cover Density

Accurate measurement of the tree height and canopy cover density is important for forest biomass and management. Recently, Light Detection and Ranging (LIDAR) and Unmanned Aerial Vehicle (UAV) images have been used to estimate the tree height and canopy cover density for a forest stands. More so, UAV systems with autopilot functions, affordable Global Navigation Satellite System (GNSS) and Inertial Measurement Unit (IMU) have created new possibilities, aided by available photogrammetric programs. In this study, we investigated the possibility of data collection methods using an Aerial LIDAR Scanner (ALS) and an UAV together with a fieldworks to evaluate accurate the tree standard metrics in Singyeri, Gyeongjusi, and Gyeongsangbukdo province. The derived metrics via statistical analyses of the ALS and UAV data and validated by field measurements were compared to a published forest type map (scale 1:5000) by the Korea Forest Service; geared towards improving the forest attributes. We collected data and analyzed and compared them with existent the forest type map produced from an aerial photographs and a digital stereo plotter. The ALS data of around 19.5 points·m–2 were collected by an airplane, then processed and classified using the LAStools; while about 362 images of the UAV were processed via Structure from Motion algorithm in the Agisoft Metashape Pro. Thus, we calculated the metrics using the point clouds of both an ALS and an UAV, and then verified their similarity. The fieldwork was manually done on 110 sampled trees. Calculated heights of the UAV were 3.8~5.8 m greater than those for the ALS; and when correlated with the fieldwork, the UAV data overestimated, while the maximum height of the ALS data was more accurate. For the canopy cover, the ALS computed canopy cover was 10%~30% less than that of the UAV. However, the canopy cover above 2 m by an UAV was the best measurement for a forest canopy. Therefore, these results assert that the examined techniques are robust and can significantly complement methods of the conventional data acquisition for the forest type map.

Patterns in woody vegetation cover across forests of a main Mediterranean island in relation to precipitation regime.

2021 ◽  
Author(s):  
Sara Simona Cipolla ◽  
Nicola Montaldo
Keyword(s):  
Forest Canopy ◽  
Forest Type ◽  
Temporal Trends ◽  
Tree Cover ◽  
Mean Annual Precipitation ◽  
Precipitation Regime ◽  
Soil Thickness ◽  
Precipitation Regimes ◽  
Woody Cover ◽  
Cover Density

<p><span>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.</span> <span>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.</span></p>

scholarly journals Potential improvement for forest cover and forest degradation mapping with the forthcoming Sentinel-2 program

2015 ◽  
Vol XL-7/W3 ◽  
pp. 417-423 ◽  
Author(s):  
L. Hojas-Gascon ◽  
A. Belward ◽  
H. Eva ◽  
G. Ceccherini ◽  
O. Hagolle ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Forest Canopy ◽  
Forest Cover ◽  
Spectral Characteristics ◽  
Canopy Cover ◽  
Tree Cover ◽  
Optical Data ◽  
Validation Data ◽  
The Impact ◽  
Sentinel 2

The forthcoming European Space Agency’s Sentinel-2 mission promises to provide high (10 m) resolution optical data at higher temporal frequencies (5 day revisit with two operational satellites) than previously available. CNES, the French national space agency, launched a program in 2013, ‘SPOT4 take 5’, to simulate such a dataflow using the SPOT HRV sensor, which has similar spectral characteristics to the Sentinel sensor, but lower (20m) spatial resolution. Such data flow enables the analysis of the satellite images using temporal analysis, an approach previously restricted to lower spatial resolution sensors. We acquired 23 such images over Tanzania for the period from February to June 2013. The data were analysed with aim of discriminating between different forest cover percentages for landscape units of 0.5 ha over a site characterised by deciduous intact and degraded forests. The SPOT data were processed by one extracting temporal vegetation indices. We assessed the impact of the high acquisition rate with respect to the current rate of one image every 16 days. Validation data, giving the percentage of forest canopy cover in each land unit were provided by very high resolution satellite data. Results show that using the full temporal series it is possible to discriminate between forest units with differences of more than 40% tree cover or more. Classification errors fell exclusively into the adjacent forest canopy cover class of 20% or less. The analyses show that forestation mapping and degradation monitoring will be substantially improved with the Sentinel-2 program.

scholarly journals Forest canopy-cover composition and landscape influence on bryophyte communities in Nothofagus forests of southern Patagonia

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0232922
Author(s):  
Mónica D. R. Toro Manríquez ◽  
Víctor Ardiles ◽  
Álvaro Promis ◽  
Alejandro Huertas Herrera ◽  
Rosina Soler ◽  
...  
Keyword(s):  
Forest Canopy ◽  
Forest Type ◽  
Canopy Cover ◽  
Tierra Del Fuego ◽  
Environmental Drivers ◽  
Forest Types ◽  
Coastal Forests ◽  
Additional Species ◽  
Evergreen Forests ◽  
Southern Patagonia

Bryophytes (liverworts, mosses and hornworts) are one of the most diverse plant groups worldwide but one of the least studied in temperate forests from an ecological perspective. In comparison to vascular plants, bryophytes have a broader distribution and a longer altitudinal gradient, and their influence on the landscape is poorly understood. The objective was to evaluate environmental drivers that can influence bryophyte cover, richness, diversity, and nestedness in different forest canopy compositions in two typical landscapes across the natural distribution of bryophytes in Tierra del Fuego (Argentina). Three natural Nothofagus forest types (pure deciduous, pure evergreen, and mixed deciduous-evergreen) in two landscapes (coasts < 100 m.a.s.l. and mountains > 400 m.a.s.l.) were selected (N = 60 plots). In each plot, we established one transect (10 m length) to measure bryophyte cover (point-intercept method). Data were evaluated using generalized linear mixed models and multivariate analyses. The studied environmental drivers were mainly explained by the microclimate, with higher effective annual precipitation and relative air humidity in the coastal forests and higher soil moisture in the mountain forests. Greater liverwort richness was found in evergreen forests at the mountain (9 species) than at the coastal, while mosses showed higher richness in mixed deciduous-evergreen forests at the coastal (11 species) than at the mountain. However, the expected richness according to the rarefaction/extrapolation curves suggested that it is possible to record additional species, except for liverworts in pure deciduous forests on the coasts. Similarities and differences among the studied forest types and among plots of the same forest type and landscape were detected. These differences in the studied indexes (similarity that varied between 0 and 1) ranged from 0.09–0.48 for liverworts and 0.05–0.65 for mosses. Moreover, these results indicated that pure evergreen and mixed deciduous-evergreen forests presented higher moss cover (10.7% and 10.0%, respectively), mainly in the mountains than on the coast. These outputs highlight the need to explore differences at greater altitudinal ranges to achieve sustainability objectives conservation planning for bryophytes in southernmost forests.

scholarly journals Diversity of Medicinal Plants among Different Tree Canopies

2021 ◽  
Vol 13 (5) ◽  
pp. 2640
Author(s):  
Muhammad Zubair ◽  
Akash Jamil ◽  
Syed Bilal Hussain ◽  
Ahsan Ul Haq ◽  
Ahmad Hussain ◽  
...  
Keyword(s):  
Medicinal Plants ◽  
Coniferous Forest ◽  
Canopy Cover ◽  
Local Communities ◽  
Tree Canopy ◽  
Tree Cover ◽  
Open Spaces ◽  
Floral Diversity ◽  
Tree Canopy Cover ◽  
Closed Canopy

The moist temperate forests in Northern Pakistan are home to a variety of flora and fauna that are pivotal in sustaining the livelihoods of the local communities. In these forests, distribution and richness of vegetation, especially that of medicinal plants, is rarely reported. In this study, we carried out a vegetation survey in District Balakot, located in Northeastern Pakistan, to characterize the diversity of medicinal plants under different canopies of coniferous forest. The experimental site was divided into three major categories (viz., closed canopy, open spaces, and partial tree cover). A sampling plot of 100 m2 was established on each site to measure species diversity, dominance, and evenness. To observe richness and abundance, the rarefaction and rank abundance curves were plotted. Results revealed that a total of 45 species representing 34 families were available in the study site. Medicinal plants were the most abundant (45%) followed by edible plants (26%). Tree canopy cover affected the overall growth of medicinal plants on the basis of abundance and richness. The site with partial canopy exhibited the highest diversity, dominance, and abundance compared to open spaces and closed canopy. These findings are instrumental in identifying the wealth of the medicinal floral diversity in the northeastern temperate forest of Balakot and the opportunity to sustain the livelihoods of local communities with the help of public/private partnership.

Sign in / Sign up

Export Citation Format

Share Document