Prediction of snow-water equivalents in coniferous forests

1981 ◽  
Vol 11 (4) ◽  
pp. 854-857 ◽  
Author(s):  
Alton S. Harestad ◽  
Fred L. Bunnell
Keyword(s):  
Canopy Cover ◽  
Relative Influence ◽  
Coniferous Forests ◽  
Forest Canopies ◽  
Forested Areas ◽  
Snow Water ◽  
The Difference

Less snow accumulates under forest canopies than in small openings. Analysis of relationships between canopy cover and snow-water equivalents (SWE) for coniferous forests indicate substantial differences between areas and years. Many of these differences result from differences in the total amount of snowfall. The difference between SWE values in open and forested areas increases with increasing SWE in the open. However, the relative influence of canopy cover on maximum SWE decreases with increasing SWE in open areas. By incorporating this latter relationship, canopy cover can be used to predict snow-water equivalents in coniferous forests.

scholarly journals Altitude and Canopy Cover Effects on Air Temperature in a Mountainous Region of Ionian Islands, Greece

2018 ◽  
Vol 13 (3) ◽  
pp. 292-298
Author(s):  
ATHANASIOS KAMOUTSIS ◽  
KOSTAS CHRONOPOULOS ◽  
ARISTIDIS MATSOUKIS
Keyword(s):  
Air Temperature ◽  
Canopy Cover ◽  
Decisive Role ◽  
Thermal Conditions ◽  
Special Importance ◽  
Mean Values ◽  
Ionian Islands ◽  
Hiking Trails ◽  
Forested Areas ◽  
Of Greece

Topography and canopy play a decisive role on air temperature (T) conditions in forested areas. Air temperature is a crucial factor in decision making process for the development of these areas. To our knowledge, there is no information regarding the effect of topography along with canopy cover (Pc) on thermal conditions of a vulnerable mountainous forested region of Greece, Mount (Mt) Aenos in the island of Cephalonia, Ionian Islands, Greece. Therefore, the purpose of our work is the investigation of the aforementioned parameters, especially the effect of altitude (alt) and Pc on T of Mt Aenos. Mean values for maximum air temperature (Tx) and Pc were estimated for twelve sites at various alts in Mt Aenos during the period May-October of three consecutive years (2011-2013). The analysis of the results showed that Tx was related to alt and Pc. Altitude has a greater effect on T in relation to Pc. When examining same or similar alts, an increase of Pc up to 51% resulted in a significant decrease of Tx (p<0.05) up to 3.6 °C. Our findings could be taken into account in planning the construction of hiking trails for recreational activities in Mt Aenos, and, in general, in mountainous forest areas of special importance.

scholarly journals Fusing Sentinel-2 Imagery and ALS Point Clouds for Defining LULC Changes on Reclaimed Areas by Afforestation

2019 ◽  
Vol 11 (5) ◽  
pp. 1251 ◽  
Author(s):  
Marta Szostak ◽  
Kacper Knapik ◽  
Piotr Wężyk ◽  
Justyna Likus-Cieślik ◽  
Marcin Pietrzykowski
Keyword(s):  
Laser Scanning ◽  
Canopy Cover ◽  
Point Clouds ◽  
Test Site ◽  
Vegetation Growth ◽  
Landsat 7 ◽  
Forested Areas ◽  
Primary Focus ◽  
Year 2000 ◽  
Sentinel 2

The study was performed on two former sulphur mines located in Southeast Poland: Jeziórko, where 216.5 ha of afforested area was reclaimed after borehole exploitation and Machów, where 871.7 ha of dump area was reclaimed after open cast strip mining. The areas were characterized by its terrain structure and vegetation cover resulting from the reclamation process. The types of reclamation applied in these areas were forestry in Jeziórko and agroforestry in the Machów post-sulphur mine. The study investigates the possibility of applying the most recent Sentinel-2 (ESA) satellite imageries for land cover mapping, with a primary focus on detecting and monitoring afforested areas. Airborne laser scanning point clouds were used to derive precise information about the spatial (3D) characteristics of vegetation: the height (95th percentile), std. dev. of relative height, and canopy cover. The results of the study show an increase in afforested areas in the former sulphur mines. For the entire analyzed area of Jeziórko, forested areas made up 82.0% in the year 2000 (Landsat 7, NASA), 88.8% in 2009 (aerial orthophoto), and 95.5% in 2016 (Sentinel-2, ESA). For Machów, the corresponding results were 46.1% in 2000, 57.3% in 2009, and 60.7% in 2016. A dynamic increase of afforested area was observed, especially in the Jeziórko test site, with the presence of different stages of vegetation growth.

Remote Sensing of Forest Fire Severity and Vegetation Recovery

1996 ◽  
Vol 6 (3) ◽  
pp. 125 ◽  
Author(s):  
JD White ◽  
KC Ryan ◽  
CC Key ◽  
SW Running
Keyword(s):  
Satellite Data ◽  
Fire Severity ◽  
Canopy Cover ◽  
Burn Severity ◽  
Vegetation Recovery ◽  
Electromagnetic Spectrum ◽  
Vegetation Types ◽  
Burned Areas ◽  
Before And After ◽  
Forested Areas

Burned forested areas have patterns of varying burn severity as a consequence of various topographic, vegetation, and meteorological factors. These patterns are detected and mapped using satellite data. Other ecological information can be abstracted from satellite data regarding rates of recovery of vegetation foliage and variation of burn severity on different vegetation types. Middle infrared wavelengths are useful for burn severity mapping because the land cover changes associated with burning increase reflectance in this part of the electromagnetic spectrum. Simple stratification of Landsat Thematic Mapper data define varying classes of burn severity because of changes in canopy cover, biomass removal, and soil chemical composition. Reasonable maps of burn severity are produced when the class limits of burn severity reflectance are applied to the entire satellite data. Changes in satellite reflectance over multiple years reveal the dynamics of vegetation and fire severity as low burn areas have lower changes in reflectance relative to high burn areas. This results as a consequence of how much the site was altered due to the burn and how much space is available for vegetation recovery. Analysis of change in reflectance across steppe, riparian, and forested vegetation types indicate that fires potentially increase biomass in steppe areas, while riparian and forested areas are slower to regrow to pre-fire conditions. This satellite-based technology is useful for mapping severely burned areas by exploring the ecological manifestations before and after fire.

Autecology of Erythronium grandiflorum in western Canada

2001 ◽  
Vol 79 (4) ◽  
pp. 500-509 ◽  
Author(s):  
Dawn C Loewen ◽  
Geraldine A Allen ◽  
Joseph A Antos
Keyword(s):  
Canopy Cover ◽  
Detrended Correspondence Analysis ◽  
Coniferous Forests ◽  
Deciduous Trees ◽  
Growth Stages ◽  
Western Canada ◽  
Percent Cover ◽  
Subalpine Meadows ◽  
Associated Species ◽  
Erythronium Grandiflorum

Habitat requirements of the yellow glacier lily, Erythronium grandiflorum Pursh, were studied at 38 sites in southern British Columbia and southwestern Alberta. At each site we recorded densities of E. grandiflorum growth stages from seedling to flowering, environmental characteristics of the site, and percent cover of associated plant species. We carried out detrended correspondence analysis (DCA) of the sites based on cover of associated species, and examined rank correlations between site environmental variables and site ordination scores. Variation among sites was related primarily to elevation and the presence of deciduous vs. coniferous trees. All growth stages of E. grandiflorum were less abundant in coniferous forests than in open areas or sites with deciduous trees, suggesting that evergreen canopies restrict the species on many sites where it could otherwise grow. Although E. grandiflorum populations were most commonly found in subalpine meadows, they flowered more abundantly in low-elevation populations. Recruitment was frequent, with seedlings occurring at many sites; we also showed that detached bulb segments can give rise to new ramets. The present widespread distribution of E. grandiflorum may derive from a post-glacial period with extensive meadow habitat that was favourable for rapid spread.Key words: canopy cover, elevation, yellow glacier lily, post-glacial migration, subalpine meadows.

Relative Influence of Linguistic versus Cultural Factors on Free Verbal Associations

1968 ◽  
Vol 22 (1) ◽  
pp. 43-51 ◽  
Author(s):  
Lorand B. Szalay ◽  
Charles Windle
Keyword(s):  
Language Acquisition ◽  
Cultural Background ◽  
Cultural Factors ◽  
Relative Influence ◽  
Cultural Groups ◽  
Word Associations ◽  
Word Meanings ◽  
The Difference ◽  
Free Word

The extent to which differences in word associations between cultural groups are due to linguistic factors or to word meanings and values determined by culture was examined in the continued free word associations of Koreans in Korean and in English and a U. S. group in English. The influence of cultural background was at least as much as that of language on each of three characteristics examined. Further, much of the difference due to language seems to stem from the milieu of language acquisition.

Factors influencing the pattern of fire severities in a large wildfire under extreme meteorological conditions in the Mediterranean basin

2009 ◽  
Vol 18 (7) ◽  
pp. 755 ◽  
Author(s):  
Imma Oliveras ◽  
Marc Gracia ◽  
Gerard Moré ◽  
Javier Retana
Keyword(s):  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Fire Severity ◽  
Fire Behavior ◽  
Negative Relationship ◽  
Canopy Cover ◽  
Mediterranean Ecosystems ◽  
Meteorological Conditions ◽  
Landsat Images ◽  
The Difference

In Mediterranean ecosystems, large fires frequently burn under extreme meteorological conditions, but they are usually characterized by a spatial heterogeneity of burn severities. The way in which such mixed-severity fires are a result of fuels, topography and weather remains poorly understood. We computed fire severity of a large wildfire that occurred in Catalonia, Spain, as the difference between the post- and pre-fire Normalized Difference Vegetation Index (NDVI) values obtained through Landsat images. Fuel and topographic variables were derived from remote sensing, and fire behavior variables were obtained from an exhaustive reconstruction of the fire. Results showed that fire severity had a negative relationship with percentage of canopy cover, i.e. green surviving plots were mainly those with more forested conditions. Of the topographic variables, only aspect had a significant effect on fire severity, with higher values in southern than in northern slopes. Fire severity was higher in head than in flank and back fires. The interaction of these two variables was significant, with differences between southern and northern aspects being small for head fires, but increasing in flank and back fires. The role of these variables in determining the pattern of fire severities is of primary importance for interpreting the current landscapes and for establishing effective fire prevention and extinction policies.

Seedbed and canopy cover effects on balsam fir seedling establishment in Isle Royale National Park

1996 ◽  
Vol 26 (5) ◽  
pp. 782-793 ◽  
Author(s):  
Brian E. McLaren ◽  
Robert A. Janke
Keyword(s):  
Seedling Establishment ◽  
National Park ◽  
Seedling Survival ◽  
Canopy Cover ◽  
Balsam Fir ◽  
Isle Royale ◽  
Isle Royale National Park ◽  
Rotten Wood ◽  
The Difference ◽  
Overwinter Mortality

While balsam fir (Abiesbalsamea (L.) Mill.) dominated forests are vanishing from the southwest end of Isle Royale National Park, Michigan, renewal of fir stands is occurring on the northeast end. We speculate that the difference is related both to severe browsing by moose (Alcesalces L.), and to the frequency of disturbances like fire and windthrow. A survey of 24 stands and in situ experimentation on Isle Royale show that balsam fir seedling survival is optimal under 40–79% canopy cover. Late-season and overwinter mortality in 1-year-old seedlings is highest under >80% canopy cover, while germination is lowest under <40% cover. We also rank germination substrates by "preference ratios," and by comparing the overwinter survival of young fir seedlings on five natural media. We find best performance on hypnaceous moss, variable survival success on rotten wood, and highest mortality on broadleaf litter. However, ample seedling densities occur on the southwest end of the island, and the failure of fir to reach the overstory in this area is apparently not related to poor seedling establishment.

Unexpected global patterns in plant vulnerability to climate change

2021 ◽  
Author(s):  
Alexander Tomas Sentinella ◽  
William B. Sherwin ◽  
Catherine A. Offord ◽  
Angela Moles
Keyword(s):  
Climate Change ◽  
At Risk ◽  
High Risk ◽  
Canopy Cover ◽  
Factors Associated ◽  
Tropical Environments ◽  
Vulnerability To Climate Change ◽  
Tropical Grasslands ◽  
Upper Limits ◽  
The Difference

Understanding how species will respond to climate change is critically important for managing our ecosystems into the future. However, surprisingly little is known about the distribution of risk based on the actual thermal tolerances of species, especially plants. We used germination records from 776 species to provide a global map of plant warming risk – the difference between maximum germination temperature and the predicted 2070 temperature. We then tested a series of hypotheses about factors associated with high risk. Many of our predictions were overturned. For example, although a great deal of attention has been paid to the risks faced by tropical forests, we found that the biomes most at risk were tropical grasslands, savannas and shrublands. Similarly, while we expected Australian species to have a lower warming risk due to its already variable conditions, our data showed that Australia had the highest average warming risk. Conversely, European species faced the lowest risk, with no plants examined in this study predicted to exceed their upper limits by 2070. Plants from regions with higher seasonality and higher canopy cover had lower warming risk, but the absolute range of annual temperature had no effect on risk. Therefore, the underlying factors contributing to warming risk warrant further examination. Overall, our results highlight that the regions most at risk from warming are not necessarily those with the most warming, but regions where species are closest to their upper limits. More attention needs to be given to high risk tropical environments, especially non-forest tropical environments which face the highest risk. In summary, while much of the world’s biota faces substantial threats from climate change, researchers may be surprised about where the effects are most acute.

Tardigrades in the Canopy: Associations with Tree Vole Nests in Southwest Oregon

2020 ◽  
Author(s):  
John Villella ◽  
Jesse E. D. Miller ◽  
Alexander Young ◽  
Greg Carey ◽  
Andrew Emanuels ◽  
...  
Keyword(s):  
Pacific Northwest ◽  
Environmental Variables ◽  
Forest Canopy ◽  
Coniferous Forests ◽  
Forest Canopies ◽  
Species Numbers ◽  
The Pacific ◽  
Southwest Oregon ◽  
East West ◽  
Local Dispersal

Tardigrades live in many ecosystems, but local dispersal mechanisms and the influence of ecological gradients on tardigrade communities are not fully understood. Here we examine tardigrade communities in nests of the red tree vole (Arborimus longicaudus True), an arboreal mammal occupying the canopy of coniferous forests in western Oregon and northwestern California. We found 12 species of tardigrades from resin ducts sampled from 43 nests along a transect that spanned the east-west range of the tree vole in southern Oregon. Tardigrade occurrence was more likely in larger trees and species numbers were significantly higher in areas that received more precipitation. At sites where they occurred, tardigrades were more abundant in tree vole nests at greater heights within the forest canopy. Of the 12 species of tardigrades that were found, seven have not been previously reported in Oregon. Our results suggest that tardigrades in forest canopies in the Pacific Northwest are impacted by regional precipitation gradients as well as local environmental variables, and that nest building by small mammals may facilitate dispersal of tardigrades within the forest canopy.

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