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  • The role of leaf inclination, leaf orientation and plant canopy architecture in soil particle detachment by raindrops
  • Experimentation ; Plant canopy ; Rainfall simulation ; Soil erosion ; Splash ; Typology
  • The aim was to determine whether these morphological parameters are important predictors of soil detachment and should therefore be included in erosion models or whether, as is the case in many models, percentage canopy and canopy height alone
  • are adequate to represent the effects of vegetation. Since the role of canopy cover and canopy height is well recognized in erosion models, the experimental programme was designed within a relatively narrow range of values for these parameters so
  • Modeling land-surface albedos from vegetation canopy architecture
  • Canopy ; Climatology ; Deciduous forest ; Desert ; Forest ; Model ; Radiation ; United States ; Vegetation
  • A model of radiation transfer in plant canopies is used to predict vegetation albedos. The model is described and the results of simulations for three representative canopy types (tropical rainforest, Sonoran desert and mid-latitude deciduous forest
  • Estimation of canopy parameters for inhomogeneous vegetation canopies from reflectance data. II. Estimation of leaf area index and percentage of ground cover for row canopies
  • Bidirectional canopy and its relationship to vegetation characteristics
  • The technique involves three dimensional canopy reflectance surface in terms of spherical harmonics, weighted by coefficients (treated by cluster analysis). - (CB)
  • The variability of atmospheric deposition to forests. The effects of canopy structure and forest adges
  • The impact of forest canopy structure on deposition amounts was studied by extensive throughfall monitoring in thirty different forest stands in the Netherlands. It is concluded that emission reductions on a regional and (inter)national scale level
  • Atmospheric optical depth effects on angular anisotropy of plant canopy reflectance
  • Determine wether changes in atmospheric aerosol optical depth would effect changes in bi-directionnal reflectance distribution of vegetation canopies. The atmospheric optical depth must be considered for accurate remote sensing and in situ data
  • Radiation and energy flux characteristics of tea canopies in Kenya
  • This paper discusses the results of an experiment whereby all the major radiation and energy fluxes were measured/estimated for a mature tea canopy at Kericho, Kenya. The fluxes include incoming short-wave radiation, terrestrial radiation, latent
  • heat flux and the sensible heat fluxes between the canopy and the air and that into and out of the soil. The largest proportion of net radiation was consumed by the latent heat flux. Advection was found to be minimal.
  • PHOTOSYNTHESIS ON CANOPY LEAVES. COMMENT IN REPLY
  • AVHRR data processing to study the surface canopies in temperate regions. First results of HAPEX-MOBILHY in Special issue : Applications of AVHRR data.
  • The effect of shrub canopy upon surface temperatures and evaporation in the Negev Desert
  • and 1996-1997. Whereas evaporation was measured monthly using mini-atmometers at an exposed site and under and around the shrub, temperature was measured under a shrub canopy, at its northern aspect, and at an exposed habitat. Except from the northern
  • aspect, the under-canopy habitat showed substantially lower rates of evaporation in comparison with all other habitats. The differences between the under-canopy and the exposed habitat were larger during wintertime although higher differences
  • in temperatures characterized both habitats in summertime. The results were explained by extended surface wetness that characterized the under-canopy habitat following rainstorms. The substantially lower evaporation rates that characterize the under-canopy habitat
  • may thus play a pivotal role in providing preferential conditions for lush under-canopy annual growth.
  • Crop canopy spectral reflectance
  • Oblique view reflectance for assessing nitrogen status of incomplete canopies
  • Shear stress partitioning in sparsely vegetated desert canopies
  • Aeolian features ; Arid area ; Arizona ; Experimentation ; Plant canopy ; Semi-arid area ; Soil erosion ; United States of America ; Wasteland ; Wind erosion ; Wind speed
  • Shear velocity ratios were derived for 6 neighbouring localities representing rangeland, abandoned farmland and a playa, in the semi-arid region of the Sonoran Desert. Near-surface and above-canopy wind speeds, mostly below saltation threshold, were
  • used to evaluate the partitioning of shear velocities and shear stresses between the plant canopy and the surface. Results are discussed with the goal of assessing the protection provided by sparse vegetation against wind erosion.
  • Radial growth responses of three co-occuring species to small canopy disturbances in a secondary hardwood forest on the Cumberland Plateau, Tennessee
  • The AA. analyzed the radial growth patterns of Liriodendron tulipifera, Acer rubrum, and Acer saccharum growing in 39 canopy gaps in a mature secondary hardwood forest on the Cumberland Plateau in Tennessee to compare species-specific growth
  • responses to small canopy disturbances. They tested for differences between mean radial growth increases during the year of release initiation (i.e., first year of discernible growth increase) over the year prior, mean percent growth increases during
  • the year of release initiation over the year prior, mean release durations, and mean lag times between canopy gap formation and radial growth response. These findings provide information on the successional pathway of the forest, the physiological responses
  • of these species to small canopy openings, and the applicability of these species to reconstruct canopy gap formation in secondary stands from tree-ring records.
  • Tree-canopy characteristics and urban development in Hong Kong
  • Canopy ; Trees ; Urban area ; Urban development ; Urban landscape ; Urban planning
  • Microclimatic differences between and within canopy gaps in a temperate rainforest
  • Climate ; Forest ; Microclimate ; New Zealand ; Plant canopy ; Radiation ; Solar radiation ; Temperature
  • Laser altimetry or Light Detection And Ranging (LiDAR) technology provides horizontal and vertical information at high spatial resolutions and vertical accuracies. Forest attributes such as canopy height can be directly retrieved from LiDAR data
  • . Direct retrieval of canopy height provides opportunities to model above-ground biomass and canopy volume. Access to the vertical nature of forest ecosystems also offers new opportunities for enhanced forest monitoring, management and planning.
  • Relation between heat island intensity and city size indices/urban canopy characteristics in settlements of Nagano Basin, Japan
  • This paper demonstrates the relation between the heat island intensity and city size indices/urban canopy characteristics. This is accomplished by analyzing the data at 6 settlements on the Nagano basin. The AA. used population density, area
  • and their derivations in densely inhabited district as city size indices, and sky view factor, building land ratio and thermal admittance as urban canopy characteristics. Moreover, they examined the relation between the maximum heat island intensity and the population
  • Classification and ecology of closed-canopy forest in Ghana
  • Post-fire development of canopy structure in a mediterranean shrub, Quercus coccifera L.