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canopy, etc ; agronomy; apples; frost; frost injury; fruits; models; phenology; temperature; China; Show all 10 Subjects
Abstract:
... Frost damage during flowering is recognized as one of the most serious agro-meteorological disasters affecting apple production in Shaanxi province, a typical apple producing area in China. Quantitative assessments of flowering frost damage to apple yield are critical for the development of strategies on mitigating yield losses, but have been rarely conducted. For the first time, our study used th ...
canopy, etc ; anisotropy; case studies; normal distribution; standard deviation; turbulent flow; winter; China; Show all 8 Subjects
Abstract:
... The turbulent standard deviations and the turbulent third-order and fourth-order moments are the key turbulence dispersion parameters in Lagrangian dispersion models. However, the characteristics of these parameters under heavy haze conditions in urban areas have not been fully investigated, and the commonly used similarity relations of these parameters in models were based on observations in high ...
canopy, etc ; artificial intelligence; drought; industry; irrigation; model validation; phenotype; radiative transfer; remote sensing; summer; tomatoes; uncertainty; Show all 12 Subjects
Abstract:
... Drought management largely depends on the availability of timely, accurate and integrated information about its characteristics. Concurrently, biostimulants could represent a sustainable measure to foster the resilience of cropping systems under water-limited conditions. Nevertheless, scientific recognition of the potential of biostimulants has not grown as fast as the interest from industry: ther ...
canopy, etc ; Haloxylon ammodendron; Populus; carbohydrates; dieback; drought; drought tolerance; environment; field experimentation; leaf water potential; photosynthesis; stomatal conductance; water stress; Show all 13 Subjects
Abstract:
... In recent year, widespread declines of Populus bolleana Lauche trees (P. bolleana, which dieback from the top down) and Haloxylon ammodendron shrubs (H. ammodendron, which dieback starting from their outer canopy) have occurred. To investigate how both intra-canopy hydraulic changes and plasticity in hydraulic properties create differences in vulnerability between these two species, we conducted a ...
canopy, etc ; Berberis; Crataegus; ecosystems; flora; land cover; microclimate; semiarid zones; shrublands; soil fauna; soil quality; soil temperature; soil water; topsoil; Africa; Europe; Iran; North America; Show all 18 Subjects
Abstract:
... Crataegus and Berberis shrublands are natively distributed in Asia, Europe, North America and Africa. Despite the widespread distribution of these two species, the effect of pure and mixed canopy composition of these species on bioindicators of soil quality has received little attention. In the current research, the effect of pure [Crataegus (PC) and Berberis (PB)] and mixed [Crataegus and Berberi ...
canopy; canopy height, etc ; carbon dioxide; forests; hydrodynamics; meteorology; roughness; Show all 7 Subjects
Abstract:
... Understanding the processes that govern the mixing and transport of scalars within and above the Amazon Forest is of great importance for many environmental applications. The impact of atmospheric stability on the roughness sublayer (RSL) as well as the influence on it by the processes in the overlying atmosphere are investigated using measurements collected at the Atmospheric Tall Tower Observato ...
Harry Carstairs; Edward T. A. Mitchard; Iain McNicol; Chiara Aquino; Andrew Burt; Médard Obiang Ebanega; Anaick Modinga Dikongo; José-Luis Bueso-Bello; Mathias Disney
canopy; canopy height, etc ; aboveground biomass; carbon; satellites; topography; tropical forests; Gabon; Show all 8 Subjects
Abstract:
... Current satellite remote sensing methods struggle to detect and map forest degradation, which is a critical issue as it is likely a major and growing source of carbon emissions and biodiveristy loss. TanDEM-X InSAR phase height (hϕ) is a promising variable for measuring forest disturbances, as it is closely related to the mean canopy height, and thus should decrease if canopy trees are removed. Ho ...
canopy; canopy height, etc ; landscapes; models; snow; snowpack; summer; topographic slope; winter; Show all 9 Subjects
Abstract:
... The ICESat-2 ATL08 land and vegetation product includes several flags that can be used for the assessment of LiDAR-environment interactions and can help select data of the highest quality. However, the usability of these flags has not been sufficiently studied to date. Here, we aimed to evaluate the effects of atmospheric scattering, the presence of snow, canopy cover, terrain slope, beam strength ...
canopy; canopy height, etc ; Obukhov length; autocorrelation; forests; meteorology; turbulent flow; wind speed; Show all 8 Subjects
Abstract:
... Observations of the vertical structure of the turbulent flow in different stability regimes above and within the Amazon Forest at the Amazon Tall Tower Observatory (ATTO) site have been presented in Part I. Here, the influence of stability on the inception and development of coherent structures is investigated. According to the mixing-layer analogy the coherent vortices that dominate the turbulent ...
canopy height; forest canopy, etc ; altimeters; ice; landscapes; orthophotography; photons; topographic slope; trees; Show all 9 Subjects
Abstract:
... The Ice, Cloud, and Land Elevation Satellite–2 (ICESat–2) carries the Advanced Topographic Laser Altimeter System (ATLAS), enabling global canopy height measurements from forest canopy height models (CHMs). Topographic slope is a crucial factor affecting the accuracy of canopy height estimates from ICESat–2 CHMs, but it has not been sufficiently studied. This paper aims to eliminate the influence ...
canopy gaps; canopy height; forest canopy, etc ; Japan; aboveground biomass; analytical methods; ecosystems; forest stands; land use; landscapes; leaves; lidar; models; topography; trees; Show all 15 Subjects
Abstract:
... Spatial variations of maximum canopy height are key indicators of many ecosystem processes such as above-ground biomass and productivity. With rapid advances in remote sensing techniques, such as airborne laser scanning (ALS), we can now measure canopy height, tree density, and canopy gaps from local to large scales. But these data are yet to be fully exploited for a better understanding of canopy ...
canopy; canopy height, etc ; biodiversity; biomass; carbon; data collection; ecosystems; forests; lidar; models; reflectance; Show all 11 Subjects
Abstract:
... Spatially continuous canopy height is a vital input for modeling forest structures and functioning. The global ecosystem dynamics investigation (GEDI) waveform can penetrate a canopy to precisely find the ground and measure canopy height, but it is spatially discontinuous over the earth’s surface. A common method to achieve wall-to-wall canopy height mapping is to integrate a set of field-measured ...
canopy; canopy height, etc ; leaf area index; models; precision agriculture; unmanned aerial vehicles; wheat; Show all 7 Subjects
Abstract:
... Leaf area index (LAI), which is an important vegetation structure parameter, plays a crucial role in evaluating crop growth and yield. Generally, it is difficult to accurately estimate LAI only using vegetation index in remote sensing (RS), especially for unmanned aerial vehicle (UAV) based RS, as its high-resolution advantage has not been fully utilized. This study aims to propose an improved LAI ...
canopy height; forest canopy, etc ; biomass; carbon sequestration; forests; landscapes; lidar; models; mountains; uncertainty; Show all 10 Subjects
Abstract:
... Forest canopy height is one of the important forest parameters for accurately assessing forest biomass or carbon sequestration. ICESat-2 ATLAS provides the potential for retrieval of forest canopy height at global or regional scale, but the current canopy height product (ATL08) has coarse resolution and high uncertainty compared to airborne LiDAR-derived canopy height (hereafter ALCH) in mountaino ...
canopy gaps; canopy height; forest canopy, etc ; Weibull statistics; coasts; data collection; deciduous forests; flight; forest ecosystems; labor; landscapes; lidar; models; unmanned aerial vehicles; Taiwan; Show all 15 Subjects
Abstract:
... Canopy gaps are pivotal for monitoring forest ecosystem dynamics. Conventional field methods are time-consuming and labor intensive, making them impractical for regional mapping and systematic monitoring. Gaps may be delineated using airborne lidar or aerial photographs acquired from a manned aircraft. However, high cost in data acquisition and low flexibility in flight logistics significantly red ...
canopy; canopy height, etc ; Agamidae; algorithms; deforestation; geographical distribution; regression analysis; sympatry; topography; wood; India; Show all 11 Subjects
Abstract:
... AIM: In the absence of topographic barriers to dispersal, spatial boundaries of species are largely governed by the environmental regimes they occupy. Flying lizards (Agamidae: Draco) from peninsular India have surmounted prominent geographic barriers, but their northern distribution abruptly ends at the ‘Goa gap’, a latitudinal boundary separating the wet and dry regions of the Western Ghats. Giv ...
canopy; canopy height, etc ; carbon; leaf area index; leaves; models; nitrogen; phosphorus; spring; summer; winter; Show all 11 Subjects
Abstract:
... Monitoring the seasonal leaf nutrients of mangrove forests helps one to understand the dynamics of carbon (C) sequestration and to diagnose the availability and limitation of nitrogen (N) and phosphorus (P). To date, very little attention has been paid to mapping the seasonal leaf C, N, and P of mangrove forests with remote sensing techniques. Based on Sentinel-2 images taken in spring, summer, an ...
... The most active alkyne metathesis catalysts rely on well-defined Mo alkylidynes, X₃Mo≡CR (X = OR), in particular the recently developed canopy catalyst family bearing silanolate ligand sets. Recent efforts to understand catalyst reactivity patterns have shown that NMR chemical shifts are powerful descriptors, though previous studies have mostly focused on ligand-based NMR descriptors. Here, we sho ...
canopy; canopy height, etc ; Pterocarpus; coasts; hurricanes; lidar; rain; storm damage; trees; wind; Caribbean; Puerto Rico; Show all 12 Subjects
Abstract:
... Mangrove forests have unique ecosystem functions and services, yet the coastal mangroves in tropics are often disturbed by tropical cyclones. Hurricane Maria swept Puerto Rico and nearby Caribbean islands in September 2017 and caused tremendous damage to the coastal mangrove systems. Understanding the vulnerability and resistance of mangrove forests to disturbances is pivotal for future restoratio ...
canopy; canopy height, etc ; coniferous forests; data collection; forest inventory; models; stand density; standard deviation; trees; Show all 9 Subjects
Abstract:
... Numerous individual tree detection (ITD) methods have been developed for use with airborne laser scanning (ALS) data to provide tree-scale forest inventories across large spatial extents. Despite the growing number of methods, relatively few have been comparatively assessed using a single benchmark forest inventory validation dataset, limiting their operational application. In this study, we asses ...