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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; 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 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 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; canopy height, etc ; center pivot irrigation; corn; grasses; plant growth; potatoes; surface irrigation; ultrasonics; water management; Show all 10 Subjects
Abstract:
... Center pivot irrigation systems are used globally to irrigate large fields. They have higher water application efficiency than other sprinkler or surface irrigation approaches, but this water application efficiency may be further improved by dynamically adjusting the nozzle height in response to plant growth and canopy heterogeneities; this approach is referred to as dynamic elevation spray applic ...
canopy; canopy height, etc ; forests; grasslands; image interpretation; land cover; landscapes; lidar; models; mountains; pastures; shrubs; topography; Show all 13 Subjects
Abstract:
... Publicly available land cover maps do not accurately represent shrubs and saplings, an uncommon but ecologically relevant cover type represented by woody vegetation <4 m tall. This omission likely occurs because (1) the resolution is too coarse, (2) poor training data are available, and/or (3) shrub/saplings are difficult to discriminate from spectrally similar classes. We present a framework for ...
... A microstand is a small forest area with a homogeneous tree species, height, and density composition. High-spatial-resolution GeoEye-1 multispectral (MS) images and GeoEye-1-based canopy height models (CHMs) allow delineating microstands automatically. This paper studied the potential benefits of two microstand segmentation workflows: (1) our modification of JSEG and (2) generic region merging (GR ...
canopy gaps; canopy height, etc ; Betula; Carpinus; administrative management; artificial regeneration; forest dynamics; geometry; models; species diversity; Poland; Show all 11 Subjects
Abstract:
... Forest dynamics is driven by the formation of gaps, especially in temperate forests. A potentially useful tool for identifying canopy gaps at different spatial scales is remote sensing. Our study used two types of data: (1) high spatial resolution Canopy Height Model (CHM) to detect canopy gaps in the forest and (2) field data to quantify natural and artificial regeneration within the gaps. The st ...
Keke Yu; Yang Liu; Zhaolong Gong; Yajun Liang; Lin Du; Zhenhua Zhang; Kexin Li; Sen Pang; Xueyuan Li; Lizhen Zhang; Weiming Tan; Mingwei Du; Xiaoli Tian; Zhaohu Li
... The cotton defoliation strategy is highly appreciated in Xinjiang, where mechanical harvesting is limited by a large proportion of green leaves and unopened bolls at harvest due to an insufficient temperature sum. Because of a high plant density, the application of defoliants (harvest aids) by tractors is less efficient; thus, unmanned aerial vehicles (UAVs) for spraying harvest aids are becoming ...
canopy height; forest canopy, etc ; aboveground biomass; autocorrelation; carbon sequestration; case studies; forest management; forests; geostatistics; kriging; lidar; satellites; uncertainty; Show all 13 Subjects
Abstract:
... Forest canopy height is an essential parameter in estimating forest aboveground biomass (AGB), growing stock volume (GSV), and carbon storage, and it can provide necessary information in forest management activities. Light direction and ranging (LiDAR) is widely used for estimating canopy height. Considering the high cost of acquiring LiDAR data over large areas, we took a two-stage up-scaling app ...
canopy; canopy height, etc ; global change; landscapes; lidar; lowlands; mortality; spatial data; topography; tree mortality; tropical rain forests; French Guiana; Show all 12 Subjects
Abstract:
... Several studies have shown an increase in tree mortality in intact tropical forests in recent decades. However, most studies are based on networks of field plots whose representativeness is debated. We examine the potential of repeated Airborne LiDAR Scanning data to map forest structure change over large areas with high spatial resolution and to detect tree mortality patterns at landscape level. ...
canopy height; forest canopy, etc ; coniferous forests; deciduous forests; decision support systems; lidar; mixed forests; models; synthetic aperture radar; topography; China; Show all 11 Subjects
Abstract:
... Spaceborne LiDAR has been widely used to obtain forest canopy heights over large areas, but it is still a challenge to obtain spatio-continuous forest canopy heights with this technology. In order to make up for this deficiency and take advantage of the complementary for multi-source remote sensing data in forest canopy height mapping, a new method to estimate forest canopy height was proposed by ...
canopy height; forest canopy, etc ; altimeters; carbon sequestration; climate change; environment; forest ecosystems; forest management; forests; ice; lidar; standard deviation; topography; China; Show all 14 Subjects
Abstract:
... Spatially continuous estimates of forest canopy height at national to global scales are critical for quantifying forest carbon storage, understanding forest ecosystem processes, and developing forest management and restoration policies to mitigate global climate change. Spaceborne light detection and ranging (lidar) platforms, especially the Global Ecosystem Dynamics Investigation (GEDI) and Ice, ...
canopy; canopy height, etc ; agriculture; corn; electronics; filling period; leaf area index; milk; models; plant growth; precision agriculture; seedlings; unmanned aerial vehicles; vegetation; Show all 14 Subjects
Abstract:
... As an important indicator reflecting plant growth and canopy structure, accurate and rapid monitoring of the leaf area index (LAI) is very important for modern precision agriculture. The purpose of this study is to explore the potential of fusion of morphological information and spectral information in multiple growth periods of maize to improve the accuracy of LAI dynamic estimation. The multi-sp ...
forest canopy, etc ; cameras; flight; forests; georeferencing; landscapes; lidar; Show all 7 Subjects
Abstract:
... In this paper we post-process and evaluate the position estimation of pairs of template windows and geo-referenced images generated from LiDAR cloud point data using the Normalized Cross-Correlation (NCC) method. We created intensity, surface and terrain pairs of images for use with template matching, with 5 m pixel spacing, through binning. We evaluated square and circular binning approaches, wit ...
canopy, etc ; hydrodynamics; research; submerged aquatic plants; vegetation; water; Show all 6 Subjects
Abstract:
... Vegetated canopies modify water conveyance and bed stabilization in aquatic ecosystems, providing shelter for other organisms. The sheltering effect downstream of a canopy is, however, rarely quantified for live vegetation, and it is unknown how this effect is influenced by vegetation patch configuration and characteristics. We measured the sheltering effect of different species and patch configur ...
canopy, etc ; Oryza sativa; models; reflectance; rice; vegetation index; Show all 6 Subjects
Abstract:
... Lodging stress influences the yield, quality, and mechanical harvesting ability of rice (Oryza sativa L.). It is of great significance for the quantitative and objective evaluation of rice yield loss to obtain the rice lodging distribution and grade information rapidly and nondestructively. The purpose of this paper was to establish a remote sensing monitoring method for the grade of rice lodging ...
canopy, etc ; algorithms; forests; lidar; linear models; prediction; Estonia; Show all 7 Subjects
Abstract:
... The goal of this study was to predict the need for commercial thinning using airborne lidar data (ALS) with random forest (RF) machine learning algorithm. Two test sites (with areas of 14,750 km² and 12,630 km²) were used with a total of 1053 forest stands from southwestern Estonia and 951 forest stands from southeastern Estonia. The thinnings were predicted based on the ALS measurements in 2019 a ...
canopy, etc ; Pinus banksiana; humus; rhizosphere; sand; soil density; Show all 6 Subjects
Abstract:
... The aim of the research was to identify the influence of environmental factors inherent in the alluvial and displaced sands of the study region on the growth of the Jack pine and the prospects for its cultivation. We found that the success of growth of Jack pine seedlings on sandy soils depends on a set of factors, which include the presence or absence, in the rhizosphere of sand, of humus impurit ...
canopy, etc ; case studies; cladding; energy; life cycle costing; taste; Show all 6 Subjects
Abstract:
... The design of building-integrated photovoltaic (BIPV) envelopes involves a large set of envelope-related parameters, PV-related parameters and conflicting performance criteria. Therefore, optimization of BIPV design is crucial and it has become a complex process. Existing BIPV design optimization frameworks lack BIPV product and application type-related variables, and most studies cannot handle la ...