Remote sensing of subtropical tree diversity: The underappreciated roles of the practical definition of forest canopy and phenological variation DOI Creative Commons
Yongchao Liu, Ruyun Zhang, Chen‐Feng Lin

et al.

Forest Ecosystems, Journal Year: 2023, Volume and Issue: 10, P. 100122 - 100122

Published: Jan. 1, 2023

Tree species diversity is vital for maintaining ecosystem functions, yet our ability to map the distribution of tree limited due difficulties in traditional field-based approaches. Recent developments spaceborne remote sensing provide unprecedented opportunities and monitor more efficiently. Here we built partial least squares regression models using multispectral surface reflectance acquired by Sentinel-2 satellites inventory data from 74 subtropical forest plots predict canopy a national natural reserve eastern China. In particular, evaluated underappreciated roles practical definition phenological variation predicting testing three different definitions trees comparing satellite imagery seasons. Our best explained 42%–63% variations observed diversities cross-validation tests, with higher explanation power indices that are sensitive abundant species. The imageries early spring late autumn showed consistently better fits than those other seasons, highlighting significant role transitional phenology remotely plant diversity. results suggested cumulative diameter (60%–80%) biggest way define layer subjective fixed-diameter-threshold (5–12 ​cm) or basal area (90%–95%) trees. Remarkably, these approaches resulted contrasting maps call attention structure This study demonstrates potential mapping monitoring Sentinal-2 species-rich forests.

Language: Английский

Linking aerial hyperspectral data to canopy tree biodiversity: An examination of the spectral variation hypothesis DOI Creative Commons
Anna L. Crofts, Christine I.B. Wallis, Sabine St‐Jean

et al.

Ecological Monographs, Journal Year: 2024, Volume and Issue: 94(3)

Published: May 6, 2024

Abstract Imaging spectroscopy is emerging as a leading remote sensing method for quantifying plant biodiversity. The spectral variation hypothesis predicts that in hyperspectral reflectance related to taxonomic and functional identity. While most studies report some correlation between field‐based (i.e., functional) expressions of biodiversity, the observed strength association highly variable, utility applying community properties examine environmental drivers communities remains unknown. We linked data acquired by airborne imaging spectrometers with precisely geolocated field plots along temperate‐to‐boreal forest gradient southern Québec, Canada. First, we degree dimensions canopy tree composition diversity. Second, ask whether relationships environment are reproduced when using properties. found support generally greater than dimension, but was variable dependent on choice or metric used quantify Using multivariate approach (comparisons separate ordinations), moderately well correlated composition; however, increased univariately relating main axes compositional variation. Spectral diversity tightly associated metrics richness divergence. For predicting variables, same qualitative conclusions emerge used. Spatial patterns were strongly turnover from communities, explained elevation. provide straightforward way biodiversity across large spatial extents without need priori observations. commonly framed potential tool monitoring, show can be applied more widely assess thereby helping advance our understanding biogeographical communities.

Language: Английский

Citations

3
Mapping diversity: from ecology and human geography to urbanism and culture DOI Creative Commons
Dan Costa Baciu, Duola Mi, Callum Birchall

et al.

SN Social Sciences, Journal Year: 2022, Volume and Issue: 2(8)

Published: July 25, 2022

Abstract A large body of research across science and humanities has come to deal with diversity, which, as a scientific concept, proved immensely relevant in helping researchers understand anything from ecosystems natural habitats cities culture. Here, we develop first method quantify map urban diversity. Our article begins concrete example through which demonstrate how apply basic version our create diversity for given area. This is easy interpret can be used accurately locate the most diverse centers activity. We then go on show expanded many different types it regional global maps. Such maps are both studying modeling dynamics diversification environments. conclude by making bridge other disciplines, proposing six key steps that may serve foundation general framework evaluation mapping all fields science.

Language: Английский

Citations

14
Spanning scales: The airborne spatial and temporal sampling design of the National Ecological Observatory Network DOI Creative Commons
John Musinsky, Tristan Goulden, Gregory D. Wirth

et al.

Methods in Ecology and Evolution, Journal Year: 2022, Volume and Issue: 13(9), P. 1866 - 1884

Published: July 28, 2022

Abstract 1. Each year, the National Ecological Observatory Network's (NEON) Airborne Observation Platform (AOP) collects high‐resolution hyperspectral imagery, discrete and waveform lidar, digital photography at a subset of 81 terrestrial aquatic research sites throughout United States. These open remote sensing data, together with NEON in situ sensor measurements field observations, enable researchers to characterize ecological processes multiple spatial temporal scales. 2. Here we describe sampling design for AOP that aims meet diverse needs science community within operational constraints affecting airborne data collection. Our protocol captures instrumented systems, plots environmental gradients around each site while considering context airspace restrictions instrument capabilities. We use time series moderate resolution imaging spectroradiometer (MODIS) satellite PhenoCam near‐surface observations define windows based on vegetation peak foliar greenness. developed probabilistic model MODIS reflectance imagery Monte Carlo simulation estimate durations cloud‐free collection site. 3. Agreement estimated phenophase transition dates between Enhanced Vegetation Index Green Chromatic Coordinate varied by class. Results from both sensors show some classes have relatively consistent interannual greenness start‐ end‐dates, others experience high year‐to‐year variability green‐up senescence. In addition phenological among sites, certain forms demonstrate distinct, asynchronous responses climate, resulting non‐overlapping periods single flight campaigns showed cloud‐likelihood underestimated actual cloud conditions 13%–26%, depending probability used. 4. Where or intra‐site phenology is highly variable clouds are persistent problem, it becomes challenging schedule domain deployments so all flown their communities Despite limitations, application models results significant improvements quality. Although most applicable lidar instruments piloted aircraft, these methods may be valuable resource deployment Unmanned Aerial Vehicles research.

Language: Английский

Citations

14
Individual tree-based vs pixel-based approaches to mapping forest functional traits and diversity by remote sensing DOI
Zhaoju Zheng, Yuan Zeng, Meredith C. Schuman

et al.

International Journal of Applied Earth Observation and Geoinformation, Journal Year: 2022, Volume and Issue: 114, P. 103074 - 103074

Published: Oct. 27, 2022

Language: Английский

Citations

14
Remote sensing of subtropical tree diversity: The underappreciated roles of the practical definition of forest canopy and phenological variation DOI Creative Commons
Yongchao Liu, Ruyun Zhang, Chen‐Feng Lin

et al.

Forest Ecosystems, Journal Year: 2023, Volume and Issue: 10, P. 100122 - 100122

Published: Jan. 1, 2023

Tree species diversity is vital for maintaining ecosystem functions, yet our ability to map the distribution of tree limited due difficulties in traditional field-based approaches. Recent developments spaceborne remote sensing provide unprecedented opportunities and monitor more efficiently. Here we built partial least squares regression models using multispectral surface reflectance acquired by Sentinel-2 satellites inventory data from 74 subtropical forest plots predict canopy a national natural reserve eastern China. In particular, evaluated underappreciated roles practical definition phenological variation predicting testing three different definitions trees comparing satellite imagery seasons. Our best explained 42%–63% variations observed diversities cross-validation tests, with higher explanation power indices that are sensitive abundant species. The imageries early spring late autumn showed consistently better fits than those other seasons, highlighting significant role transitional phenology remotely plant diversity. results suggested cumulative diameter (60%–80%) biggest way define layer subjective fixed-diameter-threshold (5–12 ​cm) or basal area (90%–95%) trees. Remarkably, these approaches resulted contrasting maps call attention structure This study demonstrates potential mapping monitoring Sentinal-2 species-rich forests.

Language: Английский

Citations

8