Monitoring the Vertical Variations in Chlorophyll-a Concentration in Lake Chaohu Using the Geostationary Ocean Color Imager DOI Creative Commons
Hanhan Li,

Xiaoqi Wei,

Zehui Huang

et al.

Remote Sensing, Journal Year: 2024, Volume and Issue: 16(14), P. 2611 - 2611

Published: July 17, 2024

Due to the external environment and buoyancy of cyanobacteria, inhomogeneous vertical distribution phytoplankton in eutrophic lakes affects remote sensing reflectance (Rrs) inversion surface chlorophyll-a concentration (Chla). In this study, profiles Chla(z) (where z is water depth) field Rrs (Rrs_F) were collected utilized retrieve Chla Lake Chaohu China. was categorized into vertically uniform (Type 1: N = 166) non-uniform 2: 58) types. Based on validation atmospheric correction performance Geostationary Ocean Color Imager (GOCI), a model developed for from 2011 2020 using GOCI data (Rrs_G). (1) Five functions compared, best result found × exp(b z) + c (R2 0.98, RMSE 38.15 μg/L). (2) A decision tree established with alternative floating algae index (AFAIRrs), fluorescence line height (FLH), wind speed (WIN), where overall accuracy 89% Kappa coefficient 0.79. The Type 1 empirical relationship between (z surface) AFAIRrs 0.58, 10.17 For 2, multivariate regression models estimate structural parameters combined Rrs_G environmental 0.75, 72.80 (3) There are obvious spatial variations Chla(z), especially depth 0.1 m; largest diurnal observed at 12:16 13:16 local time. method can determine different layers each pixel, which important scientific assessment biomass lake carbon provide information short-term prediction algal blooms (and generation corresponding warnings) management.

Language: Английский

Water–Ecological Health Assessment Considering Water Supply–Demand Balance and Water Supply Security: A Case Study in Xinjiang DOI Creative Commons
Ji Zhang,

Xiaoying Lai,

Aihua Long

et al.

Remote Sensing, Journal Year: 2024, Volume and Issue: 16(20), P. 3834 - 3834

Published: Oct. 15, 2024

Water scarcity and ecological degradation in arid zones present significant challenges to regional health. Despite this, integrating the water supply–demand balance supply security (SEC) into health assessments—particularly through composite indicators—remains underexplored regions. In this study, we assessed changes Xinjiang by utilizing multivariate remote sensing data, focusing on between demand, degree of SEC, ecosystem resilience (ER). Our results indicate that while demand remained relatively stable northern 2000 2020, conflict intensified southern eastern agricultural SEC evaluations revealed 73.3% region experienced varying degrees decline over 20-year period. Additionally, ER assessments showed 7.12% exhibited a decline, with 78.6% experiencing overall reductions The indicators’ response drought demonstrated improvements during wet conditions were less pronounced than declines droughts. This study underscores necessity prioritizing areas lower future allocation strategies optimize resource utilization.

Language: Английский

Citations

1
Hydrogeochemical Insights into the Sustainable Prospects of Groundwater Resources in an Alpine Irrigation Area on Tibetan Plateau DOI Open Access

Shaokang Yang,

Zhen Zhao, Shengbin Wang

et al.

Sustainability, Journal Year: 2024, Volume and Issue: 16(21), P. 9229 - 9229

Published: Oct. 24, 2024

The Tibetan Plateau is the “Asia Water Tower” and pivotal for Asia whole world. Groundwater essential sustainable development in its alpine regions, yet chemical quality increasingly limits usability. present research examines hydrochemical characteristics origins of phreatic groundwater irrigation areas. study probes signatures, quality, regulatory mechanisms a representative area Plateau. findings indicate that maintains slightly alkaline fresh status, with pH values ranging from 7.07 to 8.06 Total Dissolved Solids (TDS) between 300.25 638.38 mg/L. composition mainly HCO3-Ca type, minority HCO3-Na·Ca types, closely mirroring profile river water. Nitrogen contaminants, including NO3−, NO2−, NH4+, exhibit considerable concentration fluctuations within aquifer. Approximately 9.09% sampled groundwaters exceed NO2− threshold 0.02 mg/L, 28.57% surpass NH4+ limit 0.2 mg/L potable water standards. All are below permissible NO3− (50 mg/L). Phreatic exhibits relatively good potability, as assessed by entropy-weighted index (EWQI), 95.24% having an EWQI value 100. However, potential health risks associated elevated levels, rather than merit attention when such consumed minors at certain sporadic sampling locations. does not sodium hazards or soil permeability damage, salinity require attention. makeup primarily dictated rock–water interactions, silicate weathering cation exchange reactions, occasional influences dissolution evaporites carbonates, well reverse cation-exchange processes. While agricultural activities have caused notable rise salinity, they main contributors nitrogen pollution area’s groundwater. Agricultural-derived pollutants vigilant monitoring avert extensive deterioration ensure management resources

Language: Английский

Citations

1
Nonnegligible role of small lakes in global surface water storage dynamics DOI
Nan Xu

Science Bulletin, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 1, 2024

Language: Английский

Citations

1
Editorial for Special Issue: “Monitoring Terrestrial Water Resource Using Multiple Satellite Sensors” DOI Creative Commons
Nan Xu, Yue Ma, Song Li

et al.

Remote Sensing, Journal Year: 2024, Volume and Issue: 16(11), P. 1821 - 1821

Published: May 21, 2024

In the past few decades, with advent of climate change, population growth, agricultural irrigation, and industrial development, there have been increasing demands for water resources across globe, especially in widely distributed arid areas or densely populated [...]

Language: Английский

Citations

0
Monitoring the Vertical Variations in Chlorophyll-a Concentration in Lake Chaohu Using the Geostationary Ocean Color Imager DOI Creative Commons
Hanhan Li,

Xiaoqi Wei,

Zehui Huang

et al.

Remote Sensing, Journal Year: 2024, Volume and Issue: 16(14), P. 2611 - 2611

Published: July 17, 2024

Due to the external environment and buoyancy of cyanobacteria, inhomogeneous vertical distribution phytoplankton in eutrophic lakes affects remote sensing reflectance (Rrs) inversion surface chlorophyll-a concentration (Chla). In this study, profiles Chla(z) (where z is water depth) field Rrs (Rrs_F) were collected utilized retrieve Chla Lake Chaohu China. was categorized into vertically uniform (Type 1: N = 166) non-uniform 2: 58) types. Based on validation atmospheric correction performance Geostationary Ocean Color Imager (GOCI), a model developed for from 2011 2020 using GOCI data (Rrs_G). (1) Five functions compared, best result found × exp(b z) + c (R2 0.98, RMSE 38.15 μg/L). (2) A decision tree established with alternative floating algae index (AFAIRrs), fluorescence line height (FLH), wind speed (WIN), where overall accuracy 89% Kappa coefficient 0.79. The Type 1 empirical relationship between (z surface) AFAIRrs 0.58, 10.17 For 2, multivariate regression models estimate structural parameters combined Rrs_G environmental 0.75, 72.80 (3) There are obvious spatial variations Chla(z), especially depth 0.1 m; largest diurnal observed at 12:16 13:16 local time. method can determine different layers each pixel, which important scientific assessment biomass lake carbon provide information short-term prediction algal blooms (and generation corresponding warnings) management.

Language: Английский

Citations

0