1
|
Wang C, Hu X, Hu K, Liu S, Zhong W. Impact Assessment of the M s7.0 Earthquake on Jiuzhaigou Valley from the Perspective of Vegetation Net Primary Productivity. SENSORS (BASEL, SWITZERLAND) 2022; 22:8875. [PMID: 36433472 PMCID: PMC9693107 DOI: 10.3390/s22228875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/01/2022] [Accepted: 11/15/2022] [Indexed: 06/16/2023]
Abstract
In order to assess the impact of the Ms7.0 Jiuzhaigou earthquake that occurred on 8 August 2017 on vegetation, the Carnegie-Ames-Stanford Approach (CASA) model was adopted to estimate the vegetation net primary productivity (NPP) of Jiuzhaigou Valley, one of the World Heritage Sites, in July, August and September from 2015 to 2019. Then the characteristics of the impact of different earthquake-induced geohazards on vegetation were discussed, and a vulnerability-resilience assessment system concerning the seismic intensity was proposed. The results show that the NPPmax and NPPmean values in Jiuzhaigou Valley first decreased and then increased and were 151.5-261.9 gC/m2 and 54.6-116.3 gC/m2, respectively. The NPP value of more than 70% area was 90-150 gC/m2 in July. In August, the NPPmean values decreased, and the areas with lower values became larger; the NPPmean values of most areas affected by geohazards were 60-150 gC/m2. During the earthquake, the NPPmean values of areas hit by geohazards sharply declined by 27.2% (landslide), 22.4% (debris flow) and 15.7% (collapse) compared with those in the same month in 2016. Vegetation in debris flow zones showed a stronger recovery, with a maximum NPP value increase of about 23.0% in September 2017. The vegetation gradually recovered after the earthquake, as indicated by the uptrend of the NPP values in the corresponding period in 2018 and 2019. In general, the reduction magnitude of NPP values decreased year by year in comparison to that in 2015 and 2016, and the decrease slowed down after the earthquake. The vulnerability and resilience index corresponding to the three seismic intensity ranges were 0.470-0.669 and 0.642-0.693, respectively, and those of Jiuzhaigou Valley were 0.473 and 0.671, respectively. The impact coefficient defined to represent the impact of the earthquake on NPP was 0.146-0.213. This paper provides a theoretical reference and guidance for the impact assessment of earthquakes on the ecosystem.
Collapse
Affiliation(s)
- Chenyuan Wang
- Hubei Key Laboratory of Disaster Prevention and Mitigation, College of Civil Engineering and Architecture, China Three Gorges University, Yichang 443002, China
- College of Civil Engineering and Architecture, China Three Gorges University, Yichang 443002, China
| | - Xudong Hu
- Hubei Key Laboratory of Disaster Prevention and Mitigation, College of Civil Engineering and Architecture, China Three Gorges University, Yichang 443002, China
- College of Civil Engineering and Architecture, China Three Gorges University, Yichang 443002, China
| | - Kaiheng Hu
- Key Laboratory of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences, Chengdu 610041, China
- Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
| | - Shuang Liu
- Key Laboratory of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences, Chengdu 610041, China
- Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
| | - Wei Zhong
- Key Laboratory of Mountain Hazards and Earth Surface Processes, Chinese Academy of Sciences, Chengdu 610041, China
- Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
| |
Collapse
|
2
|
Tao F, Zhou Z, Huang Y, Li Q, Lu X, Ma S, Huang X, Liang Y, Hugelius G, Jiang L, Doughty R, Ren Z, Luo Y. Deep Learning Optimizes Data-Driven Representation of Soil Organic Carbon in Earth System Model Over the Conterminous United States. Front Big Data 2020; 3:17. [PMID: 33693391 PMCID: PMC7931903 DOI: 10.3389/fdata.2020.00017] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 04/21/2020] [Indexed: 11/13/2022] Open
Abstract
Soil organic carbon (SOC) is a key component of the global carbon cycle, yet it is not well-represented in Earth system models to accurately predict global carbon dynamics in response to climate change. This novel study integrated deep learning, data assimilation, 25,444 vertical soil profiles, and the Community Land Model version 5 (CLM5) to optimize the model representation of SOC over the conterminous United States. We firstly constrained parameters in CLM5 using observations of vertical profiles of SOC in both a batch mode (using all individual soil layers in one batch) and at individual sites (site-by-site). The estimated parameter values from the site-by-site data assimilation were then either randomly sampled (random-sampling) to generate continentally homogeneous (constant) parameter values or maximally preserved for their spatially heterogeneous distributions (varying parameter values to match the spatial patterns from the site-by-site data assimilation) so as to optimize spatial representation of SOC in CLM5 through a deep learning technique (neural networking) over the conterminous United States. Comparing modeled spatial distributions of SOC by CLM5 to observations yielded increasing predictive accuracy from default CLM5 settings (R 2 = 0.32) to randomly sampled (0.36), one-batch estimated (0.43), and deep learning optimized (0.62) parameter values. While CLM5 with parameter values derived from random-sampling and one-batch methods substantially corrected the overestimated SOC storage by that with default model parameters, there were still considerable geographical biases. CLM5 with the spatially heterogeneous parameter values optimized from the neural networking method had the least estimation error and less geographical biases across the conterminous United States. Our study indicated that deep learning in combination with data assimilation can significantly improve the representation of SOC by complex land biogeochemical models.
Collapse
Affiliation(s)
- Feng Tao
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China.,National Supercomputing Center in Wuxi, Wuxi, China
| | - Zhenghu Zhou
- Center for Ecological Research, Northeast Forestry University, Harbin, China
| | - Yuanyuan Huang
- Le Laboratoire des Sciences du Climat et de l'Environnement, IPSL-LSCECEA/CNRS/UVSQ Saclay, Gif-sur-Yvette, France
| | - Qianyu Li
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China.,National Supercomputing Center in Wuxi, Wuxi, China
| | - Xingjie Lu
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, China.,Department of Biological Sciences, Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, United States
| | - Shuang Ma
- Department of Biological Sciences, Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, United States
| | - Xiaomeng Huang
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China.,National Supercomputing Center in Wuxi, Wuxi, China
| | - Yishuang Liang
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China.,National Supercomputing Center in Wuxi, Wuxi, China
| | - Gustaf Hugelius
- Department of Physical Geography and Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
| | - Lifen Jiang
- Department of Biological Sciences, Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, United States
| | - Russell Doughty
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, United States
| | - Zhehao Ren
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China
| | - Yiqi Luo
- Department of Biological Sciences, Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, United States
| |
Collapse
|
4
|
Forkel M, Drüke M, Thurner M, Dorigo W, Schaphoff S, Thonicke K, von Bloh W, Carvalhais N. Constraining modelled global vegetation dynamics and carbon turnover using multiple satellite observations. Sci Rep 2019; 9:18757. [PMID: 31822728 PMCID: PMC6904745 DOI: 10.1038/s41598-019-55187-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 11/25/2019] [Indexed: 12/02/2022] Open
Abstract
The response of land ecosystems to future climate change is among the largest unknowns in the global climate-carbon cycle feedback. This uncertainty originates from how dynamic global vegetation models (DGVMs) simulate climate impacts on changes in vegetation distribution, productivity, biomass allocation, and carbon turnover. The present-day availability of a multitude of satellite observations can potentially help to constrain DGVM simulations within model-data integration frameworks. Here, we use satellite-derived datasets of the fraction of absorbed photosynthetic active radiation (FAPAR), sun-induced fluorescence (SIF), above-ground biomass of trees (AGB), land cover, and burned area to constrain parameters for phenology, productivity, and vegetation dynamics in the LPJmL4 DGVM. Both the prior and the optimized model accurately reproduce present-day estimates of the land carbon cycle and of temporal dynamics in FAPAR, SIF and gross primary production. However, the optimized model reproduces better the observed spatial patterns of biomass, tree cover, and regional forest carbon turnover. Using a machine learning approach, we found that remaining errors in simulated forest carbon turnover can be explained with bioclimatic variables. This demonstrates the need to improve model formulations for climate effects on vegetation turnover and mortality despite the apparent successful constraint of simulated vegetation dynamics with multiple satellite observations.
Collapse
Affiliation(s)
- Matthias Forkel
- Technische Universität Dresden, Institute of Photogrammetry and Remote Sensing, Helmholtzstr. 10, 01069, Dresden, Germany.
| | - Markus Drüke
- Potsdam Institute for Climate Impact Research, Telegraphenberg A 62, Potsdam, Germany
| | - Martin Thurner
- Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325, Frankfurt am Main, Germany
| | - Wouter Dorigo
- TU Wien, Department of Geodesy and Geoinformation, Gusshausstr. 27-29, Vienna, Austria
| | - Sibyll Schaphoff
- Potsdam Institute for Climate Impact Research, Telegraphenberg A 62, Potsdam, Germany
| | - Kirsten Thonicke
- Potsdam Institute for Climate Impact Research, Telegraphenberg A 62, Potsdam, Germany
| | - Werner von Bloh
- Potsdam Institute for Climate Impact Research, Telegraphenberg A 62, Potsdam, Germany
| | - Nuno Carvalhais
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, Jena, Germany
| |
Collapse
|