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Han J, Kim M, Mammadov Z, Lee S, Elzinga EJ, Mammadov G, Hwang W, Ro HM. Synergistic effect of climate change and water management: Historical and future soil salinity in the Kur-Araz lowland, Azerbaijan. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167720. [PMID: 37827308 DOI: 10.1016/j.scitotenv.2023.167720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 10/05/2023] [Accepted: 10/08/2023] [Indexed: 10/14/2023]
Abstract
While soil salinization is a major threat to the food security and sustainability of humanity, information on salinization in developing countries is limited. In this study, Landsat data were used to predict the salinization process from 1986 to 2021 in the Kur-Araz lowland of Azerbaijan, and water movement and salinity transport models were developed to calculate the effects of climate change and water management. The model results showed that increases in rainfall and drainage have led to dramatic improvements in soil salinity and agricultural productivity and that these changes were caused by the synergistic effect of climate change and water management. The future predictions indicate that rainfall will decrease due to the decrease in evaporation in the neighboring Caspian Sea, leading to further re-salinization. Soil re-salinization would be a severe threat to the sustainability of the agricultural industry and food security of Azerbaijan and neighboring countries. More scientific attention and efforts should be devoted to developing countries in preparation for the impact of climate change.
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Affiliation(s)
- Junho Han
- Institute of Life Science and Natural Resources, Korea University, Seoul, 02841, Republic of Korea; Department of Earth and Environmental Sciences, Rutgers University, Newark, NJ 07102, United States.
| | - Minhee Kim
- Ministry of Environment, 229 Misagangbyeonhangang-ro, Hanam-si, Gyeonggi-do 12902, Republic of Korea.
| | - Zaman Mammadov
- Institute of Soil Science and Agrochemistry, Azerbaijan National Academy of Sciences, Baku AZ10073, Azerbaijan.
| | - Seoyeon Lee
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea.
| | - Evert J Elzinga
- Department of Earth and Environmental Sciences, Rutgers University, Newark, NJ 07102, United States.
| | - Garib Mammadov
- Institute of Soil Science and Agrochemistry, Azerbaijan National Academy of Sciences, Baku AZ10073, Azerbaijan.
| | - Wonjae Hwang
- Department of Environmental and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
| | - Hee-Myong Ro
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea.
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Noori R, Maghrebi M, Jessen S, Bateni SM, Heggy E, Javadi S, Noury M, Pistre S, Abolfathi S, AghaKouchak A. Decline in Iran's groundwater recharge. Nat Commun 2023; 14:6674. [PMID: 37865681 PMCID: PMC10590393 DOI: 10.1038/s41467-023-42411-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 10/11/2023] [Indexed: 10/23/2023] Open
Abstract
Groundwater recharge feeds aquifers supplying fresh-water to a population over 80 million in Iran-a global hotspot for groundwater depletion. Using an extended database comprising abstractions from over one million groundwater wells, springs, and qanats, from 2002 to 2017, here we show a significant decline of around -3.8 mm/yr in the nationwide groundwater recharge. This decline is primarily attributed to unsustainable water and environmental resources management, exacerbated by decadal changes in climatic conditions. However, it is important to note that the former's contribution outweighs the latter. Our results show the average annual amount of nationwide groundwater recharge (i.e., ~40 mm/yr) is more than the reported average annual runoff in Iran (i.e., ~32 mm/yr), suggesting the surface water is the main contributor to groundwater recharge. Such a decline in groundwater recharge could further exacerbate the already dire aquifer depletion situation in Iran, with devastating consequences for the country's natural environment and socio-economic development.
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Affiliation(s)
- Roohollah Noori
- Graduate Faculty of Environment, University of Tehran, Tehran, Iran.
- Faculty of Governance, University of Tehran, Tehran, Iran.
| | - Mohsen Maghrebi
- Graduate Faculty of Environment, University of Tehran, Tehran, Iran
| | - Søren Jessen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - Sayed M Bateni
- Department of Civil and Environmental Engineering and Water Resources Research Center, University of Hawaii at Manoa, Honolulu, HI, USA
| | - Essam Heggy
- Viterbi School of Engineering, University of Southern California, Los Angeles, CA, USA
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Saman Javadi
- Department of Water Engineering, College of Abouraihan, University of Tehran, Tehran, Iran
| | - Mojtaba Noury
- Iran Water Resources Management Company, Ministry of Energy, Tehran, Iran
| | - Severin Pistre
- HydroSciences Montpellier, University of Montpellier, CNRS, IRD, Montpellier, France
| | | | - Amir AghaKouchak
- Department of Civil and Environmental Engineering, University of California, Irvine, USA
- Department of Earth System Science, University of California, Irvine, USA
- Institute for Water, Environment and Health, United Nations University, Hamilton, ON, Canada
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Amiri V, Ali S, Sohrabi N, Amiri F. Hydrogeochemical evaluation with emphasis on nitrate and fluoride in urban and rural drinking water resources in western Isfahan province, central Iran. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:108720-108740. [PMID: 37752392 DOI: 10.1007/s11356-023-30001-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 09/17/2023] [Indexed: 09/28/2023]
Abstract
Nitrate (NO3-) and fluoride (F-) are two major potential contaminants found in the groundwater of Iran. These contaminants are highly dangerous to humans if consumed more than the safe limit prescribed by the WHO. Therefore, in this study, the urban and rural drinking water resources of Isfahan province (central Iran) were investigated to evaluate the quality of groundwater from the perspective of NO3- and F-. The calculated saturation index (SI) shows that the majority of samples are mainly undersaturated or in equilibrium with respect to potential minerals. The most likely interpretation for undersaturation with respect to most minerals is either that the minerals are not present if they are reactive or if they are present, then they are not reactive. This study reveals that the majority of the groundwater samples belong to the Ca-Mg-HCO3 water type. Further, in this study, potential physicochemical variables have been used to calculate entropy weighted water quality index (EWQI). The EWQI reveals that the majority of the groundwater in the area is of good quality. Results show that the water chemistry in the area is largely governed by the water-rock interaction. This study based on large data sets reveals that the majority of drinking water resources are uncontaminated by F-. However, the groundwater is found to be largely contaminated by NO3-. The bivariate plot suggests that the unscientific farming practices and overuse of manures and fertilizers are largely responsible for high content of NO3-. Therefore, emphasis should be given on the cost-effective environmentally friendly fertilizers. The findings from this study will aid the governing authorities and concerned stakeholders to understand the hydrogeochemical evolution of groundwater in this region. The results will help formulate policies in the area for sustainable water supply.
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Affiliation(s)
- Vahab Amiri
- Department of Geology, Yazd University, Yazd, Iran.
| | - Shakir Ali
- CAWTM, MRIIRS, Sector - 43, Faridabad, Haryana, 121004, India
| | | | - Fahimeh Amiri
- Water & Wastewater Company of Isfahan, Isfahan, Iran
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Meng Q, Yan C, Li R, Zhang T, Zheng M, Liu Y, Zhang M, Wang G, Du Y, Shang C, Fu P. Variations of PM 2.5-bound elements and their associated effects during long-distance transport of dust storms: Insights from multi-sites observations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 889:164062. [PMID: 37207767 DOI: 10.1016/j.scitotenv.2023.164062] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/24/2023] [Accepted: 05/07/2023] [Indexed: 05/21/2023]
Abstract
Dust storms are a significant concern because of their adverse effects on ambient air quality and human health. To investigate the evolution of dust storms during long-distance transport and its impacts on air quality and human health risks in cities along the transport pathway, we monitored the major fraction of dust (i.e., particle-bound elements) online in four cities in northern China during March 2021. Three dust events originating from the Gobi Desert of North China and Mongolia and the Taklimakan Desert of Northwest China were captured. We investigated the source regions of dust storms using daily multi-sensor absorbing aerosol index products, backward trajectories, and specific element ratios, identified and quantified sources of particle-bound elements using Positive Matrix Factorization model, and calculated the carcinogenic and non-carcinogenic risks of elements using a health risk assessment model. Our results indicated that under the influence of dust storms, mass concentrations of crustal elements increased up to dozens of times in cities near the dust source and up to ten times in cities farther from the source. In contrast, anthropogenic elements increased less or even decreased, depending on the relative contributions of the increase caused by accumulation of dust itself and entrainment along the transport path and the decrease caused by dilution of high wind speeds. Si/Fe ratio was found to be a valuable indicator for characterizing the attenuation of the amount of dust along its transport pathways, especially for the case originated from northern source regions. This study highlights the significant role of source regions, intensity and attenuation rates of dust storms, and wind speeds in determining the increased levels of element concentrations during dust storms and its associated impacts on downwind areas. Furthermore, non-carcinogenic risks of particle-bound elements increased at all sites during dust events, emphasizing the importance of personal exposure protection during dust storms.
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Affiliation(s)
- Qingpeng Meng
- Environment Research Institute, Shandong University, Qingdao 266237, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 511443, China
| | - Caiqing Yan
- Environment Research Institute, Shandong University, Qingdao 266237, China.
| | - Ruiyu Li
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Tianle Zhang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Mei Zheng
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yue Liu
- Center for Environmental Metrology, National Institute of Metrology China, Beijing 100029, China
| | - Miao Zhang
- Shandong Provincial Eco-Environment Monitoring, Jinan 250101, China
| | - Guixia Wang
- Shandong Provincial Eco-Environment Monitoring, Jinan 250101, China
| | - Yuming Du
- Wuhai Environmental Monitoring Center Station, Inner Mongolia 01600, China
| | - Chunlin Shang
- Wuhai Environmental Monitoring Center Station, Inner Mongolia 01600, China
| | - Peng Fu
- Sailhero Environmental Protection High-tech Co., Ltd, Shijiazhuang 050035, China
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Mehmandar MN, Rasouli F, Giglou MT, Zahedi SM, Hassanpouraghdam MB, Aazami MA, Tajaragh RP, Ryant P, Mlcek J. Polyethylene Glycol and Sorbitol-Mediated In Vitro Screening for Drought Stress as an Efficient and Rapid Tool to Reach the Tolerant Cucumis melo L. Genotypes. PLANTS (BASEL, SWITZERLAND) 2023; 12:870. [PMID: 36840218 PMCID: PMC9967323 DOI: 10.3390/plants12040870] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/09/2022] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
An efficient method to instantly assess drought-tolerant plants after germination is using osmoregulation in tissue culture media. In this study, the responses of three Iranian melon genotypes to sorbitol (0.1, 0.2, and 0.4 M) or polyethylene glycol (PEG) (0.009, 0.012, and 0.015 M) were evaluated as drought stress simulators in MS medium. 'Girke' (GIR), 'Ghobadloo' (GHO), and 'Toghermezi' (TOG) were the genotypes. GIR is reputed as a drought-tolerant genotype in Iran. The PEG or sorbitol decreased the coleoptile length, fresh weight, and photosynthetic pigments content while enhancing proline and malondialdehyde (MDA) contents. Protein content and antioxidant enzyme activity were utterly dependent on genotype, osmotic regulators, and their concentration. Coleoptile length, root and shoot fresh weight, root dry weight, proline and MDA content, and guaiacol peroxidase (GPX) activity can be used as indicators for in vitro screening of Cucumis melo L. genotypes. The results showed that sorbitol mimics drought stress better than PEG. Overall, our findings suggest that in vitro screening could be an accurate, rapid, and reliable methodology for evaluating and identifying drought-tolerant genotypes.
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Affiliation(s)
- Maryam Nekoee Mehmandar
- Department of Horticulture, Faculty of Agriculture, University of Maragheh, Maragheh 5518779842, Iran
| | - Farzad Rasouli
- Department of Horticulture, Faculty of Agriculture, University of Maragheh, Maragheh 5518779842, Iran
| | - Mousa Torabi Giglou
- Department of Horticulture, Faculty of Agriculture, University of Mohaghegh Ardabili, Ardabil 5619911367, Iran
| | - Seyed Morteza Zahedi
- Department of Horticulture, Faculty of Agriculture, University of Maragheh, Maragheh 5518779842, Iran
| | | | - Mohammad Ali Aazami
- Department of Horticulture, Faculty of Agriculture, University of Maragheh, Maragheh 5518779842, Iran
| | - Rana Panahi Tajaragh
- Department of Horticulture, Faculty of Agriculture, University of Maragheh, Maragheh 5518779842, Iran
| | - Pavel Ryant
- Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriScience, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic
| | - Jiri Mlcek
- Department of Food Analysis and Chemistry, Faculty of Technology, Tomas Bata University in Zlin, Vavreckova 5669, 760 01 Zlin, Czech Republic
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Mirzaei M, Gorji Anari M, Saronjic N, Sarkar S, Kral I, Gronauer A, Mohammed S, Caballero-Calvo A. Environmental impacts of corn silage production: influence of wheat residues under contrasting tillage management types. ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 195:171. [PMID: 36459271 PMCID: PMC9718881 DOI: 10.1007/s10661-022-10675-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 10/19/2022] [Indexed: 06/17/2023]
Abstract
The intensification of specific land management operations (tillage, herbicide, etc.) is increasing land degradation and contributing to ecosystem pollution. Mulches can be a sustainable tool to counter these processes. This is particularly relevant for rural areas in low-income countries where agriculture is a vital sector. In this research, the environmental impact of different rates of wheat residues (no residues, 25, 50, 75, and 100%) in corn silage cultivation was evaluated using the life cycle assessment (LCA) method under conventional tillage (CT) and no-tillage (NT) systems in a semi-arid region in Karaj, Iran. Results showed that in both tillage systems, marine aquatic ecotoxicity (ME) and global warming potential (GWP) had the highest levels of pollution among the environmental impact indicators. In CT systems, the minimum (17,730.70 kg 1,4-dichlorobenzene (DB) eq.) and maximum (33,683.97 kg 1,4-DB eq.) amounts of ME were related to 0 and 100% wheat residue rates, respectively. Also, in the CT system, 0 and 100% wheat residue rates resulted in minimum (176.72 kg CO2 eq.) and maximum (324.95 kg CO2 eq.) amounts of GWP, respectively. However, in the NT system, the 100% wheat residue rate showed the minimum amounts of ME (11,442.39 kg 1,4-DB eq.) and GWP (120.21 kg CO2 eq.). Also, in the NT system, maximum amounts of ME (17,174 kg 1,4-DB eq.) and GWP (175.60 kg CO2 eq.) were observed with a zero wheat residue rate. On-farm emissions and nitrogen fertilizers were the two factors with the highest contribution to the degradation related to environmental parameters at all rates of wheat residues. Moreover, in the CT system, the number of environmental pollutants increased with the addition of a higher wheat residue rate, while in the NT system, increasing residue rates decreased the amount of environmental pollutants. In conclusion, this LCA demonstrates that the NT system with the full retention of wheat residues (100%) is a more environmentally sustainable practice for corn silage production. Therefore, it may be considered one of the most adequate management strategies in this region and similar semi-arid conditions. Further long-term research and considering more environmental impact categories are required to assess the real potential of crop residues and tillage management for sustainable corn silage production.
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Affiliation(s)
- Morad Mirzaei
- Department of Soil Science and Engineering, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran.
| | - Manouchehr Gorji Anari
- Department of Soil Science and Engineering, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran
| | - Nermina Saronjic
- Institute of Soil Research, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
| | - Sudip Sarkar
- ICAR Research Complex for Eastern Region, Patna, 800014, India
| | - Iris Kral
- Institute of Agricultural Engineering, Department of Sustainable Agricultural Systems, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Andreas Gronauer
- Institute of Agricultural Engineering, Department of Sustainable Agricultural Systems, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Safwan Mohammed
- Institute of Land Utilization, Technology and Regional Planning, Faculty of Agricultural and Food Sciences and Environmental Management, University of Debrecen, Debrecen, Hungary
| | - Andrés Caballero-Calvo
- Departamento de Análisis Geográfico Regional y Geografía Física, Facultad de Filosofía y Letras, Universidad de Granada, Campus Universitario de Cartuja, 18071, Granada, Spain.
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Behling R, Roessner S, Foerster S, Saemian P, Tourian MJ, Portele TC, Lorenz C. Interrelations of vegetation growth and water scarcity in Iran revealed by satellite time series. Sci Rep 2022; 12:20784. [PMID: 36456635 PMCID: PMC9715656 DOI: 10.1038/s41598-022-24712-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 11/18/2022] [Indexed: 12/03/2022] Open
Abstract
Iran has experienced a drastic increase in water scarcity in the last decades. The main driver has been the substantial unsustainable water consumption of the agricultural sector. This study quantifies the spatiotemporal dynamics of Iran's hydrometeorological water availability, land cover, and vegetation growth and evaluates their interrelations with a special focus on agricultural vegetation developments. It analyzes globally available reanalysis climate data and satellite time series data and products, allowing a country-wide investigation of recent 20+ years at detailed spatial and temporal scales. The results reveal a wide-spread agricultural expansion (27,000 km[Formula: see text]) and a significant cultivation intensification (48,000 km[Formula: see text]). At the same time, we observe a substantial decline in total water storage that is not represented by a decrease of meteorological water input, confirming an unsustainable use of groundwater mainly for agricultural irrigation. As consequence of water scarcity, we identify agricultural areas with a loss or reduction of vegetation growth (10,000 km[Formula: see text]), especially in irrigated agricultural areas under (hyper-)arid conditions. In Iran's natural biomes, the results show declining trends in vegetation growth and land cover degradation from sparse vegetation to barren land in 40,000 km[Formula: see text], mainly along the western plains and foothills of the Zagros Mountains, and at the same time wide-spread greening trends, particularly in regions of higher altitudes. Overall, the findings provide detailed insights in vegetation-related causes and consequences of Iran's anthropogenic drought and can support sustainable management plans for Iran or other semi-arid regions worldwide, often facing similar conditions.
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Affiliation(s)
- Robert Behling
- grid.23731.340000 0000 9195 2461Remote Sensing and Geoinformatics Section, Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Potsdam, Germany
| | - Sigrid Roessner
- grid.23731.340000 0000 9195 2461Remote Sensing and Geoinformatics Section, Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Potsdam, Germany
| | - Saskia Foerster
- grid.23731.340000 0000 9195 2461Remote Sensing and Geoinformatics Section, Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Potsdam, Germany
| | - Peyman Saemian
- grid.5719.a0000 0004 1936 9713Institute of Geodesy, University of Stuttgart, Stuttgart, Germany
| | - Mohammad J. Tourian
- grid.5719.a0000 0004 1936 9713Institute of Geodesy, University of Stuttgart, Stuttgart, Germany
| | - Tanja C. Portele
- grid.7892.40000 0001 0075 5874Karlsruhe Institute of Technology (KIT), Campus Alpin, Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, Germany
| | - Christof Lorenz
- grid.7892.40000 0001 0075 5874Karlsruhe Institute of Technology (KIT), Campus Alpin, Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Garmisch-Partenkirchen, Germany
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Papi R, Kakroodi A, Soleimani M, Karami L, Amiri F, Alavipanah SK. Identifying sand and dust storm sources using spatial-temporal analysis of remote sensing data in Central Iran. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101724] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Linear and Non-Linear Vegetation Trend Analysis throughout Iran Using Two Decades of MODIS NDVI Imagery. REMOTE SENSING 2022. [DOI: 10.3390/rs14153683] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Vegetation is the main component of the terrestrial Earth, and it plays an imperative role in carbon cycle regulation and surface water/energy exchange/balance. The coupled effects of climate change and anthropogenic forcing have undoubtfully impacted the vegetation cover in linear/non-linear manners. Considering the essential benefits of vegetation to the environment, it is vital to investigate the vegetation dynamics through spatially and temporally consistent workflows. In this regard, remote sensing, especially Normalized Difference Vegetation Index (NDVI), has offered a reliable data source for vegetation monitoring and trend analysis. In this paper, two decades (2000 to 2020) of Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI datasets (MOD13Q1) were used for vegetation trend analysis throughout Iran. First, the per-pixel annual NDVI dataset was prepared using the Google Earth Engine (GEE) by averaging all available NDVI values within the growing season and was then fed into the PolyTrend algorithm for linear/non-linear trend identification. In total, nearly 14 million pixels (44% of Iran) were subjected to trend analysis, and the results indicated a higher rate of greening than browning across the country. Regarding the trend types, linear was the dominant trend type with 14%, followed by concealed (11%), cubic (8%), and quadratic (2%), while 9% of the vegetation area remained stable (no trend). Both positive and negative directions were observed in all trend types, with the slope magnitudes ranging between −0.048 and 0.047 (NDVI units) per year. Later, precipitation and land cover datasets were employed to further investigate the vegetation dynamics. The correlation coefficient between precipitation and vegetation (NDVI) was 0.54 based on all corresponding observations (n = 1785). The comparison between vegetation and precipitation trends revealed matched trend directions in 60% of cases, suggesting the potential impact of precipitation dynamics on vegetation covers. Further incorporation of land cover data showed that grassland areas experienced significant dynamics with the highest proportion compared to other vegetation land cover types. Moreover, forest and cropland had the highest positive and negative trend direction proportions. Finally, independent (from trend analysis) sources were used to examine the vegetation dynamics (greening/browning) from other perspectives, confirming Iran’s greening process and agreeing with the trend analysis results. It is believed that the results could support achieving Sustainable Development Goals (SDGs) by serving as an initial stage study for establishing conservation and restoration practices.
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Elnashar A, Zeng H, Wu B, Gebremicael TG, Marie K. Assessment of environmentally sensitive areas to desertification in the Blue Nile Basin driven by the MEDALUS-GEE framework. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 815:152925. [PMID: 34999074 DOI: 10.1016/j.scitotenv.2022.152925] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/31/2021] [Accepted: 01/01/2022] [Indexed: 06/14/2023]
Abstract
Assessing environmentally sensitive areas (ESA) to desertification and understanding their primary drivers are necessary for applying targeted management practices to combat land degradation at the basin scale. We have developed the MEditerranean Desertification And Land Use framework in the Google Earth Engine cloud platform (MEDALUS-GEE) to map and assess the ESA index at 300 m grids in the Blue Nile Basin (BNB). The ESA index was derived from elaborating 19 key indicators representing soil, climate, vegetation, and management through the geometric mean of their sensitivity scores. The results showed that 43.4%, 28.8%, and 70.4% of the entire BNB, Upper BNB, and Lower BNB, respectively, are highly susceptible to desertification, indicating appropriate land and water management measures should be urgently implemented. Our findings also showed that the main land degradation drivers are moderate to intensive cultivation across the BNB, high slope gradient and water erosion in the Upper BNB, and low soil organic matter and vegetation cover in the Lower BNB. The study presented an integrated monitoring and assessment framework for understanding desertification processes to help achieve land-related sustainable development goals.
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Affiliation(s)
- Abdelrazek Elnashar
- State Key Laboratory of Remote Sensing Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Department of Natural Resources, Faculty of African Postgraduate Studies, Cairo University, Giza 12613, Egypt.
| | - Hongwei Zeng
- State Key Laboratory of Remote Sensing Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Bingfang Wu
- State Key Laboratory of Remote Sensing Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Tesfay Gebretsadkan Gebremicael
- Soil and Water Science Department, University of Florida/IFAS/West Florida Research and Education Center, 5988 Hwy 90, Bldg 4900, Milton, FL 32583, USA; Tigray Agricultural Research Institute, Mekelle 492, Ethiopia..
| | - Khadiga Marie
- Department of Geography and Geographic Information Systems, Faculty of African Postgraduate Studies, Cairo University, Giza 12613, Egypt.
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