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Meng X, Chen J, Li Z, Liu Z, Jiang X, Ge Y, Cooper KM, Xie Z. Degraded functional structure of macroinvertebrates caused by commercial sand dredging practices in a flood plain lake. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 263:114415. [PMID: 32229376 DOI: 10.1016/j.envpol.2020.114415] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 06/10/2023]
Abstract
In parts of developing countries, the over-exploitation of sands from inland waters has led to serious environmental concerns. However, understanding of the impacts of commercial sand dredging on inland water ecosystem functions remains limited. Herein, we assess the effects of this activity on the functional structure of the macroinvertebrate community and its recovery processes based on a 4-year survey, in the South Dongting Lake in China. Our result showed a simplified macroinvertebrate functional structures within the dredged area, as evidenced by a loss of certain trait categories (e.g., oval and conical body form) and a significant reduction in trait values due to the direct removal of macroinvertebrates and indirect alternations to physical environmental conditions (e.g., water depth and %Medium sand). Moreover, clear increases were observed in certain trait categories (e.g., small body size and swimmer) resulting from the dredging-related disturbance (e.g., increased turbidity) within the adjacent area. Furthermore, one year after the cessation of dredging, a marked recovery in the taxonomic and functional structure of macroinvertebrate assemblages was observed with most lost trait categories returning and an increase in the trait values of eight categories (e.g., body size 1.00-3.00 cm and oval body form) within the dredged and adjacent area. In addition, dispersal processes and sediment composition were the main driver for the structuring of the macroinvertebrate taxonomic and functional assemblages during the dredging stages, whilst water environmental conditions dominated the taxonomic structure and dispersal processes determined the functional structure during the recovery stage. Implications of our results for monitoring and management of this activity in inland waters are discussed.
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Affiliation(s)
- Xingliang Meng
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei, 430072, China
| | - Juanjuan Chen
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhengfei Li
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei, 430072, China
| | - Zhenyuan Liu
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuankong Jiang
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yihao Ge
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Keith M Cooper
- Centre for Environment, Fisheries and Aquaculture Science, Lowestoft, NR330HT, United Kingdom
| | - Zhicai Xie
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei, 430072, China.
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Long Y, Yan S, Jiang C, Wu C, Tang R, Hu S. Inversion of Lake Bathymetry through Integrating Multi-Temporal Landsat and ICESat Imagery. SENSORS 2019; 19:s19132896. [PMID: 31261991 PMCID: PMC6651279 DOI: 10.3390/s19132896] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 05/25/2019] [Accepted: 06/25/2019] [Indexed: 11/30/2022]
Abstract
Lake bathymetry provides valuable information for lake basin planning and treatment, lake watershed erosion and siltation management, water resource planning, and environmental protection. Lake bathymetry has been surveyed with sounding techniques, including single-beam and multi-beam sonar sounding, and unmanned ship sounding. Although these techniques have high accuracy, most of them require long survey cycles and entail a high degree of difficulty. On the contrary, optical remote sensing inversion methods are easy to implement, but tend to provide less accurate bathymetry measures, especially when applied to turbid waters. The present study, therefore, aims to improve the accuracy of bathymetry measurements through integrating Landsat Thematic Mapper imagery, the Ice, Cloud, and Land Elevation Satellite’s Geoscience Laser Altimeter System (ICESat/GLAS) data, and water level data measured at hydrological stations. First, the boundaries of a lake at multiple dates were derived using water extraction, initial boundary extraction, and Landsat Thematic Mapper/Enhanced Thematic Mapper (TM/ETM+) strip removal processing techniques. Second, ICESat/GLAS data were introduced to obtain additional topographic information of a lake. The striped topography of a lake’s area was then obtained through eliminating and correcting erroneous points and interpolating the values of unknown points. Third, the entire bathymetry of the lake was obtained through interpolating water level values of lake boundary points in various dates. Experiments show that accurate bathymetry (±1 m) can be successfully derived.
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Affiliation(s)
- Yuannan Long
- School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China
- Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha 410114, China
- Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, China
| | - Shixiong Yan
- School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China
| | - Changbo Jiang
- School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China
- Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha 410114, China
- Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, China
| | - Changshan Wu
- Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha 410114, China.
- Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, China.
- Department of Geography, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA.
| | - Rong Tang
- School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China
| | - Shixiong Hu
- School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China
- Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha 410114, China
- Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, China
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Meng X, Jiang X, Li Z, Wang J, Cooper KM, Xie Z. Responses of macroinvertebrates and local environment to short-term commercial sand dredging practices in a flood-plain lake. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 631-632:1350-1359. [PMID: 29727959 DOI: 10.1016/j.scitotenv.2018.03.086] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 03/06/2018] [Accepted: 03/08/2018] [Indexed: 06/08/2023]
Abstract
In parts of the developing world, the expansion of industrial sand mining activities has led to serious environmental concerns. However, current understanding of the effects of this activity on an inland water ecosystem remains limited. Herein, we choose the "most affected" lake in China (Dongting Lake), to assess short-term (1year) effects of sand dredging on key environmental parameters and on the structure of the macroinvertebrate assemblage. Within the dredged area we observed increases in water depth (on average 2.17m), turbidity and changes in sediment composition (e.g., increase in % medium sand, and a decrease in % clay). In addition, dredging was associated with a 50 % reduction in taxa richness, Simpson and Shannon-Wiener indices, and a 72 and 99 % reduction in abundance and biomass, respectively. Indirect effects were also observed in the zone surrounding the extraction sites (ca. 500m), most likely as a result of the dredging processes (e.g., sediment screening and overspill) and water flow. No such effects were observed at a nearby reference site. The direct removal of sediment and indirect alteration of physical conditions (e.g., water depth, turbidity and sediment composition) appear to be the most likely cause of variations in the benthic community. Implications of our findings for the planning, management and monitoring of sand dredging in inland waters are discussed.
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Affiliation(s)
- Xingliang Meng
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoming Jiang
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei 430072, China
| | - Zhengfei Li
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Wang
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Keith M Cooper
- Centre for Environment, Fisheries and Aquaculture Science, Lowestoft NR330HT, United Kingdom
| | - Zhicai Xie
- The Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Hubei 430072, China.
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Stepping-stones and dispersal flow: establishment of a meta-population of Milu (Elaphurus davidianus) through natural re-wilding. Sci Rep 2016; 6:27297. [PMID: 27272326 PMCID: PMC4895148 DOI: 10.1038/srep27297] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 05/13/2016] [Indexed: 11/18/2022] Open
Abstract
The Milu (Père David’s deer, Elaphurus davidianus) became extinct in China in the early 20th century but was reintroduced to the country. The reintroduced Milu escaped from a nature reserve and dispersed to the south of the Yangtze River. We monitored these accidentally escaped Milu from 1995 to 2012. The escaped Milu searched for vacant habitat patches as “stepping stones” and established refuge populations. We recorded 122 dispersal events of the escaped Milu. Most dispersal events occurred in 1998, 2003, 2006 and 2010. Milu normally disperse in March, July and November. Average dispersal distance was 14.08 ± 9.03 km, with 91.41% shorter than 25 km. After 5 generations, by the end of 2012, 300 wild Milu were scattered in refuge populations in the eastern and southern edges of the Dongting Lake. We suggest that population density is the ultimate cause for Milu dispersal, whereas floods and human disturbance are proximate causes. The case of the Milu shows that accidentally escaped animals can establish viable populations; however, the dispersed animals were subject to chance in finding “stepping stones”. The re-wilded Milu persist as a meta-population with sub-populations linked by dispersals through marginal habitats in an anthropogenic landscape.
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