Diatom index of Galela Lake, Halmahera, Indonesia in relation to human activities
- Soeprobowati, Tri, Saraswati, Tyas, Jumari, Jumari, Sari, Kenanga, Gell, Peter
- Authors: Soeprobowati, Tri , Saraswati, Tyas , Jumari, Jumari , Sari, Kenanga , Gell, Peter
- Date: 2023
- Type: Text , Journal article
- Relation: International Journal of Environmental Science and Technology Vol. 20, no. 7 (2023), p. 7707-7722
- Full Text: false
- Reviewed:
- Description: Diatoms, silicious microalgae, have been used successfully as bioindicators of water quality assessment in aquatic ecosystems. Diatoms have a degree of tolerance to the water quality and some diatoms are a good indicator for several water quality variables. Diatom indices have been developed to assess river water quality, mostly in Europe. This study aims to apply diatom indices developed in Europe for the tropical lake of Galela adjacent to residential areas influenced by human activities. Galela Lake is one of the biggest lakes in Halmahera Utara, Indonesia with its main functions being domestic water supply, irrigation, fisheries, and tourism. Human activities have impacted the area around the lake. The 90-cm and 85-cm long sediment cores were collected using a piston corer from Site 1 and 2, respectively. Sediment samples were sliced every 5 cm, separated from sediment by adding HCl and H2O2. The diatom valves were identified under a microscope with 1,000 × magnification. The water quality status of each layer was inferred with diatom indices performed using OMNIDIA software version 6.0. Forty-nine and 63 diatoms species were identified from Site 1 and Site 2, respectively. The number of species and diversity of diatoms was higher in the lower layers than those in the upper layers. The preserved diatom assemblages reflect past physical and chemical water quality. Generic Diatom Index and Specific Pollution Sensitivity Index provided the best evidence for change in Galela Lake—they integrated 70–100% of the diatom taxa from the sediment core samples. © 2022, The Author(s) under exclusive licence to Iranian Society of Environmentalists (IRSEN) and Science and Research Branch, Islamic Azad University.
Emerging threats and persistent conservation challenges for freshwater biodiversity
- Reid, Andrea, Carlson, Andrew, Creed, Irena, Eliason, Erika, Gell, Peter, Johnson, Pieter, Kidd, Karen, MacCormack, Tyson, Olden, Julian, Ormerod, Steve, Smol, John, Taylor, William, Tockner, Klement, Vermaire, Jesse, Dudgeon, David, Cooke, Steven
- Authors: Reid, Andrea , Carlson, Andrew , Creed, Irena , Eliason, Erika , Gell, Peter , Johnson, Pieter , Kidd, Karen , MacCormack, Tyson , Olden, Julian , Ormerod, Steve , Smol, John , Taylor, William , Tockner, Klement , Vermaire, Jesse , Dudgeon, David , Cooke, Steven
- Date: 2019
- Type: Text , Journal article
- Relation: Biological Reviews Vol. 94, no. 3 (2019), p. 849-873
- Full Text: false
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- Description: In the 12 years since Dudgeon et al. (2006) reviewed major pressures on freshwater ecosystems, the biodiversity crisis in the world's lakes, reservoirs, rivers, streams and wetlands has deepened. While lakes, reservoirs and rivers cover only 2.3% of the Earth's surface, these ecosystems host at least 9.5% of the Earth's described animal species. Furthermore, using the World Wide Fund for Nature's Living Planet Index, freshwater population declines (83% between 1970 and 2014) continue to outpace contemporaneous declines in marine or terrestrial systems. The Anthropocene has brought multiple new and varied threats that disproportionately impact freshwater systems. We document 12 emerging threats to freshwater biodiversity that are either entirely new since 2006 or have since intensified: (i) changing climates; (ii) e-commerce and invasions; (iii) infectious diseases; (iv) harmful algal blooms; (v) expanding hydropower; (vi) emerging contaminants; (vii) engineered nanomaterials; (viii) microplastic pollution; (ix) light and noise; (x) freshwater salinisation; (xi) declining calcium; and (xii) cumulative stressors. Effects are evidenced for amphibians, fishes, invertebrates, microbes, plants, turtles and waterbirds, with potential for ecosystem-level changes through bottom-up and top-down processes. In our highly uncertain future, the net effects of these threats raise serious concerns for freshwater ecosystems. However, we also highlight opportunities for conservation gains as a result of novel management tools (e.g. environmental flows, environmental DNA) and specific conservation-oriented actions (e.g. dam removal, habitat protection policies, managed relocation of species) that have been met with varying levels of success. Moving forward, we advocate hybrid approaches that manage fresh waters as crucial ecosystems for human life support as well as essential hotspots of biodiversity and ecological function. Efforts to reverse global trends in freshwater degradation now depend on bridging an immense gap between the aspirations of conservation biologists and the accelerating rate of species endangerment.
First human impacts and responses of aquatic systems : A review of palaeolimnological records from around the world
- Dubois, Nathalie, Saulnier-Talbot, Emilie, Mills, Keely, Gell, Peter, Battarbee, Rick, Bennion, Helen, Chawchai, Sakonvan, Dong, Xuhui, Francus, Pierre, Flower, Roger, Gomes, Doriedson, Gregory-Eaves, Irene, Humane, Sumedh, Kattel, Giri, Jenny, JeanPhilippe, Langdon, Peter, Massaferro, Julieta, McGowan, Suzanne, Mikomagi, Annika, Ngoc, Nguyen, Ratnayake, Amila, Reid, Michael, Rose, Neil, Saros, Jasmine, Schillereff, Daniel, Tolotti, Monica, Valero-Garces, Blas
- Authors: Dubois, Nathalie , Saulnier-Talbot, Emilie , Mills, Keely , Gell, Peter , Battarbee, Rick , Bennion, Helen , Chawchai, Sakonvan , Dong, Xuhui , Francus, Pierre , Flower, Roger , Gomes, Doriedson , Gregory-Eaves, Irene , Humane, Sumedh , Kattel, Giri , Jenny, JeanPhilippe , Langdon, Peter , Massaferro, Julieta , McGowan, Suzanne , Mikomagi, Annika , Ngoc, Nguyen , Ratnayake, Amila , Reid, Michael , Rose, Neil , Saros, Jasmine , Schillereff, Daniel , Tolotti, Monica , Valero-Garces, Blas
- Date: 2018
- Type: Text , Journal article , Review
- Relation: Anthropocene Review Vol. 5, no. 1 (2018), p. 28-68
- Full Text:
- Reviewed:
- Description: Lake sediments constitute natural archives of past environmental changes. Historically, research has focused mainly on generating regional climate records, but records of human impacts caused by land use and exploitation of freshwater resources are now attracting scientific and management interests. Long-term environmental records are useful to establish ecosystem reference conditions, enabling comparisons with current environments and potentially allowing future trajectories to be more tightly constrained. Here we review the timing and onset of human disturbance in and around inland water ecosystems as revealed through sedimentary archives from around the world. Palaeolimnology provides access to a wealth of information reflecting early human activities and their corresponding aquatic ecological shifts. First human impacts on aquatic systems and their watersheds are highly variable in time and space. Landscape disturbance often constitutes the first anthropogenic signal in palaeolimnological records. While the effects of humans at the landscape level are relatively easily demonstrated, the earliest signals of humaninduced changes in the structure and functioning of aquatic ecosystems need very careful investigation using multiple proxies. Additional studies will improve our understanding of linkages between human settlements, their exploitation of land and water resources, and the downstream effects on continental waters.
- Description: Lake sediments constitute natural archives of past environmental
- Authors: Dubois, Nathalie , Saulnier-Talbot, Emilie , Mills, Keely , Gell, Peter , Battarbee, Rick , Bennion, Helen , Chawchai, Sakonvan , Dong, Xuhui , Francus, Pierre , Flower, Roger , Gomes, Doriedson , Gregory-Eaves, Irene , Humane, Sumedh , Kattel, Giri , Jenny, JeanPhilippe , Langdon, Peter , Massaferro, Julieta , McGowan, Suzanne , Mikomagi, Annika , Ngoc, Nguyen , Ratnayake, Amila , Reid, Michael , Rose, Neil , Saros, Jasmine , Schillereff, Daniel , Tolotti, Monica , Valero-Garces, Blas
- Date: 2018
- Type: Text , Journal article , Review
- Relation: Anthropocene Review Vol. 5, no. 1 (2018), p. 28-68
- Full Text:
- Reviewed:
- Description: Lake sediments constitute natural archives of past environmental changes. Historically, research has focused mainly on generating regional climate records, but records of human impacts caused by land use and exploitation of freshwater resources are now attracting scientific and management interests. Long-term environmental records are useful to establish ecosystem reference conditions, enabling comparisons with current environments and potentially allowing future trajectories to be more tightly constrained. Here we review the timing and onset of human disturbance in and around inland water ecosystems as revealed through sedimentary archives from around the world. Palaeolimnology provides access to a wealth of information reflecting early human activities and their corresponding aquatic ecological shifts. First human impacts on aquatic systems and their watersheds are highly variable in time and space. Landscape disturbance often constitutes the first anthropogenic signal in palaeolimnological records. While the effects of humans at the landscape level are relatively easily demonstrated, the earliest signals of humaninduced changes in the structure and functioning of aquatic ecosystems need very careful investigation using multiple proxies. Additional studies will improve our understanding of linkages between human settlements, their exploitation of land and water resources, and the downstream effects on continental waters.
- Description: Lake sediments constitute natural archives of past environmental
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