Search Results (3)

With the growing demand for aquatic products, aquaculture has become a prominent means of meeting this demand. However, the selection of suitable sites for aquaculture remains a key factor in the success of any aquaculture operation. While various methods exist for site selection, geographic information system (GIS)-based multi-criteria evaluation (MCE) methods have emerged as the most widely utilized approach to identifying potential aquaculture sites. Following the guidelines of the preferred reporting items for systematic reviews and meta-analyses (PRISMA), this paper presents a systematic review and meta-analysis of GIS-based MCE methods used in aquaculture sites selection. The objective of this study is to offer a comprehensive overview of existing research in this field and develop a general model for selecting sites for fish and shellfish aquaculture. The main findings indicate a growing number of studies utilizing GIS-based MCE in aquaculture site selection in recent years, with Asia being the leading continent in terms of publications in this domain. Among the journals publishing in this field, the Aquaculture journal stands out as the top publisher. Using consistent criteria across the reviewed studies, two models have been generated, each consisting of four sub-models: water quality, soil quality, infrastructure, and socioeconomic factors; and topography, environment, and physical parameters. These models can aid future researchers and assist decision-makers in identifying optimal locations for aquaculture development. Full article

A wide variety of geographic information system tools and methods was used for pre-dam topography reconstruction and reservoir bottom surveying in two dam reservoirs in the Ohře River, Czech Republic. The pre-dam topography was reconstructed based on archival aerial imagery and old maps. The benefits and drawbacks of these methods were tested and explained with emphasis on the fact that not all processed archival data are suitable for pre-dam topography modeling. Bathymetric surveying of a reservoir bottom is presently routine, but in this study, we used a wide combination of bathymetric mapping methods (sonar, ground penetration radar, and sub-bottom profiler) and topographic survey tools (LiDAR and photogrammetry), bringing great benefits for bottom dynamic analysis and data cross-validation. The data that we gathered made it possible to evaluate the formation of the inflow deltas in the reservoirs studied and assess the sediment reworking during recent seasonal drawdowns. A typical inflow delta was formed in the deeper of the two studied reservoirs, while the summer 2019 drawdown caused the formation and incision of a temporary drawdown channel and erosive downstream transport of approximately 1/10 of the delta body thickness in approximately 1/10 of the delta transverse size. No inflow delta was formed in the shallower of the studied reservoirs, but unexpectedly extensive sediment reworking was observed in the inflow part of the reservoir. Both the studied reservoirs and the pre-dam river floodplain have accumulated historical contamination by risk elements such as As, Hg, Pb; thus, the enhanced erosion of existing sediment bodies expected in the future, owing to more frequent droughts and global climate change, will endanger the ecological quality of the water and solids outflowing from the reservoirs. Full article

The poles constitute 14% of the Earth’s biosphere: The aquatic Arctic surrounded by land in the north, and the frozen Antarctic continent surrounded by the Southern Ocean. In spite of an extremely cold climate in addition to varied topographies, the polar aquatic regions are teeming with microbial life. Even in sub-glacial regions, cellular life has adapted to these extreme environments where perhaps there are traces of early microbes on Earth. As grazing by macrofauna is limited in most of these polar regions, viruses are being recognized for their role as important agents of mortality, thereby influencing the biogeochemical cycling of nutrients that, in turn, impact community dynamics at seasonal and spatial scales. Here, we review the viral diversity in aquatic polar regions that has been discovered in the last decade, most of which has been revealed by advances in genomics-enabled technologies, and we reflect on the vast extent of the still-to-be explored polar microbial diversity and its “enigmatic virosphere”. Full article