Existing freshwater monitoring networks are often designed to report on the state and trend of freshwater variables but may be poorly adapted to establishing cause-effect relationships between mitigation actions (e.g., riparian buffers, wetland restoration, stock exclusion) and their effect (e.g., reduced contaminant load, improved ecological health). Time lags, attenuation and biogeochemical processing vary with the contaminant and across different components of freshwater systems (e.g., groundwater, rivers, lakes), making it challenging to use conventional ‘state of the environment’ methods for change detection. In the United Nations Water Action Decade (2018-28) and Decade on Restoration (2021-2030), we will increasingly require quantitative evidence that specific policies or land management actions have improved the health of our freshwater ecosystems and represent value for money. Unless we complement State of the Environment reporting with mitigation-specific monitoring, we will not be able to report robustly on the benefits of the large investments in effort and resources to improve freshwater resources and establish enduring policies. The aim of this session is to review opportunities for comprehensively monitoring the improvement of freshwater health by land mitigation, land use and practice management, and in-system (e.g., in-lake, in-stream) actions. We seek presentations that provide an integrated approach that engages scientists, managers, traditional owners, environmental economists and decision makers in optimizing monitoring programs for change detection. This session will include: review of the suitability of existing monitoring networks to detect freshwater improvement from a mitigation plan; design of optimized networks that take advantage of new and emerging technologies (e.g., remote sensing, GIS, in-situ sensors, visualization) to detect the effects of the mitigation plan; and use of culturally-based monitoring approaches for change detection.
Additional Chairs: Ellen Moon & Martino Malerba
Agriculture and urbanization have greatly altered the earth’s land area and created a new group of ‘artificial’ aquatic ecosystems. These human-made (anthropogenic) waters include those that have been substantially modified from their natural state and those that have been created where no waterbody existed before. Artificial aquatic systems are prominent features of human landscapes and are directly impacted by agriculture and urbanization. They have been engineered, created or modified to serve a particular purpose and offer ecosystem services including flood abatement, water quality improvement, sediment containment, and biodiversity enhancement. Artificial aquatic ecosystems range from large reservoirs such as hydroelectric dams to the smaller lentic and lotic aquatic systems such as urban ponds, farm dams, constructed wetlands, canals, storm drains, urban and agricultural channels. Yet while these artificial systems are now ubiquitous across landscapes, we know little about their effects on freshwater ecosystems. In this session, we invite talks and poster presentations that explore the ecological, chemical, hydrologic, and biogeochemical functioning of all kinds of constructed and altered aquatic environments across agricultural and urban landscapes. We welcome studies from multiple disciplines, including hydrology, aquatic biogeochemistry, carbon accounting (including greenhouse gas emissions), water quality and engineering, that advance the mechanistic understanding of this emerging field in freshwater science.
The threat of global warming and anthropogenic alterations to freshwater species, processes and ecosystems, has been clearly articulated and the protection of freshwater biodiversity is recognized as a major conservation challenge. All freshwater ecosystems are vulnerable because of their relative isolation and physical fragmentation within a terrestrial landscape. Freshwater ecosystems in arid environments are especially vulnerable because of their isolation by large tracts of dry lands, or deserts, and the impacts of climatic extremes. Under the global warming scenario of drier regions becoming drier, and more extreme rainfall events creating catastrophic flooding, unprecedented changes in arid land hydrological regimes are likely to occur. Water quality will also be adversely affected. For example, the decline in oxygen solubility with increasing water temperatures will have a direct deleterious impact on many freshwater species. Species extinctions will occur when the thermal tolerances of freshwater species are exceeded and recolonisation pathways between arid land waterbodies are disrupted by extended droughts. Competition between water-dependent arid land birds and bats for diminishing water resources, and inherent dispersal limitations to finding ever rarer water sources, may result in local extinctions of terrestrial species as well. Additionally, the effects of anthropogenic water withdrawals and water resource management decisions under warming climatic scenarios will be amplified within arid environments. This symposium will examine the conservation challenges facing arid land freshwater species and ecosystems under global warming across a range of hydrologic regimes and habitats, from intermittent streams and temporary rivers, to perennial springs. It will also facilitate the comparison of mitigation, adaptation, and conservation strategies at scales ranging from habitats to continents.
Group Discussion
Stream ecosystem processes have been viewed as spatially predictable within a network since the River Continuum Concept (RCC) and before. Additional conceptual proposals have been put forth since the RCC, including the river ecosystem synthesis, the network dynamics hypothesis, the pulse shunt concept, and the river network saturation concept. Additionally, the stream biome gradient concept posits that ecosystem processes should be predictable across large spatial scales based on climatic conditions. Ecosystem processes can vary within or among watersheds as influenced by shifts in climate and changes in land use. Across watersheds, for example, desert stream networks have contrasting properties to those in moist forests. Transitions within watersheds can also be important (e.g. savannah to tropical rainforest transitions in eastern Australia, alpine to coastal plain transitions in New Zealand, alpine to dry deserts in many parts of the world, and heterogeneous landscapes resulting from human activities). This session will focus on ecosystem-based processes such as metabolism, decomposition, nutrient cycling, and riparian-stream interactions within and among stream networks. We will focus specifically on spatially explicit comparisons of these processes and how they might link to existing conceptual models.
The African Chapter of SFS, the African Women in Science (AWIS) and the African Center for Aquatic Research and Education (ACARE) propose to host a special session at the SFS Conference in Brisbane Australia. This session will highlight research and projects in Africa, but also to continue the collaboration between African scientists and the SFS. The presentation topics are variable and keenly reflect the interest of our society in African freshwater ecosystems. Water pollution in Africa is one of the largest environmental threats to the health of human populations and food security. However, there is relatively little research explicitly directed towards this issue. Many of the presentations will focus on the ecology of one or several of the rift valley lake systems (Albertine rift and Gregory rift lakes). Rift Valley lakes are freshwater and home to an exceptional number of endemic species. Speakers in this session represent scientists from institutions in Africa who are conducting research specifically on biomonitoring and developing metrics to assess water pollution. In addition, many scientists will present current research initiatives on the quality of lotic systems in Africa. The call for presentations from our African colleagues was well received, suggesting an enthusiastic commitment to collaboration. We have received presentation titles from 13 speakers and respectfully request two sessions. To date collaborators include the University of Rwanda, Rhodes University in South Africa, Bahir Dar University in Ethiopia and the African Center for Aquatic Research and Education. However, we expect many more prior to the conference in June.
Additional Chairs: Ellen Moon & Martino Malerba
Group Discussion
Panel Discussion