Amazon floodplain hydrology and implications for aquatic conservation

1. The amplitude, duration, frequency, and predictability of runoff and inundation of aquatic habitats are key hydrological characteristics linked to aquatic ecosystem functioning and biodiversity, but they are seldom integrated into analyses of Amazon floodplain ecology. Remote sensing approaches, measurements and modelling of floodplain hydrology provide a basis for this integration.
2. Effective legislation to protect floodplains and other wetlands depends on operational definitions that require application of hydrological data.
3. Extent and changes of flooded areas are linked to fish diversity and to presence and growth of flooded forests and floating plants.
4. Dam construction reduces river system connectivity and modifies the flood pulse, with major negative implications for floodplain ecosystems adapted to and dependent on a natural flood regime.
5. Trends and variability in climate plus deforestation are altering the Amazon's hydrological cycle, causing changes in discharge and flooded area with concomitant ecological impacts.

     

Integrating freshwater wetland science into planning for Great Barrier Reef sustainability

1. The paper ‘Biodiversity values of remnant freshwater floodplain lagoons in agricultural catchments: evidence for fish of the Wet Tropics bioregion, northern Australia’, published in Aquatic Conservation: Marine and Freshwater Ecosystems in 2015, has contributed in several ways to the integration of freshwater wetland science within new catchment management policies and practices for Great Barrier Reef (GBR) sustainability.
2. The Tully–Murray biodiversity study developed novel protocols to sample larval, juvenile, and adult fish life‐history stages in floodplain lagoons using a combination of boat‐based backpack electrofishing and fyke netting. In addition, hydrological and hydrodynamic models were applied in a completely new way to quantify the timing, extent, and duration of water connectivity across floodplain streams, cane drains, and wetlands. Combining the two novel approaches enabled an analysis of lagoon fish assemblage patterns in relation to environmental gradients, especially floodplain hydrology, connectivity patterns, and measures related to agricultural land use.
3. In demonstrating the importance of different levels of connectivity for different biodiversity outcomes in freshwater floodplain lagoons of the Tully–Murray catchment, the subject paper established that floodplain connectivity needs to be taken into consideration in wetland management practices.
4. The timing of the subject publication was fortuitous. It coincided with the preparation of the evidence‐based 2017 Scientific Consensus Statement on land‐based water quality impacts on the GBR. As one of the few freshwater wetland ecology publications for the catchments of the GBR at that time, this paper played an important role in demonstrating freshwater wetland values, fish conservation options, and management imperatives to sustain wetland ecological health and services in GBR catchments.
5. By advancing the understanding of factors driving biodiversity patterns, and the importance of connectivity and ecohydrological processes in freshwater floodplain wetlands of the GBR catchment, the Tully–Murray study helped to drive new policy directives for the protection and restoration of catchment, floodplain, and estuary functions, and connectivity, now embedded in the Reef 2050 Long‐Term Sustainability Plan 2018, an overarching strategy for managing the GBR over the next 35 years, and complementary Queensland environmental legislation.

     

Brazilian wetlands: their definition,delineation, and classification for research,sustainable management,and protection

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Linking vegetation patterns,wetlands conservation,and ecosystem services provision: From publication to application

1. Natural wetlands emerge as the best sites to preserve the diversity of aquatic and riparian vegetation; however, especially in the lowlands, pristine wetlands and aquatic ecosystems have almost completely disappeared through land reclamation and agricultural development. Actions are needed, therefore, to maintain and recreate a wide network of wetlands able to preserve adequate levels of vegetation diversity.
2. Focusing on a complex wetland system located in an overexploited plain, the article entitled ‘The importance of being natural in a human‐altered riverscape: Role of wetland type in supporting habitat heterogeneity and the functional diversity of vegetation’, published in 2016 in Aquatic Conservation: Marine and Freshwater Ecosystems (AQC) explored the role of wetland origin and hydrology as the main drivers of physical and vegetation functional diversity, following a hierarchical sampling approach.
3. The main results reinforced the key contribution of natural sites in maintaining vegetation diversity in heavily impaired riverine contexts, suggesting a direct effect of the interannual and seasonal dynamics of water‐level variations in the observed vegetation patterns.
4. The article offered an important contribution to our knowledge of vegetation patterns in wetlands, partly attributed to the innovative functional, hierarchical approach applied which is able to guarantee reliable data on the distribution patterns of physical heterogeneity and wetland vegetation.
5. The findings of the article have been applied and adopted in a series of technical handbooks designed, inter alia, to support the monitoring programmes of habitats of community interest or vegetation of relevance for aquatic biodiversity conservation. In addition, this article has helped to raise awareness of the essential roles played by wetlands in agricultural landscapes and has emphasized the need for a better synergy between the European Habitats Directive and the Water Framework Directive. Several ecological recovery projects have been funded in line with the results described in the AQC article.

     

Characterizing seasonal dynamics of Amazonian wetlands for conservation and decision making

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A methodology for evaluating the sustainability of inland wetland systems

Sustainable development is a process in which present and future human needs can be satisfied without degrading the socio-environmental systems that they rely upon. Inland wetlands are diverse ecosystems that provide numerous goods and services. Current wetland evaluation methodologies include inventories, monitoring of hydrological and climatic variables, population dynamic studies, mechanistic models, the use of geographical information systems, and measuring of biotic indices. Sustainability evaluation methods, which combine in a systemic approach production efficiency, ecosystem function, environmental services, and social values are required. In this study, a methodological framework was developed and applied to a case in the High Lerma River Basin in Central Mexico. Criteria and indicators comprising the environmental, economic, and social dimensions, as well as systemic attributes such as productivity, stability, resilience, self-reliance, and equity were derived and measured to evaluate wetland management systems. Native species were compared to the predominant carp monoculture system. Results from the evaluated indicators showed that the native species multicultural management system can be a feasible, profitable, and self-reliant conservation and utilization alternative. Some difficulties were faced in finding reliable estimates to be used as reference values, and potential indicators for future, long-term evaluations are proposed. The application of sustainability indicators to wetland management proved to be an objective and trustworthy methodological alternative, which could increase both wetland sustainability and the continuous development of integrated assessment tools for its evaluation.     

Assessing the relative impacts of land‐use change and river regulation on Burdekin River (Australia) floodplain wetlands

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１９８７－２００４年洞庭湖典型湿地类型动态分析

洞庭湖湿地是我国重要的湖泊湿地,先后经历了大范围围湖造田和退田还湖。选取1987年12月、1995年12月和2004年12月3期TM遥感影像,通过决策树分类方法对其进行分类,计算土地利用类型转移矩阵,对洞庭湖典型湿地类型面积动态变化进行分析,以了解1987-2004年退田还湖前后自然湿地与人工湿地相互转化状况,为今后洞庭湖湿地保护提供数据支撑。结果表明,1987-2004年,人工湿地减少,自然湿地增长,增长主要集中在草滩地和芦苇滩地,草滩地增长速率为23.85km2/a,芦苇滩地增长速率为1.97km2/a。1987-1995年,尽管湿地总体上呈现增长,但自然湿地退化严重;1995-2004年,人工湿地呈现下降趋势,在自然湿地中,水域与泥沙滩地总体变化不明显,芦苇滩地与草滩地呈现增长。退田还湖对湿地保护起到了主要作用,但仍存在一些围湖造田现象,退田还湖工程实施没有得到完全落实。     

Quantifying anthropogenic nutrient sources and loadings within a small catchment with conservation interests,eastern Scotland

This paper demonstrates the possibility of quantifying sub-catchment nutrient budgets from routinely monitored hydrological and hydrochemical data. The relative importance of a number of potential anthropogenic nutrient sources was quantified for a small catchment in Scotland. Within the catchment there are two Sites of Special Scientific Interest, including two lochs and a floodplain mire. The study was undertaken to provide information for prescribing strategies to safeguard the conservation interests of these aquatic systems. The principal source of nitrate was found to be groundwater. Phosphate and ammonium loadings were greatest in surface run-off. The evidence indicates that the greatest contributor towards these nutrient sources is agriculture. Even when conservative estimates of losses were applied, current fertilizer and animal inputs could account for present day nutrient loadings. In addition, changes in the area under arable farming and under individual crops during the past 30 years are consistent with trends in nitrate and phosphate loads. Nutrient inputs from sewage works overflows and septic tanks within the catchment were estimated to be small. Leachate from a landfill site within the catchment was also not considered to be a major source of nutrients, but a more intensive water quality monitoring programme would be needed to confirm the absence of leachate plumes. The only long-term solution to reducing nutrient loadings to the aquatic systems is a reduction in agricultural activities within the catchment and avoidance of fertilizer and slurry applications near water sources. Diversion of drainage ditch waters supplying the floodplain mire is also a possibility but the hydrological consequences of such an action could induce more severe degradation than that due to nutrient enrichment.     

黄河下游湿地演变与实测径流相关性研究

探索不同类型河道湿地面积与水文站实测径流量的相关性,为黄河流域生态保护修复和管理工作提供支撑。选择黄河下游花园口-利津河段为研究对象,基于1986、1990、2000、2010和2020年5期遥感解译黄河下游湿地的类型、面积和格局,分析湿地动态变化及原因,结合黄河下游重要水文站实测径流量数据,探索黄河下游不同类型河道湿地面积变化与径流相关性。结果表明：（1）河流水面湿地为黄河下游河段湿地的主要组成部分,占湿地面积的45.9%～65.9%;(2)黄河下游河段的湿地面积从20世纪80年代至今呈现萎缩趋势,面积减少约35.6%,但萎缩速度在不断减缓,湿地面积逐渐趋于稳定;（3）黄河下游游荡型、弯曲型和顺直型河段的湿地面积与径流量的相关性存在差异。游荡型和弯曲型河段河流水面面积与流量均呈正相关关系,但变化幅度不同,顺直型河段河流水面面积受流量的影响较弱,游荡型、弯曲型和顺直型河段滩地面积随径流量增大而减少,减少幅度各有差异。     

Recent human‐induced salinity changes in Ramsar‐listed Orielton Lagoon,south‐east Tasmania,Australia: a new approach for coastal lagoon conservation and management

• 1. Many coastal lagoons in eastern Australia have changed as a result of recent human activities. However, it is often difficult to determine the extent of change and the ecological implications. A palaeoecological approach allows a quantitative assessment of how an aquatic ecosystem changes and responds to human impacts beyond what is possible with historical data or monitoring programmes.
• 2. Orielton Lagoon (south‐east Tasmania, Australia) is a Ramsar‐listed coastal wetland of international importance for conservation. This study was undertaken at the site to determine whether recent anthropogenic hydrological modifications to the lagoon had influenced its ecology, particularly salinity, and compromised its Ramsar status.
• 3. A diatom–salinity transfer function was constructed from a training data set of 96 diatom taxa from 34 sampling sites in 19 lagoons along the east coast of Tasmania.
• 4. The salinity of Orielton Lagoon has changed in response to a causeway constructed across its mouth, which has transformed the lagoon from an open marine environment to an enclosed, virtually stagnant, brackish water body.
• 5. These changes have compromised the protected coastal wetland status of Orielton Lagoon. Environmental remediation attempts have since partially restored the natural hydrology of the lagoon and it is now returning towards the state it was in prior to causeway construction.
• 6. A palaeoecological approach using diatoms was found to be successful in reconstructing recent salinity changes and investigating human impacts on Orielton Lagoon over the last 50–55 years.

Copyright © 2006 John Wiley & Sons, Ltd.     

Developing a standard approach for assessing the hydromorphology of lakes in Europe

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Desktop classification of inland wetlands for systematic conservation planning in data‐scarce countries: mapping wetland ecosystem types,disturbance indices and threatened species associations at country‐wide scale

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The characterization and classification of the Black River Upper Morass,Jamaica, using the three‐parameter test of vegetation,soils and hydrology

• 1. The characterization and classification of the Black River Upper Morass was conducted using the criteria of the three‐parameter test for vegetation, soils and hydrology at 14 sites within the study area.
• 2. The Upper Morass exhibited 71% hydrophytic vegetation typical of wetlands (vascular and non‐vascular plants including Cladium jamaicense, Phragmites australis, Typha angustifolia and Sagittaria lancifolia) and 29% vegetation atypical of wetlands.
• 3. The Upper Morass is classified as a Palustrine System with sub‐classes of Aquatic Bed and Persistent Emergent Wetland.
• 4. The presence throughout the Upper Morass of monoculture stands of the invasive species Eichhornia crassipes and Typha domingensis, which are known to invade disturbed or partially drained wetlands, confirmed that the study area was a disturbed ecosystem.
• 5. The Upper Morass exhibited hydric (flood‐water and groundwater) soils, which, in association with its temporarily flooded and saturated wetland hydrology, indicated that it is groundwater‐driven.
• 6. Application of the three‐parameter test indicated a linkage between the functions of the Upper Morass and the Lower Morass, and thus a need for conservation of the Black River Morass System as a single unit rather than two independent wetlands. Two key instruments of conservation will be further detailed ecological assessments and the implementation of a management plan.

Copyright © 2006 John Wiley & Sons, Ltd.     

Managed and natural inundation: benefits for conservation of native fish in a semi‐arid wetland system

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人工湿地堵塞监测方法的研究进展

人工湿地堵塞是目前国内外研究的热点问题,精确、高效的监测方法对提升湿地运行管理及净化能力等有重要意义。总结前人研究成果,比较分析目前人工湿地堵塞常见和可能的监测方法,对人工湿地堵塞监测方法和装置设备的研究方向及重点进行了展望,以期为堵塞湿地的长期监测提供参考。根据湿地内部水力学分析、基质或堵塞物物理化学性质将监测方法分为原位法和异位法。原位法中基于水力传导率测定的下降水头法和恒定水头法应用广泛;示踪剂技术较为简明直观,常用作堵塞湿地水流模型的建立;时域反射探针、探地雷达以及核磁共振传感器等新型原位探针技术对湿地内部造成的干扰较小,在湿地堵塞物定性定量方面具有良好发展前景;基于湿地内部电阻效应的微生物燃料电池法是目前研究的热点;基于基质孔隙率和堵塞物成分和性质的异位测定法还有较大提升空间;新兴的以蚯蚓为主的生物监测和根区微生物监测同样值得探索。     

Knowledge gaps and challenges for conservation of Mediterranean wetlands: Evidence from a comprehensive inventory and literature analysis for Sardinia

1. Wetlands are some of the most important ecosystems on Earth. They play a key role in mitigating climate change-related events and filtering polluted water, and provide habitats for a wide range of species. Despite their importance, and numerous regulations that support their conservation, wetlands continue to be destroyed. Recent reports have indicated a progressive decline in ecological character of remaining wetlands.
2. This research reviews and extends the present status of wetland knowledge in Sardinia, the second largest Mediterranean island. For the first time, Sardinian wetlands were comprehensively mapped using satellite images and field validation. Impacts were also assessed. Trends in literature published about Sardinian wetlands since 1900 were then analysed, mainly according to the location(s) and topic(s) studied.
3. In total, 2,501 Sardinian wetland sites were identified. The most common impacts observed in the field were vegetative degradation and water pollution. Of these wetlands, 2,274 have never been the subject of a research paper. Despite recent increases in publication rates, there was a lack of even basic knowledge about many wetlands, especially smaller ones. Larger wetlands have been studied from a range of viewpoints.
4. In the light of these results, suggestions for improved awareness, effective management and conservation of Mediterranean wetlands were established. Future work should be directed to filling gaps in basic information, and to improvements in research and conservation, which might include multidisciplinary approaches in support of more comprehensive conservation management plans.

     

Developing a standard approach for monitoring freshwater pearl mussel (Margaritifera margaritifera) populations in European rivers

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Ecology,management, and conservation implications of North American beaver (Castor canadensis) in dryland streams

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