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Social-ecological networks (SENs) represent the complex relationships between ecological and social systems and are a useful tool for analyzing and managing ecosystem services. However, mainstreaming the application of SENs in ecosystem service research has been hindered by a lack of clarity about how to match research questions to ecosystem service conceptualizations in SEN (i.e., as nodes, links, attributes, or emergent properties). Building from different disciplines, we propose a typology to represent ecosystem service in SENs and identify opportunities and challenges of using SENs in ecosystem service research. Our typology provides guidance for this growing field to improve research design and increase the breadth of questions that can be addressed with SEN to understand human-nature interdependencies in a changing world.

Environmental flows are designed to enhance aquatic ecosystems through a variety of mechanisms; however, to date most attention has been paid to the effects on habitat quality and life-history triggers, especially for fish and vegetation. The effects of environmental flows on food webs have so far received little attention, despite food-web thinking being fundamental to understanding of river ecosystems. Understanding environmental flows in a food-web context can help scientists and policy-makers better understand and manage outcomes of flow alteration and restoration. In this paper, we consider mechanisms by which flow variability can influence and alter food webs, and place these within a conceptual and numerical modelling framework. We also review the strengths and weaknesses of various approaches to modelling the effects of hydrological management on food webs. Although classic bioenergetic models such as Ecopath with Ecosim capture many of the key features required, other approaches, such as biogeochemical ecosystem modelling, end-to-end modelling, population dynamic models, individual-based models, graph theory models, and stock assessment models are also relevant. In many cases, a combination of approaches will be useful. We identify current challenges and new directions in modelling food-web responses to hydrological variability and environmental flow management. These include better integration of food-web and hydraulic models, taking physiologically-based approaches to food quality effects, and better representation of variations in space and time that may create ecosystem control points.

Pesticides are increasingly recognised as a threat to freshwater biodiversity, but their specific ecological effects remain difficult to distinguish from those of co-occurring stressors and environmental gradients. Using mesocosms we examined the effects of an organophosphate insecticide (malathion) on stream macroinvertebrate communities concurrently exposed to a suite of stressors typical of streams in agricultural catchments. We assessed the specificity of the SPEcies At Risk index designed to determine pesticide effects in mesocosm trials (SPEARmesocosm). This index determines the log abundance proportion of taxa that are considered physiologically sensitive to pesticides. Geographic variation in pesticide sensitivity within taxa, coupled with variation between pesticides and the effects of co-occurring stressors may decrease the accuracy of SPEARmesocosm. To examine this, we used local pesticide sensitivity assessments based on rapid toxicity tests to develop two new SPEAR versions to compare to the original SPEARmesocosms index using mesocosm results. We further compared these results to multivariate analyses and community indices (e.g. richness, abundance, Simpson's diversity) commonly used to assess stressor effects on biota. To assess the implications of misclassifying species sensitivity on SPEAR indices we used a series of simulations using artificial data. The impacts of malathion were detectable using SPEARmesocosm, and one of two new SPEAR indices. All three of the SPEAR indices also increased when exposed to other agricultural non-pesticide stressors, and this change increased with greater pesticide concentrations. Our results support that interactions between other non-pesticide stressors with pesticides can affect SPEAR performance. Multivariate analysis and the other indices used here identified a significant effect of malathion especially at high concentrations, with little or no evidence of effects from the other agricultural stressors.

Managing ecosystems to provide ecosystem services in the face of global change is a pressing challenge for policy and science. Predicting how alternative management actions and changing future conditions will alter services is complicated by interactions among components in ecological and socioeconomic systems. Failure to understand those interactions can lead to detrimental outcomes from management decisions. Network theory that integrates ecological and socioeconomic systems may provide a path to meeting this challenge. While network theory offers promising approaches to examine ecosystem services, few studies have identified how to operationalize networks for managing and assessing diverse ecosystem services. We propose a framework for how to use networks to assess how drivers and management actions will directly and indirectly alter ecosystem services.

Investigating how environmental factors influence within-species trait variability is critical to understanding the evolution and maintenance of individual behavioural differences (i.e. temperament or personality), and their integration into wider ecological theory. Populations of Australian desert gobies, Chlamydogobius eremius , from starkly contrasting aquatic environments in arid Australia were used to investigate how environmental differences influence temperament traits. Focusing on boldness and exploration, fish were assessed using novel environment, dispersal and novel food item assays under laboratory conditions. The results of these experiments were analysed for repeatability and for patterns of divergence within and between populations. We found consistent within-species differences in novel environment and novel food item assays, with refuge emergence and inspection latency of a novel food item both strongly repeatable behavioural axes. Although both traits can be considered measures of boldness, refuge emergence significantly diverged according to sex, while inspection latency was predicted by habitat differences. This suggests that multiple measures of boldness are diverging independently according to different ecological drivers. Specifically, we found that fish caught from environments without predators and with probable intense intraspecific competition are less active and bolder in a novel food item context. Further analysis demonstrated how extreme habitat differences are driving behavioural divergence on multiple axes, relating to boldness and dispersal behaviours. This provides valuable insights into how the environment and behaviour interact and how we define temperament traits, as well as highlighting the importance of studying temperament within a community ecology context.

Constructed wetlands are commonly used to remove contaminants such as heavy metals from stormwater. However, metals can become bioavailable and be transferred into and along wetland food chains. Our study sought to establish whether urbanisation affected concentrations of metals in water, wetland sediments, freshwater crayfish and fish tissues. Samples were taken from constructed wetlands in western Melbourne. There was no relationship between catchment total imperviousness (TI, an index of urbanisation) and water column and sediment concentrations of metals with the exception of Zn, which was higher in more urbanised catchments. Concentrations of metals in fish tissues were highest in benthic species but declined with increasing body size and trophic level. This suggests that metals are not bioaccumulating or biomagnifying along food chains in these systems. Metabolic activity can differ between smaller and larger fish, or smaller fish may also be feeding on different food sources. Our results suggest that there is not a major human health risk associated with accumulation of metals in large-bodied fish in these wetlands, and that most of the metal load is retained in sediments, or the lowest trophic levels.

Traits provide key ecological information that can be applied to understanding the mechanisms which drive community assembly and persistence. In recent years, trait information has provided important insights into the responses of communities to stressors including pollutants and climatic extremes. Outside of Europe and North America, the use of stream macroinvertebrate traits has generally been hindered by the lack of a national database assigning traits to taxa. Here, we present an integrated database for Australian stream macroinvertebrates, which for the first time brings together data from multiple jurisdictions to facilitate the use of traits in both theoretical and applied studies. We describe the database and discuss its applications as well as challenges and limitations of this and other trait databases. The Australian trait database provides new opportunities for research and application in freshwater management.

Aquatic ecosystems in arid environments provide important refugia and ‘stepping-stones’ of connectivity for aquatic fauna. Aquatic ecosystems in central Australia are vulnerable to degradation due to the impacts of invasive herbivores such as camels, which degrade small desert waterbodies through drinking, trampling, and fouling with dung. In this study we assessed the impacts of camel dung on the water quality and macroinvertebrate colonization and community composition of small arid zone freshwater pools using experimental mesocosms. Camel dung (2 kg) was added to half the mesocosms (the treatment), the remaining mesocosms (without camel dung) acted as the controls. All mesocosms were sampled weekly for water quality, nutrients, chlorophyll a and macroinvertebrate richness and abundance, over an eight week period during summer. Macroinvertebrate abundance was higher in the control mesocosms in comparison to the treatment mesocosms. Pollution tolerant taxa such as mosquito larvae were common in treatment mesocosms, while sensitive fauna, such as larval mayflies and dragonflies were more common in the controls. The latter are predators and appeared to have a major influence on community composition. Our results reinforce the need for active management of invasive herbivores to protect aquatic biodiversity and to manage potential disease-vector species in central Australia waterbodies.

Plant condition, analysed using fluoroscopy and morphological characteristics and, genetic structure using microsatellite markers and chloroplast DNA sequences was studied in Phragmites australis in the Gippsland coastal wetlands, SE Australia. Gene flow appeared regular and widespread between populations of P. australis in the Gippsland Lakes with some local genetic structure and no clear association with salinity. There was no genetic evidence of either salt tolerant or introduced variants.

Mosses provide habitat for microarthropod communities that are dominated in abundance and richness by mites. Although these systems are used as experimental models to address questions of relevance to general ecology, and despite the fact that they are also of relevance to key, ecosystem-wide functions such as nutrient cycling rates, the trophic relationships that underpin these functions are poorly resolved. The complexity of the moss habitat matrix and the small size of its residents have hampered progress in the determination of diets. We use stable isotope analysis of moss communities and present tools that allow for more in-depth studies of food web structure in mosses and soils than are currently available. We test in mites for the first time the association between mouthpart morphology and isotope signatures. Isotopes capture the diet of mites under field conditions and over a longer time-span than traditional, snapshot measures of diet such as gut contents analyses. Our data suggest that cheliceral morphology can be used as a first inexpensive and quick filter for estimation of dietary preference in mites, with ambiguous trophic relationships resolved through isotope analyses. This work provides new information and tools for the study of mite-dominated food webs.

Effects of riparian harvesting on in-stream biota were monitored in five streams in exotic conifer plantations that differed in how logs were extracted, patterns in deposition of woody debris, and the degree to which riparian buffers were retained. Streams were sampled on three occasions in summer, once prior to harvesting and twice afterwards. Consistent effects of harvesting included an increase in the amount of woody debris in the channel, increased fine sediment and a trend towards higher algal productivity. Invertebrate communities changed dramatically in some streams. General patterns included an increase in small sized taxa and taxa with generalist diets in the first year after harvest, then a trend towards a greater representation of grazers and larger taxa the following year. Responses in particular taxa were highly variable between streams. Some of this variability was related to forestry management, the least dramatic changes occurring where a narrow riparian buffer strip was retained. Reduced impacts were also observed in streams where woody debris was piled over the channel. We suggest that management practices that maintain shading of the stream channel will moderate forestry effects, and that practices such as channel cleaning are likely to be detrimental.

Efficiency in biomonitoring studies is essential to maximize return (i.e. useful data) for investment (e.g. time, training, personnel). Here, we test several options for reducing data resolution when streamlining monitoring protocols, and use the results as a framework to discuss the costs and benefits of decreasing information when sampling intertidal assemblages. Specifically, we ask; (1) Is it necessary to collect species abundance data, or is species presence–absence information sufficient to differentiate sites? (2) Is it necessary to sample organismal abundance at the species-level or is coarser (higher taxon or functional group) resolution sufficient to resolve patterns of difference in intertidal community structure? and (3) How general are these patterns across different oceanic regions? We answer these questions using data from Northeast Atlantic, Northwest Atlantic, Northeast Pacific, and Southwest Pacific intertidal monitoring studies. Results show that compared to species-level sampling, genus-level sampling requires knowledge of 25% fewer taxa, but results in only a 5% difference in the ability to discern between-sample similarities. Likewise, family-level sampling involves 50% fewer taxa, and is accompanied by only an 8% difference in between-sample similarities. Species lists and functional groups were variable in performance, working well for some regions, and poorly for others. These findings will assist in the selection of monitoring protocols with the potential for increased geographic scope and temporal frequency of sampling, resulting in longer time series of data collection, and a reduction in the required taxonomic skills for individuals involved in scientifically useful biomonitoring programs.

In their recent TREE review, Russ Landeweert et al.1xLinking plants to rocks: ectomycorrhizal fungi mobilize nutrients from minerals. Landeweert, R. et al. Trends Ecol. Evol. 2001; 16: 248–254Abstract | Full Text | Full Text PDF | PubMed | Scopus (295)See all References1 describe how ectomycorrhizal fungi enclose and penetrate mineral grains and mobilize nutrients from alkali feldspar minerals by producing organic acid. This allows plants with mycorrhizal fungi to access nutrients that are inaccessible to roots 1xLinking plants to rocks: ectomycorrhizal fungi mobilize nutrients from minerals. Landeweert, R. et al. Trends Ecol. Evol. 2001; 16: 248–254Abstract | Full Text | Full Text PDF | PubMed | Scopus (295)See all References1. By such means, important macronutrients might be made available from mineral sources, for example phosphate from the mineral apatite, and potassium (K) from biotite.Landeweert et al. identify nitrogen (N) as the most important limiting nutrient in boreal forests, and the only major nutrient that cannot be derived from mineral sources. This is in line with the widely held view, perpetuated in ecology textbooks 2xBegon, M. et al. CrossrefSee all References2, that the atmospheric phase is of over-riding importance in N cycles. However, there is increasing evidence for significant amounts of N in rocks, and the same fungal processes reported by Landeweert et al. might also make rock-based N accessible to plants. Diagenesis of N into rocks can occur when organic matter comes into contact with clays in an anoxic environment. The resulting N compounds can substitute for alkali ions in silicates, such as feldspars, micas and zeolites. Ramseyer et al.3xAuthigenic K–NH4–feldspar in sandstones: a fingerprint of the diagenesis of organic matter. Ramseyer, K. et al. J. Sediment. Petrol. 1993; 63: 1092–1099See all References3 found significant amounts of K–NH4–feldspars in Miocene shales, and large amounts of N have been found in granites 3xAuthigenic K–NH4–feldspar in sandstones: a fingerprint of the diagenesis of organic matter. Ramseyer, K. et al. J. Sediment. Petrol. 1993; 63: 1092–1099See all References3, sandstones 4xThe abundance of ammonium in the granites of central Spain, and the behaviour of the ammonium ion during anatexis and fractional crystallization. Hall, A. et al. Mineral. Petrol. 1996; 56: 105–123CrossrefSee all References, 5xGeologic nitrogen: a potential geochemical hazard in the San Joaquin Valley, California. Strathouse, S.M. et al. J. Environ. Qual. 1980; 9: 54–60CrossrefSee all References, 6xDiagenesis of ammonium during hydrocarbon maturation and migration, Wilcox Group, Louisiana, USA. Williams, L.B. et al. Appl. Geochem. 1992; 7: 123–134Crossref | Scopus (53)See all References, mudstones 5xGeologic nitrogen: a potential geochemical hazard in the San Joaquin Valley, California. Strathouse, S.M. et al. J. Environ. Qual. 1980; 9: 54–60CrossrefSee all References, 6xDiagenesis of ammonium during hydrocarbon maturation and migration, Wilcox Group, Louisiana, USA. Williams, L.B. et al. Appl. Geochem. 1992; 7: 123–134Crossref | Scopus (53)See all References, slates and schists 7xContribution of bedrock nitrogen to high nitrate concentrations in stream water. Holloway, J.M. et al. Nature. 1998; 22: 785–788See all References7. Holloway et al.8xNitrogen release from rock and soil under simulated field conditions. Holloway, J.M. et al. Chem. Geol. 2001; 174: 403–414Crossref | Scopus (26)See all References8 showed that artificial weathering of rocks that contain N yielded both ammonium and nitrate. Biological weathering by ectomycorrhizal fungi could increase the accessibility of this N source.Recent research in New Zealand has shown high concentrations of ammonium (228–1348 μg l−1) in groundwater in locations where the schist bedrock is rich in N (121–809 mg N kg−1 rock: R.M. Thompson, PhD thesis, University of Otago, 2001). Not only is this groundwater source a potential N subsidy for terrestrial plants, but it can also be converted to nitrate by ecosystem processes in streams and other aquatic systems 9xNitrogen transformations in a small mountain stream. Richey, J.S. et al. Hydrobiologia. 1985; 124: 129–139Crossref | Scopus (43)See all References, 10xRegulation of nitrification in aquatic sediments by organic carbon. Strauss, E.A. and Lamberti, G.A. Limnol. Oceanogr. 2000; 45: 1854–1859CrossrefSee all References. Thus, in streams in locations in New Zealand where groundwater ammonium is high, nitrate concentrations are also unusually elevated (400–3000 μg l−1), fuelling algal productivity. Several studies have implicated bedrock N in high concentrations of nitrate in streams 5xGeologic nitrogen: a potential geochemical hazard in the San Joaquin Valley, California. Strathouse, S.M. et al. J. Environ. Qual. 1980; 9: 54–60CrossrefSee all References, 7xContribution of bedrock nitrogen to high nitrate concentrations in stream water. Holloway, J.M. et al. Nature. 1998; 22: 785–788See all References (R.M. Thompson, PhD thesis, University of Otago, 2001). Holloway et al.7xContribution of bedrock nitrogen to high nitrate concentrations in stream water. Holloway, J.M. et al. Nature. 1998; 22: 785–788See all References7 estimate that up to 20% of the global N inventory might be included in bedrock. Landeweert et al. provide a novel mechanism for the utilization of this resource by terrestrial plants with ectomycorrhizal fungi, but geological N might also be a significant resource in aquatic ecosystems.