Andrew Boulton

Andrew Boulton
University of New England (Australia) | UNE · Department of Environmental Science and Ecology

Professor

About

170
Publications
46,112
Reads
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14,467
Citations
Citations since 2016
29 Research Items
5524 Citations
20162017201820192020202120220200400600800
20162017201820192020202120220200400600800
20162017201820192020202120220200400600800
20162017201820192020202120220200400600800

Publications

Publications (170)
Article
Full-text available
River networks are among Earth’s most threatened hot-spots of biodiversity and provide key ecosystem services (e.g., supply drinking water and food, climate regulation) essential to sustaining human well-being. Climate change and increased human water use are causing more rivers and streams to dry, with devastating impacts on biodiversity and ecosy...
Article
Full-text available
Environmental impact assessment (EIA) relies on rigorous scientific assessment of all potential causal pathways by which large-scale developments may impact on valued assets in a region. Despite their importance to informed decision-making, many EIAs are flawed by incomplete analysis of causal pathways, limited spatial assessment and a lack of tran...
Article
Full-text available
Conceptual models underpin river ecosystem research. However, current models focus on continuously flowing rivers and few explicitly address characteristics such as flow cessation and drying. The applicability of existing conceptual models to nonperennial rivers that cease to flow (intermittent rivers and ephemeral streams, IRES) has not been evalu...
Article
Full-text available
1.Temporary streams are dynamic ecosystems in which mosaics of flowing, ponded and dry habitats support high biodiversity of both aquatic and terrestrial species. Species interact within habitats to perform or facilitate processes that vary in response to changing habitat availability. A natural capital approach recognizes that, through such proces...
Article
In forestry, selective timber harvesting best management practices (BMPs) are widely adopted to mitigate the effects of clearfell harvesting on stream ecosystems. However, there have been surprisingly few studies experimentally assessing the effects of selective harvesting on freshwater benthic macroinvertebrate assemblages and how anthropogenic di...
Article
Best management practices (BMPs) for forestry activities have been developed to mitigate the impacts of timber harvesting on stream ecosystems in New South Wales, Australia. These BMPs include selective harvesting within the catchment, exclusion of harvesting in riparian zones, and restrictions on harvesting and machinery operations during wet weat...
Article
Globally, the provision of groundwater‐supported ecosystem services is threatened by climate change, water extraction and other activities that alter groundwater regimes (defined as temporal dynamics in groundwater pressures, storage and levels). Research on how altered groundwater regimes affect the ecology and ecosystem services of diverse ground...
Chapter
In intermittent rivers and ephemeral streams (hereafter, IRES), hydrological connectivity mediated by either flowing or nonflowing water extends along three spatial dimensions—longitudinal, lateral, and vertical—and varies over time. Flow intermittence disrupts this connectivity, operating through complex hydrological transitions (e.g., between flo...
Chapter
Intermittent rivers and ephemeral streams (IRES) support diverse and sometimes distinctive aquatic invertebrate communities. Although flow intermittence has been linked to reduced taxa richness, the highly variable environmental conditions that characterize IRES can enhance both taxonomic and functional diversity, with different invertebrates chara...
Chapter
Ecosystem services (ES) are the benefits to human society that are directly attributable to the ecological functioning of ecosystems. To date, ES and their values in intermittent rivers and ephemeral streams (IRES) have been largely overlooked. This chapter discusses ES provided by IRES, the economic values attached to them, and how current underst...
Chapter
Intermittent rivers and ephemeral streams (hereafter, IRES) drain over half the world’s land surface. Although they abound in arid, semiarid, and Mediterranean regions, they also occur in well-watered areas. Despite this ubiquity, their ecology remains poorly understood and their ecosystem services and values unappreciated. Such ignorance has meant...
Chapter
The defining feature of all intermittent rivers and ephemeral streams (hereafter, IRES) is that they cease flow at some time. Many IRES dry to isolated pools but flow often continues through the hyporheic sediments below the streambed. If dry conditions persist, hyporheic flows may also cease and the streambed dries completely. Consequently, the fl...
Chapter
Intermittent rivers and ephemeral streams (hereafter, IRES) abound on every continent in every climate. Arguably the most globally abundant flowing waterway, their distribution is expanding in many parts of the world through climate change and intensifying human demand for fresh water. Yet IRES remain poorly studied, undervalued, and often mismanag...
Book
Intermittent Rivers and Ephemeral Streams: Ecology and Management takes an internationally broad approach, seeking to compare and contrast findings across multiple continents, climates, flow regimes, and land uses to provide a complete and integrated perspective on the ecology of these ecosystems. Coupled with this, users will find a discussion of...
Article
Full-text available
1. Intermittent rivers and ephemeral streams (IRES) are watercourses that cease flow at some point in time and space. Arguably Earth’s most widespread type of flowing water, IRES are expanding where Anthropocenic climates grow drier and human demands for water escalate. 2. However, IRES have attracted far less research than perennial rivers and are...
Book
The 20 chapters in this book synthesize the scattered information on intermittent rivers and ephemeral streams (IRES), exploring the effects of flow intermittence on geomorphology, hydrology, biogeochemistry, and ecology in these ecosystems. – Here, we distil this information into fourteen themes, most of which emphasize how intermittence and pulse...
Book
Intermittent rivers and ephemeral streams (IRES) contribute multiple ecosystem services (ES) that are not as widely recognized or appreciated compared with those of perennially flowing waters. – Different ES are provided by IRES at different stages of their flow regime although the inherent uncertainty of, for example, flow may influence the way pe...
Book
Intermittent rivers and ephemeral streams (IRES) are temporally dynamic ecosystems that can support a diverse and distinctive aquatic invertebrate fauna – Resistance and resilience mechanisms allow species and communities to persist in IRES during dry phases and to recolonize quickly once flow returns – Human influences including climate change and...
Book
Flow regimes (magnitude, frequency, duration, timing, and rates of change in flow events) of all intermittent rivers and ephemeral streams (IRES) are characterized by variable periods of zero flow, caused by processes at different scales and often exacerbated by human activities – When flow ceases, surface waters in many IRES dry to isolated pools...
Book
Intermittent rivers and ephemeral streams (IRES) are flowing waters that cease flow and/or dry at some point along their course. Multiple natural and anthropogenic processes generate flow intermittence which influences almost every biogeochemical and ecological process in IRES. IRES are dynamic mosaics of flowing, nonflowing water and terrestrial h...
Article
Over the last two decades, there has been increasing public and political recognition of society's dependency upon natural habitat complexity and ecological processes to sustain provision of crucial ecosystem services, ranging from supplying potable water through to climate regulation. How has the ecosystem-services perspective been integrated into...
Article
Plant litter breakdown is a key ecological process in terrestrial and freshwater ecosystems. Streams and rivers, in particular, contribute substantially to global carbon fluxes. However, there is little information available on the relative roles of different drivers of plant litter breakdown in fresh waters, particularly at large scales. We presen...
Chapter
Connectivity of floodplains with their river channels affects invertebrates and habitat quality, and many invertebrates move between rivers and floodplains. However, much of the invertebrate community comprises obligate wetland organisms that are not derived from river channels, but instead spend dry seasons in moist soils or permanent lentic water...
Article
Full-text available
Intermittent rivers are naturally dynamic ecosystems in which flow cessation and riverbed drying cause temporal fluctuations in aquatic biodiversity. We analysed datasets from intermittent rivers in different climate zones across the world to examine responses of aquatic macroinvertebrate assemblages to drying, in relation to both taxonomic composi...
Article
Full-text available
1. Rivers and streams that do not flow permanently (herein intermittent rivers; IRs) make up a large proportion of the world's inland waters and are gaining widespread attention. We review the research on IRs from its early focus on natural history through to current application in management and policy. 2. The few early studies of the ecology of I...
Article
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Droughts are unpredictable disturbances characterized in streams by declining flow, reduced habitat availability, and deteriorating abiotic conditions. Such events typically reduce benthic invertebrate taxon richness and modify assemblage composition, but little is known about how hyporheic invertebrate assemblages respond to drought or how these r...
Article
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Environmental flow rules are developed to provide a flow regime necessary to maintain healthy river and floodplain ecosystems in rivers regulated for human uses. However, few studies have experimentally assessed potential ecological mechanisms causing declines in the health and productivity of freshwater fish assemblages in regulated rivers to info...
Article
Aim We tested the hypothesis that shredder detritivores, a key trophic guild in stream ecosystems, are more diverse at higher latitudes, which has important ecological implications in the face of potential biodiversity losses that are expected as a result of climate change. We also explored the dependence of local shredder diversity on the regional...
Article
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Most hypotheses explaining the general gradient of higher diversity toward the equator are implicit or explicit about greater species packing in the tropics. However, global patterns of diversity within guilds, including trophic guilds (i.e., groups of organisms that use similar food resources), are poorly known. We explored global diversity patter...
Article
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The decomposition of plant litter is one of the most important ecosystem processes in the biosphere and is particularly sensitive to climate warming. Aquatic ecosystems are well suited to studying warming effects on decomposition because the otherwise confounding influence of moisture is constant. By using a latitudinal temperature gradient in an u...
Data
Full-text available
The decomposition of plant litter is one of the most important ecosystem processes in the biosphere and is particularly sensitive to climate warming. Aquatic ecosystems are well suited to studying warming effects on decomposition because the otherwise confounding influence of moisture is constant. By using a latitudinal temperature gradient in an u...
Article
Full-text available
Many river restoration projects fail. Inadequate project planning underpins many of the reasons given for failure (such as setting overly ambitious goals; selecting inappropriate sites and techniques; losing stakeholder motivation; and neglecting to monitor, assess, and document projects). Another major problem is the lack of an agreed guiding imag...
Article
Current global models predict a hotter and drier climate in the southwestern United States with anticipated increases in drought frequency and severity coupled with changes in flash flood regimes. Such changes would likely have important ecological consequences, particularly for stream and riparian ecosystems already subject to frequent hydrologic...
Article
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Defining appropriate environmental flow regimes and criteria for the use of environmental water allocations requires experimental data on the ecological impacts of flow regime change and responses to environmental water allocation. Fish assemblages in one regulated and one unregulated tributary paired in each of two sub-catchments of the Hunter Riv...
Article
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The potential role of the hyporheic zone as a refugium for stream invertebrates during hydrological perturbations was acknowledged more than fi ve decades ago. However, field evidence to support the hyporheic refuge hypothesis during periods of fl ow recession and severe low flow remains equivocal. Some studies report fauna using the hyporheic zone...
Article
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Over the last 25 y, stream ecosystem theory has expanded to include explicitly the vertical dimension of surface–groundwater linkages via the hyporheic zone and below alluvial floodplains. Hydrological exchange between the stream and hyporheic zone mediates transport of products from the biogeochemical activities within the sediments. Hot-spots of...
Article
As demand for consumptive use of groundwater escalates, the need for careful management becomes more pressing. Water reforms in Australia require explicit recognition of environmental needs in water resource plans, but subsurface groundwater dependent ecosystems (SGDEs) are rarely provided for. The ecological values of these sequestered ecosystems...
Article
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Human demands for water reduce total discharge and extend the natural durations of low flows in streams and rivers worldwide. Although these 'artificial droughts' are predicted to increase, their ecological effects are poorly understood, hampering management of the timing and volume of extractions to minimise damage to stream ecosystems. This study...
Article
Full-text available
Despite the widely accepted importance of the hyporheic zone as a habitat for stream macroinvertebrates during floods, few data exist regarding community composition and distribution during periods of low flow or drought in perennial streams. Integrating research on hyporheic invertebrates with results from a long-term study of a UK river provided...
Article
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Exotic plants have invaded the riparian zones of many streams worldwide, but their consequences for stream fauna are seldom fully appreciated, especially when effects are sublethal. In northern New South Wales, Australia, the exotic tree camphor laurel (Cinnamomum camphora) has aggressively invaded riparian zones of many subtropical streams, often...
Article
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Summary1. Growing recognition of the ecological significance and biodiversity of groundwater fauna in Australia has led to statutory requirements for monitoring these communities prior to resource development. However, the efficiency of methods for assessing community composition and taxa richness remains untested, hampering the collection of relia...
Article
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The pervious lateral bars (parafluvial zone) and beds (hyporheic zone), where stream water and groundwater exchange, are dynamic sites of hydrological and biological retention. The significance of these biogeochemical 'hotspots' to stream and groundwater metabolism is largely controlled by filtration capacity, defined as the extent to which subsurf...
Article
Many river restoration projects seek to address issues associated with impaired hydrological and ecological connectivity in longitudinal (e.g. effects of dams, weirs) or lateral (e.g. alienated floodplain) dimensions. Efforts to restore the vertical dimension of impaired streamgroundwater exchange are rare, hampered by limited understanding of the...
Article
This chapter explores the evidence for and against the proposition that there are fundamental differences in the ecology of temperate and tropical streams. It reveals that despite considerable variability in geological history, flow regime, and geomorphology, streams in the tropics typically receive higher insolation and more intense rainfall, with...
Article
Global climate change scenarios predict more frequent and extended droughts, especially in the mid-latitudes. For many stream insects, these increasing periods of drought are likely to cause local if not regional extinctions, with potentially severe consequences for stream ecosystem function. Drought is a steadily-intensifying 'ramp' disturbance th...
Article
Full-text available
Worldwide, the ecological condition of streams and rivers has been impaired by agricultural practices such as broadscale modification of catchments, high nutrient and sediment inputs, loss of riparian vegetation, and altered hydrology. Typical responses include channel incision, excessive sedimentation, declining water quality, and loss of in-strea...
Article
Short-range endemism is common in groundwater fauna (stygofauna), placing many species at risk from anthropogenic impacts such as water abstraction and pollution. Few of the alluvial aquifers in eastern Australia have been sampled for stygofauna. Fauna from two aquifers in Queensland and two in New South Wales was sampled to improve ecological know...
Article
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Recent surveys of groundwater invertebrates (stygofauna) worldwide are yielding rich troves of biodiversity, with significant implications for invertebrate systematists and phylogeneticists as well as ecologists and groundwater managers. What is the ecological significance of this high biodiversity of invertebrates in some aquifers? How might it in...
Chapter
This book considers some of the potential influences on individuals and populations (e.g. environmental stresses, parasites, cannibalism, dispersal limitations), the 'cunning tricks' used by aquatic insects to overcome challenges (e.g. polarization vision, life-history strategies, osmoregulation, cold hardiness) and the consequences of those challe...
Article
Many streams of southwestern Australia have become secondarily saline through land clearance and other human activities in their catchments. Elevated salinities impact on aquatic biota and ecological processes of surface streams but little is known of the effects on the diversity and community composition of hyporheic (subsurface) invertebrates occ...
Article
Full-text available
Summary 1. Water extraction from arid-zone rivers increases the time between floods across their floodplain wetlands. Less frequent flooding in Australian arid-zone rivers has impaired waterbird and fish breeding, killed riparian vegetation and diminished invertebrate and mac- rophyte communities. Restoration currently focuses on reinstating floods...
Article
Summary1. The hyporheic zone below the channel and banks of many rivers where surface water and ground water exchanges plays a crucial functional role in the biogeochemical transformation of water, mediated by active microbial biofilms. This zone also harbours assemblages of invertebrates that graze biofilms, contribute to secondary production, and...
Article
Since European settlement, vast amounts of wood have been removed from Australian rivers. In recognition of its ecological value, including as habitat for aquatic invertebrates, wood is being reintroduced but with little understanding of optimum placement (pools v. riffles) or structural complexity to enhance invertebrate diversity. We hypothesised...
Article
Full-text available
Human impacts to aquatic ecosystems often involve changes in hydrologic connectivity and flow regime. Drawing upon examples in the literature and from our experience, we developed conceptual models and used simple bivariate plots to visualize human impacts and restoration efforts in terms of connectivity and flow dynamics. Human-induced changes in...
Article
1 Fine mesh (63 nm) traps filled with defaunated sediment and open to recolonization from upstream, downstream or below were buried 30 cm deep in the hyporheic zone of a gravel run in a desert stream and recovered after 1, 3, 7, 14 and 27 days. Temporal changes in organic matter and faunal composition and abundance were compared among treatments an...
Article
1. Amplitudes in physicochemical features in intermittent streams exceed those in nearby permanent streams and strongly influence macroinvertebrate community structure. Hitherto, seasonal variation in the physicochemistry of intermittent streams has been described only anecdotally; there has been no objective attempt to describe phases of flow that...
Article
1. We compared aquatic macroinvertebrate assemblage composition within and between habitats (pools and riffles) at four sites on two intermittent streams in Victoria, Australia during a drought year followed by a wetter year to see how different spatial and temporal scales influenced patterns of community structure detected by multivariate techniqu...
Article
Many rivers are classified as groundwater-dependent ecosystems (GDEs), owing to the contribution of groundwater to their base flow. However, there has been little explicit recognition of the way groundwater influences riverine biota or processes, how degrees of ecological dependency may vary, and the management implications of this dependency. The...
Article
Urbanization is acknowledged as one of the most severe threats to stream health, spawning recent research efforts into methods to ameliorate these negative impacts. Attention has focused on streams in densely-populated cities but less populous regional urban centres can be equally prone to some of the same threats yet might not meet the conventiona...
Article
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Wetlands in arid and semi-arid areas face intensifying pressure for their water resources yet harbour unique biota and ecological processes that rely on the “boom and bust” regime of alternating flood and drought. Recent research in Australia has revealed that models of ecosystem processes derived from northern temperate zone wetlands are often ina...
Article
1. To encourage more project assessment and reporting of restoration outcomes, Palmer et al. (2005) propose five criteria for assessing the ecological success of river restoration. They also suggest that these criteria should help to clarify which activities should qualify for ecological restoration funding and facilitate consistency about what con...