Holistic Ecosystem Approach Research Articles

Monitoring benthic habitats in English Marine Protected Areas: Lessons learned, challenges and future directions

Thousands of Marine Protected Areas (MPAs) have been designated around the globe to conserve benthic habitats, following the adoption of Convention on Biodiversity Aichi Target 11 and widespread endorsement of the ‘30by30’ initiative. When designed and managed effectively, MPAs can enrich biodiversity, enhance ecosystem services and regulate stakeholder access. High quality dedicated monitoring programmes are essential to determine MPA effectiveness at the correct spatial and temporal scales; however, such programmes can be fraught with complexities and many MPAs have not yet implemented them following designation. There is, therefore, a clear need and opportunity for scientists to share and draw on collective experiences to help reduce barriers to successful MPA monitoring. This study synthesises lessons learned and challenges encountered in the English MPA monitoring programme, reflecting on solutions and future directions. Twenty-three MPA monitoring reports were reviewed and the key findings were extracted. The majority were centred around the need to consider monitoring approaches at the scale of each individual MPA, rather than adoption of generic ‘one-size-fits-all’ practices. Various challenges were found to be inherent, whilst some were prioritised for further development: MPA-scale measures of condition, fishing activity data, seabed imagery acquisition and analysis, DNA technologies, habitat mapping, and ecosystem approaches to MPA monitoring. This study highlights the benefits of strong multi-disciplinary partnerships for addressing the complex issues encountered in MPA monitoring programmes. We endorse further studies, technical advancements and a more holistic ecosystem approach to understanding human impacts on the benthos, thus optimising MPA management and positive conservation outcomes.

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Conservation of the endangered Arctic fox in Norway - are successful reintroductions enough?

Translocation of captive-bred animals has become a widespread conservation practice to counteract species extinctions. We analyse and discuss the apparent success and shortcomings of Arctic fox (Vulpes lagopus) reintroductions in alpine tundra areas of Norway. We followed the fate of 915 foxes between 2007 and 2020 and estimated the apparent survival and reproductive success of captive-bred and released Arctic foxes, compared to wild-born descendants. Relationship to abundance of small rodents, population size, and age were explored. Overall, apparent survival and probability of breeding were similar between captive-bred and wild-born foxes, positively linked to rodent abundance. For wild-born foxes, both breeding propensity and litter size declined with increasing fox population size. This could be a first sign of the limited capacity of single tundra patches to house self-subsistent populations. Thus, facilitating and maintaining connectivity among remnant and re-established Arctic fox populations, creating functional metapopulations, is essential for further improvement and long-term survival. Relying on the combined measures of supplementary feeding and red-fox (Vulpes vulpes) control, the Arctic fox captive-breeding and reintroduction programme has so far been highly successful. However, anthropogenic drivers facilitating red fox invasion into the Arctic fox habitat, along with climate driven irregularities and dampened small rodent cycles, could inhibit the establishment of a self-sustained population. A more holistic ecosystem approach and conservation measures to restore alpine fauna should be considered.

A system of marine animal bioconstructions in the mesophotic zone along the Southeastern Italian coast

A widespread and diversified mesophotic system of carbonate bioconstructions along the Southern Adriatic and Ionian Italian coasts is described, providing new data on the distribution, structure and associated megabenthic assemblages of mesophotic Mediterranean bioconstructions. The bioconstructions were detected at six different sites off the coasts of Apulia, in presence of marked morphological escarpments, developing on a basal substrate consisting of meso-Cenozoic carbonate rocks. Two biogenic structure types were observed, one mainly built by the nonsymbiotic scleractinians Phyllangia americana mouchezii and Polycyathus muellerae, at depths between approximately 35 and 55 m, and the other by the oyster Neopycnodonte cochlear, at depths from approximately 40 to 70 m. A total of 52 taxa of megabenthic invertebrates, belonging to 6 phyla, were found on the surface of the mesophotic bioconstructions, thus confirming the role of biodiversity hotspots of these carbonate structures. Megabenthic assemblages showed a remarkable heterogeneity both in pattern of species and abundance, probably depending on both the morphological differences of the seabed and the life traits of the single species. Primary bioconstructors seemed to influence the associated community pattern. This peculiar system deserves sound conservation measures in the light of the holistic ecosystem approach for the management of coastal marine areas.

Addressing the Early-Successional Habitat Needs of At-Risk Species on Privately Owned Lands in the Eastern United States

Public lands alone are insufficient to address the needs of most at-risk wildlife species in the U.S. As a result, a variety of voluntary incentive programs have emerged to recruit private landowners into conservation efforts that restore and manage the habitats needed by specific species. We review the role of one such effort, Working Lands for Wildlife (WLFW), initiated by the Natural Resources Conservation Service in partnership with the U.S. Fish and Wildlife Service. Using two at-risk species in the eastern U.S. (where private lands dominate), we show the substantial potential that WLFW has for restoring and maintaining needed habitats. Monitoring how effective these efforts are on populations of the target species has been challenging, and both monitoring and implementation are being modified in response to new information. Identifying landowner motivations is essential for developing long-term relationships and conservation success. As WLFW projects develop, they are moving toward a more holistic ecosystem approach, within which the conservation goals of at-risk species are embedded.

Associations of health status and diabetes among First Nations Peoples living on-reserve in Canada

ObjectiveOur objective is to describe self-reported health status, prevalence of diabetes and obesity and their associations in participants from the First Nations Food, Nutrition and Environment Study (FNFNES) in order to identify possible correlates of health in First Nations adults.MethodsFNFNES is a participatory study with First Nations Peoples living on reserve lands south of the 60th parallel. Health and diabetes were self-reported, and prevalence of obesity was evaluated. Socio-demographic and lifestyle factors and traditional food (TF) activities were investigated for associations with health parameters.ResultsHigh prevalence rates of overweight/obesity (78–91%) and diabetes (19% age-standardized prevalence) were found. Smoking rates were high and physical activity was low. In multivariable analyses, obesity was associated with region, income source, age, gender, smoking and self-reported health; diabetes and lesser self-reported health were associated with obesity and lower education. Diabetes was strongly associated with lesser self-reported health and weakly associated with being a smoker.ConclusionWe have identified possible correlates of health in this population that can help to better understand the underlying concerns and identify solutions for First Nations and their partners. We urge governments and First Nations to address the systemic problems identified with a holistic ecosystem approach that takes into consideration the financial and physical access to food, particularly TF, and the facilitation of improved health behaviour. New mechanisms co-developed with First Nations leadership should focus on supporting sustainable, culturally safe and healthy lifestyles and closing the gaps in nutrition and food insecurity.

Emerging trends in government venture capital policies in smaller peripheral economies: Lessons from Finland, New Zealand, and Estonia

AbstractEmerging trends from the developing venture capital industries of three smaller peripheral economies (Finland, New Zealand, and Estonia), demonstrate that government policy can overcome scale and distance barriers to assist in establishing venture capital to support innovative potential high growth ventures. Eight common policy themes for successful venture capital development are: new venture stimulation; dedicated finance policy institutions; stable, internationally harmonized tax and regulations; business angel development; inward investment; international venture capital fund development; smooth pipeline of investment; effective investment exit market. Venture capital policy development themes are interconnected, requiring a holistic ecosystem approach. A blueprint for successful small peripheral economy venture capital development requires an initial phase of new venture demand stimulation and ensuing simultaneity of policies to engineer venture capital development.

International Whale Conservation in a Changing Climate: The Ecosystem Approach, Marine Protected Areas, and the International Whaling Commission

Whale populations are exposed to a suite of contemporary threats, including by-catch, ship strikes, habitat degradation, and climate change. Of these threats, climate change presents the most challenging management dilemma because it pressures whale populations directly (e.g., by altering habitat suitability) and indirectly (e.g., by increasing disease transmission and exposure to toxicants, by affecting prey abundance, and by exacerbating other threats). There is also an emerging scientific understanding of how healthy whale populations constitute an important biological component of the climate system and contribute to climate change mitigation. The International Whaling Commission (“IWC”), which is the primary international organization dedicated to whale conservation and management, has investigated and studied climate change but has failed to develop a commensurate management response. Conversely, parallel developments in international wildlife conservation and management evince support for an integrated and holistic ecosystem approach (“EA”) and urge the immediate development of climate-adaptive measures. The EA has been operationalized in prominent legal instruments and through various management techniques, including marine protected areas (“MPAs”). In view of observed and predicted effects of climate change on whales, this article proposes a new approach to designating and protecting whale sanctuaries at the IWC that better aligns with a contemporary understanding of the EA and MPAs, and that can advance the IWC’s institutional transition towards climate-informed modernized management. This proposed innovation is tested for its legal permissibility and political feasibility, and the analysis concludes that improving the IWC’s regulatory functionality remains a crucial conservation objective.

Analysing the take up of battery electric vehicles: An investigation of barriers amongst drivers in the UK

The stream of announcements in 2017, effectively banning the production and sales of internal combustion engine vehicles within the next fifteen-twenty years, indicate how governments are seeking to regulate a mass market transition to electric vehicles. Yet despite significant policy initiatives to stimulate their uptake, EV market share remains far short of the level required to push them into the mainstream. This paper identifies a multitude of potential barriers to uptake and investigates these from the largely ignored perspective of mass market drivers of ICE vehicles in a European context. In addition it assesses the extent to which barriers are inter-related, and can be reduced down to larger explanatory ‘factors’. Findings, drawn from an original survey of 26,000 motorists suggest that resistance to EV adoption is characterised by twelve barriers that can be reduced and conceptualised as ‘economic uncertainty’ and ‘socio-technical’ factors. In turn, economic uncertainty was found to be significantly associated with age and geography, whilst socio-technical issues are related to gender. Problems of EV adoption are shown to be complex and multi-faceted, not easily solved by tackling individual issues, but requiring a more holistic ecosystem approach, the key policy components of which are posited in this paper. Such analysis is significant in enriching academic discourse and informing effective strategy and policy that will facilitate the transition to EVs.

СЬОМА ЕКОЛОГІЧНА ПРОГРАМА ЄС: ЛАНДШАФТИ ЯК ОБ'ЄКТ ПРАВОВОГО РЕГУЛЮВАННЯ ЧИ ЕЛЕМЕНТ «ПРИРОДНОГО КАПІТАЛУ»

The article reviews the key norms of the EU Seventh Environmental Program in the aspect of sustainable development policy, planning of legal regulation of the use and protection of certain types of natural resources and landscapes in particular. The author analyzes the legislative base and the significance of individual acts for the preservation of the natural capital of the European Union, the neighboring countries and the world’s resources in general. Data on the degree of implementation of EU plans and strategies for reducing the negative impact of human activities on the environment and on the possible consequences and damage due to delays in their implementation are given. The author underlines the importance of a holistic ecosystem approach to the use and protection of natural capital. Keywords: the seventh EU environmental program, sustainable development, environmental planning, landscape, ecosystem approach, natural capital.

The drivers of sea lice management policies and how best to integrate them into a risk management strategy: An ecosystem approach to sea lice management.

The control of sea lice infestations on cultivated Atlantic salmon is a major issue in many regions of the world. The numerous drivers which shape the priorities and objectives of the control strategies vary for different regions/jurisdictions. These range from the animal welfare and economic priorities of the producers, to the mitigation of any potential impacts on wild stocks. Veterinary ethics, environmental impacts of therapeutants, and impacts for organic certification of the produce are, amongst others, additional sets of factors which should be considered. Current best practice in both EU and international environmental law advocates a holistic ecosystem approach to assessment of impacts and risks. The issues of biosecurity and ethics, including the impacts on the stocks of species used as cleaner fish, are areas for inclusion in such a holistic ecosystem assessment. The Drivers, Pressures, State, Impacts, Responses (DPSIR) process is examined as a decision-making framework and potential applications to sea lice management are outlined. It is argued that this is required to underpin any integrated sea lice management (ISLM) strategy to balance pressures and outcomes and ensure a holistic approach to managing the issue of sea lice infestations on farmed stock on a medium to long-term basis.

An Overview of the Current Status of Lake Naivasha Fishery: Challenges and Management Strategies

Lake Naivasha a shallow, freshwater body and a Ramsar site is found in the eastern arm of the Kenyan Rift Valley. This paper used published, unpublished and analyzed data to assess the status, challenges and management options for the fishery. Lake Naivasha fishery is based on exotic species that fluctuates depending on fishing regime, lake water level and aquatic plant concentrations. The fishery has been dominated by different species with the current catch contribution consisting mainly of common carp, Cyprinus carpio, Nile tilapia, Oreochromis niloticus, blue-spotted tilapia, O. leucostictus and African catfish, Clarias gariepinus. The minimum and maximum catch of 21 t yr-1 and 1181 t yr-1 was reported in 1997 and 2015, respectively. The main threats to the lake fishery are anthropogenic influences emanating from within the lake and its basin. The factors include intense fishing, exotic species introductions, water abstraction, lake level fluctuations, wetland utilization, eutrophication, and land degradation. There are also several conflicts of interest amongst the stakeholders in agriculture, fisheries, wildlife, tourism, conservation and geothermal electricity generation. There is fear that if the current trend persists, the lake and its fishery may be headed for extinction. The management measures instituted in the lake do not seem to have arrested reduction in fish catches nor reversed deterioration in water quality. For sustainable utilization of Lake Naivasha and its fishery, there is a need to consider a holistic ecosystem approach of the basin management. Additionally, all the relevant stakeholders should be involved in formulation and implementation of the decisions to manage the fishery.

The Continuous Plankton Recorder survey: How can long-term phytoplankton datasets contribute to the assessment of Good Environmental Status?

Phytoplankton are crucial to marine ecosystem functioning and are important indicators of environmental change. Phytoplankton data are also essential for informing management and policy, particularly in supporting the new generation of marine legislative drivers, which take a holistic ecosystem approach to management. The Marine Strategy Framework Directive (MSFD) seeks to achieve Good Environmental Status (GES) of European seas through the implementation of such a management approach. This is a regional scale directive which recognises the importance of plankton communities in marine ecosystems; plankton data at the appropriate spatial, temporal and taxonomic scales are therefore required for implementation. The Continuous Plankton Recorder (CPR) survey is a multidecadal, North Atlantic–basin scale programme which routinely records approximately 300 phytoplankton taxa. Because of these attributes, the survey plays a key role in the implementation of the MSFD and the assessment of GES in the Northeast Atlantic region. This paper addresses the role of the CPR's phytoplankton time-series in delivering GES through the development and informing of MSFD indicators, the setting of targets against a background of climate change and the provision of supporting information used to interpret change in non-plankton indicators. We also discuss CPR data in the context of other phytoplankton data types that may contribute to GES, as well as explore future possibilities for the use of new and innovative applications of CPR phytoplankton datasets in delivering GES. Efforts must be made to preserve long-term time series, such as the CPR, which supply vital ecological information used to informed evidence-based environmental policy.

Recovery of Danish Coastal Ecosystems After Reductions in Nutrient Loading: A Holistic Ecosystem Approach

In the 1980s, Danish coastal waters suffered from eutrophication and several nutrient management plans have been implemented during the years to improve ecological status. This study aims at giving a holistic ecosystem perspective on 25 years of mitigation measures. We report trends of nutrient inputs and the responses to these in various chemical and biological components. Nutrient inputs from land were reduced by ~50 % for nitrogen (N) and 56 % for phosphorus (P) since 1990. These reductions resulted in significant and parallel declines in nutrient concentrations, and initiated a shift in the dominance of primary producers towards reduced phytoplankton biomass (chlorophyll a concentration) and increased cover of macroalgae in deeper waters. In the last 5 years, eelgrass meadows have also expanded towards deeper waters, in response to improving water clarity. An expected improvement of bottom water oxygen conditions has not been observed, presumably because more frequent stratification and higher water temperatures have counteracted the expected positive effects of reduced nutrient inputs. The biomass of the benthic macrofauna decreased as expected, but it was composed of a drastic decline of filter feeders paralleled by a more moderate increase of deposit feeders. This shift was most likely induced by increasing stratification. The reduced benthic filtration along with the limited eelgrass cover probably kept relatively more particles in suspension, which can explain why improvements in the Secchi depths were modest. Overall, several ecosystem components demonstrated clear signs of improvement, suggesting that at least partial recovery is attainable. On this basis, we propose a conceptual scheme for recovery of shallow coastal ecosystems following marked reductions in nutrient inputs.

The effect of psychological violence in the workplace on health: A holistic eco-system approach

Background: Psychological violence has emerged as a priority concern in all workplaces because of its adverse consequences on victims’ health. So far, limited research has been conducted on the effect of psychological violence on the five interrelated contexts of human existence.Objectives: This qualitative study investigated the perceived effect of psychological violence in the workplace on staff members’ holistic health at a multi-campus South African Further Education and Training College. By investigating the effect of psychological violence on these five interrelated contexts, the resultant effect on holistic health might be more fully understood and applicable recommendations formulated to ameliorate the perceived effects.Method: A qualitative, exploratory and descriptive research design was used to investigate the perceived effect of psychological violence on staff members’ health. Purposeful sampling was used to select 29 participants to be interviewed individually, based on their experiences of psychological violence, as well as data saturation. The researcher analysed the data and a co-coder cross-checked the codes.Results: The results pertaining to the perceived effects of psychological violence were positioned within the holistic eco-systemic approach as encompassing theory. Five themes were identified accordingly after data analysis, namely, psychological, biophysical, spiritual, ecological and metaphysical effects.Conclusion: Findings revealed that psychological violence impacts adversely on all five interrelated contexts of individual health, leading to an adverse cumulative effect on staff members’ holistic health and on the systems in which psychological violence occurs. Based on the findings, recommendations could be made to ameliorate the perceived adverse effect of psychological violence. Agtergrond: Psigologiese geweld is tans besig om op die voorgrond te tree as ’n prioriteit in alle werksplekke as gevolg van die ernstige nadelige gevolge daarvan op die gesondheid van slagoffers. Tot dusver is beperkte navorsing gedoen rakende die effek van psigologiese geweld op die vyf interverwante kontekste van menslike bestaan.Doelwitte: Hierdie kwalitatiewe studie het die waargenome effek van psigologiese geweld in die werksplek op die holistiese gesondheid van personeellede in ʼn multi-kampus Verdere Onderwys en Opleiding Kollege ondersoek. Deur die effek van psigologiese geweld op hierdie vyf interverwante kontekste te ondersoek, kon die gevolglike effek op holistiese gesondheid; meer volledig verstaan word en toepaslike aanbevelings geformuleer word om die waargenome effek te verbeter.Metode: ’n Kwalitatiewe, verkennende en beskrywende navorsingsontwerp is gebruik om die waargenome effek van psigologiese geweld op personeellede se gesondheid te ondersoek. ’n Doelgerigte steekproef is gebruik om 29 deelnemers te selekteer om indivuele onderhoude mee te voer, gebaseer op hul ervarings van psigologiese geweld, asook data versadiging. Die navorser het die data geanaliseer en ’n mede-kodeerder het die kodes kruis-kodeer.Resultate: Die resultate rakende die waargenome effek van psigologiese geweld was geposisioneer binne die holisties eko-sistemies benadering as omvattende teorie. Vyf temas is dienoorkeenkomstig na afloop van die data-anelisering geidentifiseer naamlik psigologiese, biofisiese, spirituele, ekologiese en metafiese effekte.Gevolgtrekking: Bevindings het aangetoon dat psigologiese geweld ’n negatiewe impak het of al vyf interverwante kontekste van individuele gesondheid wat lei tot ’n negatiewe kumulatiewe effek op personeellede se holistiese gesondheid in die sisteme waar psigologiese geweld plaasvind. Aanbevelings, gebaseer op die bevindinge, kon gemaak word om die nadelige effek van psigologiese geweld te verbeter.

Should conservation of biodiversity involve private land? A Q methodological study in Poland to assess stakeholders’ attitude

Biodiversity conservation is gradually shifting its dependency on public protected areas to take a more holistic ecosystem and landscape approach that includes private lands in addition to public lands. However, effective practice of biodiversity conservation on private land also depends on landowners’ attitude and their willingness to participate and cooperate. This study focuses on Poland where conservation on private land is a relatively new concept but it is slowly gaining recognition, especially after its accession into the European Union. It investigates and classifies the diverse attitudes among stakeholder groups in Poland toward biodiversity conservation on private land that are part of protected areas. Four primary stakeholder groups were considered: conservation and park authorities, local administrative officials, local conservation based NGOs and private landowners. The study was conducted across three sites that represented three different forms of protected areas in Poland: a national park, a landscape park and a Natura 2000 site. Q methodology, a research method from psychology and other social sciences, was used to classify human subjectivity in stakeholders’ attitude in a more systematic manner. The analysis yielded three predominant factors which highlighted the diversity in attitudes among the stakeholder groups based on their knowledge, concerns and experience in the subject. Additionally, it underlined the common recognition among all stakeholder groups for better policy support, stronger collaboration among stakeholder and more financial or compensatory support for landowners to make private land conservation more feasible. Understanding the differences in attitudes will help bridge the gap between conservation priority and conservation opportunity—a current challenge in the field of biodiversity conservation.

Consequences of More Intensive Forestry for the Sustainable Management of Forest Soils and Waters

Additions of nutrients, faster growing tree varieties, more intense harvest practices, and a changing climate all have the potential to increase forest production in Sweden, thereby mitigating climate change through carbon sequestration and fossil fuel substitution. However, the effects of management strategies for increased biomass production on soil resources and water quality at landscape scales are inadequately understood. Key knowledge gaps also remain regarding the sustainability of shorter rotation periods and more intensive biomass harvests. This includes effects of fertilization on the long-term weathering and supply of base cations and the consequences of changing mineral availability for future forest production. Furthermore, because soils and surface waters are closely connected, management efforts in the terrestrial landscape will potentially have consequences for water quality and the ecology of streams, rivers, and lakes. Here, we review and discuss some of the most pertinent questions related to how increased forest biomass production in Sweden could affect soils and surface waters, and how contemporary forestry goals can be met while minimizing the loss of other ecosystem services. We suggest that the development of management plans to promote the sustainable use of soil resources and water quality, while maximizing biomass production, will require a holistic ecosystem approach that is placed within a broader landscape perspective.

Unsuitability of TAC management within an ecosystem approach to fisheries: An ecological perspective

Fisheries management in European waters is gradually moving from a single-species perspective towards a more holistic ecosystem approach to management (EAM), acknowledging the need to take all ecosystem components into account. Prerequisite within an EAM is the need for management processes that directly influence the ecological effects of fishing, such as the mortality of target and non-target species. Up until recently, placing limits on the quantities of fish that can be landed, through the imposition of annual total allowable catches (TACs) for the target species, has been the principal management mechanism employed. However, pressure on non-target components of marine ecosystems is more closely linked to prevailing levels of fishing activity, so only if TACs are closely related to subsequent fishing effort will TAC management serve to control the broader ecosystem impacts of fishing. We show that in the mixed fisheries that characterise the North Sea, the linkage between variation in TAC and the resulting fishing effort is in fact generally weak. Reliance solely on TACs to regulate fishing activity is therefore unlikely to mitigate the impacts of fishing on non-target species. Consequently, we conclude that the relationship between TACs and effort is insufficient for TACs to be used as the principal management tool within an EAM. The implications, and some alternatives, for fisheries management are discussed.

Integrating Science and Society through Long-Term Socio-Ecological Research

Long-term ecological research (LTER), addressing problems that encompass decadal or longer time frames, began as a formal term and program in the United States in 1980. While longterm ecological studies and observation began as early as the 1400s and 1800s in Asia and Europe, respectively, the long-term approach was not formalized until the establishment of the U.S. long-term ecological research programs. These programs permitted ecosystem-level experiments and cross-site comparisons that led to insights into the biosphere’s structure and function. The holistic ecosystem approach of this initiative also allowed the incorporation of the human-dimension of ecology and recently has given rise to a new concept of long-term socio-ecological research (LTSER). Today, long-term ecological research programs exist in at least thirty-two countries (i.e., members of the International Long-Term Ecological Research Network, ILTER). However, consolidation of the international network within the long-term socio-ecological research paradigm still requires: (1) inclusion of certain remote regions of the world, such as southwestern South America, that are still poorly represented; (2) modifications of the type of research conducted, such as integrating social and natural sciences with the humanities and ethics; and (3) the incorporation of findings and results into broader social and political processes. In this context, a nascent long-term socio-ecological research network in Chile, which extends over the longest latitudinal range of temperate forest in the Southern Hemisphere, adds a new remote region to international long-term ecological research previously overlooked. In addition, collaboration with the University of North Texas and other international partners helps to further develop an interdisciplinary approach for the integration of the ecological sciences and environmental philosophy together with traditional ecological knowledge, informal and formal education, policy, the humanities, socio-political processes, and biocultural conservation.

Macrophyte growth and sediment phosphorus and nitrogen in a Canadian prairie river

1. The role of sediment phosphorus (P) and nitrogen (N) in regulating growth of rooted macrophytes in a Canadian prairie river was investigated by means of in situ observations and artificial stream fertilization experiments.2. Biomass and percentage cover of rooted macrophytes in the South Saskatchewan River increased downstream of a municipal sewage treatment plant, with maximum abundance occurring between 25 and 100 km downstream of the outfall. Biomass in the river was related to sediment P but not N concentration, although sites of maximum biomass did not coincide with sites of maximum sediment P concentration.3. Artificial stream experiments revealed that while biomass was unaffected by addition of N to the sediment, it was enhanced by the addition of P to sediments, and further enhanced with the addition of N and P together, indicating a primarily P‐limited system, with secondary N limitation when P is in excess.4. Macrophyte biomass increased linearly with increasing sediment P concentration in the artificial streams, and tissue P concentration peaked at ≈ 400 μg g–1. Biomass did not respond to increasing sediment N concentration, and only a weak relationship was observed between tissue N and sediment N, with maximum tissue N corresponding to ≈ 140 μg g–1 sediment exchangeable N.5. A lack of concurrence between the sediment P concentration producing maximum biomass and tissue P concentration in situ vs. under experimental conditions indicates that other environmental factors have an important role in regulating macrophyte growth in rivers. Thus, while nutrient control may be one element in a river macrophyte control programme, a holistic ecosystem approach should be adopted to account for the other factors that may affect the growth of rooted plants.