A function-based typology for Earth's ecosystems.

As the United Nations develops a post-2020 global biodiversity framework for the Convention on Biological Diversity, attention is focusing on how new goals and targets for ecosystem conservation might serve its vision of 'living in harmony with nature'1,2. Advancing dual imperatives to conserve biodiversity and sustain ecosystem services requires reliable and resilient generalizations and predictions about ecosystem responses to environmental change and management3. Ecosystems vary in their biota4, service provision5 and relative exposure to risks6, yet there is no globally consistent classification of ecosystems that reflects functional responses to change and management. This hampers progress on developing conservation targets and sustainability goals. Here we present the International Union for Conservation of Nature (IUCN) Global Ecosystem Typology, a conceptually robust, scalable, spatially explicit approach for generalizations and predictions about functions, biota, risks and management remedies across the entire biosphere. The outcome of a major cross-disciplinary collaboration, this novel framework places all of Earth's ecosystems into a unifying theoretical context to guide the transformation of ecosystem policy and management from global to local scales. This new information infrastructure will support knowledge transfer for ecosystem-specific management and restoration, globally standardized ecosystem risk assessments, natural capital accounting and progress on the post-2020 global biodiversity framework.

Wild longnose dace downstream of wastewater treatment plants display an obese phenotype.

Wild fish living downstream of wastewater treatment plants (WWTPs) often have increased body condition factors or body mass indices compared to upstream fish. This observation has been largely attributed to increased nutrient loading and food availability around wastewater effluent outflows. While a higher condition factor in fish is generally considered a predictor of healthy ecosystems, the metabolic status and capacity of the animals downstream of WWTPs may be a better predictor of fitness and potential population level effects. To address this, we sampled wild longnose dace (Rhinichthys cataractae), a native species in North American waterways, from sites upstream and downstream of WWTPs. Downstream fish had higher body mass indices, which corresponded with higher nutrient (lipid, protein, and glycogen) storage in somatic tissues compared to upstream fish. Liver transcriptome analysis revealed metabolic reprogramming favoring lipid synthesis, including higher hepatic triglyceride levels and transcript abundance of targeted lipogenic genes. This suggests that effluent exposure-mediated obesity in dace is a result of changes at the transcriptional level. To determine potential ecological consequences, we subjected these fish to an acute stressor in situ to determine their stress performance. Downstream fish failed to mobilize metabolites post-stress, and showed a reduction in liver aerobic and anaerobic metabolic capacity. Taken together, fish living downstream of WWTPs exhibit a greater lipid accumulation that results in metabolic disruption and may compromise the ability of these fish to cope with subsequent environmental and/or anthropogenic stressors.

Acute stress response of fathead minnows caged downstream of municipal wastewater treatment plants in the Bow River, Calgary.

We examined whether exposure to municipal wastewater effluent (MWWE) compromised the stress performance of laboratory-reared fathead minnows (Pimephales promelas) in a field setting. Adult minnows were caged at two sites upstream and three sites downstream of wastewater treatments plants (WWTPs) discharging MWWE into the Bow River, Calgary, Alberta, Canada. At each site one group of fish was sampled after a 26 day exposure to MWWE, while another group was subjected to 1-min air exposure followed by 60-min confinement and then sampled. Fish morphometrics and proximate composition were measured, and whole-body cortisol, glucose and lactate levels assessed as markers of the stress response. The whole-body protein, glycogen and lipid content were higher at the site closest to a WWTP outfall relative to the other downstream and upstream sites. There were no significant differences in whole-body cortisol levels in minnows sampled at sites either upstream or downstream of WWTPs. Acute stressor exposure significantly elevated whole-body cortisol levels in all groups, and this response was not modified by the location of the sampling sites. The whole-body metabolite profile, including glucose and lactate levels, were significantly higher in fish caged immediately downstream from WWTP inputs relative to upstream sites. There was an acute-stressor-mediated increase in whole-body lactate, but not glucose, levels and this response was independent of sampling site. The results reveal that the capacity to evoke an acute stress response was not compromised in fathead minnows caged for 26 days downstream of WWTPs in the Bow River. However, there were changes in the whole-body proximate composition and metabolite levels immediately downstream from the WWTP outfall suggesting greater accumulation of energy stores in these fish. Taken together, our results suggest that environmental factors in addition to contaminants, including higher water temperature and nutrient availability, influence the impact of MWWEs on fish stress performance.

The evolution of the major histocompatibility complex in upstream versus downstream river populations of the longnose dace.

Populations in upstream versus downstream river locations can be exposed to vastly different environmental and ecological conditions and can thus harbor different genetic resources due to selection and neutral processes. An interesting question is how upstream-downstream directionality in rivers affects the evolution of immune response genes. We used next-generation amplicon sequencing to identify eight alleles of the major histocompatibility complex (MHC) class II ß exon 2 in the cyprinid longnose dace (Rhinichthys cataractae) from three rivers in Alberta, upstream and downstream of municipal and agricultural areas along contaminant gradients. We used these data to test for directional and balancing selection on the MHC. We also genotyped microsatellite loci to examine neutral population processes in this system. We found evidence for balancing selection on the MHC in the form of increased nonsynonymous variation relative to neutral expectations, and selection occurred at more amino acid residues upstream than downstream in two rivers. We found this pattern despite no population structure or isolation by distance, based on microsatellite data, at these sites. Overall, our results suggest that MHC evolution is driven by upstream-downstream directionality in fish inhabiting this system.

Asynchronous onset of eutrophication among shallow prairie lakes of the Northern Great Plains, Alberta, Canada.

Coherent timing of agricultural expansion, fertilizer application, atmospheric nutrient deposition, and accelerated global warming is expected to promote synchronous fertilization of regional surface waters and coherent development of algal blooms and lake eutrophication. While broad-scale cyanobacterial expansion is evident in global meta-analyses, little is known of whether lakes in discrete catchments within a common lake district also exhibit coherent water quality degradation through anthropogenic forcing. Consequently, the primary goal of this study was to determine whether agricultural development since ca. 1900, accelerated use of fertilizer since 1960, atmospheric deposition of reactive N, or regional climate warming has resulted in coherent patterns of eutrophication of surface waters in southern Alberta, Canada. Unexpectedly, analysis of sedimentary pigments as an index of changes in total algal abundance since ca. 1850 revealed that while total algal abundance (as ß-carotene, pheophytin a) increased in nine of 10 lakes over 150 years, the onset of eutrophication varied by a century and was asynchronous across basins. Similarly, analysis of temporal sequences with least-squares regression revealed that the relative abundance of cyanobacteria (echinenone) either decreased or did not change significantly in eight of the lakes since ca. 1850, whereas purple sulfur bacteria (as okenone) increased significantly in seven study sites. These patterns are consistent with the catchment filter hypothesis, which posits that lakes exhibit unique responses to common forcing associated with the influx of mass as water, nutrients, or particles.

Environmental contaminant mixtures at ambient concentrations invoke a metabolic stress response in goldfish not predicted from exposure to individual compounds alone.

Environmental contaminants from wastewater and industrial or agricultural areas are known to have adverse effects on development, reproduction, and metabolism. However, reliable assessment of environmental contaminant impact at low (i.e., ambient) concentrations using genomics and transcriptomics approaches has proven challenging. A goldfish model was used to investigate the effects of aquatic pollutant exposure in vivo by means of quantitative nuclear magnetic resonance metabolomics in multiple organs to elucidate a system-wide response. Animals were exposed to 4,4'-isopropylidenediphenol (Bisphenol-A, BPA), di-(2-ethylhexyl)-phthalate (DEHP), and nonylphenol (NP). Metabolite-specific spectral analysis combined with pathway-driven bioinformatics indicated changes in energy and lipid metabolism in liver following exposure to individual contaminants and a tertiary mixture. A dissimilar response in testis exposed to DEHP and mixture indicates disrupted AMPK and cAMP signaling. Uniquely, our observations (1) suggest that exposure to a contaminant mixture is characterized by a stress response not predicted from exposure to individual contaminants, even in the absence of other phenotypic features and (2) demonstrate the sensitivity of metabolomics in risk-assessment of environmental toxicant mixtures at ambient concentrations by detecting early stage metabolic dysregulation. These findings have general applicability in the assessment of "benign" compound mixtures in environmental and pharmaceutical development.

Feminization of Longnose Dace (Rhinichthys cataractae) in the Oldman River, Alberta, (Canada) Provides Evidence of Widespread Endocrine Disruption in an Agricultural Basin.

We sampled an abundant, native minnow (Longnose dace-Rhinichthys cataractae) throughout the Oldman River, Alberta, to determine physiological responses and possible population level consequences from exposure to compounds with hormone-like activity. Sex ratios varied between sites, were female-biased, and ranged from just over 50% to almost 90%. Histological examination of gonads revealed that at the sites with >60% females in the adult population, there was up to 38% occurrence of intersex gonads in fish identified through visual examination of the gonads as male. In the majority of intersex gonad cases, there was a large proportion (approx., 50%) of oocytes within the testicular tissue. In male dace, vitellogenin mRNA expression generally increased with distance downstream. We analyzed river water for 28 endocrine disrupting compounds from eight functional classes, most with confirmed estrogen-like activity, including synthetic estrogens and hormone therapy drugs characteristic of municipal wastewater effluent, plus natural hormones and veterinary pharmaceuticals characteristic of livestock production. The spatial correlation between detected chemical residues and effects to dace physiology indicate that multiple land uses have a cumulative impact on dace in the Oldman River and effects range from altered gene regulation to severely female-biased sex ratios.

Presence of natural and anthropogenic organic contaminants and potential fish health impacts along two river gradients in Alberta, Canada.

In the current study, 28 organic contaminants were measured, many with estrogen-like activity, in water collected from 16 sites on two rivers in the South Saskatchewan River Basin, Alberta, Canada. The compounds detected included synthetic estrogens (birth control pill compounds and hormone therapy drugs) downstream of municipal wastewater effluents and natural hormones downstream of municipal wastewater effluents and in agricultural areas. Greater concentrations of cholesterol and derivatives, phytosterols, and fecal sterols were measured at the most downstream sites, which indicates cumulative inputs of such compounds in these rivers. A native minnow (longnose dace, Rhinichthys cataractae) was sampled to assess pathophysiological responses to exposure to compounds with estrogen-like activity. Hepatic vitellogenin protein was detected in at least one adult male longnose dace from 14 of 15 sites sampled for fish. Vitellogenin was negatively correlated with hepatosomatic (r = -0.47, p < 0.001) and gonadosomatic (r = -0.44, p < 0.003) indices, which suggests potential health impacts in male longnose dace in the South Saskatchewan River Basin. The current study demonstrates that organic contaminants, many with estrogen-like activity, are distributed over hundreds of kilometers throughout the South Saskatchewan River Basin and not just downstream of major point-sources. Therefore, many activities within these basins impact water quality in the South Saskatchewan River Basin and affect endemic longnose dace populations.

Basin-wide impacts of compounds with estrogen-like activity on longnose dace (Rhinichthys cataractae) in two prairie rivers of Alberta, Canada.

Environmental compounds with estrogen- or antiestrogen-like activity can enter rivers from multiple sources, including municipal wastewater and agricultural runoff. We used longnose dace (Rhinichthys cataractae) to investigate exposure to compounds with estrogen-like activity, which we measured in water at multiple sites in the Oldman and Bow rivers (AB, Canada). We evaluated changes in vitellogenin mRNA with quantitative reverse transcription-polymerase chain reaction, then compared vitellogenin levels to sex ratios and fish performance indices to assess how exposure to compounds with estrogen-like activity affects longnose dace populations. Vitellogenin levels were elevated at least 59 to 110 km downstream of municipalities. In the Oldman River, increased vitellogenin expression and female-biased sex ratios suggest severe endocrine disruption, likely resulting from the combined impacts of municipal wastewater, agriculture, and large cattle operations within the basin. In the Bow River, municipal wastewater may be the major source of compounds with estrogen-like activity that affect longnose dace. The sex ratios were not heavily skewed, as in the more agriculturally influenced Oldman River. We detected organic contaminants in river samples at every site, but the highest concentrations were found downstream of municipalities and in areas with intense agriculture. Vitellogenin levels and sex ratios of longnose dace suggest basin-wide exposure to compounds with estrogen-like activity. Our results demonstrate that it is important to assess rivers at large spatial scales to detect fully the impacts of municipal wastewater and agriculture on fish populations.

Changes in population, growth, and physiological indices of Longnose dace (Rhinichthys cataractae) in the Red Deer River, Alberta, Canada.

The Red Deer River, Alberta, Canada is a prairie river that is impacted by the point-source input of Red Deer's municipal wastewater effluent and non-point- source agricultural runoff. We used population, growth, and physiological performance end points in longnose dace (Rhinichthys cataractae), an endemic and abundant minnow, to evaluate changes in fish health over a 220 km section of the Red Deer River. Longnose dace immediately downstream of Red Deer had elevated catch per unit effort with larger body and liver sizes compared to upstream of Red Deer sites, likely due to elevated riverine productivity from Red Deer's wastewater effluent. Longnose dace immediately downstream of Red Deer showed depressed testosterone production capacity and elevated ethoxyresorufin-O-deethylase (EROD) activity, which is consistent with exposure to endocrine-disrupting compounds and aromatic hydrocarbons, respectively. Longnose dace 150-180 km downstream of Red Deer had reduced liver and gonad sizes, elevated EROD, and increased 11-ketotestosterone production capacity compared to upstream of Red Deer sites, possibly related to a non-point-source agricultural influence on water quality. Longnose dace populations at the most downstream sites were missing the oldest age classes and might reach sexual maturity faster than at upstream sites, which is consistent with a younger age structure. Our results highlight the importance of assessing multiple performance end points to reveal physiological or reproductive effects in natural fish populations. We have demonstrated how longnose dace populations change over a river impacted by municipal wastewater and agricultural runoff; further studies are required to determine if these changes will influence the long-term viability of longnose dace in the Red Deer River.