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This longitudinal study explores evidence of learning and reflexivity among experts involved in the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Values Assessment from 2018 to 2022. As part of an online survey administered at yearly intervals, experts self-reported their views on: i) the aims they attributed to the Values Assessment , ii) their epistemic worldviews, iii) the definition of the multiple values of nature, and iv) their personal learning experiences in the assessment process. The represented epistemic worldviews corresponded to Constructivist, Transformative, Pragmatist, and Post-positivist. Across the three surveys, 59% of the respondents shifted their epistemic worldviews. However, these same experts did not change their core perspectives regarding the motivation behind the Values Assessment. At the same time, experts holding a Post-positivist worldview came to express more engagement-inclined themes and openness to dialogue with diverse knowledge systems. While enhanced reflexivity stimulated overall learning, cutting across all learning dimensions, it was itself a multilayered learning outcome. This study illustrates how diverse experts critically reflected and changed their own underlying assumptions during the inter- and transdisciplinary process of the Values Assessment. It further reveals that learning experiences in the Values Assessment were embedded in epistemic worldviews and connected to cognitive, relational, and transformative dimensions of learning. Our findings have broader implications for the design of inclusive and reflexive learning processes in future work of organisations aiming to facilitate inter- and transdisciplinary practices at the science-policy interface. • The IPBES process challenged experts to reflect active engagement with larger society. • Experts' epistemic worldviews and understandings shifted during a four-year IPBES process. • The degree and limits of reflection were ingrained partly in epistemic worldviews. • Epistemic worldviews connected to cognitive, relational, and transformative learning types. [ABSTRACT FROM AUTHOR]

• Reflexive analysis of IPBES experts' philosophical assumptions reveals how expertise is constituted in the Values Assessment. • Transformative and Constructive worldviews are less presented than Pragmatist and Post-positivists in the IPBES Values Assessment. • Consideration of plurality of epistemic worldviews is required in inter- and transdisciplinary teams. This study identifies and analyses the underlying assumptions of experts involved in the first author meeting (FAM) of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES)'s Values Assessment , and how they shape understandings of the multiple values of nature. We draw from survey data collected from 94 experts attending the FAM. Respondents self-report the tendencies and aims they bring to the assessment (i.e. motivation), the type and amount of evidence they require for knowledge to be valid (i.e. confirmation) and their epistemic worldviews (i.e. objectivity). Four clusters emerged that correspond to Pragmatist, Post-Positivist, Constructivist and Transformative epistemic worldviews. This result clarifies how different knowledge claims are represented in science-policy processes. Despite the proportionately higher number of social scientists in the Values Assessment , compared with previous IPBES assessments, we still found that fewer experts have Constructivist or Transformative worldviews than Pragmatist or Post-Positivist outlooks, an imbalance that may influence the types of values and valuation perspectives emphasised in the assessment. We also detected a tension regarding what constitutes valid knowledge between Post-Positivists, who emphasised high levels of agreement, and Pragmatists and Constructivists, who did not necessarily consider agreement crucial. Conversely, Post-Positivists did not align with relational values and were more diverse in their views regarding definitions of multiple values of nature compared to other clusters. Pragmatists emphasized relational values, while Constructivists tended to consider all value types (including relational values) as important. We discuss the implications of our findings for future design and delivery of IPBES processes and interdisciplinary research. [ABSTRACT FROM AUTHOR]

Achieving the intertwined goals of justice and sustainability requires transformative changes to meaningfully engage diverse perspectives. Therefore, scholars and policymakers need new ways of recognising and addressing nature's multiple values across cultures, disciplines and other knowledge traditions. By reviewing academic publications, policy documents and Indigenous and local community sources, we developed an inclusive typology of nature's values to clarify value concepts and guide their consideration in decisions. Through case studies, we illustrate how navigating 'horizontal' and 'vertical' interactions within and across this typology can help confront plural-value challenges, such as enhancing inclusive participation in environmental research and practice, and effective management of socio-environmental conflicts. We conclude by exploring how this typology of values can further leverage transformative change in other decision-making contexts. [ABSTRACT FROM AUTHOR]

Purpose We report the outcomes in patients with muscle invasive bladder cancer from 2 institutions who experienced a clinically complete response to neoadjuvant platinum based chemotherapy and elected active surveillance. It was unknown whether conservative treatment could be safely implemented in these patients. Materials and Methods We retrospectively reviewed the records of patients with muscle invasive bladder cancer at our institutions who elected surveillance following a clinically complete response to transurethral resection of bladder tumors and neoadjuvant chemotherapy from 2001 to 2017. A clinically complete response was defined as absent tumor on post-chemotherapy transurethral resection of bladder tumor, negative cytology and normal cross-sectional imaging. Results In the 148 patients followed a median of 55 months (range 5 to 145) the 5-year disease specific, overall, cystectomy-free and recurrence-free survival rates were 90%, 86%, 76% and 64%, respectively. Of the patients 71 (48%) experienced recurrence in the bladder, including 16 (11%) with muscle invasive disease and 55 (37%) with noninvasive disease. Salvage radical cystectomy prevented cancer specific death in 9 of 12 patients (75%) who underwent cystectomy after muscle invasive relapse and in 13 of 14 (93%) after noninvasive relapse. Conclusions We observed high rates of overall and disease specific survival with bladder preservation in patients who achieved a clinically complete response to neoadjuvant chemotherapy. These outcomes support the safety of active surveillance in carefully selected, closely monitored patients with muscle invasive bladder cancer. Future studies should aim to improve patient selection by identifying biomarkers predicting invasive relapse and developing novel imaging methods of early detection. [ABSTRACT FROM AUTHOR]

Purpose We evaluated the discordance between ureteroscopic biopsy and surgical pathology findings for grading and staging upper tract urothelial carcinoma. We also sought to establish preoperative predictors of aggressive tumors. Materials and Methods We retrospectively reviewed the records of 314 patients who underwent ureteroscopic biopsy followed by surgical management of upper tract urothelial carcinoma from 2000 to 2016 at a total of 3 institutions. Our primary outcomes were muscle invasive (pT2 or greater) disease at surgical pathology and upgrading of clinical low grade tumors to pathological high grade. Results At biopsy 61% of the patients had clinical high grade tumors and 21% had subepithelial connective tissue invasion (cT1+). On final pathology 79% of the patients had pathological high grade tumors and 45% had stage pT2 or greater. On multivariate analysis advanced patient age, clinical high grade and cT1+ were independently associated with pT2 or greater. The combined presence of clinical high grade and cT1+ had 86% positive predictive value for muscle invasion while the combined absence of clinical high grade and cT1+ had 80% negative predictive value. The likelihood of missing invasion on biopsy in patients with muscle invasive disease was increased when biopsy fragments were limited to 1 mm or less. Of clinical low grade cases on biopsy 51% were upgraded at surgery. The presence of positive urine cytology was associated with an increased risk of upgrading but this was not statistically significant. Conclusions Clinical high grade, cT1+ on biopsy and advanced patient age are independent risk factors for muscle invasive upper tract urothelial carcinoma. There is a significant risk of upgrading in patients with clinical low grade tumors on biopsy, especially when urine cytology is positive. The predictive value of biopsy can likely be improved by more extensive ureteroscopic sampling. [ABSTRACT FROM AUTHOR]

Purpose We investigated the impact of surgeon annual case volume on reoperation rates after inflatable penile prosthesis surgery. Materials and Methods The New York Statewide Planning and Research Cooperative System database was queried for inflatable penile prosthesis cases from 1995 to 2014. Multivariate proportional hazards regression was performed to estimate the impact of surgeon annual case volume on inflatable penile prosthesis reoperation rates. We stratified our analysis by indication for reoperation to determine if surgeon volume had a similar effect on infectious and noninfectious complications. Results A total of 14,969 men underwent inflatable penile prosthesis insertion. Median followup was 95.1 months (range 0.5 to 226.7) from the time of implant. The rates of overall reoperation, reoperation for infection and reoperation for noninfectious complications were 6.4%, 2.5% and 3.9%, respectively. Implants placed by lower volume implanters were more likely to require reoperation for infection but not for noninfectious complications. Multivariable analysis demonstrated that compared with patients treated by surgeons in the highest quartile of annual case volume (more than 31 cases per year), patients treated by surgeons in the lowest (0 to 2 cases per year), second (3 to 7 cases per year) and third (8 to 31 cases per year) annual case volume quartiles were 2.5 (p <0.001), 2.4 (p <0.001) and 2.1 (p=0.01) times more likely to require reoperation for inflatable penile prosthesis infection, respectively. Conclusions Patients treated by higher volume implanters are less likely to require reoperation after inflatable penile prosthesis insertion than those treated by lower volume surgeons. This trend appears to be driven by associations between surgeon volume and the risk of prosthesis infection. [ABSTRACT FROM AUTHOR]

• Riparian buffers are key places to reforest to increase ecosystem services. • Implementing existing riparian protection law in Costa Rica can lead to outsized benefits. • Small increase in forest cover leads to large increases in water quality via increased sediment and nutrient retention. • Increases in water quality are delivered to people who rely on surface water. • Reforesting benefits vulnerable populations in Costa Rica. Riparian buffers—forests along rivers—generate many essential ecosystem services, and their protection and restoration are the focus of many policy efforts. Costa Rica is a global leader in this regard, where legislative and executive frameworks work in concert to conserve forests that deliver public benefits such as water quality and carbon storage both locally and globally. Yet implementation and enforcement is an urgent challenge, and could benefit from high-resolution targeting with a quantitative understanding of expected benefits. Here, we undertake such an analysis, focusing on the benefits of implementing Forest Law 7575, which specifies the amount of forest to be preserved along rivers. We model changes in sediment retention, nutrient retention, and carbon sequestration from a baseline scenario based on current land use that is in partial compliance with the law. We contrast this with a simulated reforestation scenario, where riparian forest cover is increased to at least a minimum level of compliance (10 m buffers) everywhere. We find that targeted riparian reforestation—increasing national forest cover by 1.9 %—would substantially increase ecosystem services. Water quality regulation would be improved via an increase of 3.9 % in sediment retention (1.4 Mt/year), 81.4 % in nitrogen retention (0.012 Mt/year), and 85.9 % in phosphorus retention (0.0022 Mt/year). Moreover, riparian reforestation would increase the national carbon stock 1.4 % above current levels (7.0 Mt). Our analysis shows where riparian buffers are most beneficial—generally in steep, erosion-prone, and intensively fertilized landscapes. Through a canton-level analysis comparing potential increases in sediment and nutrient retention with demographic information, we find that these benefits would flow to communities that depend on rivers for drinking water and that are otherwise vulnerable. Small increases in riparian reforestation in Costa Rica, implemented via an existing law, could confer large benefits to rivers and all who depend on them. [ABSTRACT FROM AUTHOR]

Purpose Active surveillance is increasingly recommended for older men with low risk prostate cancer. Although older men have higher all cause mortality, they also have higher prostate cancer specific mortality. We hypothesized that older age is associated with an increased risk of Gleason score upgrading at confirmatory biopsy when controlling for prostate volume. Materials and Methods We retrospectively reviewed data on 1,130 patients with prostate cancer who were treated with active surveillance from 1991 through 2011. We included 646 patients with clinical Gleason 6 or less, stage T2a or less prostate cancer, a confirmatory biopsy within 2 years of diagnostic biopsy and prostate magnetic resonance imaging before confirmatory biopsy. The primary outcome was Gleason score upgrading to 7 or greater on confirmatory biopsy. We used logistic regression to estimate the effect of age on upgrading, adjusting for magnetic resonance imaging prostate volume and other potential confounders. Results Median age was 66 years (IQR 61–72) and median magnetic resonance imaging prostate volume was 41 ml (IQR 29–55). At confirmatory biopsy disease was upgraded in 55 of 646 patients (9%) and unchanged in 290 (45%) and biopsy was negative in 297 (46%). Older age was associated with higher odds of upgrading (adjusted OR 1.05, 95% CI 1.01–1.09, p = 0.009). Larger prostate volume was associated with lower odds of upgrading (adjusted OR 0.80/10 ml increase, 95% CI 0.7–0.9, p = 0.012). Conclusions Our findings suggest that older age is associated with an increased risk of misclassification on diagnostic biopsy. Older men who are interested in active surveillance should be counseled about the risks and benefits of confirmatory biopsy. [ABSTRACT FROM AUTHOR]

Targeting human-inhabited islands for invasive species eradication campaigns layers social complexity on top of technical complexity. Attaining widespread support and cooperation for eradications requires programs designed to meet diverse stakeholder needs. The Tierra del Fuego archipelago serves as an informative case study and model for understanding and incorporating private landowner preferences into a proposed eradication program. We employed a human-centered approach to characterize landowner perceptions, preferences, and potential support for a large-scale initiative to eradicate the invasive North American beaver ( Castor canadensis ) from Tierra del Fuego. We used a factorial vignette survey to understand how attributes of an eradication program are related landowners' decisions to participate. Landowners rated four programs that randomly varied by contract length, required level of landowner involvement, institutional administrator, payment, social norms, and probability of a successful eradication. Landowners in Tierra del Fuego were generally more willing to participate under three conditions: (1) increased payments, (2) increased expectations of program success, and (3) low requirements for landowner involvement. Our results suggest that incorporating feedbacks into program design can increase public support, and that landowners in Tierra del Fuego may not express the same preference for autonomy that exists in other regions of the world. Understanding and incorporating stakeholder preferences, perceptions, and beliefs into management strategies is an ongoing challenge for conservation practitioners worldwide. The vignette survey approach provides a cost-effective, rapid, and scalable tool to document and incorporate local values into conservation program design. Programs built using a human-centered approach will complement landowners’ land-use objectives, increase cooperation, and ultimately improve conservation outcomes. [ABSTRACT FROM AUTHOR]

Purpose We determined the extent to which complications as well as number of hospital-free days within 30 and 90 days of surgery predicted health related quality of life 1 year after radical cystectomy. Materials and Methods We used data from a prospective health related quality of life study using a validated instrument, the Vanderbilt Cystectomy Index-15. Complications were graded by the Clavien system, and hospital length of stay and length of stay during readmissions were used to calculate 30 and 90-day hospital-free days, respectively. We compared the number of hospital-free days among patients with varying levels of complications. Multivariate analysis was performed to determine predictors of Vanderbilt Cystectomy Index-15 score 1 year after surgery adjusting for demographic (age, gender, comorbidities) and clinical variables (stage and diversion type). Results A total of 100 patients with complete baseline and 1-year followup health related quality of life data were included in the analysis. Median (IQR) 30 and 90-day hospital-free days were 24 (22–25) and 84 (82–85), respectively. Patients who experienced any complications had significantly fewer 30-day hospital-free days (22 vs 24 days, p <0.01) and 90-day hospital-free days (81 vs 84 days, p <0.01), and patients with higher grade complications had fewer hospital-free days than those with lower grade or no complications (p <0.01). On multivariate analysis female gender and baseline Vanderbilt Cystectomy Index-15 score independently predicted higher 1-year health related quality of life scores. Conclusions Patients who experience complications after radical cystectomy have fewer 30 and 90-day hospital-free days. However, neither predicts health related quality of life at 1 year. Instead, long-term health related quality of life appears to be driven largely by baseline health related quality of life and gender. [ABSTRACT FROM AUTHOR]

Purpose: Radical prostatectomy is a common treatment for organ confined prostate cancer and its use is increasing. We examined how the increased volume is being distributed and what hospital characteristics are associated with increasing volume. Materials and Methods: We identified all men age 40 to less than 80 years who underwent radical prostatectomy for prostate cancer from 2000 to 2008 in the NIS (Nationwide Inpatient Sample) (586,429). Ownership of a surgical robot was determined using the 2007 AHA (American Hospital Association) Annual Survey. The association between hospital radical prostatectomy volume and hospital characteristics, including ownership of a robot, was explored using multivariate linear regression. Results: From 2000 to 2008 there was a 74% increase in the number of radical prostatectomies performed (p = 0.05) along with a 19% decrease in the number of hospitals performing radical prostatectomy (p <0.001), resulting in an increase in annual hospital radical prostatectomy volume (p = 0.009). Several hospital variables were associated with greater radical prostatectomy volume including teaching status, urban location, large bed size and ownership of a robot in 2007. On multivariate analysis the year, teaching status, large bed size, urban location and presence of a robot were associated with higher hospital radical prostatectomy volume. Conclusions: Use of radical prostatectomy increased significantly between 2000 and 2008, most notably after 2005. The increase in radical prostatectomy resulted in centralization to select hospitals, particularly those in the top radical prostatectomy volume quartile and those investing in robotic technology. Our findings support the hypothesis that hospitals with the greatest volume increases are specialty centers already performing a high volume of radical prostatectomy procedures. [Copyright &y& Elsevier]

Purpose: Robot-assisted laparoscopic radical cystectomy has been increasingly used to decrease the morbidity of radical cystectomy. However, whether it truly lowers the complication rate compared to open radical cystectomy is not well established. We examined the benign ureteroenteric anastomotic stricture rates of open and robot-assisted laparoscopic radical cystectomy. Materials and Methods: In the 478 consecutive patients who underwent radical cystectomy at our institution from December 2007 to December 2011 we examined the proportion diagnosed with benign ureteroenteric anastomotic stricture. Clinicopathological variables were compared by treatment group. Cox multivariable analysis was performed to determine which patient or disease specific factors were independently associated with stricture diagnosis. Results: A total of 375 patients (78.5%) underwent open radical cystectomy and 103 (21.5%) underwent robot-assisted laparoscopic radical cystectomy. Of the patients 45 (9.4%) were diagnosed with ureteroenteric anastomotic stricture a median of 5.3 months postoperatively. There was no difference in the stricture rate between the open and robot-assisted groups (8.5% vs 12.6%, p = 0.21). On adjusted Cox proportional hazards analysis no patient variable was independently associated with stricture diagnosis, including operative approach. Conclusions: Of the patients 9.4% were diagnosed with benign ureteroenteric anastomotic stricture after radical cystectomy with no significant difference in the risk of diagnosis by surgical approach. No patient or disease specific factor was independently associated with an increased risk of stricture diagnosis. Ureteroenteric anastomotic stricture is likely related to surgical technique. Continued efforts are needed to refine the technique of open and robot-assisted laparoscopic radical cystectomy to minimize the occurrence of this critical complication. [Copyright &y& Elsevier]

Purpose: Most long-term morbidity after radical cystectomy is related to the urinary diversion or reconstruction. While there are benefits to an orthotopic neobladder, there can be a substantial risk of voiding dysfunction in women. We examine the prevalence of postoperative voiding complications in women who underwent orthotopic neobladder diversion. Materials and Methods: We identified all women who underwent radical cystectomy and orthotopic neobladder for bladder cancer at our institution from 1996 to 2011 (51) and included patients with regular clinic followup (49). The presence and severity of incontinence and hypercontinence were evaluated at routine clinic visits. Unadjusted analyses were performed to measure the association between patient variables and voiding symptoms, with p <0.05 considered significant. Results: Daytime incontinence, nighttime incontinence and hypercontinence were reported by 43%, 55% and 31% of women, respectively. A neobladder-vaginal fistula developed in 3 women (6%). On unadjusted analysis having daytime incontinence was associated with a concurrent or previous hysterectomy (p = 0.031), but not with age, disease stage, preoperative incontinence, year of surgery or sparing the vaginal wall. The severity of daytime incontinence was associated with preoperative incontinence only (p = 0.02). The presence and severity of nighttime incontinence were associated with patient age only (p = 0.013, p = 0.005, respectively). Hypercontinence was not associated with any variable. Conclusions: Among women with orthotopic neobladder after radical cystectomy we identified a significant prevalence of voiding dysfunction. We recommend preoperative discussion of these possible complications with any woman interested in orthotopic neobladder to establish realistic expectations. For properly selected women who understand these risks, orthotopic neobladder may be an appropriate diversion choice. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Congenital ureteropelvic junction obstruction may present with flank pain, commonly referred to as a Dietl’s crisis. We report on a similar presentation of primary megaureter. Methods and Materials: We identified all patients with any diagnosis of megaureter treated at our institution between 1993 and 2009 (n = 465). We included 103 patients with primary megaureter and, of these, identified patients presenting with pain. All patients with secondary megaureter were excluded. Results: Seventeen patients (20 megaureters) presented with pain and 10 (13 megaureters) presented with an acute pain crisis. Median age at presentation was 77 months. Seven children initially presented to the emergency department for evaluation and two of them required urgent stent placement for intractable pain. Obstruction was diagnosed in 8 patients. Six patients underwent ureteral reimplantation. Four patients were initially observed: one failed observation at 12 months due to worsening hydronephrosis and required surgery, one was lost to follow up, and two are still successfully being followed. All patients who underwent surgery had pain resolution. Conclusion: In this contemporary cohort, approximately 17% of patients with primary megaureter presented with pain and 10% presented with an acute pain crisis. Most presenting in acute pain required surgery, which resolved presenting symptoms. [Copyright &y& Elsevier]

Purpose: Post-prostatectomy urinary incontinence can impact health related quality of life in men treated with radical prostatectomy for prostate cancer. Currently no consensus exists on which patients are at risk for impaired health related quality of life secondary to post-prostatectomy urinary incontinence. Using trajectory clustering analysis we identified predictors of post-prostatectomy urinary incontinence recovery in unique patient groups. Materials and Methods: In a 5-year period health related quality of life was evaluated in patients treated with radical prostatectomy using UCLA-PCI preoperatively, and 3, 6 and 12 months postoperatively. We used a novel cluster modeling technique to identify unique group trajectories of urinary function recovery with time. Results: Group based modeling of UCLA-PCI urinary function scores identified 3 distinct post-prostatectomy urinary incontinence recovery patterns. The 73 group 1 patients had a significant postoperative decrease with only 33.4% of optimum function at 12 months. The 258 group 2 patients had moderately decreased urinary function at 3 months with improvement to 76.8% of optimum function at 12 months. The 89 group 3 patients had high scores throughout. Group 1 patients tended to be older (p = 0.001), have major depression (p = 0.008) and lower extremity circulatory disease (p = 0.004), be a past or a current smoker (p = 0.004) and have more comorbidities (p <0.001) than those in groups 2 and 3. On multivariate analysis age and the number of comorbidities significantly predicted inclusion in the poor function group. Conclusions: A novel modeling approach identified 3 distinct post-prostatectomy urinary incontinence recovery patterns. Patient age and the number of comorbidities predicted worse outcome. These findings have implications for preoperative patient counseling and early intervention for post-prostatectomy urinary incontinence. [ABSTRACT FROM AUTHOR]

Abstract: The sub-Antarctic biome of South America is the world''s southernmost forested ecosystem and one of the last remaining wilderness areas on the planet. Nonetheless, the region confronts various anthropogenic environmental impacts, such as the invasive North American beaver (Castor canadensis) and timber harvesting, particularly in stands of Nothofagus pumilio. Both of these disturbances can affect terrestrial and aquatic systems. To understand the influence and relative importance of these disturbances on sub-Antarctic watersheds, we characterized in-stream and riparian habitat conditions (pH, dissolved oxygen, conductivity, temperature, stream size, distance to riparian forest, bank slope, substrate heterogeneity, benthic organic matter) and benthic macroinvertebrate community structure (density, richness, diversity, evenness) and function (biomass, functional feeding group percent) in 19 streams on Tierra del Fuego Island. To explain the effects of beaver invasion and timber harvesting, we compared these physical and biotic variables among four habitat types: (a) beaver meadows, (b) shelterwood cut harvested areas without forested riparian zones, (c) variable retention harvested areas with riparian buffers, and (d) unmanaged old-growth primary forests. Most habitat variables were similar at all sites, except for dissolved oxygen (significantly higher in streams from old-growth primary forests). Benthic communities in beaver meadows had significantly lower diversity, compared to streams of unmanaged old-growth primary forests, and managed sites presented intermediate values between the two. Functionally, the benthic community in beaver meadows displayed a reduction of all functional feeding groups except collector-gatherers; again variable retention harvested areas with riparian buffers were similar to unmanaged old-growth primary forest streams, while shelterwood cut harvested areas occupied an intermediate position. These results indicated that current forestry practices that include both variable retention and legally mandated riparian forested buffers may be effective in mitigating impacts on stream benthic communities. Finally, these data demonstrated that C. canadensis invasion was a relatively larger impact on these streams than well-managed forestry practices. [Copyright &y& Elsevier]

Andean Patagonia is experiencing sudden changes due to unorganized urban expansion. Despite being known for its wilderness areas, southern Patagonian urban streams have been increasingly studied during the last decade, using reference-impact gradients within urbanizing watersheds. Here, we assess urbanization effects on stream integrity by comparing environmental characteristics on independent reference streams vs. urban streams, and the benthic macroinvertebrate community structure along three stream reaches in an urbanization gradient. In comparison to reference sites, urban streams had higher nutrient concentrations, temperature, turbidity, stream flow, and total primary producer biomass, accompanied by lower dissolved oxygen concentrations, substrate particle size, mainly along mid and downstream areas. These variables were the main factors structuring macroinvertebrate assemblage ordination analysis. Macroinvertebrate assemblages from areas upstream from the urbanization differed from their counterparts in reference streams, but not from downstream reference areas. Environmental characteristics and biotic assemblage structure were altered in urban streams, even in reaches located upstream from urbanization, compared to independent upstream reference reaches. This study highlights the importance of a community and comparative vision towards independent areas with low impact to serve as reference values and establish appropriate goals or baselines when assessing ecological conditions and potential restoration. [ABSTRACT FROM AUTHOR]

Invasive species threaten global biodiversity, but multiple invasions make predicting the impacts difficult because of potential synergistic effects. We examined the impact of introduced beaver , brook trout , and rainbow trout on native stream fishes in the Cape Horn Biosphere Reserve, Chile. The combined effects of introduced species on the structure of the native freshwater fish community were quantified by electrofishing 28 stream reaches within four riparian habitat types (forest, grassland, shrubland, and beaver-affected habitat) in 23 watersheds and by measuring related habitat variables (water velocity, substrate type, depth, and the percentage of pools). Three native stream fish species (puye [also known as inanga], , and ) were found along with brook trout and rainbow trout, but puye was the only native species that was common and widespread. The reaches affected by beaver impoundments had significantly higher puye densities than all other reaches in this study. These results are comparable to those reported for other streams in southern Chile. The presence of trout reduced the abundance of puye, but only in beaver-affected areas; all three natural riparian habitat types had uniformly low puye abundance and were unaffected by the presence or absence of trout. The data suggest that one invasive species, the beaver, enhanced puye habitat and thereby increased the abundance of that species, which, in turn, helped moderate the negative impacts of invasive trout. [ABSTRACT FROM AUTHOR]