110 research outputs found

    Interactions among nutrients govern the global grassland biomass-precipitation relationship

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    Abstract Ecosystems are experiencing changing global patterns of mean annual precipitation (MAP) and enrichment with multiple nutrients that potentially colimit plant biomass production. In grasslands, mean aboveground plant biomass is closely related to MAP, but how this relationship changes after enrichment with multiple nutrients remains unclear. We hypothesized the global biomass–MAP relationship becomes steeper with an increasing number of added nutrients, with increases in steepness corresponding to the form of interaction among added nutrients and with increased mediation by changes in plant community diversity. We measured aboveground plant biomass production and species diversity in 71 grasslands on six continents representing the global span of grassland MAP, diversity, management, and soils. We fertilized all sites with nitrogen, phosphorus, and potassium with micronutrients in all combinations to identify which nutrients limited biomass at each site. As hypothesized, fertilizing with one, two, or three nutrients progressively steepened the global biomass–MAP relationship. The magnitude of the increase in steepness corresponded to whether sites were not limited by nitrogen or phosphorus, were limited by either one, or were colimited by both in additive, or synergistic forms. Unexpectedly, we found only weak evidence for mediation of biomass–MAP relationships by plant community diversity because relationships of species richness, evenness, and beta diversity to MAP and to biomass were weak or opposing. Site-level properties including baseline biomass production, soils, and management explained little variation in biomass–MAP relationships. These findings reveal multiple nutrient colimitation as a defining feature of the global grassland biomass–MAP relationship.Abstract Ecosystems are experiencing changing global patterns of mean annual precipitation (MAP) and enrichment with multiple nutrients that potentially colimit plant biomass production. In grasslands, mean aboveground plant biomass is closely related to MAP, but how this relationship changes after enrichment with multiple nutrients remains unclear. We hypothesized the global biomass–MAP relationship becomes steeper with an increasing number of added nutrients, with increases in steepness corresponding to the form of interaction among added nutrients and with increased mediation by changes in plant community diversity. We measured aboveground plant biomass production and species diversity in 71 grasslands on six continents representing the global span of grassland MAP, diversity, management, and soils. We fertilized all sites with nitrogen, phosphorus, and potassium with micronutrients in all combinations to identify which nutrients limited biomass at each site. As hypothesized, fertilizing with one, two, or three nutrients progressively steepened the global biomass–MAP relationship. The magnitude of the increase in steepness corresponded to whether sites were not limited by nitrogen or phosphorus, were limited by either one, or were colimited by both in additive, or synergistic forms. Unexpectedly, we found only weak evidence for mediation of biomass–MAP relationships by plant community diversity because relationships of species richness, evenness, and beta diversity to MAP and to biomass were weak or opposing. Site-level properties including baseline biomass production, soils, and management explained little variation in biomass–MAP relationships. These findings reveal multiple nutrient colimitation as a defining feature of the global grassland biomass–MAP relationship

    Interactions among nutrients govern the global grassland biomass-precipitation relationship

    Get PDF
    Ecosystems are experiencing changing global patterns of mean annual precipitation (MAP) and enrichment with multiple nutrients that potentially colimit plant biomass production. In grasslands, mean aboveground plant biomass is closely related to MAP, but how this relationship changes after enrichment with multiple nutrients remains unclear. We hypothesized the global biomass–MAP relationship becomes steeper with an increasing number of added nutrients, with increases in steepness corresponding to the form of interaction among added nutrients and with increased mediation by changes in plant community diversity. We measured aboveground plant biomass production and species diversity in 71 grasslands on six continents representing the global span of grassland MAP, diversity, management, and soils. We fertilized all sites with nitrogen, phosphorus, and potassium with micronutrients in all combinations to identify which nutrients limited biomass at each site. As hypothesized, fertilizing with one, two, or three nutrients progressively steepened the global biomass–MAP relationship. The magnitude of the increase in steepness corresponded to whether sites were not limited by nitrogen or phosphorus, were limited by either one, or were colimited by both in additive, or synergistic forms. Unexpectedly, we found only weak evidence for mediation of biomass–MAP relationships by plant community diversity because relationships of species richness, evenness, and beta diversity to MAP and to biomass were weak or opposing. Site-level properties including baseline biomass production, soils, and management explained little variation in biomass–MAP relationships. These findings reveal multiple nutrient colimitation as a defining feature of the global grassland biomass–MAP relationship

    Development and Assessment of a Patient-Reported Outcome Instrument for Gender-Affirming Care

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    Importance: There is an urgent need for a validated gender-affirming care-specific patient-reported outcome measure (PROM). Objective: To field test the GENDER-Q, a new PROM for gender-affirming care, in a large, international sample of transgender and gender diverse (TGD) adults and evaluate its psychometric properties. Design, Setting, and Participants: This international cross-sectional study was conducted among TGD adults aged 18 years and older who were seeking or had received gender-affirming care within the past 5 years at 21 clinical sites across Canada, the United States, the Netherlands, and Spain; participants were also recruited through community groups (eg, crowdsourcing platform, social media). The study was conducted between February 2022 and March 2024. Participants had to be capable of completing the instrument in English, Danish, Dutch, or French-Canadian. Eligible participants accessed an online REDCap survey to complete sociodemographic questions and questions about gender-affirming care they had received or sought (ie, to look, function, or feel masculine, feminine, gender fluid, or another way). Main Outcome and Measures: Branching logic was used to assign relevant instrument scales. Rasch measurement theory (RMT) analysis was used to examine the fit of the observed data to the Rasch model for each scale. Test-retest reliability and hypothesis-based construct validity of instrument scales were examined. The hypothesis was that instrument scale scores would increase with better outcomes on corresponding categorical questions. Results: A total of 5497 participants (mean [SD] age, 32.8 [12.3] years; 1837 [33.4%] men; 1307 [23.8%] nonbinary individuals; and 2036 [37.0%] women) completed the field test survey. Participants sought or had the following types of gender-affirming care: 2674 (48.6%) masculinizing, 2271 (41.3%) femininizing, and 552 (10.0%) other. RMT analysis led to the development of 54 unidimensional scales and 2 checklists covering domains of health-related quality of life, sexual, urination, gender practices, voice, hair, face and neck, body, breasts, genital feminization, chest, genital masculinization, and experience of care. Test-retest reliability of the scales (intraclass correlation coefficient [average] &gt;0.70) was demonstrated. Only 1 item (phalloplasty donor flap) had an ICC less than 0.70. As hypothesized, scores increased incrementally with better associated self-reported categorical responses. For example, among 661 participants who reported poor psychological well-being, the mean (SD) scale score was 45 (18) points; for those who reported excellent psychological well-being, the mean (SD) scale score was 85 (16) points (P &lt;.001). Conclusions and Relevance: In this cross-sectional study of 5497 TGD adults, the instrument demonstrated reliability and validity. The instrument was validated in an international sample and is designed to collect and compare evidence-based outcome data for gender-affirming care from the patients' perspective.</p

    Widening global variability in grassland biomass since the 1980s

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    Abstract Global change is associated with variable shifts in the annual production of aboveground plant biomass, suggesting localized sensitivities with unclear causal origins. Combining remotely sensed normalized difference vegetation index data since the 1980s with contemporary field data from 84 grasslands on 6 continents, we show a widening divergence in site-level biomass ranging from +51% to −34% globally. Biomass generally increased in warmer, wetter and species-rich sites with longer growing seasons and declined in species-poor arid areas. Phenological changes were widespread, revealing substantive transitions in grassland seasonal cycling. Grazing, nitrogen deposition and plant invasion were prevalent in some regions but did not predict overall trends. Grasslands are undergoing sizable changes in production, with implications for food security, biodiversity and carbon storage especially in arid regions where declines are accelerating.Abstract Global change is associated with variable shifts in the annual production of aboveground plant biomass, suggesting localized sensitivities with unclear causal origins. Combining remotely sensed normalized difference vegetation index data since the 1980s with contemporary field data from 84 grasslands on 6 continents, we show a widening divergence in site-level biomass ranging from +51% to −34% globally. Biomass generally increased in warmer, wetter and species-rich sites with longer growing seasons and declined in species-poor arid areas. Phenological changes were widespread, revealing substantive transitions in grassland seasonal cycling. Grazing, nitrogen deposition and plant invasion were prevalent in some regions but did not predict overall trends. Grasslands are undergoing sizable changes in production, with implications for food security, biodiversity and carbon storage especially in arid regions where declines are accelerating

    Healing through culturally embedded practice: an investigation of counsellors’ and clients’ experiences of Buddhist Counselling in Thailand

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    This thesis is concerned with an exploration of counsellors’ and clients’ lived experiences of Buddhist Counselling, an indigenous Buddhist-based counselling approach in Thailand. Over the past decade, Buddhist Counselling has received a growing interest from Thai counselling trainees and practitioners, and it has also expanded to serve Thai people in various settings. Research on Buddhist Counselling is very limited and most of the existing studies in the field have focused on measuring the effectiveness of the approach. While these studies have consistently indicated the positive effects of Buddhist Counselling on psychological improvement across several population groups, the significant questions of how Buddhist Counselling brings about such outcome and how it is experienced are still largely unanswered. Moreover, existing research is concentrated much more on clients’ views than counsellors’ views, although counsellors’ views of their counselling practice can also serve as a knowledge base of the field. This thesis thus sets out to contribute to rectifying this omission by exploring Buddhist Counselling from the perspectives of both counsellors and clients. The thesis is based on two qualitative studies. The first study addressed Buddhist Counselling from the perspective of five counsellors through a focus group and semi-structured interviews. The second study explored Buddhist Counselling from the perspective of three clients, using two semi-structured interviews with each of them. All data received were analysed using interpretative phenomenological analysis (IPA). The study reveals counsellors’ and clients’ overall positive experience of engaging in Buddhist Counselling. Central to the accounts of the counsellors are the following perceptions: that their practice of Buddhist Counselling is culturally congruent with the existing values and beliefs of both themselves and their clients; that their personal and professional congruence is key to their therapeutic efficacy; and that they enhance such congruence through their application of Buddhist ideas and practices in their daily lives. Key to the clients’ accounts is their emphasis on the significant roles of the counsellors’ Buddhist ideas and personal qualities, and of their religious practices in facilitating healing and change. Key shared findings from both studies reveal that the participants’ accounts of their cultural background and their experiences of Buddhist Counselling are intertwined. Adopting hermeneutics to address this intertwinement, I reveal the cultural and moral dimensions underlying the practice of Buddhist Counselling. Based on such revelation, I suggest that Buddhist Counselling in particular, as well as psychotherapy in general, should be better understood as a historically situated, culturally bound, and morally constituted activity of people who are concerned with improving the quality of their lives and their community, rather than the transcultural and merely relational work of morally-neutral practitioners

    Interactions among nutrients govern the global grassland biomass–precipitation relationship

    Get PDF
    Ecosystems are experiencing changing global patterns of mean annual precipitation (MAP) and enrichment with multiple nutrients that potentially colimit plant biomass production. In grasslands, mean aboveground plant biomass is closely related to MAP, but how this relationship changes after enrichment with multiple nutrients remains unclear. We hypothesized the global biomass–MAP relationship becomes steeper with an increasing number of added nutrients, with increases in steepness corresponding to the form of interaction among added nutrients and with increased mediation by changes in plant community diversity. We measured aboveground plant biomass production and species diversity in 71 grasslands on six continents representing the global span of grassland MAP, diversity, management, and soils. We fertilized all sites with nitrogen, phosphorus, and potassium with micronutrients in all combinations to identify which nutrients limited biomass at each site. As hypothesized, fertilizing with one, two, or three nutrients progressively steepened the global biomass–MAP relationship. The magnitude of the increase in steepness corresponded to whether sites were not limited by nitrogen or phosphorus, were limited by either one, or were colimited by both in additive, or synergistic forms. Unexpectedly, we found only weak evidence for mediation of biomass–MAP relationships by plant community diversity because relationships of species richness, evenness, and beta diversity to MAP and to biomass were weak or opposing. Site-level properties including baseline biomass production, soils, and management explained little variation in biomass–MAP relationships. These findings reveal multiple nutrient colimitation as a defining feature of the global grassland biomass–MAP relationship

    Widening global variability in grassland biomass since the 1980s

    Get PDF
    Global change is associated with variable shifts in the annual production of aboveground plant biomass, suggesting localized sensitivities with unclear causal origins. Combining remotely sensed normalized difference vegetation index data since the 1980s with contemporary field data from 84 grasslands on 6 continents, we show a widening divergence in site-level biomass ranging from +51% to −34% globally. Biomass generally increased in warmer, wetter and species-rich sites with longer growing seasons and declined in species-poor arid areas. Phenological changes were widespread, revealing substantive transitions in grassland seasonal cycling. Grazing, nitrogen deposition and plant invasion were prevalent in some regions but did not predict overall trends. Grasslands are undergoing sizable changes in production, with implications for food security, biodiversity and carbon storage especially in arid regions where declines are accelerating
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