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1.
Proc Natl Acad Sci U S A ; 119(15): e2119959119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377782

RESUMO

Biodiversity-mediated ecosystem services (ES) support human well-being, but their values are typically estimated individually. Although ES are part of complex socioecological systems, we know surprisingly little about how multiple ES interact ecologically and economically. Interactions could be positive (synergy), negative (trade-offs), or absent (additive effects), with strong implications for management and valuation. Here, we evaluate the interactions of two ES, pollination and pest control, via a factorial field experiment in 30 Costa Rican coffee farms. We found synergistic interactions between these two critical ES to crop production. The combined positive effects of birds and bees on fruit set, fruit weight, and fruit weight uniformity were greater than their individual effects. This represents experimental evidence at realistic farm scales of positive interactions among ES in agricultural systems. These synergies suggest that assessments of individual ES may underestimate the benefits biodiversity provides to agriculture and human well-being. Using our experimental results, we demonstrate that bird pest control and bee pollination services translate directly into monetary benefits to coffee farmers. Excluding both birds and bees resulted in an average yield reduction of 24.7% (equivalent to losing US$1,066.00/ha). These findings highlight that habitat enhancements to support native biodiversity can have multiple benefits for coffee, a valuable crop that supports rural livelihoods worldwide. Accounting for potential interactions among ES is essential to quantifying their combined ecological and economic value.


Assuntos
Café , Produção Agrícola , Controle de Pragas , Polinização , Biodiversidade
2.
Ecol Appl ; 31(3): e02260, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33185959

RESUMO

Spatial aspects of connectivity have received considerable attention from ecologists and conservationists, yet temporal connectivity, the periodic linking of habitats, plays an equally important, but largely overlooked role. Different biological and biophysical attributes of ecosystems underpin temporal connectivity, but here we focus on resource continuity, the uninterrupted availability of foraging sites. We test the response of pollinators to resource continuity at community, population, and individual levels using a novel natural experiment consisting of farms with either single or sequential cropping systems. We found significant effects at the population level; colony density of an important crop pollinator (Bombus impatiens L.) was greater when crop floral resources were continuously available. However, we did not find significant effects at the community or individual level; wild bee abundance, diversity and body size did not respond to resource continuity. Raspberry farms with greater early season resources provided by blueberry had greater bumble bee populations, suggesting beneficial effects on resource availability due to crop diversity. Better understanding the impact of resource continuity via crop diversity on broader patterns of biodiversity is essential for the co-management of biodiversity and ecosystem services.


Assuntos
Mirtilos Azuis (Planta) , Polinização , Animais , Abelhas , Biodiversidade , Ecossistema , Estações do Ano
3.
J Environ Manage ; 293: 112838, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34087647

RESUMO

Excess phosphorus loading to waterbodies has led to increasing frequency and severity of harmful algal blooms, negatively impacting economic activity and human health. While interventions to improve water quality can create large societal benefits, these investments are costly and the value of benefits is often unknown. Understanding the social and economic impacts of reduced phosphorus loading is critical for developing effective land use policies and for generating public and political support for these initiatives. Here, we quantify the social benefits and costs of improving water quality in Lake Champlain under a range of phosphorus reduction and climate change scenarios between 2016 and 2050. We use statistical models to link water quality outputs from an established integrated assessment model with three categories of benefits: tourism expenditures, property sales, and avoided human health impacts. We estimate the costs of reducing phosphorus loading using data reported by the State of Vermont. We find that under the most aggressive phosphorus reduction scenario, the total benefits of improved water quality are $55 to $60 million between 2016 and 2050. Over this 35 year time horizon, the combined benefits do not outweigh the costs under any scenario. If the time horizon is extended to 2100 or beyond, however, the benefits may exceed the costs if the applied discount rate is less than 3%. Importantly, we almost certainly underestimate the value of clean water, due to the omission of other types of benefits. Despite this uncertainty, our study provides a tractable framework for disentangling the complex relationships between water quality and human well-being, and illuminates the value of reductions in phosphorus loading to society.


Assuntos
Mudança Climática , Fósforo , Análise Custo-Benefício , Humanos , Lagos , Fósforo/análise , Qualidade da Água
4.
Ecol Lett ; 23(2): 326-335, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31797535

RESUMO

Supporting ecosystem services and conserving biodiversity may be compatible goals, but there is concern that service-focused interventions mostly benefit a few common species. We use a spatially replicated, multiyear experiment in four agricultural settings to test if enhancing habitat adjacent to crops increases wild bee diversity and abundance on and off crops. We found that enhanced field edges harbored more taxonomically and functionally abundant, diverse, and compositionally different bee communities compared to control edges. Enhancements did not increase the abundance or diversity of bees visiting crops, indicating that the supply of pollination services was unchanged following enhancement. We find that actions to promote crop pollination improve multiple dimensions of biodiversity, underscoring their conservation value, but these benefits may not be spilling over to crops. More work is needed to identify the conditions that promote effective co-management of biodiversity and ecosystem services.


Assuntos
Biodiversidade , Ecossistema , Agricultura , Animais , Abelhas , Produtos Agrícolas , Polinização
5.
Proc Natl Acad Sci U S A ; 114(39): 10438-10442, 2017 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-28893985

RESUMO

Climate change will cause geographic range shifts for pollinators and major crops, with global implications for food security and rural livelihoods. However, little is known about the potential for coupled impacts of climate change on pollinators and crops. Coffee production exemplifies this issue, because large losses in areas suitable for coffee production have been projected due to climate change and because coffee production is dependent on bee pollination. We modeled the potential distributions of coffee and coffee pollinators under current and future climates in Latin America to understand whether future coffee-suitable areas will also be suitable for pollinators. Our results suggest that coffee-suitable areas will be reduced 73-88% by 2050 across warming scenarios, a decline 46-76% greater than estimated by global assessments. Mean bee richness will decline 8-18% within future coffee-suitable areas, but all are predicted to contain at least 5 bee species, and 46-59% of future coffee-suitable areas will contain 10 or more species. In our models, coffee suitability and bee richness each increase (i.e., positive coupling) in 10-22% of future coffee-suitable areas. Diminished coffee suitability and bee richness (i.e., negative coupling), however, occur in 34-51% of other areas. Finally, in 31-33% of the future coffee distribution areas, bee richness decreases and coffee suitability increases. Assessing coupled effects of climate change on crop suitability and pollination can help target appropriate management practices, including forest conservation, shade adjustment, crop rotation, or status quo, in different regions.


Assuntos
Abelhas/classificação , Mudança Climática , Coffea/crescimento & desenvolvimento , Café/economia , Produtos Agrícolas/economia , Produtos Agrícolas/crescimento & desenvolvimento , Polinização/fisiologia , Agricultura/economia , Animais , Abelhas/fisiologia , Ecossistema , Fazendas/economia
6.
Am J Bot ; 106(11): 1412-1422, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31675110

RESUMO

PREMISE: Most plants interact with mycorrhizal fungi and animal pollinators simultaneously. Yet, whether mycorrhizae affect traits important to pollination remains poorly understood and may depend on the match between host and fungal genotypes. Here, we examined how ericoid mycorrhizal fungi affected flowering phenology, floral traits, and reproductive success, among eight genotypes of highbush blueberry, Vaccinium corymbosum (Ericaceae). We asked three overarching questions: (1) Do genotypes differ in response to inoculation? (2) How does inoculation affect floral and flowering traits? (3) Are inoculated plants more attractive to pollinators and less pollen limited than non-inoculated plants of the same genotype? METHODS: To examine these questions, we experimentally inoculated plants with ericoid mycorrhizal fungi, grew the plants in the field, and measured flowering and floral traits over 2 years. In year 2, we conducted a hand-pollination experiment to test whether plants differed in pollen limitation. RESULTS: Inoculated plants had significantly higher levels of colonization for some genotypes, and there were significant floral trait changes in inoculated plants for some genotypes as well. On average, inoculated plants produced significantly larger floral displays, more fruits per inflorescence, and heavier fruits with lower sugar content, than non-inoculated, control plants. Hand pollination enhanced the production of fruits, and fruit mass, for non-inoculated plants but not for those that were inoculated. CONCLUSIONS: Our results demonstrate that inoculation with ericoid mycorrhizal fungi enhanced flowering and altered investment in reproduction in genotype-specific ways. These findings underscore the importance of examining belowground symbionts and genotype-specific responses in their hosts to fully understand the drivers of aboveground interactions.


Assuntos
Mirtilos Azuis (Planta) , Ericaceae , Micorrizas , Animais , Flores , Genótipo , Polinização , Reprodução
7.
Conserv Biol ; 33(4): 942-952, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30614054

RESUMO

Safeguarding ecosystem services and biodiversity is critical to achieving sustainable development. To date, ecosystem services quantification has focused on the biophysical supply of services with less emphasis on human beneficiaries (i.e., demand). Only when both occur do ecosystems benefit people, but demand may shift ecosystem service priorities toward human-dominated landscapes that support less biodiversity. We quantified how accounting for demand affects the efficiency of conservation in capturing both human benefits and biodiversity by comparing conservation priorities identified with and without accounting for demand. We mapped supply and benefit for 3 ecosystem services (flood mitigation, crop pollination, and nature-based recreation) by adapting existing ecosystem service models to include and exclude factors representing human demand. We then identified conservation priorities for each with the conservation planning program Marxan. Particularly for flood mitigation and crop pollination, supply served as a poor proxy for benefit because demand changed the spatial distribution of ecosystem service provision. Including demand when jointly targeting biodiversity and ecosystem service increased the efficiency of conservation efforts targeting ecosystem services without reducing biodiversity outcomes. Our results highlight the importance of incorporating demand when quantifying ecosystem services for conservation planning.


Efectos de la Demanda Humana sobre la Planeación de la Conservación para la Biodiversidad y los Servicios Ambientales Resumen La salvaguardia de los servicios ambientales y de la biodiversidad es muy importante para lograr el desarrollo sustentable. A la fecha, la cuantificación de los servicios ambientales se ha enfocado en el suministro biofísico de servicios con un menor énfasis en los beneficiarios humanos (es decir, la demanda). Es sólo cuando se considera a ambos que los ecosistemas benefician a las personas, pero la demanda puede cambiar las prioridades de los servicios ambientales hacia los paisajes dominados por humanos, los cuales mantienen una menor biodiversidad. Cuantificamos cómo afecta la consideración de la demanda a la eficiencia de la conservación en la captura de los beneficios humanos y de la biodiversidad al comparar las prioridades de conservación con y sin la consideración de la demanda. Mapeamos el suministro y el beneficio para tres servicios ambientales (mitigación de inundaciones, polinización de cultivos y actividades recreativas basadas en la naturaleza) al adaptar los modelos de servicios ambientales existentes para que incluyeran y excluyeran los factores que representan la demanda humana. Después identificamos las prioridades de conservación para cada uno con el programa de planeación de la conservación Marxan. En el caso particular de la mitigación de inundaciones y la polinización de cultivos, el suministro fue un sustituto pobre para el beneficio debido a que la demanda cambió la distribución espacial de la provisión de servicios ambientales. La inclusión de la demanda cuando nos enfocamos en la biodiversidad y en los servicios ambientales como conjunto incrementó la eficiencia de los esfuerzos de conservación enfocados en los servicios ambientales sin reducir los resultados para la biodiversidad. Nuestros resultados resaltan la importancia de la incorporación de la demanda cuando se cuantifican los servicios ambientales para la planeación de la conservación.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Inundações , Humanos , Polinização
8.
Proc Natl Acad Sci U S A ; 113(7): 1760-5, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26831101

RESUMO

Research about ecosystem services (ES) often aims to generate knowledge that influences policies and institutions for conservation and human development. However, we have limited understanding of how decision-makers use ES knowledge or what factors facilitate use. Here we address this gap and report on, to our knowledge, the first quantitative analysis of the factors and conditions that explain the policy impact of ES knowledge. We analyze a global sample of cases where similar ES knowledge was generated and applied to decision-making. We first test whether attributes of ES knowledge themselves predict different measures of impact on decisions. We find that legitimacy of knowledge is more often associated with impact than either the credibility or salience of the knowledge. We also examine whether predictor variables related to the science-to-policy process and the contextual conditions of a case are significant in predicting impact. Our findings indicate that, although many factors are important, attributes of the knowledge and aspects of the science-to-policy process that enhance legitimacy best explain the impact of ES science on decision-making. Our results are consistent with both theory and previous qualitative assessments in suggesting that the attributes and perceptions of scientific knowledge and process within which knowledge is coproduced are important determinants of whether that knowledge leads to action.


Assuntos
Conservação dos Recursos Naturais , Ecossistema
9.
Proc Natl Acad Sci U S A ; 113(1): 140-5, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26699460

RESUMO

Wild bees are highly valuable pollinators. Along with managed honey bees, they provide a critical ecosystem service by ensuring stable pollination to agriculture and wild plant communities. Increasing concern about the welfare of both wild and managed pollinators, however, has prompted recent calls for national evaluation and action. Here, for the first time to our knowledge, we assess the status and trends of wild bees and their potential impacts on pollination services across the coterminous United States. We use a spatial habitat model, national land-cover data, and carefully quantified expert knowledge to estimate wild bee abundance and associated uncertainty. Between 2008 and 2013, modeled bee abundance declined across 23% of US land area. This decline was generally associated with conversion of natural habitats to row crops. We identify 139 counties where low bee abundances correspond to large areas of pollinator-dependent crops. These areas of mismatch between supply (wild bee abundance) and demand (cultivated area) for pollination comprise 39% of the pollinator-dependent crop area in the United States. Further, we find that the crops most highly dependent on pollinators tend to experience more severe mismatches between declining supply and increasing demand. These trends, should they continue, may increase costs for US farmers and may even destabilize crop production over time. National assessments such as this can help focus both scientific and political efforts to understand and sustain wild bees. As new information becomes available, repeated assessments can update findings, revise priorities, and track progress toward sustainable management of our nation's pollinators.


Assuntos
Abelhas/fisiologia , Produtos Agrícolas , Polinização , Animais , Fazendeiros , Humanos , Modelos Biológicos , Dinâmica Populacional , Estados Unidos
10.
Proc Natl Acad Sci U S A ; 112(24): 7348-55, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26082539

RESUMO

The central challenge of the 21st century is to develop economic, social, and governance systems capable of ending poverty and achieving sustainable levels of population and consumption while securing the life-support systems underpinning current and future human well-being. Essential to meeting this challenge is the incorporation of natural capital and the ecosystem services it provides into decision-making. We explore progress and crucial gaps at this frontier, reflecting upon the 10 y since the Millennium Ecosystem Assessment. We focus on three key dimensions of progress and ongoing challenges: raising awareness of the interdependence of ecosystems and human well-being, advancing the fundamental interdisciplinary science of ecosystem services, and implementing this science in decisions to restore natural capital and use it sustainably. Awareness of human dependence on nature is at an all-time high, the science of ecosystem services is rapidly advancing, and talk of natural capital is now common from governments to corporate boardrooms. However, successful implementation is still in early stages. We explore why ecosystem service information has yet to fundamentally change decision-making and suggest a path forward that emphasizes: (i) developing solid evidence linking decisions to impacts on natural capital and ecosystem services, and then to human well-being; (ii) working closely with leaders in government, business, and civil society to develop the knowledge, tools, and practices necessary to integrate natural capital and ecosystem services into everyday decision-making; and (iii) reforming institutions to change policy and practices to better align private short-term goals with societal long-term goals.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Tomada de Decisões , Ecologia/economia , Ecologia/métodos , Ecologia/tendências , Humanos , Política Pública
11.
Proc Natl Acad Sci U S A ; 110(47): 18753-60, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24218556

RESUMO

Human activity is rapidly transforming most of Earth's natural systems. How this transformation is impacting human health, whose health is at greatest risk, and the magnitude of the associated disease burden are relatively new subjects within the field of environmental health. We discuss what is known about the human health implications of changes in the structure and function of natural systems and propose that these changes are affecting human health in a variety of important ways. We identify several gaps and limitations in the research that has been done to date and propose a more systematic and comprehensive approach to applied research in this field. Such efforts could lead to a more robust understanding of the human health impacts of accelerating environmental change and inform decision making in the land-use planning, environmental conservation, and public health policy realms.


Assuntos
Ecossistema , Saúde Ambiental/tendências , Nível de Saúde , Atividades Humanas , Pesquisa , Saúde Ambiental/métodos , Humanos
12.
Geohealth ; 8(3): e2022GH000764, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38425366

RESUMO

Ecosystem change can profoundly affect human well-being and health, including through changes in exposure to vector-borne diseases. Deforestation has increased human exposure to mosquito vectors and malaria risk in Africa, but there is little understanding of how socioeconomic and ecological factors influence the relationship between deforestation and malaria risk. We examined these interrelationships in six sub-Saharan African countries using demographic and health survey data linked to remotely sensed environmental variables for 11,746 children under 5 years old. We found that the relationship between deforestation and malaria prevalence varies by wealth levels. Deforestation is associated with increased malaria prevalence in the poorest households, but there was not significantly increased malaria prevalence in the richest households, suggesting that deforestation has disproportionate negative health impacts on the poor. In poorer households, malaria prevalence was 27%-33% larger for one standard deviation increase in deforestation across urban and rural populations. Deforestation is also associated with increased malaria prevalence in regions where Anopheles gambiae and Anopheles funestus are dominant vectors, but not in areas of Anopheles arabiensis. These findings indicate that deforestation is an important driver of malaria risk among the world's most vulnerable children, and its impact depends critically on often-overlooked social and biological factors. An in-depth understanding of the links between ecosystems and human health is crucial in designing conservation policies that benefit people and the environment.

13.
PLOS Digit Health ; 3(4): e0000473, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38602898

RESUMO

Consumer wearables have been successful at measuring sleep and may be useful in predicting changes in mental health measures such as stress. A key challenge remains in quantifying the relationship between sleep measures associated with physiologic stress and a user's experience of stress. Students from a public university enrolled in the Lived Experiences Measured Using Rings Study (LEMURS) provided continuous biometric data and answered weekly surveys during their first semester of college between October-December 2022. We analyzed weekly associations between estimated sleep measures and perceived stress for participants (N = 525). Through mixed-effects regression models, we identified consistent associations between perceived stress scores and average nightly total sleep time (TST), resting heart rate (RHR), heart rate variability (HRV), and respiratory rate (ARR). These effects persisted after controlling for gender and week of the semester. Specifically, for every additional hour of TST, the odds of experiencing moderate-to-high stress decreased by 0.617 or by 38.3% (p<0.01). For each 1 beat per minute increase in RHR, the odds of experiencing moderate-to-high stress increased by 1.036 or by 3.6% (p<0.01). For each 1 millisecond increase in HRV, the odds of experiencing moderate-to-high stress decreased by 0.988 or by 1.2% (p<0.05). For each additional breath per minute increase in ARR, the odds of experiencing moderate-to-high stress increased by 1.230 or by 23.0% (p<0.01). Consistent with previous research, participants who did not identify as male (i.e., female, nonbinary, and transgender participants) had significantly higher self-reported stress throughout the study. The week of the semester was also a significant predictor of stress. Sleep data from wearable devices may help us understand and to better predict stress, a strong signal of the ongoing mental health epidemic among college students.

14.
Ecol Lett ; 16(5): 584-99, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23489285

RESUMO

Bees provide essential pollination services that are potentially affected both by local farm management and the surrounding landscape. To better understand these different factors, we modelled the relative effects of landscape composition (nesting and floral resources within foraging distances), landscape configuration (patch shape, interpatch connectivity and habitat aggregation) and farm management (organic vs. conventional and local-scale field diversity), and their interactions, on wild bee abundance and richness for 39 crop systems globally. Bee abundance and richness were higher in diversified and organic fields and in landscapes comprising more high-quality habitats; bee richness on conventional fields with low diversity benefited most from high-quality surrounding land cover. Landscape configuration effects were weak. Bee responses varied slightly by biome. Our synthesis reveals that pollinator persistence will depend on both the maintenance of high-quality habitats around farms and on local management practices that may offset impacts of intensive monoculture agriculture.


Assuntos
Agricultura , Abelhas/fisiologia , Ecossistema , Modelos Teóricos , Polinização , Animais , Clima , Produtos Agrícolas , Flores , Densidade Demográfica
15.
PLoS Biol ; 8(3): e1000331, 2010 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-20305712

RESUMO

Recent climate talks in Copenhagen reaffirmed the crucial role of reducing emissions from deforestation and degradation (REDD). Creating and strengthening indigenous lands and other protected areas represents an effective, practical, and immediate REDD strategy that addresses both biodiversity and climate crises at once.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Brasil , Conservação dos Recursos Naturais/legislação & jurisprudência , Ecossistema , Humanos , Cooperação Internacional/legislação & jurisprudência
16.
Ecol Appl ; 23(5): 1113-23, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23967579

RESUMO

Natural ecosystems benefit human communities by providing ecosystem services such as water purification and crop pollination. Mapping ecosystem service values has become popular, but most are static snapshots of average value. Estimating instead the economic impacts of specific ecosystem changes can better inform typical resource decisions. Here we develop an approach to mapping marginal values, those resulting from the next unit of ecosystem change, across landscapes. We demonstrate the approach with a recent model of crop pollination services in Costa Rica, simulating deforestation events to predict resulting marginal changes in pollination services to coffee farms. We find that marginal losses from deforestation vary from zero to US$700/ha across the landscape. Financial risks for farmers from these losses and marginal benefits of forest restoration show similar spatial variation. Marginal values are concentrated in relatively few forest parcels not identified using average value. These parcels lack substitutes: nearby forest parcels that can supply services in the event of loss. Indeed, the marginal value of forest parcels declines exponentially with the density of surrounding forest cover. The approach we develop is applicable to any ecosystem service. Combined with information on costs, it can help target conservation or restoration efforts to optimize benefits to people and biodiversity.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Polinização , Árvores , Clima Tropical , Agricultura/economia , Animais , Costa Rica , Monitoramento Ambiental , Humanos , Modelos Biológicos
17.
PLoS One ; 18(4): e0284631, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37075057

RESUMO

Most terrestrial angiosperms form mutualisms with both mycorrhizal fungi and animal pollinators. Yet, the effects of mycorrhizae on pollinator behavior and plant reproduction are unknown for most species, and whether the source or type of mycorrhizal fungi affects reproductive success has rarely been examined. We examined whether inoculating highbush blueberry (Vaccinium corymbosum; Ericaceae) with ericoid mycorrhizal fungi enhanced investment in flowering and attractiveness to pollinators, and thus reduced their levels of pollen limitation over that of non-inoculated plants. We also examined the degree to which pollen limitation was dependent on inoculation source and the surrounding pollinator community context. Three-year-old saplings of Vaccinium corymbosum 'Bluecrop' or highbush blueberry (Ericaceae) were inoculated with a) ericoid mycorrhizal fungi within soil of the rhizosphere of plants growing at a local blueberry farm, b) a commercially available ericoid inoculant, c) both the local soils and commercial inoculum, or d) were not inoculated and served as controls. They were grown for one year in pots in a common garden and, in the following year, were moved to six farms in central Vermont that were known from prior studies to differ in pollinator abundance and diversity. We conducted a hand pollination experiment at each farm to examine if inoculation or pollinator abundance (i.e., farm context) affected reproductive success. Plants treated with all types of inoculums were more likely to flower, and produced more inflorescence buds than non-inoculated plants in 2018. However, in 2019, plants in the combination inoculum treatment, alone, produced more inflorescence buds than those in the other treatments. Neither the source of inoculum nor hand pollination affected fruit set (the proportion of flowers setting fruit), or fruit sugar content. Hand pollination, but not inoculation, increased berry mass and the average number of seeds produced/berry. Our results add to the growing body of evidence that mycorrhizal fungi can affect reproductive traits of their hosts but that the effects of mycorrhizal fungi depend on the mycorrhizal symbionts.


Assuntos
Mirtilos Azuis (Planta) , Ericaceae , Micorrizas , Animais , Mirtilos Azuis (Planta)/microbiologia , Reprodução , Polinização , Simbiose , Solo , Plantas
18.
Contemp Clin Trials ; 133: 107338, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37722484

RESUMO

INTRODUCTION: The transition to college is a period of elevated risk for a range of mental health conditions. Although colleges and universities strive to provide mental health support to their students, the high demand for these services makes it difficult to provide scalable, cost-effective solutions. OBJECTIVE: To address these issues, the present study aims to compare the efficacy of three different treatments using a large cohort of 600 students transitioning to college. Interventions were selected based on their potential for generalizability and cost-effectiveness on college campuses. METHODS: The study is a Phase II parallel-group, four-arm, randomized controlled trial with 1:1 allocation that will assign 600 participants to one (n = 150 per condition) of four arms: 1) group-based therapy, 2) physical activity program, 3) nature experiences, or 4) weekly assessment condition as a control group. Physiological data will be collected from all participants using a wearable device to develop algorithmic mental and physical health functioning predictions. Once recruitment is complete, modeling strategies will be used to evaluate the outcomes and effectiveness of each intervention. DISCUSSION: The findings of this study will provide evidence as to the benefits of implementing scalable and proactive interventions using technology with the goal of improving the well-being and success of new college students.

19.
Nature ; 440(7081): 212-4, 2006 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-16382239

RESUMO

Understanding patterns of biodiversity distribution is essential to conservation strategies, but severe data constraints make surrogate measures necessary. For this reason, many studies have tested the performance of terrestrial vertebrates as surrogates for overall species diversity, but these tests have typically been limited to a single taxon or region. Here we show that global patterns of richness are highly correlated among amphibians, reptiles, birds and mammals, as are endemism patterns. Furthermore, we demonstrate that although the correlation between global richness and endemism is low, aggregate regions selected for high levels of endemism capture significantly more species than expected by chance. Although areas high in endemism have long been targeted for the protection of narrow-ranging species, our findings provide evidence that endemism is also a useful surrogate for the conservation of all terrestrial vertebrates.


Assuntos
Biodiversidade , Vertebrados/fisiologia , Animais , Conservação dos Recursos Naturais , Modelos Biológicos , Densidade Demográfica
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