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1.
Ecol Lett ; 26(6): 929-941, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37024278

RESUMO

Biodiversity loss and its effects on humanity is of major global concern. While a growing body of literature confirms positive relationships between biodiversity and multiple ecological functions, the links between biodiversity, ecological functions and multiple ecosystem services is yet unclear. Studies of biodiversity-functionality relationships are mainly based on computer simulations or controlled field experiments using only few species. Here, we use a trait-based approach to integrate plant functions into an ecosystem service assessment to address impacts of restoration on species-rich grasslands over time. We found trade-offs among functions and services when analysing contributions from individual species. At the community level, these trade-offs disappeared for almost all services with time since restoration as an effect of increased species diversity and more evenly distributed species. Restoration to enhance biodiversity also in species-rich communities is therefore essential to secure higher functional redundancy towards disturbances and sustainable provision of multiple ecosystem services over time.


Assuntos
Biodiversidade , Ecossistema , Simulação por Computador , Fenômenos Fisiológicos Vegetais , Pradaria
2.
Glob Chang Biol ; 22(12): 3948-3959, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27002684

RESUMO

Although it is generally recognized that global biodiversity is declining, few studies have examined long-term changes in multiple biodiversity dimensions simultaneously. In this study, we quantified and compared temporal changes in the abundance, taxonomic diversity, functional diversity, and phylogenetic diversity of bird assemblages, using roadside monitoring data of the North American Breeding Bird Survey from 1971 to 2010. We calculated 12 abundance and diversity metrics based on 5-year average abundances of 519 species for each of 768 monitoring routes. We did this for all bird species together as well as for four subgroups based on breeding habitat affinity (grassland, woodland, wetland, and shrubland breeders). The majority of the biodiversity metrics increased or remained constant over the study period, whereas the overall abundance of birds showed a pronounced decrease, primarily driven by declines of the most abundant species. These results highlight how stable or even increasing metrics of taxonomic, functional, or phylogenetic diversity may occur in parallel with substantial losses of individuals. We further found that patterns of change differed among the species subgroups, with both abundance and diversity increasing for woodland birds and decreasing for grassland breeders. The contrasting changes between abundance and diversity and among the breeding habitat groups underscore the relevance of a multifaceted approach to measuring biodiversity change. Our findings further stress the importance of monitoring the overall abundance of individuals in addition to metrics of taxonomic, functional, or phylogenetic diversity, thus confirming the importance of population abundance as an essential biodiversity variable.


Assuntos
Biodiversidade , Aves/classificação , Filogenia , Animais , Ecossistema , América do Norte
3.
Am J Bot ; 100(7): 1356-68, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23825137

RESUMO

PREMISE OF STUDY: Plant functional traits are commonly used as proxies for plant responses to environmental challenges, yet few studies have explored how functional trait distributions differ across gradients of land-use change. By comparing trait distributions in intact forests with those across land-use change gradients, we can improve our understanding of the ways land-use change alters the diversity and functioning of plant communities. METHODS: We examined how the variation and distribution of trait values for seven plant functional traits differ between reference natural forest and three types of land-use conversion (pasture, old-field, or "legacy" sites-regrowth following logging), landscape productivity (NPP) and vegetation strata (tree or non-tree "understory"), in a meta-analysis of studies from 15 landscapes across five continents. KEY RESULTS: Although trait variation often differed between land-uses within a landscape, these patterns were rarely consistent across landscapes. The variance and distribution of traits were more likely to differ consistently between natural forest and land-use conversion categories for understory (non-tree) plants than for trees. Landscape productivity did not significantly alter the difference in trait variance between natural forest and land-use conversion categories for any trait except dispersal. CONCLUSIONS: Our results suggest that even for traits well linked to plant environmental response strategies, broad classes of land-use change and landscape productivity are not generally useful indicators of the mechanisms driving compositional changes in human-modified forest systems.


Assuntos
Ecossistema , Fenômenos Fisiológicos Vegetais , Árvores/fisiologia , Demografia , Monitoramento Ambiental
4.
Nat Food ; 4(1): 22-29, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37118580

RESUMO

Despite the growing knowledge that food system solutions should account for interactions and drivers across scales, broader societal debate on how to solve food system challenges is often focused on two dichotomous perspectives and associated solutions: either more localized food systems or greater global coordination of food systems. The debate has found problematic expressions in contemporary challenges, prompting us to revisit the role that resilience thinking can play when faced with complex crises that increase uncertainty. Here we identify four 'aching points' facing food systems that are central points of tension in the local-global debate. We apply the seven principles of resilience to these aching points to reframe the solution space to one that embeds resilience into food systems' management and governance at all scales, supporting transformative change towards sustainable food systems.


Assuntos
Alimentos , Lentes , Incerteza
5.
Ambio ; 50(2): 314-331, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32948985

RESUMO

The ecosystem service concept is recognized as a useful tool to support sustainability in decision-making. In this study, we collaborated with actors in the Helge å catchment, southern Sweden, in an iterative participatory ecosystem service assessment. Through workshops and interviews, we jointly decided which ecosystem services to assess and indicators to use in order to achieve a sense of ownership and a higher legitimacy of the assessment. Subsequently, we explored the landscape-level interactions between the 15 assessed services, and found that the area can be described using three distinct ecosystem service bundles. The iterative, participatory process strengthened our analysis and created a shared understanding and overview of the multifunctional landscape around Helge å among participants. Importantly, this allowed for the generated knowledge to impact local strategic sustainability planning. With this study, we illustrate how similar processes can support local decision-making for a more sustainable future.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Propriedade , Suécia
6.
Curr Cardiol Rev ; 17(5): e190721189769, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33390145

RESUMO

INTRODUCTION: Coronary artery disease (CAD) represents approximately 390 thousand deaths per year in Brazil and is associated, among other predictors, with the use of anabolic and androgenic steroids (AAS). OBJECTIVE: To analyze a clinical case of a patient who suffered AMI after abuse of AAS. A systematic literature review has been carried out to physiologically analyze the main factors that can lead to AMI with the use of these hormones. METHODS: The EVR patient, 41 years old, denies any comorbidities or use of medications. He has been admitted to the emergency room due to typical angina-precordial pain in tightness associated with eventual back pain and paresthesia of both upper limbs, after intense physical effort at the gym, without improvement at rest, and with partial improvement after first care at the health unit. The patient was hypertensive in an emergency bed after the occurrence of ST elevation. The patient alleges the use of anabolic steroids for one month. The patient presented with obstructive atherosclerotic coronary artery disease with total occlusion of the anterior descending artery. Systematic review: A total of 89 clinical studies have been compared and submitted to eligibility analysis, with 50 studies selected, according to the PRISMA rules. RESULTS: Long-term consumption of AAS may cause pathological changes, however, AAS can increase protein synthesis, muscle growth, and erythropoiesis. CONCLUSION: Abuse of AAS has a toxic cardiovascular effect, which significantly increases the incidence of cardiovascular diseases.


Assuntos
Anabolizantes , Doenças Cardiovasculares , Sistema Cardiovascular , Adulto , Anabolizantes/efeitos adversos , Humanos , Masculino , Esteroides , Congêneres da Testosterona/efeitos adversos
7.
Ecol Lett ; 13(1): 76-86, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19917052

RESUMO

Ecosystem resilience depends on functional redundancy (the number of species contributing similarly to an ecosystem function) and response diversity (how functionally similar species respond differently to disturbance). Here, we explore how land-use change impacts these attributes in plant communities, using data from 18 land-use intensity gradients that represent five biomes and > 2800 species. We identify functional groups using multivariate analysis of plant traits which influence ecosystem processes. Functional redundancy is calculated as the species richness within each group, and response diversity as the multivariate within-group dispersion in response trait space, using traits that influence responses to disturbances. Meta-analysis across all datasets showed that land-use intensification significantly reduced both functional redundancy and response diversity, although specific relationships varied considerably among the different land-use gradients. These results indicate that intensified management of ecosystems for resource extraction can increase their vulnerability to future disturbances.


Assuntos
Agricultura , Biodiversidade , Fenômenos Fisiológicos Vegetais , Bases de Dados Factuais , Modelos Biológicos , Dinâmica Populacional
8.
Cardiol Res ; 9(2): 75-82, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29755623

RESUMO

The mortality rate of post-infarction cardiogenic shock (CS) was 80.0-90.0%. Recent studies show a significant reduction of hospital mortality to approximately 50.0%. CS is defined as systemic tissue hypoperfusion resulting from systolic and/or diastolic heart dysfunction, the main cause of which is acute myocardial infarction (AMI). The main predictors are biological markers such as troponin, CKMB and lactate. A systematic literature review and meta-analysis is performed in order to present and correlate the main literary findings on CS and its evolution with possible changes in biomarkers such as troponin, lactate and CKMB. After criteria of literary search with the use of the mesh terms: cardiogenic shock; acute myocardial infarction; biomarkers; troponin; CKMB; lactate; clinical trials and use of the bouleanos "and" between the mesh terms and "or" among the historical findings. In the main databases such as Pubmed, Medline, Bireme, EBSCO, Scielo, etc., a total of 96 papers that were submitted to the eligibility analysis were collated and, after that, 41 studies were selected, following the rules of systematic review - PRISMA (Transparent reporting of systematic reviews and meta-analyzes-http://www.prisma-statement.org/). Some risk factors for its development in AMI are advanced age, female gender, anterior wall infarction, diabetes mellitus, systemic arterial hypertension, previous history of infarction and angina. The CS associated with AMI depends on its extent and its complications, being the main ones: mitral regurgitation, rupture of the interventricular septum and rupture of the free wall of the left ventricule. The diagnosis is based on the clinical manifestations, such as mental confusion, oliguria, hypotension, tachycardia, fine pulse, sweating, and cold extremities; in hemodynamic aspects: systolic blood pressure was < 90.0 mm Hg or 30 mm Hg below baseline, pulmonary capillary pressure was > 18.0 mm Hg and cardiac index was < 2.2 L/min/m2. Laboratory and imaging exams should be requested to evaluate the possible etiology of CS, its systemic repercussions and comorbidities. The treatment aims at the rapid reestablishment of the blood flow in the affected artery, to improve the patient's prognosis. The biomarkers dosage in the daily clinical practice of the different cardiological centers can facilitate the diagnosis and the conduction of the dubious cases and the best evaluation of the degree of myocardial suffering after CS.

11.
Ambio ; 44 Suppl 1: S89-101, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25576284

RESUMO

Ecosystem services (ES) is a valuable concept to be used in the planning and management of social-ecological landscapes. However, the understanding of the determinant factors affecting the interaction between services in the form of synergies or trade-offs is still limited. We assessed the production of 16 ES across 62 municipalities in the Norrström drainage basin in Sweden. We combined GIS data with publically available information for quantifying and mapping the distribution of services. Additionally, we calculated the diversity of ES for each municipality and used correlations and k-means clustering analyses to assess the existence of ES bundles. We found five distinct types of bundles of ES spatially agglomerated in the landscape that could be explained by regional social and ecological gradients. Human-dominated landscapes were highly multifunctional in our study area and urban densely populated areas were hotspots of cultural services.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Ecologia , Suécia
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