Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Glob Chang Biol ; 28(8): 2622-2638, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35007364

RESUMO

Understanding how evolutionary history and the coordination between trait trade-off axes shape the drought tolerance of trees is crucial to predict forest dynamics under climate change. Here, we compiled traits related to drought tolerance and the fast-slow and stature-recruitment trade-off axes in 601 tropical woody species to explore their covariations and phylogenetic signals. We found that xylem resistance to embolism (P50) determines the risk of hydraulic failure, while the functional significance of leaf turgor loss point (TLP) relies on its coordination with water use strategies. P50 and TLP exhibit weak phylogenetic signals and substantial variation within genera. TLP is closely associated with the fast-slow trait axis: slow species maintain leaf functioning under higher water stress. P50 is associated with both the fast-slow and stature-recruitment trait axes: slow and small species exhibit more resistant xylem. Lower leaf phosphorus concentration is associated with more resistant xylem, which suggests a (nutrient and drought) stress-tolerance syndrome in the tropics. Overall, our results imply that (1) drought tolerance is under strong selective pressure in tropical forests, and TLP and P50 result from the repeated evolutionary adaptation of closely related taxa, and (2) drought tolerance is coordinated with the ecological strategies governing tropical forest demography. These findings provide a physiological basis to interpret the drought-induced shift toward slow-growing, smaller, denser-wooded trees observed in the tropics, with implications for forest restoration programmes.


Assuntos
Secas , Xilema , Florestas , Filogenia , Folhas de Planta/fisiologia , Clima Tropical , Madeira
2.
Glob Food Sec ; 23: 191-204, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31799110

RESUMO

•Unique dataset allows analysis of urban Indian shopping habits of processed foods.•Beyond staples, purchases of processed foods and beverages for home use are low.•Fastest rate of growth seen in sweet and salty snacks, and edible oil purchases.•Highest volume of processed foods and beverages purchased by Delhi population.•Large variations across states in level and trends of purchases over time.

3.
PLoS One ; 14(5): e0216698, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31141538

RESUMO

Methods of reconstructing changes in plant traits over long time scales are needed to understand the impact of changing environmental conditions on ecosystem processes and services. Although Holocene pollen have been extensively used to provide records of vegetation history, few studies have adopted a functional trait approach that is pertinent to changes in ecosystem processes. Here, for woody and herbaceous fen peatland communities, we use modern pollen and vegetation data combined with pollen records from Holocene deposits to reconstruct vegetation functional dynamics. The six traits chosen (measures of leaf area-to-mass ratio and leaf nutrient content) are known to modulate species' fitness and to vary with changes in ecosystem processes. We fitted linear mixed effects models between community weighted mean (CWM) trait values of the modern pollen and vegetation to determine whether traits assigned to pollen types could be used to reconstruct traits found in the vegetation from pollen assemblages. We used relative pollen productivity (RPP) correction factors in an attempt to improve this relationship. For traits showing the best fit between modern pollen and vegetation, we applied the model to dated Holocene pollen sequences from Fenland and Romney Marsh in eastern and southern England and reconstructed temporal changes in trait composition. RPP adjustment did not improve the linear relationship between modern pollen and vegetation. Leaf nutrient traits (leaf C and N) were generally more predictable from pollen data than mass-area traits. We show that inferences about biomass accumulation and decomposition rates can be made using Holocene trait reconstructions. While it is possible to reconstruct community-level trends for some leaf traits from pollen assemblages preserved in sedimentary archives in wetlands, we show the importance of testing methods in modern systems first and encourage further development of this approach to address issues concerning the pollen-plant abundance relationship and pollen source area.


Assuntos
Coleta de Dados/métodos , Folhas de Planta/química , Pólen/classificação , Biodiversidade , Evolução Biológica , Biomassa , Análise de Dados , Ecossistema , Inglaterra , Modelos Teóricos , Fenótipo , Plantas , Pólen/química , Pólen/metabolismo , Análise Espaço-Temporal , Áreas Alagadas
4.
Sustainability ; 11(23): 6575, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-39035350

RESUMO

Global food systems are currently challenged by unsustainable and unhealthy consumption and production practices. Food labelling provides information on key characteristics of food items, thereby potentially driving more sustainable food choices or demands. This review explores how consumers value three different elements of sustainable diets: Comparing consumer response to nutrition information on food labels against environmental and/or social responsibility information. Six databases were systematically searched for studies examining consumer choice/preference/evaluation of nutrition against environmental and/or social responsibility attributes on food labels. Studies were quality assessed against domain-based criteria and reported using PRISMA guidelines. Thirty articles with 19,040 participants met inclusion criteria. Study quality was mixed, with samples biased towards highly-educated females. Environmental and social responsibility attributes were preferred to nutrition attributes in 17 studies (11 environmental and six social), compared to nine where nutrition attributes were valued more highly. Three studies found a combination of attributes were valued more highly than either attribute in isolation. One study found no significant preference. The most preferred attribute was organic labelling, with a health inference likely. Consumers generally have a positive view of environmental and social responsibility food labelling schemes. Combination labelling has potential, with a mix of sustainable diet attributes appearing well-received.

5.
Proc Natl Acad Sci U S A ; 114(51): E10937-E10946, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29196525

RESUMO

Our ability to understand and predict the response of ecosystems to a changing environment depends on quantifying vegetation functional diversity. However, representing this diversity at the global scale is challenging. Typically, in Earth system models, characterization of plant diversity has been limited to grouping related species into plant functional types (PFTs), with all trait variation in a PFT collapsed into a single mean value that is applied globally. Using the largest global plant trait database and state of the art Bayesian modeling, we created fine-grained global maps of plant trait distributions that can be applied to Earth system models. Focusing on a set of plant traits closely coupled to photosynthesis and foliar respiration-specific leaf area (SLA) and dry mass-based concentrations of leaf nitrogen ([Formula: see text]) and phosphorus ([Formula: see text]), we characterize how traits vary within and among over 50,000 [Formula: see text]-km cells across the entire vegetated land surface. We do this in several ways-without defining the PFT of each grid cell and using 4 or 14 PFTs; each model's predictions are evaluated against out-of-sample data. This endeavor advances prior trait mapping by generating global maps that preserve variability across scales by using modern Bayesian spatial statistical modeling in combination with a database over three times larger than that in previous analyses. Our maps reveal that the most diverse grid cells possess trait variability close to the range of global PFT means.


Assuntos
Ecossistema , Plantas , Característica Quantitativa Herdável , Meio Ambiente , Geografia , Modelos Estatísticos , Dispersão Vegetal , Análise Espacial
6.
Nutrients ; 8(3): 137, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26950149

RESUMO

This study is part of the research undertaken in the EU funded project CLYMBOL ("Role of health-related CLaims and sYMBOLs in consumer behaviour"). The first phase of this project consisted of mapping the prevalence of symbolic and non-symbolic nutrition and health-related claims (NHC) on foods and non-alcoholic beverages in five European countries. Pre-packaged foods and drinks were sampled based on a standardized sampling protocol, using store lists or a store floor plan. Data collection took place across five countries, in three types of stores. A total of 2034 foods and drinks were sampled and packaging information was analyzed. At least one claim was identified for 26% (95% CI (24.0%-27.9%)) of all foods and drinks sampled. Six percent of these claims were symbolic. The majority of the claims were nutrition claims (64%), followed by health claims (29%) and health-related ingredient claims (6%). The most common health claims were nutrient and other function claims (47% of all claims), followed by disease risk reduction claims (5%). Eight percent of the health claims were children's development and health claims but these were only observed on less than 1% (0.4%-1.1%) of the foods. The category of foods for specific dietary use had the highest proportion of NHC (70% of foods carried a claim). The prevalence of symbolic and non-symbolic NHC varies across European countries and between different food categories. This study provides baseline data for policy makers and the food industry to monitor and evaluate the use of claims on food packaging.


Assuntos
Bebidas , Fast Foods , Rotulagem de Alimentos/legislação & jurisprudência , Alimentos Orgânicos , Promoção da Saúde/legislação & jurisprudência , Idioma , Legislação sobre Alimentos , Valor Nutritivo , Compreensão , Comportamento do Consumidor , Estudos Transversais , Europa (Continente) , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos
7.
PLoS One ; 10(4): e0122721, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25856241

RESUMO

Climate and land cover change are driving a major reorganization of terrestrial biotic communities in tropical ecosystems. In an effort to understand how biodiversity patterns in the tropics will respond to individual and combined effects of these two drivers of environmental change, we use species distribution models (SDMs) calibrated for recent climate and land cover variables and projected to future scenarios to predict changes in diversity patterns in Madagascar. We collected occurrence records for 828 plant genera and 2186 plant species. We developed three scenarios, (i.e., climate only, land cover only and combined climate-land cover) based on recent and future climate and land cover variables. We used this modelling framework to investigate how the impacts of changes to climate and land cover influenced biodiversity across ecoregions and elevation bands. There were large-scale climate- and land cover-driven changes in plant biodiversity across Madagascar, including both losses and gains in diversity. The sharpest declines in biodiversity were projected for the eastern escarpment and high elevation ecosystems. Sharp declines in diversity were driven by the combined climate-land cover scenarios; however, there were subtle, region-specific differences in model outputs for each scenario, where certain regions experienced relatively higher species loss under climate or land cover only models. We strongly caution that predicted future gains in plant diversity will depend on the development and maintenance of dispersal pathways that connect current and future suitable habitats. The forecast for Madagascar's plant diversity in the face of future environmental change is worrying: regional diversity will continue to decrease in response to the combined effects of climate and land cover change, with habitats such as ericoid thickets and eastern lowland and sub-humid forests particularly vulnerable into the future.


Assuntos
Biodiversidade , Mudança Climática , Ecossistema , Modelos Biológicos , Dispersão Vegetal , Plantas/genética , Algoritmos , Geografia , Madagáscar , Dinâmica Populacional , Clima Tropical
8.
Public Health Nutr ; 18(8): 1378-88, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25246004

RESUMO

OBJECTIVE: Transparent evidence-based decision making has been promoted worldwide to engender trust in science and policy making. Yet, little attention has been given to transparency implementation. The degree of transparency (focused on how uncertain evidence was handled) during the development of folate and vitamin D Dietary Reference Values was explored in three a priori defined areas: (i) value request; (ii) evidence evaluation; and (iii) final values. DESIGN: Qualitative case studies (semi-structured interviews and desk research). A common protocol was used for data collection, interview thematic analysis and reporting. Results were coordinated via cross-case synthesis. SETTING: Australia and New Zealand, Netherlands, Nordic countries, Poland, Spain and UK. SUBJECTS: Twenty-one interviews were conducted in six case studies. RESULTS: Transparency of process was not universally observed across countries or areas of the recommendation setting process. Transparency practices were most commonly seen surrounding the request to develop reference values (e.g. access to risk manager/assessor problem formulation discussions) and evidence evaluation (e.g. disclosure of risk assessor data sourcing/evaluation protocols). Fewer transparency practices were observed to assist with handling uncertainty in the evidence base during the development of quantitative reference values. CONCLUSIONS: Implementation of transparency policies may be limited by a lack of dedicated resources and best practice procedures, particularly to assist with the latter stages of reference value development. Challenges remain regarding the best practice for transparently communicating the influence of uncertain evidence on the final reference values. Resolving this issue may assist the evolution of nutrition risk assessment and better inform the recommendation setting process.


Assuntos
Ácido Fólico/administração & dosagem , Política Nutricional , Recomendações Nutricionais , Incerteza , Vitamina D/administração & dosagem , Austrália , Tomada de Decisões , Dieta , Medicina Baseada em Evidências , Humanos , Países Baixos , Nova Zelândia , Polônia , Formulação de Políticas , Pesquisa Qualitativa , Países Escandinavos e Nórdicos , Espanha
9.
Crit Rev Food Sci Nutr ; 53(10): 999-1040, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23952085

RESUMO

The EURopean micronutrient RECommendations Aligned (EURRECA) Network of Excellence explored the process of setting micronutrient recommendations to address the variance in recommendations across Europe. Work centered upon the transparent assessment of nutritional requirements via a series of systematic literature reviews and meta-analyses. In addition, the necessity of assessing nutritional requirements and the policy context of setting micronutrient recommendations was investigated. Findings have been presented in a framework that covers nine activities clustered into four stages: stage one "Defining the problem" describes Activities 1 and 2: "Identifying the nutrition-related health problem" and "Defining the process"; stage two "Monitoring and evaluating" describes Activities 3 and 7: "Establishing appropriate methods," and "Nutrient intake and status of population groups"; stage three "Deriving dietary reference values" describes Activities 4, 5, and 6: "Collating sources of evidence," "Appraisal of the evidence," and "Integrating the evidence"; stage four "Using dietary reference values in policy making" describes Activities 8 and 9: "Identifying policy options," and "Evaluating policy implementation." These activities provide guidance on how to resolve various issues when deriving micronutrient requirements and address the methodological and policy decisions, which may explain the current variation in recommendations across Europe. [Supplementary materials are available for this article. Go to the publisher's online edition of Critical Reviews in Food Science and Nutrition for the following free supplemental files: Additional text, tables, and figures.].


Assuntos
Medicina Baseada em Evidências/métodos , Micronutrientes/normas , Política Nutricional/legislação & jurisprudência , Recomendações Nutricionais/legislação & jurisprudência , Biomarcadores/sangue , Tomada de Decisões , Dieta/normas , Ingestão de Energia , Europa (Continente) , Humanos , Metanálise como Assunto , Modelos Biológicos , Avaliação Nutricional , Estado Nutricional , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Valores de Referência , Medição de Risco , Fatores Socioeconômicos
10.
Crit Rev Food Sci Nutr ; 53(10): 1124-34, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23952092

RESUMO

A key step toward developing appropriate evidence-based public health nutrition policies is determining exactly how that evidence should be collected and assessed. Despite this the extent to which different evidence bases influence policy selection is rarely explored. This article presents an epistemological framework which offers a range of considerations affecting this process generally and with particular implications for both micronutrient requirements and the role of behavior in the policy-making process. Qualitative case study data covering 6 European countries/regions (Czech Republic, Italy, the Netherlands, Nordic countries, Poland, and Spain), and three micronutrients (folate, iodine, and vitamin D), have been presented to illustrate the relevance of the Framework.


Assuntos
Política Nutricional/legislação & jurisprudência , Formulação de Políticas , Saúde Pública , Recomendações Nutricionais/legislação & jurisprudência , Suplementos Nutricionais , Europa (Continente) , Medicina Baseada em Evidências , Humanos , Metanálise como Assunto , Micronutrientes/sangue , Estado Nutricional
11.
Public Health Nutr ; 16(5): 769-76, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23182406

RESUMO

OBJECTIVE: The involvement of consumers in the development of dietary guidelines has been promoted by national and international bodies. Yet, few best practice guidelines have been established to assist with such involvement. DESIGN: Qualitative semi-structured interviews explored stakeholders' beliefs about consumer involvement in dietary guideline development. SETTING: Interviews were conducted in six European countries: the Czech Republic, Germany, Norway, Serbia, Spain and the UK. SUBJECTS: Seventy-seven stakeholders were interviewed. Stakeholders were grouped as government, scientific advisory body, professional and academic, industry or non-government organisations. Response rate ranged from 45 % to 95 %. RESULTS: Thematic analysis was conducted with the assistance of NVivo qualitative software. Analysis identified two main themes: (i) type of consumer involvement and (ii) pros and cons of consumer involvement. Direct consumer involvement (e.g. consumer organisations) in the decision-making process was discussed as a facilitator to guideline communication towards the end of the process. Indirect consumer involvement (e.g. consumer research data) was considered at both the beginning and the end of the process. Cons to consumer involvement included the effect of vested interests on objectivity; consumer disinterest; and complications in terms of time, finance and technical understanding. Pros related to increased credibility and trust in the process. CONCLUSIONS: Stakeholders acknowledged benefits to consumer involvement during the development of dietary guidelines, but remained unclear on the advantage of direct contributions to the scientific content of guidelines. In the absence of established best practice, clarity on the type and reasons for consumer involvement would benefit all actors.


Assuntos
Participação da Comunidade , Dieta/normas , Guias como Assunto , Recomendações Nutricionais , República Tcheca , Tomada de Decisões , Alemanha , Humanos , Noruega , Sérvia , Espanha , Reino Unido
12.
Appetite ; 58(3): 1014-22, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22407133

RESUMO

The objective of this study was to relate behaviour change mechanisms to nutritionally relevant behaviour and demonstrate how the different mechanisms can affect attempts to change these behaviours. Folate was used as an example to illuminate the possibilities and challenges in inducing behaviour change. The behaviours affecting folate intake were recognised and categorised. Behaviour change mechanisms from "rational model of man", behavioural economics, health psychology and social psychology were identified and aligned against folate-related behaviours. The folate example demonstrated the complexity of mechanisms influencing possible behavioural changes, even though this only targets the intake of a single micronutrient. When considering possible options to promote folate intake, the feasibility of producing the desired outcome should be related to the mechanisms of required changes in behaviour and the possible alternatives that require no or only minor changes in behaviour. Dissecting the theories provides new approaches to food-related behaviour that will aid the development of batteries of policy options when targeting nutritional problems.


Assuntos
Dieta , Comportamento Alimentar , Ácido Fólico/administração & dosagem , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Micronutrientes/administração & dosagem , Feminino , Humanos , Masculino , Modelos Psicológicos , Gravidez , Teoria Psicológica
13.
PLoS One ; 6(9): e24107, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21909413

RESUMO

Biodiversity plays an integral role in the livelihoods of subsistence-based forest-dwelling communities and as a consequence it is increasingly important to develop quantitative approaches that capture not only changes in taxonomic diversity, but also variation in natural resources and provisioning services. We apply a functional diversity metric originally developed for addressing questions in community ecology to assess utilitarian diversity of 56 forest plots in Madagascar. The use categories for utilitarian plants were determined using expert knowledge and household questionnaires. We used a null model approach to examine the utilitarian (functional) diversity and utilitarian redundancy present within ecological communities. Additionally, variables that might influence fluctuations in utilitarian diversity and redundancy--specifically number of felled trees, number of trails, basal area, canopy height, elevation, distance from village--were analyzed using Generalized Linear Models (GLMs). Eighteen of the 56 plots showed utilitarian diversity values significantly higher than expected. This result indicates that these habitats exhibited a low degree of utilitarian redundancy and were therefore comprised of plants with relatively distinct utilitarian properties. One implication of this finding is that minor losses in species richness may result in reductions in utilitarian diversity and redundancy, which may limit local residents' ability to switch between alternative choices. The GLM analysis showed that the most predictive model included basal area, canopy height and distance from village, which suggests that variation in utilitarian redundancy may be a result of local residents harvesting resources from the protected area. Our approach permits an assessment of the diversity of provisioning services available to local communities, offering unique insights that would not be possible using traditional taxonomic diversity measures. These analyses introduce another tool available to conservation biologists for assessing how future losses in biodiversity will lead to a reduction in natural resources and provisioning services from forests.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Características de Residência , Árvores/crescimento & desenvolvimento , Geografia , Modelos Lineares , Madagáscar , Modelos Biológicos , Especificidade da Espécie
14.
PLoS One ; 6(5): e20583, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21637787

RESUMO

Two of the major limitations to effective management of coral reef ecosystems are a lack of information on the spatial distribution of marine species and a paucity of data on the interacting environmental variables that drive distributional patterns. Advances in marine remote sensing, together with the novel integration of landscape ecology and advanced niche modelling techniques provide an unprecedented opportunity to reliably model and map marine species distributions across many kilometres of coral reef ecosystems. We developed a multi-scale approach using three-dimensional seafloor morphology and across-shelf location to predict spatial distributions for five common Caribbean fish species. Seascape topography was quantified from high resolution bathymetry at five spatial scales (5-300 m radii) surrounding fish survey sites. Model performance and map accuracy was assessed for two high performing machine-learning algorithms: Boosted Regression Trees (BRT) and Maximum Entropy Species Distribution Modelling (MaxEnt). The three most important predictors were geographical location across the shelf, followed by a measure of topographic complexity. Predictor contribution differed among species, yet rarely changed across spatial scales. BRT provided 'outstanding' model predictions (AUC = >0.9) for three of five fish species. MaxEnt provided 'outstanding' model predictions for two of five species, with the remaining three models considered 'excellent' (AUC = 0.8-0.9). In contrast, MaxEnt spatial predictions were markedly more accurate (92% map accuracy) than BRT (68% map accuracy). We demonstrate that reliable spatial predictions for a range of key fish species can be achieved by modelling the interaction between the geographical location across the shelf and the topographic heterogeneity of seafloor structure. This multi-scale, analytic approach is an important new cost-effective tool to accurately delineate essential fish habitat and support conservation prioritization in marine protected area design, zoning in marine spatial planning, and ecosystem-based fisheries management.


Assuntos
Biodiversidade , Recifes de Corais , Peixes/crescimento & desenvolvimento , Modelos Biológicos , Algoritmos , Animais , Área Sob a Curva , Região do Caribe , Geografia , Oceanos e Mares , Porto Rico , Análise de Regressão , Especificidade da Espécie
15.
Br J Nutr ; 106(1): 15-26, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21385508

RESUMO

Food-based dietary guidelines (FBDG) have primarily been designed for the consumer to encourage healthy, habitual food choices, decrease chronic disease risk and improve public health. However, minimal research has been conducted to evaluate whether FBDG are utilised by the public. The present review used a framework of three concepts, awareness, understanding and use, to summarise consumer evidence related to national FBDG and food guides. Searches of nine electronic databases, reference lists and Internet grey literature elicited 939 articles. Predetermined exclusion criteria selected twenty-eight studies for review. These consisted of qualitative, quantitative and mixed study designs, non-clinical participants, related to official FBDG for the general public, and involved measures of consumer awareness, understanding or use of FBDG. The three concepts of awareness, understanding and use were often discussed interchangeably. Nevertheless, a greater amount of evidence for consumer awareness and understanding was reported than consumer use of FBDG. The twenty-eight studies varied in terms of aim, design and method. Study quality also varied with raw qualitative data, and quantitative method details were often omitted. Thus, the reliability and validity of these review findings may be limited. Further research is required to evaluate the efficacy of FBDG as a public health promotion tool. If the purpose of FBDG is to evoke consumer behaviour change, then the framework of consumer awareness, understanding and use of FBDG may be useful to categorise consumer behaviour studies and complement the dietary survey and health outcome data in the process of FBDG evaluation and revision.


Assuntos
Alimentos , Conhecimentos, Atitudes e Prática em Saúde , Política Nutricional , Ciências da Nutrição , Análise de Alimentos/estatística & dados numéricos , Humanos
16.
Environ Manage ; 44(1): 136-48, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19224275

RESUMO

Despite their prevalence in both developed and developing countries, there have been surprisingly few field assessments of the ecological effectiveness of protected areas. This study aimed to assess the effectiveness of a key protected area in eastern Madagascar, Ranomafana National Park (RNP). We established paired 100 x 4-m vegetation transects (400 m(2)) within RNP and in remnant forests in the park's peripheral zone. In each 400-m(2) plot, all woody stems >1.5 cm in diameter at breast height were measured and identified to species. All species were also identified as native or non-native. We identified utilitarian species within all transects and they were sorted into use category. We calculated plot-level taxonomic biodiversity and functional diversity of utilitarian species; the latter was calculated by clustering the multivariate distances between species based on their utilitarian traits, and all metrics were tested using paired t-tests. Our results showed that there was significantly higher biodiversity inside RNP than in remnant forests and this pattern was consistent across all diversity metrics examined. Forests not located within the park's boundary had significantly higher non-native species than within RNP. There was no statistically significant difference in functional diversity of utilitarian species inside RNP vs. remnant forests; however, the overall trend was toward higher diversity inside park boundaries. These findings suggested that RNP has been effective at maintaining taxonomic diversity relative to surrounding unprotected areas and restricting the spread of non-native plants. The results also suggested that low functional redundancy of forests outside of RNP might be of concern, because residents in surrounding villages may have few other substitutes for the services provided by species that are of critical importance to their livelihoods. This study highlights the challenges of trying to reconcile biodiversity conservation with human use of natural resources in economically poor, remote areas.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Plantas/classificação , Árvores/classificação , Ecossistema , Madagáscar , Desenvolvimento Vegetal , Árvores/crescimento & desenvolvimento
17.
Appetite ; 50(2-3): 252-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17804116

RESUMO

This paper aimed to investigate which parents use which types of parenting control practices to manage their children's diets and to assess the impact of these practices on children's dietary patterns and their BMI. A cross-sectional survey of 518 parents with children aged 4-7 years was carried out in 18 primary schools across the South of England. Measures included aspects of parental control practices and the child's diet. Results showed that older parents with a lower BMI and who were stay at home parents used more "snack overt control", "snack covert control" and "meal covert control" and those with more education used more covert control strategies. In contrast, male, non-white parents with younger children used more "pressure to eat". In terms of the children's diet, the results showed links between parental and child demographics and aspects of unhealthy and healthy food intake. In addition, links were also found for parental control practices. For example, eating more unhealthy snacks was related to less covert control and more pressure to eat, eating fruit and vegetables was related to higher levels of both overt and covert control over meals and less pressure to eat and being neophobic was related to less covert control over meals and more pressure to eat. The children's BMIs were unrelated to any variables measured in the study.


Assuntos
Índice de Massa Corporal , Dieta , Ingestão de Alimentos/psicologia , Relações Pais-Filho , Poder Familiar/psicologia , Adulto , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Estudos Transversais , Ingestão de Energia , Inglaterra , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Sobrepeso/prevenção & controle , Sobrepeso/psicologia , Psicologia da Criança , Meio Social
18.
Proc Natl Acad Sci U S A ; 101(16): 6045-9, 2004 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-15067121

RESUMO

Ecological perturbations can either be necessary for maintaining tropical forest diversity or responsible for its decline, depending on the scale, nature, and frequency of the disturbance. Anthropogenic disturbances such as logging and subsistence agriculture may promote the establishment of nonnative, invasive plant species, potentially affecting forest structure and diversity even long after the perturbation has ceased. We investigated the impacts of logging 50 and 150 years ago on tropical forest vegetation in Madagascar, a "hotspot" of biodiversity. Logging was the overriding factor influencing establishment of nonnative plants. Sites once logged never recovered native species diversity because of the dominance and persistence of invasive species.


Assuntos
Árvores , Madagáscar , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...