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1.
Glob Chang Biol ; 22(6): 2106-24, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26683241

RESUMO

Accurate ground-based estimation of the carbon stored in terrestrial ecosystems is critical to quantifying the global carbon budget. Allometric models provide cost-effective methods for biomass prediction. But do such models vary with ecoregion or plant functional type? We compiled 15 054 measurements of individual tree or shrub biomass from across Australia to examine the generality of allometric models for above-ground biomass prediction. This provided a robust case study because Australia includes ecoregions ranging from arid shrublands to tropical rainforests, and has a rich history of biomass research, particularly in planted forests. Regardless of ecoregion, for five broad categories of plant functional type (shrubs; multistemmed trees; trees of the genus Eucalyptus and closely related genera; other trees of high wood density; and other trees of low wood density), relationships between biomass and stem diameter were generic. Simple power-law models explained 84-95% of the variation in biomass, with little improvement in model performance when other plant variables (height, bole wood density), or site characteristics (climate, age, management) were included. Predictions of stand-based biomass from allometric models of varying levels of generalization (species-specific, plant functional type) were validated using whole-plot harvest data from 17 contrasting stands (range: 9-356 Mg ha(-1) ). Losses in efficiency of prediction were <1% if generalized models were used in place of species-specific models. Furthermore, application of generalized multispecies models did not introduce significant bias in biomass prediction in 92% of the 53 species tested. Further, overall efficiency of stand-level biomass prediction was 99%, with a mean absolute prediction error of only 13%. Hence, for cost-effective prediction of biomass across a wide range of stands, we recommend use of generic allometric models based on plant functional types. Development of new species-specific models is only warranted when gains in accuracy of stand-based predictions are relatively high (e.g. high-value monocultures).


Assuntos
Biomassa , Ecossistema , Modelos Biológicos , Árvores/crescimento & desenvolvimento , Austrália , Carbono , Sequestro de Carbono , Eucalyptus/crescimento & desenvolvimento , Florestas , Caules de Planta/crescimento & desenvolvimento , Madeira/crescimento & desenvolvimento
3.
PLoS One ; 17(11): e0278043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36445918

RESUMO

Scientific teams are increasingly diverse in discipline, international scope and demographics. Diversity has been found to be a driver of innovation but also can be a source of interpersonal friction. Drawing on a mixed-method study of 22 scientific working groups, this paper presents evidence that team diversity has a positive impact on scientific output (i.e., the number of journal papers and citations) through the mediation of the interdisciplinarity of the collaborative process, as evidenced by publishing in and citing more diverse sources. Ironically these factors also seem to be related to lower team member satisfaction and perceived effectiveness, countered by the gender balance of the team. Qualitative data suggests additional factors that facilitate collaboration, such as trust and leadership. Our findings have implications for team design and management, as team diversity seems beneficial, but the process of integration can be difficult and needs management to lead to a productive and innovative process.


Assuntos
Confiabilidade dos Dados , Estudos Interdisciplinares , Fricção , Liderança , Editoração
4.
Biodivers Data J ; (6): e28073, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30473618

RESUMO

This paper discusses the process of retrieval and updating legacy data to allow on-line discovery and delivery. There are many pitfalls of institutional and non-institutional ecological data conservation over the long term. Interruptions to custodianship, old media, lost knowledge and the continuous evolution of species names makes resurrection of old data challenging. We caution against technological arrogance and emphasise the importance of international standards. We use a case study of a compiled set of continent-wide vegetation survey data for which, although the analyses had been published, the raw data had not. In the original study, publications containing plot data collected from the 1880s onwards had been collected, interpreted, digitised and integrated for the classification of vegetation and analysis of its conservation status across Australia. These compiled data are an extremely valuable national collection that demanded publishing in open, readily accessible online repositories, such as the Terrestrial Ecosystem Research Network (http://www.tern.org.au) and the Atlas of Living Australia (ALA: http://www.ala.org.au), the Australian node of the Global Biodiversity Information Facility (GBIF: http://www.gbif.org). It is hoped that the lessons learnt from this project may trigger a sober review of the value of endangered data, the cost of retrieval and the importance of suitable and timely archiving through the vicissitudes of technological change, so the initial unique collection investment enables multiple re-use in perpetuity.

5.
PLoS One ; 12(12): e0189288, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29281658

RESUMO

The value of sharing scientific research data is widely appreciated, but factors that hinder or prompt the reuse of data remain poorly understood. Using the Theory of Reasoned Action, we test the relationship between the beliefs and attitudes of scientists towards data reuse, and their self-reported data reuse behaviour. To do so, we used existing responses to selected questions from a worldwide survey of scientists developed and administered by the DataONE Usability and Assessment Working Group (thus practicing data reuse ourselves). Results show that the perceived efficacy and efficiency of data reuse are strong predictors of reuse behaviour, and that the perceived importance of data reuse corresponds to greater reuse. Expressed lack of trust in existing data and perceived norms against data reuse were not found to be major impediments for reuse contrary to our expectations. We found that reported use of models and remotely-sensed data was associated with greater reuse. The results suggest that data reuse would be encouraged and normalized by demonstration of its value. We offer some theoretical and practical suggestions that could help to legitimize investment and policies in favor of data sharing.


Assuntos
Atitude , Disseminação de Informação , Ciência , Humanos , Modelos Psicológicos , Recursos Humanos
6.
Sci Total Environ ; 534: 14-30, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26170116

RESUMO

To properly manage our natural and managed landscapes, and to restore or repair degraded areas, it is important to know the changes that have taken place over time, particularly with respect to land use and its cumulative effect on ecological function. In common with many places in the world, where the industrial revolution resulted in profound changes to land use and management, Australia's landscapes have been transformed in the last 200 years. Initially the VAST (Vegetation Assets, States and Transitions) system was developed to describe and map changes in vegetation over time through a series of condition states or classes; here we describe an enhancement to the VAST method which will enable identification of the factors contributing to those changes in state as a result of changes in management practice. The 'VAST-2' system provides a structure in which to compile, interpret and sequence a range of data about past management practices, their effect on site and vegetation condition. Alongside a systematic chronology of land use and management, a hierarchy of indices is used to build a picture of the condition of the vegetation through time: 22 indicators within ten criteria representing three components of vegetation condition-regenerative capacity, vegetation structure and species composition-are scored using information from a variety of sources. These indicators are assessed relative to a pre-European reference state, either actual or synthetic. Each component is weighted proportionally to its contribution to the whole, determined through expert opinion. These weighted condition components are used to produce an aggregated transformation score for the vegetation. The application of this system to a range of sites selected across Australia's tropical, sub-tropical and temperate bioregions is presented, illustrating the utility of the system. Notably, the method accommodates a range of different types of information to be aggregated.

7.
Sci Total Environ ; 526: 136-52, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25931023

RESUMO

To properly manage our natural and managed landscapes, and to restore or repair degraded areas, it is important to know the changes that have taken place over time, particularly with respect to land use and its cumulative effect on ecological function. In common with many places in the world, where the industrial revolution resulted in profound changes to land use and management, Australia's landscapes have been transformed in the last 200 years. Initially the VAST (Vegetation Assets, States and Transitions) system was developed to describe and map changes in vegetation over time through a series of condition states or classes; here we describe an enhancement to the VAST method which will enable identification of the factors contributing to those changes in state as a result of changes in management practice. The 'VAST-2' system provides a structure in which to compile, interpret and sequence a range of data about past management practices, their effect on site and vegetation condition. Alongside a systematic chronology of land use and management, a hierarchy of indices is used to build a picture of the condition of the vegetation through time: 22 indicators within ten criteria representing three components of vegetation condition-regenerative capacity, vegetation structure and species composition-are scored using information from a variety of sources. These indicators are assessed relative to a pre-European reference state, either actual or synthetic. Each component is weighted proportionally to its contribution to the whole, determined through expert opinion. These weighted condition components are used to produce an aggregated transformation score for the vegetation. The application of this system to a range of sites selected across Australia's tropical, sub-tropical and temperate bioregions is presented, illustrating the utility of the system. Notably, the method accommodates a range of different types of information to be aggregated.

8.
Sci Total Environ ; 534: 159-72, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25957788

RESUMO

We examine the DataONE (Data Observation Network for Earth) project, a transdisciplinary organization tasked with creating a cyberinfrastructure platform to ensure preservation of and access to environmental science and biological science data. Its objective was a difficult one to achieve, requiring innovative solutions. The DataONE project used a working group structure to organize its members. We use organizational discontinuity theory as our lens to understand the factors associated with success in such projects. Based on quantitative and qualitative data collected from DataONE members, we offer recommendations for the use of working groups in transdisciplinary synthesis. Recommendations include welcome diverse opinions and world views, establish shared communication practices, schedule periodic synchronous face-to-face meetings, and ensure the active participation of bridge builders or knowledge brokers such as librarians who know how to ask questions about disciplines not their own.


Assuntos
Ecologia , Monitoramento Ambiental , Comunicação , Comportamento Cooperativo , Comunicação Interdisciplinar , Percepção
9.
Sci Total Environ ; 534: 65-78, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25864797

RESUMO

Intensification of the use of natural resources is a world-wide trend driven by the increasing demand for water, food, fibre, minerals and energy. These demands are the result of a rising world population, increasing wealth and greater global focus on economic growth. Land use intensification, together with climate change, is also driving intensification of the global hydrological cycle. Both processes will have major socio-economic and ecological implications for global water availability. In this paper we focus on the implications of land use intensification for the conservation and management of freshwater ecosystems using Australia as an example. We consider this in the light of intensification of the hydrologic cycle due to climate change, and associated hydrological scenarios that include the occurrence of more intense hydrological events (extreme storms, larger floods and longer droughts). We highlight the importance of managing water quality, the value of providing environmental flows within a watershed framework and the critical role that innovative science and adaptive management must play in developing proactive and robust responses to intensification. We also suggest research priorities to support improved systemic governance, including adaptation planning and management to maximise freshwater biodiversity outcomes while supporting the socio-economic objectives driving land use intensification. Further research priorities include: i) determining the relative contributions of surface water and groundwater in supporting freshwater ecosystems; ii) identifying and protecting freshwater biodiversity hotspots and refugia; iii) improving our capacity to model hydro-ecological relationships and predict ecological outcomes from land use intensification and climate change; iv) developing an understanding of long term ecosystem behaviour; and v) exploring systemic approaches to enhancing governance systems, including planning and management systems affecting freshwater outcomes. A major policy challenge will be the integration of land and water management, which increasingly are being considered within different policy frameworks.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Água Doce/análise , Abastecimento de Água/estatística & dados numéricos , Austrália , Biodiversidade , Mudança Climática , Secas , Água Subterrânea , Hidrologia
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