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1.
Ecol Evol ; 7(1): 145-188, 2017 01.
Article in English | MEDLINE | ID: mdl-28070282

ABSTRACT

The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

2.
Ecol Evol ; 4(24): 4701-35, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25558364

ABSTRACT

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - http://www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.

3.
Rev. biol. trop ; 57(supl.1): 83-92, nov. 2009. graf, tab
Article in Spanish | LILACS, SaludCR | ID: lil-637925

ABSTRACT

Palm (Arecaceae) diversity and distribution in three humid forest fragments in Costa Rica. To determine the existing differences between species composition of palms in forest fragments with different disturbance regimes, three forest fragments at "El Zota", Cariari de Guápiles, Costa Rica, were chosen according to their disturbance level: 1) Disturbed primary forest (B1-i), 2) Secondary forest (B2) and 3) Primary forest (B1). A field survey was carried out in nested plots, where palms were identified and counted according to three size categories: i) 0.15 m to 1.35 m ii) 1.35 m to 5 m and iii) more than 5 m in height. The diversity found in B1 and B1-i is very similar, meanwhile the B2 has the lowest diversity. Palm abundance and distribution were influenced by the level of disturbance of the fragment. The B1-i presents the higher diversity in the first size categories, while B1 has the highest abundance of palms over 5 m tall. Rev. Biol. Trop. 57 (Suppl. 1): 83-92. Epub 2009 November 30.


Para determinar las diferencias existentes entre la composición de especies de palmas en fragmentos de bosque con diversos grados de alteración, se escogieron tres fragmentos en "El Zota", Costa Rica, según el grado de alteración: 1) Bosque primario alterado (B1-i), 2) Bosque secundario (B2) y 3) Bosque primario (B1). Se hizo un muestreo con parcelas anidadas donde se identificaron y contabilizaron las palmas según tres categorías de tamaño: i) 0.15 m a 1.35 m, ii) 1.35 m a 5 m y iii) más de 5 m de alto. Se observó que la diversidad de B1 y B1-i es muy similar, mientras que B2 posee la menor diversidad. La abundancia y distribución de las palmas estaba influenciada por el nivel de alteración del fragmento. El B1-i presenta una mayor diversidad de la primera categoría de tamaño, mientras que B1 tiene mayor abundancia de palmas sobre 5 m de alto.


Subject(s)
Areca , Regeneration , Arecaceae/classification , Rainforest , Costa Rica
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