The number of native plants and vertebrates currently protected in each mediterranean region and those gained under a scenario whereby 25% of potential lands advance biodiversity conservation.

<p>We used species-area curves developed for each taxa; ‘z’ exponents were as follows: birds 0.125; mammals 0.315, amphibians 0.148, reptiles 0.293, and plants 0.129.</p

Proportional extent of land cover categories in each of the world's five mediterranean regions: protected (IUCN categories I-VI), converted (to urban), impacted (by intensive agriculture), and lands with conservation potential.

<p>Proportional extent of land cover categories in each of the world's five mediterranean regions: protected (IUCN categories I-VI), converted (to urban), impacted (by intensive agriculture), and lands with conservation potential.</p

Comparison of species area curves for (a) the Mediterranean Basin; (b) South Africa, Australia, the Californias and Chile, based on the number of total plant and vertebrate species.

<p>The species currently protected (IUCN categories I-VI) are indicated (approximately) by a circle and the area that is converted or impacted is represented by a square. The potential lands are represented by the space in between these two points. The increase in species protected under a conservation scenario whereby 25% of natural and semi-natural landscapes in each region are managed for biodiversity conservation is shown by a red circle.</p

The area (km²) and proportion of land which is protected (IUCN categories I-VI), converted, impacted, or with conservation potential (see text for description of each class).

<p>Estimates of the number of native plants are from Cowling et al. (1996) and terrestrial vertebrates from World Wildlife Fund (2006).</p

Global screening for Critical Habitat in the terrestrial realm

<div><p>Critical Habitat has become an increasingly important concept used by the finance sector and businesses to identify areas of high biodiversity value. The International Finance Corporation (IFC) defines Critical Habitat in their highly influential Performance Standard 6 (PS6), requiring projects in Critical Habitat to achieve a net gain of biodiversity. Here we present a global screening layer of Critical Habitat in the terrestrial realm, derived from global spatial datasets covering the distributions of 12 biodiversity features aligned with guidance provided by the IFC. Each biodiversity feature is categorised as ‘likely’ or ‘potential’ Critical Habitat based on: 1. Alignment between the biodiversity feature and the IFC Critical Habitat definition; and 2. Suitability of the spatial resolution for indicating a feature’s presence on the ground. Following the initial screening process, Critical Habitat must then be assessed in-situ by a qualified assessor. This analysis indicates that a total of 10% and 5% of the global terrestrial environment can be considered as likely and potential Critical Habitat, respectively, while the remaining 85% did not overlap with any of the biodiversity features assessed and was classified as ‘unknown’. Likely Critical Habitat was determined principally by the occurrence of Key Biodiversity Areas and Protected Areas. Potential Critical Habitat was predominantly characterised by data representing highly threatened and unique ecosystems such as ever-wet tropical forests and tropical dry forests. The areas we identified as likely or potential Critical Habitat are based on the best available global-scale data for the terrestrial realm that is aligned with IFC’s Critical Habitat definition. Our results can help businesses screen potential development sites at the early project stage based on a range of biodiversity features. However, the study also demonstrates several important data gaps and highlights the need to incorporate new and improved global spatial datasets as they become available.</p></div

Global screening layer for terrestrial Critical Habitat.

<p>Likely and potential Critical Habitat are depicted in purple and pink, respectively. Unknown areas are depicted in dark grey. Marine areas are depicted in blue, and were not assessed. The screening layer is developed as a raster of 1 km grid cell size.</p

Datasets incorporated into the Critical Habitat screening layer.

<p>Datasets incorporated into the Critical Habitat screening layer.</p

Screening layer classification scheme.

<p>Classification of data subsets as likely or potential Critical Habitat is based on the strength of alignment with IFC PS6 criteria and scenarios and the spatial resolution of the data (adapted from Martin et al. [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0193102#pone.0193102.ref018" target="_blank">18</a>]).</p

Surface areas of likely, potential and combined (likely/potential) Critical Habitat (CH) identified under individual criteria and scenarios.

<p>Surface areas of likely, potential and combined (likely/potential) Critical Habitat (CH) identified under individual criteria and scenarios.</p

Critical Habitat criteria and scenarios.

<p>Critical Habitat criteria and scenarios.</p