Ecological restoration is widely used to reverse the environmental degradation caused by human activities. However, the effectiveness of restoration actions in increasing provision of both biodiversity and ecosystem services has not been evaluated systematically. A meta-analysis of 89 restoration assessments in a wide range of ecosystem types across the globe indicates that ecological restoration increased provision of biodiversity and ecosystem services by 44 and 25%, respectively. However, values of both remained lower in restored versus intact reference ecosystems. Increases in biodiversity and ecosystem service measures after restoration were positively correlated. Results indicate that restoration actions focused on enhancing biodiversity should support increased provision of ecosystem services, particularly in tropical terrestrial biomes.

Aim To analyse the conservation status of tropical dry forests at the global scale, by combining a newly developed global distribution map with spatial data describing different threats, and to identify the relative exposure of different forest areas to such threats.Location Global assessment.Methods We present a new global distribution map of tropical dry forest derived from the recently developed MODIS Vegetation Continuous Fields (VCF) product, which depicts percentage tree cover at a resolution of 500 m, combined with previously defined maps of biomes. This distribution map was overlaid with spatial data to estimate the exposure of tropical dry forests to a number of different threats: climate change, habitat fragmentation, fire, human population density and conversion to cropland. The extent of tropical dry forest currently protected was estimated by overlaying the forest map with a global data set of the distribution of protected areas.

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Protected areas are one of the cornerstones for conserving the world's remaining biodiversity, most of which occurs in tropical forests. We use multiple sources of satellite data to estimate the extent of forest habitat and loss over the last 20 years within and surrounding 198 of the most highly protected areas (IUCN status 1 and 2) located throughout the world's tropical forests. In the early 1980s, surrounding habitat in the 50‐km unprotected or less highly protected “buffers” enhanced the protected areas' effective size and their capacity to conserve richness of forest‐obligate species above the hypothetical case of complete isolation. However, in nearly 70% of the surrounding buffers, the area of forest habitat declined during the last 20 years, while 25% experienced declines within their administrative boundaries. The loss of habitat occurred in all tropical regions, but protected areas in South and Southeast Asia were most severely affected because of relatively low surrounding forest habitat in the early 1980s and high subsequent loss, particularly in dry tropical forests. The future ability of protected areas to maintain current species richness depends on integrating reserve management within the land use dynamics of their larger regional settings.

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Restoration initiatives seek to address widespread deforestation and forest degradation, but face substantial problems. “Passive restoration”, whereby abandoned agricultural land undergoes secondary succession, is often slow, owing to biotic and abiotic limitations. “Active restoration”, chiefly accomplished by planting trees, can be very expensive if large areas are to be restored. We suggest “woodland islets” as an alternative way to achieve ecological restoration in extensive agricultural landscapes, particularly in low-productivity environments. This approach involves the planting of many small, dense blocks of native trees to enhance biodiversity and provide a range of ecosystem services. If the surrounding land is abandoned, the islets act as sources of woodland species and seed, which can accelerate woodland development. Alternatively, if the surrounding area is used for cultivation or pasture, the islets will increase the conservation value of the land and offer the potential for income generation. Here, we review existing approaches to woodland restoration and evaluate the relative strengths and weaknesses of the woodland islets approach.This research has been financed by the projects: EU INCO Programme (REFORLAN: EU INCO-CT-2006- 032132), UE Alpha Programme II-0411-FA-FCD-FI-FC, Spanish Ministry of Science and Education CGL2004-00355/BOS, Madrid Government S-0505/AMB/0355\ud (REMEDINAL), and UK RELU Award 227/0010 “FarmCAT”

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Variety mixtures can provide functional diversity that limits pathogen and pest expansion, and that makes use of knowledge about interactions between hosts and their pests and pathogens to direct pathogen evolution. Indeed, one of the most powerful ways both to reduce the risk of resistance break-down and to still make use of defeated resistance genes is to use cereal variety and species mixtures. The most important mechanisms reducing disease in variety and species mixtures are barrier and frequency effects, and induced resistance. Differential adaptation, i.e. adaptation within races to specific host genotypic backgrounds, may prevent the rapid evolution of complex pathotypes in mixtures. Mixtures generally stabilise yields and yield losses due to disease; abiotic stresses are also better buffered than in pure stands. When mixture components are carefully put together, product quality can be enhanced or at least equal that of the pure stands. Mixture use in practice worldwide is reviewed. functional diversity / induced resistance / differential adaptation / yield stability / evolutionary plant breedingRésumé -Les mélanges de variétés et les mélanges interspécifiques de céréales dans la pratique. Les variétés en mélanges, de par leur diversité génétique, limitent le développement des épidémies et des ravageurs. Cette diversité peut être organisée selon notre connaissance des interactions hôte -agent pathogène pour influer sur l'évolution des