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International audience; About one-third of the world’s land surface is used for farming, a fact that bears important implications for biodiversity. In Europe, for instance, an estimated 50 percent of all wild species are reliant on agricultural habitats, while agricultural productivity often depends on the presence or absence of particular species. Despite this close coupling, surprisingly little is known about the status and evolution of farmland biodiversity. A team of European and African researchers, hoping to fill this gap in information, recently invented and piloted a new toolbox called the BioBio indicator set, which measures 23 different instances of biodiversity across a variety of farm types and scales in Europe. Applications were also tested in Tunisia, Ukraine, and Uganda, where they proved a feasible starting point for adaptation to the agricultural context of different countries.

The analysis of the dependence of landscape patterns on environment was carried out in order to investigate the landscape structure evolution of Spain. The underlying concept was that the dependence between landscape spatial structure and environmental factors could be gradually decreasing over time. Land cover data were recorded from aerial photo interpretation of 206 4 × 4 km2 samples from three different years: 1956, 1984 and 1998. Geographical variables were taken into consideration together with the purely environmental ones. General Linear Models of repeated measures were then used to segregate environmental from geographical effects on the pattern of the land cover patches of the samples. Aridity, lithology and topography were the environmental factors used to analyse structural indices of landscape. Landscape composition has a higher dependence on environment than configuration. Environmental variables showed higher correlations with landscape composition and configuration than geographical variables. Among them, overall the climatic aridity and topography significantly accounted for more variation than did lithology. There was a high degree of stability in land cover composition over time, with some significant exceptions. Nevertheless, the registered increase of fragmentation over time has demonstrated that configuration measures are needed to fully assess landscape change., Se ha analizado la evolución de la estructura del paisaje español mediante un análisis de la dependencia de los patrones del paisaje respecto del medioambiente. La hipótesis principal es que la dependencia entre la estructura del paisaje y los factores ambientales está disminuyendo con el tiempo. Los datos de composición y configuración de paisaje fueron tomados mediante interpretación de fotografías aéreas tomadas en los años 1956, 1984 y 1998 en 206 parcelas de 4 × 4 km2. Se han tenido en cuenta variables geográficas junto con las variables puramente ambientales. Se han utilizado modelos lineales generalizados de medidas repetidas para determinar la importancia de los efectos ambientales con respecto a los geográficos en los patrones de paisaje. Las variables ambientales utilizadas para analizar los índices estructurales del paisaje fueron: aridez, litología y topografía. Existe una mayor dependencia ambiental en la composición que en la configuración. Las variables ambientales tuvieron un mayor efecto sobre la estructura del paisaje que las geográficas. Entre aquellas, la aridez climática y la topografía influyeron más que la litología. La composición se mostró en general estable a lo largo del periodo de estudio con algunas excepciones. Sin embargo, se observó una fragmentación significativa que indica la necesidad de analizar los índices de configuración para detectar los cambios de paisaje.

Increased adoption of silvoarable agroforestry (SAF) systems in Europe, by integrating trees and arable crops on the same land, could offer a range of environmental benefits compared with conventional agricultural systems. Soil erosion, nitrogen leaching, carbon sequestration and landscape biodiversity were chosen as indicators to assess a stratified random sample of 19 landscape test sites in the Mediterranean and Atlantic regions of Europe. At each site, the effect of introducing agroforestry was examined at plot-scale by simulating the growth of one of five tree species (hybrid walnut Juglans spp., wild cherry Prunus avium L., poplar Populus spp., holm oak Quercus ilex L. subsp. ilex and stone pine Pinus pinea L.) at two tree densities (50 and 113 trees ha 1) in combination with up to five crops (wheat Triticum spp., sunflower Helianthus annuus L., oilseed rape Brassica napus L., grain maize and silage maize Zea mays L.). At landscape-scale, the effect of introducing agroforestry on 10 or 50% of the agricultural area, on either the best or worst quality land, was examined. Across the 19 landscape test sites, SAF had a positive impact on the four indicators with the strongest effects when introduced on the best quality land. The computer simulations showed that SAF could significantly reduce erosion by up to 65% when combined with contouring practices at medium (>0.5 and 3 t ha 1 a 1) erosion sites. Nitrogen leaching could be reduced by up to 28% in areas where leaching is currently estimated high (>100 kg N h 1 a 1), but this was dependent on tree density.With agroforestry, predicted mean carbon sequestration through immobilization in trees, over a 60-year period, ranged from 0.1 to 3.0 t C h 1 a 1 (5–179 t C h 1) depending on tree species and location. Landscape biodiversity was increased by introducing SAF by an average factor of 2.6. The implications of this potential for environmental benefits at European-scale are discussed.

There is a well defined policy requirement for a practical and reproducible procedure for surveillance and monitoring of habitats in Spain that can subsequently be fitted into a European framework. Any such procedure also needs to incorporate records of the Spanish habitat classification. A procedure is described that will satisfy those requirements and has been field tested both in Spain and in Europe. Rigorous rules and training are required; otherwise changes from baseline records cannot reliably be separated from background noise. The procedure uses the classical plant life forms long used in biogeography and is based on their statistical relationship with the environment. This relationship has been validated statistically and the procedure has also been tested in the field in all European environmental zones and widely in Spain. 130 General Habitat Categories are defined and these are enhanced in the field by recording environmental, site and management qualities to produce a flexible database that can then be interrogated. The rules for mapping the habitats mean that they can be used for descriptive purposes or for monitoring. In conjunction with stratification and subsequent sampling, national estimates of stock and change can then be produced. Finally, based on the previous experience of SISPARES, a methodological scheme is proposed for adapting the approach to Spain. The proposal will allow links to be made between European scale surveillance and monitoring to those already obtained for Spain., en España políticas bien definidas que demandan procedimientos prácticos y reproducibles para llevar a cabo la supervisión y seguimiento de los hábitats, de modo que subsecuentemente puedan ajustarse al marco Europeo. Cualquier procedimiento de estas características necesita poder incorporar datos registrados de la clasificación española de hábitats. Aquí se describe un procedimiento que satisface dichos requisitos y que ha sido probado tanto en España como en el resto de Europa. El método exige reglas rigurosas y entrenamiento de campo; si no los cambios en los registros básicos no se podrán separar de manera fiable de los errores subjetivos cometidos durante la toma de datos. El procedimiento utiliza las clásicas formas de vida, ampliamente utilizadas en estudios biogeográficos y está basado en sus relaciones con el medio ambiente. Esta relación ha sido validada estadísticamente y el procedimiento ha sido probado en el campo en todas las zonas ambientales de Europa. En España, se han definido 130 Categorías Generales de Hábitats y se han verificado en el campo mediante el registro de atributos ambientales, estacionales y de manejo, de forma que puedan ser incluidas en una base de datos suficientemente flexible. Las directrices para la cartografía de hábitats posibilitan su uso descriptivo y permiten su seguimiento. Al mismo tiempo, con la estratificación y subsecuente muestreo, es posible hacer estimaciones nacionales de existencias y de cambios Finalmente, basados en las experiencias previas de SISPARES, se propone un esquema metodológico para adaptar BIOHAB a España. La propuesta permitirá conectar los resultados a escala Europea de supervisión y seguimiento con los obtenidos a escala española.

International audience; Les haies ont des origines complexes, comme le montrent la diversité de leurs rôles et l'étymologie du mot. Nous discutons de ces deux points dans l'article, ainsi que de la question de la définition de la haie pour une cartographie visant à définir les ressources régionales. Du point de vue de l'écologie du paysage, les haies sont une combinaison d'éléments sociaux, découlant des pratiques de gestion, et de caractéristiques naturelles et structurales. La complexité de la structure végétale et des fonctions des haies rend une classification difficile. Des paramètres botaniques, faunistiques, structural, physiques ou relevant de l'écologie des paysages doivent être considéré pour conduire une classification robuste et utile. La discussion des mérites relatifs de chacune de ces caractéristiques nous amène à conclure qu'une classification unique n'est pas appropriée. Différentes typologies doivent être établies de façon à satisfaire la diversité des objectifs des niveaux locaux aux niveaux nationaux. Certaines classifications existantes peuvent être utilisées dans quelques cas ; autrement de nouvelles typologies doivent être développées.

In a large ecological survey of Britain,13841 quadrats were sampled in 508 1-km squares. The quadrats included 1132 species of vascular plants, of which 643 occurred in 10 or more quadrats. Applying the method of Gaussian logistic regression to data from this survey, ecological optima and tolerances of species were estimated for Ellenberg’s seven ecological indicator variables. Tolerances showed very little relation to the original scales. Most optima were within the range of the original scales but a few species lacked optima for some variables. Optima showed a strong positive relation to original values, but the resulting scale was compressed. We propose a locally-weighted trend line to convert each optimum value to an estimate of the original value. Reprediction using methods based on large-scale quadrat samples offers a very good means of extending Ellenberg’s values to a new geographic area such as Britain.