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Throughout the world, forest covers one-third of the land's area. Present and historical human activities caused tremendous land use changes and triggered the onset of unseen climate changes. Yet, these socio-economically based environmental changes interfere with services that forests provide to mankind from global to local scales. Densely populated regions such as Flanders (Belgium), with over 430 people per km2, have the dubious honour to serve as examples of extreme human induced forest changes. The issue of forest biodiversity is reviewed in the light of the Millennium Ecosystem Assessment scheme. Flanders is a poorly forested region (11% forest cover); supporting services are consequently low. Merely 16% of that area has known 230 years of continuous forest cover, representing forest with the highest current biodiversity. Also, the demands for regulating services are growing and the limits may have been reached. Provisioning services may increase again in future when demands for, for example bio-energy, increase. Cultural services, particularly the recreational function, have increased greatly. Human well-being in Flanders partly depends on the services provided by forest ecosystems. However, as demands on forests are huge, a shift to a sustainable use of forest resources will be essential to assure its beneficial role for present and future generations. [ABSTRACT FROM AUTHOR]

A first comprehensive account on the dolichopodid fauna (Diptera: Dolichopodidae) of Portugal is presented as the result of multiple surveys by primarily Portuguese researchers between 2009 and 2016. All mainland Portuguese provinces and all districts but one (Évora) were investigated. A total of 761 dolichopodid samples were collected in 278 sampling sites distributed over 87 municipalities and 182 localities, with nearly ¾ of the samples gathered by sweep net. They contained 6,680 specimens of 200 different species, with 142 recognized (known), 40 new (undescribed) and 18 doubtful species. Medetera and Dolichopus were the most diverse among the recognized species, with 20 and 18 species respectively. Fourteen genera were represented by the new species, with Medetera as most diverse. The doubtful species included one species of Pelastoneurus, which is a first record of this genus for the Palaearctic realm. At present 208 dolichopodid species are known from Portugal. A checklist with 150 recognized species is presented, with first records of 116 species for Portugal. For nearly every species, information on its distribution, ecology and rarity in Portugal and northwestern Europe is given, as well as its seasonal activity in Portugal. Raw distribution data are available as dataset in GBIF. Seventy-five pictures of species in the field, and 15 habitat photos are also provided. Current data suggest that a higher proportion of Portuguese species are rare as compared to the Flemish fauna (northern Belgium). Both share 104 species, with 38 species only recorded from Portugal; only seven can be considered Iberian or Portuguese specialities. Though differences between the two Portuguese biomes cannot be substantiated at this moment, two very common and widespread European species, Campsicnemus scambus and Chrysotimus molliculus, seem to be restricted to the Eurosiberian biome in the northwest of the country. In terms of generic representation, the Portuguese dolichopodid fauna occupies an intermediate position between those of northwestern European and other Mediterranean countries. Despite the large amount of data gathered, the dolichopodid fauna of Portugal remains insufficiently known and a considerable number of additional known and new species can be expected with continued sampling.

Following habitat fragmentation individual habitat patches may lose species over time as they pay off their "extinction debt." Species with relatively low rates of population extinction and colonization ("slow" species) may maintain extinction debts for particularly prolonged periods, but few data are available to test this prediction. We analyzed two unusually detailed data sets on forest plant distributions and land-use history from Lincolnshire, United Kingdom, and Vlaams-Brabant, Belgium, to test for an extinction debt in relation to species-specific extinction and colonization rates. Logistic regression models predicting the presence-absence of 36 plant species were first parameterized using data from Lincolnshire, where forest cover has been relatively low (approximately 5-8%) for the past 1000 years. Consistent with extinction debt theory, for relatively slow species (but not fast species) these models systematically underpredicted levels of patch occupancy in Vlaams-Brabant, where forest cover was reduced from approximately 25% to <10% between 1775 and 1900 (it is presently 6.5%). As a consequence, the ability of the Lincolnshire models to predict patch occupancy in Vlaams-Brabant was worse for slow than for fast species. Thus, more than a century after forest fragmentation reached its current level an extinction debt persists for species with low rates of population turnover.