Search results for " Land"
showing 10 items of 3130 documents
Disentangling the latitudinal and altitudinal shifts in community composition induced by climate change: The case of riparian birds
2021
11 pages; International audience; Aim: This study investigates whether, and how, the composition of riparian bird communities has been affected by climate warming and habitat change. Although these two forces act separately, their respective contributions are rarely examined. Moreover, while the response of a given community may be a function of latitude and altitude, most studies have focused on these gradients separately. Riparian ecosystems are an opportunity to investigate community change along latitudinal and elevational gradients.Location: France, three major rivers (the Doubs, the Allier and the Loire)Taxon: Birds.Methods: Drawing upon bird community monitoring data over a period of…
Woodland key habitats in preserving polypore diversity in boreal forests: Effects of patch size, stand structure and microclimate
2016
Abstract Woodland key-habitats (WKHs) are set-asides in managed forests that are conceived to maintain specific aspects of forest biodiversity and they are widely used in Northern European countries. WKHs are often quite small (from 0.1 to a few hectares) and thus it is unclear if they can maintain biodiversity. We studied the effects of WKH size, microclimate and forest structure on species richness and composition of polypores, a group of wood-decaying fungi that has become threatened due to clear-cut forestry. The WKHs studied varied in size between 0.05 and 3.6 ha, and the control forests from 6.5 to 44.7 ha. Patch size and the volumes of logs and standing dead trees significantly affec…
Do small protected habitat patches within boreal production forests provide value for biodiversity conservation? : A systematic review protocol
2019
Background Forest harvesting is the main driver of habitat degradation and biodiversity loss in forests of the boreal zone. To mitigate harmful effects, small-scale habitats with high biodiversity values have been protected within production forests. These include woodland key habitats, and other small-scale habitat patches protected by voluntary conservation action. This article describes a protocol for a systematic review to synthesize the value of small habitat patches left within production landscapes for biodiversity. The topic for this systematic review arose from a discussion with the Finnish forestry sector and was further defined in a stakeholder workshop. Research question: Do sma…
Tropical Andean forests are highly susceptible to nutrient inputs--rapid effects of experimental N and P addition to an Ecuadorian montane forest.
2012
Tropical regions are facing increasing atmospheric inputs of nutrients, which will have unknown consequences for the structure and functioning of these systems. Here, we show that Neotropical montane rainforests respond rapidly to moderate additions of N (50 kg ha -1 yr -1) and P (10 kg ha -1 yr -1). Monitoring of nutrient fluxes demonstrated that the majority of added nutrients remained in the system, in either soil or vegetation. N and P additions led to not only an increase in foliar N and P concentrations, but also altered soil microbial biomass, standing fine root biomass, stem growth, and litterfall. The different effects suggest that trees are primarily limited by P, whereas some pro…
Forest multifunctionality is not resilient to intensive forestry
2021
AbstractThere is ample evidence that intensive management of ecosystems causes declines in biodiversity as well as in multiple ecosystem services, i.e., in multifunctionality. However, less is known about the permanence and reversibility of these responses. To gain insight into whether multifunctionality can be sustained under intensive management, we developed a framework building on the concept of resilience: a system’s ability to avoid displacement and to return or transform to a desired state. We applied it to test the ability of forest multifunctionality to persist during and recover from intensive management for timber production in a boreal forest. Using forest growth simulations and…
Changes in evapotranspiration and phenology as consequences of shrub removal in dry forests of central Argentina
2014
More than half of the dry woodlands (forests and shrublands) of the world are in South America, mainly in Brazil and Argentina, where in the last years intense land use changes have occurred. This study evaluated how the transition from woody-dominated to grass-dominated system affected key ecohydrological variables and biophysical processes over 20 000 ha of dry forest in central Argentina. We used a simplified surface energy balance model together with moderate-resolution imaging spectroradiometer–normalized difference vegetation index data to analyse changes in above primary productivity, phenology, actual evapotranspiration, albedo and land surface temperature for four complete growing …
Effect of simulated faunal impoverishment and mixture on the ecological structure of modern mammal faunas: Implications for the reconstruction of Mio…
2011
15 pages; International audience; The strong link between environment and the ecological diversity of communities is often used for drawing palaeoenvironmental inferences from fossil assemblages. Here we focus on the reliability of fossil samples in comparison to original communities when inferring palaeoenvironments from the ecological diversity of fossil mammal faunas. Taphonomic processes and sampling techniques generally introduce two kinds of biases in fossil samples: 1) the directional impoverishment of communities, i.e. the absence of some specific categories of bones, individuals or species; and 2) the mixture of several communities, temporally (timeaveraging) and/or spatially (spac…
Late Quaternary changes in bat palaeobiodiversity and palaeobiogeography under climatic and anthropogenic pressure: new insights from Marie-Galante, …
2016
25 pages; International audience; Data on Lesser Antillean Late Quaternary fossil bat assemblages remains limited, leading to their general exclusion from studies focusing on Caribbean bat palaeobiodiversity and palaeobiogeography. Additionally, the role of climatic versus human pressure driving changes in faunal communities remains poorly understood. Here we describe a fossil bat assemblage from Blanchard Cave on Marie-Galante in the Lesser Antilles, which produced numerous bat remains from a well-dated, stratified context. Our study reveals the occurrence of at least 12 bat species during the Late Pleistocene and Early Holocene on Marie-Galante, whereas only eight species are currently kn…
Comparing pollen spectra from modified Tauber traps and moss samples: examples from a selection of woodlands across Europe
2010
This paper compares pollen spectra derived from modified Tauber traps and moss samples from a selection of woodland types from Bulgaria, the Czech Republic, Georgia, Greece, Poland, Switzerland and Wales. The study examines the representation of individual taxa in the two sampling media and aims to ascertain the duration of pollen deposition captured by a moss. The latter aim was pursued through the calculation of dissimilarity indexes to assess how many years of pollen deposited in a pollen trap yield percentage values that are most similar to those obtained from the moss. The results are broadly scattered; the majority of moss samples being most similar to several years of pollen depositi…
Biodiversity is not (and never has been) a bed of roses!
2011
9 pages; International audience; Over the last decades, the critical study of fossil diversity has led to significant advances in the knowledge of global macroevolutionary patterns of biodiversity. The deep-time history of life on Earth results from background originations and extinctions defining a steady-state, nonstationary equilibrium occasionally perturbed by biotic crises and "explosive" diversifications. More recently, a macroecological approach to the large-scale distribution of extant biodiversity offered new, stimulating perspectives on old theoretical questions and current practical problems in conservation biology. However, time and space are practically distinct, but functional…