Conti G.,National University of Cordoba |
Kowaljow E.,National University of Cordoba |
Baptist F.,Biotope |
Rumpel C.,French National Institute for Agricultural Research |
And 3 more authors.
Plant and Soil | Year: 2016
Background and aims: Subtropical seasonally dry forests from South America are now experiencing one of the highest rates of forest-cover change globally. These changes may affect the dynamics of soil organic carbon (SOC) including long-term stabilization processes, with profound consequences for the fertility and carbon storage of these ecosystems. Methods: In order to explore the effect of different land-use regimes on SOC dynamics, we determined the amount and quality of plant litter, the amount and quality (lignin and carbohydrate content) of SOC, and the soil basal respiration rates across seasonally dry Chaco forests of Argentina. Results: Changes in land-use regimes significantly reduced the amount of litter but not its quality. As a consequence, the SOC content was also reduced together with SOC quality. Unexpectedly, we found a higher CO2 release per SOC unit in soils with lower amount and quality of SOC. Conclusions: The results presented here show a clear effect of different land-use regimes on SOC dynamics through a reduction in the amount and quality of SOC. Additionally, we found that potential microbial activity is somehow disconnected from substrate quantity and quality, suggesting that the molecular structure of SOC is not significantly affecting long-term soil stabilization processes across these seasonally-dry ecosystems. © 2016, Springer International Publishing Switzerland.
Penone C.,CNRS Science Conservation Center |
Le Viol I.,CNRS Science Conservation Center |
Pellissier V.,CNRS Science Conservation Center |
Julien J.-F.,CNRS Science Conservation Center |
And 2 more authors.
Conservation Biology | Year: 2013
Biodiversity monitoring at large spatial and temporal scales is greatly needed in the context of global changes. Although insects are a species-rich group and are important for ecosystem functioning, they have been largely neglected in conservation studies and policies, mainly due to technical and methodological constraints. Sound detection, a nondestructive method, is easily applied within a citizen-science framework and could be an interesting solution for insect monitoring. However, it has not yet been tested at a large scale. We assessed the value of a citizen-science program in which Orthoptera species (Tettigoniidae) were monitored acoustically along roads. We used Bayesian model-averaging analyses to test whether we could detect widely known patterns of anthropogenic effects on insects, such as the negative effects of urbanization or intensive agriculture on Orthoptera populations and communities. We also examined site-abundance correlations between years and estimated the biases in species detection to evaluate and improve the protocol. Urbanization and intensive agricultural landscapes negatively affected Orthoptera species richness, diversity, and abundance. This finding is consistent with results of previous studies of Orthoptera, vertebrates, carabids, and butterflies. The average mass of communities decreased as urbanization increased. The dispersal ability of communities increased as the percentage of agricultural land and, to a lesser extent, urban area increased. Despite changes in abundances over time, we found significant correlations between yearly abundances. We identified biases linked to the protocol (e.g., car speed or temperature) that can be accounted for ease in analyses. We argue that acoustic monitoring of Orthoptera along roads offers several advantages for assessing Orthoptera biodiversity at large spatial and temporal extents, particularly in a citizen science framework. © 2013 Society for Conservation Biology.
Viard-Cretat F.,IRSTEA |
Viard-Cretat F.,CNRS Alpine Ecology Laboratory |
Viard-Cretat F.,Joseph Fourier University |
Baptist F.,BIOTOPE |
And 3 more authors.
Plant Ecology | Year: 2013
Allelopathy is recognized as an important process in plant-plant interactions, but how it affects plant communities growing in competitive conditions has not been assessed. This article investigates whether the allelopathic effect of Festuca paniculata is modified by competition between target plants in subalpine grasslands. We hypothesized that plants growing in mixed stands will be more affected by allelochemicals than the same species in monoculture. At Lautaret pass (Northern French Alps), a pot experiment was designed. We used leachates from donor pots (Treatments: 1. Bare soil, 2. F. paniculata clipped, and 3. F. paniculata unclipped) to water target pots (Treatments: 1. Control (soil only), 2. Dactylis glomerata, 3. Agrostis capillaris, and 4. D. glomerata and A. capillaris). Target plants were cultivated during one growing season. The effects of leachates from donor pots and interspecific competition in target pots were evaluated by measuring the final biomass of plants. Soil fertility was controlled in all target pots by measuring NO3 -, NH4 +, N, and C % of the soil. Effect of target treatment under: Both D. glomerata and A. capillaris grew better in monocultures than in mixture. Effect of donor treatment on monocultures: Under bare soil, D. glomerata grew better than under F. paniculata leachates. By contrast, A. capillaris did not respond to donor pot treatment. Effect of donor treatment on mixtures: However, when both species were cultivated together under F. paniculata leachates, the biomass of D. glomerata was similar to that in monoculture under bare soil. Differences in sensitivity to allelopathy reversed the impact of interspecific competition: A. capillaris facilitated D. glomerata under allelopathy, which made allelopathy of F. paniculata on D. glomerata inefficient. The complexity of overlapping mechanisms of plant-plant interactions are highlighted by this semi-natural experiment. In subalpine grasslands, allelopathy not only limits the growth of neighboring plants, but it may also modify community assembly by affecting other plant-plant interactions such as competition. This study contributes to explore the way allelopathy interacts with other plant-plant interactions in natural systems. © 2012 Springer Science+Business Media Dordrecht.
Fouquet A.,CNRS Guyane USR3456 |
Pineau K.,Biotope |
Rodrigues M.T.,University of Sao Paulo |
Mailles J.,Direction de lEnvironnement de lAmenagement et du Logement de la Martinique |
And 3 more authors.
Systematics and Biodiversity | Year: 2013
Amphibian faunas of the Lesser Antilles are depauperate, with only a few species being endemic and generally threatened. Allobates chalcopis from the island of Martinique is a particularly enigmatic case being the only known dendrobatid endemic to an oceanic island. This species has previously been suggested as being introduced to Martinique. The question of its true origin remained unresolved because no individuals were found since its formal description in the 1990s. Twenty years after the last observation of the species, we succeeded in finding an isolated population of Allobates chalcopis in Martinique. The rediscovery allowed us to investigate the species' phylogenetic position, confirming that it is nested within a clade of lowland Amazonian Allobates but nonetheless distantly related to any known species of the group. The arrival of the species in Martinique likely corresponds to an overseas dispersal from South America during the late Miocene, as previously hypothesized for Bothrops lanceolatus and Leptodactylus fallax; two other species endemic to Martinique and surrounding islands. However, the species was not found in its type locality 500 m a.s.l. but 300 m higher in altitude, in herbaceous areas of the summit of Montagne Pelée. The possible range reduction and population decline in combination with the evidence of endemicity of the species highlights the need for a reassignment of the current Red List status. Furthermore, a refined conservation strategy is needed to guarantee the long-term viability of Allobates chalcopis in its native range. © 2013 The Natural History Museum.
van Teeffelen A.J.A.,VU University Amsterdam |
van Teeffelen A.J.A.,Wageningen University |
Opdam P.,Wageningen University |
Watzold F.,TU Brandenburg |
And 8 more authors.
Landscape and Urban Planning | Year: 2014
Protected areas are a cornerstone of current biodiversity policy. The continued loss of biodiversity, however, as well as the limited scope to extend protected area networks necessitates a conservation perspective that encompasses both protected areas and the wider landscape. This calls for policy instruments that can govern land use dynamics, simultaneously meeting demands for conservation (i.e. no net loss of biodiversity) and economic development. Conservation banking could be such an instrument, but only when certain criteria are met. Building on the theory of ecological networks, we combine ecological, economic and institutional perspectives on conservation banking to identify when and where conservation banking could be feasible. Economic prerequisites include sufficient market activity to match demand and supply. Adequate regulatory capacity is needed to design and enforce trading rules. From an ecological perspective, habitat turnover is least detrimental in large and well-connected networks. For many ecosystem types, those prerequisites will be rarely met in practice: sufficient market activity implies sufficient habitat turnover, but most ecological networks are not robust enough to buffer frequent habitat turnover. Therefore, banking is best limited to common and fast-regenerating ecosystem types (e.g. certain coastal systems, wetlands, nutrient-rich grasslands). Furthermore, conservation banking could be applied to a subset of the network only, i.e. the wider landscape, as a complementary instrument to protected area policy. With appropriate trading rules and institutional arrangements, the loss and gain of habitat could be governed to improve the spatial cohesion and size of ecological networks and the capacity of landscapes to support biodiversity. © 2014 Elsevier B.V.
Quetier F.,Biotope |
Quetier F.,CNRS Alpine Ecology Laboratory |
Regnery B.,French Natural History Museum |
Levrel H.,French Research Institute for Exploitation of the Sea
Environmental Science and Policy | Year: 2014
French regulations concerning the mitigation of development impacts have been progressively strengthened with offsets now required for impacts on forests, wetlands, and protected species, among others. In 2012, following a national consultative process called Grenelle de l'Environnement, legal requirements in terms of monitoring and effective implementation of measures aimed at avoiding, reducing and offsetting impacts were strengthened. This has created strong "demand" for offsets.The workability of these new requirements has come under scrutiny, not least because of their strong legal and financial implications for developers. In this context, official government guidance on implementing the mitigation hierarchy was published in 2012. Under this guidance, the aim of the mitigation hierarchy is to achieve no net loss (NNL) of biodiversity, and preferably a net gain for currently threatened biodiversity and ecosystems. We discuss what NNL means in this context, and highlight some of the technical and governance issues raised by the French approach to NNL.Our analysis shows that the French guidance, in spite of its laudable ambition, does not address the institutional arrangements and science base needed to reach the policy's objective of NNL. The burden of designing and building adequate institutional arrangements is shifted down to local and regional permitting authorities, and even developers themselves. Consequently, and in spite of the increasing demand for offsets, the result is a highly variable and often ineffective project by project approach to offset supply, with minimal commitments. Unless the institutional and scientific challenges are tackled, the likely outcome will be an expansion of "paper offsets". © 2013 Elsevier Ltd.
Veron G.,CNRS Systematics, Biodiversity and Evolution Institute |
Patou M.-L.,Biotope |
Jennings A.P.,SMALL CARNIVORES Research and Conservation
Mammalian Biology | Year: 2015
The small-toothed palm civet Arctogalidia trivirgata is a small, arboreal civet belonging to the subfamily Paradoxurinae (Viverridae) that is found in northeast India, southern China, and Southeast Asia. This is an understudied species with a debated taxonomy. Variation in coat colour and pattern has driven authors to describe numerous taxa of this civet species, but no recent taxonomic revision and no intraspecific molecular study have been conducted. We sequenced three mitochondrial and one nuclear markers in order to study the geographical genetic structure of the small-toothed palm civet and to evaluate the genetic divergence between different populations, and we examined various morphological features. Our molecular results showed that the small-toothed palm civet forms two divergent clades: Clade 1: mainland Southeast Asia, Sumatra and nearby small islands, and Java; and Clade 2: Borneo. Further investigations are needed to verify the possible specific status of these two clades. The populations north of the Isthmus of Kra are characterized by a white ear tip and form a separate clade from the populations south of the Isthmus of Kra, but their genetic divergence does not warrant a specific status. The Javan small-toothed palm civet was found to have a low genetic divergence to the nearby populations within Clade 1. Further studies are needed in order to confirm these results and to revise the taxonomy of the small-toothed palm civet. © 2015 Deutsche Gesellschaft fü Säugetierkunde.
Biotope | Date: 2010-08-05
Disclosed is a method for monitoring an installation having a first level of dangerousness for an animal species in a first operating state (E_(1)), the method including a step (107) in which the installation is switched to a second operating state (E_(2)) in which the installation has a second lower level of dangerousness. The installation is switched to the second operating state on the basis of at least one criterion linked to the activity of the animal species or on the basis of a multivariate model for predicting the activity. Also disclosed is a computer program including instructions for implementing the method, to a device for implementing same, and to a system including such a device.
PubMed | Impasse Jean Galot, CNRS Guyane USR3456, Biotope, Pointe Maripa and Royal Belgian Institute Of Natural Sciences
Type: | Journal: Zootaxa | Year: 2014
We describe a new Pristimantis from French Guiana, northern South America, which is mainly distinguished from known phenotypically related congeners (i.e. species from the polyphyletic unistrigatus species group) occurring at low and middle elevations in the Guiana Shield by the combination of a distinct tympanum, a lower ratio of tibia vs. hand length, a reddish groin region, and a distinct advertisement call consisting of clusters of generally four short notes. The new species inhabits pristine primary forests on the slopes of isolated massifs reaching more than 400 m elevation, and seems not to occur below ca. 200 m above sea level. Such a sharp altitudinal limit suggests a strong influence of thermal variation on the distribution of the species, and therefore a potential sensitivity to climate change. With only nine isolated populations documented so far, the new species should be prioritized for conservation. Historical climate fluctuations during the Quaternary are likely responsible for the distribution pattern of the new species.
Gaucherand S.,IRSTEA |
Schwoertzig E.,University of Strasbourg |
Schwoertzig E.,CNRS Alpine Ecology Laboratory |
Clement J.-C.,CNRS Alpine Ecology Laboratory |
And 2 more authors.
Environmental Management | Year: 2015
Given the recent strengthening of wetland restoration and protection policies in France, there is need to develop rapid assessment methods that provide a cost-effective way to assess losses and gains of wetland functions. Such methods have been developed in the US and we tested six of them on a selection of contrasting wetlands in the Isère watershed. We found that while the methods could discriminate sites, they did not always give consistent rankings, thereby revealing the different assumptions they explicitly or implicitly incorporate. The US assessment methods commonly use notions of “old-growth” or “pristine” to define the benchmark conditions against which to assess wetlands. Any reference-based assessment developed in the US would need adaptation to work in the French context. This could be quite straightforward for the evaluation of hydrologic variables as scoring appears to be consistent with the best professional judgment of hydrologic condition made by a panel of French local experts. Approaches to rating vegetation condition and landscape context, however, would require substantial reworking to reflect a novel view of reference standard. Reference standard in the European context must include acknowledgement that many of the best condition and biologically important wetland types in France are the product of intensive, centuries-long management (mowing, grazing, etc.). They must also explicitly incorporate the recent trend in ecological assessment to focus particularly on the wetland’s role in landscape-level connectivity. These context-specific, socio-cultural dimensions must be acknowledged and adjusted for when adapting or developing wetland assessment methods in new cultural contexts. © 2015, Springer Science+Business Media New York.