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Mapping Mediterranean Wetlands With Remote Sensing: A Good-Looking Map Is Not Always a Good Map
No full textWetlands are a key habitat within the Mediterranean biodiversity hotspot and provide important ecosystem services for human well-being. Remote sensing (RS) has significantly boosted our ability to monitor changes in Mediterranean wetlands, especially in areas where little information is being collected. However, its application to wetlands has sometimes been flawed with uncertainties and unrecognized errors, to a large extent due to the inherent and specific ecological characteristics of Mediterranean wetlands. We present here an overview of the state of the art on RS techniques for mapping and monitoring Mediterranean wetlands, and the remaining challenges: delineating and separating wetland habitat types; mapping water dynamics inside wetlands; and detecting actual wetland trends over time in a context of high, natural variability. The most important lessons learned are that ecologists\u27 knowledge need to be integrated with RS expertise to achieve a valuable monitoring approach of these ecosystems
Environmental and anthropogenic factors affecting the increasing occurrence of shark-human interactions around a fast-developing Indian Ocean island
No full textUnderstanding the environmental drivers of interactions between predators and humans is critical for public safety and management purposes. In the marine environment, this issue is exemplified by shark-human interactions. The annual shark bite incidence rate (SBIR) in La R?union (Indian Ocean) is among the highest in the world (up to 1 event per 24,000?hours of surfing) and has experienced a 23-fold increase over the 2005-2016 period. Since 1988, 86% of shark bite events on ocean-users involved surfers off the leeward coast, where 96% of surfing activities took place. We modeled the SBIR as a function of environmental variables, including benthic substrate, sea temperature and period of day. The SBIR peaked in winter, during the afternoon and dramatically increased on coral substrate since the mid-2000s. Seasonal patterns of increasing SBIR followed similar fluctuations of large coastal shark occurrences (particularly the bull shark Carcharhinus leucas), consistent with the hypothesis that higher shark presence may result in an increasing likelihood of shark bite events. Potential contributing factors and adaptation of ocean-users to the increasing shark bite hazard are discussed. This interdisciplinary research contributes to a better understanding of shark-human interactions. The modeling method is relevant for wildlife hazard management in general
Long-term changes (1990-2015) in the atmospheric deposition and runoff water chemistry of sulphate, inorganic nitrogen and acidity for forested catchments in Europe in relation to changes in emissions and hydrometeorological conditions
No full textThe international Long-Term Ecological Research Network (ILTER) encompasses hundreds of long-term research/monitoring sites located in awide array of ecosystems that can help us understand environmental change across the globe. We evaluated long-term trends (1990-2015) for bulk deposition, throughfall and runoff water chemistry and fluxes, and climatic variables in 25 forested catchments in Europe belonging to the UNECE International Cooperative Programme on IntegratedMonitoring of Air Pollution Effects on Ecosystems (ICP IM). Many of the IMsites form part of themonitoring infrastructures of this larger ILTER network. Trends were evaluated for monthly concentrations of non-marine (anthropogenic fraction, denoted as x) sulphate (xSO4) and base cations x(Ca+Mg), hydrogen ion (H+), inorganic N (NO3 and NH4) and ANC (Acid Neutralising Capacity) and their respective fluxes into and out of the catchments and for monthly precipitation, runoff and air temperature. A significant decrease of xSO4 deposition resulted in decreases in concentrations and fluxes of xSO4 in runoff, being significant at 90% and 60% of the sites, respectively. Bulk deposition of NO3 and NH4 decreased significantly at 60-80% (concentrations) and 40-60% (fluxes) of the sites. Concentrations and fluxes of NO3 in runoff decreased at 73% and 63% of the sites, respectively, and NO3 concentrations decreased significantly at 50% of the sites. Thus, the LTER/ICP IM network confirms the positive effects of the emission reductions in Europe. Air temperature increased significantly at 61% of the sites,while trends for precipitation and runoffwere rarely significant. The sitespecific variation of xSO4 concentrations in runoff wasmost strongly explained by deposition. Climatic variables and deposition explained the variation of inorganic N concentrations in runoff at single sites poorly, and as yet there are no clear signs of a consistent deposition-driven or climate-driven increase in inorganic N exports in the catchments
Detection of windthrows and insect outbreaks by L-band SAR: A case study in the Bavarian Forest National Park
No full textNatural disturbances significantly influence forest ecosystem services and biodiversity. Accurate delineation and early detection of areas affected by wind and insect outbreaks are crucial for guiding management decisions. To this end, past studies relied mostly on passive sensors (e.g., optical), and active sensors (i.e., radar) were rarely used. This study used L-band space-borne synthetic aperture radar (SAR) within a change-detection framework to delineate forested areas affected by wind and insect disturbances. The results showed that changes in backscatter relate to damage caused by wind and insect outbreaks. Overall accuracies of 69-84% and 65-88% were obtained for delineation of areas affected by wind damage and insect outbreaks, respectively, depending on the acquisition date and environmental conditions. Areas susceptible to insect outbreaks or experiencing the initial outbreak phase (green) were detected with lower accuracies (64-74%). It is expected that L-band space-borne SAR data can be applied over larger areas and ecosystem types in the temperate and boreal regions to delineate and detect damaged areas
Endemic vascular plants in the high mountains of the Sierra Nevada National Park (Spain)
No full textThe Sierra Nevada National Park contains an outstanding number of endemic vascular plant species, especially at higher elevations. We sampled the floristic composition of 20 sites along an elevational gradient from 2000 up to 3482 m a.s.l. Thereby, patterns of endemicity, species richness and leaf colours had been investigated to quantify diversity aspects of endemics. This study is part of the H2020 ECOPOTENTIAL project and improves the link between high-elevation endemic species and their climatic endangerment with modern sampling approaches (magnetic site marking, remote sensing products)
CORINE for large-scale monitoring of PAs in Europe
No full textCORINE Land Cover Change provides official European land cover monitoring. Here, we investigate how CORINE can be used for large-scale monitoring of Protected Areas (PAs) in Europe. Main processes observed include changes from and to ?forest and semi-natural vegetation?. Rates of change differ significantly between PAs and their direct vicinity, as well as between protection statuses of PAs. Comparison with alternative data will show that shortcomings due to the spatial and categorical resolution of CORINE might be overcome for European-wide PA monitoring
Negotiating local versus global needs in the International Long Term Ecological Research Network\u27s socio-ecological research agenda
No full textOver the past decade, long-term socio-ecological research (LTSER) has been established to better integrate social science research and societal concerns into the goals and objectives of the International Long-Term Ecological Research (ILTER) network, an established global network of long-term ecologicalmonitoring sites. TheHorizon 2020 eLTER project, currently underway, includes as one of its key objectives to evaluate the performance of LTSER platforms. This article reflects part of this evaluation: six LTSER platformswere assessed through site visits of the lead author, coupledwith reflections and insights of the platform managers, who are also co-authors.We provide background for the mission and goals of LTSER, then assess the six international LTSERplatforms-Baltimore Ecosystem Study LTER, USA; Braila Island LTSER, Romania; Cairngorms LTSER, UK;Do?ana LTSER, Spain;OmoraEthnobotanical Park CapeHorn LTER,Chile; and Sierra Nevada LTSER, Spain. While based on a strong theoretical foundation in socio-ecological research, there has been a steep learning curve for scientists applying the concept in practice at LTSER platforms. We show positive impacts that have been achieved, including contributions to policy, land-use planning, and natural resourcemanagement.Weexplain key aspects of LTSERplatforms that have proven challenging, includingmanagement, interdisciplinary integration, and stakeholder collaboration.Wecharacterize the tensions between top-down desires for network harmonization, bottom-up demands such as local policy relevance, and platform-level constraints such as time and budget. Finally,we discuss challenges, such as local context dominating the character of LTSER platforms, and the fact that scientists are often disincentivized from engaging in transdisciplinary science. Overall, we conclude that while the internationalnetwork offers important advantages to itsmembers, a more productive balance between local and global goals could be achieved, and membersmay need to temper their expectations of what the network can and cannot offer at the local level
Time series analysis of vegetation-cover response to environmental factors and residential development in a dryland region
No full textLand-use changes as a result of residential development often lead to degradation and alter vegetation cover (VC). Although these are worldwide phenomena, sufficient knowledge about anthropogenic effects caused by various populated areas in dryland ecosystems is lacking. This study explored anthropogenic development in rural areas and its effects on the conservation of protected areas in drylands, focusing on the change in VC, the reasons, extent, and the drivers of change. We propose a novel framework for exploring VC change (VCC) as a function of environmental and human-driven factors including different types of populated areas in drylands. As a case study, we used a 30-year time series of Landsat satellite images over the arid region of Israel to analyze spatiotemporal VCC. The temporal analysis involved the Contextual Mann-Kendall significance test and spatial analysis to model clustering of VCC. A Gradient Boosted Regression machine learning algorithm was applied to study the relative influence of environmental and human-driven factors on VCC. In addition, we usedANOVAto examine differences between the effects of three types of populated areas on the spatiotemporal trends of VC. The results show that the most influential environmental variable on VCC was elevation (relative contribution of 17%), followed by slope (14.8%) and distance from populated areas (14.6%). Moreover, different types of populated areas affected VC differently with varying distances from residential centroids. The nature reserves increased VC positively and significantly, while livestock settlements had a negative effect. Change in vegetation was mostly confined to the stream network and occurred in lower elevations. The study demonstrates how different land-use practices alter the landscape in terms of VC and differ in their extents, patterns, and effects. With the expected growth in population and residential development worldwide, the proposed framework may assist conservation managements and policy makers in minimizing environmental degradation in drylands
Discriminative word learning is sensitive to inflectional entropy
No full textPsycholinguistic evidence based on inflectional and derivational word families has emphasised the combined role of Paradigm Entropy and Inflectional Entropy in human word processing. Although the way frequency distributions affect behavioural evidence is clear in broad outline, we still miss a clear algorithmic model of how such a complex interaction takes place and why. The main challenge is to understand how the local interaction of learning and processing principles in morphology can result in global effects that require knowledge of the overall distribution of stems and affixes in word families. We show that principles of discriminative learning can shed light on this issue. We simulate learning of verb inflection with a discriminative recurrent network of specialised processing units, whose level of temporal connectivity reflects the frequency distribution of input symbols in context. We analyse the temporal dynamic with which connection weights are adjusted during discriminative learning, to show that self-organised connections are optimally functional to word processing when the distribution of inflected forms in a paradigm (Paradigm Entropy) and the distribution of their inflectional affixes across paradigms (Inflectional Entropy) diverge minimally
Atmospheric deposition in European Forests in 2016
No full textStudying the effects of atmospheric pollution to forest ecosystems requires an evaluation of air quality and of the amount of pollutants carried to the forests by atmospheric deposition. Pollutant flux towards ecosystems through deposition mainly follows two pathways: wet deposition of compounds dissolved in rain and snow and dry deposition of particulate matter through gravity or filtration, for example by forest canopy. Pollutant deposition shows a relatively high local variability, related to the distribution of pollutant sources and the local topography, and in-situ measurement is needed to obtain accurate evaluations and to validate model estimates. In 2016, the chemical composition of atmospheric deposition was measured in 276 Level II permanent plots. In this report, we focus on acidifying, buffering, and eutrophying compounds. High throughfall deposition of nitrate was mainly found in central Europe (Germany, Switzerland), Denmark, and Belgium, while for ammonium high deposition was also found in northern Italy. The area of high deposition is smaller for sulphate, including some plots in Germany and Poland. High values were also measured in Belgium, but they are partially due to deposition of marine aerosol, and they are less evident after sea-salt correction. High deposition in southern Italy may be related to local anthropogenic sources and to volcanic contribution. Calcium, potassium, and magnesium deposition can buffer the acidifying effect of atmospheric deposition. High values of calcium throughfall deposition were reported for southern Europe, where it is often related to the deposition of Saharan dust, and for Eastern Europe. The correction for the marine contribution does not affect its spatial pattern. On the contrary, for magnesium, the number of sites with the highest values is markedly reduced by the sea salt correction