Ebdecogenes.ebd.csic.es

Monitoring ecosystem responses

A NOVEL SPATIO TEMPORAL SCALE TO INTEGRATE OCEANOGRAPHIC VARIABLES
INTO MARINE ANIMALS
, Francisco Ramírez1, Manuela González-Forero1 Peter Dann2 and André 1Doñana Biological Station (EBD-CSIC), Spain; 2Phillip Island Nature Parks (PINP,
Abstract
Matching peak food availability and reproduction is essential for the energy demands of animals living in high latitudes. Recently, climatic variability has added a newer and additional difficulty to reach this matching by affecting oceanic processes, impacting marine productivity and shifting the spatial-temporal availability of prey, with severe consequences in the reproductive performance of predators. Detecting these relationships require understanding at which scales animals perceive and integrate environmental information. Marine systems are highly dynamics and marine predators, such as seabirds, are likely affected by changes in marine productivity in their foraging areas, but also in surrounding water masses flowing to their foraging grounds. An important challenge is to determine a suitable spatial-temporal scale at which marine predators interact with their environment. Here we test a novel way to identify water masses flowing to the seabirds foraging grounds using connectivity analysis based on circuit theory which we applied to marine currents. Monthly average Chl-a concentrations (a proxy of marine productivity) were extracted from previously defined marine areas (according to connectivity analysis performed on a monthly basis) for the 1993-2009 time period. We argue that these new connectivity areas integrate intra- and inter-annual dynamics of the oceanographic circulation. These areas provide a more meaningful zone influencing marine predators than just considering predator spatial distribution itself and a useful tool to understand how energy moves from primary production to higher trophic levels in face of climatic Monitoring ecosystem responses

HABITAT NICHE OF TWO CLOSELY-RELATED SEABIRDS BREEDING IN SYMPATRY
, Joan Navarro2, Laura Cardador3, Francisco Ramírez1, Akiko Kato4, Beneharo Rodríguez5, Yan Roupert-Coudert4, Manuela G. Forero1 1Estación Biológica de Doñana, EBD-CSIC; 2Institut de Ciències del Mar (ICM-CSIC); 3Grup d’Ecologia del Paisatge, Àrea de Biodiversitat, Centre Tecnològic Forestal de Catalunya (CTFC); 4Université de Strasbourg, IPHC – CNRS; 5SEO/BirdLife
Abstract
Marine ecosystems are different from their terrestrial or freshwater counterparts since they are openness, highly dynamics and spatially heterogeneous. Fortunately, ocean observing satellites have launched a new era of marine discovery providing information on several physical and biological features throughout long-time periods (up to decades) and over broad areas. Accordingly, remote sensing approaches have emerged as powerful tools for tracing global-change related variations in those environmental features likely driving marine productivity patterns. On the other hand, seabirds often distribute themselves according to oceanographic features likely driving the abundance and distribution of prey species. Tracking seabirds in their foraging zones is therefore a major input to integrated marine studies, since may inform on spatiotemporal changes in marine productivity patterns. Here, we present a case study where remote sensing information on oceanographic features was combined with GPS-derived information on the foraging distribution of pelagic seabirds to test for their usefulness as tracers of marine productivity patterns, while accounting for potential constraints ascribed to their central place foraging behavior while breeding. In particular, we analyzed the foraging strategies of two closely related species of shearwaters breeding in sympatry in the Mediterranean (Scopoli’s shearwater Calonectris diomedea and Cory’s shearwater C. borealis), throughout their entire reproductive cycle (i.e. incubation and chick-rearing stages). As expected, both shearwater species exploited highly productive and persistent marine areas, located at shal ow waters near the colony. Energy demands and constraints ascribed to different breeding stages also played a relevant role in modulating the at sea distribution of shearwaters. The foraging areas of the two species broadly overlapped during the incubation stage. During chick-rearing, Scopoli’s shearwaters were highly constrained in their foraging distance from the colony, whereas Cory’s shearwaters kept its foraging area broader, thus segregating in its foraging strategies from its potential Monitoring ecosystem responses

SIERRA NEVADA GLOBAL CHANGE OBSERVATORY: MONITORING POPULATION AND
ECOSYSTEM RESPONSES UNDER A GLOBAL CHANGE SCENARIO
, José Miguel Barea Azcón1, Ignacio Henares Civantos2, Blanca 1Agencia de Medio Ambiente y Agua, Spain; 2Consejería de Agricultura, Pesca y Medio Ambiente. Parque Nacional y Natural Sierra Nevada, Spain; 3University of Granada,
Abstract
Since 2007 Sierra Nevada Global Change Observatory is accomplishing a monitoring programme designed to detect changes in terrestrial and freshwater ecosystems functioning in a global change (hereafter GC) scenario. The ultimate objective of this initiative is to gather the necessary information to identify in advance the impacts of GC, in order to design management measures to minimize those impacts and help ecosystems to adapt to the new changing situations. With that purpose, almost 50 different monitoring methodologies, scientifically validated by experts in each topic, have been tested. They have been designed fol owing the guidelines of GLOCHAMORE The main GC drivers detected in this Mediterranean high mountain ecosystem are climate and land use changes. With respect to climate main changes can be summarized as follow: a rise in temperature over recent decades (especially the minimum) and a steady trend of precipitation patterns and substantial changes in snow cover (decrease in the snow cover permanence as a result of later first snowfal event and earlier latest). Moreover, land uses have also changed considerably in recent decades, in which a decrease in agroecosystem extension has been detected, together with forest evolution to more mature structures and a progressive expansion of scrubland over the timber line. In this contribution we analyze the trend of these CG drivers over the ecosystems of Sierra Nevada National and Natural Park. The main topics have been grouped under the fol owing findings: (i) temporal and altitudinal trends in species and communities distribution and phenology, (i ) implications of climate change on ecosystem functioning and biotic interactions, (iii) policy and management strategies aimed to mitigate CG impacts and (iv) impact of ecosystem Monitoring ecosystem responses

HUMAN IMPACTS PROMOTE THE ACCUMULATION OF INORGANIC FORMS IN GLOBAL
DRYLANDS
, Fernando T. Maestre1, Antonio Gallardo2, Matthew A. Bowker3, Ana Prado Comesaña2 and network-EPES-BIOCOM -EBN-49 authors from 26 1Universidad Rey Juan Carlos-Departamento de Biologia y Geologia; 2Universidad Pablo de Olavide-Departamento de Sistemas Fisicos, Quimicos y Naturales; 3Northern
Abstract
Human exploitation and climate change are changing the inputs to and losses from the N cycle in terrestrial ecosystems. As the global human population continues to grow, we will rely increasingly on marginal lands such as drylands for the production of food, wood and biofuels. These lands already cover about 41% of Earth’s land surface and support over 38% of the global human population. While much is known about how abiotic factors such as climate and soil texture control each component of the N cycle, it is less clear how the fingerprint of human impacts is changing the soil total N concentration and the dominance of N forms. We conducted an observational global field study to evaluate how human impacts and aridity, together with biotic (plant cover) and abiotic (pH and soil texture) factors determine the concentration of total N, dissolved organic (DON) and inorganic N (ammonium and nitrate), the DON:DIN ratio and the potential net mineralization rate in dryland soils. Our result suggested that human and climate change impacts will increase and decrease the total soil N, respectively. However, because of the observed negative relationship between aridity and human impacts, these results may shift along the studied aridity gradient. Both increasing aridity and human impacts will enhance the mineralization rates and inorganic N (ammonium andnitrate) in drylands soils. These inorganic N forms are highly susceptible to end up pol uting water bodies and in the atmosphere through processes such as leaching, runoff and denitrification. Monitoring ecosystem responses

DRY UP OF TEMPORARY PONDS IN DOÑANA NATIONAL PARK (SW SPAIN:
MONITORING LONG-TERM WETLAND DYNAMICS WITH LANDSAT IMAGES

David Aragonés and Javier Bustamante
Doñana Biological Station (EBD-CSIC), Spain
Abstract
Doñana National Park holds some of the most important wetlands in Europe. One of them is the system of temporary ponds and shal ow lakes in the sand dunes resulting from the discharge of a big aquifer. Their water level is directly related to variations in the groundwater table. Water extraction for human use is currently threatening the preservation of these wetlands. Water pumping for agriculture and tourist resorts have caused important drops in the groundwater table level, with the consequence of a decrease in the hydroperiod of temporary wetlands and even the complete dry up of some big ponds. Because there is no historical data on variation in flood level of Doñana temporary ponds, we used Landsat satellite images to study the flooding and dry up seasonal dynamics of this system in the last thirty years. We used more than 200 radiometrical y normalized Landsat scenes (TM and ETM +) to evaluate historical changes in the flood level of the pond system (from 1985 to 2012). For each image we calculated the extension of the flooded area using a simple threshold method on the TM5 band (1.55-1.75 um) reflectivity and estimated the duration of the flood season of each temporary pond and the the number of years larger ponds dried up. The relationship of these variables with annual rainfall revealed recent changes in the water regime of the most permanent and largest ponds of the system. Thirty years ago, these ponds were mainly sustained by the groundwater, and their extension, and consequently their water level, did not fluctuate widely. Due to overexploitation of the aquifer, in the two more recent decades, the extension of these big ponds has fluctuated widely in response to variation in annual rainfall, most of them reaching desiccation in dry years. Monitoring ecosystem responses

LABILE CARBON ENRICHMENT AS A LOW-COST TOOL FOR CONTROLLING THE
EUTROPHICATION IN MEDITERRANEAN INLAND WATER IN A GLOBAL CHANGE

Presentación Carrillo and Juan Manuel Medina-Sánchez

Abstract
Human activities, by altering nutrient fluxes (increasing loads of P and N), are promoting eutrophication of aquatic ecosystems. As consequence, algal growth is enhanced, resulting in blooms of potential y harmful algae which alter trophic web dynamics, and decrease ecosystem services. Several approaches to reduce the problems caused by eutrophication processes have been proposed, but few have been successful when applied to fluctuating inland-waters. We investigate a low-cost biomanipulation approach at microbial scale based on experimental increasing load of al ochthonous labile organic carbon to promote competitive growth of heterotrophic food web against phytoplankton. The aim is to enhance biomass and nutrient transfer to higher trophic levels, thus favoring a clear-water stable state. We provide results of an in situ experimental setup performed in a Mediterranean natural hypereutrophic lake (Santa Olalla lake in Doñana National Park, Spain) designed to obtain the thresholds of labile organic carbon inputs which maximize changes in the structure and function of planktonic microbial community. Results showed a decrease in DOC in two of the five different carbon enrichment treatments suggesting a bacterial consumption. Additional y, a decrease in Chla was found during the first experimental week in these treatments, suggesting bacteria could take advantage of available nutrient consumption. However, bacterial abundance did not increase in the expected extent, probably due to an increase of top-down pressure by (micro) zooplankton communities. We conclude that labile carbon enrichment was able to promote a decreasing trend of phytoplankton dominated by cyanobacteria responsible of blooms Monitoring ecosystem responses

THE ROLE OF FOREST STRUCTURE AND PREVIOUS LAND USE IN DETERMINING THE
ECOPHYSIOLOGICAL TRAITS OF PINUS NIGRA POPULATIONS FROM SOUTHERN SPAIN
AND NORTHERN MOROCCO UNDER A CLIMATE CHANGE SCENARIO

, Juan Carlos Linares1, Jose Antonio Carreira2 and Benjamin Viñegla2
1Pablo de Olavide University, Spain; 2University of Jaen, Spain
Abstract
Forest structural attributes are determined, at the stand level, by abiotic (climatic, edafic and topographic) and biotic factors (competence and resource use) as well as by perturbation attributes. The final structure has been modulated by previous environmental conditions and also previous land use. All these previous conditions will determine the interactions among individuals and among them and the available resources. Moreover, the structural characteristics will modulate and determine the response of forest ecosystems to perturbations in the long term and to long-term changes in the environmental conditions related to Global Climate Change. Therefore, highly densified structures, that are also lacking of heterogeneous properties such as small ranges of variation in size and age classes or spatial heterogeneity, may be more susceptible to unfavourable conditions or extreme climatic events. This absence of adaptive capacity to environmental changes will be especially important in the case of species that distribute near their tolerance limits, such relict conifer species, being this effect more deleterious under increasing temperature and decreasing precipitation levels associated to global climate change. In this work we have examined the ecophysiological response of different Pinus nigra forests, located in Southern Spain (Sierra Magina and Sierra de Cazorla (at two elevations) Natural Parks) and Northern Morocco (Talassemtane National Park), with different structural attributes due to the past land use and management policies. Thus, variables related to C (photosynthesis and respiration rates) and water balance (stomatal conductance and xylematic water potential) were analysed, showing an increasing trend in the intrinsic water use efficiency during the summer period with a concurrent strategy of reduction of the photosynthetic and the stomata conductance rates, although these trends are modulated by the stand structure. Moreover, the Mediterranean climatic seasonality determines the synthesis of the non structural carbohydrates pool during the absence of the drought stress (autumn and winter), by means of increasing C assimilation rates. Monitoring ecosystem responses

THE POTENTIAL IMPACTS OF GLOBAL CHANGE ON THE DISTRIBUTION OF PINUS
SYLVESTRIS L., P. NIGRA ARNOLD AND ABIES PINSAPO BOISS. IN THE BAETIC RANGE
(ANDALUSIA, SPAIN): A HIGH RESOLUTION PREDICTIVE MODEL.

Abstract
Taiga or boreal forest is the largest biome in the world being well distributed at high latitudes in the northern hemisphere. At lower latitudes, as the Mediterranean basin, these forests lose prominence remaining strongholds since the latest ice ages. Thus, in the southern of the Iberian Peninsula it has been studied the potential distribution of three high mountain conifers using spatial distribution models (SDMs): Abies pinsapo, Pinus sylvestris and Pinus nigra. The development of the models has been carried out by means of a mesh of points with a resolution of 250 m, in which 12 explanatory variables were used: 4 topographical (elevation, slope, transformed aspect and curvature) and 8 environmental (obtained from monthly data of temperature, rainfall and evapotranspiration). This mesh also contains information about presence/absence of the three involved species. Once the mesh is ready, a model ing process by means of binary logistic regression has been carried out, resulting a formulae which can predict in a given point the suitability of presence for these species. Moreover, a potential distribution map with future environmental conditions at the end of the twenty-first century was carried out to each species, obtaining distribution maps in the context of global change scenarios. The aim of this work was to compare both potential distribution maps in the present and in the future and analyse which explanatory variables were more influenced in this new environmental conditions. Monitoring ecosystem responses

BIOLOGICAL SOIL CRUSTS AND WETTING EVENTS: EFFECTS ON SOIL N AND C CYCLES
ntonio Gallardo and Ana Prado-Comesaña
Abstract
Biological soil crusts (BSC) communities are key biotic components of arid and semiarid ecosystems that control many functional processes including nitrogen (N) and carbon (C) cycling. On these ecosystems, biological activity is controlled by water inputs through soil wetting-drying cycles. With expected climate change leading to increase precipitation variability, the study of the effect of length of wetting event on nutrients soil in BSCs areas is becoming crucial. To assess the response of these ecosystems to changing length of wetting event, we applied three different watering treatments to two microsites in a microcosm experiment: BSC and bare soil. We analyzed multiple variables related to N (N in microbial biomass [MB-N], dissolved organic nitrogen [DON], NH4+-N, NO3--N, Resin-NH4+-N and Resin-NO3--N) and C (phenols and carbohydrates) cycling. For all treatments, DON concentration decreased faster in BSC than in bare soil, while NO3- showed the inverse response, with longer increased under bare soil. Increases of NH4+ were only perceptible under BSC. Net changes rates of NH4+, NO3-, phenols and carbohydrates increased for the longer wetting events in BSC, while only NH4+ and carbohydrates rates showed the same trend in bare soil. We also found a decrease of MB-N and DON change rates for BSC and bare soil respectively in longer wetting events. Our results showed that longer wetting events produced higher mineral N and organic C production rates, but lower organic N production rates, which suggest that longer wetting events may be related to an enhancement in the microbial metabolic rates such as both decomposition and mineralization rates. This trend is more obvious in BSC than in bare soil, suggesting that BSC communities may benefit these microbial activities. Our data strongly suggest that soil N and C cycling is markedly affected by the length of wetting event and the presence of BSC, and such changes could alter future soil community structure and Monitoring ecosystem responses

LIGHT MEASUREMENT IN TERRESTRIAL ECOSYSTEMS USING PHOTODEGRADING

, Jorge Duran2, Heather A. Bechtold2, Peter M. Groffman2 and Emma J.
1Pablo de Olavide University, Spain; 2Cary Institute of Ecosystem Studies-
Abstract
Incoming solar radiation is the main determinant of terrestrial ecosystem processes, such as primary production, litter decomposition, or soil mineralization rates. Light in terrestrial ecosystems is spatial y and temporal y heterogeneous due to the interaction among sunlight angle, cloud and tree-canopy structure. To integrate this variability, a high number of measurements are needed, but tools to do this are expensive and limited. We used two photodegrading fluorescent organic dyes, rhodamine WT (RWT) and fluorescein, for the quantification of light. We measured dye photodegradation as the decrease in fluorescence across an irradiance gradient from full sunlight to deep shade and correlated it to accumulated light measured with PAR quantum sensors. RWT and fluorescein photodegradation fol owed an exponential decay curve with respect to accumulated light. RWT degraded slower than fluorescein but remained unaltered after exposure to continuous natural temperature changes. Dyes showed no degradation when exposed to control ed high temperatures. RWT and fluorescein can be used to measure light under a varying range of light conditions. This method is useful to integrate solar radiation over time and to measure light simultaneously at different locations, and might be a better alternative to the expensive and time consuming traditional light measurement methods. Monitoring ecosystem responses

FOREST HETEROGENEITY AT THE LANDSCAPE LEVEL IN PINUS
NIGRA FORESTS FROM SOUTHERN SPAIN AND NORTHERN MOROCCO

Benjamin Viñegla1, Victor Lechuga1, Juan Carlos Linares2 and Jose Antonio Carreira1
1University of Jaen, Spain; 2Pablo de Olavide University, Spain
Abstract
In forest ecosystems the processes that take place at the individual or stand level are integrated in higher spatial and temporal scale processes, giving as a result the dynamics of the ecosystems at the landscape scale. In order to evaluate changes at the landscape level, it is necessary to characterize the patterns at this higher scale than the individual or the stand ones. Final y, these patterns and interactions wil change along time, mainly as a consequence of land use, generating spatial heterogeneity, which determines the ecological processes. Therefore, the landscape’s pattern has a great influence in its ecological characteristics, and it is essential to quantify spatial heterogeneity in order to understand landscape’s structure and sustainability in the long term, specially under changing climatic conditions in a Global Climate Change scenario. However, due to its intrinsic complexity, a landscape cannot be characterized by means of a single variable and, therefore, it is necessary to analyze a series of variables related to landscape’s composition and configuration. In this work we have evaluated, at the landscape level, the evolution along time of Pinus nigra forest landscapes, located in Southern Spain (Sierra Magina and Sierra de Cazorla (at two elevations) Natural Parks) and Northern Morocco (Talassemtane Natural Park), showing different structural attributes due to the past land use and management policies. Thus, we have used several indexes that characterize the spatial structure of forest patches in order to evaluate the long term trends of forest cover but also of the heterogeneity and fragmentation patterns, taking into account variables related to landscape’s composition, such as density or mean patch size, and to landscape’s configuration, such as the fractal dimension of the landscape. In all the localities a strong increase of forest cover at the landscape level occurred during the last 60 years, while at the same time landscape fragmentation and heterogeneity was reduced. However, landscape complexity, estimated by means of the fractal dimension of the landscape, has been found to be higher in Talassemtane, where low intensity traditional land uses have modulated the landscape elements, promoting the shape complexity of patches. On the other hand, a relative homogeneous landscape structure has been found where intense management and conservation practices have
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Source: http://ebdecogenes.ebd.csic.es/Monitoring-ecosystem-responses.pdf