Tablas De Daimiel National Park Research Articles

Pesticides in water and sediments from natural protected areas of Spain and their associated ecological risk

In the last years, issues related to intensive agriculture have been found in protected areas potentially harming wildlife. This study aimed to analyze a wide range of pesticides in water and sediments of two protected areas namely Doñana Natural Park (DNP) and Tablas de Daimiel National Park (TDNP) performing an environmental risk assessment in order to highlight potential risks to living organisms derived from pesticide burden. Higher pesticide load was found in DNP than TDNP with similar distribution profiles, with pyrethroid insecticides (PYRs) the main detected class. Particularly problematic are two PYRs, cyhalothrin and fenvalerate, which were detected at high concentrations that can pose a high risk to aquatic organisms. In addition, despite being detected at lower concentrations, the presence of chlorpyrifos, cypermethrin, and permethrin in water, and of chlorpyrifos, dicofol, and diflufenican in sediments, must be taken into account due to their potential risks for aquatic organisms. Moreover, some banned pesticides such as dimethoate, terbutryn, diazinon, and tricyclazol were detected in water at levels which deserve further investigation to assess their potential sources, including potential illegal practices.

Low signs of territorial behavior in the Eurasian otter during low-water conditions in a Mediterranean river

The Eurasian otter Lutra lutra is a territorial semi-aquatic carnivore usually found at low densities in rivers, coastal areas, and wetlands. Its diet is based on prey associated with aquatic environments. Mediterranean rivers are highly seasonal, and suffer reduced flow during the summer, resulting in isolated river sections (pools) that sometimes can be left with a minimal amount of water, leading to concentrations of food for otters. To our knowledge, this process, which was known to field naturalists, has not been accurately described, nor have otter densities been estimated under these conditions. In this study, we describe the population size and movements of an aggregation of otters in an isolated pool in the Guadiana River in the Tablas de Daimiel National Park (central Spain), which progressively dried out during the spring–summer of 2022, in a context of low connectivity due to the absence of circulating water in the Guadiana and Gigüela rivers. Using non-invasive genetic sampling of 120 spraints collected along 79.4 km of sampling transects and spatial capture-recapture methods, we estimated the otter density at 1.71 individuals/km of river channel length (4.21 individuals/km2) in a progressively drying river pool, up to five times higher than previously described in the Iberian Peninsula. The movement patterns obtained with the spatial capture-recapture model are not quite different from those described in low density, which seems to indicate a wide home range overlap, with low signs of territoriality.

Ecological degradation of a fragile semi-arid wetland and the implications in its microbial community: The case study of Las Tablas de Daimiel National Park (Spain)

Las Tablas de Daimiel National Park (TDNP, Iberian Peninsula) is a semi-arid wetland of international significance for waterfowl and serves as a migratory route for various bird species. However, TDNP presents strong anthropization and fluctuating water levels, making it a highly fragile ecosystem. Water physico-chemical parameters and microbial diversity of the three domains (Bacteria-Archaea- Eukarya) were analysed in Zone A and Zone B of the wetland (a total of eight stations) during spring and summer, aiming to determine how seasonal changes influence the water quality, trophic status and ultimately, the microbial community composition. Additionally, Photosynthetically Active Radiation (PAR) was used to determine the trophic status instead of transparency using Secchi disk, setting the threshold to 20–40 μmol/sm2 for benthic vegetation growth. In spring, both zones of the wetland were considered eutrophic, and physico-chemical parameters as well as microbial diversity were similar to other wetlands, with most abundant bacteria affiliated to Actinobacteriota, Cyanobacteria, Bacteroidota, Gammaproteobacteria and Verrumicrobiota. Methane-related taxa like Methanosarcinales and photosynthetic Chlorophyta were respectively the most representative archaeal and eukaryotic groups. In summer, phytoplankton bloom led by an unclassified Cyanobacteria and mainly alga Hydrodictyon was observed in Zone A, resulting in an increase of turbidity, pH, phosphorus, nitrogen, chlorophyll-a and phycocyanin indicating the change to hypertrophic state. Microbial community composition was geographical and seasonal shaped within the wetland as response to changes in trophic status. Archaeal diversity decreases and methane-related species increase due to sediment disturbance driven by fish activity, wind, and substantial water depth reduction. Zone B in summer suffers less seasonal changes, maintaining the eutrophic state and still detecting macrophyte growth in some stations.This study provides a new understanding of the interdomain microbial adaptation following the ecological evolution of the wetland, which is crucial to knowing these systems that are ecological niches with high environmental value.

Sulfur Signature of a Mediterranean Wetland: The Case of Soils of the Inundated Floodplain Area at the Tablas de Daimiel National Park

In the Mediterranean region, numerous wetlands co-exist with competitive agricultural systems. Although wetlands’ hydrology (in water volume, source, and residence time terms) plays a major factor in their ecosystem structure, many of these wetlands have been subjected to different degradation processes. One such case is the Tablas de Daimiel National Park (TDNP), which witnesses one of its most environmentally sensitive times. In this context, scarce information is available on the sulfur (S) contents in this wetland. To diagnose this wetland’s degradation status, 43 soil samples were selected and analyzed to investigate S contents in the surface soils (0 to 30 cm) of the inundated floodplain area of the TDNP. They represent different degrees of exposure to pollutants and exposure to flooding. Sulfur determination was carried out by X-ray fluorescence. The S contents in the area range between 1.85 and 37.15 g kg−1, with a mean value of 13.71 g kg−1, which implies marked variability throughout this wetland. The highest values were observed near the wetland entrance via the Gigüela River, while the lowest ones appeared at its exit, with a relatively uniform gradient from the entrance to the exit. The relatively high S concentrations observed at sites other than the wetland entrance can be probably related to the continuous non-point source contamination with P, N, and S fertilizer applications, via runoff agricultural production systems. The results of this study are essential for understanding and predicting total S variability within the TDNP (Spain), which can interfere with soil management practices.

Trace elements and microbial community composition associated with airborne PM2.5 in wetlands: A case study in Tablas de Daimiel National Park

Tablas de Daimiel National Park (TDNP) is one of the most important wetlands in the Iberian Peninsula. Due to its location near various cities and new industries focused on agricultural waste revalorization, we investigated concurrently the concentrations of particulate matter 2.5 (PM2.5) mass, trace element composition, and associated microbial communities (bacteria and fungi) during a year-long study. The goal of this study was to explore the dependencies among these physicochemical and microbiological parameters on a seasonal time scale. Additionally, we assessed meteorological conditions and back trajectories to shed light on atmospheric mechanisms and sources related to these elements. We found the variability of PM2.5 to be influenced by local meteorological parameters. Through the analysis of crustal enrichment factors (EFs), bivariate correlations, and air mass patterns, we determined that soil resuspension was the primary contributor to elevated metal concentrations in PM2.5 within the park, followed by other minor sources, such as traffic emissions and Sahara dust intrusions. The measured metal levels were used to calculate the ecological risk in the area, resulting in a low ecological risk index (RI) of 52. Shifts in microbial community structure were observed to be mainly driven by changes in air temperature and Cu concentration. The results from this study contribute to a better understanding of the environmental dynamics in TDNP. Taken together, our findings will aid in the development of effective strategies for its conservation and management.

Remote Sensing Temporal Reconstruction of the Flooded Area in "Tablas de Daimiel" Inland Wetland 2000-2021.

Tablas de Daimiel National Park (TDNP) is a unique inland wetland located in the Mancha plain (Spain). It is recognized at the international level, and it is protected by different figures, such as Biosphere Reserve. However, this ecosystem is endangered due to aquifer overexploitation, and it is at risk of losing its protection figures. The objective of our study is to analyze the evolution of the flooded area between the year 2000 and 2021 by Landsat (5, 7 and 8) and Sentinel-2 images, and to assess the TDNP state through an anomaly analysis of the total water body surface. Several water indices were tested, but the NDWI index for Sentinel-2 (threshold -0.20), the MNDWI for Landsat-5 (threshold -0.15), and the MNDWI for Landsat-8 (threshold -0.25) showed the highest accuracy to calculate the flooded surface inside the protected area's limits. During the period 2015-2021, we compared the performance of Landsat-8 and Sentinel-2 and an R2 value of 0.87 was obtained for this analysis, indicating a high correspondence between both sensors. Our results indicate a high variability of the flooded areas during the analyzed period with significant peaks, the most notorious in the second quarter of 2010. Minimum flooded areas were observed with negative precipitation index anomalies since fourth quarter of 2004 to fourth quarter of 2009. This period corresponds to a severe drought that affected this region and caused important deterioration. No significant correlation was observed between water surface anomalies and precipitation anomalies, and the significant correlation with flow and piezometric anomalies was moderate. This can be explained because of the complexity of water uses in this wetland, which includes illegal wells and the geological heterogeneity.

Nutrient enrichment and trace element accumulation in sediments caused by waterbird colonies at a Mediterranean semiarid floodplain.

Waterfowl are vectors of nutrients, metals, and other pollutants (i.e. PCBs and microorganisms) on wetlands and other water bodies, especially when bird population density is high, e.g., in nesting, roosting or breeding periods. This work reports the effects caused by the increase in breeding pairs of herons and cormorants between 2010 and 2014 on sediments in an eutrophic Mediterranean wetland belonging to La Mancha Húmeda Biosphere Reserve. Nutrients, metals, metalloids, and isotopic composition (δ15N and δ13C) were analysed in sediments and faeces at several points in the Tablas de Daimiel National Park (TDNP), as well as in the nearby Navaseca wetland, which receives inputs from a wastewater treatment plant (WWTP). Sediments from Navaseca and from one site that is affected by heron colonies (Garcera) in the TDNP showed higher concentrations of organic matter, total organic carbon, total nitrogen, total phosphorus, Al, Co, Cu, Cr, Fe, Ni and Zn than the rest of the sampling sites. Significant correlations between these variables were found, probably suggesting that they have a common organic source. The highest δ15N values in sediments of the TDNP were registered in Guadiana, a site where there is no impact from colonies; these values might therefore be due to anthropogenic activities. Metal and metalloid content in sediments was lower than the regional reference values in soils, except for Se in the TDNP, and Zn and Cu in Navaseca. High Se level in TDNP sediment may be caused by seleniferous soils located upstream. Results showed a low impact of bird droppings compared to other sources of nutrients in the annual input in the TDNP.

Water resources sustainability model for wetland conservation based on anonymous expert elicitation

Wetlands play a key role in preserving biodiversity and preventing climate change. Their conservation poses an important and pressing challenge. In the Mediterranean region, one of the key threats to wetland survival is the lack of water due to competition for resources. The selection of the most sustainable water resources for wetland conservation is a complex elicitation problem. A novel Water Resources Sustainability Model (WRSM) focused on water quality has been developed to support the decision-making. This collaborative elicitation model is based on the analytical hierarchy process and uses the reference environmental status of the wetland. The model can be used to discriminate which water resources are more sustainable for the conservation of the wetland. The WRSM has been applied successfully to Las Tablas de Daimiel National Park. The framework enables establishing priorities when analyzing in terms of water quality any surface, recycled or underground water resources.

Metals and metalloids in freshwater fish from the floodplain of Tablas de Daimiel National Park, Spain

The Tablas de Daimiel National Park (TDNP) is a floodplain ecosystem in central Spain with a potential risk of heavy metal and metalloid pollution. The objective of this study was to know the accumulation of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), and selenium (Se) in muscle of six species of freshwater fish from the floodplain of TDNP. We obtained muscle samples of Cyprinus carpio (n = 89); Squalius pyrenaicus (n = 16); Ameiurus melas (n = 9); Lepomis gibbosus (n = 8); Micropterus salmoides (n = 6) and Carassius auratus (n = 5). A. melas, which is a predatory species, had significantly higher Hg concentrations than omnivorous or herbivorous species (i.e. C. carpio). On the contrary, A. melas showed lower concentrations of As, Pb and Se than omnivorous species (i.e. S. pyrenaicus and L. gibbosus ). The concentration of Hg was positively associated with fish size in C. carpio and A. melas. Some individuals of C. carpio (5.7%) and S. pyrenaicus (12.5%) showed Pb muscle concentrations above the maximum residue levels established by the European legislation for human consumers. The observed muscle Se concentrations can be associated with adverse effects on fish such as blood changes, reduced growth, mortality of juveniles and reproductive failure. The accumulation of Se in this floodplain located in a seleniferous area and the contamination produced by spent Pb shot pellets used for hunting in the past are discussed as potential sources of the elevated levels of these two elements in fish from this floodplain wetland.

Psychrobacillus vulpis sp. nov., a new species isolated from faeces of a red fox in Spain.

A facultative anaerobic, chemoheterotrophic, endospore-forming, Gram-stain-positive rod, designated as strain Z8T, was isolated from red fox (Vulpes vulpes) faeces sampled at Tablas de Daimiel National Park, Ciudad Real, Spain. Strain Z8T grew at 0-37 °C (optimum, 28 °C), in the presence of 0-5.5 % (w/v) NaCl (2.5 %, w/v) and at pH 6-10 (pH 7). The strain was motile and positive for catalase, oxidase, H2S and siderophore production, acid and alkaline phosphatases, and N-acetylglucosamine, adipic acid and malate assimilation. It hydrolysed starch, DNA, l-tyrosine, Tween 20, Tween 80 and lecithovitellin. Phylogenetic analysis of the 16S rRNA gene sequence indicated that strain Z8T is a member of the genus Psychrobacillus, showing high sequence similarity to Psychrobacillus lasiicapitis NEAU-3TGS17T (99.2 %) and Psychrobacillus soli NHI-2TT (99.1 %), and around 98 % to other known species of the genus Psychrobacillus. Digital DNA-DNA hybridization and average nucleotide identity values were lower than 24 and 79 %, respectively, with the most related species. In silico G+C content was 35.9 mol%. The major cellular fatty acids of strain Z8T were iso-C14 : 0, iso-C15 : 0 and anteiso-C15 : 0. The novel strain contained diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol as predominant polar lipids, and the main respiratory isoprenoid quinone was MK-8. Based on the 16S rRNA phylogenetic analysis, together with MLSA (recA, rpoB and gyrB), phylogenomic, chemotaxonomic and phenotypic results, we demonstrate that strain Z8T represents a novel species of the genus Psychrobacillus, for which the name Psychrobacillus vulpis sp. nov., is proposed. The type strain is Z8T (=CECT 9721T=LMG 31001T).

Lessons learnt from semi-arid wetland degradation. Las Tablas de Daimiel National Park

The Tablas de Daimiel National Park wetland developed in an area characterized by the cyclic nature of droughts, excessive aquifer exploitation and an evident aridification trend driven by climate change. The park and its surroundings have been exploited since prehistoric times and they are currently deeply anthropized to the point that both the physical survival of the wetland as well as its ecological function entirely depend on human action. A severe drought between 2006 and 2009 together with the drawdown of the water table caused the dry out of the system, reed overgrowth, disappearance of cut-sedge and sub-aquatic Chara spp. meadows and a smouldering peat fire. During this same period surface water, soil and groundwater were sampled for physical, hydrological and hydrochemical characterization. Upon drainage, the system functions as an artificial recharge system and becomes eutrophic showing large nutrient and salt content in soils and water. High water transmissivity capacities in the unsaturated zone and anthropic park management (soil compacted by heavy machinery, recirculation of low quality groundwater, reed reaping, water transfers, etc.) condition groundwater pollution. Increased knowledge of the physical-environment has allowed us to build a conceptual model of the surface water – groundwater interactions and to develop management tools to support the park management during a system dry out. Amongst these actions, we propose an unsaturated flow model for soil moisture simulation than can be used to predict critical soil water content for reed overgrowth or peat combustion risk.

Current Status of Las Tablas de Daimiel National Park Wetland and Actions Required for Conservation

Wetlands are complex ecosystems that play multiple roles. ‘Las Tablas de Daimiel National Park’ (TDNP) undoubtedly plays a role in several ecosystem services and provides a connection between nature, farmers, scientists, residents, and other stakeholders. The state of degradation and/or vulnerability of this ecosystem (with a series of socio-economic implications) have led the publication of numerous articles. The work reported here provides a description of the growing importance of this wetland within the rural landscapes of La Mancha and emphasizes its state of degradation, mainly since pedological point of view. In this way, particular attention is required to assure the conservation of the Tablas of Daimiel Wetland; thus, several measures are proposed to improve the conservation of this area as to control and prohibit any dumping of any type of waste in the park or in its vicinity.

La Monarquía Hispánica y el control de los recursos hídricos: hacia la desecación de Las Tablas de Daimiel de 1751

El control de los recursos hídricos fue un objetivo fundamental para la Monarquía Hispánica en La Mancha durante la Edad Moderna. La desecación en 1751 de la superficie encharcada que forma el actual Parque Nacional de Las Tablas de Daimiel, promovida por Fernando VI, es un buen ejemplo de dicho control. Este artículo analiza los principales factores que confluyeron en aquella decisión que supuso la primera gran obra hidráulica de la monarquía borbónica en la cuenca del Guadiana. Para ello se ha estudiado, principalmente, la evolución de los molinos harineros del entorno de Las Tablas de Daimiel durante la Edad Moderna, los conflictos ocasionados por el control del caudal y la climatología de la zona durante la época estudiada. La presión de los molineros sobre el río y el aumento de la aridez provocaron una creciente conflictividad que la monarquía intentó resolver con la desecación. Sin embargo, el principal objetivo fue satisfacer los intereses recaudatorios de la monarquía y los de una serie de ganaderos de la zona vinculados al rey.

Wax esters of uropygial gland secretion as biomarkers of endocrine disruption in birds exposed to treated sewage water

The chemical composition of the uropygial gland secretion of birds shows seasonal, sex and age-related variations following sex hormones fluctuations. We explore the use of the composition of the uropygial gland secretion as a non-invasive biomarker of endocrine disruption in 137 common moorhens (Gallinula chloropus) from Navaseca Pond, which receives the effluent of a wastewater treatment plant, and from the more pristine Tablas de Daimiel National Park in Spain. Wax ester and fatty acid compositions were measured by means gas chromatography – mass spectrometry (GC-MS) in the uropygial gland secretion of moorhens from both wetlands. Organochlorine compounds (p,p’-DDE and PCBs) were measured in blood and uropygial gland secretion of moorhens as indicators of anthropogenic pollutants, and this information was interpreted together with previous results of the accumulation of metals and metalloids in blood and feathers of these moorhens and a wide range of endocrine disrupting chemicals (EDCs) measured in water from both study sites. PCBs and p,p'-DDE were found in 32% of the blood and 51% of uropygial gland secretion samples, being at highest levels in Navaseca. Wax composition was dominated by monoesters of 35–38 carbons and displayed a clear seasonal variation, in which long-chain wax esters were more abundant in spring-summer than in autumn-winter. This seasonal change was less evident in birds from Navaseca, where the presence of shorter wax esters was associated with the higher concentration of PCBs in uropygial gland secretion. The observed effect may not be associated with this specific type of pollutants because moorhens in Navaseca are also exposed to a wide diversity endocrine disruptors as shown in a previous study. Uropygial gland secretion can be a useful non-invasive sample for integrating chemical monitoring of pollutants and their effects as endocrine disruptors in birds.

Effects of flooding regime and meteorological variability on the removal efficiency of treatment wetlands under a Mediterranean climate

The modeling of free-water surface constructed wetlands (FWS-CWs) provides an improved understanding of their processes and constitutes a useful tool for the design and management of these systems. In this work, a dynamic simulation model for FWS-CWs was developed and used to simulate the operation of a FWS-CW proposed for improving the treatment of sewage effluents entering the Tablas de Daimiel National Park in central Spain. The process-based model simulates carbon, nitrogen and phosphorus dynamics, including key hydrological processes for wetlands under a fluctuating Mediterranean semiarid climate. The model allows for the simulation of the operation of FWS-CWs with variable flooding regimes, relating the surface water level to the flooded area and the water outflow. Simulations of the proposed FWS-CW under different water management schemes and scenarios were run, and the consequences of those management strategies on the treatment efficiency were analyzed. Under the Mediterranean climate and geology of the study area, namely, high water losses through evapotranspiration and infiltration, the decrease in nutrient concentrations was higher when the flooded area was reduced in summer than when a constant flooded area was maintained. Moreover, the meteorological variability introduced in different scenarios produced different results in terms of water outflow, but differences in terms of nutrient concentrations were not significant. The ability of the model to simulate different hydrological scenarios and their consequences on water quality makes it a useful decision-support tool.

Long‐term effects of aquifer overdraft and recovery on groundwater quality in a Ramsar wetland: Las Tablas de Daimiel National Park, Spain

AbstractLas Tablas de Daimiel National Park is one of Spain's most representative groundwater‐dependent ecosystems. Under natural conditions, water inflows combined brackish surface water from River Gigüela with freshwater inputs from River Guadiana and the underlying aquifer. Since the mid‐1970s, aquifer overexploitation caused the desiccation of the wetlands and neighbouring springs. The National Park remained in precarious hydrological conditions for three decades, with the only exception of rapid floods due to extreme rainfall events and sporadic water transfers from other basins. In the late 2000s, a decrease in groundwater abstraction and an extraordinarily wet period reversed the trend. The aquifer experienced an unexpected recovery of groundwater levels (over 20 m in some areas), thus restoring groundwater discharge to springs and wetlands. The complex historical evolution of the water balance in this site has resulted in substantial changes in surface and groundwater quality. This becomes evident when comparing the pre‐1980 groundwater quality and the hydrochemical status in the wetland in two different periods, under “dry” and “wet” conditions. Although the system is close to full recovery from the groundwater‐level viewpoint, bouncing back in the major hydrochemical constituents has not yet been obtained. These still appear to evolve in response to the previous overexploitation state. Moreover, in some sectors, there are groundwater‐dependent ecosystems that remain different to those found in preoverexploitation times. The experience of Las Tablas de Damiel provides an observatory of long‐term changes in wetland water quality, demonstrating that the effects of aquifer overexploitation on aquatic ecosystems are more than a mere alteration of the water balance and that groundwater quality is the key to aquifer and aquatic ecosystem sustainability.

Metals and metalloids in blood and feathers of common moorhens (Gallinula chloropus) from wetlands that receive treated wastewater

We addressed the hypothesis that birds in eutrophic wetlands receiving wastewater treatment plant (WWTP) effluents are exposed to high levels of metals and metalloids and this may drive an ecological trap in some species attracted to these highly productive ecosystems. Levels of metals and metalloids were determined in sediment and in blood and feathers of common moorhens (Gallinula chloropus) from two wetlands in Central Spain: Navaseca Pond, which receives directly the effluent of a WWTP; and Tablas de Daimiel National Park, which is a floodplain less affected by urban discharges. Sediment concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb were higher in Navaseca Pond than in Tablas de Daimiel; only Se was higher in Tablas de Daimiel than in Navaseca. Blood levels of Hg and Se were higher in moorhens from Tablas de Daimiel than those from Navaseca. In the case of Hg these levels were below the threshold of adverse effect, but Se levels in 24% of moorhens from Tablas de Daimiel were above the threshold value associated with Se toxicity in birds (1000 ng/mL). In feathers, Hg, Se, Mn, Cu and As levels were higher in Tablas de Daimiel than in Navaseca. Body condition of moorhens was negatively associated with blood Se levels in the moorhens from Tablas de Daimiel. We can reject the hypothesis of a higher accumulation of metals and metalloids in birds associated with the WWTP effluent, but Se levels may need further research considering the nature of the floodplain of Tablas de Daimiel National Park.

Species distribution modelling through Bayesian hierarchical approach

Usually in Ecology, the availability and quality of the data is not as good as we would like. For some species, the typical environmental study focuses on presence/absence data, and particularly with small animals as amphibians and reptiles, the number of presences can be rather small. The aim of this study is to develop a spatial model for studying animal data with a low level of presences; we specify a Gaussian Markov Random Field for modelling the spatial component and evaluate the inclusion of environmental covariates. To assess the model suitability, we use Watanabe-Akaike information criteria (WAIC) and the conditional predictive ordinate (CPO). We apply this framework to model each species of amphibian and reptiles present in the Las Tablas de Daimiel National Park (Spain).

Breeding in a Dry Wetland. Demographic Response to Drought in the Common Reed-Warbler Acrocephalus scirpaceus

Mediterranean wetlands show remarkable seasonal and annual variations in their hydroperiod, i.e. the period during which they are inundated. Climate change-induced hydroperiod reductions have been shown to affect marshland birds but more studies are needed to understand this process in Mediterranean wetlands. The present study shows the demographic response of the Common Reed-warbler Acrocephalus scirpaceus to an unusual and prolonged drought in the Tablas de Daimiel National Park wetland (central Spain). We used data from two constant effort mistnetting stations (2005–2013), and spatially explicit capture-recapture Jolly-Seber models. The Reed-warblers continued reproducing in a dry environment for three years after the start of a dry phase, despite progressive declines in productivity, and ultimately stopped nesting in the fourth year. After the recovery of water levels in subsequent years, the population required another four years to recover a size and productivity similar to those preceding the drought. This situation may be common in the near future given ongoing alterations of the hydroperiod in Mediterranean wetlands as a consequence of climate change and groundwater overexploitation. We also show that spatially explicit capturerecapture models allow the detection of changes in the populations of small passerines, and are an accurate approach to estimating their densities. —Jimenez, J., Hernandez, J.M., Feliu, J., Carrasco, M. & Moreno-Opo, R. (2018). Breeding in a dry wetland. Demographic response to drought in the Common Reed-warbler Acrocephalus scirpaceus. Ardeola, 65: 247–259.

Primary Producers and Anthropic Signs Related to the Flood Plain Soils of the Tablas de Daimiel Wetland

In the Tablas de Daimiel National Park (TDNP) wetlands, a semi-arid wetland system in Spain that is of international importance, it is believed that pollutants from a variety of sources accumulate. In the study reported here, we evaluated soils from the flooded part of this wetland in an effort to establish relationships between the abundance/structure of microbial communities (mainly cyanobacteria) and certain soil properties (redox potential, dissolved oxygen, organic matter, soil reaction, electrical conductivity, calcium carbonate, total nitrogen, soluble phosphorus and total phosphorus). This objective was achieved by establishing one transect from the entrance to exit of the flood plain, including sampling from potentially polluted sites. Substantial variations between sampling sites were found in soil in terms of salinity, dissolved oxygen (DO), organic matter (OM), total phosphorus (TP) and nitrogen (TN). The presence of primary producers was more evident in contaminated samples. In addition to calcium, high levels of oxidizable organic matter, traces of dissolved oxygen, and considerable amounts of nitrate and phosphates probably stimulated the growth of cyanobacteria, these latter characteristics can be explained as being due to the influence of wastewaters from urban, industrial and agricultural activities that run off directly into this unique wetland. In the future it will be necessary to understand the synergic effects of other soil properties.