The plants of Doñana National Park’s Marisma (Spain): a key element for conservation of an emblematic european wetland

El Parque Nacional de Doñana (SW de España), es el espacio natural protegido más emblemático del Estado Español. Incluye uno de los humedales más extensos de Europa Occidental, la marisma, que también resulta ser el mayor santuario para las aves migratorias del continente europeo. El soporte trófico y estructural de este humedal lo constituyen las comunidades vegetales que allí se desarrollan. Sin embargo, a pesar de su importancia, el nivel de conocimiento sobre los vegetales de la marisma y sus comunidades es muy escaso. Por ello, se realizó un análisis florístico de la marisma, donde se tomaron en cuenta aquellos trabajos que corresponden a citas de plantas recolectadas en la marisma y depositadas en herbarios, así como observaciones debidamente contrastadas, contemplando además de las plantas vasculares, los briófitos y las macroalgas. El resultado proporcionó 247 taxones diferentes, que corresponden a 61 familias, y cuyo patrón se aparta del que presentan los hábitats mediterráneos típicos. También, a partir de los datos del catálogo, se muestra como en dicho hábitat son escasos los endemismos y predominan las especies con grandes áreas de distribución. Se describen las principales comunidades vegetales de la marisma y cómo se organizan en función del tiempo de inundación de los suelos y de la concentración de sales que estos presentan. Asimismo, se identifican diversos problemas que afectan a la conservación de los ecosistemas del Parque Nacional de Doñana, como la disminución del volumen de agua de la marisma, el deterioro de la calidad de sus aguas y la aparición de especies exóticas invasoras.Doñana National Park (SW Spain) is the flagship of the Spanish State Protected Natural Areas. It includes one of the largest wetlands in Western Europe, the marsh, which also happens to be the largest sanctuary for migratory birds on the continent. The trophic and structural support for this wetland depends on the plant communities developed there. However, despite its importance, the level of knowledge about the marsh´s plants and their communities is limited. Here we present a Floristic Catalogue from the marsh encompassing 247 different taxa within 61 families. The biogeographic pattern of the marsh is atypical compared to other Mediterranean habitat. We find limited endemism and a predominance of species with large geographic ranges. We also describe the main plant communities from the marsh, which are organized according to time of flooding and soil salt concentration. We use this information to identify several problems that affect the conservation of ecosystems from Doñana National Park

Clonal reproduction of Azolla filiculoides Lam.: implications for invasiveness

Clonal reproduction of Azolla filiculoides Lam., an aquatic floating fern, native from the American subtropics and a recent invader of Mediterranean wetlands, was assessed experimentally. Shoot fragmentation of the species was quantified under suitable room conditions for optimum growth. Azolla fililculoides showed high longevity, a low mortality percentage and a high potential for clonal reproduction (biomass obtained by shoot fragmentation from only one individual was multiplied by 100). This last attribute changed over time: first generations developed a high number of propagules, a number which decreased progressively in later generations until the end of the experiment. The results of this experiment will be useful for understanding Azolla’s success within invaded habitats

The invasion of Doñana National Park (SW Spain) by the mosquito fern (Azolla filiculoides Lam)

In 2001, Azolla filiculoides Lam., a floating pteridophyte native to the New World, was found in Doñana National Park (SW Spain), an European protected area well known for its high value from a conservation point of view and for its ecological vulnerability. Until that time, there had been no exotic aquatic macrophyte observations in the National Park. Since then, surfaces covered by Azolla filiculoides have increased explosively forming thick floating mats which eliminate submersed plants, and seriously threaten the aquatic ecosystems in this important protected area.En 2001, Azolla filiculoides Lam., una pteridófita acuática nativa del Nuevo Mundo, fue encontrada en el Parque Nacional de Doñana (SW España), un espacio protegido europeo bien conocido por su alto valor desde el punto de vista de la conservación y por su vulnerabilidad ecológica. Hasta ese momento, no se había observado ningún macrófito acuático exótico en el Parque Nacional; desde entonces, las superficies cubiertas por Azolla filiculoides se han incrementado de manera explosiva originando gruesas capas flotantes que eliminan las plantas acuáticas sumergidas y amenazan gravemente los ecosistemas acuáticos de este importante espacio protegido

Consideraciones sobre la génesis de una turbera meridional: la Laguna de las Madres y otras lagunas cercanas (Huelva, SW España)

En la provincia de Huelva (SO España) se encuentra una de las más importantes turberas del sur de la Península Ibérica: La Laguna de las Madres, hábitat extremadamente escaso en estas regiones meridionales. En este trabajo se muestran los resultados preliminares de un importante estudio sobre la Laguna de las Madres, actualmente en desarrollo. A partir de datos procedentes de la reconstrucción de las cuencas, del análisis de la cartografía y documentación histórica, se aportan ideas sobre la evolución y génesis de este humedal que sirve de refugio a organismos de gran singularidad con áreas de distribución reducidas o muy fragmentadas

The influence of geomorphology on the composition of aquatic flora and fauna withim a temporary pond network

Geomorphological and hydrological features can provide a sound basis for global wetland classification. Temporary ponds located on the sandy area of Doñana can be classified into five different geomorphological areas. We hypothesised that these ponds would differ in soil characteristics, which may also explain differences in the composition of their macroinvertebrate, amphibian, and aquatic plant species assemblages. The study ponds were significantly segregated into southern and northern geomorphological areas based on the depth to the water table. The results of the multivariate ordination of soil variables were consistent with a north-south segregation, which was explained by the carbonate and other main ion concentrations in the pond basins. The ponds located in ecotones (marsh-sand and stable-mobile dunes) were particularly rich in amphibians and macroinvertebrates. This result may be explained because the ponds with the longest permanence of water were located in these areas, which represented the only flooded ponds during droughts. In addition, they also contained a high number of temporary ponds, thus favouring connectivity and environmental heterogeneity in these areas

Las lagunas temporales del Parque Nacional de Doñana: un sistema de hábitats naturales para la conservación de la flora y fauna acuáticas.

Mediterranean temporary ponds are a priority habitat under the European Union Habitats Directive, but those of natural origin are scarce, as many of them have been destroyed or transformed into permanent waters. The aim of this study is to highlight the conservation value of the system of temporary ponds in Do˜nana National Park, where more than 3000 water bodies may be lled during wet years. They are located on soils of aeolian origin where water persistence is favoured by the presence of an argilic semi permeable horizon and by a relic clay-rich sandy layer. Temporary ponds can be classi ed across a wide hydroperiod gradient. Most ponds ll with autumnal or winter rains and persist up to late spring or summer, and only a few may persist through summer. Eight of the 11 amphibian species of this area require temporary ponds for breeding. More than 124 taxa of macroinvertebrates have been recorded, coleopterans (56 taxa) and heteropterans (19 taxa) being the richest taxonomic groups. Several zooplankton species are endemic to this kind of habitats, such as the copepod Dussartius baeticus and the rotifer Lecane donyanensis. Regarding vegetation, at least 55 hydrophytes species were identi ed in the ponds sampled, and also some species endemic to SW Iberian Peninsula (Callitriche regis-jubae, Scorzonera stulosa, Callitriche lusitanica) and others are in relic situation (Hydrocharis morsus-ranae, Thorella verticillato-inundata, Lemna trisulca). The conservation value of these ponds is highlighted by the large variety of protected and/or rare species of ora and fauna, which are favoured by a high pond abundance and connectivity

Flora y vegetación de la marisma de Doñana en el marco del proyecto de restauración ecológica Doñana 2005

Doñana 2005 is an ambitious ecological restoration project that is developed in the wetlands of the Doñana protected space (SW Spain). The objective of this article is to present the preliminary results of the Flora and Vegetation Team linked to the project. Floristic spectrum and phytogeographical elements from the flora of the study area are shown. Furthermore, data corresponding to the evolution of the land cover vegetation of the studied zones is offered.Doñana 2005 es un ambicioso proyecto de restauración ecológica que se desarrolla en el los humedales del espacio protegido de Doñana (SW España). El objetivo de este artículo es dar a conocer los resultados preliminares del Equipo de Flora y Vegetación vinculado a dicho proyecto. Se muestran el espectro florístico y los elementos fitogeográficos de la flora del área de estudio. Asimismo se ofrecen datos correspondientes a la evolución de la cubierta vegetal de las zonas estudiadas

Terrestrial Morphotypes of Aquatic Plants Display Improved Seed Germination to Deal with Dry or Low-Rainfall Periods

In temporary ponds, seed germination largely determines how well aquatic plant assemblages recover after dry periods. Some aquatic plants have terrestrial morphotypes that can produce seeds even in dry years. Here, we performed an experiment to compare germination patterns for seeds produced by aquatic and terrestrial morphotypes of Ranunculus peltatus subsp. saniculifolius over the course of five inundation events. During the first inundation event, percent germination was higher for terrestrial morphotype seeds (36.1%) than for aquatic morphotype seeds (6.1%). Seed germination peaked for both groups during the second inundation event (terrestrial morphotype: 47%; aquatic morphotype: 34%). Even after all five events, some viable seeds had not yet germinated (terrestrial morphotype: 0.6%; aquatic morphotype: 5%). We also compared germination patterns for the two morphotypes in Callitriche brutia: the percent germination was higher for terrestrial morphotype seeds (79.5%) than for aquatic morphotype seeds (41.9%). Both aquatic plant species use two complementary strategies to ensure population persistence despite the unpredictable conditions of temporary ponds. First, plants can produce seeds with different dormancy periods that germinate during different inundation periods. Second, plants can produce terrestrial morphotypes, which generate more seeds during dry periods, allowing for re-establishment when conditions are once again favorable.Ministerio de Ciencia e Innovación PID2019-104343RB-10

Combining multicriteria decision analysis and GIS to assess vulnerability within a protected area: An objective methodology for managing complex and fragile systems

Characterizing zone fragility is a significant challenge when managing natural areas, but it must be prioritized in conservation efforts. The most commonly employed methodology is to rely on criteria established by experts, which can introduce subjectivity. However, more objective approaches should be used when developing conservation plans. This study follows one methodology focusing on classifying zone vulnerability within a protected natural area, taking as a study case a temporal pond network located in SW Spain; threatened aquatic plants were used as a bioindicators. Spatial data were analyzed using geographic information systems (GIS), and potentially vulnerable zones were identified using multicriteria decision analysis (MCDA) and, more specifically, the weighted overlay method. Criteria weights were determined by variables contribution obtained through species distribution models (SDM), via the maximum entropy algorithm (MaxEnt). The purpose was to avoid artificial bias in decision-making. The analysis indicated that 42.04% of the study area was highly vulnerable. In contrast, only the 14.34% of the study area was at very low risk, meaning it can help maintain pond network biodiversity. These results indicate that potentially vulnerable and crucial zones can be identified using GIS, facilitating the establishment of conservation priorities in a complex system. This methodology could be useful for prioritizing and implementing management and conservation efforts focused on unique species and habitats in protected natural areas.Ministerio de Agricultura, Alimentación y Medio Ambiente 158/2010CSIC ICTS-RB