Experimental and full–scale pilot plant constructed wetlands for municipal wastewaters treatment

p. 43-52El (HMAE®) fue desarrollado originalmente en Bélgica mediante la aplicación de los valores ecológicos en las plantas hidrófilas inundadas y contaminadas. El sistema consistía en un estanque de estabilización (etapa I) seguido de un ecosistema semi-acuático plantado con helófitos (fase II) y por un ecosistema terrestre (fase III) donde se plantan especies leñosas. Un área de tratamiento neto del sistema experimental HMAE® de 9.4m2 por un habitante equivalente (ei) mostró un alto rendimiento promedio de los SS (66,5%); DQO (89%); DBO5 (87,5%) y bacterias fecales (99,997%). La disminución de la área de tratamiento de 2.8m2 / e.i. mostró un alto rendimiento promedio de SS (75%); DQO (80%); DBO5 (82%) y bacterias fecales (99,9%). Un sistema HMAE® fue construido en Bustillo de Cea (León, al noroeste de España) y se estudió su eficiencia de remoción. La materia orgánica, nutrientes y bacterias fecales se analizaron quincenal. Todo el sistema demostró eficiencias de remoción en la puesta en marcha tan alta como 98% de sólidos, 95% de DBO5 y hasta 99,99% para las bacterias fecalesS

Bacterial community composition and diversity uncovered in experimental sludge treatment reed bed systems with different swine slurry hydraulic loadings

P. 175-184Nowadays swine slurry management is a very important environmental issue. Sludge treatment reed bed systems are sludge treatment systems based on constructed wetlands. The present study characterizes via 16S rRNA gene high-throughput the bacterial communities contained in untreated swine slurry and treated swine slurry by means of mesocosm-scale sludge treatment reed beds receiving different slurry loadings. The bacterial community composition varied between the treated and untreated slurry, with a notable slurry loading influence also observed. Richness, diversity and ordination measurements of the studied communities evidenced profound differences between the untreated and treated swine slurry bacterial communities; and only slight differences among the treated swine slurry communities. Interestingly, the slurry loading allowed to define two groups: mesocosm communities residing in the highest hydraulic slurry loadings and other mesocosm communities. The pH value emerged as an important community composition, diversity and ordination predictor. The functional bacterial community composition was predicted through the in silico approach. Results confirmed that the main nitrogen cycle metabolic pathways were present in the mesocosm communities with ammonification and assimilatory nitrate reduction as the most commonly detected nitrogen pathways in treated swine slurry.S

A new index of resilience applicable to external pulse-disturbances that considers the recovery of communities in the short term

.Resilience is a key concept in the study of the recovery of ecosystems affected by disturbances. Currently, there are numerous indices to measure resilience, but many of them do not show the accuracy of the resilience value or the behaviour of ecological parameters in the face of disturbances. New approaches and technologies enable large amounts of information to be obtained, facilitating the proposal of new resilience indices that work consistently and intuitively for a wide variety of ecological response variables under different scenarios after pulse-disturbances. In this study, we propose and verify a new resilience index, comparing its performance with others previously published. We validated the performance of the new index using real data based on field measurements of changes in soil bacterial OTUs diversity and abundance after a wildfire. The new resilience index provided an automatic and robust functional classification of the behaviour of ecosystems after disturbances, supported by a bootstrap analysis. We identified 5 scenarios of ecosystem resilience performance according to their behaviour after a pulse-disturbance: resilient, non-resilient, recovering, rebound, and continuing.S

Resistance of soil bacterial communities from montane heathland ecosystems in the Cantabrian mountains (NW Spain) to a gradient of experimental nitrogen deposition

[EN] Elevated atmospheric nitrogen (N) deposition on terrestrial ecosystems has become one of the most important drivers of microbial diversity loss on a global scale, and has been reported to alter the soil function of nutrient-poor, montane Calluna vulgaris heathlands in the context of global change. In this work we analyze for the first time the shifts of bacterial communities in response to experimental addition of N in Calluna heathlands as a simulation of atmospheric deposition. Specifically, we evaluated the effects of five N addition treatments (0, 10, 20, and 50 kg N ha−1 yr−1 for 3-years; and 56 kg N ha−1 yr−1 for 10-years) on the resistance of soil bacterial communities as determined by changes in their composition and alpha and beta diversities. The study was conducted in montane Calluna heathlands at different development stages (young and mature phases) in the southern side of the Cantabrian Mountains (NW Spain). Our results evidenced a substantial increase of long-term (10-years) N inputs on soil extractable N-NH4+, particularly in young Calluna stands. The alpha diversity of soil bacterial communities in mature Calluna stands did not show a significant response to experimental N addition, whereas it was significantly higher under long-term chronic N addition (56 kg N ha−1 yr−1 for 10-years) in young Calluna stands. These bacterial community shifts are mainly attributable to a decrease in the dominance of Acidobacteria phylum, the most representative in montane Calluna ecosystems, in favor of copiotrophic taxa such as Actinobacteria or Proteobacteria phyla, favored under increased N availability. Future research should investigate what specific ecosystem functions performed by soil bacterial communities may be sensitive to increased nitrogen depositions, which may have substantial implications for the understanding of montane Calluna ecosystems' stability.SINext-Generation Funds of the European Union (EU) in the framework of the FIREMAP project (TED2021-130925B-I00)Regional Government of Castile and León in the framework of the IA-FIREXTCyL project (LE081P23)Portuguese Foundation for Science and Technology in the frame of project UIDB/04033/2020Spanish Ministry of Universities (FPU21/00309

Greenhouse effect gases emission implications on sustainability of the Campus of Vegazana, University of León

[ES] En este trabajo se presentan los resultados del estudio de emisiones de CO2, uno de los gases más importantes de efecto invernadero, debido a la actividad desarrollada en el Campus de Vegazana de la Universidad de León, para el año 2006. El estudio se enmarca en un proyecto más amplio de cálculo del indicador Huella Ecológica (HE), desarrollado para conocer en qué medida se alcanzan los objetivos de sostenibilidad establecidos para el Campus, así como para el desarrollo de propuestas encaminadas a la reducción de las emisiones de CO2. Los resultados obtenidos reflejan como el área de superficie biológicamente productiva necesaria para absorber las emisiones del Campus constituyen cerca del 99% del área total de HE. La mayor parte de estas emisiones proceden del gasto energético para electricidad (38%) y uso térmico (24%), seguido del transporte (19%) y la construcción del propio complejo universitario (16%), el cual hace referencia únicamente al año 2006, considerando una vida útil de 27 años para los edificios e instalaciones del Campus, inaugurado en 1979. Una vez analizadas cualitativa y cuantitativamente las emisiones producidas, se ha buscado conocer el total de superficie forestal necesaria para absorber dichas emisiones, considerando los datos del Tercer Inventario Forestal Nacional (2003) sobre cobertura de las masas forestales para el territorio nacional, y los aportados por Bravo (2007) en relación a las tasas de fijación del gas por parte de éstas. Como conclusión, puede estimarse que del total de la superficie forestal de la provincia de León, un 0.46% es necesaria como depósito y sumidero del CO2 emitido por el Campus de Vegazana (8.470.168 toneladas). Esta estimación se ha realizado considerando que las masas forestales son las únicas depositarias de CO2, tarea compartida en la naturaleza, no obstante, con el suelo, el agua y los cultivos[EN] In this work, we present the results obtained about the CO2 emissions, one of the most important greenhouse gases, due to the normal activity developed in the Campus of Vegazana of the University of León for the year 2006. This study is all part of a wider project for evaluating the Fingerprint ecological indicator (HE), initially developed for assessing if the sustainability objectives established by the University policies for the Campus of Vegazana have been achieved, as well as the development of proposals and ideas directed towards the reduction of the emissions of CO2. Results obtained showed that the biologically productive area necessary for absorbing all emissions are close to the 99% of the total value of HE. The majority of these emissions come from the energy consumed for producing electricity (38%) and heating (24%), followed by the transport (19%) and the constructions of the buildings and infrastructures of the University (16%), which related just for the year 2006, considering a living period of 27 years as it was inaugurated in 1979. Once analyzed qualitatively and quantitatively the emissions produced, it was developed a method for estimating the total area covered necessary for absorbing them by considering data available from the Third National Forestry Inventory of Spain (2003), related with the forest cover of the territory, and data provided by Bravo (2007), about the absorption rate of the tree species. As a conclusion, we estimated that form the total area covered by forests of the Province of León, a 0.46% is necessary as sink of the CO2 produced in the Campus of Vegazana (8.470.168 ton). This assessment has been achieved considering that forests are the only warehouse of CO2, when actually soil, water and crops are in natureN

Mulching treatments favour the recovery of ecosystem multifunctionality after a large wildfire in Northwest Spain

[EN] Wildfires are a widespread phenomenon in forests across the Mediterranean Basin but have increased in risk and severity in recent decades. Post-fire treatments are measures that help recover burned vegetation and their functionality but to what extent they also help recover soil functionality is currently unknown. The main objective of this study was to assess the effect of post-fire treatments on ecosystem multifunctionality after a large wildfire in the Cabrera mountain range in 2017 (NW Spain) where close to 10000 Ha of forest were burnt. At the end of 2017 and during 2018, the administration applied different post-fire treatments in high fire severity affected areas: i) straw mulching, ii) woody debris and iii) subsoiling and iv) mechanical hole afforestation. In each treatment, we established ten 2 x 2 m plots and ten adjacent untreated burned plots and collected a composite soil sample from each plot four years after the fire (2021). We calculated regulating services as the standardized mean of total soil organic C (climate regulation), soil water repellence (water regulation) and soil aggregation (soil protection). Supporting services were measured as the standardized mean of mineral N-NH4+ and N-NO3- and available P (soil fertility), β-glucosidase, urease and acid phosphatase (nutrient cycling) and microbial biomass (soil quality). Ecosystem multifunctionality was measured as the standardized mean of all functions measured. Application of straw mulch and woody debris increased regulating ecosystem services in relation to burned control plots. Afforestation with holes had no impact but subsoiling decreased regulating ecosystem services in relation to burned control plots. Post-fire treatments did not have any effect on supporting services. Straw mulch, Woody debris and afforestation with holes improved ecosystem multifunctionality when compared with subsoiling methods. These results show that post-fire stabilisation treatments, in particular straw mulching have a significant positive impact on regulating services and are effective measures in restoring the ecosystem multifunctionality, helping develop effective management based-decisions for the recovery of ecosystem services and functioning after large wildfiresThis research was financially supported by the Spanish Ministry of Economy and Competitiveness in the framework of the FIRESEVES (AGL2017-86075-C2-1-R) project, and by the Regional Government of Castilla and León in the framework of the WUIFIRECYL (LE005P20) projec

Evaluación de la resiliencia forestal al fuego mediante la inversión de modelos de transferencia radiativa a partir de imágenes de satélite

[ES] El objetivo de este estudio fue evaluar la resiliencia ingenieril a corto plazo de diversas comunidades de matorral en función de su estrategia regenerativa y la severidad del fuego, dentro del perímetro de un mega-incendio ocurrido en verano de 2017 en el noroeste de la Península Ibérica. Se dispuso de una serie temporal de imágenes de satélite Sentinel-2 para las que se computó la fracción de cubierta vegetal (FVC) para cada pixel mediante la inversión híbrida del modelo de transferencia radiativa (RTM) PROSAIL-D utilizando el algoritmo random forest. Se obtuvo un elevado ajuste para toda la serie temporal (R2 > 0,75), a partir de la validación con datos de campo. Mediante un muestreo de FVC de puntos aleatorios estratificados por tipo de estrategia regenerativa y nivel de severidad del fuego, se determinó la resiliencia de las comunidades de matorral en términos de recuperación de la cobertura utilizando un índice de resiliencia normalizado por impacto y un modelo de regresión lineal. Severidades altas influyeron negativamente en la resiliencia ingenieril a corto plazo de las comunidades de matorral dominadas por especies germinadoras facultativas. En cambio, las comunidades dominadas por especies rebrotadoras alcanzaron valores de cobertura pre-incendio independientemente de la severidad del fuegoEste estudio ha sido financiado por el Ministerio de Economía y Competitividad de España, y el Fondo Europeo de Desarrollo Regional (FEDER), en el marco de los proyectos GESFIRE (AGL2013- 48189-C2-1-R) y FIRESEVES (AGL2017-86075-C2-1-R); y por la Junta de Castilla y León en el marco de los proyectos FIRECYL (LE033U14), SEFIRECYL (LE001P17) y WUIFIRECYL (LE005P20)

Experimental results on constructed wetland pilot system

pp. 387-392La investigación de un humedal artificial para el tratamiento de aguas residuales mediante MHEA (Jerárquica mosaico de ecosistemas artificiales). El sistema consistía en un estanque de agua libre como una primera etapa de trabajo como tratamiento primario seguida de una zona con Typha sp. y el flujo de superficie y, finalmente, una zona arbolada con un flujo subsuperficial y plantado con especies leñosas (Salixsp., Populus sp., Fraxinus sp. y Alnus sp.S

Depuración integral de aguas residuales mediante un sistema natural de bajo coste

El sistema elimina eficazmente tanto materia orgánica como contaminación fecal. Aunque los valores medios de reducción no son todo lo elevados que cabría esperar debido a que el sistema está en fase de estabilización, sólo se excede el vertido establecido legalmente en ocasiones puntuale

Swine waste tertiary treatment for nitrogen removal by a constucted wetland

Los residuos porcinos causan una gran preocupación agrícola y ambiental debido a las enormes cantidades de residuos generados y la contaminación de las aguas superficiales y subterráneas. Se ha establecido un estudio sobre el tratamiento de las aguas residuales mediante humedales artificiales porcinos en España, en julio de 2002. El sistema está compuesto de dos series de tres tanques, con diferente caudal. Muestras de aguas residuales y efluentes se ha analizado para sólidos totales y volátiles en suspensión (TSS, VSS); cinco días la demanda bioquímica de oxígeno (DBO5); la demanda química de oxígeno (DQO); nitrógeno total Kjedahl (NTK); nitrógeno de amonio; nitrato y nitrito de nitrógeno. El objetivo era determinar la eficiencia de eliminación de nitrógeno en ambas series: Typha-Pharagmites (S1) y Typha-Salix (S2). El sistema está todavía en fase de estabilización, pero los datos parecen sugerir que S1 es mejor en la eliminación de N en la forma NH4-N (92%) que S2, pero esto es más eficaz en la eliminación del N total (64%) como S1 (60%