Efectos del cambio global en la estructura trófica de los humedales a través del uso de isótopos estables

El Capítulo I en inglésEvaluar los efectos de los diferentes motores del cambio global en la estructura trófica de los humedales (semiáridos) a través del estudio de los registros isotópicos de 13C y 15N de productores y consumidores para determinar los impactos en la calidad ecológica y en la estabilidad de los ecosistemas.Effects of shrimp-farm effluents on the food web structure in subtropical coastal lagoons. http://dx.doi.org/10.1016/j.jembe.2011.03.019. http://hdl.handle.net/10261/127847Peer reviewe

Efectos del cambio global en la estructura trófica de los humedales a través del uso de isótopos estables

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Ecología. Fecha de lectura: 17-12-201

Phosphorus and water supply independently control productivity and soil enzyme activity responses to elevated CO2 in an understorey community from a Eucalyptus woodland

Aims While it is well-established that nitrogen (N) availability regulates elevated [CO2] (eCO(2)) effects on plant growth and soil carbon (C) storage in N-limited environments, there are fewer studies investigating the role of phosphorous (P) supply on such responses in P-limited environments. In this study, we explored whether P fertilization influences the response of plant growth, soil enzyme activity and C fluxes to eCO(2), and determined how different levels of water availability regulate these processes. Methods We used soil collected from a temperate, P-limited Eucalyptus woodland containing the native soil seed bank to grow a potted replica of local understory communities. We exposed the emerging communities to eCO(2) under two contrasting water levels and two levels of P fertilization. We assessed plant biomass allocation, the rhizosphere activity of extracellular enzymes related to C, N and P cycles, and pot-level CO2 fluxes. Results The positive effects of eCO(2) on plant production and ecosystem C dynamics were strongly constrained by low levels of P availability. Enhanced water supply increased rhizosphere enzyme activity with minor impacts on plant biomass responses to eCO(2.) Our data also suggest that plant and microbial mechanisms that increase nutrient release from SOM may not be able to overcome this P limitation. Conclusions While current Earth System Models predict positive feedback responses of terrestrial ecosystems on C storage under eCO(2), here we emphasize the importance of accounting for the widespread phenomenon of P-limitation in such responses

Plant Multi-element Coupling as an Indicator of Nutritional Mismatches Under Global Change

Global biogeochemical cycles have been widely altered due to human activities, potentially compromising the ability of plants to regulate their metabolism. We grew experimental herbaceous communities simulating the understory of eucalypt forests from southeastern Australia to evaluate the effects of elevated CO2 (400 vs. 650 ppm) and changes in soil resource availability (high-low water and high-low P) on the concentration of fourteen essential plant macro- and micronutrients, and their degree of coupling. Coupling was based on correlations among all elements in absolute value and a null modeling approach. According to the ancient nature of Australian soils, P addition was the main driver of changes in plant tissue chemistry, increasing the concentrations of P, Mg, Ca, and Mn and reducing the concentrations of C, N, S, Na, and Cu. Most treatment combinations showed coupled patterns of plant elements, particularly under ambient CO2. However, under elevated CO2, elements in plant tissues became more decoupled, which was interpreted as the result of a lack of enough supply of a range of elements to satisfy greater demands. Across treatments, P, Mn, and N were the least coupled elements, while K, Ca, and Fe were the most coupled ones. We provide evidence that plant element coupling was positively related to the concentration and coupling of elements measured in soils worldwide, suggesting that plant element coupling is conserved. Our results provide compelling evidence that evaluating the coupling of a representative range of chemical elements in plant tissues may represent a highly novel and powerful indicator of nutritional mismatches between demand and supply under specific environmental circumstances, including in a resource-altered global change context

Effects of shrimp-farm effluents on the food web structure in subtropical coastal lagoons

Received 4 October 2010, Revised 24 March 2011, Accepted 29 March 2011, Available online 19 April 2011Although numerous studies have reported the negative effects of shrimp aquaculture on water quality, little is known about the ecological effects of these practices in coastal lagoons and near-shore marine habitats. The impact of shrimp-farm effluents on the food webs of an impacted subtropical coastal lagoon in the Gulf of California was evaluated through measurements of isotopic (δ13C, δ15N) signatures in sediments, plants and animals, and compared with the results of a near-pristine reference site. Degradation was manifested in a strong reduction on fish diversity at the perturbed site. δ13C signatures provided ambiguous evidence of degradation while δ15N was a better descriptor of shrimp-farm effluent impact on coastal lagoon food webs. The site receiving nutrient-rich discharges showed significant enrichment of δ15N (≈ 5‰) in sediments, macroalgae, benthic algae, filterfeeders and omnivorous feeders, resulting in qualitative differences in foodweb structure between both lagoons. The food web in the perturbed site was sustained by sediment detritus and dominated by opportunistic species. The lowest influence on δ15N signatures by aquaculture discharges recorded in the upper trophic levels could be explained by the shift in the composition of biotic communities, and associated feeding strategies. While alterations in resource availability do not affect directly food chain length, trophic linkages between food web compartments can be reduced as a result of shrimp farm impacts. Our study demonstrates that nutrient-enriched discharges from shrimp-farm aquaculture generate changes in the availability of food sources, which reduce biodiversity and alter structural and functional food web characteristics.This research was supported by the Mexican Secretary of Natural Resources and Environment (SEMARNAT-CONACYT; contract SEMAR-NAT-2002-C01-0147) and by the Spanish Ministry of Environment (Organismo Autónomo Parques Nacionales; contracts 2008/001 DECA-MERON and 81/2005 CARBONDA.Peer reviewe

Nature-based strategies to regenerate the functioning and biodiversity of vineyards

16 páginas.- 2 figuras.- 1 Box.- 138 referenciasGrapevine is one of the most important perennial fruit crops worldwide. Historically, vineyards were compatible with soil conservation practices and multitrophic biodiversity, but vineyards are now generally eroded and biologically impoverished, making them more susceptible to pests and diseases. However, the idiosyncrasy of the wine sector places wine growers in a unique position to lead the adoption of a range of sustainable management strategies and, thus, to pioneer a wider transformation of the agricultural sector. In this article, we provide an overview of nature-based management strategies that may be used for the regeneration of the functioning and biodiversity of vineyards and that may also lead to improved plant nutrition, grape berry quality and the suppression of pathogens and pests. These strategies include the use of microbial and nonmicrobial biostimulants, fertilization with organic amendments as well as foliar fertilization with nature-based products, the use of cover crops and the reintegration of livestock in vineyards, especially sheep. We will also pay special attention to the implementation of circular economy in the vineyard in relation to the previously mentioned management strategies and will also discuss the importance of considering all these aspects from a holistic and integrative perspective, rather than taking them into account as single factors. Assuming the integral role of soils in the functioning of agroecosystems, soils will be considered transversally across all sections. Finally, we will argue that the time is now ripe for innovation from the public and private sectors to contribute to the sustainable management of vineyards while maintaining, or even improving, the profit margin for farmers and winemakers.This review article is, in part, the result of a workshop (I Jornadas ‘Suelos Vivos’ para la regeneración de la vida en suelos de viñedos gaditanos; https://suelosvivos.es/i-jornadas-suelos-vivos/) carried out within the context of the ‘Suelos Vivos’ Regional Operational Group of the EIP-Agri, which was celebrated between 23 and 24 March 2023 in Puerto Real, Cádiz. Raúl Ochoa-Hueso was supported by the Ramón y Cajal programme from the MICINN (RYC-2017 22032), by the Spanish Ministry of Science and Innovation for the I + D + i project PID2019-106004RA-I00 funded by MCIN/AEI/10.13039/501100011033, by the Fondo Europeo de Desarrollo Regional (FEDER) y la Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the Junta de Andalucía (FEDER Andalucía 2014-2020 Objetivo temático ‘01 - Refuerzo de la investigación, el desarrollo tecnológico y la innovación’): P20_00323 (FUTUREVINES), and by the Fondo Europeo Agrícola de Desarrollo Rural (FEADER) through the ‘Ayudas a Grupos operativos de la Asociación Europea de Innovación (AEI) en materia de productividad y sostenibilidad agrícolas’, Referencia: GOPC-CA-20-0001. Manuel Delgado-Baquerizo acknowledges support from TED2021-130908B-C41/AEI/10.13039/501100011033/Unión Europea NextGenerationEU/PRTR and from the Spanish Ministry of Science and Innovation for the I + D + i project PID2020-115813RA-I00 funded by MCIN/AEI/10.13039/501100011033. Cristina Lazcano acknowledges support from the California Department of Food and Agriculture (21-0433-021-SF) and the Foundation for Food and Agriculture Research (FFAR, CA21-SS-0000000193). Lilia Serrano-Grijalva thanks the European Union's Horizon 2020 research and innovation programme who funded her work under the Marie Skłodowska-Curie Grant Agreement No. 890874Peer reviewe

Bioavailability of Macro and Micronutrients Across Global Topsoils: Main Drivers and Global Change Impacts

Understanding the chemical composition of our planet\u27s crust was one of the biggest questions of the 20th century. More than 100 years later, we are still far from understanding the global patterns in the bioavailability and spatial coupling of elements in topsoils worldwide, despite their importance for the productivity and functioning of terrestrial ecosystems. Here, we measured the bioavailability and coupling of thirteen macro- and micronutrients and phytotoxic elements in topsoils (3–8 cm) from a range of terrestrial ecosystems across all continents (∼10,000 observations) and in response to global change manipulations (∼5,000 observations). For this, we incubated between 1 and 4 pairs of anionic and cationic exchange membranes per site for a mean period of 53 days. The most bioavailable elements (Ca, Mg, and K) were also amongst the most abundant in the crust. Patterns of bioavailability were biome-dependent and controlled by soil properties such as pH, organic matter content and texture, plant cover, and climate. However, global change simulations resulted in important alterations in the bioavailability of elements. Elements were highly coupled, and coupling was predictable by the atomic properties of elements, particularly mass, mass to charge ratio, and second ionization energy. Deviations from the predictable coupling-atomic mass relationship were attributed to global change and agriculture. Our work illustrates the tight links between the bioavailability and coupling of topsoil elements and environmental context, human activities, and atomic properties of elements, thus deeply enhancing our integrated understanding of the biogeochemical connections that underlie the productivity and functioning of terrestrial ecosystems in a changing world

Microbial community associations in soil aggregates in response to diversified crop rotations

This poster was part of the 2022 Microbial Ecology course. https://www.pe-rc.nl/microbial-ecology202

A Free Air CO2 Enrichment (FACE) Facility in a Wetland to Study the Effects of Elevated Atmospheric Carbon Dioxide: System Description and Performance

The Free Air CO2 Enrichment (FACE) system has proved suitable for exposing plants to elevated [CO2] with minimal disturbance of their natural environment. Here we describe a FACE facility in a floodplain wetland in detail and, additionally, its performance after the first year of operation (2012). The FACE system consisted of six 3-m diameter emission rings in which Phragmitesaustralis was grown. The target [CO2] was 550 μmol mol−1 and fertilization was carried out continuously. Daily temporal [CO2] performance was adequate with 61 and 83 % of air samples at the ring’s centre having a [CO2] within 10 and 20 % of the target, respectively, with values closest to their target during summer months and daytime. Spatial [CO2] distribution showed no significant gradients across the ring. Increased wind speed improved the system’s spatial performance, as [CO2] was within ±10 % of the target in the whole ring. Across the entire fertilization season, CO2 requirements for maintaining a mean [CO2] of 582 μmol mol−1 in wetland plots averaged 17.4 kg CO2 ring−1 day−1. Our requirements (2.5 kg CO2 m−2 day−1) were very low compared to other FACE systems, demonstrating its high potential to study the effects of elevated CO2 in wetlands at low cost.The DECAMERON project (2008/001) funded by the Agency for National Parks of the Spanish Ministry of Agriculture, Food and Environment, provided financial support for the wetland FACE facility. RMwas a FPI fellowship; LSGand RSAwere supported by JAE-PreDoc and JAE-Doc contracts respectively co-funded by the European Social Funds.Peer Reviewe

Germination of crop species in response to whole-soil inoculants that originate from conventional vs organic farming systems

<p>Dataset of manuscript entitled “Germination of crop species in response to whole-soil inoculants that originate from conventional vs organic farming systems”. This manuscript includes the results of WP2 from the SOFT project (ref. 890874).</p&gt