Validation of and comparison between a semidistributed rainfall-runoff hydrological model (PREVAH) and a spatially distributed snow-evolution model (SnowModel) for snow cover prediction in mountain ecosystems

Snow cover is an important control in mountain environments and a shift of the snow-free period triggered by climate warming can strongly impact ecosystem dynamics. Changing snow patterns can have severe effects on alpine plant distribution and diversity. It thus becomes urgent to provide spatially explicit assessments of snow cover changes that can be incorporated into correlative or empirical species distribution models (SDMs). Here, we provide for the first time a with a lower overestimation comparison of two physically based snow distribution models (PREVAH and SnowModel) to produce snow cover maps (SCMs) at a fine spatial resolution in a mountain landscape in Austria. SCMs have been evaluated with SPOT-HRVIR images and predictions of snow water equivalent from the two models with ground measurements. Finally, SCMs of the two models have been compared under a climate warming scenario for the end of the century. The predictive performances of PREVAH and SnowModel were similar when validated with the SPOT images. However, the tendency to overestimate snow cover was slightly lower with SnowModel during the accumulation period, whereas it was lower with PREVAH during the melting period. The rate of true positives during the melting period was two times higher on average with SnowModel with a lower overestimation of snow water equivalent. Our results allow for recommending the use of SnowModel in SDMs because it better captures persisting snow patches at the end of the snow season, which is important when modelling the response of species to long-lasting snow cover and evaluating whether they might survive under climate change.

What can ecosystems learn? Expanding evolutionary ecology with learning theory.

BACKGROUND: The structure and organisation of ecological interactions within an ecosystem is modified by the evolution and coevolution of the individual species it contains. Understanding how historical conditions have shaped this architecture is vital for understanding system responses to change at scales from the microbial upwards. However, in the absence of a group selection process, the collective behaviours and ecosystem functions exhibited by the whole community cannot be organised or adapted in a Darwinian sense. A long-standing open question thus persists: Are there alternative organising principles that enable us to understand and predict how the coevolution of the component species creates and maintains complex collective behaviours exhibited by the ecosystem as a whole? RESULTS: Here we answer this question by incorporating principles from connectionist learning, a previously unrelated discipline already using well-developed theories on how emergent behaviours arise in simple networks. Specifically, we show conditions where natural selection on ecological interactions is functionally equivalent to a simple type of connectionist learning, 'unsupervised learning', well-known in neural-network models of cognitive systems to produce many non-trivial collective behaviours. Accordingly, we find that a community can self-organise in a well-defined and non-trivial sense without selection at the community level; its organisation can be conditioned by past experience in the same sense as connectionist learning models habituate to stimuli. This conditioning drives the community to form a distributed ecological memory of multiple past states, causing the community to: a) converge to these states from any random initial composition; b) accurately restore historical compositions from small fragments; c) recover a state composition following disturbance; and d) to correctly classify ambiguous initial compositions according to their similarity to learned compositions. We examine how the formation of alternative stable states alters the community's response to changing environmental forcing, and we identify conditions under which the ecosystem exhibits hysteresis with potential for catastrophic regime shifts. CONCLUSIONS: This work highlights the potential of connectionist theory to expand our understanding of evo-eco dynamics and collective ecological behaviours. Within this framework we find that, despite not being a Darwinian unit, ecological communities can behave like connectionist learning systems, creating internal conditions that habituate to past environmental conditions and actively recalling those conditions. REVIEWERS: This article was reviewed by Prof. Ricard V Solé, Universitat Pompeu Fabra, Barcelona and Prof. Rob Knight, University of Colorado, Boulder.

Predicting the future effectiveness of protected areas for bird conservation in Mediterranean ecosystems under climate change and novel fire regime scenarios

AimGlobal environmental changes challenge traditional conservation approaches based on the selection of static protected areas due to their limited ability to deal with the dynamic nature of driving forces relevant to biodiversity. The Natura 2000 network (N2000) constitutes a major milestone in biodiversity conservation in Europe, but the degree to which this static network will be able to reach its long-term conservation objectives raises concern. We assessed the changes in the effectiveness of N2000 in a Mediterranean ecosystem between 2000 and 2050 under different combinations of climate and land cover change scenarios. LocationCatalonia, Spain. MethodsPotential distribution changes of several terrestrial bird species of conservation interest included in the European Union's Birds Directive were predicted within an ensemble-forecasting framework that hierarchically integrated climate change and land cover change scenarios. Land cover changes were simulated using a spatially explicit fire-succession model that integrates fire management strategies and vegetation encroachment after the abandonment of cultivated areas as the main drivers of landscape dynamics in Mediterranean ecosystems. ResultsOur results suggest that the amount of suitable habitats for the target species will strongly decrease both inside and outside N2000. However, the effectiveness of N2000 is expected to increase in the next decades because the amount of suitable habitats is predicted to decrease less inside than outside this network. Main conclusionsSuch predictions shed light on the key role that the current N2000may play in the near future and emphasize the need for an integrative conservation perspective wherein agricultural, forest and fire management policies should be considered to effectively preserve key habitats for threatened birds in fire-prone, highly dynamic Mediterranean ecosystems. Results also show the importance of considering landscape dynamics and the synergies between different driving forces when assessing the long-term effectiveness of protected areas for biodiversity conservation.

Longer and less overlapping food webs in anthropogenically disturbed marine ecosystems: confirmations from the past

The human exploitation of marine resources is characterised by the preferential removal of the largest species. Although this is expected to modify the structure of food webs, we have a relatively poor understanding of the potential consequences of such alteration. Here, we take advantage of a collection of ancient consumer tissues, using stable isotope analysis and SIBER to assess changes in the structure of coastal marine food webs in the South-western Atlantic through the second half of the Holocene as a result of the sequential exploitation of marine resources by hunter-gatherers, western sealers and modern fishermen. Samples were collected from shell middens and museums. Shells of both modern and archaeological intertidal herbivorous molluscs were used to reconstruct changes in the stable isotopic baseline, while modern and archaeological bones of the South American sea lion Otaria flavescens, South American fur seal Arctocephalus australis and Magellanic penguin Spheniscus magellanicus were used to analyse changes in the structure of the community of top predators. We found that ancient food webs were shorter, more redundant and more overlapping than current ones, both in northern-central Patagonia and southern Patagonia. These surprising results may be best explained by the huge impact of western sealing on pinnipeds during the fur trade period, rather than the impact of fishing on fish populations. As a consequence, the populations of pinnipeds at the end of the sealing period were likely well below the ecosystem's carrying capacity, which resulted in a release of intraspecific competition and a shift towards larger and higher trophic level prey. This in turn led to longer and less overlapping food webs.

Interpretación ambiental de INBioparque, La Finca (Costa Rica)

Este artículo es una síntesis del proyecto realizado en INBio (Instituto Nacional de Biodiversidad), Costa Rica, cuyo objetivo principal fue la mejora de la Interpretación Ambiental de INBioparque, un parque temático de biodiversidad dentro de la institución. INBioparque está situado en Santo Domingo de Heredia, provincia de Heredia, Costa Rica. Éste pretende hacer una pequeña representación de los principales ecosistemas que se encuentran en el país. El parque se divide en diferentes zonas: Bosque del Valle Central, Bosque Húmedo, Bosque Seco, Humedal y Finca. En esta última, la Finca (ecosistema basado en la biodiversidad domesticada) es dónde se ha centrado todo el proyecto, debido a que presentaba una mayor necesidad de mejora en su interpretación ambiental. La Interpretación ambiental traduce el lenguaje técnico de los profesionales a términos e ideas más entendedoras para todos los públicos. Pretende promover una nueva conciencia sobre el valor de la biodiversidad, lograr su conservación y mejorar la calidad de vida del ser humano. El proyecto propone la mejora de la interpretación ambiental a través de las fichas técnicas elaboradas de las diferentes especies vegetales de la Finca, así como la renovación o creación de rótulos explicativos. Se propone también un recorrido guiado y auto guiado para hacer más entendedora la visita, además de algunas actividades y talleres.

The Problem of Invasive Species in River Ecosystems

Invasive nonnative species are a major problem in river ecosystems, and have large ecological and economic costs. Few ecosystems can resist invasions. The species that tend to invade most readily are those that humans. Introduce the most, and the ecosystems they invade are those with the most human activity. Most invasions are irreversible, and control is expensive, so efforts should be focused on prevention of future invasions

Crustacean and aquatic insect assemblages in the Mediterranean coastal ecosystems of Empord`a wetlands (NE Iberian peninsula)

Coastal wetlands are characterized by high biodiversity, which is one of the main criteria considered when establishing protection policies or when proposing adequate management actions. In this study, the crustacean and aquatic insect composition of the Empord`a wetlands is described. These two faunal groups contribute highly to the total biodiversity in these wetlands but are seldom considered when managing natural areas. A selection (84 sampling points) of all water body types present in the Empord`a wetlands were sampled monthly (surber and dip net with a 250 μm mesh). Sampling was carried out during 3 surveys (1991-92, 1996-97 and 1999-2000). A rich fauna of 125 crustacean and 295 aquatic insect taxa was identified. We characterized each water body type using the most abundant species and the relative species richness of the taxonomic groups. A classification of the water body types, according to similarity between inventories, groups the brackish and hyperhaline systems in one cluster and the various freshwater systems in another one. Among freshwater systems, lotic waters and freshwater wetlands have a high similarity, whereas rice fields and freshwater springs have a low similarity

Organic carbon and nutrient (P, N) concentrations of water and sediment in several aquatic environment types of a Mediterranean coastal wetland (Empordà Wetlands, NE Iberian Peninsula)

Total sediment and water organic carbon and nutrient (nitrogen and phosphorus) concentrations of different environment types of a Mediterranean coastal wetland (temporary and brackish, temporary and freshwater, semi-permanent and brackish, and permanent and brackish basins) were analysed during two hydroperiods. A nitrogen limitation was found for both sediment and water. The total organic carbon concentration of the water was significantly related to the water level, which varies throughout the hydroperiods. In contrast, the total organic carbon concentration of the sediment was not related to water level. However, significant differences in total organic carbon of the sediment were found between hydroperiods. On the other hand, total organic carbon of the sediment varied spatially, being higher in temporary brackish basins with lower sand content, and lower in permanent and semi-permanent brackish basins with higher sand content

Floristic composition of two wetland forests in Araguaian Plain, State of Tocantins, Brazil, and comparison with other areas

Seasonally inundated native forest fragments ("ipucas") located in natural landform depression swales of the Araguaian Plain are currently under land use pressure. Their composition needs to be better understood to guarantee their protection. This comparative study of fragments under different land use conditions was carried out at Lago Verde Farm, Lagoa da Confusão,Tocantins, Brazil. The location coordinates are UTM 643586 and 644060 East and 8792795 and 8799167 North. This study aimed to first analyze and compare the floristic composition of two seasonally inundated forest fragments of approximately one hectare each. The first is located in an intact (without human intervention) Gramineous-Woody Savanna region and the second in a rice cultivation region. The floristic composition of both fragments was then compared to that of other wetland forests located in the Northern, Central Western and Southeastern regions of Brazil.All the floristic compositions are affected by seasonal flooding and soil water saturation. The floristic inventory used a census method that sampled all trees and shrubs with perimeter at 1.30 m from soil (PAP) = 15cm; 665 individuals, 33 families and 49 species were recorded for the intact region and 807 individuals, 35 families and 70 species for the altered region fragment. The values of H' = 0.806 (Shannon-Weaver) and J = 3.44 nats /individual (equability) for the fragment in the region affected by rice cultivation are considered high compared to the intact region fragment values (H' = 0.761 and J = 2.97). Families contributing to floristic richness in the altered region fragment were Fabaceae (9 species), Vochysiaceae (6) and Annonaceae (4). In the intact region fragment, Fabaceae also presented the largest number of species (8) followed by Arecaceae, Chrysobalanaceae and Vochysiaceae (3 each). When comparing the forests from various regions in Brazil, floristic similarity was found to be small. Greater similarity was found when indices for the two Lagoa da Confusão fragments were compared to riparian forests located in the Federal District of Brasilia.

Influence of pioneer-species combinations on restoration of disturbed ecosystems in the Atlantic Forest, Rio de Janeiro, Brazil

The analysis of species composition and its effects on sustainability restoration processes in the Atlantic Forest with poor environmental attributes is important to improve rehabilitation techniques for disturbed ecosystems. Reforestation projects were used as Biological Measures (BM) of rehabilitation, where treatments differ in the composition of exotic species, utilized as anthropic pioneers: BM1 - 82% (73% Mimosa caesalpiniifolia Benth, 9% Eucalyptus citriodora Hook.); BM2 - 91% (9%, 82%); and BM3 - 25% (15%, 10%). The monitoring of spontaneous regeneration was evaluated in three 12-year-old reforestation sites between thr rainy season of 2004 and 2005, and compared with an approximately 100-year-old native forest fragment and a grassland: ecosystems with inertial tendency toward recuperation and degradation, respectively. It was detected that exotic species used as anthropic pioneers strongly influenced regeneration: BM1 (75%), BM2 (85%), BM3 (55%), Forest (0%) and Grassland (50%). The highest similarity of species with forest regeneration (5%) was found for treatment BM3.

Removal of nitrogen, phosphorus, copper and zinc from swine breeding waste water by bermudagrass and cattail in constructed wetland systems

This work aimed to study the agronomic performance and capacity of nutrient removal by bermudagrass (Cynodon spp.) and cattail (Typha sp.) when grown in constructed wetlands systems (CWSs) of vertical and horizontal flow, respectively, used in the post-treatment of swine breeding wastewater (ARS). The average yield of dry matter (DM) of bermudagrass in sections of 60-day interval ranged from 14 to 43 t ha-1, while the cultivated cattail produced in a single cut after 200 days of cultivation between 45 and 67 t ha-1 of DM. Bermudagrass extracted up to 17.65 kg ha-1 d-1 of nitrogen, 1.76 kg ha-1 d-1 of phosphorus, 6.67 g ha-1 d-1 of copper and 54.75 g ha-1 d-1 of zinc. Cattail extracted up to 5.10 kg ha-1 d-1 of nitrogen, 1.07 kg ha-1 d-1 of phosphorus, 1.41 g ha-1 d-1 of copper and 16.04 g ha-1 d-1 of zinc. Cattail and bermudagrass were able to remove, respectively, 5.0 and 4.6% of the nitrogen and 11.2 and 5.4% of the phosphorus applied via ARS, being less efficient in extracting N and P when the initial intake of these nutrients is evaluated.

SobekCM’s Community Ecosystems & Socio-Technical Practices

Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

Building Successful, Open Repository Software Ecosystems: Technology and Community

Panel at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014