Browsing by Issue Date, starting with "2022-08"
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- Genomic analyses show extremely perilous conservation status of African and Asiatic cheetahs ( Acinonyx jubatus )Publication . Prost, Stefan; Machado, Ana Paula; Zumbroich, Julia; Preier, Lisa; Mahtani‐Williams, Sarita; Meissner, Rene; Guschanski, Katerina; Brealey, Jaelle C.; Fernandes, C; Vercammen, Paul; Hunter, Luke T. B.; Abramov, Alexei V.; Plasil, Martin; Horin, Petr; Godsall‐Bottriell, Lena; Bottriell, Paul; Dalton, Desire Lee; Kotze, Antoinette; Burger, Pamela AnnaWe live in a world characterized by biodiversity loss and global environmental change. The extinction of large carnivores can have ramifying effects on ecosystems like an uncontrolled increase in wild herbivores, which in turn can have knock-on impacts on vegetation regeneration and communities. Cheetahs (Acinonyx jubatus) serve important ecosystem functions as apex predators; yet, they are quickly heading towards an uncertain future. Threatened by habitat loss, human-wildlife conflict and illegal trafficking, there are only approximately 7100 individuals remaining in nature. We present the most comprehensive genome-wide analysis of cheetah phylogeography and conservation genomics to date, assembling samples from nearly the entire current and past species' range. We show that their phylogeography is more complex than previously thought, and that East African cheetahs (A. j. raineyi) are genetically distinct from Southern African individuals (A. j. jubatus), warranting their recognition as a distinct subspecies. We found strong genetic differentiation between all classically recognized subspecies, thus refuting earlier findings that cheetahs show only little differentiation. The strongest differentiation was observed between the Asiatic and all the African subspecies. We detected high inbreeding in the Critically Endangered Iranian (A. j. venaticus) and North-western (A. j. hecki) subspecies, and show that overall cheetahs, along with snow leopards, have the lowest genome-wide heterozygosity of all the big cats. This further emphasizes the cheetah's perilous conservation status. Our results provide novel and important information on cheetah phylogeography that can support evidence-based conservation policy decisions to help protect this species. This is especially relevant in light of ongoing and proposed translocations across subspecies boundaries, and the increasing threats of illegal trafficking.
- Concurrent herbivory and metal accumulation: The outcome for plants and herbivoresPublication . Godinho, Diogo; Serrano, Helena Cristina; Magalhães, sara; Branquinho, CristinaThe effects of metals on plants and herbivores, as well as the interaction among the latter, are well documented. However, the effects of simultaneous herbivory and metal accumulation remain poorly studied. Here, we shed light on this topic by infesting cadmium-accumulating tomato plants (Solanum lycopersicum), either exposed to cadmium or not, with herbivorous spider mites, Tetranychus urticae or T. evansi during 14 days. Whereas on plants without cadmium T. evansi had higher growth rate than T. urticae, on plants with cadmium both mite species had similar growth rates, which were lower than on plants without metal. Plants were affected by both cadmium toxicity and by herbivory, as shown by leaf reflectance, but not on the same wavelengths. Moreover, changes in leaf reflectance on the wavelength affected by herbivores were similar on plants with and without cadmium, and vice versa. Long-term effects of cadmium and herbivory did not affect H2O2 concentrations in the plant. Finally, plants infested with spider mites did not accumulate more cadmium, suggesting that metal accumulation is not induced by herbivory. We thus conclude that cadmium accumulation affects two congeneric herbivore species differently and that the effects of herbivory and cadmium toxicity on plants may be disentangled, via leaf reflectance, even during simultaneous exposure.
- A central place foraging seabird flies at right angles to the wind to jointly optimize locomotor and olfactory search efficiencyPublication . Ventura, Francesco; Catry, Paulo; Dias, Maria P.; Breed, Greg A.; Folch, Arnau; Granadeiro, José PedroTo increase the probability of detecting odour plumes, and so increase prey capture success, when winds are stable central place foraging seabirds should fly crosswind to maximize the round-trip distance covered. At present, however, there is no empirical evidence of this theoretical prediction. Here, using an extensive GPS tracking dataset, we investigate, for the first time, the foraging movements of Bulwer's petrels (Bulweria bulwerii) in the persistent North Atlantic trade winds. To test the hypotheses that, in stable winds, petrels use crosswind to maximize both the distance covered and the probability of detecting olfactory cues, we combine state-space models, generalized additive models and Gaussian plume models. Bulwer's petrels had the highest degree of selectivity for crosswinds documented to date, often leading to systematic zig-zag flights. Crosswinds maximized both the distance travelled and the probability of detecting odour plumes integrated across the round-trip (rather than at any given point along the route, which would result in energetically costly return flight). This evidence suggests that petrels plan round-trip flights at departure, integrating expected costs of homeward journeys. Our findings, which are probably true for other seabirds in similar settings, further highlight the critical role of wind in seabird foraging ecology.
- An annotated checklist of the vascular flora of Quiçama National Park, AngolaPublication . MONTEIRO, FRANCISCA; DA COSTA, ESPERANÇA; KISSANGA, RAQUEL; COSTA, JOSÉ CARLOS; Catarino, LuísThe Quiçama National Park (PNQ), located in Luanda Province, Angola, is one of the oldest protected areas in the country. Although some work has been done on the flora of the Park, up to now a comprehensive record of the vascular plant species has been lacking. The objective of the present study was to produce an inventory of the vascular plant diversity of PNQ, as well as to record the types of vegetation in which each species occurs, their habits, uses by local communities, common names, and conservation status. A total of 452 species were recorded, from 285 genera and 85 families. Two species are Pteridophytes, 99 are Monocotyledons, and 351 are Dicotyledons. The two largest families of the PNQ flora are the Fabaceae and the Poaceae. The Park hosts 14 species endemic to Angola, and one of them is restricted to this protected area. Of the 128 species with data on conservation status, 109 are considered of least concern, 13 are vulnerable, and six are endangered. Regarding useful plants, 237 species from 67 families were recorded. Of these, 196 are Dicotyledons and 41 are Monocotyledons. Most of them are used for medicinal purposes, the manufacturing of artefacts, and as sources of food.
- Rethinking the sustainable development goals: Learning with and from community‐led initiativesPublication . Henfrey, Tom; Feola, Giuseppe; Penha-Lopes, Gil; Sekulova, Filka; Esteves, Ana MargaridaThis paper explores the actual and potential contributions of community-led initiatives (CLIs) to the Sustainable Development Goals (SDGs). As examples of self-determined practical action for sustainability and social justice, CLIs prefigure many of the intended outcomes of the SDGs. Existing evidence shows that CLIs are already contributing, at local scale, to almost all of the SDGs, and achieving particular success in bringing different goals into synergy. However, these achievements are based on ethics, guiding philosophies, issue framings, practical goals and ways of organising that differ significantly from those behind the formulation and delivery of the SDGs. Embracing those differences, and with them greater plurality and ongoing critical self-reflection, would allow the SDGs to transcend certain self-limiting contradictions, particularly concerning the role of economic growth. Such a shift in orientation is essential if the SDGs are to move from reinforcing to challenging the root causes of unsustainability and injustice.
- Modelling the role of ground-true riparian vegetation for providing regulating services in a Mediterranean watershedPublication . Aparício, Bruno A.; Nunes, João Pedro; Bernard-Jannin, Léonard; Dias, Luís Filipe; Fonseca, André; Ferreira, TeresaIntensive agricultural and industrial activities are often considered major sources of water contamination. Currently, riparian vegetation (RV) is increasingly being promoted as a solution to balance the potentially adverse effects that agriculture may have on water quality. Nonetheless, existing RV is often overlook in recent modelling efforts, failing to capture the current amount of ecosystem services provide. Here, we used the Soil and Water Assessment Tool ecohydrological model to simulate the influence of ground-true RV on i) nutrient (nitrate and total phosphorus) and sediment exports from agricultural areas and ii) its effect for in-stream concentrations. These results are further compared against a set of hypothetical scenarios of different RV widths and different land-uses. Our results point to a great relevance of existing RV in controlling in-stream concentration of sediments and nutrients where pressure from agriculture is highest, preventing them to surpass limits set in the EU Water Framework Directive. On the other hand, in areas with industry discharges, the role of RV is limited and model results suggest that restoring RV would have limited impacts. We illustrate how existing RV may already provide strong but not acknowledged water quality regulation services, how these services can differ substantially between nearby streams, and that effective strategies to improve water quality using RV must acknowledge existing patterns of vegetation, land use and contamination sources.
- Nutrient-limited subarctic caves harbour more diverse and complex bacterial communities than their surface soilPublication . Sofia Reboleira, Ana; Bodawatta, Kasun H.; Ravn, Nynne M. R.; Lauritzen, Stein-Erik; Skoglund, Rannveig Øvrevik; Poulsen, Michael; Michelsen, Anders; Jønsson, Knud AndreasBackground: Subarctic regions are particularly vulnerable to climate change, yet little is known about nutrient availability and biodiversity of their cave ecosystems. Such knowledge is crucial for predicting the vulnerability of these ecosystems to consequences of climate change. Thus, to improve our understanding of life in these habitats, we characterized environmental variables, as well as bacterial and invertebrate communities of six subarctic caves in Northern Norway. Results: Only a minuscule diversity of surface-adapted invertebrates were found in these caves. However, the bacte‑ rial communities in caves were compositionally diferent, more diverse and more complex than the nutrient-richer surface soil. Cave soil microbiomes were less variable between caves than between surface communities in the same area, suggesting that the stable cave environments with tougher conditions drive the uniform microbial communi‑ ties. We also observed only a small proportion of cave bacterial genera originating from the surface, indicating unique cave-adapted microbial communities. Increased diversity within caves may stem from higher niche specialization and levels of interdependencies for nutrient cycling among bacterial taxa in these oligotrophic environments. Conclusions: Taken together this suggest that environmental changes, e.g., faster melting of snow as a result of global warming that could alter nutrient infux, can have a detrimental impact on interactions and dependencies of these complex communities. This comparative exploration of cave and surface microbiomes also lays the founda‑ tion to further investigate the long-term environmental variables that shape the biodiversity of these vulnerable ecosystems.
- Multi-Target Alternative Approaches to Promoting Fresh-Cut Carrots’ Bioactive and Fresh-like QualityPublication . Alegria, C.; Gonçalves, Elsa M.; Moldão, Margarida; Abreu, MartaFresh-cut fruits and vegetables, as near-fresh foods, are a quick and easy solution to a healthy and balanced diet. The rapid degradation of nutritional and sensory quality during the processing and storage of a product is critical and plant-type-dependent. The introduction of disruptive technological solutions in fresh-cut processing, which could maintain fresh-like quality with less environmental impact, is an emerging research concept. The application of abiotic stress treatments (heat shock and UV-C) induces metabolic responses and microbial effects in plant tissues, potentially slowing down several quality senescence pathways. The previously selected combined and single effects of heat shock (100 °C/45 s; in the whole root) and UV-C (2.5 kJ/m2) treatments and two packaging conditions (oriented polypropylene (OPP) vs. micro-perforated OPP films) on controlling critical degradation pathways of fresh-cut carrots and on promoting bioactive and sensory quality during storage (5 °C, 14 days) were studied. Among the tested combinations, synergistic effects on the quality retention of fresh-cut carrots were only attained for applying heat shock associated with micro-perforated OPP film packaging. Its effects on reducing (3.3 Log10 CFU/g) the initial contamination and controlling microbiological spoilage (counts below the threshold limit of 7.5 Log10 CFU/g), increasing the bioactive content (38% and 72% in total phenolic content and chlorogenic acid, respectively), and preserving fresh quality attributes prove to be a viable alternative technology for shredded carrot processing.
- Effects of human-induced water level fluctuations on copepod assemblages of the littoral zone of Lake MaggiorePublication . Cifoni, Marco; Boggero, Angela; Rogora, Michela; Ciampittiello, Marzia; Martínez, Alejandro; Galassi, Diana Maria Paola; Fiasca, Barbara; Di Lorenzo, TizianaHuman-induced water level fluctuations (WLFs) are among the major pressures threatening lake ecosystems. Their effect on meiobenthic species of the littoral zone has been poorly investigated. In this study, we aimed at assessing the effects of human-induced WLFs on the composition and functionality of the benthic copepod assemblages of the littoral zone of Lake Maggiore, Italy and Switzerland. From 1942 to present, the water level of Lake Maggiore has been regulated through the Miorina Dam. We monitored copepod assemblages during different water levels defined within the period of regulation by the dam, using taxonomy- and trait-based metrics. We observed variation in the overall abundance and biomass of copepods, as well as in the number of individuals belonging to some trait classes such as ovigerous females, opportunists, omnivores and deposit feeders. None of the investigated trait class was completely lost. The results of our study suggest that ecosystem services supplied by the littoral zone of Lake Maggiore are likely altered by human-induced WLFs. Our findings provide a first picture of WLF impacts on benthic copepod assemblages, which can be useful for future research expanding on other functional traits.
- Context‐dependency in carnivore co‐occurrence across a multi‐use conservation landscapePublication . Curveira‐Santos, Gonçalo; Gigliotti, Laura; Sutherland, Chris; Rato, Daniela; Santos-Reis, Margarida; Swanepoel, Lourens H.Carnivore intraguild dynamics depend on a complex interplay of environmental affinities and interspecific interactions. Context-dependency is commonly expected with varying suites of interacting species and environmental conditions but seldom empirically described. In South Africa, decentralized approaches to conservation and the resulting multi-tenure conservation landscapes have markedly altered the environmental stage that shapes the structure of local carnivore assemblages. We explored assemblage-wide patterns of carnivore spatial (residual occupancy probability) and temporal (diel activity overlap) co-occurrence across three adjacent wildlife-oriented management contexts—a provincial protected area, a private ecotourism reserve, and commercial game ranches. We found that carnivores were generally distributed independently across space, but existing spatial dependencies were context-specific. Spatial overlap was most common in the protected area, where species occur at higher relative abundances, and in game ranches, where predator persecution presumably narrows the scope for spatial asymmetries. In the private reserve, spatial co-occurrence patterns were more heterogeneous but did not follow a dominance hierarchy associated with higher apex predator densities. Pair-specific variability suggests that subordinate carnivores may alternate between pre-emptive behavioral strategies and fine-scale co-occurrence with dominant competitors. Consistency in species-pairs diel activity asynchrony suggested that temporal overlap patterns in our study areas mostly depend on species' endogenous clock rather than the local context. Collectively, our research highlights the complexity and context-dependency of guild-level implications of current management and conservation paradigms; specifically, the unheeded potential for interventions to influence the local network of carnivore interactions with unknown population-level and cascading effects.