Exorcising Malthusian ghosts: Vaccinating the Nexus to advance integrated water, energy and food resource resilience

The current work investigates dietary overlap and food partitioning among nine abundant carnivorous fishes caught in the shallow waters of the Paraíba do Norte river estuary, Paraíba State, Brazil. Fishes were sampled with a beach seine net between January and December 2008 and a total of 958 specimens had their stomach content analyzed. Crustacea was the dominant food resource for Lutjanus alexandrei, L. jocu and Bathygobius soporator, whereas Telostei were consumed mainly by Centropomus undecimalis and C. parallelus. In contrast, Polychaeta were preyed upon mainly by Diapterus rhombeus, Eucinostomus argenteus, Sciades herzbergii and S. parkeri. Although most species consumed similar food items, they did that in varying proportions and amounts. Overall, the niche overlap among species was low (< 0.60), but there were several cases where pair of species had their feeding niche highly overlapped (between 0.72 and 0.97). These findings corroborate the hypothesis that food resource partitioning determines species coexistence in estuarine tropical environments.

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Improved Glucose Recovery from Sicyos angulatus by NaOH Pretreatment and Application to Bioethanol Production

Processes ◽

10.3390/pr9020245 ◽

2021 ◽

Vol 9 (2) ◽

pp. 245

Author(s):

Hyung-Eun An ◽

Kang Hyun Lee ◽

Ye Won Jang ◽

Chang-Bae Kim ◽

Hah Young Yoo

Keyword(s):

Saccharomyces Cerevisiae ◽

Alternative Energy ◽

Invasive Plant ◽

Food Resource ◽

Raw Material ◽

Control Group ◽

Bioethanol Production ◽

Naoh Pretreatment ◽

Glucose Recovery ◽

Harmful Species

As greenhouse gases and environmental pollution become serious, the demand for alternative energy such as bioethanol has rapidly increased, and a large supply of biomass is required for bioenergy production. Lignocellulosic biomass is the most abundant on the planet and a large part of it, the second-generation biomass, has the advantage of not being a food resource. In this study, Sicyos angulatus, known as an invasive plant (harmful) species, was used as a raw material for bioethanol production. In order to improve enzymatic hydrolysis, S. angulatus was pretreated with different NaOH concentration at 121 °C for 10 min. The optimal NaOH concentration for the pretreatment was determined to be 2% (w/w), and the glucan content (GC) and enzymatic digestibility (ED) were 46.7% and 55.3%, respectively. Through NaOH pretreatment, the GC and ED of S. angulatus were improved by 2.4-fold and 2.5-fold, respectively, compared to the control (untreated S. angulatus). The hydrolysates from S. angulatus were applied to a medium for bioethanol fermentation of Saccharomyces cerevisiae K35. Finally, the maximum ethanol production was found to be 41.3 g based on 1000 g S. angulatus, which was 2.4-fold improved than the control group.

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Prescribed burning in a mediterranean-climate region mitigates the disturbance by bushfire to a critical food resource for an endangered bird, the Carnaby’s cockatoo

Fire Ecology ◽

10.1186/s42408-019-0054-8 ◽

2019 ◽

Vol 15 (1) ◽

Cited By ~ 1

Author(s):

Valerie S. Densmore ◽

Emma S. Clingan

Keyword(s):

Seed Production ◽

Prescribed Burning ◽

Fire Regime ◽

Fire Hazard ◽

Food Resource ◽

Management Tool ◽

Fire Intensity ◽

Prescribed Burns ◽

Low Intensity ◽

Percentage Survival

Abstract Background Prescribed burning is used to reduce fire hazard in highly flammable vegetation types, including Banksia L.f. woodland that occurs on the Swan Coastal Plain (SCP), Western Australia, Australia. The 2016 census recorded well over 1.9 million people living on the SCP, which also encompasses Perth, the fourth largest city in Australia. Banksia woodland is prone to frequent ignitions that can cause extensive bushfires that consume canopy-stored banksia seeds, a critical food resource for an endangered bird, the Carnaby’s cockatoo (Calyptorynchus latirostris, Carnaby 1948). The time needed for banksias to reach maturity and maximum seed production is several years longer than the typical interval between prescribed burns. We compared prescribed burns to bushfires and unburned sites at three locations in banksia woodland to determine whether low-intensity prescribed burns affect the number of adult banksias and their seed production. Study sites were matched to the same vegetation complex, fire regime, and time-since-fire to isolate fire intensity as a variable. Results Headfire rates of spread and differenced normalized burn ratios indicated that prescribed burning was generally of a much lower intensity than bushfire. The percentage survival of adult banksias and their production of cones and follicles (seeds) did not decrease during the first three years following a prescribed burn. However, survival and seed production were significantly diminished followed high-intensity bushfire. Thus, carrying capacity for Carnaby’s cockatoo was unchanged by prescribed burning but decreased markedly following bushfire in banksia woodland. Conclusions These results suggest that prescribed burning is markedly different from bushfire when considering appropriate fire intervals to conserve canopy habitats in fire-resilient vegetation communities. Therefore, low-intensity prescribed burning represents a viable management tool to reduce the frequency and extent of bushfire impacts on banksia woodland and Carnaby’s cockatoo.

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Drivers of Bornean Orangutan Distribution across a Multiple-Use Tropical Landscape

Remote Sensing ◽

10.3390/rs13030458 ◽

2021 ◽

Vol 13 (3) ◽

pp. 458

Author(s):

Sol Milne ◽

Julien G. A. Martin ◽

Glen Reynolds ◽

Charles S. Vairappan ◽

Eleanor M. Slade ◽

...

Keyword(s):

Forest Cover ◽

Food Resource ◽

Multiple Use ◽

Natural Forests ◽

Bornean Orangutan ◽

Aerial Surveys ◽

Significant Difference ◽

The Difference ◽

Fig Trees ◽

Abundance And Distribution

Logging and conversion of tropical forests in Southeast Asia have resulted in the expansion of landscapes containing a mosaic of habitats that may vary in their ability to sustain local biodiversity. However, the complexity of these landscapes makes it difficult to assess abundance and distribution of some species using ground-based surveys alone. Here, we deployed a combination of ground-transects and aerial surveys to determine drivers of the critically endangered Bornean Orangutan (Pongo pygmaeus morio) distribution across a large multiple-use landscape in Sabah, Malaysian Borneo. Ground-transects and aerial surveys using drones were conducted for orangutan nests and hemi-epiphytic strangler fig trees (Ficus spp.) (an important food resource) in 48 survey areas across 76 km2, within a study landscape of 261 km2. Orangutan nest count data were fitted to models accounting for variation in land use, above-ground carbon density (ACD, a surrogate for forest quality), strangler fig density, and elevation (between 117 and 675 m). Orangutan nest counts were significantly higher in all land uses possessing natural forest cover, regardless of degradation status, than in monoculture plantations. Within these natural forests, nest counts increased with higher ACD and strangler fig density, but not with elevation. In logged forest (ACD 14–150 Mg ha−1), strangler fig density had a significant, positive relationship with orangutan nest counts, but this relationship disappeared in a forest with higher carbon content (ACD 150–209 Mg ha−1). Based on an area-to-area comparison, orangutan nest counts from ground transects were higher than from counts derived from aerial surveys, but this did not constitute a statistically significant difference. Although the difference in nest counts was not significantly different, this analysis indicates that both methods under-sample the total number of nests present within a given area. Aerial surveys are, therefore, a useful method for assessing the orangutan habitat use over large areas. However, the under-estimation of nest counts by both methods suggests that a small number of ground surveys should be retained in future surveys using this technique, particularly in areas with dense understory vegetation. This study shows that even highly degraded forests may be a suitable orangutan habitat as long as strangler fig trees remain intact after areas of forest are logged. Enrichment planting of strangler figs may, therefore, be a valuable tool for orangutan conservation in these landscapes.

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Movement syndromes of a Neotropical frugivorous bat inhabiting heterogeneous landscapes in Brazil

Movement Ecology ◽

10.1186/s40462-021-00266-6 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Patricia Kerches-Rogeri ◽

Danielle Leal Ramos ◽

Jukka Siren ◽

Beatriz de Oliveira Teles ◽

Rafael Souza Cruz Alves ◽

...

Keyword(s):

Site Fidelity ◽

Animal Movement ◽

Radio Telemetry ◽

Food Resource ◽

Movement Behavior ◽

Movement Activity ◽

Landscape Features ◽

Heterogeneous Landscapes ◽

Movement Data ◽

High Site

Abstract Background There is growing evidence that individuals within populations can vary in both habitat use and movement behavior, but it is still not clear how these two relate to each other. The aim of this study was to test if and how individual bats in a Stunira lilium population differ in their movement activity and preferences for landscape features in a correlated manner. Methods We collected data on movements of 27 individuals using radio telemetry. We fitted a heterogeneous-space diffusion model to the movement data in order to evaluate signals of movement variation among individuals. Results S. lilium individuals generally preferred open habitat with Solanum fruits, regularly switched between forest and open areas, and showed high site fidelity. Movement variation among individuals could be summarized in four movement syndromes: (1) average individuals, (2) forest specialists, (3) explorers which prefer Piper, and (4) open area specialists which prefer Solanum and Cecropia. Conclusions Individual preferences for landscape features plus food resource and movement activity were correlated, resulting in different movement syndromes. Individual variation in preferences for landscape elements and food resources highlight the importance of incorporating explicitly the interaction between landscape structure and individual heterogeneity in descriptions of animal movement.

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The Influence of Fear Effect to a Discrete-Time Predator-Prey System with Predator Has Other Food Resource

Mathematics ◽

10.3390/math9080865 ◽

2021 ◽

Vol 9 (8) ◽

pp. 865

Author(s):

Jialin Chen ◽

Xiaqing He ◽

Fengde Chen

Keyword(s):

Discrete Time ◽

Food Resource ◽

Sufficient Conditions ◽

Iteration Scheme ◽

Predator Species ◽

Predator Prey ◽

Interior Equilibrium ◽

Fear Effect ◽

Prey System ◽

Trivial Equilibrium

A discrete-time predator–prey system incorporating fear effect of the prey with the predator has other food resource is proposed in this paper. The trivial equilibrium and the predator free equilibrium are both unstable. A set of sufficient conditions for the global attractivity of prey free equilibrium and interior equilibrium are established by using iteration scheme and the comparison principle of difference equations. Our study shows that due to the fear of predation, the prey species will be driven to extinction while the predator species tends to be stable since it has other food resource, i.e., the prey free equilibrium may be globally stable under some suitable conditions. Numeric simulations are provided to illustrate the feasibility of the main results.

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Predicting the Future Distribution of Ara rubrogenys, an Endemic Endangered Bird Species of the Andes, Taking into Account Trophic Interactions

Diversity ◽

10.3390/d13020094 ◽

2021 ◽

Vol 13 (2) ◽

pp. 94

Author(s):

Alain Hambuckers ◽

Simon de Harenne ◽

Eberth Rocha Ledezma ◽

Lilian Zúñiga Zeballos ◽

Louis François

Keyword(s):

Food Resource ◽

Bird Species ◽

Co2 Concentration ◽

Distribution Models ◽

Plant Resources ◽

Term Survival ◽

The Andes ◽

Vegetation Models ◽

Fertilizing Effect ◽

The Impact

Species distribution models (SDMs) are commonly used with climate only to predict animal distribution changes. This approach however neglects the evolution of other components of the niche, like food resource availability. SDMs are also commonly used with plants. This also suffers limitations, notably an inability to capture the fertilizing effect of the rising CO2 concentration strengthening resilience to water stress. Alternatively, process-based dynamic vegetation models (DVMs) respond to CO2 concentration. To test the impact of the plant modelling method to model plant resources of animals, we studied the distribution of a Bolivian macaw, assuming that, under future climate, DVMs produce more conservative results than SDMs. We modelled the bird with an SDM driven by climate. For the plant, we used SDMs or a DVM. Under future climates, the macaw SDM showed increased probabilities of presence over the area of distribution and connected range extensions. For plants, SDMs did not forecast overall response. By contrast, the DVM produced increases of productivity, occupancy and diversity, also towards higher altitudes. The results offered positive perspectives for the macaw, more optimistic with the DVM than with the SDMs, than initially assumed. Nevertheless, major common threats remain, challenging the short-term survival of the macaw.

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The dark side of rocks: an underestimated high‐quality food resource in river ecosystems

Journal of Ecology ◽

10.1111/1365-2745.13647 ◽

2021 ◽

Author(s):

Fen Guo ◽

Stuart E. Bunn ◽

Michael T. Brett ◽

Hannes Hager ◽

Martin J. Kainz

Keyword(s):

Food Resource ◽

Dark Side ◽

High Quality ◽

River Ecosystems ◽

Quality Food

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