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Pablo M. Vergara Luis O. Meneses Audrey A. Grez Madelaine S. Quiroz Gerardo E. Soto Christian G. Pérez-Hernández Paola A. Diaz Ingo J. Hahn Andrés Fierro 《Landscape Ecology》2017,32(2):279-293
Context
Interactions between landscape-scale processes and fine-grained habitat heterogeneity are usually invoked to explain species occupancy in fragmented landscapes. In variegated landscapes, however, organisms face continuous variation in micro-habitat features, which makes necessary to consider ecologically meaningful estimates of habitat quality at different spatial scales.Objectives
We evaluated the spatial scales at which forest cover and tree quality make the greatest contribution to the occupancy of the long-horned beetle Microplophorus magellanicus (Coleoptera: Cerambycidae) in a variegated forest landscape.Methods
We used averaged data of tree quality (as derived from remote sensing estimates of the decay stage of single trees) and spatially independent pheromone-baited traps to model the occurrence probability as a function of multiple cross-scale combinations between forest cover and tree quality (with scales ranging between 50 and 400 m).Results
Model support and performance increased monotonically with the increasing scale at which tree quality was measured. Forest cover was not significant, and did not exhibit scale-specific effects on the occurrence probability of M. magellanicus. The interactive effect between tree quality and forest cover was stronger than the independent (additive) effects of tree quality and particularly forest cover. Significant interactions included tree quality measured at spatial scales ≥200 m, but cross-scale interactions occurred only in four of the seven best-supported models.Conclusions
M. magellanicus respond to the high-quality trees available in the landscape rather than to the amount of forest per se. Conservation of viable metapopulations of M. magellanicus should consider the quality of trees at spatial scales >200 m.2.
Organic amendments, such as bokashi, are applied to the soil to increase the N. However, the available N provided by these fertilizers and the feedstocks with which they are produced have been poorly documented. In this work, the available N in bokashi was evaluated as well as their biological stability and chemical maturity. The treatments bokashi poultry (WVP); bokashi swine (WVS) and bokashi control (WVC) contained wheat straw and vegetable wastes; WVP and WVS also included poultry and swine manure, respectively. The temperature, mineral N, pH, EC, CO2 production rate and germination index (IG) were measured. At the end of the trial, all of the treatments’ temperatures exceeded room temperature. The WVP presented a higher mineral N (1,054 mg kg?1) than the WVS (844 mg kg?1) and the WVC (907 mg kg?1). In all treatments, the NH4+ and NO3? decreased. EC reached phytotoxicity levels in all treatments (EC > 3 dS m?1). None of the treatments showed biological stability or chemical maturity (IG of WVP, WVS and WVC: 10%, 29% and 19%, respectively). Therefore, it is concluded that applying these bokashi to soils could limit crop growth due to phytotoxic effects and immobilization of transient N. 相似文献
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The photochemical transformation of SO2 and the generation of aerosol particles are investigated in a variety of atmospheres, with and without initial aerosols, in clean and polluted air, and with various pollutants. The pollutants in addition to the SO2 include O3, NO, NO2 and water vapor in a variety of combinations. The most striking finding is, that only with the combination of SO2, NO2, and H2O is the aerosol particle production large. 相似文献
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Vergara Pablo M. Soto Gerardo E. Rodewald Amanda D. Quiroz Madelaine 《Landscape Ecology》2019,34(1):79-92
Context
The switching pattern between behavioral modes provides a mechanistic basis for understanding how animals perceive and memorize the habitat quality in their home ranges.
ObjectivesWe assessed if Magellanic woodpeckers (Campephilus magellanicus) move based on habitat quality at local (neighboring trees) and home range scales.
MethodsWe used state-space models to examine the relationship between remotely-sensed estimates of habitat quality (tree decay) and movement of adult woodpeckers tracked with GPS telemetry in southern Chile.
ResultsWoodpeckers spent most time (>?80%) in the area-restricted search (ARS) mode in contrast to the exploratory transient mode, characterized by frequent directional displacements (>?50 m). The extent to which individuals switched between behavioral modes was related to habitat quality at different scales. Woodpeckers switched to and remained in the ARS mode when encountering moderate levels of heterogeneity in habitat quality. At very low or high heterogeneity levels, however, individuals switched to and remained in the transient mode, respectively. Likewise, as habitat quality declined locally and across home range, woodpeckers were more likely to adopt a transient mode.
ConclusionsAlthough woodpeckers seemed to easily perceive and memorize habitat quality at different spatial scales, our results suggest that spatial memory will less effective under extreme levels of habitat heterogeneity.
相似文献7.
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Osama G. Mohamed Sadaf Dorandish Rebecca Lindow Megan Steltz Ifrah Shoukat Maira Shoukat Hussein Chehade Sara Baghdadi Madelaine McAlister-Raeburn Asad Kamal Dawit Abebe Khaled Ali Chelsey Ivy Maria Antonova Pamela Schultz Michael Angell Daniel Clemans Timothy Friebe David Sherman Anne M. Casper Paul A. Price Ashootosh Tripathi 《Marine drugs》2021,19(8)
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Cécile Madelaine Eric Malézieux Nicole Sibelet Raphaël J. Manlay 《Agroforestry Systems》2008,73(3):189-204
In West Africa, natural regeneration of oil palms (Elaeis guineensis Jacq.) can be favoured by agricultural practices. The structure of palm groves may thus reflect the history of land use.
In this study, we examined the connection between biophysical factors, land use and the structure and dynamics of semi-wild
palm groves in the village of Nienh, in the forest region of Guinea (Forest Guinea), in order to determine to what extent
semi-wild palm groves could be considered as an ecological indicator of the history of regional landscapes. Grove management
strategies of farmers were also determined and related to farm characteristics. In Nienh, semi-wild palm groves were found
in three cropping systems with differing characteristics in each. Palms were scarce in lowland agricultural areas (8 palms ha−1), while they were significantly taller (15.8 m on average) and less dense (36 palms ha−1) in agroforests than in slash-and-burn cropping systems (9.4 m and 55 palms ha−1 respectively). Interviews with farmers showed that it was possible for a farmer to have a global strategy of semi-wild palm
grove densification combined with oil palm elimination on a plot scale. The lack of regeneration of palms in agroforests resulted
from the almost systematic elimination of young palms by farmers. Conversely, in slash-and-burn cropping systems, young palms
were often preserved. As the structure of semi-wild palm groves was partly explained by agricultural practices, it could be
used as an ecological indicator of changes in practice in relation to socio-economic context. 相似文献