scholarly journals Vehicle Routeing with Multiple Use of Vehicles

1996 ◽  
Vol 47 (8) ◽  
pp. 1065 ◽  
Author(s):  
Eric D. Taillard ◽  
Gilbert Laporte ◽  
Michel Gendreau
1996 ◽  
Vol 47 (8) ◽  
pp. 1065-1070 ◽  
Author(s):  
Éric D. Taillard ◽  
Gilbert Laporte ◽  
Michel Gendreau

2019 ◽  
Vol 18 (2) ◽  
pp. 177-184 ◽  
Author(s):  
Min-jin Kim ◽  
Sang-su An ◽  
Min-cheol Cho ◽  
Se-il Park ◽  
Jong-min Kim ◽  
...  

1994 ◽  
Vol 59 ◽  
Author(s):  
N. Lust

A  successful and justified multiannual afforestation programme requires a good  insight into the objectives and awareness of the constraints of the new  forests, a planning strategy and a thorough research on the missing aspects.      Socio-economic constraints mainly relate to social aspects of the farmers  involved, who must be assured of a viable income.     Therefore the new forest types and silvicultural systems should produce a  reasonable return, without neglecting however the global multiple use  objective.     Planning has to deal with specific goals, the area of new forests, the  location and size, accompanying measures and a time scale.


2021 ◽  
Vol 13 (3) ◽  
pp. 458
Author(s):  
Sol Milne ◽  
Julien G. A. Martin ◽  
Glen Reynolds ◽  
Charles S. Vairappan ◽  
Eleanor M. Slade ◽  
...  

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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