Harvesting Area (harvesting + area)

Distribution by Scientific Domains


Selected Abstracts


Modelling plumes of overland flow from logging tracks

HYDROLOGICAL PROCESSES, Issue 12 2002
P. B. Hairsine
Abstract Most land-based forestry systems use extensive networks of unsealed tracks to access the timber resource. These tracks are normally drained by constructing cross-banks, or water bars, across the tracks immediately following logging. Cross-banks serve three functions in controlling sediment movement within forestry compartments: 1.they define the specific catchment area of the snig track (also known as skid trails) so that the overland flow does not develop sufficient energy to cause gullies, and sheet and rill erosion is reduced; 2.they induce some sediment deposition as flow velocity reduces at the cross-bank; 3.they redirect overland flow into the adjacent general harvesting area (GHA) so that further sediment deposition may take place. This paper describes a simple model that predicts the third of these functions in which the rate of runoff from the track is combined with spatial attributes of the track and stream network. Predictions of the extent of the overland flow plumes and the volume of water delivered to streams is probabilistically presented for a range of rainfall-event scenarios with rainfall intensity, time since logging and compartment layout as model inputs. Generic equations guiding the trade-off between intercross-bank length and flow path distance from cross-bank outlet to the stream network needed for infiltration of track runoff are derived. Copyright © 2002 John Wiley & Sons, Ltd. Copyright © 2002 John Wiley & Sons, Ltd. [source]


The response of Phragmites australis to harvesting pressure in the Muzi Swamp of the Tembe Elephant Park, South Africa

LAND DEGRADATION AND DEVELOPMENT, Issue 5 2004
J. A. Tarr
Abstract Phragmites australis (Cav.) Trin. ex Steud. has been harvested in the Muzi Swamp in Maputaland, South Africa for generations. Over the last ten years, however, a flourishing trade in this reed has developed. Concern has now been expressed that at the current levels of utilization the ecological integrity of the Muzi Swamp is being compromised, and that the current harvesting rates are not sustainable in the long term. The hypothesis was put forward that a degradation gradient exists with the most severe degradation occurring the closest to where community members enter the park, and the least degradation the furthest from this point. The results of this study, however, show no distinct degradation gradient. Yet the overall condition of the reeds in the harvesting area is poorer than in the non-utilized area. Expansion of the current harvesting area, coupled with adaptive harvesting systems and yearly monitoring will improve the quality of the reeds within the harvesting area without affecting the harvesting quotas. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Parental relationships among three grape varieties studied by MALDI of grape seed protein profiles,

JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 9 2010
Antonella Bertazzo
Abstract Two Raboso cultivars, i.e. Raboso Veronese and Raboso Piave, are two black Vitis vinifera varieties. A genetic study suggested that Raboso Veronese is the progeny of a spontaneous cross between Raboso Piave and Marzemina Bianca cultivars. Parental relationships are usually investigated by genetic studies, which are effective to establish genetic links among different cultivars. Considering that proteome is the genome expression, in this article we evaluated the power of seed protein profiles obtained by matrix-assisted laser desorption/ionization (MALDI)/MS for parentage investigation. The three cultivars lead to very similar spectra with differences in the relative intensity of the most abundant species and the presence of very weak specific ions. In order to evaluate the analytical significance of these aspects, the variability due to instrumental factors and due to different harvesting areas and years of the same cultivars have been considered and measured by the calculation of discrepancy factor values. On one hand, the results obtained can be considered a valid confirmation of the genomic findings, whereas on the other hand, the results provide evidence for the ability of MALDI/MS to individuate minor differences in protein profiles of complex protein mixtures. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Measurement and analysis of truck transport vibration levels and damage to packaged tangerines during transit

PACKAGING TECHNOLOGY AND SCIENCE, Issue 4 2005
Bundit Jarimopas
Abstract The purpose of this study was to measure the vibration levels in commercial truck shipments in Thailand and observe the effects on packaged fruit. The study measured the vibration levels in two of the most commonly used truck types to ship packaged goods as a function of road condition and vehicle speed. The suspension type on the trailers studied was leaf-spring. The results of damage to packaged tangerine fruit as a function of location in the payload are also presented. The data presented in this study will assist product and package designers to reduce damage in transit. The results showed that vibration levels increased with speed and as a result of road condition. Analysis of variance indicated that three controlling factors, road surface, truck speed and truck type, significantly affected (p , 0.05) peak PSD, PSD* (root mean square) over the frequency range 2,5,Hz, and fruit damage. As expected, based on previous work, an increase in truck speed resulted in an increase in vibration levels and damage to packaged fruit. The laterite road condition produced the highest vibration level for a given truck and travelling speed followed by concrete highway and asphalt road conditions. Fruit damage was found to be greatest in the uppermost container for every combination of road, truck type and travelling speed, which also corresponded to the highest vibration levels recorded. The results showed that a significant amount of damage can occur on unpaved roads (laterite), while the packages are transported from farms and harvesting areas to regional truck terminals. Damage on asphalt road conditions was minimal. This paper provides an updated history of measured and quantified levels of vibration for these specific trucks and road conditions. Copyright © 2005 John Wiley & Sons, Ltd. [source]