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J Humphreys - One of the best experts on this subject based on the ideXlab platform.

  • the effects of treading by two breeds of dairy cow with different live weights on Soil physical properties poaching Damage and herbage production on a poorly drained clay loam Soil
    The Journal of Agricultural Science, 2015
    Co-Authors: P Tuohy, N M Holden, Owen Fenton, J Humphreys
    Abstract:

    There is little empirical evidence to indicate that dairy cow live weight affects the extent of Soil Damage at the hoof-Soil interface during grazing on poorly drained permanent grassland. In the present study the impact of Holstein-Friesian (HF) dairy cows with a mean (±standard deviation) live weight of 570 (±61) kg were compared with Jersey × Holstein-Friesian (JX) with a mean live weight of 499 (±52) kg each at two stocking densities: mean 2·42 ± (0·062) and 2·66 (±0·079) cows/ha. Soil physical properties (bulk density, macroporosity, gravimetric water content, air-filled porosity, penetration resistance and shear strength), poaching Damage (post-grazing Soil surface deformation and hoof-print depth), herbage yield and milk production were measured throughout 2011 and 2012. Soil physical properties, post-grazing Soil surface deformation and herbage production were not affected by dairy cow breed or by interactions between breed and stocking density. Hoof-print depth was higher in the HF treatments (39 v. 37 mm, s.e. 0·5 mm). Loading pressure imposed at the Soil surface was the same for both breeds due to a direct correlation between live weight and hoof size. Poaching Damage was greater at higher stocking density. Using the lighter JX cow offered little advantage in terms of lowering the negative impact of treading on Soil physical properties or reducing poaching Damage and no advantage in terms of herbage or milk production compared with the heavier HF cow.

Holopainen Markus - One of the best experts on this subject based on the ideXlab platform.

  • Airborne LiDAR-derived elevation data in terrain trafficability mapping
    'Informa UK Limited', 2017
    Co-Authors: Niemi, Mikko T., Vastaranta Mikko, Vauhkonen Jari, Melkas Timo, Holopainen Markus
    Abstract:

    Heavy off-road traffic causes Soil compaction and rutting, which can significantly reduce the yield of forest stands. Reliable information on terrain trafficability, that is, the ability of terrain to support the passage of vehicles, would enable significant enhancement of wood procurement planning and reduction of Soil Damage. The objective here was to determine the feasibility of airborne scanning light detection and ranging (LiDAR)-derived digital terrain models (DTM) in terrain trafficability mapping. Soil Damage was inventoried from a total of 13 km of forwarding trails, and a logistic regression model was fitted for predicting the event of Soil Damage. DTM-derived Soil wetness indices performed well as predictor variables, and DTM-derived local binary patterns also proved useful in terrain trafficability mapping. A prediction accuracy of 83.6% (Cohen’s kappa of 0.38) was observed for Soil Damage probability modelling, using only DTM-derived predictors, and a corresponding accuracy of 85.0% (kappa of 0.45) was achieved when an existing Soil map was used as well. In addition to the topography-related features, Soil stoniness proved to be a critical factor affecting Soil resistance to rutting. Our results indicate that the utilisation of LiDAR-derived elevation data for terrain trafficability mapping is a feasible method in sustainable forest management.201

Markus Holopainen - One of the best experts on this subject based on the ideXlab platform.

  • airborne lidar derived elevation data in terrain trafficability mapping
    Scandinavian Journal of Forest Research, 2017
    Co-Authors: Mikko Niemi, Mikko Vastaranta, Jari Vauhkonen, Timo Melkas, Markus Holopainen
    Abstract:

    ABSTRACTHeavy off-road traffic causes Soil compaction and rutting, which can significantly reduce the yield of forest stands. Reliable information on terrain trafficability, that is, the ability of terrain to support the passage of vehicles, would enable significant enhancement of wood procurement planning and reduction of Soil Damage. The objective here was to determine the feasibility of airborne scanning light detection and ranging (LiDAR)-derived digital terrain models (DTM) in terrain trafficability mapping. Soil Damage was inventoried from a total of 13 km of forwarding trails, and a logistic regression model was fitted for predicting the event of Soil Damage. DTM-derived Soil wetness indices performed well as predictor variables, and DTM-derived local binary patterns also proved useful in terrain trafficability mapping. A prediction accuracy of 83.6% (Cohen’s kappa of 0.38) was observed for Soil Damage probability modelling, using only DTM-derived predictors, and a corresponding accuracy of 85.0% (...

Ciaran Nugent - One of the best experts on this subject based on the ideXlab platform.

  • characteristic site disturbance due to harvesting and extraction machinery traffic on sensitive forest sites with peat Soils
    Forest Ecology and Management, 2003
    Co-Authors: Ciaran Nugent, Christopher Kanali, Philip Owende, Martin Nieuwenhuis, S M Ward
    Abstract:

    Abstract The effects of wood harvesting and extraction machinery traffic on sensitive forest sites with peat Soils were characterised with the objective of quantifying the threshold levels beyond which significant site impacts (compaction and rutting) would occur. The treatments involved running the machines in selected extraction racks (i.e., 3 m wide machine routes) while conducting normal wood thinning and extraction operations comprising one and two passes by the harvester and the forwarder with full payload, respectively. Soil disturbance thresholds were established by testing the level of significance of the difference in induced Soil Damage and compaction before and after machine traffic treatments. For volumetric Soil water content lying between 10.0 and 14.9%, threshold cone penetration resistance levels for two 600/55–30.5 tyres were found to range from 594 to 640 kPa for deep-raised peat Soil with initial strength lying between 524 and 581 kPa. In general, the proportion of the total rut depth data in each rack that exceeded the threshold level of 21.5 cm was about 5%. The threshold value corresponds to sinkage equivalent to 15% of the overall wheel diameter of the harvester, above which machine mobility would be hampered considerably. In addition, after harvester traffic the mean rut depth per unit rack length was 10.2×10 −2  cm/m, and it ranged from 0.7 to 24.7×10 −2  cm/m.

A Dupeyrat - One of the best experts on this subject based on the ideXlab platform.

  • effects of commercial timber harvesting on streamflow regimes in the plynlimon catchments mid wales
    Hydrological Processes, 2005
    Co-Authors: M Robinson, A Dupeyrat
    Abstract:

    This paper presents the first large-scale British study of the impacts of commercial forest cutting on stream-flow regimes. The 70% forested headwaters of the River Severn are part of the intensively instrumented long-term Plynlimon catchment study into the impact of land use on stream flow. The forest area, comprising predominantly Sitka spruce (Picea sitchensis), was planted mainly in the 1930s and 1940s. Harvesting commenced in the mid-1980s and over the study period about half the forest has been felled. Changes in annual water yield and extreme flows were studied in four nested catchments ranging in area from about 1 to 10 km2 and compared with an adjacent benchmark grassland catchment. As expected from earlier process studies the cutting of the forest increased total annual flows. Less expected was the clear evidence that the felling augmented low flows. This informs a long-standing debate whether upland forestry increases or reduces baseflows. A particularly notable result was the lack of impact of the harvesting on storm peak flows. This may result from the application of forest management guidelines designed to reduce Soil Damage and erosion during the harvesting, and indicates that the forest itself has a limited impact on flooding. These findings are timely because British forest expansion peaked in the 30 years following the Second World War, and large areas of these woodlands are now approaching economic maturity and will be harvested in the next two decades. Copyright © 2004 John Wiley & Sons, Ltd.