Logging Roads Research Articles

Сезонное промерзание лесовозной грунтовой дороги: моделирование условий появления поперечных трещин

Сезонное промерзание лесовозной грунтовой дороги: моделирование условий появления поперечных трещин

Impacts of modern mechanised skidding on the natural and cultural heritage of the Polish Carpathian Mountains

Abstract The aim of the research was to determine the scale and forms of logging road impacts on the natural environment and residual cultural heritage of Ruthenian Highlanders that characterise the Polish part of the north-eastern Carpathians. To this end, we used LiDAR-derived DEM to detect and map forest roads and skid trails, and to estimate road density, in 60 forest divisions sampled at random from among the 2639 km2 of forest managed in the above region by the State Forests National Forest Holding. The determined road network was then validated by GPS ground control. Supplementary, detailed LiDAR data were used to detect features of the past cultural landscape, and to determine the interference in that due to contemporary logging roads. Overall skidder traffic was estimated on the basis of a thorough analysis of State Forests documents, including legal acts, guidelines, management plans, detailed databases and maps of planned cuts. LiDAR data proved to be an adequate tool in the mapping of the network of logging roads present under the tree canopy, although it slightly underestimates road density in a densely vegetated, post-landslide topography. Our LiDAR-assessed density of Carpathian logging roads (at 108.5–140.7 m ha−1, including skid trails) is nevertheless among the highest reported in the literature, and one that far exceeds recommended values. Spatial pattern analysis further revealed the unfavourable phenomenon of multiple parallel roads forming contiguous areas of disturbed soil and constituting dispersal paths for invasive plants. Many examples of cultural remains being run over and destroyed by skidders could also be reported. The observed process of log extraction is one of the least sustainable aspects to forest management in the Carpathians, and our results emphasise very clearly the need for rules to support the preservation of cultural heritage in forested areas, as well as improved tools by which skidding practices can be monitored.

LOGGING ROADS IN TROPICAL FORESTS: SYNTHESIS OF LITERATURE WRITTEN IN FRENCH AND ENGLISH HIGHLIGHTS ENVIRONMENTAL IMPACT REDUCTION THROUGH IMPROVED ENGINEERING

Les pistes forestières sont considérées comme des causes majeures de dégrada- tion des forêts en raison de leurs impacts directs et indirects sur le fonctionnement et la diversité des écosystèmes. Compte tenu de l’importance de l’exploitation forestière tropi- cale dans le monde, la bonne gestion de l’in- frastructure routière est cruciale pour réduire les impacts environnementaux associés à ces activités tout en réduisant les coûts des opé- rations. Notre étude visait à analyser comment la question des pistes de débardage avait été traitée dans la littérature scientifique. Des études publiées depuis 65 ans, la plupart en français, dans la revue Bois et Forêts des Tro- piques (BFT), ont été comparées à une série d’études plus récentes extraites des bases de données Scopus et Web of Knowledge. La moitié des articles BFT datent d’avant 1972, alors que les bases de données plus géné- ralistes indiquent une augmentation régu- lière, depuis cette date, du nombre d’articles publiés sur ce thème, qui atteint aujourd’hui un niveau record. Sur l’ensemble de la biblio- graphie, nous avons sélectionné, à des fins d’évaluation critique, 126 articles traitant des impacts et de la gestion des pistes forestières tropicales. Les articles de BFT se caractérisent par une attention particulière portée à des questions pratiques d’ingénierie, tandis que de nombreux articles rédigés en anglais se concentrent sur l’identification des impacts sur les écosystèmes forestiers. Les impacts environnementaux liés aux pistes forestières proviennent de la destruction du couvert pen- dant leur construction, de l’accroissement des effets de lisière, de l’érosion des sols, de la perturbation de la faune et de l’accès plus facile aux forêts pour la chasse et la colonisa- tion agricole. Nous présentons, sur la base de cette revue de la littérature, une liste de recommandations permettant de réduire ces impacts. En conclusion, nous constatons, que malgré l’intérêt continu pour le sujet des pistes forestières, nous savons très peu de choses sur leur devenir à long terme dans les paysages forestiers.

LA QUESTION DE L'IMPACT DES PISTES D'EXPLOITATION FORESTIÈRE

Dans le langage commun, les pistes forestières sont syno- nymes de fragmentation, de couloirs d’accès aux popula- tions humaines ou aux espèces invasives, voire plus sim- plement d’atteintes à l’intégrité de zones restées jusque-là à peu près intactes. Est-ce si simple cependant ? De quoi sont directement responsables les pistes forestières en milieu tropical ? Et leurs impacts demeurent-ils réellement irréversibles ? Dans ce numéro 328 de Bois et Forêts des Tro- piques, nous proposons deux articles de synthèse qui, sans prétendre faire le tour de telles questions, apportent toute- fois de très intéressants éléments de réponse...

Anthropogenic influences on the distribution of a Vulnerable coniferous forest specialist: habitat selection by the Siberian musk deerMoschus moschiferus

AbstractThe Siberian musk deerMoschus moschiferus, categorized as Vulnerable on the IUCN Red List, is a small ungulate associated with coniferous forests of East Asia. In Russia the species is hunted both legally and illegally for the commercially valuable musk gland in males. Steep population declines recorded in recent decades have been generally attributed to intensive illegal hunting, but the decline has coincided with increased logging activity and the concomitant expansion of logging roads. We conducted an occupancy analysis in Primorskii Krai, Russia, to elucidate the relative importance of environmental, ecological and anthropogenic features associated with the presence of musk deer. The top model contained covariates related to the abundance of bearded lichenUsneaspp., the distance to a main road and the distance to logging sites, suggesting that both intensive hunting of musk deer (associated with greater accessibility via roads) and logging of habitat are influencing the occurrence of this species. We propose several management actions to limit the negative influence of logging and logging roads on musk deer in Russia, including encouraging logging companies to set aside high conservation value forests (to retain intact forests) and to close logging roads post-harvest (to reduce access by poachers).

Обоснование применения каменных материалов при строительстве оснований и покрытий лесовозных автомобильных дорог

Justification of stone in construction materials bases and covers logging roads. These changes depending on the strength of stone material particles relative to the coordination number and change the contact forces between the particles when subjected to repeated cyclic loads. It was established that the limestone rubble strength of 400 is much more prone to crushing when the effects of multiple cyclic loads than solid dolomite and granite rub-ble. The increase in the restraining force between the particles due to the weak cementing stone materials ranged from 5 to 30 percent.

An estimation of soil loss from tractor logging roads : The estimation of soil erodibility factor for Universal Soil Loss Equation

An estimation of soil loss from tractor logging roads : The estimation of soil erodibility factor for Universal Soil Loss Equation

Algorithm for solving the problem of optimal tracing of a timber road on a non-uniform terrain

The tracing of individual logging roads is part of a more general task - the development of a scheme for transport development of the enterprise's forest raw material base. As a result of its solution, the location of the main transport routes - highways and branches - is determined in the forest, taking into account the optimal distances between the branches. When establishing these distances, account is taken of the costs of forest management measures, referred to the total volume of timber, tending to the branch. The search for a variant of the track of a timber logging road close to the optimal for one of the criteria for the removal of the concentrated volume of timber is carried out in several stages. First, the optimal route variant is inscribed, inscribed in the grid of squares of the digital terrain model (the route passes along the sides and diagonals of squares). Then the found variant is smoothed with broken lines located in its vicinity. For each of the smoothed variants of the route, fourteen important technical and economic indicators are automatically calculated, allowing to make an informed decision when choosing the final version of the route of the future road. The accuracy of the construction of the digital relief model on a topographic map using the developed technique was estimated from the reference longitudinal profiles taken manually from the map in contours and built automatically using a digital terrain model. The results of the comparative analysis testify to the quite satisfactory accuracy of the developed method of manual digitization of maps. With the help of the same reference longitudinal profiles, it is possible to control the correctness of the results of digitization. To do this, it is sufficient to draw several rectilinear segments intersecting the simulated section in different directions and compare their longitudinal profiles constructed on the map with automatically calculated.

Middle of the road: enhanced habitat for salamanders on unused logging roads

Context Amphibians are particularly susceptible to the effects of habitat loss and fragmentation. The construction and use of roads is among the most common sources of habitat fragmentation and can lead to serious population declines. Unused resource access roads, such as those formerly used for logging, can still negatively impact salamanders and reduce habitat quality through edge effects. Unfortunately, habitat rehabilitation and enhancement is rarely attempted on unused forest roads. Aims Our aim was to elaborate on a previous study that tested several types of woody debris to mitigate the negative impacts of forest roads by creating a novel habitat on an unused forest road in Algonquin Provincial Park. Here we focus solely on the use of large, squared timbers and their use by salamanders. Methods We tested the application of coarse woody debris (CWD) to the surface of an unused forest road. CWD were sampled for salamanders seven times during the 2011 field season. Local climatic variables were tested against salamander captures, and CWD size preferences and patterns of salamander aggregation under CWD were assessed. Key results We observed five salamander species and 415 individuals under timbers in the 2011 field season. Larger timbers (>1m3) were preferred by all species observed and a significant proportion of animals were found in groups of two or more under larger timbers. High ambient temperature and low relative humidity negatively affected the number and species composition observed under timbers, suggesting that the efficiency of CWD as a survey method and enhanced habitat is season dependent. Implications Large timbers placed on unused forest roads may provide suitable refuges for migrating or dispersing forest salamanders while they attempt to cross the road. The tendency of salamanders to aggregate under CWD allows individual red efts to reduce water loss; however, red-backed salamanders are territorial and may drive off conspecifics. The use of large CWD may be an effective and low-cost method to rehabilitate unused forest roads and can be used to promote habitat connectivity for salamanders in targeted habitats, such as near wetlands, or for other species of concern.

The impact of logging roads on dung beetle assemblages in a tropical rainforest reserve

The demand for timber products is facilitating the degradation and opening up of large areas of intact habitats rich in biodiversity. Logging creates an extensive network of access roads within the forest, yet these are commonly ignored or excluded when assessing impacts of logging on forest biodiversity. Here we determine the impact of these roads on the overall condition of selectively logged forests in Borneo, Southeast Asia. Focusing on dung beetles along >40km logging roads we determine: (i) the magnitude and extent of edge effects alongside logging roads; (ii) whether vegetation characteristics can explain patterns in dung beetle communities, and; (iii) how the inclusion of road edge forest impacts dung beetle assemblages within the overall logged landscape. We found that while vegetation structure was significantly affected up to 34m from the road edge, impacts on dung beetle communities penetrated much further and were discernible up to 170m into the forest interior. We found larger species and particularly tunnelling species responded more than other functional groups which were also influenced by micro-habitat variation. We provide important new insights into the long-term ecological impacts of tropical logging. We also support calls for improved logging road design both during and after timber extraction to conserve more effectively biodiversity in production forests, for instance, by considering the minimum volume of timber, per unit length of logging road needed to justify road construction. In particular, we suggest that governments and certification bodies need to highlight more clearly the biodiversity and environmental impacts of logging roads.

Vegetation assessment of native tree species in Broussonetia papyrifera‐dominated degraded forest landscape in southern Ghana

AbstractQuestionDoes the invasive tree species Broussonetia papyrifera facilitate the natural regeneration of native tree species in a degraded tropical forest landscape?LocationAfram Headwaters Forest Reserve, southern Ghana.MethodsWe established sampling areas and assessed seedlings and saplings <5 cm DBH in nine habitats. The habitats were logging road, skid trail, large canopy gaps dominated by B. papyrifera, large canopy gaps dominated by invasive Chromolaena odorata, Nauclea diderrichii plantation, Mansonia altissima plantation, Terminalia ivorensis plantation, abandoned farmland and unlogged forest.ResultsWe found that the abundance of pioneers declined with increasing abundance of B. papyrifera. This trend was more pronounced in the farmland and in the N. diderrichii plantation. By contrast, increased abundance of B. papyrifera did not lead to a decrease in the abundance of the shade‐tolerant species. B. papyrifera seedlings and saplings were absent in the forest understorey. We also found a lower abundance and richness of some vulnerable tree species and valuable timber species in the N. diderrichii plantation and in gaps dominated by B. papyrifera. However, we recorded both shade‐tolerant and shade‐intolerant species in the gaps dominated by B. papyrifera.ConclusionsWe found both shade‐tolerant and shade‐intolerant species in the B. papyrifera‐dominated gaps. This can provide a basis for future studies to explore the potential of such tree species in restoration programmes targeted at B. papyrifera‐invaded sites. Our results also suggest that the integrity of the undisturbed forest patches in the landscape must be protected to help prevent B. papyrifera from spreading further. We suggest further studies should be conducted at replicated sites with a similar habitat that represent varying levels of invasion by B. papyrifera to draw conclusions regarding the species’ potential to facilitate regeneration of native tree species.

How persistent are the impacts of logging roads on Central African forest vegetation?

Summary Logging roads can trigger tropical forest degradation by reducing the integrity of the ecosystem and providing access for encroachment. Therefore, road management is crucial in reconciling selective logging and biodiversity conservation. Most logging roads are abandoned after timber harvesting; however, little is known about their long‐term impacts on forest vegetation and accessibility, especially in Central Africa. In 11 logging concessions in the Congo Basin, we field‐sampled a chronosequence of roads that, judging from satellite images, had been abandoned between 1985 and 2015. We assessed recovery of timber resources, tree diversity and above‐ground biomass in three zones: the road track, the road edge (where forest had been cleared during road construction) and the adjacent logged forest. The density of commercial timber species <15 cm d.b.h. was almost three times higher in the road track (321 individuals ha−1) and edge (267) than in the logged adjacent forest (97). Over time, tree species diversity converged to a comparable level between roads and adjacent forests, along with an increase in canopy closure. The average width of forest clearing for road construction was 20 m, covering a total 0·76% of the forest area inside concessions. After 15 years following abandonment, road tracks had recovered 24 Mg ha−1 of above‐ground woody biomass, which was 6% of that in the adjacent forest, while road edges had accumulated 167 Mg ha−1 (42%). Ten years after abandonment, roads were no longer penetrable by poachers on motorcycles. An exotic herb species was fully replaced by dominant Marantaceae that have even higher abundance in the adjacent forest. Synthesis and applications. Our evidence of vegetation recovery suggests that logging roads are mostly transient elements in the forest landscapes. However, given the slow recovery of biomass on abandoned road tracks, we advocate both reducing the width of forest clearing for road construction and reopening old logging roads for future harvests, rather than building new roads in intact forests. Road edges seem suitable for post‐logging silviculture which needs to be assisted by removing dominant herbs during the early years after abandonment while the road track is still accessible.

Effects of logging activities on selected soil physical and hydraulic properties for a claypan landscape

Previous studies have shown that once compacted, forest soils often recover slowly over many decades to pre-disturbed levels for soil properties such as bulk density or penetrometer resistance. This study was conducted to evaluate the effects of selected harvesting techniques on soil physical and hydraulic properties. The effects of logging roads, log landing areas, and logged areas on soil properties of water retention, saturated hydraulic conductivity (KSat), pore-size distributions, and bulk density were investigated on harvested sites within the Mark Twain National Forest in Callaway County, Missouri, USA on claypan landscape with a moderately well-drained Keswick soil (fine, smectitic, mesic Aquertic Chromic Hapludalfs). Soil cores (7.6cm by 7.6cm) were removed in four 10-cm depth increments. Bulk density was significantly greater (P<0.01), and KSat was significantly lower (P<0.01) under the logging road and log landing areas as compared to the logged area treatment. No statistical differences in bulk density and KSat values occurred among treatments at the deepest sampling depth (30 to 40cm). For the 0 and −0.4kPa soil water pressures, water retention was 14% greater and 9% greater for the logged areas versus the logging road and log landing areas averaged across all soil depths, respectively. For the macropores (>1000μm diameter) and coarse mesopores (60 to 1000μm diameter) combined, values were 131% greater for the logged area compared to logging road and log landing areas within the 0 to 10cm depth. From this study, the methods used in the logged area appear to have caused small changes to soil physical and hydraulic properties; however, significant changes to these properties occurred for logging road and the log landing areas.

Sparing forests in Central Africa: re‐use old logging roads to avoid creating new ones

Sparing forests in Central Africa: re‐use old logging roads to avoid creating new ones

Productivities of a wheel mounted harvester and forwarder system introduced from Europe on a logging road(&lt;SPECIAL ISSUE&gt;Forest operations with forest road networks)

Productivities of a wheel mounted harvester and forwarder system introduced from Europe on a logging road(&lt;SPECIAL ISSUE&gt;Forest operations with forest road networks)

К вопросу влияния расстояния видимости на различные режимы движения лесовозных автопоездов

К вопросу влияния расстояния видимости на различные режимы движения лесовозных автопоездов

К вопросу определения режима движения и эксплуатационных характеристик лесовозных автопоездов

К вопросу определения режима движения и эксплуатационных характеристик лесовозных автопоездов

Blakiston’s Fish-owl Bubo blakistoni and logging: Applying resource selection information to endangered species conservation in Russia

SummaryBlakiston's Fish-owl Bubo blakistoni is classified as ‘Endangered’ by IUCN; this species is associated with riparian old-growth forests in north-east Asia, a landscape threatened by a variety of impacts (e.g. logging, agricultural development, human settlement). We examined a 20,213 km2 study area in Primorye, Russia, and assessed the ability of the protected area network to conserve Blakiston's Fish-owls by analysing resource selection of radio-marked individuals. Based on resource selection functions, we predicted that 60–65 Blakiston's fish-owl home ranges could occur within the study area. We found that the protected area network within our study area contained only 19% of optimal Blakiston's fish-owl habitat and contained only eight potential home ranges (five of these within a single protected area—Sikhote-Alin Biosphere Reserve). We also found that 43% of optimal Blakiston's Fish-owl habitat was within current logging leases; lands capable of supporting habitat equivalent to 24 home ranges. The remaining optimal habitat (38%) was on federal land and potentially contained 28–33 Blakiston's Fish-owl home ranges. The current protected area network, by itself, is not sufficient to conserve the species because relatively few home ranges are actually protected. Therefore, outside of protected areas, we recommend protecting specific locations within potential home ranges that likely contain suitable nest and foraging sites, maintaining integrity of riparian areas, modifying road construction methods, and closing old and unused logging roads to reduce anthropogenic disturbance to the owls and the landscape.

High prevalence of cannabis use among Aka foragers of the Congo Basin and its possible relationship to helminthiasis.

Little is known about cannabis use in hunter-gatherers. Therefore, we investigated cannabis use in the Aka, a population of foragers of the Congo Basin. Because cannabis contains anthelminthic compounds, and the Aka have a high prevalence of helminthiasis, we also tested the hypothesis that cannabis use might be an unconscious form of self-medication against helminths. We collected self- and peer-reports of cannabis use from all adult Aka in the Lobaye district of the Central African Republic (n = 379). Because female cannabis use was low, we restricted sample collection to men. Using an immunoassay for Δ9-tetrahydrocannabinol-11-oic acid (THCA), a urinary biomarker of recent cannabis consumption, we validated cannabis use in men currently residing in camps near a logging road (n = 62). We also collected stool samples to assay worm burden. A longitudinal reinfection study was conducted among a subsample of the male participants (n = 23) who had been treated with a commercial anthelmintic 1 year ago. The prevalence of self- and peer-reported cannabis use was 70.9% among men and 6.1% among women, for a total prevalence of 38.6%. Using a 50 ng/ml threshold for THCA, 67.7% of men used cannabis. Cannabis users were significantly younger and had less material wealth than the non-cannabis users. There were significant negative associations between THCA levels and worm burden, and reinfection with helminths 1 year after treatment with a commercial anthelmintic. The prevalence of cannabis use among adult Aka men was high when compared to most global populations. THCA levels were negatively correlated with parasite infection and reinfection, supporting the self-medication hypothesis.

Legacy of logging roads in the Congo Basin: How persistent are the scars in forest cover?

Logging roads in the Congo Basin are often associated with forest degradation through fragmentation and access for other land uses. However, in concessions managed for timber production, secondary roads are usually closed after exploitation and are expected to disappear subsequently. Little is known about the effectiveness of this prescription and the factors affecting vegetation recovery rate on abandoned logging roads. In a novel approach we assessed logging roads as temporary elements in the forest landscape that vary in persistence depending on environmental conditions. We analyzed road persistence during the period 1986–2013 in adjacent parts of Cameroon, Central African Republic and Republic of Congo. Three successive phases of road recovery were identified on LANDSAT images: open roads with bare soil, roads in the process of revegetation after abandonment and disappeared roads no longer distinguishable from the surrounding forest. Field based inventories confirmed significant differences between all three categories in density and richness of woody species and cover of dominant herbs. We used dead‐end road segments, built for timber exploitation, as sampling units. Only 6% of them were identified as being re‐opened. Survival analyses showed median persistence of four years for open roads before changing to the revegetating state and 20 years for revegetating roads before disappearance. Persistence of revegetating roads was 25% longer on geologically poor substrates which might result from slower forest recovery in areas with lower levels of soil nutrient content. We highlight the contrast amongst forests growing on different types of substrate in their potential for ecosystem recovery over time after roads have been abandoned. Forest management plans need to take these constraints into account. Logging activities should be concentrated on the existing road network and sites of low soil resource levels should be spared from business‐as‐usual exploitation.