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1.
Hikaru Kitahara Yoichi Okura Toshiaki Sammori Akiko Kawanami 《Journal of Forest Research》2000,5(4):231-236
Universal Soil Loss Equation (USLE), originally developed by the USDA for agricultural lands and then used throughout the
world, was applied in mountainous forest terrain in Japan. The slope length and steepness factors were extended for long slope
lengths and steep slopes by recalculating the data from available literature in Japan and by using data from supplementary
erosion experiments. As such, we conclude that the USLE can be used successfully to estimate surface erosion on long, steep
mountainous forest slopes. The cover and management factors of many kinds of natural and artificial forest stands, cutting
types, and disturbance regimes were calculated from the literature. The support practice factors of many types of soil and
water conservation practices were also calculated from published information. Based on these results, we showed that the USLE
can be applied to estimations of soil erosion from wide areas including many kinds of agricultural and forest lands.
This study was funded by the Agricultural, Forestry, and Fishery Technology Council Office for comprehensive studies on agriculture,
forestry, and fisheries and the agricultural, forestry, and fishery trading, resources, and environments. 相似文献
2.
Moso bamboo (Phyllostachys pubescens) is cultivated for edible bamboo shoot production in Japan. Yamagata Prefecture is located in a heavy-snowfall region at the northern limit of the cultivated area. However, snow damage to bamboo culms occurs every year and decreases bamboo shoot production. “Uradome” is a treatment that involves cutting off the upper portion of the new culms when the bamboo shoot is almost fully grown. We studied the effect of “Uradome” implementation on incidence of snow damage to bamboo culms. In addition, we investigated terrain characteristics of bamboo forest at sites where snow damage occurred. As a result, the higher the degree of “Uradome” was, the lower the damage rate was. Furthermore, the results revealed that implementation of “Uradome” prevents snow damage to culms. It is considered that snow damage may be prevented by rendering the culm shape straight as a result of “Uradome”. The results also indicated that snow damage is more likely to occur on steep slopes. Factors that influence the incidence and severity of snow damage are considered to differ between Japan and other countries. Therefore, it is desirable to adopt preventative measures against snow damage, such as the “Uradome” method, irrespective of the local climate and terrain. 相似文献
3.
Davide Viglietti Margherita Maggioni Enrico Bruno Ermanno Zanini Michele Freppaz 《林业研究》2013,24(4):633-642
The presence of a thick snowpack could interfere with forest stability, especially on steep slopes with potential damages for young and old stands. The study of snow gliding in forests is rather comple... 相似文献
4.
Berdimohammad Agherkakli Seyed Hamidreza Sadeghi Eric Zenner 《Scandinavian Journal of Forest Research》2014,29(5):499-505
Reinforcement of skid trails with slash has been shown to reduce soil disturbances, but there have not been any studies documenting the mitigating effects following traffic of harvest equipment traffic on steep mountainous skid trails. The objective of this study was to quantify potentially mitigating effects of slash cover on soil compaction and rutting on skid trails in mountainous hardwood forests. The effects of the placement of no slash (bare soil), light density slash (7.5 kg m?2) and heavy density slash (17.5 kg m?2) in a skid trail following one, five, and nine machine passes on both gentle slopes <20% and steep slopes >20% in a downhill skidding operation by a steel-tracked skidder were studied. Bulk density and rut depth increased following harvest equipment traffic on both slope gradients. Compared to bare soils, soil bulk density was not significantly reduced by light slash density; however, soil bulk density was significantly reduced by heavy slash up to five machine passes on steep slopes. Light and heavy slash significantly reduced rut depth in both slope classes. The study revealed a high protective role of slash, particularly on steep skid trails. However, benefits of slash to mitigate soil compaction were limited to five passes, after which the slash deteriorated and only provided benefits against rutting. 相似文献
5.
《Journal of Sustainable Forestry》2013,32(3-4):237-250
Abstract Processes and mechanisms of large-gap creation in an old-growth beech forest on Mt. Garyu in southwestern Japan by Typhoon 9119 are discussed. In the large gap of 4,100 m2, damaged trees were mostly Fagus crenataand the main cause of gap creation was uprooting of tall, large diameter, canopy trees. Also in the other parts of the beech forest, the main cause of gap creation was uprooting of canopy trees. The large gap was created by the sequential and domino-like fall of multiple canopy trees blown down by windstorms that followed the passage of the typhoon itself. In the large gap, it is possible that the windstorm which attacked and moved over the slope was strengthened by topography. In addition, the risk of gap enlargement will increase on steep slopes more than on gentle slopes when the up-slope is on the leeward of the wind. The large-scale disturbance caused by Typhoon 9119 as a catastrophic windstorm may influence the pattern and process in forest regeneration. 相似文献
6.
7.
We evaluated the protective effects of floor cover against soil erosion in three types of forest located on steep slopes
under a humid climate: 22- and 34-year-old Chamaecyparis obtusa (hinoki), 34-year-old Cryptomeria japonica (sugi), and 62-year-old Pinus densiflora (red pine) stands. We measured sediment transport rates (sediment mass passing through one meter of contour width per millimeter
of rainfall), using sediment traps, before and after removing floor cover. Raindrop splash erosion was dominant in the experimental
stands. Floor cover percentage (FCP) during the preremoval stage varied from 50% to 100% among the four stands, and sediment
transport rates ranged from 0.0079 to 1.7 g m−1 mm−1. The rates increased to 1.5–5.6 g m−1 mm−1 immediately after removing floor cover, and remained high throughout the experiment. The presence of physical cover near
the ground has a crucial effect on sediment transport on forested slopes. The protective effect ratio (the ratio of the sediment
transport rate in a control plot to that in the removal plot) in a young hinoki stand, in which the FCP decreased markedly,
was 0.3 at most, which is close to the rate for bare ground. The protective effect ratio in the red pine stand was ≤0.003.
We concluded that the protective effect of floor cover in undisturbed forests in Japan differs by over two orders of magnitude,
based on comparisons with previous studies.
Received: March 11, 2002 / Accepted: August 16, 2002
Present address: Department of Forest Site Environment, Forestry and Forest Products Research Institute, Ibaraki 305-8687 Japan Tel. +81-298-73-3211;
Fax +81-298-74-3720 e-mail: miura@affrc.go.jp
Present address: Department of Forest Site Environment, Forestry and Forest Products Research Institute, Ibaraki 305-8687 Japan Tel. +81-298-73-3211;
Fax +81-298-74-3720 e-mail: miura@affrc.go.jp
Acknowledgments This study was supported by the Research Council of the Ministry of Agriculture, Forestry, and Fisheries, of Japan. We thank
H. Ujihara, S. Ujihara, and M. Ogasawara in Otoyo, Kochi, who provided the experimental stands used in this study. We also
thank K. Hirai, S. Kuramoto, E. Kodani, and the rest of the staff at the Shikoku Research Center, Forestry and Forest Products
Research Institute, for their help in conducting the experiments.
Correspondence to:S. Miura 相似文献
8.
日本的山地治理与开发扬立文（中国林科院林业所，北京１０００９１）编者按：林业部于今年初推出的“山区林业技术开发计划”，即“富山计划”，已在各地全面启动。这项计划是林业部根据我国山区的实际情况制定的，是一项旨在充分发挥科学技术的先导作用，以山区资源为基... 相似文献
9.
The protection of people, buildings and infrastructure against natural hazards is one of the key functions of mountain forests. Since the protective function strongly depends on small-scale local conditions such as terrain and stand characteristics, spatially explicit evaluation methods are necessary to provide information required for an effective and cost-efficient forest management. Risk analyses are recognized as the best method for estimating the danger from various natural hazards. Currently, however, risk-based strategies are rarely addressed in the management of protection forest. We present and discuss a risk-based approach to evaluate the protective effect of mountain forests in a spatially explicit manner to demonstrate the advantages of future risk-based protection forest management. We illustrate the approach by performing a GIS-based risk analysis in the case study area ‘Bannwald of Andermatt’ (Switzerland) for a 300-year snow avalanche event. Classifying forest structures based on aerial photographs allowed developing different forest cover scenarios and modeling potential avalanche release areas within the forest. Potential avalanche release areas above the forest and the avalanche run-out distances under five different scenarios of forest cover were calculated by using a two-dimensional avalanche simulation model. We calculated the annual collective risk for each scenario and compared the change in risk to reveal the spatial distribution of the protective effect of the forest. Resulting risks differed strongly between forest cover change scenarios. An enlargement of an existing wind-disturbed area within lower parts of the slope resulted only in a slight increase of risk. In contrast, the effect of an unforested area in the upper parts of the observed forest more than doubled the risk. These results show how a risk-based approach can help to quantify and illustrate the impact of differences in forest cover on the protective effect of mountain forests. It is a promising approach to determine the economic value of protection forests and thus provide quantitative and qualitative information for cost-efficient forest maintenance planning. With regard to the achievements of research to date, the presented approach may serve as a valuable method to support decision-making in a future protection forest management. 相似文献
10.
On the basis of 268 direct sika deer observations and 212 ratio locations of three individuals, the influence of snow on deer
distribution was studied. During the period of snow absence or its shallow cover, the deer did not show any preferences towards
slope aspect. However, when the snow coverage became deeper, the deer used westerly exposures (having shallower snow cover)
more intensively. Later on, when the snow started to melt on the easterly slope aspects deer mostly used those exposures due
to relatively abundant food resources. 相似文献
11.
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Bird species diversity and bird species richness were surveyed in a natural mixed forest (mature forest) and in a coniferous
plantation (30–40 years old) monthly from 1990 to 1994. These forests were 20 km apart and had similar weather conditions
and soil types. There were larch and cedar plantations, and hardwoods along streams in the coniferous plantation. In the natural
mixed forest, 55 bird species were found, whereas 40 species were recorded in the coniferous plantation. The species diversity
of bird communities was significantly higher in the natural mixed forest than in the coniferous plantation mixed with hardwood
trees. This result indicates that the coniferous plantation mixed with hardwood trees, presumed to be a more simplified environment,
is likely to be less inhabitable for many bird species than the natural mixed forest, suggesting a relationship between the
diversity of the forest environment and the diversity of the bird community. A higher number of bird species was recorded
in the small coniferous forest mixed with hardwood trees compared with those in the coniferous plantation. The mixing of broad-leaved
trees in a coniferous plantation was suggested to be effective in increasing number of bird species. These tendencies were
recorded all through the year during our study. In snow-covering periods, both the diversity and the bird species richness
fell in all study sites every year. Snow cover would have greater effect on bird species diversity in the coniferous plantation
than in other forest types probably due to diet shortages caused by the snow cover over the forest floor. 相似文献
14.
15.
《Southern Forests》2013,75(3-4):123-129
Mulanje Mountain is one of the examples of tropical montane landscapes with plant populations varying in size from small fragments of less than 1 ha to riverine strips and stands of more than 100 ha. Seed availability is a potential limiting factor in vegetation recovery in such landscapes. Field observation on seed rain and seed limitation was conducted in 2008 and 2009 in three sizes of forest fragments at three sites on the mountain to investigate: (1) whether size of Widdringtonia whytei forest patches influences seed-rain density; (2) whether W. whytei seed rain occurs in a specific season; and (3) if seed limitation differs from within forest patches to the adjacent non-forest patch habitats. The results showed that there was a distinct difference in seed-rain density among fragments where large fragments (>20 trees) collected higher seed-rain density (10.4 ± 0.9 seeds m?2 y?1) than small fragments (1.1 ± 0.4 seeds m?2 y?1). The seed-rain density differed significantly between 2008 (2.1 ± 0.6 seeds m?2 y?1)and 2009 (6.1 ± 1.1 seeds m?2 y?1). Seed rain was recorded every month of the year but the densities were not significantly different among months. Seed-rain density was highest inside the forest fragments (12.04 ± 2.3 seeds m?2 y?1) and decreased drastically and very significantly at the edges (1.0 ± 0.8 seed m?2 y?1) and outside the forest fragments (0.11 ±0.1 seed m?2 y?1). Seed limitation was strong (0.98) on all sites; 0.95 in large fragments and 0.99 in medium and small fragments, respectively. Therefore, it can be concluded from this study that the presence and retention of more seed trees ensures the continued availability of W. whytei seed on the forest floor within the context of limited seed dispersal. 相似文献
16.
Yagil Osem Ela Zangy Eitan Bney-Moshe Yosi Moshe Naftali Karni Yehuda Nisan 《Forest Ecology and Management》2009
The aim was to study the potential for using natural regeneration as a basis for transformation of simply structured conifer plantations into mixed Mediterranean forests. We studied the variation along a rainfall gradient, in the natural regeneration of tree species in the understory of planted 40- to 50-year-old Aleppo pine (Pinus halepensis) forests. The study was conducted within the Mediterranean zone of Israel, which extends from the semiarid northern Negev desert (rainfall ca. 300 mm yr−1) in the south to the humid Upper Galilee in the north (ca 900 mm yr−1). Cover and height, density, and species composition of regenerating trees were measured on south- and north-facing slopes in forest sites of comparable silvicultural history (site preparation methodology, planting density and thinning regime) distributed along the rainfall gradient. Altogether, 12 species of regenerating native broadleaved trees were found in the understory of the various forest sites. Surface cover, density and species richness increased linearly along the entire rainfall gradient, on both north- and south-facing slopes, ranging from zero in the driest forest sites up to 85% cover, 7980 trees ha−1 and 4.5 species per 200 m2, respectively, in the most humid ones. Species composition of regenerating trees was also related to rainfall amount, through changes in the relative importance of species along the rainfall gradient. The effect of topographic aspect on tree regeneration was inconsistent, i.e., the interaction Rainfall × Aspect was significant. Nevertheless, the general trend showed better regeneration on north-facing slopes. Most of the regenerating trees in the understory were small, i.e., less than 100 cm in height, with no clear effect of rainfall amount and topographic aspect on the relative abundance of height classes. Regeneration by Aleppo pine was highly variable among and within the different forest sites and ranged from 0 to 1565 trees ha−1, with no clear relationships with rainfall amount and topographic aspect. In light of our results we propose that the future structure of forests should vary with respect to annual rainfall amount within possible silvicultural scenarios. 相似文献
17.
Leaf-fall phenology was studied in a cool–temperate deciduous broad-leaved forest in central Japan in relation to the topographic environmental gradients that occur along a short mountain slope. Leaf-fall phenology was described quantitatively using data from leaf litter collected along the slope. In autumn, leaf fall at the study site tended to occur slightly earlier on the upper slope than on the lower slope. This pattern was found at both the stand and the species levels. Our results suggest that leaf-fall phenology may be affected by difference in microclimatic conditions, because environmental conditions are thought to be more severe on the upper slope than on the lower slope. The less intensive methods used in this study, the litter trap method, and Dixon’s model succeeded in quantifying the phenological patterns of leaf fall within stands and within species along the short mountain slope. 相似文献
18.
Transport rates of surface materials on steep forested slopes induced by raindrop splash erosion 总被引：1，自引：0，他引：1
We used small (25 cm) sediment traps to evaluate the properties of surface material transport on steep slopes under humid
temperate conditions in the Shikoku district of Japan. We sampled ten stands ofChamaecyparis obtusa (hinoki),Cryptomeria japonica (sugi),Pinus densiflora (red pine), and deciduous hardwood forest. Transport rates were estimated by dividing the amount of mass transported by the
mass of rainfall during a given period. These rates varied widely among the ten stands: 0.0065–0.31 g m−1 mm−1 (a difference of two orders of magnitude) for fine earth, 0.00017–0.97 (four orders) for gravel, and 0.020–0.24 (one order)
for litter. The transport rates in young hinoki stands with a low floor cover percentage (FCP) showed no seasonal changes.
The transport rates changed by one or two orders of magnitude in hardwood forests with clear seasonal changes in FCP, as well
as in juvenile and middle-aged hinoki and sugi stands, where understory floor cover increased and decreased seasonally. Rainfall
intensity, however, showed no positive effects on transport rates, even in stands that had changing transport rates. The rates
were mostly determined by forest type. We demonstrate that transport rate is an inherent property of a forest that reflects
floor cover conditions and indicates the potential of surface material transport.
This study was supported by the Research Council in the Ministry of Agricuture, Forestry and Fisheries, Japan. 相似文献
19.
Large forest fires have recently increased in frequency and severity in many ecosystems. Due to the heterogeneity in fuels, weather and topography, these large fires tend to form unburned islands of vegetation. This study focuses on a large forest fire that occurred in north-eastern Spain in 1998, which left large areas of unburned vegetation within its perimeter. Based on a satellite post-fire severity map we searched for the relative influence of biotic and abiotic factors leading to unburned island formation. We divided the area of the fire into individual units we called “slopes” which were meant to separate the differential microclimatic effects of contrasted aspects. The number of unburned islands and their areas were related to 12 variables that influence their formation (i.e. land cover composition, aspect, steepness, forest structure, two landscape indices and weather variables). We hypothesized that unburned vegetation islands would concentrate on northern aspects, in less flammable forests (i.e. broadleaf species) and higher fragmentation to interrupt the advance of fire. While north and western aspects did have a higher presence of unburned vegetation islands, our study suggests greater presence of islands in slopes that are larger (i.e. more continuous areas with relatively homogeneous aspect), with greater proportions of forest cover, with higher wood volumes and with lower proportions of broadleaf species. Climate also played a role, with relative humidity and wind speed positively and negatively correlated to island formation, respectively. Unburned vegetation was more frequent on slopes with lower diversity of land covers and higher dominance of one land cover in the slope. Since slopes with only one land cover (i.e. forests) had more islands than slopes with multiple cover types, we infer that under severe meteorological conditions, fragmented forests can be more affected by wind and by water stress, thus burning more readily than forests that are protected from this edge phenomenon. These results would reinforce forest management strategies that avoid linear features (fire-lines and fire-breaks), to enhance fuel treatments that focus on areas and minimize fragmentation. 相似文献
20.
植物作为预防水土流失的首要手段，在园林边坡的应用中发挥着重要作用。对白云山风景区的33个园林边坡的地被植物进行调查评价，运用层次分析法，构建以生态性、适应性及观赏价值3个准则层及10个指标因子的评价模型，对边坡地被植物进行筛选评价。结果表明，应用频率较高的18种边坡地被植物可分为3个等级，其中Ⅰ级有3种，Ⅱ级有11种，Ⅲ级有4种，鹅掌藤Heptapleurum arboricola、红花檵木Loropetalum chinense var. rubrum、假连翘Duranta erecta等是边坡植物材料的优良选择。最后提出优先考虑植物的护坡能力，提高乡土植物比例，丰富植物层次等坡地植物配置建议 相似文献