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1.
We evaluated the survival and growth of Abies homolepis and Picea jezoensis var. hondoensis seedlings on Mt. Ohdaigahara, where the population of sika deer (Cervus nippon) is high and an experimental fence has been in place for 13 years. No significant differences were detected in the survival
of small seedlings between fenced and unfenced plots. The growth of A. homolepis was significantly higher in the fenced plot, but growth of P. jezoensis var. hondoensis did not show significant differences between fenced and unfenced plots. Seedlings of height ≤5 cm in the forest floor vegetation
of the unfenced plot were probably too small for deer to find and browse, so they survived. 相似文献
2.
Regeneration of beech (Fagus crenata) forests depends on the formation of canopy gaps. However, in Japan Sea-type beech forests, a dwarf bamboo (Sasa kurilensis) conspicuously occupies sunny gaps. Therefore,F. crenata seedlings must escape the severe interference ofS. kurilensis in the gaps and persist beneath a closed canopy of the beech forest. We hypothesized that the growth ofF. crenata seedlings in the understory would be favored by their being more plastic thanS. kurilensis in photosynthetic and morphological traits, which would support the matter production ofF. crenata seedlings in a wide range of light availabilities. To examine this hypothesis, the photosynthetic-light response of individual
leaves and the biomass allocation in aboveground parts (i.e., the culm/foliage ratio) were surveyed at sites with contrasting light availabilities in a Japan Sea-type beech forest in
central Japan. InF. crenata, photosynthetic light utilization efficiency at relatively low light was greater, and the dark respiration rate was smaller
in the leaves of seedlings (10 cm in height) beneath the closed canopy than in the leaves of saplings at the sunny forest
edge. The culm/foliage (C/F) ratio of theF. crenata seedlings at the shady site was small, suggesting effective matter-production beneath the beech canopy. On the other hand,S. kurilensis both in the gap and beneath the beech canopy showed low plasticity in photosynthesis and the culm/foliage ratio. Because
the shoot density ofS. kurilensis was smaller beneath the beech canopy than in the gap, the light availability at the bottom of theS. kurilensis layer was greater beneath the beech canopy. These results suggest that the photosynthetic productivity of theF. crenata seedlings would be enough for the seedlings to survive in the understory with a low density ofS. kurilensis shoots beneath the closed beech canopy. 相似文献
3.
Hiromi Mizunaga Shizuo Sako Yuri Nakao Yoshitaka Shimono 《Journal of Forest Research》2005,10(6):481-486
The refugee population of Fagus crenata in the Takakuma Mountains, Kyushu, Japan, represents the southern limit of this species' distribution area. Because this
population is the most exposed to the global warming effect, records of this population are likely to provide useful information
on the response of this species to global warming. The aim of this study was to record the present status of this valuable
population, enabling judgment of its sustainability. The density of successive F. crenata trees and saplings was low regardless of the coverage of dwarf bamboo. Moreover, the proportion of empty nuts observed was
considerably high, suggesting to be the likely major factor limiting recruitment of saplings or successors in this population.
Radial growth of F. crenata was shown to have been decreasing for the past 50 years, and there was a significantly negative correlation with the warmth
index. The decreasing growth rate and poor regenerative ability caused by the high proportion of empty nuts suggest the possibility
that this population will degrade further in the future, possibly being replaced by shrubs and small tree species. 相似文献
4.
Ikue Murata Sigefumi Saruki Katsuyoshi Kubota Sachiko Inoue Naoaki Tashiro Tsutomu Enoki Yasuhiro Utsumi Susumu Inoue 《Journal of Forest Research》2009,14(5):296-301
Effects of sika deer (Cervus nippon) and dwarf bamboo (“sasa;” Sasamorpha borealis) on seedling emergence and survival were investigated in cool-temperate mixed forests in the Kyushu mountain range, Japan.
We compared the effects of sika deer between two sites with different sika deer densities. One site (no-sasa forest) has sparse
cover of S. borealis and a high density of sika deer, and the other site (sasa forest) has dense cover of S. borealis with a low density of sika deer. In the no-sasa forest, more seedlings emerged and the survival rate of the seedlings was
higher compared with the sasa forest. Compared with the sasa forest, the canopy in the no-sasa forest was more open, the organic
layer was shallower and drier, the mean daily soil temperature was higher, and soil temperature fluctuated more widely. Those
environmental parameters did not differ between unfenced and fenced plots. The comparison between the sasa and no-sasa forests
suggested that removal of S. borealis by sika deer had an indirect positive effect on seedling emergence and survival. However, the fenced-plot experiments indicated
that sika deer inhibited seedling emergence and survival. These contradictory conclusions could result from the much larger
negative effects of S. borealis on seedling emergence and survival compared with the effects of sika deer browsing. 相似文献
5.
We evaluated the effect of bark stripping by sika deer (Cervus nippon), and subsequent wood decay, on tree fall in a coniferous forest on Mt Ohdaigahara in central Japan from July to September
2006. This valuable primeval coniferous forest is declining because of bark stripping. Broken trunks of Abies homolepis and Picea jezoensis var. hondoensis had more serious decay and larger bark-stripping wounds on the trunk than standing trees, suggesting that bark stripping
causes trunk decay and results in broken trunks and uprooting by typhoons. 相似文献
6.
Browsing by sika deer (Cervus nippon) has significant negative effects on regeneration in many forests in Japan; however, the effects of browsing on regeneration
processes have not been determined quantitatively. Our study was conducted in Abies sachalinensis plantations in seven tracts with differences in deer abundance on Hokkaido, northern Japan, to identify indicators for the
effects of deer on the regeneration of broad-leaf species from observing seedlings. Five 5 × 20-m plots were located within
each tract, and the densities of seedlings 30–200 cm tall and percentages of browsed seedlings were determined. We used sightings
per unit effort (SPUE) by hunters and spotlight survey counts (SLCs) as indices of deer abundance for each tract. Seedling
density was negatively correlated with deer abundance and coverage of dwarf bamboo, and basal areas of overstory trees also
affected number of seedlings. Percentage of browsed seedlings was positively correlated with deer abundance, and it was affected
by deer preferences among seedling species. However, the percentage of browsed seedlings was more clearly related to deer
abundance than seedling density. There were few seedlings of tree species ≥100 cm tall in tracts with the highest deer abundance.
Based on these results, deer abundances of SPUE >6 sightings per hunter-day or SLC >15 animals per 10 km are likely to prevent
regeneration of broad-leaf species. The percentage of browsed seedlings and density and browsing damage on tree seedlings
≥100 cm tall are useful indicators of the effects of deer. 相似文献
7.
Seedling ofWisteria floribunda, which belongs to the twiner type of climbing plants, were planted in nursery and the effect of support on the growth of
the seedlings was tested. The seedlings were grown with 240 cm-height and 120 cm-height supports (the culms of a dwarf bamboo),
and without support. Positive effect of the supports and its length were observed for stem length ofW. floribunda at the end of the growing season. The positive effect of support was also observed for total dry weight. Total dry weight
with 240 cm-height support reached more than the double of the seedlings without support. These effects of the support were
attributed to die-back behavior of the twining stem, which detached from the support or did not encounter the support. Diameter
of the stems without support showed a rapid decrease toward the stem tip, while that with support were relatively constant
when they were twining around the support. The existence of the support also affected the dry matter allocation in this species;
supported seedlings allocated larger proportion of biomass to current-year stems than unsupported seedlings, although the
allocation to the roots was smaller in the supported treatments. Support availability may be critical for the establishment
and further growth of the seedlings ofW. floribunda which regenerate at the forest edge and canopy gaps.
A part of this report was presented at the 107th Annual Meeting of the Japanese Forestry Society, at Tsukuba, April, 1996. 相似文献
8.
The indirect consequence of sika deer (Cervus nippon) grazing on the regeneration of Picea jezoensis var. hondoensis through its effect on the small rodent population was assessed by evaluating seed predation by mice inside and outside the
deer-proof fence on Mt Ohdaigahara, central Japan. Following construction of the deer-proof fence, Sasa nipponica, which covers the forest floor and is the main forage of deer, grew thicker inside the fence due to the absence of deer grazing
than outside of the fence. Higher numbers of two species of woodmice (Apodemus speciosus and A. argenteus) were found inside the fence, possibly because the thick S. nipponica growth provides better cover. Inside the fence, more seeds of P. jezoensis var. hondoensis were eaten by the mice than outside the fence. These results suggest that the mouse populations inside the fence increased
due to changes in S. nipponica cover, which subsequently increased seed predation by the mice, possibly preventing regeneration of P. jezoensis var. hondoensis. 相似文献
9.
Food habits of sika deer,Cervus nippon centralis temminck, in Mt. Ohdaigahara, central Japan, were investigated by the fecal analysis method from September, 1990, to June,
1991. The fecal analysis showed that the percentage ofSasa nipponica Makino et Shibata in the fecal composition was approximately 50% throughout the year, indicating that it was the main food
plant. Bark and twigs were also found in the feces in all seasons, suggesting that the deer ate bark throughout the year.
Even though the amount of the bark eaten per capita was small, the high density of deer may possibly cause serious bark damage.
Barking can be one of the main causes of the mortality ofPicea jezoensis Sieb. et Zucc. var.hondoensis (Mayr) Rehder andAbies homolepis Sieb. et Zucc. in Mt. Ohdaigahara.
A part of this study was presented at the 105th Annual Meeting of the Japanese Forestry Society (1994). 相似文献
10.
Hiromitsu Kisanuki Arisa Nakai Akiko Nadamoto Masako Wakino 《Journal of Forest Research》2009,14(6):342-348
We determined patterns of microsite suppression in dwarf bamboo Sasa nipponica when grazing deer were absent. This bamboo species is able to outcompete Hondo spruce (Picea jezoensis var. hondoensis) saplings under many environmental circumstances. We set up two 10 × 100 m plots inside a deer-proof fence within a subalpine
forest on Mt. Ohdaigahara, central Japan, and two similarly sized plots outside the fence. Within the plots, we surveyed microsites
where spruce saplings grew. We measured height and shoot elongation of all spruce saplings, and culm height and cover ratios
of dwarf bamboo growing around each spruce sapling. Spruce sapling density and average height were higher inside the deer-proof
fence than outside, as were bamboo height and cover. Thus, there was a negative effect of deer browsing on vegetation parameters
outside the fence and a suppression of the negative effect of bamboo on spruce sapling growth inside the fence. Spruce sapling
height was higher in tree-fall pits than in other microsites inside the fence, whereas both dwarf bamboo height and cover
were lower in pits and rocky sites than elsewhere. In soil and collar microsites, spruce sapling shoot growth was lower and
bamboo height and cover were higher than in pits and rocky sites. Inside the fence, dwarf bamboo cover was high, but pits
and rocks suppressed its growth, allowing spruce saplings to flourish. To restore heavily damaged spruce forests with advanced
saplings, it will be necessary to construct deer-proof fences and create and maintain microsites with pits and rocks. 相似文献
11.
Ophiostoma species were isolated from bark beetles and Abies mariesii, A. veitchii and A. homolepis attacked by the beetles in Nikko, Tochigi, central Honshu, Japan. One to two Ophiostoma species were frequently isolated from each species of bark beetle. Ophiostoma subalpinum was the most common associate of Cryphalus montanus. Ophiostoma sp. B as well as O. subalpinum was a common fungus associated with Polygraphus proximus. Ophiostoma europhioides was isolated from Dryocoetes hectographus and D. autographus as one of the common associates. Ophiostoma sp. J and Ophiostoma sp. S were frequently isolated from D. autographus and D. striatus, respectively. These fungi seem to have specific relationships with particular bark beetles. Ophiostoma sp. B, Ophiostoma sp. J and Ophiostoma sp. S have unique morphological characteristics and appear to be new species. Five trees of A. veitchii, approximately 43 years old, were inoculated with five Ophiostoma species to assess the relative virulence of the fungi. Ophiostoma subalpinum, Ophiostoma sp. B, and O. europhioides had relatively higher virulence than the other species studied. 相似文献
12.
[目的]研究缓释肥N/P养分配比及加载量对南方红豆杉、浙江楠和浙江樟苗木生长发育的影响,以科学指导大规格容器苗的高效培育。[方法]试验采用析因设计,研究N/P养分配比(1.75∶1、2.25∶1、2.75∶1和3.25∶1)及其加载量(1.5 kg·m~(-3)、2.5 kg·m~(-3)、3.5 kg·m~(-3)和4.5 kg·m~(-3))对3种珍贵树种2年生容器苗生长、株高生长节律、干物质积累及叶片SPAD值等影响。[结果]缓释肥N/P养分配比及加载量对3个树种容器苗生长及SPAD值影响不一。南方红豆杉、浙江楠和浙江樟干物质积累及根冠比在不同N/P养分配比间差异不大,浙江樟苗木生长受N/P养分配比影响较小,随着N/P养分配比增加,明显促进了浙江楠容器苗生长,却抑制了南方红豆杉的生长。缓释肥加载量对3个树种2年生容器苗生长和干物质积累的影响均达到极显著水平,随着缓释肥加载量增加可明显地促进3种树种株高、地径生长及干物质积累,增加了浙江楠地上干物质积累及南方红豆杉地下干物质积累,而对浙江樟根冠比影响未达统计学显著水平,但均显示加载量在3.5 kg·m~(-3)时达到最大值。N/P养分配比及与加载量的互作对3个树种苗木生长和干物质积累影响不明显,说明N/P养分配比对3个树种容器苗生长和质量的影响不因加载量的改变而变化或变化不大,反之亦然。随着缓释肥N/P养分配比的增加,可明显地延长南方红豆杉苗木株高的线性生长期,提高浙江楠株高的线性生长量,但对浙江樟株高的线性生长影响不明显。3种树种苗木叶片SPAD值差异很大,N/P养分配比及加载量并未改变3种树种叶片SPAD值动态变化规律,但随着N/P养分配比提高使南方红豆杉和浙江樟叶片SPAD值的起伏强度增大,3个树种SPAD值动态变化均随加载量增加而增大。[结论]南方红豆杉大规格容器苗培育较适宜的N/P养分配比为A1(1.75∶1)或A2(2.25∶1),而浙江楠和浙江樟为A3(2.75∶1),加载较高量的缓释肥F3(3.5 kg·m~(-3))可明显促进3种树种大规格容器苗的生长及SPAD值的提高,但加载量超过一定限度后,反而影响苗木的生长发育。 相似文献
13.
[目的]比较分析了不同海拔梯度高节竹笋外观品质、营养品质和食味品质的差异,为高节竹高品质竹笋培育提供参考。[方法]试验采集3个海拔梯度(110、370、560 m)的高节竹林竹笋,对竹笋外观品质、营养品质和食味品质指标进行调查测定。[结果]表明:海拔高度对高节竹笋基径、长度、笋个体质量、可食率和可溶性糖、维生素C、胱氨酸、酪氨酸含量、人体必需氨基酸比例及单宁、草酸含量有显著的影响(P0.05),对高节竹笋蛋白质、脂肪、淀粉、总黄酮、其它种类游离氨基酸、人体必需氨基酸含量和氨基酸总量及纤维素、木质素、苦味、鲜味、甜味氨基酸含量和甜味、鲜味氨基酸比例影响不显著(P0.05),对芳香味氨基酸含量和芳香味、苦味氨基酸比例有较显著的影响(P0.05)。[结论]海拔高度对高节竹笋外观品质有显著的影响,中、高海拔竹笋优于低海拔竹笋;海拔高度对竹笋营养品质、食味品质有较显著的影响,但对外观品质的影响更显著。 相似文献
14.
A nursery experiment was conducted to assess the effect of bioinoculants (Glomus aggregatum, Bacillus polymixa, Azospirillum brasilense) on seedling growth promotion of bamboo (Dendrocalamus strictus (Roxb.) Nees.) in two soil types (alfisol, vertisol) with or without fertilizer application. Bamboo seedlings were grown
in the presence or absence of bioinoculants either individually or in all combinations for 180 days in field soil under tropical
nursery conditions. Shoot, rhizome and root length, dry masses, nutrient concentrations and arbuscular mycorrhizal (AM) colonized
root lengths were determined at harvest. Under the experimental condition tested combined inoculation of AM fungi, PSB and
A. brasilense resulted in maximum growth response both under fertilized and unfertilized conditions in both soil types. Fertilizer application
enhanced the efficiencies of N, P and K uptake, whereas reduced their usage efficiencies. Though soil type did not affect
microbial inoculation response, fertilizer application significantly affected plant response to microbial inoculation. 相似文献
15.
We examined the effects of fencing on deer browsing on seedlings 13 years after the building the experimental fence on Mt.
Ohdaigahara, central Japan, where the sika deer (Cervus nippon) population is high. There was no difference in the species number of seedlings between 1991 and 2004. The density of seedlings
in the fenced plot in 2004 was three times higher than in 1991. Although the unfenced plots had no seedlings higher than 20 cm,
there were seedlings up to 120 cm in the fenced plot. These results suggest that 13-year fencing promoted regeneration of
seedlings in this area. 相似文献
16.
We investigated the mortality of post-dispersal seeds and current-year seedlings of a beech species (Fagus crenata Blume) at the northernmost extent of its geographical range at Utasai (Kuromatsunai), Hokkaido, Japan. Introduced seeds that
were protected from rodent predation by wire cages had a higher survival rate from winter to the following spring (mean ±
SD: 84 ± 16.7%,n = 10) than controls without cages (mean ± SD: 12 ± 17.9%,n = 10). Unprotected transplanted current-year seedlings with almost fully opened primary leaves never survived more than three
days (0%,n = 30), while more than 80% (n = 30) of seedlings within cages survived to the end of the growing season. These results indicate that rodent herbivory is
a major mortality factor that strongly prevents the establishment of beech seedlings. In a natural population, we observed
that 90% of seedlings (n = 197) disappeared within 10 days after their emergence and rodent herbivory caused this heavy mortality. A herbivorous rodent,
the gray-backed vole,Clethrionomys rufocanus bedfordiae, was remarkably abundant in late June (101.5 voles/ha), suggesting that this species strongly affects the formation of the
seedling bank. The presence ofC. rufocanus bedfordiae may be one of the reasons for the scarcity of beech seedlings and saplings and the rarity of recruitment in this northernmost
beech forest. 相似文献
17.
To clarify the establishment pattern of Cryptomeria japonica seedlings, the demography of current-year seedlings was studied under various micro-environmental conditions for 2 years in a cool-temperate old-growth forest in the snowy region of Japan. In both years, more than 70% of seedlings that emerged died within a year, and differences in the survival rate of seedlings with respect to micro-environmental conditions were similar. While a number of seedlings survived at the sites on fallen logs and in mineral soil, almost no seedlings survived at the sites with either broad-leaved or coniferous litters at the end of the first growing season. The negative litter effect may kill most small seedlings of C. japonica. In addition, we found that survival rates of the seedlings were greater as the distance from the nearest adult and canopy openness increased. An analysis using Quantification Theory I showed that, of the possible micro-environmental factors, substrate conditions had the strongest effect on the survival of seedlings. The analysis also indicated that distance from the nearest adult and canopy openness also affected seedling survival significantly and to almost the same extent, although the effects were weaker than those for the substrate condition. Given the limited establishment sites for C. japonica seedlings, layering is suggested to be the main mode of regeneration in this forest. 相似文献
18.
容器苗作为高效的育苗措施,可以显著地提高造林成活率。相对于1年生容器苗生长较弱、造林效果差的状况,2年生容器苗可改善造林效果。因此,针对南方红豆杉、浙江楠和浙江樟3种珍贵树种2年生大规格优质容器苗的培育需求,系统研究了缓释肥加载量对其生长、根系发育、生物量积累和分配以及N、P养分积累的影响。结果表明:(1)缓释肥加载量为1.5 kg·m-3时南方红豆杉地径达到最大值,2.5 kg·m-3缓释肥加载量能有效促进浙江樟苗高增长。缓释肥加载对南方红豆杉根、叶和总生物量积累具有显著影响;(2)南方红豆杉和浙江樟总根长、根体积和根系表面积均在3.5 kg·m-3缓释肥加载量下达到最大,而2.5 kg·m-3缓释肥加载量则可满足浙江楠根体积和根表面积的增长;(3)3.5 kg·m-3缓释肥加载量有助于3个树种2年生容器苗养分库中N素的积累,但较低缓释肥加载量(1.5 kg·m-3)利于浙江楠P素养分库的构建。养分含量的提高在一定范围内可促进容器苗生长和养分库中养分的积累,而养分含量过高不仅抑制容器苗生长,还会引起养分在苗木体内的再分配。综合考虑,建议对南方红豆杉和浙江樟2年生容器苗采用1.67 g·株-1 N素和0.74 g·株-1 P素的施肥水平进行培育,而培育浙江楠2年生容器苗宜采用1.67 g·株-1 N素和0.32 g·株-1 P素施肥水平。 相似文献
19.
Three VA-mycorrhizal fungi; Glomus occultum, Glomus aggregatum (local isolates) and G. mosseae (strain from Bangalore, India) were inoculated to assess their effect on growth of Acacia mangium in lateritic soil. All inoculations enhanced growth with respect to shoot height, root diameter, leaf area, chlorophyll content
and biomass of A. mangium significantly compared to uninoculated control seedlings. G. occultum proved most efficient among the three. The mycorrhizal dependency factor indicated that the growth of A. mangium was 57% dependent on G. occultum, 47% on G. mosseae and 46% on Glomus aggregatum. 相似文献
20.
Hiroki Itô 《Journal of Forest Research》2009,14(4):245-250
Seedling emergence and initial survival were compared for two evergreen broad-leaved species, Quercus glauca and Symplocos prunifolia. The relationships between the two seedling dynamics variables and environmental factors for the two species were also investigated.
The number of seedlings that emerged in the study period was larger for S. prunifolia than for Q. glauca, while the survival rate was lower for S. prunifolia, presumably due to the closed canopy of this site. Models were selected for each species to determine the combination of
variables explaining the most variation in emergence and survival of seedlings. The model selected for seedling emergence
of Q. glauca showed that more seedlings emerged in lower hillslope positions and where the canopy in winter was more open. The model selected
for S. prunifolia showed that fewer seedlings emerged on steeper slopes and that more emerged under a more open canopy in winter. With respect
to seedling survival, models with only the proportion of open canopy in summer were selected for both species. These models
showed that the survival rate was higher where the canopy in summer was more open. This is to be expected as both species
are regarded as pioneer or mid-successional species. Q. glauca seemed to have the ability to persist as a dominant in the secondary forest at this site for longer than S. prunifolia due to the former’s better seedling survival rates and the rarity of climax species such as Castanopsis cuspidata. 相似文献