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1.
We derived an allometric model of the height–diameter curve for even-aged pure stands, which was a modification of the earlier
model proposed by Inoue (2000a). An individual-dependent allometric equation was used as the height–diameter curve. Using
the discriminant analysis method, all trees composed of a stand were stratified into upper and lower trees. It was assumed
that both relationships between mean tree height H
m
and upper tree height H
u
and between mean DBH D
m
and mean DBH of upper trees D
u
could be described by the time-dependent allometric power equations. The height–diameter curve showed an average relationship
between tree height and DBH of a given stand at a given time, and hence it could be assumed that the height–diameter curve
contained two points (D
m
, H
m
) and (D
u
, H
u
). With these assumptions, we derived an allometirc model of height–diameter curve, which allowed the coefficients of the
curve to be estimated from mean tree height and mean DBH. The proposed model was fitted to Japanese cedar (Cryptomeria japonica D. Don) data. The error ratio of the allometric model ranged from 2.254% to 13.412% (mean = 6.785%), which was significantly
smaller than that of the earlier model. When the error of mean tree height was ±1.0 m or less, the effect of the error of
mean tree height on the error ratio was comparatively small. This suggested that the error of ±1.0 m in mean tree height could
be accepted in the estimation of height–diameter curve using the allometric model. These features enable us to combine the
allometric model with Hirata’s vertical angle-count sampling or growth models. In conclusion, the allometric model would be
one of the most practical and convenient approaches for estimating the height–diameter relationship of even-aged pure stands. 相似文献
2.
Carbon sequestration in the woody biomass of shelterbelts has been investigated but there have been no measurements of the
C stocks in soil and tree litter under this agroforestry practice. The objective of this study was to quantify C stored in
surface soil layers and tree litter within and adjacent to a 35-year-old shelterbelt in eastern Nebraska, USA. The 2-row shelterbelt
was composed of eastern red cedar (Juniperus virginiana) and scotch pine (Pinus sylvestris). A sampling grid was established across a section of the shelterbelt on Tomek silt loam (fine, smectitic, mesic Pachic Argiudolls).
Four soil cores were collected at each grid point, divided into 0–7.5 and 7.5–15 cm depth increments, and composited by depth.
Soil samples were analyzed for total, organic, and inorganic C, total N, texture, pH, and nutrient content. Under the shelterbelt,
all surface litter in a 0.5 × 0.5 m2 area at each grid point was collected prior to soil sampling, dried, weighed, sorted, and analyzed for total C and N. Average
soil organic carbon (SOC) in the 0–15 cm layer within the shelterbelt (3,994 g m−2) was significantly greater than in the cultivated fields (3,623 g m−2). The tree litter contained an additional ∼1,300 g C m−2. Patterns of litter mass and soil pH and texture suggested increased organic inputs by tree litter and deposition of wind-blown
sediment may be responsible for greater SOC beneath the shelterbelt. Further research is needed to identify the mechanism(s)
responsible for the observed patterns of SOC within and adjacent to the shelterbelt and to quantify the C in biomass and deeper
soil layers.
相似文献
| Thomas J. SauerEmail: |
3.
Tomohiro Nishizono Fumiaki Kitahara Toshiro Iehara Yasushi Mitsuda 《Journal of Forest Research》2014,19(3):305-316
In this study, we analyzed Japanese National Forest Inventory data to investigate the geographical variation in the relationship between tree height and age for dominant trees, and the effects of climatic conditions on these relationships. Our analysis focused on Cryptomeria japonica forests in 13 regions of Japan. The age–height relationships were classified into two regional groups that were distinguished by their climatic conditions. Several categories of climatic variables (warmth, solar radiation, precipitation, and snow depth) were significantly correlated with the parameters of a model for the age–height relationships. Our results also suggest the existence of a latitudinal cline for the maximum tree height of C. japonica in Japan. In regions with cold temperatures, deep snow, low solar radiation, and low summer precipitation, C. japonica shows a late-maturity pattern for height increase, with slow initial growth and a large maximum size. In regions with the opposite climatic conditions, it shows an early-maturity pattern with fast initial growth and small maximum size. 相似文献
4.
Yuko Ota Megumi K. Kimura Tsutomu Hattori Yurika Miyuki Ryota Endo 《Journal of Forest Research》2016,21(2):105-109
Trunk rot, caused by Fomitiporia torreyae, is one of the most economically important sap rot diseases on Cryptomeria japonica, especially on a cutting cultivar ‘Sanbu-sugi’. This disease had been reported only from Chiba and Ibaraki prefectures in Japan; however, a similar trunk rot on Japanese cedars was found recently in Kyoto prefecture. We identified the causal agent of the trunk rot on Japanese cedars in Kyoto prefecture, clarified the genotype of ‘Sanbu-sugi’ (sensu stricto) using microsatellite markers, and then investigated the relatedness of these infected cedars with ‘Sanbu-sugi’. The pathogen was identified as F. torreyae by its DNA sequences and morphological characteristics of the fruiting body. The 25 ramets of ‘Sanbu-sugi’ had only one genotype based on eight microsatellite loci. Infected Japanese cedars in Kyoto were comprised of different genotypes and showed no close relatedness to ‘Sanbu-sugi’. This is the first report of trunk rot caused by F. torreyae on cultivars of Japanese cedar with no relatedness to ‘Sanbu-sugi’ outside of Chiba and Ibaraki prefectures and showed the potential for expansion of this disease to Japanese cedar plantations in other areas. 相似文献
5.
6.
Yoshie Terashima 《Journal of Wood Science》2013,59(1):80-87
An unidentified Fomitiporia sp. causes severe white-rot on stems of a cultivar “Sanbu-sugi” of the Japanese cedar, Cryptomeria japonica. The influence of the fungus on tree health and wood properties was determined. Bark from dead branches and xylem from living branches contained more glucose than bark from living branches and xylem from dead branches. Tree heights at which annual rings were disconnected were 2, 4 and 6 m at ages 37, 15 and 24 years old, respectively. The pH values of damaged parts were lower than those of non-damaged parts, and the damaged parts were clearly identified using bromocresol green solution. Weight loss of sapwood during 60 days of fungal degradation was 1.4 %, which was less than that by a saprophyte, Trametes versicolor. The amount of polyphenols in the heartwood from damaged tree stems was less than that from non-damaged stems. Degraded parts were less stiff than the non-degraded sapwood as measured with a wood-decay tester, Pilodyn. Our observations indicate that damaged stems are chemically and physically inferior to non-damaged stems. 相似文献
7.
Naoko Yamaguchi Susumu Shiraishi Yoshinori Sasaki Chiaki Yamamoto 《Journal of Forest Research》2000,5(1):35-38
Leyland cypress (×Cupressocyparis leylandii) has been regarded as an intergeneric hybrid between Monterey cypress (Cupressus macrocarpa) and Alaska cypress (Chamaecyparis nootkatensis) in the Cupressaceae. Each partial sequence of the 18S-rDNA from nuclear and therbcL from chloroplast DNA genomes was determined using above three species. At the 59th site from the 5′ end of the 152 bp of
the determined 18S-rDNA sequence, one base difference was identified between Monterey cypress (T) and Alaska cypress (A). However, Leyland cypress
showed either nucleotide A or T at this site. Since nuclear DNA is inherited by biparental mode, this result shows genetic
evidence that the nucleic genome of Leyland cypress originates from Monterey cypress and Alaska cypress and that this species
is of hybrid origin. 相似文献
8.
Intercultural studies about the methods of use and perceptions of traditional remedies in Europe are strategically important in understanding how pharmaceutical means in our multicultural modern societies are differently accepted by diverse ethnic groups. In this survey, we analysed the biological means traditionally used in the ethnomedicine of three Arb?resh? (ethnic Albanians) communities in the Vulture area (northern Lucania, southern Italy). The majority of remedies are represented by plants belonging to 54 botanical taxa. A few of the recorded species have a traditional therapeutic use that has never previously been reported in southern Italy. Other means-especially used in the past-are comprised of mineral, animal and industrial derived materials. In specific cases, some of these materials and even plants are neither applied externally or internally, but are instead utilised as symbolic ritual objects in spiritual healing ceremonies. Ethnopharmacological and anthropological considerations about these usages are discussed. 相似文献
9.
《林业与社会》2000,(2)
ItiswellknownthatthecharacteristicsofChina'ssituationsareoverpopulation,poorfoundation,lowculturalandscienceandtechnologylevels,lackandunevendistributionofresources,andlowrankingofpercapitaGDP.Owingtothebackwardofscienceandtechnologyandmanagement,therelativelyshort-suppliedresourceshasnotbeenutilizedproperly.Takingforestryforexample,thecoverisonly13.92%,lowerthantheworld'saverageof22%;China'spercapitaaverageofforestlandislessthan0.13ha,whiletheworld'saverageis1.lha;Chinaisalsolowinforestqual… 相似文献
10.
Cao Jin-zhen Li Li-dan Liu Zhi College of Materials Science Engineering Beijing Forestry University Beijing P. R. China 《中国林学(英文版)》2005,7(4)
In this study, the contact angles of three different reference liquids (including distilled water, diiodomethane, and formamide) and PF resin on the surfaces of Chinese fir (Cunninghamia lanceolata) samples untreated or treated with different con- centrations of ACQ-D (ammoniacal copper quat Type D) solutions were measured. Then, the surface free energy was calculated by two approaches: acid-base approach and geometric mean approach. ACQ-D treatment caused higher contact angles and lower surface free energies at a retention level corresponding to the commodity treated wood products. When wood was treated with much higher concentrations of ACQ-D, the total surface free energy of wood would be higher than the untreated control. Acid-base/polar compo- nents related with the hydrogen bonding state in wood were considered to be responsible for the observed changes according to the applied approaches. The hydrophobic properties and also higher contact angles of PF resin drop on wood surfaces after ACQ-D treatment at a reasonable retention level confirms the changes on surface free energy. 相似文献
11.
The hormone combinations and dark culture of the callus induction for Cyclocarya paliurus (Batal.) Iljinskaja leaves were 相似文献
12.
The title compounds 4,4'-oxobis(propham) ((?)n) (C20H24N2O5, Mr.=372.41) was synthesized by the addition reaction of corresponding 4,4'-oxobisphenyl diisocyanate with isopropanol. The crystal structure was determined by X-ray diffraction method. The crystal is triclinic system, space group P-1 with a=8.5107(17), b=9. 1164(18), c=14.5701(3)A, α=80.44(3),β=85.25(3), γ =62.88(3)°, V=992.2(3)A3, Z=2 , Dc=1.247g/cm3, F (000)=396, R =0.0520 , wR2=0.1434 for 4336 observed reflections with [I>2 σ(I)]. X-ray analysis reveals that interatomic distances for O(2)-C(7) is 1.2142(19), O(4)-C(17) is 1.2136(18)A, obviously show they form C=O double bonds. 相似文献
13.
Artificial Incubation of Great Bustard (Otis tarda) Eggs 总被引：1，自引：0，他引：1
IntroductionGreatbustaFd(OtiSteeds),oneoftheendangeredbiEdsintheworld,wasdefinedasfirstrankproteCtedanimalinChinaitisestimatedthatabout2000-3000individualsaresurvivinginChina.ArtificialincubationisoneoftheimportantwaytorestoreandsavesuchendangeredspeciesasgreatbustaFd.But,noreportswerefoundonincubationofgreatbustardindomestic.During1995-1997,weconduCtedtheexperimentonartificialincubationofgreatbustaFdegg.MaterialandMethodSourceofeggsTheexperimentaleggsforartificialincubationwerecollected… 相似文献
14.
The possible horizontal transfer of transgenes is of great concern when the transgenic plants are released into the field. To test the possible transfer of nptⅡ of transgenic trees into soil bacteria, we have used a stool DNA preparation kit to isolate the DNA from the soils in the rhizospheres of two non- and eight transgenic Eucalyptus camaldulensis trees. All the samples have provided the corresponding PCR products in the amplification with bacterial 16S RNA specific sequences, which indicates that the quality of the isolated DNA is adequate for amplification. The nptⅡ specific band has been amplified in three soil samples from the transgenic trees and even treated with filtration before the DNA isolation. This indicates that nptlI DNA exists in the soil, although it is still unclear whether the DNA was in the soil particles, in the soil bacteria or in the Agrobaeterium contamination which was used for the E.camaldulensis transformation. Two approaches on isolation of bacterial DNA have been suggested for testing the possibility of this event in the future. 相似文献
15.
16.
《Journal of Sustainable Forestry》2013,32(3-4):33-43
Abstract Fewer than one tenth of tropical forests are being managed on a sustainable basis. Sustainable forest management means managing the forest in such a way as to not irreversibly reduce the potential of that forest to produce all products in subsequent harvests. The United Nations Conference on Environment and Development in Rio resulted in several decisions that are relevant to the future of forestry. The Conference also focused world attention on questions of the environment. One outcome of this increased awareness has been the growing support for eco-labelling, which may provide an opportunity for those countries able to prove their forest products are harvested sustainably. Other economic opportunities present themselves in the utilization for cellulose of tree crops such as rubberwood and oil palm trunks and fronds. Non-wood resources such as rattan also hold promise if we are able to grow them in conjunction with existing tree crops. The roles of tropical forests as carbon sinks require more in-depth study as does the question of what constitutes critical levels of biodiversity. Aesthetic values such as recreational use increasingly require that sufficient buffer zones of unique features be preserved. These challenges demand that the forestry profession becomes more proactive and support major policy changes to address the need for sustainable forest management. 相似文献
18.
19.
The study was conducted in the Solan Forest Division with an area of 57,158 ha in Himachal Pradesh to study spatial distribution of plant biodiversity. The forest division has an altitudinal gradient from 600–2,260 m amsl. The contours on the Forest Survey of India (FSI) topo sheets (1:25000 scale) for this division were digitized to generate its Digital Elevation Model (DEM). It was stratified into five elevation classes (600–900, 900–1,200, 1,200–1,500, 1,500–1,800, 1800 m and above). A stock map of the division was digitized and superimposed on stratified DEM to know the distribution of vegetation at different elevations. Eight types of land use covers recorded in this division are: (a) chir pine (Pinus roxburghii) forests, (b) bamboo (Dendrocalamus strictus) forests, (c) khair (Acacia catechu) forests, (d) ban oak (Quercus leucotricophora) forests, (e) deodar (Cedrus deodara) forests, (f) broad leaved forests, (g) cultivation, and (h) culturable blank. Around 16.50% of the division's area was estimated to be under different land uses. Total biomass of vegetation in different land uses of the division is estimated as 63.80?×?104 tons. Total carbon stock of the division was 11.71?×?105 tons. Biomass density and carbon density were found to increase with elevation. 相似文献
20.
The univoltine psyllid Cacopsylla picta (Foerster) is the main vector of ‘Ca. Phytoplasma mali’ in Germany, the causal agent of apple proliferation, an economically important disease of apple in Europe. Its population dynamics on its host plant apple (Malus spp.) and migration to coniferous shelter plants for overwintering have been described for Southwest Germany. Temporary greenhouse rearing under controlled conditions, starting from field-collected overwintered adults, was set up to produce homogeneous offspring. New generation adults were transferred to conifers in the greenhouse at the beginning of the natural migration phase to obtain a continuous rearing spanning the aestivation and hibernation period. However, efforts to directly overwinter C. picta on different conifer species failed. The natural overwintering sites were therefore identified and their climatic conditions, mainly moderate summer temperatures with increased humidity and natural cold winter conditions including frost were reproduced. Teneral individuals of the new generation did not switch instantaneously from host plants to conifers. Successful overwintering under experimental conditions was only achieved using a gradual host plant transfer. By incorporating these key factors two continuous rearings of C. picta were maintained over 3 years with both, spruce and pine, as suitable shelter plants. This is the first report of a permanent rearing of C. picta under experimental conditions. Our data show experimentally that C. picta is univoltine and that conifers act only as shelter plants for overwintering and not as hosts for reproduction. 相似文献