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1.
Rapid early growth of tree seedlings is critical to the success of plantation establishment. We investigated the effects of
seedling size (small and large) and container types (small [Lannen 121], medium [Lannen 81] and large [Forestry Tube]) in
the nursery and the effects of mammal browsing after planting on growth of Eucalyptus globulus in Tasmania’s Southern Forests. After planting, seedlings were either exposed to browsing or protected from browsing by wire-mesh
cages until age 6 months. Low browsing pressure resulted in around 20% and 5–10% of foliage being browsed in the large and
small size categories, respectively, between 1 and 3 months after planting the uncaged treatment. 6 months after planting,
height growth increment was lower, and 4 years after planting, mortality was higher in uncaged large than caged large seedling
treatments. Six and twelve months after planting, seedlings raised in Forestry Tube containers had significantly greater height
increment and root collar diameter relative to other treatments. By 4 years after planting, trees of the small seedling treatment
had significantly greater diameter than those of the large seedling treatment, but there was no effect of container type treatment.
Four years after planting there was no effect on diameter growth by browsing of <30% of foliage up to 3 months after planting,
although there was greater incidence of double leaders in trees that had been browsed as seedlings. Small seedlings produced
more growth 4 years after planting than large seedlings of E. globulus. 相似文献
2.
Arne Sæbø Inger Sundheim Fløistad Jan Netland Brynjar Skúlason Øyvind Meland Edvardsen 《New Forests》2009,38(2):143-156
Abies nordmanniana and Abies lasiocarpa, established for Christmas tree production in southwestern Norway (58°44′N, 5°38′E), were treated with different weed control
methods, including chemicals, use of black plastic mulch, grass or clover as ground cover, living mulch and mechanical hoeing.
Ground cover with black plastic mulching resulted in the best growth and quality in A. lasiocarpa; the least favourable treatment was when grasses were allowed to grow close to the trees. Unless measures were taken to remove
this competing vegetation, the ground cover grew over the trees, smothering 94% of them. A. nordmanniana plants grew to the same height on plots with no weed control as on plots with thorough weed eradication. Stem diameter decreased
on plots with ground vegetation compared to seedlings grown in the weed-free environment. The use of Trifolium repens as ground cover decreased height growth by 30% compared to thorough weed control. Both grasses and clover sown as living
mulch, damaged the trees more than did natural weed vegetation. 相似文献
3.
The effect of herbaceous vegetation on growth and survival was assessed in planted eucalyptus saplings grown under four levels
of weed cover. Seedlings of Eucalyptus globulus subsp. maidenii were planted with 0 (W0), 25 (W25), 50 (W50) and 100% (W100) weed cover. Weed species composition and aboveground biomass
was determined. Soil water content was evaluated by the gravimetric method. Seedling leaf area, diameter and height were evaluated
at planting and during the 3 months following establishment. Tree height, diameter and stem volume was estimated at 12, 24
and 36 months. First year tree survival was recorded. The ratio of cumulative stem growth under W100: cumulative stem growth
under W0 was used to measure competitive performance. Regression analysis was used to determine competition thresholds. Weeds
seriously threaten the growth of E. globulus subsp. maidenii. Early negative effects of competition on growth were evident as from the second month after establishment, and both seedlings
and 1-year-old saplings were more affected than 2- and 3-year-old ones. A “minimum-response threshold” was determined near
500 kg/ha (corresponding to W25 cover). No clear effect was found between sapling survival and weed biomass. 相似文献
4.
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• We aimed to better understand the genetic architecture of growth in E. globulus undergoing inbreeding by comparing families from selfing (SELF), open pollination (OP) and unrelated polymix crossing (POL)
of common parents. Stem diameter at breast height (DBH) was assessed at 4, 6 and 10 years after planting in a field trial. 相似文献
5.
Brenda Colleen Clifton-Cardoso Marcelo Schramm Mielke José Roberto De Melo Rondinele Nascimento Querino 《New Forests》2008,35(1):15-31
Dimorphandra jorgei MF Silva (Caesalpinaceae) and Swartzia macrostachya Benth. var. riedelii Cowan (Fabaceae) are tree species from the southern Bahian Atlantic Forest, identified for the restoration of degraded areas.
The objective of this research is to study their seed germination and seedling growth to develop simple methods for seedling
production in small scale nurseries. Because the species have distinct dormancy and germination characteristics, the seeds
were submitted to different treatments. D. jorgei seeds were immersed in hot water, scarified and stored for 12 weeks in the laboratory environment (25°C). S. macrostachya seeds were submitted to different combinations of drying and storage in the laboratory environment or refrigerator (4°C).
Seedlings were submitted to two light treatments for 3 months: partial shade (52% of full sun) and full shade (12% of full
sun). In D. jorgei, the highest germination occurred for scarified seeds (87%) and for seeds stored for 12 weeks and then scarified (69%). In
S. macrostachya the undried control seeds had the highest germination, followed by that of the refrigeration storage treatment, without predrying
(99% and 97%, respectively). The average values for the growth parameters were greater in full shade for D. jorgei, while S. macrostachya seedlings showed greater growth rates in partial shade. Two months growth is recommended before D. jorgei seedlings are of the sufficient size and leaf number for field planting. On the other hand, a period of 4 months is recommended
for S. macrostachya, due to its relatively slow growth. 相似文献
6.
Masako Kubo Koji Shimano Hitoshi Sakio Yuji Isagi Keiichi Ohno 《Journal of Forest Research》2010,15(5):337-340
Cercidiphyllum japonicum and C. magnificum are deciduous tree species that produce large numbers of sprouts. They are found mainly in riparian and/or disturbed areas.
C. japonicum is distributed in the montane zone in Japan, whereas C. magnificum is distributed mostly in the subalpine zone of central Japan. However, the two species sometimes coexist, e.g., on the talus
slope at the valley head of the Chichibu Mountains. We investigated differences in sprouting traits in these two species by
comparing class distributions of sprout diameter at breast height (DBH) and heights of individuals on the talus slope. Sprout
DBH and individual height were smaller in C. magnificum as compared to C. japonicum. Moreover, the analysis of the DBH-class distribution of each species indicated that C. magnificum had numerous small sprouts and experienced high mortality, whereas C. japonicum had fewer small sprouts and low mortality. It is likely that the sprouting traits of C. magnificum make it more adapted to severe conditions in the subalpine zone than those of C. japonicum. 相似文献
7.
David Paul Blackburn Matthew G. Hamilton Chris E. Harwood Trevor C. Innes Bradley M. Potts Dean Williams 《Annals of Forest Science》2011,68(7):1187-1195
• IntroductionThere is increasing interest in managing Eucalyptus nitens plantations for sawn timber production. 相似文献8.
Juan Valencia Chris Harwood Russell Washusen Andrew Morrow Matthew Wood Peter Volker 《Wood Science and Technology》2011,45(1):15-34
Peripheral longitudinal growth strain (LGS) was measured on a total of 81, 22-year-old pruned Eucalyptus nitens trees from five thinning treatments in a plantation thinning trial in Tasmania. Growth strain data were gathered at breast
height on each tree using the CIRAD-Forêt method. The effects of thinning treatment and tree diameter on LGS and its relationships
to solid-wood traits determined in a processing trial were examined. LGS was significantly higher in the direction of the
prevailing wind and was not significantly affected by either thinning treatment or tree diameter. An index of log end splitting
was positively related to tree diameter, sawlog position (upper/lower), and LGS, which explained up to an additional 20% of
the variance after tree diameter and log position were accounted for in a linear regression model. High LGS and log end splitting
were significant indicators of increased board end splitting. 相似文献
9.
Natural forests have been increasingly replaced by artificial plantations around the world. Some research results suggest
that artificial plantations can promote natural regeneration. The efforts in establishing protective forests in Hong Kong
over the last 50 years after the Second World War have resulted in many exotic tree plantations which are ideal sites for
the study of natural regeneration. This study looked at the seed rain and understorey woody plant diversity in three Lophostemon confertus plantations (25–40 years old) in Hong Kong. All the plantations were > 1 km from the nearest seed sources. Two of the plantations
had a seed rain comparable in density and diversity to unplanted grasslands, and the understorey plant diversity was also
low and dominated by shrubs. The other site had a higher and more diverse seed rain, as well as higher understorey stem density,
but both the seed rain and the understorey were dominated by the shrub Psychotria asiatica. The poor seed rain at two sites and the rarity of potential canopy tree species in both the seed rain and understory regeneration
at all sites suggest that planting exotic monocultures does not promote succession. Enrichment planting will be needed to
restore forest diversity. 相似文献
10.
Young trees were harvested to explore non-destructive methodologies to estimate live branch dry weights in young fast-growing Eucalyptus species under different spacing and fertilizer treatments. Branch growth can vary with silvicultural management such as spacing, fertilizing and thinning, and over relatively short periods in response to environmental conditions. Many published regressions based on standard measurements of height and diameter are site, age and treatment specific. The aim of this study was to improve our capacity to predict woody crown dry weight, based on stem measurements, and to minimize (or eliminate) treatment effects on the resulting model. In young trees, branches are temporary support structures for foliage and are often discarded as the base of the green crown rises. As temporary structures they represent an investment of biomass and nutrient elements, and are subject to selection pressures to maximize the return on investment by the tree. Trees were harvested from existing plantation experiments located in south-eastern Queensland for E. grandis W. Hill ex Maiden (ranging from 0.28 to 15.85 m in height, to 5 years old) and south-western Australia for E. globulus Labill. (0.10–34.4 m in height, to 10.2 years) in order to examine the impact of spacing, nitrogen and phosphorus fertilization on early growth. Relationships to estimate crown woody biomass from non-destructive measurements were developed, and these relationships tended to have different slopes and intercepts for trees with predominantly juvenile foliage and those with intermediate or adult foliage. Dry weight of whole-crown live branch wood (Wbranch) was related to heights and/or diameter at breast height (DBH), but the regressions parameters were different, depending on treatment. The relationships became more generic (i.e. less dependent on treatment effects) between Wbranch and stem sectional area at the height of the base of the green crown (SACB), consistent with the pipe model theory (R2 > 0.91 for the two species for trees with intermediate/adult leaves). However, Wbranch was more closely related again to the stem volume above the base of the green crown and treatment effects were not significant (VCon,gc, R2 > 0.93). Branches exit the stem below the green crown, and for E. grandis the best relationship was on stem volume above the lowest live branch (VCon,llb, R2 0.94). Limited sampling from four other species with similar or contrasting crown characteristics indicated that the relationship could be applied quite generally. Individual E. grandis branch woody dry weight was closely related to the conical volume of the main (first order) branch (Vcon,br, R2 0.98). The whole crown equivalent, branch woody dry weight plus stem dry weight above the lowest live branch, was also closely related to the stem volume within the woody crown (VCon,llb, R2 0.97–0.99). While the slope of this relationship was still significantly different between trees with juvenile and intermediate/adult foliage, it had a similar form, suggesting that trees with juvenile foliage allocated a different proportion of their woody biomass within the crown to branches than older trees. 相似文献
11.
Generic equations are proposed for stem, branch and foliage biomass of individual trees in even-aged pure stands of Cryptomeria japonica, Chamaecyparis obtusa and Larix kaempferi. Biomass data was collected from a total of 1,016 individual trees from 247 stands throughout Japan, and five regression
models were assessed by root mean square error, mean bias, fit index (FI), and AIC. The results show that a power equation
using diameter at breast height (dbh) and height is the most suitable for all species and components. This equation is more
accurate than the familiar power equation that uses ‘dbh2 height’, and it expresses the greater volume of branch and foliage mass of trees with a lower height/diameter ratio. A power
equation using dbh is more reasonable for models with dbh as the only independent variable and more accurate than a power
equation using ‘dbh2 height’ for estimating branch and foliage mass. Estimating error for branch and foliage mass is larger than that for stem
mass, but the entire aboveground biomass can be estimated with an error of less than 19%, except in the case of small trees
with dbh less than 10 cm. 相似文献
12.
Competition control is essential for successful eucalyptus plantation establishment, yet few selective herbicides have been identified. Five herbicides, flumioxazin, imazamox, imazapic, oxyfluorfen, and sulfometuron methyl, were evaluated at either pre- or post-weed emergence timing for selective weed control in the establishment of Eucalyptus benthamii, a frost-tolerant species showing promise for commercial plantations in the southeastern United States and southern Brazil. Herbicides were applied at two or three rates and compared to a non-treated control and to near-complete weed control obtained with repeated glyphosate directed sprays. Herbicides were most efficacious when applied prior to weed emergence, at 2 weeks after planting 16-week-old containerized eucalyptus seedlings. Pre-emergence imazapic treatments resulted in broad-spectrum and persistent weed control, with 77–82% bare-ground at 60 days after treatment, but both pre- and post-emergence applications of imazapic caused excessive eucalyptus injury at the highest rate tested. Imazapic, sulfometuron, and imazamox were most effective for grass control. Both timings of flumioxazin were effective for forb control at the early assessment. All pre-emergence treatments enhanced stem volume compared to the non-treated control, but post-emergence treatments did not, suggesting the need for early weed control to facilitate E. benthamii growth. Pre-emergence applications of medium and high sulfometuron, low imazapic, high imazamox, and high oxyfluorfen rates increased stem volume four-fold to six-fold compared to the non-treated control. Repeated glyphosate directed sprays increased stem volume nearly three-fold compared to the control. These results confirm one early report of flumioxazin effectiveness and identify imazamox and imazapic as new selective herbicides for eucalyptus culture. 相似文献
13.
A. C. Madeira M. Madeira A. Fabião P. Marques M. Carneiro 《European Journal of Forest Research》2010,129(4):591-601
Growth and nutritional status of young plants of Eucalyptus were assessed in a field trial, under different scenarios of harvest residue management and nutrient availability. Treatments
were as follows: incorporation of harvest residues into the soil by harrowing (I); I with N fertiliser application (IF); I
with leguminous, Lupinus luteus L., seeding (IL); removal of harvest residues (R); R with N fertiliser application (RF); R with leguminous seeding (RL);
distribution of harvest residues on the soil surface (S); S with N fertiliser application (SF). Treatments were replicated
four times in four blocks with a fully randomised design. Tree growth (height and diameter at breast height) was measured
and understory biomass destructively recorded. Tree nutritional status was assessed by foliar analysis (N, Ca, Mg, P, K and
leaf area). Significant differences in growth between I, R and S treatments were only detected at early stage. Intercropping
with Lupinus decreased tree growth during the early phase, but after 5 years growth was similar to that measured in the I and R treatments.
Application of fertiliser enhanced tree growth especially when harvest residues were retained on the soil surface. Combining
incorporation of harvest residues with fertiliser application (IF) was the best option to increase tree growth, which was
significantly greater than in the R and S. Initially, leaf N was positively affected by the leguminous (RL and IL), but, after
the first fertiliser application (1 year after planting), greater N was observed in the IF, RF and SF, the difference decreasing
gradually over the following years. 相似文献
14.
D. S. Thomas 《New Forests》2009,38(3):245-259
Forestry requires low mortality of transplanted seedlings. Mortality shortly after planting is often associated with inadequate
hydration of transplants. Seedlings can be hardened to the drought conditions they may experience after transplanting by exposing
them to controlled drought conditions in the nursery. Eucalyptus pilularis Sm. seedlings were drought hardened by providing nil (severe treatment) or half (mild treatment) the daily irrigation routinely
received (control treatment) for up to two non-consecutive days per week during the last 4 weeks of growth in the nursery.
Drought hardening reduced stem diameter, seedling leaf area, leaf area per root biomass and seedling quality measured by the
Dickson quality index, but increased root:shoot ratio. Hardened seedlings had lower stomatal conductance and leaf water potential
on the days they received less irrigation that the control treatment. Hardened seedlings had greater stomatal conductance
and were less water stressed than seedlings experiencing drought for the first time indicating hardened seedlings had adjusted
physiologically to drought. Survival after transplanting in the controlled drought environment in a glasshouse was enhanced
by the hardening treatments. Non hardened seedlings that had had their upper leaves manually removed immediately prior to
transplanting to reduce leaf area (top-clipped) had similar survival to hardened seedlings. Stomatal conductance and leaf
water potential after transplanting were higher in hardened and top-clipped seedlings than unhardened control seedlings or
vegetative cuttings. Survival in the field trial was over 95% for all treatments, possibly as rain fell within 4 days of planting
and follow-up rain occurred in the subsequent weeks. Neither the hardened or top-clipped seedlings planted in the field trial
had reduced growth, increased propensity to form double leaders or worse stem form than control seedlings when measured at
age 3 years. 相似文献
15.
Maman?Turjaman Yutaka?Tamai Hendrik?Segah Suwido Hester?Limin Joo Young?Cha Mitsuru?Osaki Keitaro?Tawaraya
Trees of the family Dipterocarpaceae are the dominant trees in Southeast Asian tropical forests where they play an important ecological role and are also important commercially. An experiment was conducted to determine the effect of ectomycorrhizal fungi on the growth of dipterocarp species in peat soils. Seedlings of Shorea pinanga were inoculated with spores of two ectomycorrhizal fungi, Pisolithus arhizus and Scleroderma sp. were grown in pots containing sterilized peat soil for 7 months. The percentage of ectomycorrhizal colonization on S. pinanga exceeded 86%. Colonization of S. pinanga roots by ectomycorrhizal fungi resulted in increased shoot height, stem diameter, number of leaves, and shoot fresh and dry weight. Survival rates of S. pinanga were greater for inoculated seedlings than control seedlings. These results suggest that inoculation of ectomycorrhizal fungi can improve the early growth of S. pinanga grown in tropical forests and that this technique will accelerate the rehabilitation of degraded dipterocarp forests. 相似文献
16.
Six endophytic bacterial strains from wheat roots, selected from extensive screening tests, were studied in greenhouse pot
experiments against take-all disease of wheat, caused by Gaeumannomyces graminis var. tritici (Ggt). For comparison, the fungicide triadimefon was included. All six bacterial strains and triadimefon significantly reduced
take-all in wheat plants between 39.4 and 57.3% compared to the inoculated control. Treatment with the bacterial strains also
significantly increased growth parameters of roots (e.g., average length, fresh, and dry weight) in comparison with the inoculated
control. One of the endophytic bacterial strains, designated EDR4, which proved to be most consistent in further greenhouse
tests, was also examined in field trials against take-all in wheat. In the field experiment 2006/2007, height of wheat plants
in Ggt inoculated plots was significantly reduced compared to the non-inoculated treatments. Yield parameters such as kernels
per head and thousand kernel weight (TKW) in the inoculated control were lower compared to other treatments. In the inoculated
plots, individual treatments with the strain EDR4 increased yield compared to the inoculated control. In the field trial 2007/2008
treatments with strain EDR4 as well as the fungicide triadimefon reduced take-all by 49.6 and 61.9%, respectively, compared
to the inoculated control. At harvest, in the inoculated control plant height, seeds per head and TKW were significantly lower
compared to the other treatments. Treatments with EDR4 eliminated the detrimental effects of take-all on grain yield to a
similar degree as triadimefon application. The strain EDR4 distinctly inhibited growth of Ggt in vitro and was identified
as Bacillus subtilis on the basis of its morphology and 16S rRNA sequence analysis as well as physiological and biochemical characteristics. These
results indicate that the strain EDR4 has potential in directly controlling take-all disease of wheat. 相似文献
17.
Spatial pattern of recruitment is an important factor influencing population dynamics of plant communities. The spatial pattern is determined by seed dispersal and by the spatial variability of germination and initial survival. In the process of forest expansion following farmland abandonment, mid- and late-successional species are often dispersed in pioneer forests by birds. This could result in an aggregated spatial pattern of seeds that could influence the dynamics of these species in mixed pioneer forests. In the sub-Mediterranean area, mid- and late-successional species such as Quercus pubescens (downy oak) and Fagus sylvatica (European beech) are expected to replace pioneer Pinus species. Using a point sampling method we demonstrated that beech and oak seedlings (height <2 m) have a clumped distribution in the understorey of pine. This could result from an aggregated dispersal by jays (dispersal effect) or from preferential recruitment in particular habitats (habitat effect). To test these hypotheses we proposed a statistical analysis of spatial patterns of regeneration of beech and oak. Ground cover variables (i.e. cover by rock outcrops, herbs, box shrubs, mosses or pine) did not differ significantly around seedlings as compared with random sample plots. Likewise, clumped seedlings had growth similar to isolated seedlings, thus refuting the hypothesis of preferential location in the most favourable microsites. Aggregated dispersal seems to be involved in the process of regeneration. Since beech and oak seedlings have contrasting ecological demands, we discuss the implication of this pattern for the replacement dynamics of pine by these species. 相似文献
18.
Andrea Nesci Analía Montemarani María A. Passone Miriam Etcheverry 《Journal of pest science》2011,84(1):107-115
The purpose of this study is to investigate the insecticidal activity of two benzoic acids 2(3)-tert-butyl-4 hydroxyanisole (BHA) and 2,6-di(tert-butyl)-p-cresol (BHT); two phenolic acids 3-phenyl-2-propenoic acid (CA) and trans-4-hydroxy-3-methoxycinnamic acid (FA); and two essential oils of Eugenia caryophyllata (clove tree) and Thymus vulgaris (thyme) against Oryzaephilus surinamensis (L.) vector carrier of aflatoxigenic fungi on stored peanut. The weight loss of peanut, susceptibility of insects, Aspergillus isolation frequency from insects and peanut, and aflatoxin B1 analyses from peanut were determined. BHA, BHT, and BHA/BHT mixture were highly effective against O. surinamensis, these chemical agents give 100% mortality at the doses assayed. Essential oil of thyme at 2,000 and 3,000 ppm were highly
effective against O. surinamensis, these concentrations gave 100% mortality. No Aspergillus section Flavi contamination was observed in dead insects collected from peanut treated with BHA/BHT mixture. No differences were observed
in the fresh weight of pods peanut among treatments with and without chemical agents. All samples of treated peanut pods showed
complete inhibition of this toxin after 120 days of storage. Our results indicate that these substances could be evaluated
further for the control of pest vectors of aflatoxigenic fungi of stored peanut. 相似文献
19.
The antitermitic activities of leaf oils and their constituents, taken from three clones of Eucalyptus camaldulensis Dehnh. in Thailand, against Coptotermes formosanus Shiraki were investigated in contact and noncontact tests. The termiticidal mechanism was also examined. Antitermitic tests
demonstrated that E. camaldulensis leaf oils were both contact toxicants and fumigants to C. formosanus with LC50 values ranging between 12.68 and 17.50 mg/g by the contact method, and between 12.65 and 17.50 mg/petri dish (100 cm3) by the noncontact method. p-Cymene and γ-terpinene were primarily responsible for the contact toxicity and 1,8-cineole was responsible for fumigation.
From the investigation of termiticidal mechanism, E. camaldulensis leaf oils exhibited the inhibition of acetylcholinesterase activity and showed the common symptoms of a neurotoxic mode of
action against C. formosanus.
Part of this report was presented at the 58th Annual Meeting of the Japan Wood Research Society, Tsukuba, March 2008 相似文献
20.
Michal Hejcman Lukáš Strnad Pavla Hejcmanová Vilém Pavlů 《Journal of pest science》2012,85(2):191-198
Several authors record high mortality of the weedy species Rumex obtusifolius in unmanaged grasslands, but there have never been any studies on how the performance and mortality of R. obtusifolius and R. crispus are affected by different nutrient availability in unmanaged temperate grasslands. To investigate this question, we established
a seedlings transplantation and fertiliser experiment on unmanaged Dactylis glomerata grassland in Czech Republic. We monitored plant height, number of leaves per plant, fertility and mortality of transplanted
R. obtusifolius and R. crispus plants, from 2008 to 2011, in an unfertilised (U) and a fertilised (F) treatment (manure applied in 2008 at the rate of 200 kg
of nitrogen, 42 kg of phosphorus and 230 kg of potassium per ha). In 2010, taller plants of both species were recorded in
treatment F than in treatment U, but there was no effect of treatment on the number of leaves. In 2010, fertility for both
species was 50% in treatment F, but only 20% for R. obtusifolius and 10% for R. crispus in treatment U. Over 4 years, no mortality of R. obtusifolius in treatment F contrasted with 30% mortality in treatment U. In the case of R. crispus, mortality was 50% in treatment F and 28% in treatment U. An increase in nutrient availability can decrease mortality of
R. obtusifolius plants in grasslands, but increase mortality of R. crispus. It seems that leaving grassland unmanaged for several years is only an effective strategy for control of R. obtusifolius under conditions of low nutrient availability. 相似文献
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