共查询到20条相似文献，搜索用时 26 毫秒
1.
Sun Hong-gang Zhang Jian-guo Duan Ai-guo He Cai-yun 《中国林学(英文版)》2007,9(1):85-94
Growth and yield modeling has a long history in forestry. The methods of measuring the growth of stand basal area have evolved from those developed in the U.S.A. and Germany during the last century. Stand basal area modeling has progressed rapidly since the first widely used model was published by the U.S. Forest Service. Over the years, a variety of models have been developed for predicting the growth and yield of uneven/even-aged stands using stand-level approaches. The modeling methodology has not only moved from an empirical approach to a more ecological process-based approach but also accommodated a variety of techniques such as: 1) simultaneous equation methods, 2) difference models, 3) artificial neural network techniques, 4) linear/nonlinear regres-sion models, and 5) matrix models. Empirical models using statistical methods were developed to reproduce accurately and precisely field observations. In contrast, process models have a shorter history, developed originally as research and education tools with the aim of increasing the understanding of cause and effect relationships. Empirical and process models can be married into hybrid mod-els in which the shortcomings of both component approaches can, to some extent, be overcome. Algebraic difference forms of stand basal area models which consist of stand age, stand density and site quality can fully describe stand growth dynamics. This paper reviews the current literature regarding stand basal area models, discusses the basic types of models and their merits and outlines recent progress in modeling growth and dynamics of stand basal area. Future trends involving algebraic difference forms, good fitting variables and model types into stand basal area modeling strategies are discussed. 相似文献
2.
Application of Grey System Theory to tree growth prediction 总被引：1，自引：0，他引：1
IntroductionDahurian larch plantations were planted affer the1950's in Heilongjiang Province. Some of them areless than 40 years old. There lack permanent plots oflong-term. Sometimes, statistical models for predicting tree growth are not always desirable. The GreySystem is a new branch of mathematics founded byProf. Deng Julong in 1982 (Deng 1985). In contrast tostatistic models, which need a lot of measured data,the Grey System only need a f6w data for setting upmodels. In recent years… 相似文献
3.
Root secretion stimulating ash growth in larch-ash mixed forest 总被引：1，自引：0，他引：1
IntroduchonRePOrt6d as early as 1920s, the groWth of ashcould be increaSed as ash was mixed with larch.However, the mechanism of allelopathic effect betwedn larch and ash has not been clearly yet. Theallelopathic ~ in mixed forest were generallyregard6d as fOllowing four wayst volatile matt6rs, rootsecredon, St6m leaching, and litter decompositionmatt6rs (Zhai 1993). This paper presented the studies on the ~ of root secretion, focused on thosestimulahon allelochemicals that can increase the… 相似文献
4.
Markku Ollikainen 《Scandinavian Journal of Forest Research》2014,29(4):360-366
This paper draws on the European Union's Bioeconomy Action Plan (BAP) to clarify the notion “bioeconomy” and examine how it relates to the forest sector and its current challenges. The interpretation is linked to a broader context of climate and energy policies and the ideas of green economy and green growth. It is shown that, despite its good intentions, BAP fails to link bioeconomy to the core idea of green economy and the sources of economic growth. It hardly discusses climate policies and entirely omits the land-use aspects between agriculture and forestry that are important for climate policies. An equally serious shortcoming is that BAP very vaguely recognizes the role and nature of the forest sector as a high-tech biomass utilizing sector and omits its current challenge to renew the product matrix from forest biomass as a response to the decreasing demand for paper. An overview of the topical issues in forest sector shows that it has and will have a great role in bioeconomy as a high-tech and high value-added sector producing all traditional products, bioenergy, and new forest products. 相似文献
5.
Mu Jun Yu Zhi-ming Wu Wen-qiang Wu Qing-li 《中国林学(英文版)》2006,8(3):43-47
1 Introduction Bamboo vinegar is a condensed acidic liquid obtained in the process of producing bamboo charcoal. It has a special smoky odor and its color is light-yellow to brown. There are over 200 kinds of chemical compo- nents involved and these components mainly include organic acids, phenolic, alkone, alcohol and ester compounds. Of these, acetic acids are the main com- ponents, accounting for about 50% of the organic chemicals. Bamboo vinegar has been found to have an effect on improvi… 相似文献
6.
lntroductionConcerningthemechanismoftheinteractionbe-tWeentreespeciesinthelarch(LafisgmelinI)-ash(PraxiPusmandShuFbe)mixedforest,wehavestudiedtheaIIelopathiceff6ctsoftheIarchvolatilematter,litterandrootsecretion.onthegroWthofash.TheobtainedresultsshowedclearIythatthelarchvoIatiIematt6rplayedaninhibitivepart,andboththeIarchIitt6randrootsecretionpIayedanobviousfystimuIatingpaFtontheashgroWth(Wu2oooa,2ooob,2oooc).Thispapermakesastudyofanotherallelo-pathicway(Ieaching)betWeenlarchandash.T… 相似文献
7.
8.
Larch is one of the most important plantation species in the northeast region of China. After clear cutting of larch plantations it is the urgent problem to besolved that whether the second generation is continuously plant6d, whether the soil fertility is decreasing and the plantstion is how to be managed onthe forestry produCtion. In odder tO realize the secondgenerahon Of larch plantstions and to provide thetheoretical base and the reasonable managementmeasures, we inventoried the groWth o… 相似文献
9.
IntroductionAsagrowthmodelforanindividualtreeorforeststhnd,theChapman-RichardsFunction,anextensiontotheVonBertalanffy'sgrowththeory(Bertalanffy1957)embodiesallotherestablishedgrowthfunction.ThisfunctionhasbeenwideIyusedinforestrybecauseofitsflexibility,ac… 相似文献
10.
TANGWei LatoyaHarris RonaldJ.Newton 《林业研究》2004,15(3):227-232
The cell cycle is an important research field in cell biology and it is genetically and developmentally regulated in animals and plants. The aim of this study was to review knowledge about the biochemical regulation of the cell cycle by plant growth regulators through molecular checkpoints that regulate the transition from G0-G1-S-phase and G2-M in higher plants.Recent research has shown that zeatin treatment led to the up-regulation of CycD3 in Arabidopsis. Benzyladenine treatment can also shorten the duration of S-phase through recruitment of latent origins of DNA replication. Kinetin is involved in the phosphoregulation of the G2-M checkpoint; the major cyclin-dependent kinase (Cdk) at this checkpoint has recently shown to be dephosphorylated as a result of cytokinin treatment, an effect that can also be mimicked by the fission yeast Cdc25 phosphatase. Gibberellic acid (GA) treatment induces internode elongation in deepwater rice, this response is mediated by a GA-induced up-regulation of a cyclin-Cdk at the G2-M checkpoint. Recent evidence has also linked abscisic acid to a cyclin-dependent kinase inhibitor. A new D-type cyclin, recently discovered in Arabidopsis may have a key role in this process. A brief review on plant growth regulator-cell cycle interfacing during development and a cytokinin-induced continuum of cell cycle activation through the up-regulation of a plant D-type cyclin at the G1 checkpoint and the phosphoregulation of the Cdk at the G2/M checkpoint had been concluded. This review could be valuable to research on cell and developmental biology in plants. 相似文献
11.
《Scandinavian Journal of Forest Research》2012,27(1-4):237-247
Leader shoot damage was imposed on young Scots pines (3 m high) in four ways: by caging the uppermost whorl including the leader shoot with 10 pine shoot beetles; by caging the two uppermost whorls with 20 beetles; by topping the tree below the 1984 whorl; by topping the trees as above and removing all current shoots in whorl 1983. Six years later, top‐damaged trees were still significantly shorter than undamaged controls, although the annual height growth rate had recovered to the pre‐damage level within 3 years. Recovery occurred in two ways: lateral branches from the nearest intact whorl took dominance over the damaged leader or secondary branches developed from interfascicular buds on the damaged leader shoot. Approximately one and two years of height growth were lost in the former and latter case, respectively. Only 5 of the 34 top‐damaged trees escaped technical defects (crooks and/or vertical branches). Stem diameter and crown development were slightly affected. 相似文献
12.
Eight provenances of 19-year-oldPicea koraiensis Nakai from the provenance trials of Maoershan (45°20′N, 127°30′E), Liangshui (47°10′N, 128°53′E) and Jiagedaqi (50°24′N,
124°07′E) in Northeast China were investigated to analyze the genetic variation in growth characteristics (tree height and
diameter) and wood characteristics (tracheid length, tracheid diameter, tracheid wall thickness, annual ring width as well
as wood density). Great variation in height growth and breast height diameter growth was observed among the provenances, and
along with the increase of tree age, these provenances presented different geographic adaptability. The growth characteristics
ofPicea koraiensis stand at age of 10 in Maoershan and Liangshui provenance trials had a positive correlation with longitude, and with increase
of tree age to 15 and 19, the tree growth of the provenances displayed a significant positive correlation with latitude as
well as altitude. For wood characteristics, great variation was also found among the provenances. There exists a close relation
between growth characteristics and wood properties of the provenance. The height and breast height diameter growth of the
provenance had a positive correlation with tracheid diameter and annual ring width, and a negative correlation with tracheid
wall thickness and wood density. Genetic performance of the provenance in all above characteristics was also investigated
in order to provide more useful information for comprehensive selection of this species for pulpwood and plywood production.
Foundation item: The paper was supported by National Key Project of The State Forestry Administration. (96-011-01-06)
Biography: WANG Qiu-yu (1957-), female, professor in College of Life Sciences, Northeast Forestry University, Harbin 150040, P. R.
China.
Responsible editor: Song Funan 相似文献
13.
Adzo Dzifa Kokutse Alexia Stokes Nomessi Kuma Kokutse Kouami Kokou 《Annals of Forest Science》2010,67(4):407-407
14.
《Scandinavian Journal of Forest Research》2012,27(1-4):55-66
In full‐sib families of Picea abies (L.) Karst. (Norway spruce) the dynamics of juvenile growth and the inheritance of the most important growth characters were analysed in six growth periods in climate chambers followed by two additional growing seasons in a nursery. The full‐sib families were of French and North Swedish origin including both within and between provenance crosses. All growth rhythm characters changed over time. For instance, number of days to budbreak increased, whereas days to budset decreased, as growth periods advanced. Concurrent with the changes in growth rhythm, free growth decreased with increasing age. Half of the total variation for different growth rhythm characters within a growth period could in most cases be explained by provenance effects. Early selection is, therefore, meaningful to reduce damage by frost and mortality. Furthermore, the actual distances between family means decreased substantially with increasing age, and the actual length of the shoot elongation period decreased from 31 days during the second growth period to 16 days during the sixth. We suggest therefore that selection together with some treatment in the nursery that alters the growth rhythm of the seedlings are the best ways to increase frost resistance. Tree height was influenced by a set of complex gene actions that changed over time. Provenance effects were important during the first two growth periods. Subsequently, non‐accumulative within provenance family variance took over. If this pattern holds true in general, juvenile selection for height growth in Norway spruce cannot be made as early as that for growth rhythm. 相似文献
15.
Simon Egli François Ayer Martina Peter Britta Eilmann Andreas Rigling 《Annals of Forest Science》2010,67(5):509-509
16.
• Introduction
Deterministic single-tree models are commonly used in forestry. However, there is evidence that stochastic events may interact with the nonlinear mechanisms that underlie forest growth. As a consequence, stochastic and deterministic simulations could yield different results for the same single-tree model and the same initial conditions. This hypothesis was tested in this study. 相似文献17.
Once forests have achieved a full canopy, their growth rate declines progressively with age. This work used a global data set with estimates from a wide range of forest types, aged 20-795 years, of their annual photosynthetic production(gross primary production, GPP) and subsequent above-plus below-ground biomass production(net primary production, NPP). Both GPP and NPP increased with increasing mean annual temperature and precipitation. GPP was then unrelated to forest age whilst NPP declined progressively with increasing age. These results implied that autotrophic respiration increases with age. It has been proposed that GPP should decline in response to increasing water stress in leaves as water is raised to greater heights as trees grow taller with age. However, trees may make substantial plastic adjustment in mor phology and anatomy of newly developing leaves, xylem and fi ne roots to compensate for this stress and maintain GPP with age. This work reviews the possibilities that NPP declines with age as respiratory costsincrease progressively in, any or all of, the construction and maintenance of more complex tissues, the maintenance of increasing amounts of live tissue within the sapwood of stems and coarse roots, the conversion of sapwood to hear twood, the increasing distance of phloem transport, increased turnover rates of fine roots, cost of supporting very tall trees that are unable to compensate fully for increased water stress in their canopies or maintaining alive competitively unsuccessful small trees. 相似文献
18.
C. acuminata seedlings cultivated in greenhouse were transplanted into the fields with 5 designed planting densities (11, 16, 25, 44 and
100 plants·m−2) in May of 2004 and were harvested in the middle of September of 2004. The seedling growth indexes including plant height
and crown width, biomass allocation, camptothecin (CPT) content and CPT yield of different organs (young leaf, old leaf, stem,
and root) were studied. For the 5 selected planting densities, the plant biomass, height, crown width, and total leaf area
ofC. acuminata seedlings all showed highest values at the planting density of 25 plants·m−2. CPT content in young leaves was higher than that in other organs of seedlings and presented an obvious change with the variation
of planting densities and with the highest value at density of 100 plants·m−2, while for other organs no significant variation in CPT content was found with change of planting density. The accumulation
of CPT was enhanced significantly at the planting density of 25 plants·m−2. It is concluded that for the purpose to get raw materials with more CPT fromC. acuminata, the optimal planting density ofC. acuminata seedlings should be designed as 25 plants·m−2.
Foundation item: This paper was supported by the National Natural Science Foundation of China (No. 3970086) and Heilongjiang Province Foundation
for Distinguished Youth Scholars (JC-02-11)
Biography: Wei Huan-yong (1978-), male, Graduate in College of Life Sciences, Northeast Forestry University, Harbin 150040, P. R. China.
Responsible editor: Zhu Hong 相似文献
19.
IntroductionGIobaIchangehasbeenoneoftheimpoFtantis-suesandscientistspaycIoseattentiontoit.ThegreatimportanceofforestecosystemisreflectednotonlybytheirhUgebiomass,butaIsobytheirsignifi-cantroIeintheglobaIcarbonbaIance.Howtreesrespondtoclimaticchangesmightbeofgreatsig-nificance.ManystudiesindicatethattherisingatmosphericCo,leveIscanmakeasubstantialeffectonplantgroWthanddevelopment.SomeonethinkcommonlythattherisingCo,levelscanstimuIatepIantgroWthandbiomassproduction,sincephotosynthesisofC… 相似文献
20.
Does tree seedling growth and survival require weeding of Himalayan balsam (Impatiens glandulifera)?
Christian Ammer Peter Schall Ren�� W?rdehoff Klaus Lamatsch Martin Bachmann 《European Journal of Forest Research》2011,130(1):107-116
The effect of Himalayan balsam (Impatiens glandulifera) on survival and growth of naturally regenerated silver birch (Betula pendula) and planted Norway spruce (Picea abies) and silver fir (Abies alba) seedlings was studied in a weeding experiment over 3 years. Three different treatments were applied: control, mowing, and hand weeding by pulling out the entire plant. There were no consistent treatment effects on height and diameter of the tree seedlings. The coverage of Rubus fruticosus had a negative impact on diameter increment of Norway spruce and silver fir. As opposed to growth, treatment effects on seedling survival could be found for planted Norway spruce and silver fir. However, it is very likely that these effects, namely higher seedling survival after mowing, have to be attributed to the control of bramble (Rubus fruticosus) rather than to that of Himalayan balsam. It is concluded that Himalayan balsam is not able to seriously affect the growth of already established seedlings. 相似文献