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为探明有机肥对沙地樟子松生长的影响,在沙地樟子松幼龄林、中龄林连续4年进行带状沟施有机肥(生物炭、猪粪和牛粪),测量单株树高、胸径和材积。结果表明:不同配比的有机肥可以促进沙地樟子松幼龄林和中龄林树高、胸径和单株材积生长,幼龄林最佳施肥量为生物炭66.67 kg·hm-2、猪粪66.67 kg·hm-2、牛粪17.80 kg·hm-2,中龄林最佳施肥量为生物炭53.33 kg·hm-2、猪粪200.00 kg·hm-2、牛粪200.00 kg·hm-2。因此合理施肥能促进沙地樟子松幼龄林、中龄林的生长。 相似文献
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宋立志 《内蒙古林业调查设计》2018,(1):88-90
文章以不同修枝处理的中辽1号杨人工林为研究对象,采用的是以不修为对照,半修、全修的处理重度的修枝方式进行试验研究;分析了不同修枝处理对生长量、材积的影响,试验结果显示:经过4 a的对比试验,全修的树高平均增长量提高了50.0%,胸径平均增长量提高了17.5%,单株材积平均增长量提高了48.7%,与对照相比差异显著。 相似文献
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为了研究N、P、K含量对马尾松新造林生长量的影响。通过对土壤养分进行分析,设置4个N、P、K不同含量配比的配方肥,连续3年对马尾松幼林进行了配方施肥处理,连续4年对马尾松幼林生长情况进行了跟踪观察测定。结果表明:4个配方肥马尾松胸径年平均生长量分别为2.6 cm、2.75 cm、2.625 cm、2.6 cm,比CK年平均胸径2.375 cm高出9.47%~15.79%,各处理对胸径生长的影响依次为处理2>处理3>处理>1处理4;马尾松树高年平均生长量分别为1.575 m、1.55 m、1.55 m、1.525 m,比CK树高年均生长量1.475 m分别高出3.39%~6.78%,对马尾松树高的影响依次为处理1>处理4>处理>2处理3;4年生马尾松平均年蓄积量为1.604 m3、1.757 m3、1.610 m3、1.559 m3比CK年平均蓄积量1.227 m3高出22.04%~25.61%,对马尾松单株材积的影响依次为处理2>处理3... 相似文献
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刨花楠生长规律的初步研究 总被引:5,自引:0,他引:5
刨花楠胸径前期生长较慢,10 ̄15年生为生长高峰期;树高生长前期较快,25年生后生长较慢,10年生前为生长高峰期;材积生长15年生前较慢,以后上升较快,45 ̄50年生为生长高峰期。该树种速生期较长,是培育大径级用材较理想的树种。 相似文献
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通过对虎皮楠、光皮烨、火力楠三种7年生阔叶树在20米宽林带中生长效果的调查分析,结果表明三种树种在树高、胸径、每公顷蓄积三个方面,虎皮楠与火力楠间无显著差异,而光皮桦与虎皮楠、火力楠的差异均显著. 相似文献
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林业科普队伍建设是林业职工科学素质建设的基础工作。林业科普队伍建设的重点是抓好乡村林业科普队伍建设、林业企业科普队伍建设、社区林业科普队伍建设、林业科普志愿者队伍建设等。本文还对加强林业科普队伍建设的保障措施进行了探讨。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):106-114
Decomposition of organic matter in forest soils controls mineralization of nutrients. The decomposition is to a large extent controlled by climatic and soil conditions. Four different soil treatments of water and nutrients were applied to a Norway spruce (Picea abies) stand in Denmark, and the relative changes in decomposition rate were quantified by the cotton strip assay. Additions of water and nutrients to the soil increased the decomposition of the cotton strips significantly, especially in the deeper soil layers. Reduced water addition during the summer, thereby creating ‘summer drought’, caused no changes in the decomposition compared to an untreated control situation, but the spatial variability in the decomposition within the treatment plot was strongly increased. The decomposition of the cotton strips decreased linearly with the soil depth (1st order). 相似文献
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A. Fedorkov 《Forest Pathology》2007,37(2):136-142
A field experiment with artificial soil contamination by the heavy metals copper and nickel was established in Kola Peninsula, northern Russia. To study the effect of soil contamination by heavy metals without SO2 air pollution on the Scots pine trees growth the experiment was located outside the range of forest damage due to emissions from a copper–nickel smelter. Retardation in tree diameter growth over 15 years after contamination with 20 kg of metallurgical dust per 100 m2 plot was 54%, 10 kg 27%, 5 kg 16% and 2.5 kg 7%, respectively, compared with growth in control plots. Thus, decreasing Scots pine growth due to heavy metal pollution was demonstrated. 相似文献
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? Context
Models for predictions of soil compaction following forest traffic represent important decision tools for forest managers in order to choose the best management practices for preserving soil physical quality. In agricultural soil compaction research, analytical models are widely used for this purpose.? Aims
Our objective was to assess the ability of an analytical model to predict forest soil compaction under forwarder traffic.? Methods
We used the results from two experimental sites set up in north-eastern France in 2007 and 2008 to compare simulations using the SoilFlex model with observed bulk density following forwarder traffic.? Results
The best model-based predictions were found when considering the mean initial soil conditions and an increased rebound parameter in the upper soil layers (0–10 cm) in comparison to the deeper layers (10–50 cm). The need to increase the rebound parameter in the soil surface layer to improve model accuracy was attributed to a large soil organic matter content in the uppermost layers of forest soils. For the site where initial soil mechanical parameters were measured as a function of soil bulk density and water content, the model performance was good, with a root mean square error (RMSE) of 0.06. The model performed poorer (RMSE of 0.11), especially for the surface soil layer, for the second site that was wetter at the time of traffic and where soil mechanical properties were not measured but estimated by means of pedo-transfer functions.? Conclusions
SoilFlex was found to yield satisfactory predictions and could help forest managers estimate the risk of compaction and to select the most appropriate machinery for given soil conditions in order to preserve the soil from physical degradation during traffic in forest ecosystems. However, our results emphasise the need for research on soil mechanical properties of forest soils, in particular on the role of soil organic matter and roots on soil compressive properties. 相似文献15.
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Fungi isolated from the oak (Quercus robur) rhizosphere were tested for their effects on rhizomorph formation and growth of 16 isolates of Armillaria ostoyae sampled in three localities in western Poland. The number of rhizomorphs, number of rhizomorph apices, and rhizomorph length and weight increased most in the presence of Penicillium lanosum, Penicillium notatum, Cylindrocarpon destructans, Penicillium spinulosum and Mycelium radicis atrovirens α and, to a lesser extent, in the presence of Nectria grammicospora. Inhibition of rhizomorph formation was caused by Trichoderma hamatum and Trichoderma viride in two A. ostoyae isolates and by M. radicis atrovirens α and P. spinulosum in one A. ostoyae isolate. It is suggested that variation in sensitivity to microbial stimulation within A. ostoyae is associated with the environmental and nutritional conditions of its original habitat. Isolates from nutrition‐rich localities, with 20% of the land area covered by deciduous trees, were particularly susceptible to stimulation by rhizosphere fungi. 相似文献
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Hultine KR Koepke DF Pockman WT Fravolini A Sperry JS Williams DG 《Tree physiology》2006,26(3):313-323
We investigated hydraulic constraints on water uptake by velvet mesquite (Prosopis velutina Woot.) at a site with sandy-loam soil and at a site with loamy-clay soil in southeastern Arizona, USA. We predicted that trees on sandy-loam soil have less negative xylem and soil water potentials during drought and a lower resistance to xylem cavitation, and reach E(crit) (the maximum steady-state transpiration rate without hydraulic failure) at higher soil water potentials than trees on loamy-clay soil. However, minimum predawn leaf xylem water potentials measured during the height of summer drought were significantly lower at the sandy-loam site (-3.5 +/- 0.1 MPa; all errors are 95% confidence limits) than at the loamy-clay site (-2.9 +/- 0.1 MPa). Minimum midday xylem water potentials also were lower at the sandy-loam site (-4.5 +/- 0.1 MPa) than at the loamy-clay site (-4.0 +/- 0.1 MPa). Despite the differences in leaf water potentials, there were no significant differences in either root or stem xylem embolism, mean cavitation pressure or Psi(95) (xylem water potential causing 95% cavitation) between trees at the two sites. A soil-plant hydraulic model parameterized with the field data predicted that E(crit) approaches zero at a substantially higher bulk soil water potential (Psi(s)) on sandy-loam soil than on loamy-clay soil, because of limiting rhizosphere conductance. The model predicted that transpiration at the sandy-loam site is limited by E(crit) and is tightly coupled to Psi(s) over much of the growing season, suggesting that seasonal transpiration fluxes at the sandy-loam site are strongly linked to intra-annual precipitation pulses. Conversely, the model predicted that trees on loamy-clay soil operate below E(crit) throughout the growing season, suggesting that fluxes on fine-textured soils are closely coupled to inter-annual changes in precipitation. Information on the combined importance of xylem and rhizosphere constraints to leaf water supply across soil texture gradients provides insight into processes controlling plant water balance and larger scale hydrologic processes. 相似文献
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