共查询到19条相似文献,搜索用时 250 毫秒
1.
2.
3.
刘爱琴 《中南林业科技大学学报(自然科学版)》1999,(3)
采用完全随机区组设计,分别对杉木造林前穴底、幼林及中龄林施城市固体垃圾肥,以研究该肥对杉木生长的影响.结果表明,杉木造林前穴底施垃圾肥肥效显著,以每穴施 37.5 kg 肥效最好,第2 年地径、树高生长量分别比对照增加27.68% 和25.41% ;幼林施垃圾肥对杉木生长有一定促进作用,当年肥效不明显,其中 37.5k g/株垃圾肥处理在第 3 年胸径、树高生长量分别比对照增加21. 29% 和 24.14% ,不同施肥处理第 3 年对杉木生长效应排序为:垃圾肥 37.5 kg/株(记为 L37.5)> L25> L12.5> N0.25(尿素0.25 kg/株);杉木中龄林施垃圾肥具有明显增产效应,随时间推移,各施肥处理对杉木生长效应排序为:L37.5> L25> N0.25> L12.5.,且肥效渐趋明显 相似文献
4.
杉木人工林迹地更新树种选择研究 总被引:3,自引:0,他引:3
在杉木人工林皆伐迹地上,对4个速生优质用材料树种(种源)进行了栽培试验。经过14年的试验研究表明:连栽杉木造林成活率、保存率较低,生长不如长一代林,更新困难;而使用秃杉(Taiwania flousiana云南种源)、柳杉(Cryptomeria fortunei浙江天目山种源)造林适应性强、生长快、产量高,14年生单株立木材积分别比杉木提高178.0%和327.6%,这是杉木人工林皆伐迹地较理想 相似文献
5.
本文用在遂昌调查的标准地资料,建立杉木人工林平均胸径、林分平均高、每公顷断面积和林分蓄积量生长方程,以此编制杉木人工林现实收获表,并简单分析遂昌县杉木人工林的生长特点,预估了杉木人工林的年生长量。杉木是遂昌县最重要的用树树种之一,从70年代初大规模人工造林以来,已营造杉木人工林56278hm2,蓄积量1029876m3,如何提高杉木人工林的经营效益,提高林业的经济效益是目前亟需解决的问题。为此本文试图通过对现有杉木人工林的调查,编制现实收获表,为生长预估、森林经营提供理论依据。 相似文献
6.
多代杉木人工林生长发育效应的研究 总被引:18,自引:2,他引:16
在全国杉木中心产区,选择不同栽植代数(1、2、3代)、不同发育阶段(5、10、15、20年)、不同立地(14、16、18地位指数)的杉木人工林,进行不同栽植代数杉木人工林生长发育特点的比较研究,结果表明:连栽导致了杉木生长的明显衰退,2、3代杉木戏分别比1代杉木下降7.29% ̄11.61%和15.63% ̄21.47%,树高分别下降7.89% ̄11.76%和17.76% ̄22.35%,蓄积量分别下降21.02% ̄24.61%和38.70% ̄44.18%,而且随栽植代数的增加,杉木戏、树高生长速生期开始时间推迟,速生期缩短,林木分化日趋明显,中级木比例减少,大、小级木比例增加。 相似文献
7.
福建永安市杉木人工林产量及密度现状的研究 总被引:1,自引:1,他引:0
收集永安市杉木人工林基准年龄(20年)林分数据,应用气候生产潜力、密度效应指标等原理,对永安市杉木人工林产量及密度现状研究分析,提出符合永安市杉木人工林生长规律的培育措施,为杉木人工林培育获取较大经济效益提供理论参考。 相似文献
8.
施本俊 《中南林业调查规划》1995,(1)
以杉木人工林营林生产作业项目工程量(人工、材料、机械、运输)和林分生长过程表资料,分别未成熟林阶段和可售林木阶段,用平均现实成本和价格确定资产估价是一种科学实用的方法. 相似文献
9.
应用林分解析法编制货币收获表 总被引:1,自引:0,他引:1
以闽北33年生杉木人工林标准地分径阶选取的解析木为对象,拟合了杉木人工林的生长模型,测算了林分出材量。依据目前杉木人工林木材生产经营的有关技术经济指标,编制了杉木人工林货币收获表,并在此基础上,探讨货币收获表在确定杉木经济成熟上的具体应用。 相似文献
10.
施本俊 《中南林业调查规划》1995,14(1):25-29
以杉木人工林营林生产作业项目工程量(人工、材料、机械、运输)和林分生长过程表资料,分别未成熟林阶段和可售林木阶段,用平均现实成本和价格确定资产估价是一种科学实用的方法。 相似文献
11.
通过对不同坡位7年生杉木纯林生长的调查与研究,结果显示:坡位对杉木纯林各生长指标均有显著影响;林分的平均胸径、树高、冠幅、枝下高、平均单株材积、单位面积木材蓄积量等生长指标一致表现为下坡位>中坡位>上坡位。坡位间以胸径和树高差异最为显著,下坡位林分平均胸径达到10.59 cm,高出中坡位的11.6%,高出上坡位的20.0%;下坡位林分平均树高为7.25 m,高出中坡位的16.7%,高出上坡位的25.4%。下坡位林分的单位面积木材蓄积量要远远高于中坡位和上坡位的,下坡位林分的单位面积木材蓄积量分别高出上坡位的75.1%,中坡位的44.8%。 相似文献
12.
亚热带地区杉木人工林和阔叶林土壤活性有机质研究(英文) 总被引:1,自引:2,他引:1
土壤活性有机质对土壤养分如氮、磷、硫的生物化学循环具有作用,其含量和质量影响土壤的初级生产力。本试验在中国科学院会同森林生态实验站通过对第一代、第二代杉木纯林和地带性阔叶林土壤活性有机质组分的对比研究,发现杉木纯林土壤活性有机质的含量低于地带性阔叶林。第一代杉木纯林易氧化有机碳、微生物生物量碳、水溶性有机碳和水溶性碳水化合物的含量分别比第二代杉木纯林高35.9%、13.7%、87.8%和50.9%,比地带性阔叶林的低15.8%、47.3%、38.1%和30.2%。在调查的三种林地内,土壤微生物生物量碳和水溶性有机碳含量下降幅度较大,其次为水溶性碳水化合物,而易氧化有机碳的变化最小。同时,杉木纯林土壤养分等理化性质也比地带性阔叶林低。这表明在杉木纯林取代地带性阔叶林以及杉木纯林连栽后林地的土壤肥力降低。图3 表2参26。 相似文献
13.
C and N stocks under three plantation forest ecosystems of Chinese fir, Michelia macclurei and their mixture 总被引:1,自引:0,他引:1
Chinese fir (Cunninghamia lanceolata), a type of subtropical fast-growing conifer tree, is widely distributed in South China. Its plantation area covers more
than 7 × 106 hm2, accounting for 24% of the total area of plantation forests in the country. In recent decades, the system of successive plantation
of Chinese fir has been widely used in southern China due to anticipated high economic return. However, recent studies have
documented that the practice of this system has led to dramatic decreases in soil fertility and forest environment as well
as in productivity.
Some forest ecologists and managers recognize the ecological role performed by broadleaf trees growing in mixtures with conifers,
and a great deal of studies on mixture effects have been conducted, particularly on mixture species of temperate and boreal
forests, but these research results were not completely consistent. Possibilities include dependence of the mixture effects
in large part to specific site conditions, the interactions among species in mixtures and biological characteristics of species.
Although some researchers also studied the effects of mixtures of Chinese fir and broadleaf tree species on soil fertility,
forest environment and tree growth status, little information is available about the effects of Chinese fir and its mixtures
with broadleaves on carbon and nitrogen stocks.
The experimental site is situated at the Huitong Experimental Station of Forest Ecology, Chinese Academy of Sciences, Hunan
Province (26°40′–27°09′ N, 109°26′–110°08′ E). It is located at the transition zone from the Yunnan-Guizhou Plateau to the
low mountains and hills of the southern bank of the Yangtze River at an altitude of 300–1,100 m above mean sea level. At the
same time, the site is also a member of the Chinese Ecosystem Research Network (CERN), sponsored by the Chinese Academy of
Sciences (CAS). This region has a humid mid-subtropical monsoon climate with a mean annual precipitation of 1,200–1,400 mm,
most of the rain falling between April and August, and a mean temperature of 16.5°C with a mean minimum of 4.9°C in January
and a mean maximum of 26.6°C in July. The experimental field has red-yellow soil.
After a clear-cutting of the first generation Chinese fir (Cunninghamia lanceolata) plantation forest in 1982, three different plantation forest ecosystems, viz. mixture of Michelia macclurei and Chinese fir (MCM), pure Michelia macclurei stand (PMS) and pure Chinese fir stand (PCS), were established in the spring of 1983. A comparative study on C and N stocks
under these three plantation forest ecosystems was conducted in 2004. Results showed that carbon stocks were greater under
the mixtures than under the pure Chinese fir forest and the pure broad-leaved forest, and the broadleaves and the mixtures
showed higher values in nitrogen stocks compared with the pure Chinese fir forest. The spatial distribution of carbon and
nitrogen stocks was basically consistent, the value being greater in soil layer, followed by tree layer, roots, understory
and litter layer. The carbon and nitrogen stocks in soil layer were both highly correlated with the biomass in understory
and litter layer, indicating that understory and forest litterfall exerted a profound effect on soil carbon and nitrogen stocks
under plantation ecosystems. However, correlations among soil carbon, nitrogen stocks and below ground biomass of stand have
not been observed in this study.
Translated from Acta Ecologica Sinica, 2005, 25(12): 3,146–3,154 [译自: 生态学报] 相似文献
14.
15.
1984~1996年在江西分宜县中国林科院亚热带林业实验中心的3个林场,分别对杉木人工林幼龄林、中龄林及近熟林进行了8组水土保持及养分循环方面多点的试验观测,对杉木人工林水土流失及养分损耗作了研究。结果表明,杉木人工林水土流失以幼林阶段为最大,其次中龄林阶段,最小是近熟林阶段。幼龄林地表迳流量为546.0m^3.hm^-2,土壤侵蚀总量为1050.0kg.hm^-2,土壤侵蚀量尤为明显;中龄林地表迳流量为506.98m^3.hm^-2;而近熟林地表迳流量为477.25m^3.hm^-2,土壤侵蚀量可略而不计。幼龄林流失有机质50.049kg.hm^-2,养分为31.508kg.hm^-2;中龄林流失有机质为6.080kg.hm^-2,养分流失量为2.096kg.hm^-2,而近熟林养分流失量为10.784kg. 相似文献
16.
17.
In order to decrease the soil nutrient loss in young planted Chinese fir (Cunningharnia lanceolata (Lamb.) Hook.) forestland
and to investigate the impact of young Chinese fir plantation intercropped with crops on soil quality, a field experiment
was set up in the mid-subtropics of China in 1998. The effects of growing crops in combination with young Chinese fir on soil
properties were evaluated by measuring physico-chemical, microbiological and biochemical parameters five years after the beginning
of this experiment. Three treatments were selected in the experiment, i.e., Chinese fir plantation intercropped with peanut
(Arachis hypogaea L.) -wheat (Triticum aestivum L.) cropping sequence (C-P/W); Chinese fir plantation intercropped with maize
(Zea mays L.)-wheat cropping sequence (C-M/W) and only Chinese fir plantation (Control). Soils were sampled at the 0–10 cm
depth in 2003. The increases in soil nutrients (especially with respect to soil available nutrients), soil microbial biomass
C (SMBC), microbial quotient (MQ), soil basal respiration (SBR), microbe numbers and enzyme activities and slight decrease
in metabolic quotient (qCO2) as well as melioration in soil structure and humus quality were observed in tree-crop combinations compared with sole plantation
of Chinese fir, although the differences were not always statistically significant. In addition, the evidence obtained from
this study also suggests that Chinese fir-crop combination can promote the growth of young Chinese fir. Therefore, growing
crops in combination with young Chinese fir can be considered a good forest management practice, helping to limit the gradual
depletion of soil nutrients and, at the same time, to some degree controlling the degradation of planted Chinese fir forestland. 相似文献
18.
闽东高海拔山地地形因子对杉木人工林生长的影响 总被引:1,自引:0,他引:1
应用地形5个因子在2个水平下的正交试验设计方法,系统分析了闽东高海拔山地14年生杉木人工林生长的变化规律,结果表明:影响杉木人工林胸径、树高的各地形因子的重要程度依次为:坡形>坡位>坡向>海拔>坡度,影响杉木人工林冠幅的各地形因子的重要程度依次为:坡形>坡位>坡向>坡度>海拔,影响杉木人工林枝下高的各地形因子的重要程度依次为:坡形>坡位>海拔>坡向>坡度。坡形对杉木人工林胸径、树高和枝下高影响显著,坡位对杉木人工林树高影响显著。影响杉木人工林生长的最重要地形因子是坡形,其次是坡位,坡向、海拔和坡度(在45°以内)对杉木人工林生长影响不显著。 相似文献