首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 171 毫秒
1.
广西派阳山林场马尾松高产高效用材林培育技术研究   总被引:1,自引:0,他引:1  
马尾松是广西派阳山林场主要经营树种,营造了大面积马尾松速生高产林,年平均材积生长量达25.5m^3/hm^2,其中大风坳35hm^225年生,产量达867.45m^2/hm^2(包括间伐材),平均年生长量达34.65m^3/hm^2,经过十余年的调查与定位研究,提出立地选择、良种应用、半年苗栽植、密度控制、合理管护,为马尾松速生丰产主要技术措施,研究营造的示范样板林,产量更高。  相似文献   

2.
光皮桦造林技术初探   总被引:6,自引:0,他引:6  
光皮桦材质优良,削面光滑,韧性强是木材加工、削片及“三板”工业的理想材料。南江县光皮桦在天然混交林中的31年生纯林林分两次疏伐后,1hm^2保留500,平均高为19.1m,平均胸径21.3cm,蓄积165m^3。1984、1985年在关坝等地作人工造林对比试验,经1992年10月调查,在一般经营条件下,幼龄期的树高、胸径、材积生长均超过天然林生长量。  相似文献   

3.
油麦吊云杉,是四川盆地西缘山地主要优质用材造林树种之一,28年生人工林主要林分因子胸径13.4cm、树高12.5m、蓄积285.79m^3/hm^2,其林分胸径、树高和蓄积年平均生长量分别达到0.48cm、0.45cm和10.2m^3/m^2.28年生人工林林分养木层生物量为174.96t/hm^2,平均净生产量达7880.8kg/hm^2,year。这表明该树种人工林具有较高生产 在适生地区大力  相似文献   

4.
巨尾桉山地造林速生丰产技术研究   总被引:1,自引:0,他引:1  
通过地巨尾桉无性系山地造林速生丰产综合技术研究表明:造林必须过好“五关”即:选地关、灭蚁关、整地关、造林关、抚育关。当主伐年龄7a,蓄积量可达305m^3/hm^2。年均生长量43.5m^3/hm^2,增产效益是杉木、马尾松的6倍。  相似文献   

5.
鹅掌楸,桤木幼抚技术   总被引:1,自引:0,他引:1  
对营造的鹅掌楸和桤木人工林进行生长和幼林抚育管理技术的观测记载表明,在较好立地上,两树种前期生长迅速,8年生鹅掌楸平均胸径11.87cm、平均高11.79cm,桤木分别为9.21cm和13.77m;对其幼林除草抚育4~5次,修枝在造林后的2~4年中树木停止生长时进行,间伐时间桤木在5~6年进行,鹅掌楸在6~7年进行。  相似文献   

6.
在水土流失严重的丘陵地,对尾叶按、刚果12号按、雷林1号按、大叶相思和马占相思等树种的短轮伐期能源、用材林培育技术进行了8年研究。结果表明,在贫瘠立地培育短轮伐期能源、用材林,必须采取集约经营措施,即通过细致整地(坡地带垦,平原台地全垦)、适当施肥(按属树种以N肥为主,P、K肥为辅;相思类树种以P肥为主,辅以N、K肥)、合理密植(经营超短轮伐期能源林,宜采用0.5m×1m密度,轮伐期为2~3年;短轮伐期能源、用材林一般用1m×1m~1m×2m的株行距造林,轮伐期为4~5年;经营短轮伐期用材林,采用1.5m×3m株行距效果较好,植后6~7年采收,以及间种等措施,才能获得速生、高产和短轮伐效果。  相似文献   

7.
巨尾桉无性系山地引种造林效果的研究   总被引:12,自引:0,他引:12  
通过对引进巨尾桉无性系与巨桉,尾叶桉进行山地造林试验3年的研究结果表明,巨尾桉无性系不仅能适宜本地区山地栽培,而且,生长快,3年生平均树高12.1m,胸径12.3cm,单株带皮材积0.0728m^3,去皮材积0.0574m^3,比尾叶桉分别增长23.5%,28.1%,92.1%和140.2%,比巨桉分别增长13.1%,19.4%,56.6%和51.5%。它还具有树干通直圆满,树皮较薄,冠径比小,出  相似文献   

8.
将南方型杨树“中潜”3号,分别在湖北西部的中低山区、高寒山区进行育苗和造林试验,育苗密度为4000株/667m^2,造林密度为222株/667m^2,其效果与江汉平原相差无几,在中低山育苗一年的超级苗木高4.8m,径3cm,平均苗4.3m,径3cm,要2年的树高5.3m,径6cm,其生长量远远超过目前山区栽种的63、69、72杨及湿地松、日本落叶松。  相似文献   

9.
引种栽培研究表明,秃杉具有较强的适应性,能够适应我国南方中、低山区的气候和土壤。四川盆地秃杉人工幼林年平均高生长量达1.0m,胸径生长量1~1.3cm;江苏、浙江良好立地,5年生时平均树高、胸径分别3.12m和3.5m。云贵高原、四川盆地为秃杉扩大引种栽培的最适引种区;南方中低山丘陵区显示出速生潜力。秃杉造林采用1~2年生优质壮苗,带状整地,株行距1.5m×1.5m  相似文献   

10.
1965年此进东要赤松种子育苗,1967年春造林。28年的引种实践证明,引种是成功的。东宁赤松在辽西干旱地区表现出较强的适应性、抗逆履;林木12年生开始结实;其胸径、树高、材积生长量明显超过本地油松,27年生平均树高6.0m,平均胸径9.5cm,林木单株材积0.0247m^3;林分质量比油松林有明显提高。  相似文献   

11.
《Southern Forests》2013,75(3-4):147-152
Corymbia hybrids are becoming significant plantation varieties in subtropical and tropical Australian plantation forestry. Although primarily developed for disease resistance and amenability to clonal propagation, they have also proven to have good growth rates and site plasticity. Here we examined the susceptibility of pure Corymbia species and hybrids to pest attack. Three trial sites containing C. citriodora subsp. variegata, C. torelliana, and the hybrids C. torelliana × C. citriodora subsp. variegata, C. torelliana × C. citriodora subsp. citriodora and C. torelliana × C. henryi were assessed for pest identity, incidence and severity. Pests caused about three-quarters of the visible crown damage to trees in these trials. At the site that had the most arthropod damage, hybrid trees had higher damage scores and higher growth scores (height, diameter at breast height over bark, and volume) than pure species. Site was more important than taxon in explaining damage scores, and taxa performed differently for most traits between sites. Tree growth was negatively correlated with general crown damage, while arthropod damage alone showed no significant relationship with growth. Our results highlight the importance of establishing taxa trials across a range of sites when selecting for pest resistance.  相似文献   

12.
Forest ecosystems play a significant role in sequestering carbon (C) in biomass and soils. Plantations established in subtropical China since the 1980s, mainly of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) in monocultures, have proved to be major C sinks. However, information is lacking about whether mixing Chinese fir with broadleaved tree species will increase stand growth and C sequestration. We address this question by comparing a pure Chinese fir plantation and two mixed plantations established in 1990 at Huitong Experimental Station of Forest Ecology, Hunan Province, China. The mixed plantations include Chinese fir and either Kalopanax septemlobus (Thunb.) Koidz or Alnus cremastogyne Burk., planted at 4:1 ratios. We found that total C storage was 123, 131 and 142 Mg ha−1 in the pure plantation, mixed plantation with K. septemlobus, and mixed plantation with A. cremastogyne, respectively. The mixed plantation with A. cremastogyne increased C storage in biomass relative to the pure Chinese fir plantation (P < 0.05). No significant difference was detected between mixed plantations. Soil C storage did not differ among these plantations, ranging from 67.9 ± 7.1 to 73.3 ± 9.1 Mg ha−1, which accounted for about 55% of the total C pools. Our results indicated that as the mixture of Chinese fir and broadleaved species will increase both biomass C and soil C storage over pure Chinese fir, and will do it, within 15 years of planting.  相似文献   

13.
Estimation of shrub biomass can provide more accurate estimates of forest biomass and carbon sequestration. We developed species-specific biomass regression models for four common shrub species, Chinese loropetal (Loropetalum chinense), white oak (Quercus fabri), chastetree (Vitex negundo var. cannabifolia), and Gardenia (Gardenia jasminoides), in southeast China. The objective of this study was to derive appropriate regression equations for estimation of shrub biomass. The results showed that the power model and the quadratic model are the most appropriate forms of equation. CA (canopy area, m2) as the sole independent variable was a good predictor of leaf biomass. D 2 H, where D is the basal diameter (cm) and H is the shrub height (cm), is a good predictor of branch and root biomass, except for V. negundo var. cannabifolia and the root biomass of L. chinense. For total biomass, D 2 is the best variable for estimation of L. chinense and G. jasminoides, and D 2 H is the best variable for estimation of Q. fabri and V. negundo var. cannabifolia. Although variables D 2, D 2 H, and H are the preferred predictors for biomass estimation, CV (canopy projected volume, m3) could be used alone to predict branch, root, and total biomass in shrub species with acceptable accuracy and precision.  相似文献   

14.
Pedraza  R.A.  Williams-Linera  G. 《New Forests》2003,26(1):83-99
Four native tree species (Liquidambar styraciflua, Juglans pyriformis, Podocarpus matudae, and Carpinus caroliniana) were evaluated for their suitability in rehabilitating degraded areas of Mexican cloud forest. Plant survival and growth in height and diameter were determined in three mixed-experimental plantations with different land use histories; their performance was compared with two on-farm plantations started by landowners for forest restoration. Nearby forest fragments were controls for soil compaction. An experimental plantation with remnant trees had the highest plant survival (82%), height, basal diameter and relative growth rate. The plantation with the steepest slope had high plant survival (63%) and growth. The plantation characterized by dominance of grasses and compacted soils had the lowest survival (22%) and growth. On-farm plantations had good establishment of planted trees (5–10 species planted), and facilitated the recruitment of 9–11 woody species. Carpinus and Liquidambar appear to be suitable species for reforestation in all these areas. Podocarpus grew relatively slowly, although it performed well in two experimental sites. Juglans had high survival (76%) under the stressful conditions of the most adverse site, and therefore may be useful for rehabilitation of degraded sites. Differences among species and sites strongly suggest that species success depends on plantation site quality.  相似文献   

15.
鹅掌楸属植物研究进展及其繁育策略   总被引:6,自引:0,他引:6  
评述了鹅掌楸属2种植物在历史演化和生殖生物学、资源保护、引种及其杂交育种等领域的研究现状和存在的问题。并对其今后的繁育策略提出初步设想。  相似文献   

16.
马尾松是我国南方生态恢复与重建的先锋树种,具有耐干旱、耐贫瘠及速生丰产等优点,其人工林在我国森林资源总量中占举足轻重的位置,但纯林的养分循环差,易导致生产力低下;而研究马尾松光合生理特性及资源利用效率可以为马尾松人工林生产力的提高提供坚实的理论基础。文中综述马尾松光合生理特性及资源利用效率的研究进展,分析逆境胁迫对其光合生理特性及资源利用效率的影响,包括水分胁迫、热胁迫、酸雨胁迫、低磷胁迫及铝胁迫等。在全球变化背景下,研究马尾松光合生理特性与资源利用效率及其对逆境胁迫的响应,对于制定马尾松的管理与保护策略、挖掘其抗性潜力具有重要意义,可为马尾松林分生产力的提升及纯林改良策略的制定提供理论参考。  相似文献   

17.
对中国马褂木、北美鹅掌楸及其种间杂种F113个花果数量性状的研究结果表明:花被片长度(LP)等9个性状在类群间差异达显著或极显著程度,可用于类群识别;花药长度(LA)等11个性状在类群内个体间差异达极显著程度,说明类群内遗传多样性水平较高;杂种F1在雄蕊数(NS)等8个性状上,中国马褂木均表现出较强的遗传优势,花被片宽度(WP)等4个性状表现为偏父遗传或偏父超亲遗传;从性状间的相关性来看,聚合果气干质量主要由果宽决定,大花个体其雌蕊数较少但果实较大。采用聚类分析和主成分分析能有效地对3个类群进行识别。  相似文献   

18.
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   

19.
Plot sampling was conducted in the second cultivation areas ofLarix olgensis in Heilongjiang Province, China. By analyzing plot investigation data, wood properties, and kraft pulps of 840 plots and 248 sample trees in industrial plantations of L. olgensis on different sites, we examined the growth process of L. olgensis industrial plantation with suitable structure, the wood fiber feature, chemical composition, physical performance and pulp characteristics. It is suggested that site conditions have major effects on plantation growth, fiber contains, fiber length, rate between fiber length and fiber width, pulping rate and pulp physics intensity. The best site for L. olgensis industrial plantation growth is site class Ⅰ and site class Ⅱ, which are on lower locations. Site condition has an obvious influence on the wood characteristics. Within the range of site conditions and stand densities studied, the worse the site condition, the less the fiber contains, the shorter the fiber length, and the more the 1% NaOH extraction. This kind of relationship becomes more obvious as stand age increases. However, the influence of site condition on pulping rate and pulp physics intensity is not obvious. The result provides theoretical base for cultivation of industrial fiber plantation of L. olgensis.  相似文献   

20.
The potential of the country’s numerous indigenous tree species to address challenges facing the commercial forestry industry in South Africa is under-explored. Relevant issues include the rising demand for timber and non-timber forest products due to population and economic growth, minimal available land for expanding traditional commercial forestry operations, and known streamflow reduction impacts associated with introduced plantation tree species. However, little is known about the water use and corresponding growth rates of indigenous tree species, and consequently their potential as an alternative form of forestry and sustainable resource use. In this study, the water use, growth rates and resultant water-use efficiency of Vachellia kosiensis (Acacia kosiensis) (dune sweet thorn) were quantified within a mature stand of these trees situated on rehabilitated dune mining land in the Richards Bay area of South Africa. Hourly sap flow rates were measured over a two-year period in five trees, and tree heights and stem circumferences were recorded periodically throughout the monitoring period, to derive biomass increments. Rates of growth and water use were used to calculate water-use efficiency, defined as mass of utilisable (stem) wood produced per unit of water transpired. Results were compared with similarly sampled data for introduced plantation species, including Eucalyptus, Pinus and Casuarina. Results showed that the indigenous V. kosiensis trees used less than half the water used by introduced plantation species. The growth rates of individual V. kosiensis trees were unable to compete with introduced species; however, their higher tree density nevertheless yielded a mean annual increment of 10.3 m3 ha?1 y?1 (7.2 t ha?1 y?1). Furthermore, their correspondingly low water-use rates indicated that the indigenous trees had similar biophysical water-use efficiency values compared with genetically improved introduced tree species and highlighted their potential as an attractive land-use option in appropriate locations within water-constrained or dryland areas.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号