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南酸枣苗木培育及造林技术 总被引：1，自引：0，他引：1
从南酸枣的采种、育苗、造林、抚育间伐、主要病虫害防治等技术措施,总结了南酸枣苗木培育及造林关键技术,旨在为南酸枣苗木培育及造林提供技术指导。 相似文献
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南酸枣天然林生长规律研究 总被引：1，自引：1，他引：0
对南酸枣天然及人工状态下的生长过程研究表明 ,南酸枣天然林胸径生长高峰期在 15年生左右、树高生长高峰期在15～ 2 0年生 ,材积生长高峰期在 2 0年生左右 ,南酸枣人工林的胸径、树高生长峰值比天然林的出现时间早 8～ 10a,峰值大。经过人工培育 ,南酸枣具有更强的速生性 ,人工造林效果好 ,在森林分类经营中具有广阔的发展前景 相似文献
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优良树种南酸枣研究综述 总被引：2，自引：0，他引：2
总结了南酸枣的国内资源状况、种苗培育与移栽、造林技术、不同类型的混交林效果等各个方面的研究情况,并根据研究现状提出了今后开展南酸枣研究的几点建议. 相似文献
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造林密度对毛红椿等阔叶用材树种早期生长的影响 总被引：2，自引：0，他引：2
开展了毛红椿(Toona ciliata var. pubescens)、光皮桦(Betula luminifera)、乳源木莲(Manglietia yuyuanensis)、杂交马褂木(Liriodendron chinense.× L.tulipifera)、桤木(Alnus cremastogyne)和南酸枣(Choerospondias axillaria)6种优良阔叶用材树1 666、2 500、3 333株/hm~23种造林密度试验,对4年生林分的观测结果显示:造林密度为1 666株/hm~2桤木林分胸径显著高于造林密度为3 333株/hm~2和2 500株/hm~2的桤木林分;造林密度对其它各树种各生长指标的影响不显著.光皮桦和桤木的生长较快,乳源木莲生长最慢.研究认为,以培育中、大径材为目的的用材林,光皮桦、桤木初植密度宜定在1 666株/hm~2;毛红椿、杂交马褂木、南酸枣初植密度以1 666株/hm~2和2 500株/hm~2为宜,乳源木莲则以2 500株/hm~2和3 333株/hm~2为宜. 相似文献
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Peng-fei Wu Xiang-qing Ma Mulualem Tigabu Yong Huang Li-li Zhou Liping Cai Xiao-long Hou Per Christer Oden 《林业研究》2014,25(2):377-383
Plantations of eucalypts as short-rotation tree crops are rapidly expanding in tropical and sub-tropical regions, including southern China, where the soils are acidic and available phosphorus(P) is limited. We investigated seedling growth, dry matter accumulation, and the dynamics of photosynthetic rate and chlorophyll content of seven Eucalyptus species/hybrids(E. dunnii, E. grandis, E. grandis × E. camaldulensis, E. urophylla × E. camaldulensis, E. urophylla × E. tereticornis, E. grandis × E. tereticornis, E. urophylla × E. grandis) in response to different levels of P supply(0, 6, 12 and 18 mg?kg-1 KH2PO4). The photosynthetic rate and the chlorophyll content significantly declined as the P supply declined in almost a linear fashion for all species as the P stress period extended. In the absence of P supply, height growth of seedlings of all species was significantly impaired, while root collar diameter growth and whole plant dry matter accumulation was not affected by the level of P supply in most of the species. Significant inter-species variations in growth, dry matter accumulation and photosynthetic rate in response to P supply were detected. Eucalyptus dunnii had the lowest growth performance across all levels of P supply while E. urophylla × E. tereticornis showed superior growth performance. From a practical point of view, E. urophylla × E. tereticornis is suggested as a candidate hybrid for planting on slightly P-deficient sites in southern China while E. dunnii, being a slow-growing species, is not suitable for short-rotation plantation. On plantation sites where severe P deficiency exists, P fertilization needs to be considered to boost rapid growth of seedlings so as to meet the management objectives of short-rotation plantation. 相似文献
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The study was conducted at Zengena forest, a fragmented remnant montane forest in northwestern Ethiopia, which surrounds Lake Zengena. The purpose was to assess the species composition, diversity and the regeneration status of woody plants. A total of 27 plots of 20 m × 20 m were sampled along the line transects laid down the altitudinal gradient from the edge of the forest encompassing the lake to the edge of the lake in eight aspects. In each plot, woody species were counted and the diameter at breast height and the height of trees and shrubs were measured. A total of 50 woody species belonging to 31 families were found, of which 17(34%) were trees, 7(14%) trees or shrubs, 23(46%) shrubs and 3(6%) lianas. The overall Shannon-Wiener diversity and evenness indices of woody species were 2.74 and 0.7, respectively. Clausena anisata had the highest relative density(23.5%), Rapanea rhododendroides the highest relative frequency(6.5%) and Prunus africana the highest relative dominance(45%) and importance value index(IVI, 51.6). The total basal area and density of woody plants were 22.3 m2?ha-1 and 2,202 individuals?ha-1, respectively. The population structure showed variations among woody plants and revealed varied regeneration patterns of different species. The importance value index and population structure revealed that some species are threatened and need prioritization for conservation measures. The results suggest that remnant forest patches in the highlands of northern Ethiopia host several woody plant species that are almost disappearing in other areas due to deforestation. 相似文献
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Fuel properties and combustion characteristics of some promising bamboo species in India 总被引：1，自引：0，他引：1
We investigated the fuel characteristics of five important bamboo species viz., Dendrocalamus strictus, D. brandisii, D. stocksii, Bambusa bambos and B. balcooa. The selected species cover more than 85% of the total growing stock of bamboo in India. Basic density varied from 0.48 to 0.78 g?cm-3 among the bamboo species studied. Ash content, volatile matter content and fixed carbon content ranged between 1.4%-3.0%, 77.2%-80.8% and 17.6%-21.1%, respectively. Variation in calorific value(18.7-19.6 MJ?kg-1) was marginal. Fuel value index varied widely(586-2120) among bamboo species. The highest calorific value(19.6 MJ?kg-1) and fuel value index(2120) were found in B. balcooa. Ash elemental analysis revealed that silica and potassium are the major ash forming minerals in bamboo biomass. Silica content ranged from 8.7% to 49.0%, while potassium ranged from 20.6% to 69.8%. We studied combustion characteristics under oxidizing atmosphere. Burning profiles of the samples were derived by applying the derivative thermogravimetric technique which is discussed in detail. The five bamboo species were different in their combustion behaviour, mainly due to differences in physical and chemical properties. We compare fuel properties, ash elemental analysis and combustion characteristics of bamboo biomass with wood biomass of Eucalyptus hybrid(Eucalyptus tereticornis × Eucalyptus camaldulensis). 相似文献
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The city of Tehran,like many polluted metropolises of the world,has higher emissions of greenhouse gases than other cities in Iran,due to heavy consumption of fossil fuel and landuse changes.To estimate carbon sequestration in two 40 year-old stands of planted Cupressus arizonica and Fraxinus rotundifolia in degraded lands surrounding Tehran,sampling of above-and below-ground biomass,soil(at two depths of 0-15 and 15-30 cm),and leaf litter was done by systematic random sampling.The total carbon stocks of C.arizonica and F.rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1.The aboveground biomass with 233.16(71%)Mg·ha-1 in C.arizonica and88.16(58.50%)Mg·ha-1 in F.rotundifolia contributed the most shares to carbon sequestration.The diameter at breast height,total height,basal area,total volume,and biomass of C.arizonica were significantly(p0.01)higher than those of F.rotundifolia.Also the depth of 0-30 cm of soil contributed between 18.29%and 32.15%of total ecosystem carbon,respectively.The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars,respectively.Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land,the current status quo.These stands can absorb atmospheric CO2 at different rates,thus tree species selection and stand development should be considered in planning future afforestation projects. 相似文献
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Zhi-liang Zhang Guo-dong Liu Fu-cang Zhang Cai-xia Zheng Fu-quan Ni Yin-hong Kang Yun Zeng 《林业研究》2014,25(2):365-375
A pot experiment was conducted to investigate the effects of nitrogen content [N1(no fertilizer), N2(0.15 g?kg–1), and N3(0.3 g?kg–1)] on the growth and the hydraulic characteristics of peach seedlings under different soil moisture conditions(W1, W2 and W3, in which the soil water content was 45% to 55%, 60% to 70%, and 75% to 80% of the field water capacity, respectively) by using a specialized high pressure flow meter with a root chamber and a coupling, which was connected to plant organs. Leaf area and leaf hydraulic conductivity(KL) increased significantly in the seedlings because of increased soil moisture and N content. KL increased with leaf area. A linear correlation was documented between KL and leaf area. KL was higher in the morning and began to decline sharply after 16:00, at which KL declined after an initial increase. Soil moisture and N content enhanced shoot(Ks) and root(Kr) hydraulic conductivities, thereby improving the low soil moisture condition to a large extent. Ks and Kr of the seedlings were reduced by 32% and 27% respectively in N1, and by 14.7% and 9.4%, respectively in N2, and both in W1, compared with the control treatment. N3 had no significant effect on Ks and Kr under similar conditions. Linear negative correlations were observed between Kr and the excised root diameter as well as between Ks and the shoot stem diameter. The shoot-to-root ratio increased with increase in N content. The shoot-to-root ratio in N3 was increased by 14.37%, compared with N1 in W1 as well as by 12% and 4.39% in W2 and W3, respectively. Knowledge of the effects of soil moisture and N fertilizer on hydraulic characteristics and growth is important. Our results provide basic guidelines for the implementation of water-saving irrigation and fertilization management of nursery stock. 相似文献
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Jesús Jaime Guerra-Santos Rosa María Cerón-Bretón Julia Griselda Cerón-Bretón Diana Lizett Damián-Hernández Reyna Cristina Sánchez-Junco Emma del Carmen Guevara Carrió 《林业研究》2014,25(1):129-134
We report the results of carbon stored in soil and aboveground biomass from the most important area of mangroves in Mexico,with dominant vegetation of Red mangrove(Rhizophora mangle L.),Black mangrove(Avicennia germinans L.),white mangrove(Laguncularia racemosa Gaertn.)and button mangrove(Conocarpus erectus L.).We sampled soils with high fertility during the dry season in 2009 and 2010at three sites on Atasta Peninsula,Campeche.We used allometric equations to estimate above ground biomass(AGB)of trees.AGB was higher in C.erectus(253.18±32.17 t·ha-1),lower in A.germinans(161.93±12.63t·ha-1),and intermediate in R.mangle(181.70±16.58 t·ha-1)and L.racemosa(206.07±19.12 t·ha-1).Of the three studied sites,the highest absolute value for AGB was 279.72 t·ha-1in button mangrove forest at any single site.Carbon stored in soil at the three sites ranged from36.80±10.27 to 235.77±66.11 t·ha-1.The Tukey test(p0.05)made for AGB was higher for black mangrove showed significant differences in soil carbon content between black mangrove and button mangrove.C.erectus had higher AGB compared with the other species.A.germinans trees had lower AGB because they grew in hypersaline environments,which reduced their development.C.erectus grew on higher ground where soils were richer in nutrients.AGB tended to be low in areas near the sea and increased with distance from the coast.A.germinans usually grew on recently deposited sediments.We assumed that all sites have the same potential to store carbon in soil,and then we found that there were no significant differences in carbon content between the three samples sites:all sites had potential to store carbon for long periods.Carbon storage at the three sampling sites in the state of Campeche,Mexico,was higher than that reported for other locations. 相似文献
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A microbial inoculant, known as effective microorganisms(EM), was applied to determine its efficacy on seed germination and seedling growth in the nursery of Acacia auriculiformis A Cunn. ex Benth. The seedlings were grown in a mixture of sandy soil and cow dung(3:1) and kept in polybags; EM was poured at different concentrations(0.1%, 0.5%, 1%, 2%, 5% and 10%). Seed germination rate and growth parameters of seedlings – shoot and root lengths, fresh and dry weights of shoots and roots, vigor, volume, and quality indices and sturdiness – were measured. The nodulation status influenced by EM was also observed, along with the measurement of pigment contents in leaves. The highest germination rate(72%) was observed in 2% EM solution while the lowest(55%) was found in control treatment. The highest shoot and root lengths(30.6 cm and 31.2 cm respectively) were recorded in 2% EM and were significantly(p 0.05) different from control. Both fresh and dry weights of shoots were maximum(8.66 g and 2.99 g respectively) in 2% EM, whereas both fresh and dry weights of root were maximum(2.56 g and 1.23 g respectively) in 5% EM solution. Although the highest vigor index, volume index, and sturdiness(4450, 628 and 67.5 respectively) were found in 2% EM, the highest quality index(0.455) was found in 5% EM solution. The nodule number was higher at a very low(0.5%) concentration of EM but it normally decreased with the increase of concentration. The contents of chlorophyll a, chlorophyll b, and carotenoid were maximum(43.26 mg?L-1, 13.56 mg?L-1and 17.99 mg?L-1 respectively) in 2% EM. Therefore, low concentration of EM(up to 2%)can be recommended for getting maximum seed germination and seedling development of A. auriculiformis in the nursery. 相似文献
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Kaushalendra Kumar Jha 《林业研究》2014,25(1):75-86
Teak(Tectona grandis Linn.f.) ranks among the top five tropical hardwood species and is being promoted for use in plantations in its non-native range due to its high economic value.However,there is a general lack of data on ecosystem functioning of teak plantations.We aimed at understanding storage and flux of nutrients related to young plantations of teak.Cycling of nitrogen(N) and phosphorus(P) in a chronosequence of plantations(1,5,11,18,24 and 30 years) was studied in the Moist Deciduous Forest Region of North India with the objective of investigating the nutrient cycling pattern at younger age since the current trend of harvesting age of the species in several tropical countries is being drastically reduced for quick return from this high value crop.Standing state,nutrient uptake,nutrient return and nutrient retranslocation in these plantations were estimated by tree harvesting and chemical analysis methods.The range of total standing nutrient across all these plantations was 20.3 to 586.6 kg·ha-1 for N and 5.3 to 208.8 kg·ha-1 for P.Net uptake of N ranged from 19.4 to 88.9 kg·ha-1·a-1 and P from 3.8 to 18.1 kg·ha-1·a-1.Retranslocation of N and P among all the stands ranged from 8.7 to 48.0 kg·ha-1·a-1 and 0.01 to 3.5 kg·ha-1·a-1,respectively.Range of total nutrient return was 25.8 to 91.3 kg·ha-1·a-1 for N and 2.7 to 10.1 kg·ha-1·a-1 for P.N and P use efficiency was between 107.4 and 192.5 g dry organic matter(OM) g-1 N,and 551.9 and 841.1 g OM g-1 P,respectively.The turnover time ranged from 2.04-13.17 years for N and between 2.40-22.66 years for P.Quantity of N and P in the soil nutrient pool ranged from 2566.8 to 4426.8 kg·ha-1 and 372 to 520 kg·ha-1,Storage and flux of components in different plant parts of different aged plantations were assessed and depicted in compartment models.Percentage storage in soil,litter and vegetation ranged from 82% to 99%,0.6% to 2.4% and 0.5% to 15% for N,respectively,and from 63% to 98%,0.5% to 2% and 1% to 35% for P,respectively.This information could be useful in managing external nutrient manipulation to crops of different ages for optimum biomass production or carbon sequestration. 相似文献
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Amit Kumar Tripathi Uma Shankar 《中国林学(英文版)》2014,(4):227-246
Background： The ＇Khasi hill sal＇ forest ecosystem in Meghalaya, India represents the easternmost limit of sal distribution. We tested if tree diversity and compositional heterogeneity of this ecosystem was higher than other sal-dominated forests due to moister environment. Methods： Vegetation was sampled in 11 transects of 10 m width and up to 500 m length covering 5.2 ha area. All stems ≥10 cm girth at breast height were enumerated. Results： We found a pattern of mixed dominance of Shored robusta （sal） and Schima wollichii and co-dominance of Pinus kesiyo and Careya arborea. The Shannon＇s diversity index （H＇） was 3.395 nats. This value is remarkably high and competitive to that of moist sal forests of eastern Himalayan foothills and sal-dominated forests of Tripura. A high value of H＇ was manifested by： a） high species richness （S = 123）, b） good equitability （70.6%）, c） ＇fair＇ resource apportionment, and d） abundance of rare species （84% species with less than one per cent of total individuals, 67% species with two or less individuals ha-1 and 59% species with one or less individuals ha-1）. The compositional heterogeneity was ＇fair＇ （Whittaker＇sβw = 3.15）. The presence of Fagaceae with six species commanding 4.3% of importance value （IVl） and of a pine （P. kesiya） in sal forest was remarkable. As many as 58 species showed ＇low density （〈 10 individuals ha-1）, uniform dispersion＇, five species achieved ＇higher density （〉 10 individuals ha-l）, uniform dispersion＇ and six of the top 10 species were ＇clumped＇. The forest showed an exponential demographic curve illustrating ＇good＇ regeneration of an expanding community. Vertical stratification was simple with a poor canopy and fair subcanopy, which together with low basal area （15.65 m2 . ha-1 for individuals ≥ 10 cm gbh） indicated logging of mature sal trees in the past. Conclusions： The ＇Khasi hill sal＇ forest ecosystem is richer in alpha and beta diversi 相似文献
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XiuHai Zhao ;Javier CorraI-Rivas ;ChunYu Zhang ;Hailemariam Temesgen ;Klaus v Gadow 《中国林学(英文版)》2014,(2):61-70
This contribution complements Forest Ecosystems＇ Thematic Series on ＂Forest Observational Studies＂. We provide essential clarification regarding the definition and purpose of long-term field studies, review some of the extensive literature and discuss different approaches to collecting field data. We also describe two newly established forest observational networks that serve to illustrate the scope and diversity of forest field studies. The first is a large-scale network of forest observational studies in prominent natural forest ecosystems in China. The second example demonstrates observational studies in mixed and uneven-aged pine-oak forests which are selectively managed by local communities in Mexico. We summarize the potential for analysing and modeling forest ecosystems within interdisciplinary projects and provide argumentation in favour of long-term institutional commitment to maintaining forest observational field studies. 相似文献