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1.
In the mid-1970s, Mozambique embarked on several forestry projects to promote and establish large plantation areas with eucalypt trees. The planted species included Corymbia citriodora, Eucalyptus camaldulensis, E. saligna and E. tereticornis. Similar to other regions of the world, pests and pathogens pose a significant threat to eucalypt plantations in Mozambique, but little is known regarding the diseases of trees in the country. The aim of this study was to provide the first detailed consideration of the possible disease problems affecting plantation- grown eucalypt species in the central and northern provinces of Mozambique. Isolates of fungal pathogens were obtained from material displaying disease symptoms collected during two field surveys conducted in 2010 and 2011. Representative fungal isolates were identified using DNA sequence data. Stem canker diseases caused by fungi in the Botryosphaeriaceae, Cryphonectriaceae and Teratosphaeriaceae, as well as leaf spots caused by species of Calonectria, Pilidiella, Pilidium and Phakopsora myrtacearum were commonly encountered. Their relative importance to the future of planation forestry in Mozambique is discussed.  相似文献   

2.
Heat treatment of Pinus pinaster and Eucalyptus globulus woods, two important species in Portugal, was performed in the absence of air by steaming, inside an autoclave, for 2–12 h at 190–210°C. Mass losses increased with treatment time and temperature reaching 7.3% for pine and 14.5% for eucalypt wood. The wood behaviour with moisture was improved. The equilibrium moisture content decreased by 46% for pine and 61% for eucalypt, the dimensional stability increased (maximum anti-shrinking efficiency in the radial direction of 57 and 90% for pine and eucalypt, respectively) and the surface wettability was lowered. In relation to mechanical properties, the modulus of elasticity was little affected (maximum decrease of 5% for pine and 15% for eucalypt) but the bending strength was reduced (by 40% at 8% mass loss for pine and 50% at 9% mass loss for eucalypt wood). The variation of properties was related to treatment intensity and mass loss but significant improvements could already be obtained for a 3–4% mass loss without impairing the mechanical resistance. The response of eucalypt was higher than that of pinewood. Heat treatment of eucalypt wood shows an interesting potential to improve the wood quality for solid timber products.  相似文献   

3.
Declining natural forests and growing demands for wood products are encouraging the rapid expansion of eucalypt farm forestry in Ethiopia, and Arsi Negelle district represents areas with recent plantation expansion in the Rift Valley area of Ethiopia. This study assessed trends in eucalypt planting over the last five decades, identified the determinants, and examined perceptions of local stakeholders towards this expansion in the district. Quantitative data were gathered through a household survey and farm level inventory. About 90% of the respondents had planted eucalypts, and 52% of them were engaged in planting since the late 1990s. About 11% converted cropland to eucalypt woodlots, which is also a growing trend in the area. Proximity to Arsi-Forest Enterprise (P?<?0.01) and area of land holding (P?<?0.01) positively and significantly affected both decision to plant and land area allocated to eucalypts plantings. Active labour in the family negatively and significantly (P?<?0.05) affected planting decisions, while education level of the household head positively and significantly (P?<?0.05) affected land area allocated to eucalypts plantings. Despite strong policy discouragement and perceived adverse ecological effects by the farmers themselves, 96% of them and 90% of the district experts support the expansion. Eucalyptus has become the most desired and planted tree genus, and economics not ecology appears to drive its expansion. Unless better alternative sources of cash income and substitutes for energy and construction materials are found, its expansion is likely to continue even at the expense of cropland. It is concluded that research is needed to fine-tune current eucalypt farm forestry practices to reduce the associated ecological externalities, rather than grossly banning eucalypt planting by smallholders.  相似文献   

4.
《Southern Forests》2013,75(2):139-144
Plantations of eucalypts (species of Eucalyptus and Corymbia), particularly in the tropics and Southern Hemisphere, have expanded dramatically during the course of the last 100 years. The nature of these plantations has changed substantially as selection, breeding, hybridisation, vegetative propagation and other innovative techniques have been introduced to improve planting stock. Although there are various examples of diseases and pests damaging early plantations, it is clear that separation of the trees from their natural enemies has resulted in exceptional performance. Not surprisingly, both the incidence and impact of diseases and pests in eucalypt plantations has increased over time. This has been due to the accidental introduction of pests and pathogens from areas where the trees are native to new environments. There are also growing examples of host-specific pathogens native to areas where eucalypts have been planted as non-natives, which have undergone sometimes surprising host jumps. These 'new pathogens' threaten not only plantation forestry based on non-natives, but also eucalypts and their relatives in areas where they grow naturally. There is little question that pests and pathogens are set to challenge eucalypt plantation forestry worldwide, more than ever before. In order to sustain profitable businesses based on eucalypt plantations, forestry companies will need to invest substantially in technologies enabling management of these pests and diseases.  相似文献   

5.
Our knowledge of the endophytic fungal community associated with needles of Sitka spruce (Picea sitchensis) is rather limited, which contrasts with the importance of this tree species for forestry in the UK. In our study, we focused on the detailed characterization of multiple isolates tentatively placed into the genera Nothophaeocryptopus and Rhizosphaera that were obtained from needles of Sitka spruce and co-occurring Norway spruce (Picea abies) and Douglas fir (Pseudotsuga menziesii) at four sites in Scotland and Wales. After a thorough analysis of their phenotype and analysis of two nuclear regions (ITS rDNA and gene for β-tubulin), we propose two species new to science and one new combination. Nothophaeocryptopus piceae was isolated from healthy green or brown needles from spruces and is currently known only as a sterile culture, but the taxonomic novelty is well supported by host affinity and results of molecular data analysis. Rhizosphaera minteri may also be distinguished based on the combination of host and molecular data, but morphologically, it is similar to R. pini. Finally, Hormonema merioides and R. pseudotsugae are found to be conspecific and a new combination R. merioides is proposed following the phylogenetic placement of this species. Our study highlights the importance of multiple approaches used in the identification of microfungi associated with coniferous needles. It is evident that morphologically identical fungi may represent distinct species differing in their host range and severity on the host. This study also provides a basis for future monitoring of these fungi associated with important coniferous forestry trees in the UK.  相似文献   

6.
《Southern Forests》2013,75(2):145-154
Eucalyptus globulus is the main eucalypt species grown in Australian plantations. The focus on seedling deployment systems, coupled with exploitation of large, open-pollinated base populations for breeding purposes over the last two decades, has required a detailed understanding of the reproductive biology of this species. We review our research on the reproductive biology of E. globulus, with a focus on its breeding system and advances made in seed production systems. While most improved seed is still obtained from open-pollinated seedling or grafted seed orchards, the development of the one-stop/single-visit pollination procedure has revolutionised the breeding and deployment of this species. The reduced costs of controlled pollination has meant full pedigree-control can now be maintained in large advanced-generation breeding populations and E. globulus is one of the few eucalypt species where large-scale production of manually pollinated seed for family forestry is being undertaken.  相似文献   

7.
The timing of bud development in ecodormancy is critical for trees in boreal and temperate regions with seasonally alternating climates. The development of vegetative buds and the growth of primordial shoots (the primordial shoot ratio) in Norway spruce were followed by the naked eye and at stereo and light microscopic levels in fresh-cut and fixed buds obtained by regular field samplings during the spring of 2007, 2008 and 2009. Buds were collected from 15 randomly selected trees (all 16 years old in 2007) of one southern Finnish half-sib family. The air temperature was recorded hourly throughout the observation period. In 2008 and 2009, initial events in the buds, seen as accumulation of lipid droplets in the cortex area, started in mid-March and were depleted in late April, simultaneously with the early development of vascular tissue and primordial needles. In mid-April 2007, however, the development of the buds was at least 10 days ahead as a result of warm spells in March and early April. Variation in the timing of different developmental phases within and among the sample trees was negligible. There was no clear one-to-one correspondence between the externally visible and the internal development of the buds. The dependence of the primordial shoot ratio on different types of temperature sum was studied by means of regression analysis. High coefficients of determination (R(2)?≈?95%) were attained with several combinations of the starting time (beginning of the year/vernal equinox), the threshold value (from -3 to +5 °C), and the time step (hour/day) used in the temperature summation, i.e., the prediction power of the primordial shoot ratio models turned out to be high, but the parameter estimate values were not unambiguous. According to our results, temperature sums describe the growth of the primordial shoot inside the bud before bud burst. Thus, the results provide a realistic interpretation for the present phenological models of bud development that are based on temperature sums and external observations of bud burst only, and they also provide new tools for improving the models.  相似文献   

8.
Summary The temperature-time-location relationships during steam conditioning and pressure treatment of timber poles using ammoniacal copper arsenate (ACA) have been studied and a new mathematical model that incorporates both the thermal properties of the poles and the parameters of the treatment process is discussed. Prediction equations and charts are presented that show the minimum required steaming time to satisfy the 1982 Rural Electrification Authority (REA) purchase specification, i.e. a center temperature above 150 °F (65.5 °C) for 2 hours. A six hour steaming time, commonly used for ACA treatment, has been found to be too short to bring poles with diameters larger than about 40 cm to the required sterilization conditions. Therefore longer steaming times, predicted using the methods given here, are recommended. The temperature of the preservative used does not appear to be a major factor in determining the maximum temperature achieved at the center of a pole, but it can influence the length of time the pole is above 65.5 °C.Symbols D pole diameter, cm - k1 rate of surface temperature change during vacuuming, °C/h - K2 rate of surface temperature change early in the pressure period, °C/h - J0 Bessel function of the first kind of order zero - J1 Bessel function of the first kind of order one - r radial location in a pole measured from the center, cm - R pole radius, cm - T interior temperature of a pole during preservative treatment, °C - Tf final preservative temperature, °C - Tmid average of the steam and the final preservative temperatures, °C - t0 initial temperature of a pole, °C - Ts temperature of the steam used for conditioning the poles, °C - T1 surface temperature at the end of the vacuum period, °C - t time measured from the opening of the steam valve for steaming, h - tabove time the center of a pole remained above 65.5°C during preservatives treatment, h - tc1 total time required for the surface temperature to reach Tf, °C - tpr time elapsed at which initial vacuuming stops and pressure is applied, h - tstm minimum required steaming time used, h - tvc time elapsed at which initial vacuuming starts, h - thermal diffusivity, cm2/h - n Roots of a particular characteristic equation - d the time delay period between initial flow of steam and surface temperature response, h  相似文献   

9.
Clonal forestry captures genetic gain generated by skillful selection and is now well recognized as a method for mass production of desired trees to obtain increased economic benefits. In Eucalyptus, clonal plantations have enhanced the productivity twofold, compared to plantations of unimproved seed origin. The present investigation was carried out to assess the genetic relationship of 41 eucalypt clones using the intersimple sequence repeat (ISSR) marker system. The ISSR-derived dendrogram and principal coordinate analysis (PCA) clustered 39 clones into two groups of E. camaldulensis and E. tereticornis in agreement with their taxonomic classification. Further, a total of three clone specific diagnostic markers and five unique profiles were identified using five ISSR primers. The eucalypt clones analyzed in the present investigations are derived from the breeding populations of both the species and are presently being used for large-scale plantation and hybridization studies. The molecular marker based clonal discrimination can be used to avoid duplication of clones and quality control of planting stock.

[Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Sustainable Forestry for the following free supplemental resource(s): ISSR Profiles of Eucalyptus Clones]  相似文献   

10.
《Southern Forests》2013,75(4):199-212
Eucalyptus nitens requires a sufficiently cold winter to produce flower buds. In areas in South Africa where E. nitens commercial plantations as well as breeding and production seed orchards are located, winter chilling is often insufficient for floral bud initiation. Hence, under such conditions, E. nitens floral bud and seed crops are poor and inconsistent. The local industry is almost entirely dependent on paclobutrazol (PBZ) applications for encouraging flowering in E. nitens seed orchards. Between 2008 and 2010, an experiment was conducted to investigate the potential of overhead irrigation (sprinkling) as a means of supplementing winter chilling to improve floral bud production in E. nitens. The treatments included three levels of sprinkling (nil, 10 weeks and 16 weeks duration), two levels of PBZ (nil, 0.025 g a.i. per mm basal stem circumference) and two grafted clones (prolific flowerer and shy-flowerer). Sprinkling reduced E. nitens daytime bud temperatures by as much as 16.2 °C on warm, dry winter days. In 2009 (cold winter) and 2010 (warm winter), sprinkling increased chilling accumulation by 44% and 72% (nil versus maximum sprinkling), respectively. In 2009, in the absence of PBZ, sprinkling resulted in a higher percentage of trees of either clone producing umbels (flower buds) compared with the control. In the warmer 2010 winter, sprinkling again increased flowering, with the number of flowering shoots and umbels per tree being significantly higher than the control at p < 0.05. In both 2009 and 2010, PBZ showed a strong additive effect to winter chilling on E. nitens floral bud production. The E. nitens clone × chilling × PBZ flowering interaction was complex and warrants more detailed investigation in future. Overhead sprinkling offers a practical method of supplementing winter chilling and improving floral bud production in high-chill-requiring temperate eucalypt species such as E. nitens.  相似文献   

11.
桉树人工林生态问题已成为森林与环境、林业持续发展中社会各界共同关注的焦点之一。通过在广西主要桉树人工林造林区设置3个监测点,进行pH值、高锰酸钾指数（CODMn）、5日生化需氧量（BOD5）和悬浮物（SS）的多年定位监测。监测数据表明：桉树造林后林区水样CODMn、BOD5、SS、pH值的参数均发生了显著的变化;宁明、...  相似文献   

12.
Summary

Eucalypt plantations in India are an important source of fiber for paper making and fuel for local villagers. Large areas of land have supported eucalypt plantations for several rotations, and productivity has generally been declining through successive rotations. In 1997, we initiated a project to examine site management options as a way to improve the productivity of these sites. We established a large experimental infrastructure at each of four sites in Kerala, consisting of up to five separate fully randomized block experiments at each site, examining interrotation management options (organic matter manipulation, N and P fertilizer input, legume cover cropping, weed control). Two of the sites were typical lowland plantations with Eucalytus tereticornis, and the other two sites were typical upland plantations with Eucalytus grandis. Following treatments, we monitored plantation productivity and impacts on soil and nutrient cycling for one full rotation (6.5 years). We found it is possible to increase the volume growth of E. grandis by up to 48%, and E. tereticornis by up to 268% through a combination of optimum site practices (mostly weed control and nutrient addition), but productivity responses are dependent on site-specific factors. Key outcomes of this research are presented, with special reference to application in the broader context of tropical eucalypt plantations.  相似文献   

13.
There is increasing interest worldwide in using tree harvesting biomass as an energy source. Bark retained on logs is commonly used as an energy source, but is generally removed from eucalypt logs during harvest. In order to evaluate the potential use of eucalypt bark as fuel, there is a need for information on the productivity and cost implications of retaining eucalypt bark during harvest operations. The study examined the impact of retaining bark on logs on the productivity and costs of a whole?tree to roadside harvesting system in a short?rotation Eucalyptus nitens plantation in Australia being harvested for pulp logs. Trees were felled and bunched with a feller?buncher in spring, then left infield for four weeks to promote bark adhesion and reduce bark loss. A skidder extracted the trees to roadside where a processor processed them to predominantly 10?m logs. Machine productivities were calculated from estimated tree and log volumes and cycle times recorded from video recordings. The feller?buncher's productivity (65 m3 PMH0?1) was less than expected as it appeared to be underpowered to handle the larger trees on the study site. The skidder's productivity (56 m3 PMH0?1) was comparable to those reported in studies under similar conditions and with bark retained. The roadside processor's productivity (25 m3 PMH0?1) was lower than expected. This was believed to result from the operator separately stacking 10?m and 5?m logs, and the lower feed speed resulting from slippage due to the reduced feed roller pressure used in the study to reduce bark loss. Future research could identify feed rollers that increase feed speed while retaining bark. Harvest system costs (AUD18 GMt?1) were similar to those reported for a eucalypt roadside processing trial where bark was removed. These results suggest that retaining bark on the logs at roadside did not affect the harvesting system's productivity or costs.  相似文献   

14.
Ralstonia solanacearum sensu lato causes bacterial wilt in many agronomic crops and tree species economically important worldwide. It is a species complex that has been divided into phylotypes and sequevars, commonly related to geographic distribution. Knowledge of the phylotype composition and genetic variability in populations of this phytopathogenic bacterium is useful for implementing effective control measures. In a survey conducted in 2019, six bacterial strains were obtained from wilted Eucalyptus urophylla trees in plantations located in the municipality of Dom Eliseu, Pará state, Brazil. Multiplex PCR based on the internal transcribed spacer (ITS) indicated that the bacterial strains belonged to two different species, namely R. pseudosolanacearum (phylotype I) and R. solanacearum (phylotype II). In a phylogenetic analysis, the nucleotide sequence of the endoglucanase (egl) gene from eucalypt strains of phylotype I clustered together with sequevar 18 sequences from GenBank. Separation of the strains into two different species was confirmed by repetitive element palindromic PCR (rep‐PCR). Pathogenicity tests demonstrated that the R. solanacearum and R. pseudosolanacearum strains recovered from E. urophylla cause disease in both tomato and eucalypt plants. Until now, only R. solanacearum (Phylotype II) has been reported causing wilt symptoms on Eucalyptus spp. in Brazil. Therefore, the presence of R. pseudosolanacearum and a need for better understanding of its genetic and aggressiveness variability as well as possible differences between the two species should be considered in breeding programmes aimed at the deployment of host resistance.  相似文献   

15.
During 2001, a series of four site–taxa interaction trials was established in the warm temperate (mean annual temperature range 16–19 °C) forestry climatic zone of KwaZulu-Natal (KZN), South Africa. The main objective was to investigate the commercial forestry potential of a range of alternative Eucalyptus and Corymbia taxa for moderately dry (mean annual precipitation < 850 mm) sites within the zone. At rotation end, all trials received final standing tree measurements. At one of the sites (Rockvale), trees of eight promising alternative taxa were felled, stem measurements and wood samples taken, and wood and fibre productivities determined. On the basis of tree growth and wood and fibre production, C. citriodora subsp. variegata, C. henryi, E. badjensis, E. benthamii and E. dorrigoensis (listed alphabetically) demonstrated the greatest potential as commercial alternatives for moderately dry sites in the KZN warm temperate zone. The majority of these taxa showed strong site specificity. Eucalyptus benthamii was the only taxon showing high growth adaptability to the entire range of site conditions applied in the series. The non-susceptibility of C. citriodora subsp. variegata and C. henryi to the current topical insect pests Thaumastocoris peregrinus, Leptocybe invasa and Glycaspis brimblecombei elevates the appeal of these taxa as potential alternative planting choices for moderately dry sites within lower altitude (<1 100 m asl) areas of the climate zone. The matching of the most promising alternative taxa in the series to the range of sites encountered in moderately dry areas of the KZN warm temperate forestry zone is discussed in this paper.  相似文献   

16.
The effects of temperature on mechano-sorptive (MS) creep of delignified hinoki wood (Chamaecyparis obtusa Endl.) were investigated using longitudinal (L) and radial (R) specimens during adsorption and desorption over the temperature range of 20°–80°C. The results were compared with those of stepwise delignified specimens tested at a constant temperature of 20°C. It was found that the effects of temperature on the MS creep of delignified specimens are more remarkable than for untreated specimens. The tendencies of increasing MS creep with temperature, delignification, and their combination were observed. The increase in MS creep for L specimens was relatively small and almost equal in both adsorption and desorption processes, while for R specimens the MS creep was small in desorption, but significantly different in adsorption. In addition, good correlation was observed between the MS coefficient (K) and instantaneous compliance (J 0). The increase in MS creep occurs as a result of temperature increase or decrease in lignin content, or their interacting effects. However, in the case of desorption for R specimens, the increase of MS creep was unexpectedly small due to a remarkably increased J 0. Part of this report was presented at the 15th Annual Meeting of the Chubu Branch of the Japan Wood Research Society in Fukui, October 2005  相似文献   

17.
The Eucalyptus pathogen Quambalaria eucalypti has been reported from several subtropical and tropical countries of the Southern Hemisphere. During the course of a nationwide monitoring programme aimed at the detection of pathogens in commercial eucalypt plantations in Portugal, Q. eucalypti was found affecting Eucalyptus globulus. The identity of the pathogen was confirmed by sequence analyses of the internal transcribed spacer (ITS) region of the rDNA operon, as well as morphological characteristics. Quambalaria eucalypti is widespread throughout the eucalypt‐producing areas of Portugal. Pathogenicity studies revealed that different host genotypes showed various degrees of susceptibility to the pathogen. To our knowledge, this is the first report of Q. eucalypti on Eucalyptus spp. in Portugal and in the Northern Hemisphere.  相似文献   

18.
George  B.H.  Brennan  P.D. 《New Forests》2002,24(2):147-163
Effective weed control is an essential management task in establishing commercial tree plantations. Much of the current weed control strategies employed in Australian forestry relies on the use of available herbicides. However, given community concern regarding the use of herbicides, investigation of alternative weed control methods is warranted. We tested the ability and cost-effectiveness of mechanical (hand weeding and inter-row slashing), mulching (sawdust over newsprint, woodchips and jute), cover crops and herbicide applications for weed control in establishing eucalypt plantations. Jute matting and herbicide treatments reduced weed competition and increased seedling growth to age 2 years in plantations of Eucalyptus dunnii and Eucalyptus saligna in northern NSW, Australia. Growth increased by 269 % (Experiment 1) and 196 % (Experiment 2) in the Jute and by 216 % (Experiment 2) in the Herbicide treatments when compared to the control (no weed control) at 2 years age. As the Jute material deteriorated, after nearly 2 years, weed cover increased and there were significantly more weeds present in the Jute treatment compared to the Herbicide treatment. Jute matting costs approximately 15 times more than the herbicide regime used and, therefore, could not presently be considered a viable option for weed control in commercial eucalypt plantations. Other weed control treatments, including hand weeding, sawdust and woodchip mulches, slashing and sowing cover crops did not effectively control weeds and did not improve survival or increase seedling growth to age 2 relative to the control. We conclude that herbicides remain the most cost-effective weed control option available to commercial growers of eucalypt plantations.  相似文献   

19.
The effect of temperature upon nighttime respiration was examined on four different sized sample trees in a 17-year-old hinoki cypress (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.) stand over two years. Seasonal changes inQ 10 values and their responses to mean temperature were investigated. On the basis of the monthly relationships between nighttime respiration (r) and temperature inside a chamber (θ),r=r 0exp (kθ), theQ 10 value (=exp(10k)) was calculated. TheQ 10 values were high (Q 10≥3.0) in winter when mean air temperature was low, and gradually decreased toward summer (Q 10≤1.5) through spring with increasing temperature. TheQ 10 values were negatively correlated with mean air temperature. The response ofQ 10 values to mean air temperature was described by a single equation, regardless of tree size. This result, which might be characteristic of this species, shows that respiration ofC. obtusa trees is promoted by slight increases of air temperature in winter season. On the other hand, temperature sensitivity of total respiration reduced during growing season when ambient temperature was high. These chaning temperature sensitivity according to seasons may depend on the seasonal change of the ratio of growth respiration to total respiration. It is concluded that changes in temperature due to changing seasons not only change respiration rate, but also change the response of respiration rate to temperature by shiftingQ 10 values.  相似文献   

20.
《Southern Forests》2013,75(3-4):193-206
Atmospheric deposition was assessed at two sites over a four-year period in post-canopy-closure (mature) Eucalyptus stands in the northern Dukuduku and southern KwaMbonambi commercial plantation forestry areas of Zululand, South Africa. The aim of this study was to determine the magnitude and relevance of nutrient addition with rainfall, throughfall and stemflow to commercial forestry in this region. Canopy cation exchange was used with rainfall and canopy drainage to derive wet, dry and total atmospheric deposition. Nutrient concentrations measured in the rainfall, throughfall and stemflow varied widely throughout the study period, and between sources and sites. Rainfall was slightly acidic at both sides, but became less acidic upon passing through the tree canopies. Canopy exchange and collection of dry deposition resulted in increased cation concentrations under the tree canopy, while the canopy generally absorbed nitrogen (N), from the rainfall, reducing the below canopy concentrations. Atmospheric deposition was shown to be responsible for large quantities of nutrients added to the eucalypt stands at each site. Annualised deposition averaged across all years at each site amounted to N, calcium, magnesium, and potassium (K) fluxes of 11.0, 6.0, 2.7 and 10.2 kg ha?1 y?1 at Dukuduku and 10, 10.6, 7.5 and 18.8 kg ha?1 y?1 at KwaMbonambi, respectively. Organic N fluxes contributed a further 8.1 kg ha?1 y?1 at Dukuduku and 7.1 kg ha?1 y?1 at KwaMbonambi to the total N deposition. Although K deposition values were high, additions of all other nutrients, although also high, were within the ranges reported in local and international research. Over the course of a full rotation, the atmospheric deposition levels recorded at these sites may have potential to supply a large proportion of the nutrients that are lost during stem-wood harvesting. This study adds value to understanding of nutritional sustainability of fast-growing plantation forests, demonstrating the importance of atmospheric deposition as a nutrient addition source to plantation-grown eucalypts along the Zululand coastal plain.  相似文献   

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