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1.
Worldwide, the land area devoted to timber plantations is expanding rapidly, especially in the tropics, where reptile diversity is high. The impacts of plantation forestry and its management on native species are poorly known, but are important, because plantation management goals often include protecting biodiversity. We examined the impact of pine (Pinus caribaea) plantations, and their management by fire, on the abundance and richness of reptiles, a significant proportion of the native biodiversity in tropical northern Australia, by (i) comparing abundance and diversity of reptiles among pine plantations (on land cleared specifically for plantation establishment), and two adjacent native forest types, eucalypt and Melaleuca woodlands, and (ii) comparing reptile abundance and richness in pine forest burnt one year prior to the study to remove understorey vegetation with pine forest burnt two years prior to the study. We also examined the influence of fire on reptile assemblages in native vegetation, by comparing eucalypt woodland burnt two years prior to the study and unburnt for eight years. To quantify mechanisms driving differences in reptile richness and abundance among forest types and management regimes, we measured forest structure, the temperatures used by reptiles (operative temperature) and solar radiation, at replicate sites in all forest types and management regimes. Compared to native forests, pine forests had taller trees, lower shrub cover in the understorey, more and deeper exotic litter (other than pine), and were cooler and shadier. Reptile assemblages in pine forests were as rich as those in native forests, but pine assemblages were composed mainly of species that typically use closed-canopy rainforest and prefer cooler, shadier habitats. Burning did not appear to influence the assemblage structure of reptiles in native forest, but burning under pine was associated with increased skink abundance and species richness. Burned pine was not warmer or sunnier than unburned pine, a common driver of reptile abundance, so the shift in lizard use after burning may have been driven by structural differences in understorey vegetation, especially amounts of non-native litter, which were reduced by burning. Thus, burning for management under pine increased the abundance and richness of lizard assemblages using pine. Pine plantations do not support the snake diversity common to sclerophyllous native forests, but pine may have the potential to complement rainforest lizard diversity if appropriately managed. 相似文献
2.
我国桉树经营的技术问题与思考 总被引：4，自引：0，他引：4
桉树经营过程中出现的问题由来已久,这首先与我国社会经济发展水平较低有关,也与企业的经营理念不科学有关,和桉树本身的特性无关;虽然国内报纸、杂志、会议等多种形式对有关桉树经营问题的解释和分析,但对桉树的批评、误解、流言仍然较多,桉树的发展还处在风口浪尖。本文主要通过分析桉树在现实中所起的作用,尝试给桉树定位,以理清桉树的概念,解释桉树目前经营措施的来源;同时,通过分析桉树经营过程中存在的主要问题,特别是在林地清理和整地方面的问题,思考解决办法,协助人们正确认识桉树和桉树经营措施。 相似文献
3.
Zeqing Ma Henrik Hartmann Huimin Wang Qingkang Li Yidong Wang Shenggong Li 《European Journal of Forest Research》2014,133(2):307-321
Afforestation and ecological restoration have often been carried out with fast-growing exotic tree species because of their high apparent growth and yield. Moreover, fast-growing forest plantations have become an important component of mitigation measures to offset greenhouse gas emissions. However, information on the long-term performance of exotic and fast-growing species is often lacking especially with respect to their vulnerability to disturbance compared to native species. We compared carbon (C) storage and C accumulation rates in vegetation (above- and belowground) and soil in 21-year-old exotic slash pine (Pinus elliottii Engelm.) and native Masson pine (Pinus massoniana Lamb.) plantations, as well as their responses to a severe ice storm in 2008. Our results showed that mean C storage was 116.77 ± 7.49 t C ha?1 in slash pine plantation and 117.89 ± 8.27 t C ha?1 in Masson pine plantation. The aboveground C increased at a rate of 2.18 t C ha?1 year?1 in Masson pine and 2.23 t C ha?1 year?1 in slash pine plantation, and there was no significant difference in C storage accumulation between the two plantation types. However, we observed significant differences in ice storm damage with nearly 7.5 % of aboveground biomass loss in slash pine plantation compared with only 0.3 % loss in Masson pine plantation. Our findings indicated that the native pine species was more resistant to ice storm because of their adaptive biological traits (tree shape, crown structure, and leaf surface area). Overall, the native pine species might be a safer choice for both afforestation and ecological restoration in our study region. 相似文献
4.
Stand Density Control Diagrams for Scots pine and Austrian black pine plantations in Bulgaria 总被引：1，自引：0，他引：1
Stand Density Control Diagram (SDCD) is a stand-level mathematical model, which describes the relationships between yield,
density and mortality throughout all stages of stand development. The SDCD is primarily used to derive density control schedules
by management objectives. The main objectives of the present study are to define a modified model of SDCD for application
to Scots pine (Pinus sylvestris L.) and Austrian black pine (Pinus nigra Arn.) plantations in Bulgaria, to examine the fitness of the model with representative experimental data sets from plantations
of both species and to present a way of direct application of the SDCDs for practical purposes. The constructed SDCDs characterize
the spatial-temporal dynamics of the pine plantations in a broad range of densities, forest sites and growth stages from 4
to 26 (28) m of dominant height class. The full density lines were fixed with self-thinning exponents α = 1.69 and α = 1.75
for Scots pine and Austrian black pine, respectively, and the trajectories of natural thinning for 23 initial densities (444-40000/ha)
were determined. A direct way for application of the SDCDs to the plantation management was designed to estimate the optimal
initial densities for the maximum attainable final yield and large-size wood production by self-thinning stands. 相似文献
5.
Plantations cover a substantial amount of Earth's terrestrial surface and this area is expected to increase dramatically in the coming decades. Pinus plantations make up approximately 32% of the global plantation estate. They are primarily managed for wood production, but have some capacity to support native fauna. This capacity likely varies with plantation management. We examined changes in the richness and frequency of occurrence of bird species at 32 plots within a Pinus radiata plantation (a management unit comprising multiple Pinus stands) in south-eastern Australia. Plots were stratified by distance to native forest, stand age class and thinning regime. We also assessed the landscape context of each plot to determine relationships between bird assemblages and stand and landscape-level factors. Bird species richness was significantly higher at plots ≥300 m from native forest and in mature (∼20 years since planting) and old (∼27 years since planting) thinned pine stands. We were able to separate the often confounding effects of stand age and thinning regime by including old stands that had never been thinned. These stands had significantly fewer species than thinned stands suggesting thinning regime, not age is a key factor to improving the capacity of pine plantations to support native species (although an age × thinning interaction may influence this result). At the landscape level, species richness increased in pine stands when they were closer to native riparian vegetation. There were no significant differences in species composition across plots. Our study indicates the importance of stand thinning and retention of native riparian vegetation in improving the value of pine plantations for the conservation of native fauna. 相似文献
6.
论林木引种与森林可持续经营 总被引：6，自引：0，他引：6
森林是实现环境与发展相统一的关键和纽带,在实现国家可持续发展中具有不可替代的作用。外来树种是森林遗传资源的重要组成部分,具有一些乡土树种难以替代的优势。外来树种人工林可持续经营的核心问题是树种与种源的正确选择,为此,保存和丰富必要的基因资源就显得极为重要。外来树种具有一定程度的环境风险,但并没有人们想象的那样大。对当地生物多样性的影响有利有弊,关键是如何科学运作,包括确定合适的地域范围,与乡土树种的合理空间布局,以及如何使之在当地生态系统中形成密不可分的生物链。最危险的情况出现于因检疫不严而带来的病虫危害。 相似文献
7.
《Southern Forests》2013,75(4):285-291
Softwood forestry with non-native tree species is increasing worldwide and especially in many developing countries of the Southern Hemisphere. Tree plantations are beneficial in environmental and socioeconomic aspects, but at the same time there are recognised costs associated with afforestation. Our aim was to revise the existing information on the impact of exotic conifer plantations in north-western Patagonia on insect biodiversity. A total of five studies were selected and, in these, not every insect group responded in a similar manner to the habitat replacement. There was a tendency towards a reduction in abundance and species richness of several insects inside pine plantations. This change in abundance and richness was especially evident for ant assemblages and when pine plantations were dense. Beetle assemblages, in turn, showed diverse responses to the replacement of native vegetation with forests depending on the native habitat matrix. Our findings confirm that practices that reduce tree density (via thinning or during plantation) should be recommended to minimise their impact on insect biodiversity in north-western Patagonia. The consistent behaviour of ant assemblages, coupled with their abundance, ease to sample and unambiguous taxonomy make them reliable candidates for long-term monitoring of the impact conifer forestation in north-western Patagonia, as well as probably in other regions of the world in which non-native pines replace natural environments. 相似文献
8.
Frederick Cubbage Patricio Mac Donagh José Sawinski Júnior Rafael Rubilar Pablo Donoso Arnaldo Ferreira Vitor Hoeflich Virginia Morales Olmos Gustavo Ferreira Gustavo Balmelli Jacek Siry Mirta Noemi Báez José Alvarez 《New Forests》2007,33(3):237-255
Timber investment returns were estimated for the principal exotic and selected native species in the Southern Cone of Latin
America and in the Southern United States. Exotic eucalyptus plantations in South America were most profitable, with internal
rates of returns (IRRs) ranging from 13% to 23%, followed by exotic loblolly pine, with IRRs from 9% to 17%. Average loblolly
pine plantation returns in the US South were less profitable, with an IRR of about 9.5%, and natural forest management in
the South had IRRs of 4% to 8%. Subtropical native species plantations of the best araucaria and nothofagus species had reasonable
financial returns, with IRRs ranging from 5% to 13%. Subtropical or tropical native forests had fewer commercial timber species,
and had much lower growth rates and returns. Their IRRs were less than 4%, or even negative for unmanaged stands. State subsidy
payments for forest plantations or for timber stand improvements increased IRRs somewhat and reserving areas for environmental
protection reduced their IRRs slightly. Including land costs in the cash flows decreased these internal rates of return substantially.
Natural stand returns in Latin America were much less than those of plantations, but management of those stands offered better
rates of return than only holding the land. 相似文献
9.
《Southern Forests》2013,75(3):195-202
Pine plantations are thought to negatively impact species diversity and to irreversibly modify arid zones. However, some studies have suggested that through the application of appropriate management practices, the negative impacts of plantations may be reduced. Our aim was to study the effects of early pruning and thinning on the ground-dwelling insects found in pine tree plantations in Patagonia. We compared the abundance, species richness and composition of the beetle and ant assemblages within 16-year-old pine stands (n = 10) subjected to early pruning and thinning (i.e. before canopy closure) against a steppe habitat exposed to sheep grazing (‘control’, n = 10). To sample ground-dwelling insects, we deployed nine pitfall traps per plot (100 m2) for a 10-day period. Vegetation cover and plant species richness were significantly lower in the plantations than in the steppe. We found that beetle species richness was reduced in the managed plantations in comparison to the steppe but abundance was higher. In turn, species composition in the plantations was different from that of the controls. Ant species richness was similar among habitats but abundance was lower in the plantations. We conclude that, contrary to our expectations, management practices that lead to sparse plantations at early stages in the production cycle, do not offer a significant advantage in terms of reducing the impact of pines on ground-dwelling insects of Patagonia. 相似文献
10.
Soil properties under an exotic plantation (Pinus caribaea) and an indigenous plantation (Podocarpus imbricatus) were compared with adjacent secondary forests and abandoned land in the tropical forest areas of Jianfengling National Nature
Reserve in Hainan province, southern China. The surface soil (0–0.2 m) under Pi. caribaea has higher bulk density, lower soil organic carbon, total N, total K, available N, microbial biomass carbon, and smaller
soil microbial communities (as indicated by soil Biolog profiles) than under Po. imbricatus. Both land use types showed negative cumulative soil deterioration index (DI) compared to secondary forests. However, compared
to abandoned land (DI = –262), the soil quality of Po. imbricatus showed improvement (DI = –194) while that of Pi. caribaea showed deterioration (DI = –358). These results demonstrated that these exotic pine plantations can significantly and negatively
influence soil properties. By contrast, our results showed that adoption of indigenous species in plantations, or natural
regeneration, can improve soil quality. 相似文献
11.
Managing small remnants of native forest to increase biodiversity within plantation landscapes in the south west of Western Australia 总被引：1，自引：0，他引：1
Robert D. Archibald Michael D. Craig Katarzyna Bialkowski Chris Howe Treena I. Burgess Giles E.St.J. Hardy 《Forest Ecology and Management》2011,261(7):1254-1264
Recent expansion of industrial-scale plantations into agricultural areas in Australia has the potential to assist biodiversity conservation by rehabilitating ecosystems at the landscape scale and reducing edge effects, isolation and disturbance within remnants of native vegetation. However, the efficient management of remnants for biodiversity within a plantation estate requires knowledge of both the causes and the consequences of remnant degradation. With this in mind, we examined key ecosystem features and processes relating to soil chemistry, decomposition, native tree health and regeneration and vertebrate abundance, within small forest remnants (1-4 ha) embedded within Eucalyptus globulus plantations in south west Western Australia. Soil nutrient enrichment was significantly associated with a scale of vegetation modification in order from: (1) intact forest, (2) remnants with native understorey (UDN), (3) remnants with exotic understorey (UDE), (4) plantation and (5) pasture. We propose that, in this region, UDE remnants will often remain in a degraded state even after plantation establishment and the cessation of stock grazing. This is due, in part, to more rapid rates of nutrient turnover sustaining higher nutrient availability in the soil following the replacement of ligneous understorey plants with annual ones. Cotton strips placed in surface soils were often disintegrated in UDE remnants and largely intact in UDN remnants, indicating that decomposition was accelerated in the former. Continued tree decline and regeneration failure within UDE remnants will also reinforce the UDE condition. There was less canopy seed set and little or no seedling establishment in UDE remnants compared to UDN remnants. Therefore, management interventions to assist native tree regeneration in UDE remnants are needed. Fauna trapping highlighted the desirability of retaining, and preferably restoring, small remnants in plantations. Small native mammals were found exclusively in remnants and fewer introduced Mus musculus were present in UDN remnants. Higher numbers of native lizards were found in UDN remnants, but this result was not significant (marginally). 相似文献
12.
H. N. Le Houérou 《Agroforestry Systems》1992,18(2):107-148
Arid lands in the Mediterranean Basin harbour populations of saltbushes over substantial areas. These have been grazed for centuries and often cleared. There are also some 100,000 hectares of artificially established saltbushes, both native and exotic; they include no more than half a dozen species, when large scale plantations are concerned. Another dozen of exotic species, introduced from Australia, Southern and Northern America, have successfully undergone field trials and could be used on a large scale in a near future. The present paper attempts to review the current state of knowledge on Atriplex spp. in the Mediterranean Basin as a means of Arid Land rehabilitation at a time where huge areas in the region have undergone processes of severe degradation or have been subjected to desertization, particularly over the past four decades. In spite of a number of constraints in their establishment, management and utilization, the plantation of Atriplex spp. appears as one of the best way, if not the best one, to rehabilitate desertized areas and restore them to production, under the present state of knowledge on arid land rehabilitation. They, in particular, are amenable to inclusion into new, man-made agro-sylvo-pastoral systems of production well adapted to arid lands and to the needs of their populations. 相似文献
13.
Chisato Tomimura B. M. P. Singhakumara P. Mark S. Ashton 《Journal of Sustainable Forestry》2013,32(8):818-834
This study examined the vegetation growing beneath Caribbean pine (Pinus caribaea) plantations established within previously abandoned tea lands adjacent to intact rain forest in southwest Sri Lanka. To examine the pattern and composition of secondary succession and factors affecting it, vegetation was sampled in different relative locations (interior and edge conditions) within plantations. Results demonstrated that more vegetation was found near the plantation edges than in the interior, and this pattern was prominent for both wind- and bird- dispersed species. The vegetation represented a mixture of species belonging to a range of successional guilds representing early (17 species, 42.4% in stem count) and late-successional species (52 species, 40.6%), although native long-lived canopy tree species were mostly absent. Bird-dispersed species dominated the flora (80 species, 86.7% in stem count). Abundance of an exotic shrub Clidemia hirta (Melastomataceae) showed a negative correlation with that of other species, indicating its impact on native flora. Underplanting of native canopy species may be effective in assisting secondary succession and control C. hirta in the plantations. 相似文献
14.
Investigations were made in korean pine, mongolian scots pine and dahurian larch plantations in Laoshan Plantation Experiment
Station of Maoershan Experiment Forest Farm of Northeast Forestry University. Data are tabulated on the amount and seasonal
and annual fluctuations of fractional composition of the litter (conifer needles, branches, cones, bark scales, broad leaves)
in the three plantations. The accounts of conifer needle branch and bark scale litter are as follows: korean pine: 71.16%,
6.23% and 7.32%; mongolian scots pine: 43.65%, 18.52 % and 32.12%; dahurian larch: 90.30%, 7.83% and 1.85%. There are certain
broadleaf litter in dahurian larch and mongolian scots pine plantations (account for 7.61% and 8.92% respectively). The litter
wither and fall concent ratively in autumn in dahurian larch plantation and scattered all year long in korean pine and mongolian
scots pine plantations. Along with the increase of stand age, the absolute amount of litter tend to increase, the relative
amount of main fractional compositions (conifer needle, branch and bark scale) in korean pine and mongolian Scots pine plantations
maintain stead, whereas in dahurian larch plantation, the relative amount of conifer needle is decreased gradually and the
relative amount of other fractional compositions are increased gradually. 相似文献
15.
Radiata pine plantations in Chile 总被引：1，自引：0，他引：1
The landscape of the southcentral part of Chile is dominated by fast-growing plantations of radiata pine (Pinus radiata D. Don), and in lesser extent bluegum eucalyptus (Eucalyptus globulus Labill.), Italian poplar, and willows. Radiata pine was first introduced in 1885 as an ornamental species. During 1940–1960
it was used to control erosion in the Coastal Range. Finally, since the 1960s it has been used for commercial plantations.
The present extent of the plantation resource is 1,694,104 ha, of which 80.9 percent is radiata pine. During 1991, 1992, and
1993, this species was planted at rates of 75,416 ha, 81,868 ha, and 71,411 ha, respectively. Even though the soils are eroded
to different degrees, exhibit a variety of nutritional disorders, and contain some physical restrictions, the productivity
of radiata pine ranges from 18 m3/ha/yr to 35 m3/ha/yr. Additional stress comes from some potentially serious pests; for example, the European pine shoot moth, Rhyacionia buoliana, has presented a real threat to radiata pine. The main products obtained from radiata pine are exported to Japan, Korea,
Middle and Far East countries, and Europe. Sawlogs, sawntimber, pulpwood, clearwood, and wood chips are some of the products
comprising sales in 1994 of U.S.$1,564 billion.
The purpose of this paper is to show how radiata pine silviculture has changed since the last part of the 1980s in Chile.
Also we want to show how forestry activities have produced a profound and positive change in the social and economic environment
that surrounds the areas where the industry’s main production areas exist.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
16.
17.
Koreanpine(Pinuskoraiensis)(KP),mongolianscotspine(Pinussylvestrisvarmongolica)(MSP)anddahurianlarch(LarisgmeIinii)(DL)arethemainconiferousspeciesforforestationinnortheastregionofChina-LargeareplantationsofKP,MSPandDLhavebeenplantedintheregionsincel95o's.Whetherthestandstabilityandecolo-gicalequilibriumcanbemaintainedandtheforestfloorproductivitycanincreaseintheplantati0nsismainlydeterminedbytheamount,fracti0nalandchemicalcomp0sitionanddecomp0sitionrateof1itters,exceptforinfluenceofl0ca… 相似文献
18.
Despite the fact that tree plantations are not able to completely replace the ecological function of natural forests, the present study proposes to evaluate for which bird species or avian groups tree plantations act as habitat in fragmented landscape in southern Brazil. We compared the richness and abundance of bird species in a natural forest to adjacent plantations of Araucaria, a native tree species and of pine, an exotic plant in South America. Moreover, we evaluated the impact of tree plantations on richness of avian groups with different levels of dependence on forest habitat, feeding habits and foraging strata as well as on threatened species. The fixed 100 m radius point-counts method was used. A total of 114 bird species were recorded in all areas. Of those, 93 occurred in natural forest, 87 in Araucaria plantations and 81 in pine plantations. These results indicate that richness and abundance were lower in the pine plantations than in the natural forest and in the Araucaria plantations. Araucaria plantations can be used by a high number of bird species and their richness was not significantly lower than that observed in the adjacent natural forest. Our results suggest that Araucaria plantations could act as habitat for a large number of bird species, especially for forest-dependents species, insectivores, frugivores and species at different threat categories. 相似文献
19.
Monoculture plantations of Pinus, Eucalyptus and Acacia have beenestablished on rainforest lands throughout the world. However, this type of reforestation generally supplies low quality timber and contributes to landscape simplification. Alternatives to exotic monoculture plantations are now beginning to gain momentum with farmers and landholders attempting to establish a variety of rainforest trees in small plantations. When compared to the well studied commercial species, knowledge concerning the growth and management of many of these rainforest species is in its infancy. To help expand this limited knowledge base an experimental plantation of 16 rainforest tree species in a randomised design was established near Mt. Mee, in south-eastern Queensland, Australia. Changes in growth, form (based on stem straightness, branch size and branchiness), crown diameters and leaf area of each species were examined over 5 years. Patterns of height growth were also measured monthly for 31 months. Species in this trial could be separated into three groups based on their overall growth after 5 years and their growth patterns. Early successional status, low timber density, high maximum photosynthetic rates and large total leaf areas were generally correlated to rapid height growth. Several species (including Araucaria cunninghamii, Elaeocarpus grandis, Flindersia brayleyana, Grevillea robusta and Khaya nyasica) had above average form and growth, while all species in the trial had considerable potential to have increased productivity through tree selection. As canopy closure occurred at the site between years four and five, growth increments declined. To reduce stand competition a number of different thinning techniques could be employed. However, simple geometric or productivity based thinnings appear to be inappropriate management techniques for this mixed species stand as they would either remove many of the best performing trees or nearly half the species in the trial. Alternatively, a form based thinning would maintain the sites diversity, increase the average form of the plantation and provide some productivity benefits. 相似文献
20.
Gerelbaatar Sukhbaatar Batsaikhan Ganbaatar Tsogtbaatar Jamsran Battulga Purevragchaa Baatarbileg Nachin Alexander Gradel Tao Xu 《林业研究》2020,(1):13-26
Environmental factors play vital roles in successful plantation and cultivation of tree seedlings.This study focuses on problems associated with reforestation under extreme continental climatic conditions.The objectives were to assess relative seedling performance(survival and growth)with respect to plantation age,and to analyze the influence of specific climatic factors during the early stages of Scots pine(Pinus sylvestris L.)plantations.The study was carried out in reforested areas of the Tujyin Nars region of northern Mongolia on six Scots pine plantations ranging from 5 to 10 years.In each of the six plantations,five 900 m^2 permanent sample plots were established and survival rates and growth performance measured annually over 7 years.Results show high variation in survival among the plantations(p<0.001,F=29.7).Seedling survival in the first year corresponded directly to the number of dry days in May.However,survival rate appeared to stabilize after the second year.The insignificant variation of height categories throughout the observation period indicated low competition among individuals.Two linear mixed-effect models show that height and radial growth were best explained by relative air humidity,which we consider to be a reliable indicator of site-specific water availability.Insufficient amounts and uneven distribution of rainfall pose a major threat during the first year of plantation establishment.Humidity and water availability are decisive factors for a successful seedling plantation.This highlights the impact of drought on forest plantations in northern Mongolia and the importance of developing climate resilient reforestation strategies. 相似文献