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1.
Industrial forest plantations are both hailed and vilified for their socio-economic effects on local communities. As such, we posed the following questions: (1) what opportunities do industrial forest plantations bring to local communities? and (2) what benefits are lost with the establishment of industrial forest plantations?Households neighboring industrial forest plantations in five villages of mid-western Uganda were surveyed. A large majority of the respondents (92.6%) stated that they had benefited from forest plantations, while a minority (7.4%) stated they did not. Fuelwood and employment were the most mentioned benefits. Approximately 47.9% of respondents stated that they had lost certain benefits due to the establishment of industrial forest plantations, while 52.1% stated they lost no benefits. Occupation, the number of people in a household and the length of residence in the area influenced responses on whether participants had lost certain benefits.Access to land was the most mentioned (82.2%) benefit lost due to industrial forest plantations. The study supports the notion that industrial forest plantations can provide certain benefits in the initial years of establishment but may also deny local communities historically established customary access and user land rights. Local livelihoods should be integrated into forest plantations management plans. 相似文献
2.
KarolyREDEI 《林业研究》2002,13(4):260-264
匈牙利刺槐（（Robinia pseudoacacia L.)是在17世纪初从北美引入到欧洲的第个森林树种。在匈牙利，刺槐是非常重要的速生树种，为经济和生态目的，可以成功营造刺槐人工林。结合该树种的生长特点选择营林措施，可以最大限度的提高刺槐人工林的成活率和生产力。本文根据林分结构和森林产量长期实验林的研究成果，提出了刺槐林的抚育作业次序。制定好的营林计划和模式将会培育出效益刺槐林，并能使土地经营者更好地接受该树种。同时，刺槐也是一个非常有用的能源生产树种，本文展示了对这方面的研究成果。图2表1参8。 相似文献
3.
Determining the optimal rotation period was a crucial component of forest sustainable management strategies, especially under climate change. This paper had two objectives: (1) to determine the economic benefits and optimal rotation periods for timber production when coupled to carbon sequestration, as predicted by time series prediction models for Pinus tabulaeformis plantations in China; and (2) to evaluate how different carbon prices and interest rates affected optimal rotation periods using the forest land expectation value. The results suggested that time series prediction models were valuable for estimating timber volumes and carbon sequestrations based on surveys of different-aged stands. Importantly, since integrating carbon sequestrations into timber production benefits did not increase optimal rotation periods, this should promote P. tabulaeformis plantation management. In the sensitivity analysis, a higher carbon price increased the profitability of carbon sequestration and timber production, but not optimal rotation periods, though they were reduced under higher interest rates. In conclusion, incorporating both timber production and carbon sequestration benefits would sharply increase forest-based revenues, while realizing the carbon sequestration potential of P. tabulaeformis plantations. This approach was clearly useful to the development of reforestation/afforestation projects trying to mitigate climate change and also provided a theoretical basis for sustainable forest management. 相似文献
4.
In southern Aragua state, Venezuela—an area regarded as high priority for local and national development—important sources
of income and traditions are related to a history of manufacturing wood products including furniture and woodcraft made of
the native tree species Samanea saman. However, scarcity of wood has recently become a major constraint for people of Magdaleno, putting at risk traditional knowledge
and employment opportunities. Based on an integrated approach taking into account biophysical, ecological, social and technological
issues, a broad group of potential tree species were assessed in a landscape-scale analysis to promote a plantation project.
Analysis of policy implications is made in the context of national legislation, socio-economic, institutional and environmental
issues. The role of research and communication to improve decision-making processes at all scales are also examined. At least
three wood species (Samanea saman, Acacia mangium and Gmelina arborea) with a total of 37 sites and an aggregate area of approximately 26,600 ha (266 km2), were found to be potentially able to sustain a local development initiative for all five municipalities located in southern
Aragua state. In terms of implementation, small-scale forestry (SSF) is viewed as a new policy shift for forest management
according to the new national forest legislation where local development is a central element. SSF faces several constraints
and faces a wide variety of political issues. Critical among these issues are: (a) how SSF approaches deal with legislation
and land tenure regulations; (b) the creation of community-based forest enterprises based on simplified management plans,
(c) a broad assessment of potential ecosystem services delivered by forest plantations; and (d) improving communication of
research for decision-making. Decentralization and institutional strengthening are identified as two basic conditions for
pursuing sustainable management. 相似文献
5.
Sheauchi Cheng Yukio Hiwatashi Hideki Imai Mitsuru Naito Tatsuka Numata 《Journal of Forest Research》1998,3(4):199-204
The major causes of deforestation and degradation of natural resources in the Belete-Gera Forest of Ethiopia are coffee production
activities and encroachment into forestland to expand farmland and pasture. Population growth, and the government’s land-reform
and re-settlement programs have caused local residents to lose harmony with the land. Forest management in this area hasn’t
yet been fully developed. The objectives of this study are to identify the extent of deforestation and natural resource degradation,
in preparation for a sound management plan. Encroachment of farmland and pasture into natural forest during the past four
years has been identified through interviews and aerial photo interpretation. The encroachment rate is 1.45% per year. Encroachment
occurred mostly on areas with gentle slopes adjacent to populated villages and along roads and footpaths. The extent and impact
of coffee production activities were examined through agency documents, forest survey data and vegetation survey. It is estimated
that up to 49% of the accessible natural forest is under the influence of coffee production activities, among which collecting
of naturally grown coffee beans has the least and the coffee plantations has the most impact on the natural forest. Coffee
plantations in natural forest have reduced the forest density and species diversity. Age structure of the trees is limited
to mature and old classes only, which eventually endangers their function as shade for coffee plantations.
This project was funded by the Japan International Cooperation Agency. 相似文献
6.
《Forest Ecology and Management》2007,238(1-3):375-383
Increasingly, regional conservation plans are using information about how animals respond to changes in habitat characteristics to provide guidelines for management. However, the ability of these plans to effectively guide management remains largely untested. To test a regional bird conservation plan developed by Partners in Flight, we compared bird abundance in untreated stands to that of stands where shrub cover had been reduced to lower the risk of fire. We used these data to evaluate whether birds identified as focal species in the conservation plan increased or decreased in abundance as a result of the treatments. Over a two-year period, two of 12 Partners in Flight oak woodland and chaparral focal species were more abundant at treated units in both years; no species were consistently less abundant at treated units in both years. These results suggest small-scale (7–42 ha) treatments are consistent with the objectives identified in the Partners in Flight regional conservation plan because they benefited species associated with edges, but did not have negative effects on shrub-associated species. We suggest that this is a result of the small size of treatments and the retention of shrub patches in treated areas. An alternative explanation is that the bird/habitat relationships used to develop the conservation plans do not apply in this study area. We tested this hypothesis by comparing the correlations between habitat characteristics and bird abundance with the information in the conservation plans. In all but one case, the direction of the correlation agreed with information in the conservation plan. This project illustrates that even though the ability of conservation plans to predict the ecological effects of management activities may be limited, they can play an important role in interpreting the results of ecological monitoring. 相似文献
7.
Anders Ræbild Hanne H. Hansen Joachim Dartell J.-M. Kiléa Ky Lassina Sanou 《Agroforestry Systems》2007,70(2):157-167
Woody vegetation in cultivated landscapes in Burkina Faso is influenced by agricultural activities that are in turn influenced
by institutional arrangements. Research was undertaken in a village in south-west Burkina Faso to investigate the relationship
between species composition, diversity, density, species accumulation and land use category. Additionally the relationship
between number of trees, size of farmed land and farmer ethnicity was investigated. Indigenous Tiéfo farmers had on average
more than double the number of large (>4 m) trees of Vitellaria paradoxa Gaertn. f., Parkia biglobosa (Jacq.) R. Br. Ex G. Don and Anacardium occidentale L. than farmers belonging to other ethnic groups, but this was partly explained by a larger area being available. Differences
between ethnic groups were not significant when expressed per ha. Botanical inventories of fallows more than 4 years old,
cultivated parklands and plantations of Mangifera indica L. and A. occidentale showed that tree density and Simpson’s index of diversity for trees were highest in the fallow. Simpson’s index was not significantly
different for regeneration, but sample-based species accumulation curves indicated that species accumulation in parklands
was faster than in plantations when expressed per individual. The average regeneration density was 12,605, 1,995 and 6,772
seedlings ha-1 for fallow, parklands and plantations, respectively. This low density for parklands means that species accumulation is slow
compared to the other land uses when expressed per unit area. Fallow seems the most efficient way of keeping tree diversity
in the agricultural landscape. 相似文献
8.
《Journal of Sustainable Forestry》2013,32(2-3):109-121
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
9.
In the last 10 years, four species of psyllid were detected in Brazil on eucalypts: Ctenarytaina spatulata in 1994, Blastopsylla occidentalis in 1997, Ctenarytaina eucalypti in 1998 and Glycaspis brimblecombei in 2003. The latter two are serious pests in several countries. In Brazil, G. brimblecombei caused significant damage to the eucalypt plantations in the first years of its introduction. Now this pest is under control
due to the programmes of integrated pest management, where the parasitoid is the principal control agent. The four eucalypt
psyllid species introduced into Brazil are presented with information on distribution, hosts, biology and control. 相似文献
10.
This article investigates options for reforestation in degraded forests in Central Vietnam within the context of sustainable forestry and presents a forest management plan for the forests around the community of Phong My. In the past, the area was damaged during the war between Vietnam and the United States and after that by overcutting. Forests have gradually been degraded and now they are replaced by plantations of fast-growing Acacia (Acacia mangium). After final harvests, the stand remnants are burnt and the burnt area is again regenerated via artificial regeneration of Acacia. Here, we propose several mixtures in which Acacia stands can be augmented with other tree species. A proposed system of afforestation and subsequent management is given here with the goal of encouraging mixed species, multiple cohort stands, and disincentivizing the method of slash-and-burn. The proposed afforestation patterns were also used to calculate the future number of seedlings required to enable the enlargement of quality forests at the expense of degraded ones. 相似文献
11.
C. Pascual A. García-Abril L.G. García-Montero S. Martín-Fernndez W.B. Cohen 《Forest Ecology and Management》2008,255(11):3677-3685
In this paper, we present a two-stage approach for characterizing the structure of Pinus sylvestris L. stands in forests of central Spain. The first stage was to delimit forest stands using eCognition and a digital canopy height model (DCHM) derived from lidar data. The polygons were then clustered (k-means algorithm) into forest structure types based on the DCHM data within forest stands. Hypsographs of each polygon and field data validated the separability of structure types. In the study area, 112 polygons of Pinus sylvestris were segmented and classified into five forest structure types, ranging from high dense forest canopy (850 trees ha−1 and Loreýs height of 17.4 m) to scarce tree coverage (60 tree ha−1 and Loreýs height of 9.7 m). Our results indicate that the best variables for the definition and characterization of forest structure in these forests are the median and standard deviation (S.D.), both derived from lidar data. In these forest types, lidar median height and standard deviation (S.D.) varied from 15.8 m (S.D. of 5.6 m) to 2.6 m (S.D. of 4.5 m). The present approach could have an operational application in the inventory procedure and forest management plans. 相似文献
12.
In this study, we identified the distribution characteristics of a mixed forest of coniferous and broad-leaved trees (a typical forest type in Hokkaido, Japan) using landscape metrics and topographic factors, and attempted to apply this knowledge to examine forest management. This approach provides a new perspective (i.e., the landscape structure) on forest management, which traditionally has been determined on the basis of individual forest stands. We first created a cover type map of the study area by means of aerial photo interpretation. The characteristics of each cover type identified from the photographs were determined using landscape metrics for each cover class. We digitized a forest administrative map (1:20,000 scale) using 20-m contours, and imported this into GIS software to produce a terrain model; on this model, we overlaid the cover types. Our examination of landscape metrics showed that most of the natural forest could be managed similarly. However, our examination of topographic characteristics revealed exceptions (e.g., areas that are difficult to regenerate) that will require particular attention when managing the natural forest. Based on the information we obtained, we proposed a guideline for sustainable forest management. From the land cover map, we proposed an “improved” cover type map to illustrate the development of a high growing stock of forest based on forest management. We compared the current cover map with the “improved” cover map and demonstrated that the improved form would have more significant effects on fauna that do not recognize differences in the proportion of the dominant species types than on those that can recognize these differences. Our results show how the information obtained using landscape metrics and terrain models is an essential tool for various stages of forest management planning. 相似文献
13.
澳大利亚国土面积为768万km2,林地面积占国土面积的13.8%。森林主要分布在东南沿海一窄长地区。该国经营林业的战略是:以发挥森林的生态环境利用为主。澳国将全国林地面积的77%划为环保林,其中501万ha划为森林保护区和国家森林公园。天然成熟林实行凭证定量采伐。与此同时,大力发展速生优质人工林。其主要树种为辐射松和南洋杉,并以此代替低产的桉树林。目前占林地总面积2%的人工林,其采伐量已占全国采伐量的40%。在经营强度上,人工林大于天然林。扩大林业经济效益的主要途径是发展纸浆和造纸工业。澳大利亚把在一定时期内保持林产品进口,作为保存、发展本国森林资源的保护战略。 相似文献
14.
Acacia mangium is a very fast growing species belonging to the family Leguminosae that has been introduced in the plantations in Bangladesh for its faster growth and wide range of adaptability. The present study aimed at development of growth and yield prediction models for the species using simultaneous equation method. Models were selected for the species to estimate stand dominant height, stand diameter, stand basal area per hectare and total volume yield per hectare. Paired t-test, 45-degree line test, percent absolute deviation and biological principle of stand development were used for the validation of chosen models. The results suggest that the models derived were statistically and biologically acceptable and could be satisfactorily used for stands of Acacia mangium of ages 4–7 yrs based on a base age of 6 yr. 相似文献
15.
《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
16.
Herbicides and mechanical control of Imperata cylindrica as a first step in grassland rehabilitation
P. J. Terry G. Adjers I. O. Akobundu A. U. Anoka M. E. Drilling S. Tjitrosemito M. Utomo 《Agroforestry Systems》1996,36(1-3):151-179
This review is prefaced by an introduction to biological characteristics of Imperata cylindrica which relate to its control by chemical and mechanical methods. Of the many herbicides tested and used against I. cylindrica, glyphosate has became the market leader but the potential of imazapyr is also recognized. The activity of additives to improve glyphosate and imazapyr performance is summarised and linked to a review of spray volume rates and the use of three types of application equipment: hydraulic (knapsack) sprayers, spinning discs and weed wipers. An example of the practical use of glyphosate in an estate crop is given. The role of tillage in the management of I. cylindrica is discussed but emphasis is given to pressing as a technique for promoting natural regeneration of forestry species. An integrated approach is considered to be essential for the management of I. cylindrica whereby fire prevention and methods of control are deployed in the conversion of Imperata-dominated land into sustainable, productive systems. Examples are given of integrated management in commodity plantations, rehabilitation of Imperata grasslands through reforestation, and conservation tillage to sustain soil fertility and productivity. 相似文献
17.
An integrated tree plantation approach combining indigenous livelihoods and industrial wood production is being implemented in West Kalimantan, Indonesia. In this study the economics of land-use was investigated in villages within the plantation scheme. The effect of three alternative land-use scenarios and costs and benefits of each land-use type were studied using linear programming. The scenarios were based 1) on the current land-use, 2) on the integrated tree plantation system with incentives and government regulations, and 3) on a financially optimal land-use distribution. Additionally, plant species richness in different land-use types was surveyed. The scenarios had different kinds of effects on villages varying in respect to their possibilities for land-use intensification. In villages with extensive land use, establishment of tree plantations without any land-use regulations increased the potential economic return on land, resulting in conversion of natural and man-made semi-natural forests into swidden fields. In villages with more sedentary agriculture, the plantation scheme did not create pressures towards remaining forests even in the case of financially optimal land-use distribution. Incorporation of land-use regulations prevented further deforestation but also decreased households' economic returns. The results also showed that conversion of Imperata grasslands to any other land-use increased species richness. Incentives, restrictions or regulations aiming at conserving natural and semi-natural forests are needed to ensure conservation of biodiversity and long-term improvements in local livelihoods. It can be concluded that tree plantations can be combined with other land-use practices: They can improve the economic return on land without further degradation of the environment.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
18.
Reforestation is one of the most important and efficient measures of water and soil conservation. Based on field investigations
in the Shangyang Soil Conservation and Reforestation Station in Huizhou, Guangdong Province, China, we studied the variation
in vegetation development, vegetation succession processes and soil erosion. The regional vegetation consists mainly of monsoon
evergreen broad-leaved forests (MEBF). The area was deforested and became a denuded hill area with extremely high soil erosion
in the 1960s and 1970s. Then, the area was closed in order to allow recovery of the vegetation. Under natural conditions the
vegetation development and succession processes were slow during which soil erosion and strong sunshine and evaporation slowed
down the development of the vegetation. About 25 years later, the vegetation cover was still merely 35% or so. The dominant
vegetation types were heliophilous herbage and shrubs which formed a poorly developed shrub-herbage community and erosion
remained high. In contrast, reforestation with selected tree species dramatically speeded up the vegetation succession process.
About 12 years after reforestation, vegetation cover of the Acacia auriculiformis plantations in the Shangyang Station was 90% and erosion was under control. After 23 years, understory vegetation, consisting
of indigenous species, had developed in the plantations. The planted trees and naturally developing herbage, shrubs, bamboo,
local trees and liana formed a complex vegetation community in three layers. It will take 60 years for the vegetation to succeed
from bare land to a secondary growth forest under natural conditions. Reforestation may speed up the vegetation succession
process. The time may be reduced to 20 years. Reforestation is the most effective measure of vegetation restoration and erosion
control in this area.
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Translated from Acta Ecologica Sinica, 2006, 26(8): 2558–2565 [译自: 生态学报] 相似文献
19.
利用EM50土壤水分监测仪,在样地尺度上,测定了祁连山青海云杉天然林、无间伐和间伐强度为20%的人工林地生长季节的土壤水分,对比分析间伐对人工林土壤水分的影响。结果表明:未间伐人工林林地表层(10 cm)土壤含水量显著高于间伐强度为20%的人工林和天然林,间伐导致了人工林林地表层土壤水分下降;而对于深层土壤含水量而言,间伐措施又显著提高了深层60 cm处的土壤含水量。与天然林地土壤含水量相比,无间伐人工林深层60 cm和80 cm处的土壤体积含水量仅为天然林的49.7%和52.1%,深层土壤已经出现旱化现象,间伐措施能够减缓这种旱化现象。 相似文献
20.
Reforestation is one of the most effective ways to reduce the impacts of desertification. Caragana microphylla Lam. and Pinus sylvestris var. mongolica Litrin have been widely used to stabilize shifting sands in the Horqin sandy land area since the 1980s. However, soil water
depletion has been of major concern in C. microphylla and P. ongolica plantations and in many places current soil moisture cannot meet the demand of growing plants. To determine the water budget
of C. microphylla and P. mongolica plantations, we studied the effect of plantations on soil moisture and assessed the evapotranspiration in plantations of
both species. Investigations were conducted at a fenced plot at Wulanaodu (42°29′N, 119°30′E, 479 m a. s. l), located at the
western edge of the Horqin Sandy Land area in Inner Mongolia, northern China. Five year old C. microphylla and seven year old P. mongolica plants were selected from the plantations and transplanted to iron boxes (400 cm×200 cm×120 cm) which can drain extra water.
Plant spacing of 1 m×1 m was applied to P. mongolica, and two plant spacings of 1 m×1 m and 1 m×2 m to C. microphylla. The transplanted plants grew for two years in the boxes. Soil moisture from soil surface to a depth 80 cm were measured
at 20 cm intervals in boxes every 10 d (2004) or 3 d (2005) during the growing season with a TDR water meter. The evapotranspiration
was estimated from a mathematical formula and the characteristics of soil water consumption and evapotranspiration of these
two plantations were analyzed. The soil water of P. mongolica was more than that of C. microphylla at the same 1 m×1m spacing. The soil water of C. microphylla with the 1 m×2 m spacing was more than that of the 1 m×1 m spacing. The evapotranspiration ranged from high to low as follows:
C. microphylla (1 m×1 m), C. microphylla (1 m×2 m) and P. mongolica (1 m×1 m) during the growing seasons. The evapotranspiration of individual plants ranging from high to low was C. microphylla (1 m×2 m), C. microphylla (1 m×1 m), and P. mongolica (1 m×1 m) during the growing season. C. microphylla grown for five year consumed more water than P. mongolica grown for seven years at the same spacing.
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Translated from Acta Ecological Sinica, 2008, 28(5): 1981–1990 [译自: 生态学报] 相似文献