共查询到20条相似文献,搜索用时 0 毫秒
1.
Smallholder tree plantation, now on the increase in Indonesia, has long been practiced by rural farmers as a strategy to optimize the expected utility of land, labor and other constraints. Increasing demand for timber has driven a shift toward commercialization of smallholder forestry. However, smallholders face huge challenges when they seek for commercial markets in the form of complex regulatory frameworks applied to smallholder plantations. This paper discusses the case of smallholder plantations in Gunungkidul District (Indonesia), considered one of the most commercialized timber marketing hubs for local, national and international markets. It analyzes how opportunities and challenges, resulted from different regulatory frameworks, affect the competitiveness of smallholder forestry practices. In this paper, regulatory frameworks are defined as not only regulations issued by public administrators at the domestic (local and national) level, but also cover the emerging market-based regulatory frameworks, i.e. voluntary certification of sustainable forestry and mandatory timber legality verification. 相似文献
2.
开展海南珍贵乡土树种坡垒、降香黄檀、秋枫套种南瓜、香蕉等农作物对林木保存率、生长情况及农作物产量影响的研究。结果表明:套种农作物可以显著提高坡垒、降香黄檀及秋枫的造林保存率,套种农作物3a后,3个树种的保存率均大于90%;而对照(没有套种农作物)的坡垒保存率仅为23%;套种农作物2a,坡垒、降香黄檀、秋枫的树高、胸径生长均与对照差异显著(p<0.05),其中以秋枫的生长最快,树高达3.83m、胸径达4.56cm,比对照分别提高了166.52%、228% 相似文献
3.
Using data from a household survey covering colonists and indigenous communities in the Ecuadorian Amazon, this paper analyzes the socioeconomic determinants of legal and illegal smallholder timber harvesting. The results of a multinomial probit model reveal that non-harvesting households are statistically likely to be poor, to receive nonfarm income, to have smaller areas in primary forest and to reside nearer population centers. Illegal logging is more likely to be carried out by poor households that do not have nonfarm income, have larger areas in forest and reside farther away from urban areas. Legal loggers, in contrast, are likely to come from wealthier households that have legal property rights to the land they possess or control but do not take part in nonfarm employment. Ethnicity has no effect on the likelihood of harvesting timber (either legally or illegally) and has only a marginally significant effect on non-harvesting households. The implications of these findings for policy are explored in the conclusions. 相似文献
4.
Over the past decades, the general trend towards shade reduction and intensification of cacao management has led to biodiversity losses. In the Peruvian Amazon, the regional government is heavily promoting crop conversion to shift from regionally marketed foods towards cacao (Theobroma cacao) and copoazu (Theobroma grandiflorum). While this shift is already visibly impacting the farming landscape and the lives of many smallholder farmers, little is known about the reasons that drive farmers to choose certain types of Theobroma species or cacao varieties over others. In this paper, we addressed how cacao farmers perceive and manage specific and varietal Theobroma diversity. We interviewed cacao farmers (n?=?20) during a seed-exchange fair and adapted a version of the four-square analysis to explore which Theobromas are currently adopted by farmers and why. The native cacao variety (cacao chuncho) was the one cultivated by most farmers, followed by the more industrial clonal varieties. The source of seeds and seedlings for the most cultivated varieties was a mix of donations by public institutions (for clonal varieties) and informal exchange among farmers (mainly for native and criollo varieties, and species i.e. macambo (Theobroma bicolor) and cacauillo (Theobroma speciosum)). The cacao varieties incentivized by public institutions were the least desired for future investment. The motivations for farmers to plant Theobromas was mainly based on the perceived current and potential market, but their desire to invest in a given species or variety was also based on pest resistance, traditional use, farm diversification and taste. Copoazu and CCN cacao varieties are produced by many households in large areas, while macambo, cacauillo and the cacao varieties TSH and porcelana are produced by few households in small areas. Our study suggests that agroforestry systems that include alternative Theobroma species are multi-strata and more diverse than cacao-based systems. It highlights the risks of agrobiodiversity loss associated with the promotion of industrial cacao varieties, and the importance of seed and seedling access for the development of diverse farming systems. We recommend the expansion of local seed-sharing networks and the extension of public cacao-donation campaigns to neglected and underutilized Theobromas with socio-economic and environmental benefits, in order to make the local farming systems more diverse and resilient. 相似文献
5.
Jari Celulose S. A. is a Brazilian-owned industrial enterprise located along the Jari River (the first major south-flowing
tributary of the Amazon). The company produces bleached kraft pulp for international and domestic sales. The raw material
of this pulp production comes from the 75,000 ha of intensively managed plantations of Pinus caribaea (Morelet) and Eucalyptus spp. harvested on 10- and 6-year rotations, respectively. All currently active Jari plantations were converted from primary
forest between 1968 and 1982. Silvicultural practices have been modified over successive rotations, including plantation species
changes, increased intensity of site preparation, fertilization, and chemical weed control. A review of data from the early
1970s to present indicates an increase in productivity over successive rotations and several plantation locations and soil
types. The reasons for this improvement are primarily related to the higher levels of silvicultural inputs and dramatic genetic
gains. The long-term sustainability of this productivity is discussed in terms of current and future inputs.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
Agroforestry Systems - In the original publication of the article, the article title was incorrectly published. 相似文献
7.
Current Indonesian beef production only meets 45% of local demand. Increasing local beef production through integration of cattle production in pre-existing oil palm plantations is a possible solution to meeting this shortfall. The oil palm understorey provides feed, alleviating the need to convert additional land to agriculture. Smallholders are important contributors to both Indonesian cattle and palm oil production. This case study research seeks to understand key aspects of smallholder cattle management in palm oil production areas, to highlight opportunities and barriers to cattle integration. Thirty-nine smallholder cattle farmers from four villages in South Kalimantan were individually interviewed. The lack of alternative feed sources was the major driver towards the adoption of cattle production using oil palm understorey as feed. Cattle grazing was uncontrolled due to labour shortages and occurred in individually owned and ‘plasma’ plantations, with cattle penned at night where possible to avoid theft. Arrangements on land access and use between stakeholders are needed for systematic cattle grazing and to control cattle theft. 相似文献
9.
Larch is one of the most important plantation species in the northeast region of China. After clear cutting of larch plantations it is the urgent problem to besolved that whether the second generation is continuously plant6d, whether the soil fertility is decreasing and the plantstion is how to be managed onthe forestry produCtion. In odder tO realize the secondgenerahon Of larch plantstions and to provide thetheoretical base and the reasonable managementmeasures, we inventoried the groWth o… 相似文献
10.
Fallow utilization schemes are becoming increasingly popular in agroforestry designs. However little attention has been given to the fate of valuable fallow plants after the end of the initial fallow cycle, and over successive fallow cycles on a regional or inter-fallow level. Evidence is presented here for the spontaneous long-term community enrichment of an area with valuable plants in a cyclic or iterative fashion, in the context of an existing fallow utilization scheme in the Amazon. Review of the ecological processes which operate at microsite, field and community levels indicate that:
a. |
Due to valuable plants left uncut in the swidden, seeds from valuable species are better able to survive the burn, and may experience a favored germination and establishment because of reduced competition, enhanced fertility of the young swidden, nutrient input from litterfall, and reduced soil temperatures and soil moisture evaporation.
| b. |
The much greater frequency of suitable germination and establishment sites in and around canopy gaps created by management practices during the fallow cycle interacts with a spatial and temporal distribution of fruit trees which may encourage a specific optimal foraging strategy among large numbers of frugivores. The net effect of this interaction would be to decrease competition for, and increase efficiency of, seed dispersal into the large number of available establishment sites.
| c. |
A greater opportunity for frugivore generated seed shadows exist in managed fallows due to the larger number of trails in and around these sites, which are used as flyways.
| d. |
A presence of the more efficient specialist fruit tree seed dispersal strategy in managed fallows — as opposed to the opportunist strategy — which produces patterns of seed dispersal more beneficial to the plant, and may have a longer more evenly spread fruiting season; which, along with relatively large numbers of trees would encourage frugivores to camp out on the resource, depositing seeds nearby.
| e. |
The existence of relict plant species that reflect pre-historic forest management which has led to long term and persistent effects on forest tree species composition.
| 相似文献
11.
Although the biological advantages in terms of animal production and improved soil fertility of the use of herbaceous legumes
have been well demonstrated in Kenya and elsewhere, adoption by small-scale farmers has often been disappointing. This has
led to increased research into the use of both indigenous and exotic fodder trees. In common with conventional pasture legumes,
tree fodders contain high levels of crude protein and minerals and many show high levels of digestibility. They are readily
accepted by livestock and presumably because of their deep-root systems, they continue to produce well into the dry season.
Antinutritive factors can be a problem, however, and polyphenolics, toxic amino acids, cyanogenic glycosides and alkaloids
are found in many tree species. There are abundant niches on small farms where fodder trees can be grown without affecting
crop production. Although detailed management recommendations are lacking, guidelines exist with regard to appropriate cutting
heights and harvesting frequencies. In the Embu region, it has been estimated that three kg of fresh fodder of Calliandra
calothyrsus has the same effect on milk production as one kg of commercial dairy meal. Up to about 500 trees (250 m of hedgerow)
will produce enough fodder to supplement one dairy cow for a complete lactation. The tree fodder can either replace the concentrate
without loss of yield, or it can complement it to produce more milk. It is being enthusiastically adopted by small-scale farmers,
many of whom are starting to produce their own seed. Other tree species are now being studied in order to avoid over-reliance
on a single fodder species.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
Plantations of exotic trees for industrial and agricultural purposes are burgeoning in the tropics, and some of them offer the opportunity to study community ecology of animals in a simplified forest setting. We examined bird community assembly in different aged groves of the industrial tree mangium ( Acacia mangium) at two plantations in Malaysian Borneo: Sabah Softwoods near Tawau, Sabah, and the Planted Forest Project, near Bintulu, Sarawak. Bird communities were compared among three age-groups of mangium (2-, 5-, and 7-years old) and logged native forest. Mangium rapidly developed into a secondary forest consisting of a wide diversity of understory trees and shrubs. The bird community correspondingly increased in species richness and diversity, and we were able to relate these increases specifically to canopy height, secondary canopy development, and shrub cover. Species of common, small bodied frugivores, nectarivores, and insectivores were diverse in older plantation groves, as were common mid-sized insectivores. However, large, specialized, and normally uncommon taxa (e.g., galliforms, pigeons, hornbills, barbets, midsized woodpeckers, muscicapine flycatchers, and wren babblers) were rare or nonexistent in the plantations. Because we lacked species-specific data on foraging, nesting, and other behaviors of most groups of birds, it was difficult to explain the precise causes of seral diversification in any group except woodpeckers, which have been well studied in Southeast Asia. Thus, in future, particular emphasis needs to be placed on obtaining such data. Industrial plantations, by virtue of their simple structure, variably aged groves, and bird community richness, are good places to gather such data. 相似文献
13.
As part of an assessment of sustainability for the strip clear-cutting system (or Palcazú Forest Management System), we determined whether commercial tree species regenerating in two strips (30 m × 150 m) clear-cut in the Peruvian Amazon in 1989 would reach commercial size (≥30 cm diameter at breast height (dbh)) 40 years after the initial cutting, the expected harvesting cycle. We projected the growth of six common commercial species ( Eschweilera bracteosa, Guarea cinnamomea, Micropholis guyanensis, Pouteria guianensis, Qualea paraensis, and Cedrelinga catenaeformis) and two pioneer species ( Alchornea triplinervia and Miconia phaeophylla) using bootstrapping techniques (the Lieberman model), based on 2-year diameter increments (2004–2006) and mortality rates obtained from 1630 trees growing in secondary forest sites including the regenerating strips. These demographic data were further used to project the growth of all trees ≥6.5 cm dbh of commercial (sawnwood value) species from each strip, and from a deferment-cut treatment applied to half of one of the strips. Three models were used for growth projections: (1) using all diameter increments to simulate average growing conditions, (2) using diameter increments of trees exposed to high light to simulate growing conditions under intensive forest management with low mortality rates and (3) using diameter increments of the fastest growing individuals. Roundwood volume was calculated using allometric equations for emergent, canopy, and subcanopy species. 相似文献
14.
The rapid increase in rubber monoculture in Xishuangbanna has resulted in extensive damage to its local ecosystem. To decrease the negative effects, the concept of the ecological-economic rubber plantation (EERP) system was proposed. The EERP entails intercropping rubber plants with other economically significant plants, which would not only decrease the ecological impact of the rubber plantation, but also maintain and potentially increase its profitability compared with rubber monocultures. In order to select the appropriate species and intercropping pattern in the EERP system, we compared the photosynthetic parameters of five economically important trees (Swietenia mahagoni, Coffea arabica, Mesua ferrea, Myristica yunnanensis and Paramichelia baillonii) under four irradiance levels. The optimal irradiance intensity of C. arabica and M. yunnanensis was approximately 40%, and these species can be planted in the understory of an 8- to 15-year-old rubber forest. Adult S. mahagoni, M. ferrea and P. baillonii grow taller than the rubber trees, and their seedlings also show superior performance in 100% irradiance than in other irradiances. Thus, in an EERP, these valuable trees could be planted adjacent to rubber plantations but on sites that are economically and environmentally marginal for rubber production. 相似文献
15.
We investigated the sapling leaf display in the shade among trees of various leaf lifespans co-occurring under the canopy
of a warm-temperate conifer plantation. We measured leaf-area ratio (aLAR) and morphological traits of saplings of evergreen
broadleaved tree species and a deciduous tree species. Although we found large interspecific and intraspecific differences
in aLAR even among saplings of similar size in the homogeneous light environment, we did not find a consistent trend in aLAR
with leaf lifespan among the species. While deciduous trees annually produced a large leaf area, some evergreen broadleaved
trees retained their leaves across years and had aLAR values as high as those of deciduous trees. Among leaf-level, shoot-level,
and individual-level morphological traits, aLAR was positively correlated with current-year shoots mass per aboveground biomass
in deciduous trees, and with the area of old leaves per aboveground mass in evergreen broadleaved trees. Thus, tree-to-tree
variation in the degrees of annual shoot production and the accumulation of old leaves were responsible for the interspecific
and intraspecific variations in aLAR. 相似文献
16.
Survey data have been collected from four rural communities in Leyte Province, the Philippines, on household tree planting
and management intentions, as well as the socio-economic characteristics, attitudes to tree planting and management, farming
practices and the number of trees planted. In relation to intended tree planting and management activities, respondents were
asked a series of structured questions as to what tree species they intend to plant, how many individual trees of each of
those species they plan to plant, and for what purpose they propose to plant each of the tree species. This paper reports
the results of analyses of the stated tree management intentions of households in the four communities and identifies the
socioeconomic factors that influence householders’ tree management intentions. Respondents were generally enthusiastic about
the possibility for further tree planting on their land, 75% indicating they would undertake planting. About 60% indicated
an interest in commercial tree farming, with no significant differences in this level of interest between communities. It
was found that a number of socio-economic variables indicating higher levels of land ownership and previous experience in
the forestry industry are related to the intention to plant trees to produce timber for sale. These include the use of materials
from public lands, participation in community organisations and community forestry programs, and the present management of
trees to produce timber for sale. 相似文献
17.
Although many reforestation projects have attempted to mitigate deforestation in the Philippines, most have focused on planting introduced trees, often with low success rates. A smallholder-based project in the Visayas region planted native species instead. This study assessed the growth performance of forty-four native and sixteen introduced species in 25 sites established by this project between 1995 and 2000. Diameter at breast height and total height were measured for 2,789 trees. Mean annual increments for diameter (MAID) at breast height and height (MAIH) were significantly higher for trees planted on limestone-influenced soils (MAID = 1.19 cm/year; MAIH = 1.05 m/year) than on purely volcanic soils (MAID = 0.81 cm/year; MAIH = 0.78 m/year). Growth of two native species, Melia dubia and Terminalia microcarpa, was higher than that of the widely planted exotic Swietenia macrophylla. The height increment for the highest-performing dipterocarp species, Shorea guiso, Shorea contorta, and Parashorea malaanonan, was not statistically different from the MAIH of S. macrophylla. A range of soil characteristics predicted performance, with organic matter predicting growth for six species, and percent nitrogen and percent clay predicting performance of five species. These findings show that certain native species can perform better than some exotic species when planted in open areas. They also disprove the widely held belief in the Philippines that Dipterocarpaceae cannot be planted in grasslands, and suggest that dipterocarps can be used successfully in reforestation. Finally, the findings show that more research is needed on species-site matching and on silvicultural management of native species plantations. 相似文献
18.
根据联合国粮农组织2001年发布的全球森林资源统计资料,全球人工林(Plantedforest)的面积是1.87亿hm2,比1995年的1.24亿hm2有较大增加。亚洲占总面积的62%,其中中国(占24%)和印度(占18%)拥有量最大。全球每年造林约450万hm2,亚洲和南美洲占91%。造林树种以松树(占20%)和桉树(占 相似文献
19.
To better manage wildfires and plantations in Kurdistan, native tree species commonly used in planting and reviving forests such as Quercus brantii Lindl., Q. infectoria Olivier, Q. libani Olivier, Pistachio atlantica Desf., Fraxinus rotundifolia Vahl, and Robinia pseudoacacia L. were evaluated and compared in terms of fire sensitivity and fire resistance. To determine fire sensitivity, indices such as the fl ammability index, ignition time, fl ame durability, moisture content, carbonized surface, mass reduction, bulk density, as well as dry weight of wood, bark, and leaves were used. The data were subjected to ANOVA. The means obtained, after examining homogeneity or heterogeneity of the variances, were compared using parametric and nonparametric comparison tests. There was a significant difference at the level of 5%. Based on the analysis of these indices, the species could be divided into three groups: species sensitive to fire such as Robinia pseudoacacia, species moderately sensitive to fire such as F. rotundifolia, and species relatively resistant to fire, including Q. brantii, Q. libani, Q. infectoria, and P. atlantica. 相似文献
20.
In the Philippines, timber production on small farms has become profitable as a result of reduced supplies due to extensive
deforestation and increasing demand. In the early 1990s, when the price of timber was high, farmers were promised huge returns
from tree farming. However, widespread planting of few species has led to oversupply and a sharp decline in the price of farm-grown
timber. Moreover, low intercrop yields as a result of competition from fast-growing trees and low timber yields due to poor
tree management, further reduce net economic returns. In spite of this, interest in tree farming remains high. This paper
examines the private profitability of two tree-maize systems, namely trees in blocks and trees in hedgerows, compared with the alternative of maize monocropping. The analysis reveals that maize monocropping provides higher returns
to land at the current timber price, but considerably lower returns to labour, than the maize-tree systems tested. This suggests
that tree farming is a more attractive option for labour and capital-constrained households or those with off-farm opportunities
that compete for their labour. These farmers may raise productivity and income by planting trees on the excess land that cannot
be devoted to annual crops. The analysis also indicates that wide-spaced tree hedgerows are superior to tree blocks, due to
lower establishment and management costs, longer periods of viable intercropping and more rapid tree growth. 相似文献
|