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1.
Litterfall, which is influenced by physical and biological factors, is a major pathway for carbon and nutrient cycling in forest ecosystems. The purpose of this study was to investigate monthly litterfall production in three forests in Jeju Island differentiated by forest composition and precipitation: Cheongsu(Quercus glauca as the dominant species;low precipitation), Seonheulb(Q. glauca as the dominant species;high precipitation), and Seonheulm(Q. glauca and Pinus thunbergii as the dominant species;high precipitation). Litterfall was collected monthly from April to December 2015 and divided into leaf litter, twig, bark, seeds, and unidentified materials.Seasonal patterns of litterfall production varied across stands according to their species composition. However,the amount of leaf litterfall and total litterfall were comparable among stands, ranging from 362 to 375 g m-2 for leaf litter and 524 g m-2 to 580 g m-2 for total litterfall.Oak leaf litter in May was the highest in all stands, while needle litter was the highest in December in Seonheulm.High twig litterfall in July may be attributable to high rainfall with strong winds and storms during the rainy season. Although forest type and climate factor had no influence on litterfall amounts in this study, the pattern of litterfall production was species dependent, suggesting diverse effects on carbon and nutrient cycling in these forests.  相似文献   

2.
The physical properties of soil on two hill slopes of 35% and 55% in orange orchard cultivated by the Mro tribe of Chittagong Hill Tracts （CHTs） were evaluated and compared with those of bushy hill forests. Soil samples were collected from three different depths （0-5 cm, 5-15 cm and 15-30 cm）, digging three profiles in each land use for determining moisture content, organic matter content and particle density. Maximum water holding capacity, field capacity, dry and moist bulk density and porosity were determined only for the surface soils. Moisture content at all the soil depths was significantly higher （p≤ 0.05） in orange orchard than in forest on both the slopes. Orange orchard contained lower mean soil organic matter than forest on 55% slope, while it contained higher values on 35% slope compared to forest. The highest value of the above two properties was found at surface soil in both the land uses on both the slopes, decreasing with the increase of soil depth. On both the slopes maximum water holding capacity and porosity of surface soil and particle density at all soil depths were lower in orange orchard compared to those in forest. Field capacity values of surface soil did not show consistency in trend for the differences between the two land uses on both the slopes. Bulk density value of moist and dry surface soil was higher in orange orchard than in forest on both the hill slopes.  相似文献   

3.
A study was conducted to identify the differences in the decompositions of leaf litter, lignin and carbohydrate between coniferous forest and broadleaf forest at 20℃ and 30℃ in Huangshan Mountain, Anhui Province, China. Results showed that at 20℃ mass loss of leaf litter driven by microbial decomposers was higher in broadleaf forest than that in coniferous forest, whereas the difference in mass loss of leaf litter was not significant at 30℃. The temperature increase did not affect the mass loss of leaf litter for coniferous forest treatment, but significantly reduced the decomposition rate for broadleaf forest treatment. The functional decomposers of microorganism in broadleaf forest produced a higher lignin decomposition rate at 20℃, compared to that in coniferous forest, but the difference in lignin decomposition was not found between two forest types at 30℃. Improved temperature increased the lignin decomposition for both broadleaf and coniferous forest. Additionally, the functional group of microorganism from broadleaf forest showed marginally higher carbohydrate loss than that from coniferous forest at both temperatures. Temperature increase reduced the carbohydrate decomposition for broadleaf forest, while only a little reduce was found for coniferous forest. Remarkable differences occurred in responses between most enzymes （Phenoloxidase, peroxidase, !5-glucosidase and endocellulase） and decomposition rate of leaf litter to forest type and temperature, although there exist strong relationships between measured enzyme activities and decomposition rate in most cases. The reason is that more than one enzyme contribute to the mass loss of leaf litter and organic chemical components. In conclusion, at a community scale the coniferous and broadleaf forests differed in their temperature-decomposition relationships.  相似文献   

4.
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5.
We examined the local community incentive programs to improve traditional forest management in three forested villages in Baneh city, Kurdistan province in the northern Zagros forests of western Iran. Zagros forests cover 6.07 million ha and support rich plant and animal diversity. Changes in local community social and economic sys-tems and the inefficiency of traditional forest management led to a criti-cal situation in the stability of forest regeneration in recent decades. Due to a shortage of productive and arable lands and resulting unemployment and poverty, people overexploited the Zagros forests. Outside interven-tion in traditional forest management creates conflicts between local peoples and forest management organizations. To achieve sustainable forest management, including forest resources conservation and im-provement of natural resource based livelihoods of communities, it is desirable to implement Forestry Incentive Programs （FIP） based on the important functions of forests. Detailed information on the so-cio-economics of communities, the effect of forests on local livelihoods, and lists of products extracted from the forest were obtained from a sur-vey of local communities though questionnaire, interview and observa-tion. We studied 276 households in three villages and completed 76 ques-tionnaires by householders in the quantitative analysis. Sampling was performed by simple random sampling （SRS）. The needs of rural com-munities, such as livestock husbandry, mainly arise from the characteris-tics and environmental features of villages. We identified the driving forces, pressures, status, impacts and responses （DPSIR） to design incen-tive programs, by DPSIR analysis and interaction analysis. Evaluation of local community benefits from forests showed that in order to improve forest management, 319 dollars per year would be needed by each family as an incentive in 2010 to prevent lopping and firewood collecting, the main causes of forest degradation.  相似文献   

6.
Status of organic carbon （C）, total nitrogen （N）, available potassium （K）, calcium （Ca） and phosphorus （P） in three different depths （0-5 cm, 5-15 cm and 15-30 cm） on two hill slopes of 35% and 55% in orange orchard cultivated by the Mro tribe of Chittagong Hill. Tracts （CHTs） were evaluated and compared with those in degraded bush forests, through digging three profiles in each land use. The content of all the five nutrients was found to be higher in the soil of orange orchard than in the soil of forest. But the variation was not consistent for both the slopes. The content varied depth wise also, having the highest value in surface soil in case of both the land uses on both the slopes. A mean available K content was significantly higher in orange orchard than in forest on 55% slope, while it was lower on 35% slope. Surface soil contained the nutrients of K and Ca with the amount of 0.2905-mg·g^-1 soil and 3.025-mg·g^-1 soil respectively in the orchard, while 0.1934-mg·g^-1 soil and 1.6083-mg·g^-1 soil were respectively in the forest. Organic carbon and total nitrogen were found more or less similar in surface soil on both the land uses showing a slight difference. Available P was found only in orange orchard, and in forest it was too little in amount to detect by the spectrophotometer. The degraded forests were poor in nutrient content due to high rate of soil erosion, which would be possible to be improved by bringing it under tree cover as proved by the adaptation of orange orchard there.  相似文献   

7.
The effects of extraction fluids from the leaf litter from different dominant tree species on the functional characteristics of the soil microbial community were studied to understand how changes in soil quality and synergism between plants and soil contribute to the process of forest succession. Leaf litter from dominant tree species at different stages of succession were collected and extracted with sterile deionized water. After treating the soil of abandoned land with the different extraction fluids,we analyzed changes in carbon utilization of the soil microbial community in Biolog Eco Plates, then considered these results with those of our previous study on forest vegetation succession in the Malan forest. The leaf litter enhanced the metabolic capacity and functional diversity of the soil microbes, especially in the following combinations:the leaf litter of Quercus liaotungensis–Pinus tabulaeformis, P. tabulaeformis–Betula platyphylla, Q. liaotungensis and P. tabulaeformiss. Second, when litter from onespecies evaluated, the species enhanced metabolism and diversity in the order of their successional relationship: B.Platyphylla \ P. tabulaeformis \ Q. liaotungensis. After soils were treated with different leaf litters at 25 C for7 days, the sorting pattern of the PCA values, based on the similarity of carbon source utilization by the soil microbes,corresponded to the successional pattern on the basis of the similarity of community composition of forest plants.Thus, changes in soil properties caused by leaf litter from different dominant trees probably play a unique role in the successional pattern of a forest community. We thus propose a successional mechanism that underlies the natural succession process within the Malan forest region. When the dominant forest species of the climax successional stage develops during the early successional stages, its forest litter probably alters soil properties such that the soil becomes unsuitable for the gradual growth and regeneration of the original dominant tree species but promotes the growth and establishment of later-invasive plants. In this way, the originally dominant species is replaced by the newly dominant tree species during forest succession.  相似文献   

8.
We identified the major non-timber forest products （NTFPs）, their contributions to household incomes, and the determinants influenc-ing engagement of households in using NTFPs in the Bonga forest area of Gimbo and Decha Districts of Kaffa Zone, southwest Ethiopia. Six Kebeles （the lowest administrative unit in Ethiopia） were sampled from two Districts and 150 households were randomly sampled using propor-tional-to-size techniques based on the number of farm households in each Kebele. Secondary data were collected from and focus group discussions were conducted with selected individuals. The farmers diversified liveli-hood activities such as crop and livestock production, collection of NTFPs and off-farm activities. NTFPs played a significant role in household incomes. The contribution from the major NTFPs （forest coffee, honey and spices） accounted for 47% of annual household in-come. The role of NTFPs was influenced by a number of factors. Vari-ables including being native to the area （＋）, total land holding （＋）, pos-session of livestock （＋） and access to extension （＋） significantly affected forest coffee production. Age of household head （-）, land holding （＋） and distance of the market from the residence （-） significantly affected honey production. Size of landholding （＋）, distance to market （-） and distance of the forest from the residence （-） were significant variables determining the NTFP incomes derived by the households. Attention is needed in the design of policies and strategies for the well-being of households to the contribution of NTFPs to local incomes and the variables that affect the collection of NTFPs must be considered.  相似文献   

9.
Status of urban vegetation in Guangzhou City   总被引：11，自引：0，他引：11  
According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey for soil, species diversity, roadside trees and ecological function of urban vegetation in Guangzhou City. The results showed that: (1) soil densities of urban roadside and park forests were higher than mean density of natural forest soil. The pH values of soil in urban roadside were higher too, and the content of organic matter and the concentration of nitrogen were lower. (2) Species diversity of urban vegetation was lower. The most number of species was only 16 species in tree layers of urban forest. (3) Tree growth was limited by narrow space in high-density urban area, where the trees with defects and disorders were common. (4) Comparing with mature natural forests, the productivity of urban vegetation was lower. The effect of urban vegetation on balance of carbon and oxygen were influenced by the low primary production of urban vegetation. Therefore, the growth condition for urban vegetation should be improved. Biodiversity, primary production and ecological function should be increased for urban vecletation in order to improve urban eco-environment.  相似文献   

10.
We analyzed the tolerance of Copaifera lucens seeds to sub- mersion in water to assess the use of this species for direct seeding in riparian forest restoration programs. Seeds were submerged in water for 2, 4, 8, 16 and 32 days or not submerged （control = 0 days of submer- gence）. For the control and at the end of each period of submersion, germination and seedling vigor tests were carried out. For germination tests, seeds were sown in plastic pots containing sand and kept in labora- tory conditions. The percentage of seed germination, the germination rate and the average germination time were analyzed. For seedlings, total biomass, leaf area, leaf mass per area and leaf area ratio were analyzed. Submersion time drastically affected the dissolved oxygen content and seed germination. Between 4 and 8 days of submersion there was a de- crease from 83.8% to 15.6% in the germination percentage. No seed germination occurred after 16 days of submersion. Although there was a significant decrease in the percentage of seed germination between 4 and 8 days of submersion, seedling vigor was not affected. Seeds of this species were partially tolerant to submersion in water, suggesting that C. lucens is a promising species for direct seeding in riparian forest restora- tion projects.  相似文献   

11.
A study was conducted to investigate the cultural and financial management techniques of betel leaf based agroforestry system practiced in or near homegardens of Khasia community in Jaintapur Upazila in the district of Sylhet, Bangladesh. The Khasia is an educated community where 100% of Khasia people were literate, a stunning fact for this ethnic community in Bangladesh. The average family size in the study area was 7.68, with a ration of male and females of 141:100. The homegardens of the Khasia are rich in species composition, which 15 timber species, 22 horticultural species, six medicinal species, 13 annual crops including leafy vegetables, seven species of spices and five species of bamboo were identified along with betel leaf. The Khasia is an economically prosperous community with the minimum family incomes of Tk 4000 per month (Tk. 70=1 US Dollar). Betel leaf based agroforestry is very common being a prevalent source of income. About 95.45% of the households are involved in betel leaf husbandry. The mean annual income from one hectare of betel leaf plantation was estimated to be Tk. 80979. This practice was proven to be a profitable business where the benefit cost ratio was calculated to be 4.47. Moreover, the species composition in the betel leaf plantation area (the forest area once utilized by Khasia for shifting cultivation) was found to be very promising to play the significant role in conservation of biological diversity making the practice a sustainable agroforestry system.  相似文献   

12.
The Khasia ethnic community of Bangladesh has been a population of forest villagers in the north-eastern hill forests of Bangladesh since the early 1950s, practicing a betel leaf-based agroforestry system on land granted by the Forest Department. Taking a sample forest village of the Sylhet forest division as a case study, this article examines the sustainability attributes of betel leaf production in the agroforestry system. The presence of several positive attributes of sustainability including the composition of agroforestry, disease control, soil fertility management, profitability, socio-cultural acceptability and institutional support indicate that betel leaf production within the agroforestry system is stable under the prevailing traditional management system. Income from the sale of betel leaf is the principal livelihood means and villager’s reciprocal contributions help to conserve forest resources. However, problems with land ownership and regular agreement renewal need to be resolved for the sake of their livelihoods and forest conservation.
Tapan Kumar NathEmail:
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13.
Rapid economic growth of the Khasia people has resulted from a most successful betel leaf farming system practiced within the fringe of reserved forests, where government policies have facilitated effective use of the local people as a labour force for production, protection and conservation of biodiversity of the surrounding forests. Khasia tribes have traditionally grown betel leaf plants on naturally occurring trees. Deforestation is a serious problem in Bangladesh, whereas the Khasia people living within forests are protecting trees for their livelihood, including selling betel leaf, collecting fuelwood and consuming and selling fruits from support trees. It is a profitable yet sustainable forest production system, maintaining soil fertility, stable production and optimal family size, and has created employment opportunities for the people living within and outside the forests. It has enhanced the supply of socially required betel leaf to the local markets, contributed to price stability, and generated some export revenue. However, the revenue of growers has been reduced by plant diseases and the capture of resource rent by middlemen. Economic benefits could be further increased through government initiatives to improve management and the marketing system. This paper is based on a presentation at the International Conference on Economics of Sustainable Forest Management, University of Toronto, Canada, May 20–22, 2004.  相似文献   

14.
Even though many forest villagers have been living on forest department land and serving the department in the northeastern hill forests region of Bangladesh since the early 1950s, their livelihood has not yet been fully explored. This paper examines the livelihoods of forest villagers (Khasia ethnic people) and their contribution to forest conservation, using data from the Sylhet forest division. The forest villagers are well-endowed with all the elements of a sustainable livelihoods framework, though human capital in terms of education is not satisfactory. Strong social capital, stable natural capital and a productive market-oriented agroforestry system facilitate the generation of financial and physical capital that make the livelihoods of Khasia people sustainable. At the same time, their reciprocal contributions in terms of forest protection and plantation development support forest conservation. However, some institutional issues such as insecure land tenure with regular agreement renewal problems need to be resolved for the sake of their livelihoods and forest conservation. Lessons learned from the study can be utilized in formulating future participatory forest management schemes in the country.  相似文献   

15.
Throughout the world ornamentation of body with mehedi (Lawsonia inermis L.) leaf paste, with the trade name ‘henna body art’ is becoming increasingly popular. The worldwide increasing demand of mehedi leaf encourages many countries to adopt commercial farming of the plant. Farmers living in central Bangladesh recently commenced small-scale mehedi farming, primarily with the purpose of meeting national demand. A total of 182 farmers are engaged in mehedi farming and a study was conducted among 36 of them (a 20% random sample) to explore indigenous management techniques, marketing, livelihood potential and constraints of the enterprise. Farming was reported to be the major primary occupation of the study area. An average of 0.05 ha land of the respondents was used for mehedi cultivation, which constituted 16.7% of their average farm land. The farmers applied their own indigenous technology in every aspect of the farming, using branch cuttings as the only propagation material. The financial analysis indicated that mehedi farming is a profitable and attractive option for rural livelihoods [with an estimated net present value of Tk (Bangladeshi currency unit, 1 US $ = 68 Taka (as of May, 2009).) 179,500 for 0.1 ha plantation]. However, the enterprise faces several constraints, including absence of a nursery for supplying planting materials, storage and effective marketing facilities, available capital for investment, improved technology, and above all, government support. If the government extends cooperation by assisting farmers with training, technology, credit and market development, mehedi farming could become an important revenue-earning enterprise in the small-scale cottage sector of Bangladesh.  相似文献   

16.
Forest values play an important role in forest management practices, and in the design and implementation of forest policy and the legal framework. This paper assesses the importance of farmers’ forest values and the potential associations between farmers’ forest values and their compliance with the tree-felling rule in Ghana. The results are derived from a survey with farmers, inhabiting fringes of forest reserves in the High Forest Zone of Ghana. With the exception of the forest value for future generations, forest values that contribute to immediate subsistence and livelihoods are perceived as the most important (i.e. environmental, subsistence and economic forest values). These values provide, among others, wide variety of foods, such as wild crops and bushmeat, farming land, medicinal plants, household items such as ropes, lianas and mats, firewood and shelter. Aesthetic and religion-related forest values are considered to be the least important. Multivariate binary logistic regression analysis suggests that farmers’ forest values may to some extent influence their compliance with the tree-felling rule. Economic, religion-related and learning forest values are likely to encourage compliance with the tree-felling rule.  相似文献   

17.
Community forest management helps in mitigating deforestation and forest degradation by addressing the negative aspects of rural livelihoods such as poverty and social exclusion. It is important in regulating global climate by encouraging sequestration of carbon in shoots, roots and soils. We studied the status of community forest management, forest resource harvest and carbon stocks in two community forests of the mid hill region of central and western Nepal. The study was based on primary and secondary data collected through carbon stock measurement from field visits and allometric equations, household surveys, focus group discussions, key informant interviews, and review of past studies. Socioeconomic variables such as gender, age group, livestock and landholding status were related to resource utilization, conservation, and management of community forest. Forest resources such as timber, firewood, fodder and leaf litter were harvested in sustainable ways. People were involved in forest thinning, co-management meetings, guarding and planting trees for forest conservation and management. Density and carbon stock of trees increased gradually in comparison to a previous study. We recommend further research on other community forests for more accurate and better results.  相似文献   

18.
This study examines the strategies and benefits of the taungya farming system to both the government and the rural economy in Nigeria. An interview survey was conducted in which data were collected from 115 randomly selected farmers in five villages in the Oluwa forest reserve, Ondo State, Nigeria. The study examines the extent of participation of rural dwellers in plantation development through taungya farming and the degree of success of this system as an afforestation method. The farmers were predominantly illiterate, within the age bracket of 35–54 years and with small farm holdings. Twenty nine percent relied totally on food from the forest reserve for their livelihood, while 71% also had farm holdings in free areas. Land within the reserve is allocated to farmers free of charge but compensation is paid to landlords on land from free areas. A statistically significant difference was detected in income from the two sources of farmland for the households and but not in the size of land allocated under taungya and free areas. About 184 farmers are involved in taungya annually, and 410 ha of Tectonia grandis has been established for the government of Ondo State.  相似文献   

19.
Agroforestry is one of the most sustainable land management systems practiced around the world due to the socioeconomic benefits that it brings to farmers. In Bangladesh, farmers practice agroforestry, applying indigenous knowledge. The present study was designed to identify the present status, management practices and its role in improving the livelihoods of farmers in northern Bangladesh. Data for the study were collected through quantitative and qualitative methods. A total of 29 tree and 38 agricultural crop species were planted by the102 farmers interviewed. Mangifera indica (relative prevalence 49%) is the most predominant species, followed by Eucalyptus camaldulensis (relative prevalence 35.4%). Farmers of northern Bangladesh plant trees in cropland for fruits (90%), fuel wood (87%) and timber production (79%). Fruit trees were planted with wider spacing while forest and fuel wood species were planted with narrower spacing. Farmer’s livelihoods improved enormously by practicing agroforestry as they have more access to food, fodder and fuel wood which is reflected by greater access to livelihood capitals (except social capital). However, farmers have experienced increased incidences of pests and diseases to the annual crops and trees. Agroforestry practices increases species diversity, ensure economic return and sustain farmer’s livelihoods.  相似文献   

20.
Domestication of desirable forest resources in agroforestry is expected to contribute to community based forest conservation efforts, but there may be an optimum level of domestication in this respect. Aren or sugar palm (Arenga pinnata (Wurmb) Merr.) is a multipurpose tree that provides livelihoods for local people and food for other biota in the landscape. However, its domestication is still limited in many places, such as in Batang Toru Forest Block, an area of high conservation value, including habitat for the Sumatran orangutan (Pongo abelii). Options for aren management were prioritized as part of a landscape-scale conservation study by comparing domestication levels in the area. Data on economic indicators and ecological knowledge were gathered through interviews with key farmers, focus groups and transect walks. Four representative villages were selected for the study, that is, (i) two villages with no domestication of aren; and (ii) two villages with aren cultivation in rubber-based land-use systems. Costbenefit analyses suggested that in a rich biodiversity area, such as Batang Toru, although aren was one of the sources of local livelihoods, additional investment for domestication beyond cultivation was not an option considered by farmers. Farmers still perceived wildlife as an efficient mode of aren regeneration, supported by the coexistence of people and other biota in the area. It appears the value of aren for local people’s livelihoods and conservation can be enhanced by increasing its stocking density. There is also scope for improving market access and share of end-user value received by farmers.  相似文献   

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