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11.
Over recent decades there has been a growing interest in the attributes of non-timber forest products (NTFPs) to food security, income generation, and poverty alleviation. In the Guinean Savannah Highlands (GSH) of West Africa, species producing these products are still in wild stands where they are subjected to various pressures. To conserve these species, their domestication is required. Air layering is a low-cost propagation technique easy to use by farmers. The present study aims at evaluating the effects of the wood type (hardwood, semi-hardwood, and softwood) as well as branch diameter (Φ ≤ 6.67 cm; Φ > 6.67 cm) in the rooting ability of the marcots (air-layered propagules) of Lophira lanceolata Van Tiegh. Ex Key., Parkia biglobosa (Jacq.) Benth, Syzygium guineense var. macrocarpum Engl., Vitex doniana Sweet., Vitex madiensis Oliv., and Ximenia americana L. The experimental design was a split-plot with three replications. The rooting percentage of the marcots varied significantly from 13.5 (X. americana) to 55.85% (Lophira lanceolata; p < .001). The diameter * wood type interaction was significant (p < .05) due to the high rooting percentage obtained in large semi-hardwood cuttings (40%). Lophira lanceolata, Syzygium guineense var. macrocarpum, and Vitex madiensis were the easiest marcotting rooting species. Large branch diameters as well as semi-hardwood are suitable for layering. This information will help in developing appropriate domestication strategies. 相似文献
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LIU Tong ZHOU Zhi-qiang 《林业研究》2006,17(4):339-341
Introduction of Sanjiang Plain The Sanjiang Plain is a vast area of alluvial floodplains and low hills in northeast Heilongjiang Province, China. It is characterized by the confluence of three major rivers, the Heilong River (Amur in Russia), the Wusuli R… 相似文献
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Himalayan medicinal plants are threatened by large scale exploitation for trade. Research applicable to their sustainable use is largely lacking. We analyze the effects of different harvesting patterns on the population ecology of two highly threatened Himalayan medicinal plants, Nardostachys grandiflora (Valerianaceae) and Neopicrorhiza scrophulariiflora (Scrophulariaceae), in Shey-Phoksundo National Park and in its buffer zone in northwestern Nepal. We first documented local harvesting approaches of two major user groups, amchi (traditional doctors trained in Tibetan medicine), who harvest plants in a selective manner for local health care purposes, and commercial collectors, who harvest unselectively and at much higher intensity for trade. We then applied the selective harvesting approach of amchi in an experiment to test the effects of different harvesting levels on the population ecology of these two species. These experiments revealed a positive effect of low harvesting levels on plant density, but recruitment and survival rates decreased with increasing harvesting levels. We also analyzed the effect of high harvesting pressure for trade on the population ecology of N. grandiflora. Recruitment and survival rates were higher in N. scrophulariiflora than in N. grandiflora; the latter species is more vulnerable to harvesting than the former. The difference between them in sustainability of harvest is related to differences in their strategies of vegetative reproduction and in harvesting practices associated with these strategies. Management of Himalayan medicinal plants can be improved by taking harvesting patterns, plant life forms and growth patterns into consideration. 相似文献
14.
Leonel Lopez-Toledo Christa Horn Bryan A. Endress 《Forest Ecology and Management》2011,261(11):1901-1910
The use of non-timber forest products (NTFPs) has great potential for the conservation of natural resources and rural development. Palms are important NTFPs, providing numerous products, including leaves. The harvest of palm leaves rarely results in the immediate death of individuals and can be considered one example of the sustainable use of forest resources. However, in most cases basic ecological information, such as distribution and abundance of the species is unknown, as is information on the ecological implications of human impacts, such as leaf harvest and livestock grazing. In the tropical dry forests of northwest Mexico, leaves from the threatened palm Brahea aculeata are harvested for roofing material and represent an important NTFP. In this study, we assessed the distribution and abundance patterns of this species across 52 plots in the tropical dry forest of Sierra de Álamos-Rio Cuchujaqui Reserve (SARCR) in Sonora, Mexico. We also evaluated patterns of leaf harvest and cattle browse intensity on palm populations. We found that B. aculeata density is highly variable across the landscape with a mean (±SE) of 121.7 ± 36.3 ha−1. Results indicate that B. aculeata is primarily distributed near to arroyos and rivers. The highest densities were found in sites with low incidence radiation (<0.06 MJ cm−2) and narrow stream width of arroyos/rivers (<9.5 m). Palm abundance also varied within the plots, and B. aculeata attained its highest densities near to the arroyo edge (first 20 m from the edge), perhaps indicating a microhabitat effect on palm demography. Overall, fewer than 6% of the stems were seedlings. Leaf harvesting and browsing appear to affect demographic vital rates of the species; specifically we found a significant effect of harvesting and browsing activity on the proportion of reproductive active adults. Thus, low levels of seedlings in the populations may be the result of reduced fruit production by adults and higher mortality rates of seedlings due to livestock herbivory. Result from interviews with land owners also indicated that past land use, especially along arroyos might also have important impacts on the observed distribution, low densities and absence of recruitment in some areas. We believe current distribution and abundance of NTFP, such as B. aculeata at SARCR may be a result of combined effects of environmental factors and human impacts. Results from this study will be used to develop appropriate conservation, management and restoration plans of B. aculeata in the area. 相似文献
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中国的山区面积占陆地面积的2/3,农村64%的人口居住在山区。非木质林产品的生产与农村（山区）的发展及基于林分的生态环境紧密相关。森林可持续经营认证是基于市场机制的促进森林可持续经营的工具,森林认证工作的开展在国际上已越来越多地引起人们对环境友好型及社会效益良好的林产品的认同。经营良好的林分往往能在经济、环境和社会方面达到标准,而这些标准可以确保林分的可持续经营。森林认证（含非木质林产品认证）就是按照这样的标准来进行操作的。从森林认证中的环境和社会影响评价及环境可持续发展的角度,就非木质林产品生产、农村发展与环境的可持续发展进行了论述,认为我国在森林认证尤其是在林分生物多样性的维持与恢复,森林认证相关知识的普及,社会影响评价与环境影响评价方面存在较多问题,任重而道远。参11 相似文献
16.
浅述云南石斛资源现状及开发利用技术 总被引：7，自引：0，他引：7
石斛是常用名贵中药材，应用广泛。但石斛属植物自然繁殖力极低，生长缓慢，加之掠夺性采挖，致使野生石斛资源已经严重枯竭。石斛的栽培也一直存在着成活率低、产量低等问题，因此，石斛药源一直处于紧张状态，亟待解决。结合云南省林下资源开发，走组织培养与栽培相结合之路，通过人工栽培扩大资源量，实现石斛资源的保护和可持续利用。 相似文献
17.
Andrea Martínez-Ballest Carlos Martorell Javier Caballero 《Forest Ecology and Management》2008,256(6):1320-1324
Palm leaves are an important resource for family households. The effect of harvest on leaf production, growth and fecundity of wild individual palm trees has been studied, but little is known about palm harvest in agro-forestry systems. In the Maya area of the Yucatán Peninsula, Mexico, leaves of the xa’an palm (Sabal yapa, and Sabal mexicana) have been used since pre-Hispanic days for thatching the roofs of traditional Maya houses. The Maya have introduced xa’an palms in homegardens and the care they provide them improves their growth. Maya householders agree on what they consider to be the best harvest intensity for xa’an, recommending one or two harvest events per year, and leaving one or two leaves in each event; however, there is not ecological information documenting whether the traditional harvesting practices are the most adequate to maintain or increase leaf production, and their effect on the growth and fecundity of the palm trees. In Maxcanú, Yucatán, we studied eight family homegardens with S. yapa and S. mexicana. The selected individuals from each homegarden (n = 252) underwent six harvest treatments for 2 years C: control, no harvest, Al: annual harvest, leaving three leaves on the palm, Am: annual harvest leaving two leaves, Ah: annual harvest leaving one leaf, Sl: two harvests per year leaving three leaves, Sm: two harvests per year leaving two leaves. Treatments Ah and Sm simulated the traditional harvest method, and the remaining treatments simulated higher or lower harvest intensities and frequencies. Leaf production was higher in individual palms under higher harvest intensities and frequencies (Ah, Sl and Sm), but palm growth and leaf size were not affected by harvest. Number of inflorescences per palm differed between treatments and between homegardens during the first year only, but we could not find a clear pattern of variation. Production of new leaves was affected by initial palm size and initial leaf number. Removing mature leaves while leaving the young ones, as well as the intensity and frequency, with which traditional harvest is practiced, stimulate palms to compensate the defoliation effects by producing new leaves. This practice is based on empirical Maya knowledge that enables the manipulation of micro-environmental conditions and the development of sustainable harvesting strategies for the xa’an palm in traditional agro-forestry systems. 相似文献
18.
We identified 67 and 21 NTFP-yielding plant and animal species, respectively, in a reserve forest in Cachar district of Assam. We recorded globally threatened species listed by IUCN as Critically Endangered （plant species Dipterocarpus turbinatus）, Vulnerable （plant species Aquillaria malaccensis）, Endangered （animal species Hoolock hoolock, Indotestudo elongata and Manis pentadactyla）, and Vulnerable （animal species Nilssonia hurum and Rusa unicolor）. The whole plant or animal and/or their various parts were used as food or medicine, in house construction, magico-religious activities and others. While some NTFPs were harvested throughout the year, others were harvested seasonally. A comprehensive NTFP policy, along with scientific measures for regen- eration, restoration and augmentation of NTFP-yielding plants and animals, would help in addressing the conflicting demands of conservation and livelihood in the forests of this area. 相似文献
19.
Why do local households harvest forest products? A case study from the southern Western Ghats, India
Deforestation in tropical countries has been partly attributed to the non-sustainable harvesting of forest biomass by local communities. We conducted a survey among 786 households in 31 agricultural villages adjoining the eastern boundary of the Kalakad-Mundanthurai Tiger Reserve, in the southern Western Ghats to see whether household wealth, social status, literacy and distance to the forest boundary influenced resource harvesting. Fuel-wood, fodder and green leaves were the major products harvested in this agricultural region. The effect of distance from the reserve boundary differed with the product harvested and its use value. Distance was a constraint for households that harvested for domestic consumption, whereas it was not significant for households that harvested for earnings. Wealth was independent of resource interest in the forest, except for the poorer lower caste households with lower levels of literacy that sold fuel-wood to earn a living. Wealthier households harvested green leaves for fertilizing their fields, and fodder harvest was related to livestock ownership. The lower cost of forest products compared to commercially available substitutes probably fuelled extraction. Forest products contributed disproportionately to household consumption as compared with household earnings. Discouraging the harvest of forest products within protected areas might be the only viable conservation strategy. 相似文献
20.