Drivers of adoption of eucalypt tree farming by smallholders in Thailand     

Axelle Boulay  Luca Tacconi  Peter Kanowski 《Agroforestry Systems》2012,84(2):179-189

Eucalypt (Eucalyptus spp.) tree farming is a source of income for many smallholders in developing and emerging countries and critical to the resource supply of many pulp and paper companies. These companies rely on smallholders adopting tree farming, sometimes by offering a contract. This paper reports a study from four regions of Thailand, where smallholder eucalypt tree farming is important, which investigated what characteristics of smallholders were associated with greater adoption of tree farming. A total of 461 eucalypt tree farmers and 171 non-tree farmers were randomly selected and surveyed in these regions, using a door-to-door household survey. A logit analysis corroborated hypotheses about the drivers of adoption. Qualitative analyses were used to inform interpretation of the quantitative results and shed light on the role of eucalypt tree farming in smallholders’ livelihood. Results demonstrate that those with suitable land available are more likely to adopt eucalypt tree farming than others. In addition, perception of land tenure security matters in the adoption of tree growing, but holding a formal land tenure document does not. Adoption of eucalypt tree farming in Thailand is not part of a land use intensification strategy. Instead, eucalypts are used as an alternative crop for low productivity land, on which eucalypts are the most profitable crop. Eucalypt tree farming also gives smallholders an opportunity to diversify their income. In addition, this alternative land use has the advantage of requiring low labour inputs between planting and harvest. This is particularly advantageous for many tree growers who have off-farm income or rely on hired labour for farming their land.  相似文献   

Traditional agroforestry systems of multi-crop “milpa” and “chichipera” cactus forest in the arid Tehuacán Valley,Mexico: their management and role in people’s subsistence   总被引：2，自引：2，他引：0  

Ana Isabel Moreno-Calles  Alejandro Casas  Eduardo García-Frapolli  Ignacio Torres-García 《Agroforestry Systems》2012,84(2):207-226

Agroforestry systems (AFS) derived from the cactus forest “chichipera” and cultivated with “milpa”, the traditional multi-crop system of maize-beans-squash were studied in the Tehuacán Valley, Mexico. Plant management types practiced by people, role of agricultural and forest resources in households’ subsistence, and consequences of changes in AFS were investigated through ethnobotanical, ecological, and economic approaches. People maintain in this AFS 122 plant species that provide useful products for 14 different purposes. Nearly 90% of useful plants are native to the region, representing 54% of all plant species recorded in the chichipera forest. Management strategies were identified occurring on 63 species at landscape, parcel, and individual plant levels. About 67% of managed plant species are left standing during clearance of vegetation; 35% are transplanted to the parcels’ surrounding area, 32% receive particular protection, and 10 species from other areas are cultivated inside the fields. During years of higher rainfall (~745 mm) AFS supply nearly 75% of the maize grain and 50% of the maize straw used as fodder by households. AFS with intermediate vegetation cover have higher economic value than monocultures and forest. However, plots with low forest cover and monocultures are progressively more common as consequence of socio-cultural processes. Local traditional ecological knowledge and management techniques are crucial for managing resilience of these AFS.  相似文献   

Erratum to: Phenology,pollination and breeding system of <Emphasis Type="Italic">Aegle marmelos</Emphasis> (Linn.) Correa (Rutaceae) from India     

Vijay Kumar Singhal  Atula Salwan  Puneet Kumar  Jaspreet Kaur 《New Forests》2012,43(3):395-395

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Are composts from shredded leafy branches of fast-growing forest species suitable as nursery growing media in arid regions?     

Mustapha Bakry  Mohammed S. Lamhamedi  Jean Caron  Hank Margolis  Abdenbi Zine El Abidine  M’Hammed Bellaka  Debra C. Stowe 《New Forests》2012,43(3):267-286

The morpho-physiological quality of seedlings is negatively affected by the wide scale use of forest soils as substrates in developing countries. With the objective of finding long-term sustainable supply of growing media, compost was produced from shredded branches of three fast growing species (Acacia cyanophylla (AA), Acacia cyclops (AS) and Eucalyptus gomphocephala (EG). The composting process covered three different periods over the course of a year. Pile temperatures were monitored daily and the composts were routinely sampled and analyzed for 19 chemical variables. Although composting is feasible year-round in arid climates, compost produced in the humid cool conditions of autumn, winter and early spring reaches the maturation phase more quickly than compost produced under hot, dry summer conditions. It also requires less turning and water. The evolution of the composting process and quality of the final product can be assessed using three chemical variables (C/N, pH, EC). Seed germination rates in the three types of compost were similar to that in a peat:vermiculite substrate and vigorous high quality seedlings were produced in the two acacia composts. However, compost-grown seedlings had significantly smaller shoots and root systems than those produced in peat substrate. Principal components analyses showed that the quality of a compost-based substrate is reproducible and that its final chemical composition can be predicted from its raw organic materials. The EG composts had higher pH than the acacia composts, whereas the AA and EG composts were higher in mineral salts than the AS.  相似文献   

Effects of seed traits on the success of direct seeding for restoring southern Thailand’s lowland evergreen forest ecosystem     

Panitnard Tunjai  Stephen Elliott 《New Forests》2012,43(3):319-333

The success of direct seeding, as a low-cost approach to forest restoration, varies with tree species and seed characteristics. A system to predict which tree species are likely to be suitable for direct seeding would therefore be useful for improving forest restoration projects. Therefore, this study aimed to determine the effects of seed traits on the success of direct seeding to restore tropical forest in southern Thailand. Seeds of 19 indigenous lowland tropical forest tree species were collected, from both the east and west sides of the Thailand peninsular and the following parameters measured: seed size, shape, coat thickness and moisture content. Field trials were established to determine seed germination rates and to calculate a “direct seeding suitability score” for each species, which combined seedling establishment and growth rates. Seed size, shape and moisture content were associated with germination percentage. Species with higher seedling survival tended to have large or intermediate-sized seeds, round or oval seeds and seeds with low or medium moisture content. Only seed coat thickness was significantly correlated with the suitability score (r = 0.65, p < 0.01). Seed coat thickness >0.4 mm coincided with higher rank suitability score. These conditions successfully predicted the success or failure of direct seeding for 15 out of 19 species tested. Eight tree species are recommended as suitable for restoring lowland evergreen forest ecosystems in southern Thailand, by direct seeding.  相似文献   

Occurrence of pathogenic fungi to Amblyomma cajennense in a rural area of Central Brazil and their activities against vectors of Rocky Mountain spotted fever     

D'Alessandro WB  Humber RA  Luz C 《Veterinary parasitology》2012,188(1-2):156-159

Two isolates of Beauveria bassiana and one of Purpureocillium lilacinum (=Paecilomyces lilacinus) were found infecting Amblyomma cajennense engorged females collected on horses (0.15% infection rate from a total of 1982 specimens) and another two isolates of P. lilacinum and one Metarhizium anisopliae detected in soils (2.1% from 144 samples) collected in typical pasture habitats of this tick in Central Brazil from October 2009 to March 2011. Fungi were isolated from soils with Rhipicephalus sanguineus as surrogate baits. No fungi were found in ticks or soils during the driest months (May to August). Testing pathogenicity of fungi all R. sanguineus females were killed regardless of the isolate and fungi sporulated abundantly on the cadavers. A. cajennense was less susceptible to infection with P. lilacinum within 20 days than R. sanguineus. All three fungal species probably act as natural antagonists of A. cajennense particularly in the rainy season and have interest for integrate control of vectors of Rocky Mountain spotted fever.  相似文献   

First record of Taenia ovis krabbei muscle cysts in muskoxen from Greenland     

Raundrup K  Al-Sabi MN  Kapel CM 《Veterinary parasitology》2012,184(2-4):356-358

A first record of Taenia ovis krabbei muscle cysts in a muskoxen (Ovibos moschatus) from the Kangerlussuaq population in West Greenland suggests that introduced muskoxen now contributes to the transmission of this parasite in addition to previous observations from caribou (Rangifer tarandus). Muskoxen and caribou are the only wild ungulates in Greenland.  相似文献   

Impact of species-specific dispersal and regional stochasticity on estimates of population viability in stream metapopulations     

Mark S. Poos  Donald A. Jackson 《Landscape Ecology》2012,27(3):405-416

Species dispersal is a central component of metapopulation models. Spatially realistic metapopulation models, such as stochastic patch-occupancy models (SPOMs), quantify species dispersal using estimates of colonization potential based on inter-patch distance (distance decay model). In this study we compare the parameterization of SPOMs with dispersal and patch dynamics quantified directly from empirical data. For this purpose we monitored two metapopulations of an endangered minnow, redside dace (Clinostomus elongatus), using mark-recapture techniques across 43 patches, re-sampled across a 1 year period. More than 2,000 fish were marked with visible implant elastomer tags coded for patch location and dispersal and patch dynamics were monitored. We found that species-specific dispersal and distance decay models provided qualitatively similar rankings of viable patches; however, there were differences of several orders of magnitude in the estimated intrinsic mean times to extinction, from 24 and 148 years to 362 and >100,000 years, depending on the population. We also found that the rate of regional stochasicity had a dramatic impact for the estimate of species viability, and in one case altered the trajectory of our metapopulation from viable to non-viable. The divergent estimates in time to extinction times were likely due to a combination species-specific behavior, the dendritic nature of stream metapopulations, and the rate of regional stochasticity. We demonstrate the importance of developing comparative analyses using species- and patch-specific data when determining quantitative estimates for mean time to extinction, which in the case of redside dace, were highly sensitive to different estimates of dispersal.  相似文献   

An integrated approach of remote sensing,GIS and swarm intelligence for zoning protected ecological areas   总被引：1，自引：0，他引：1  

Xiaoping Liu  Chunhua Lao  Xia Li  Yilun Liu  Yimin Chen 《Landscape Ecology》2012,27(3):447-463

Interest in protecting ecological areas is increasing because of land uses conflicts and environmental pressures. The optimal zoning of protected ecological areas belongs to a NP-hard problem because it is subject to both box and spatial constraints. A challenge in solving area optimization problems emerges with the increasing size of a study region. In this article, an integrated approach of remote sensing, GIS and modified ant colony optimization (ACO) is proposed for application in zoning protected ecological areas. Significant modifications have been made in the conventional ACO so that it can be further extended to solve zoning problems in large regions. An improved selection strategy is designed to accelerate the progress of sites selection for artificial ants. Another important modification in ACO is to incorporate the neighborhood diffusion strategy into pheromone updating. The optimal objective is to generate protected areas that maximize both ecological suitability and spatial compactness. The modified ACO model has been successfully applied to a case study involving an area of 25,483 cells in Dongguan, Guangdong, China. The experiments have demonstrated that the proposed model is an efficient and effective optimization technique for generating optimal protection. The modified ACO model only requires approximately 119 s for determining near-optimal solutions. Furthermore, the proposed method performs better than other methods, including simulated annealing, genetic algorithm, iterative relaxation, basic ACO, and density slicing.  相似文献   

Timing of breeding in <Emphasis Type="Italic">Ochrotomys nuttalli</Emphasis> and <Emphasis Type="Italic">Peromyscus leucopus</Emphasis> is related to a latitudinal isotherm     

Nathan L. Pratt  Gary W. Barrett 《Landscape Ecology》2012,27(4):599-610

Previous comparative studies on patterns of reproduction in small-mammal species focus primarily on latitudinal differences in average litter size. Few studies compare reproductive patterns among northern and southern populations at the landscape scale. Our study compares differences in seasonal patterns of reproduction in northern and southern populations of the golden mouse, Ochrotomys nuttalli, and the white-footed mouse, Peromyscus leucopus. These are remarkably similar species with regard to bioenergetics, body mass, feeding behavior, home-range size, natural history, nest-site preference, and periods of activity. Both species also exhibit very similar intraspecific seasonal patterns of reproduction across their respective geographic ranges. We found that O. nuttalli and P. leucopus switch from a summer breeding season, extending from late spring through early autumn in the north to a winter breeding season extending from late autumn through early spring in the south, near the isotherm where mean annual temperature is 15.6°C (60°F), or approximately 35° N latitude. This latitudinal isotherm provides a geographic benchmark to address future changes in patterns of reproduction attributed to climate change. Findings also suggest that length of the breeding season and patterns of reproduction between species partially explain why P. leucopus is typically more abundant than O. nuttalli in similar habitat types.  相似文献