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1.
1. Until the late 1960s, Euterpe edulis was the most important edible palm species in the Brazilian markets. Since then, overharvesting of natural stands and the limited scope of plantations have caused the industry to shift to the multistemmed E. oleracea from the Amazon river estuary.
2. As a result of the relocation of the industry, the structure of the palm harvesting industry has changed and illegal trade has continued to exploit the remaining natural stands of E. edulis .
3. It is suggested that, to avoid the total harvesting of E. edulis and to achieve sustainable management of the palm heart, it will be necessary to diversify the local economy, create incentives for small land owners to improve their management practices, while keeping their competitiveness against the illegal trade, create the incentive of new sources of palm hearts and create a 'green stamping' for management palms.
4. Transformation of the illegal structure of the palm heart industry is probably the only solution to avoid the total depletion of the wild stands of E. edulis .  相似文献   
2.
The availability of fruits is critical for tropical forests, where the majority of plant species rely upon animal vectors for seed dispersal. However, we do not know how fruit production is temporally distributed over species and families. Two plant families are particularly important in floristic inventories of Atlantic rain forests: Arecaceae, a few species of which are highly abundant; and Myrtaceae, which is abundant and displays outstanding species diversity. In this context, we asked whether hyperdominance occurs in fruit production in the Atlantic rain forest, and whether it occurs in the abundant species of Arecaceae and Myrtaceae. We investigated whether the temporal fruit production patterns differ between Myrtaceae, Arecaceae, and the plant community as a whole. We also applied a functional dispersion index to assess the temporal fruit diversity over a 2‐yr period, with regard to morphological and phenological traits. We found that the phenomenon of hyperdominance occurs in fruit production: five species accounted for more than half of the pulp biomass. Arecaceae fruit biomass peaked at the end of wet season, overlapping with the community peak; whereas Myrtaceae species fruited throughout the year and were an important resource during periods of food scarcity. Myrtaceae filled more of the fruit morphospace over time because their fruits exhibit a large range of morphologies and phenological strategies. Our results demonstrated the importance of combining phenology and fruit morphology in the evaluation of resource availability, which revealed periods of high fruit diversity that could support a range of frugivore sizes and maintain overall ecosystem functionality.  相似文献   
3.
The establishment of plants depends crucially on where seeds are deposited in the environment. Some authors suggest that in forest understory seed predation is lower than in gaps, and higher than at the forest edge. However, most studies have been carried out in large forest patches and very little is known about the effects of microhabitat conditions on seed predation in forest fragments. We evaluated the effects of three microhabitats (gaps, forest edge, and understory) on seed predation of two palm species (Euterpe edulis and Syagrus romanzoffiana) in two semi-deciduous forest fragments (230 and 2100 ha) in southeast Brazil. Our objective was to test two hypotheses: (1) Low rodent abundance in small fragments as a result of meso-predator action levels leads to lower seed predation in small fragments. (2) Most mammal species in small fragments are generalists with respect to diet and habitat, so that seed predation is similar in different microhabitats (gaps, forest edge and understory) in the small fragment, but not in the larger one. The study community of small fragments is usually composed of generalist species (in diet and habitat aspects), so we expected the same rate of seed predation among microhabitats (gaps, forest edge and understory) in the tested smaller fragment. The experiment was carried out in the dry season (for E. edulis) and in the wet season (for S. romanzoffiana) in 1999. We conclude that post-dispersal seed predation in forest fragments can be directly connected with mammal communities, reflecting their historical and ecological aspects.  相似文献   
4.
The Forest and Landscape Restoration movement has emerged as an approach to reconcile biodiversity conservation, ecosystem services provisioning and human well‐being in degraded landscapes, but little is known so far about the potential of different reforestation methods to achieve these objectives. Based on this gap, we assessed the ecological outcomes and local livelihood benefits of community‐managed agroforests and second growth forests to assist natural regeneration in the coastal Atlantic Forest of Brazil. We investigated and compared agroforests and secondary forests according to their structure and floristic composition in 51 circular plots of 314 m², their role in supporting local livelihoods (45 semi‐structured interviews) and the use and cultural importance of plant species (61 interviews). Agroforests and, more remarkably, managed secondary forests (1) re‐established a well‐developed forest structure, with a higher density of tree‐sized individuals and similar basal area compared to nearby old growth forests; (2) were composed by a rich array of native species, including five threatened species, but had lower species richness than old growth remnants; and (3) improved local livelihoods by supplying market valuable and culturally important plants, including 231 native ethnospecies. Overall, local production systems showed remarkable potential to engage smallholders of developing tropical countries in Forest and Landscape Restoration and contribute to achieve its overall goals. We advocate the promotion of these systems as effective Forest and Landscape Restoration approaches in multi‐scale programs and policies.  相似文献   
5.
Summary. Euterpe edulis Martius, a tropical palm species characterized as highly recalcitrant, accumulated dehydrin proteins in both the endosperm and the embryo of the mature seed, as detected by Western blot analysis and immunogold electron microscopy. Three major bands at molecular masses of approximately 16, 18, and 24 kDa were identified in both samples analysed. Immunogold electron microscopy studies detected the presence of dehydrins in the embryo and endosperm. In both cases, dehydrins were immunolocalized in cytoplasm and chromatin. No labelling associated with either membranes or organelles was detected. It is known that dehydrins are produced as part of the developmental program of orthodox seeds and are also present in some recalcitrant seeds of temperate regions. The constitutive presence of dehydrins in embryos of extremely recalcitrant species of tropical origin has not been previously reported. Correspondence and reprints: Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, C1428EHA, Ciudad Autónoma de Buenos Aires, Argentina.  相似文献   
6.
Somatic embryogenesis and further plant regeneration were observed using zygotic embryos, young inflorescences and young leaves ofEuterpe edulis (Palmae) as explants. Both for the cultures of zygotic embryos and inflorescences, activated charcoal in the medium was essential for the establishment of viable cultures. Embryogenesis was induced by using a gelled basal medium with MS or Euwens salts supplemented by high 2, 4-D levels (50–100 mg L−1). The embryogenic process was direct without a callus stage. For further development, cultures with globular or post-globular embryos were transferred to the basal medium with 2-iP (2.5 mg L−1) and NAA (0.1 mg L−1). To convert embryos to plantlets, cultures were transferred to a third medium in which sucrose and salts were reduced to the half-strenght of the basal medium, without growth regulators. In the case of liquid medium, with either 2, 4-D or NAA (10–20 mg L−1). The developmental stage of each explant was critical for the induction of embryogenesis. The histological study of embryogenic cultures revealed that in the case of zygotic embryos, somatic embryos arise directly from the surface of the cotyledonar node, or from subepidermal tissues. In the inflorescences, a pro-embryogenic tissue is formed at the floral primordium region; in the leaves, the first morphogenic event is cell proliferation in the vascular parenchyma.  相似文献   
7.
Large mammalian herbivores play an important role in shaping the diversity of tropical forests by affecting the survival of seedlings and saplings beneath parent plants. The white‐lipped peccary (Tayassu pecari) accounts for the largest herbivore biomass that controls seed and seedling survival in Neotropical ecosystems. However, hunting and habitat loss has driven peccaries to local extinction for most of their original distribution, so it is likely that their absence will affect plant recruitment dynamics. We tested the effects of peccary local extinction on the density and spatial distribution of the hyperdominant palm Euterpe edulis by performing a fine‐scale characterization of its spatial recruitment in six forest sites in the Brazilian Atlantic forest. We compared the age structure and the spatial patterns of seedlings, saplings, and adults as well as the relationship between them. We found that while under the presence of peccaries there was a decrease in recruitment rates under adults, the local extinction of these large mammals led to a more clumped process of spatial recruitment. Despite such contrasting spatial patterns of recruitment dynamics, neither age structure nor the random spatial distribution of adults was affected by the presence or absence of peccaries, indicating that their early effects on these palm populations are mitigated as recruitment advances. Our findings highlight the role of large‐bodied forest‐dwelling herbivores in regulating the fine‐scale spatial recruitment of plants and advance our understanding on the effects of defaunation in tropical forests. Abstract in Portuguese is available with online material.  相似文献   
8.
Euterpe edulis flowers at the beginning of the wet season and fruits over an extended period during the end of the wet season and the dry season. Reproductive plants produced an average of ca 1500 fruits within a season. Five species of birds belonging to the family Turdidae were observed to feed on and disperse the fruits. Most seeds fell directly to the ground, where there was some subsequent local dispersal by water. The dispersion of seeds was highly clumped with most seeds being found in close proximity to adult plants; the distance of dispersal could be described by a negative power curve. Germination was higher on wetter soils. The probability of seedlings advancing to the next size class within a year was inversely related to the density of seedlings, and occurred optimally at ca 4 m from adult plants. The latter observation indicates that the survival and growth of seedlings are suppressed in the immediate vicinity of conspecific adults.  相似文献   
9.
10.
The goal of this study was to examine seasonal frugivory by two sympatric peccary species ( Tayassu pecari and T. tajacu ) in a small (2178 ha), Atlantic Forest fragment on the inland plateau region of São Paulo State, Brazil. Fruit availability was determined with systematic ground surveys conducted over a 5-yr period. Examining fruit availability trends for dry and wet seasons, we found that species diversity was greater in the wet season, but the total number and dry mass of fruits were higher in the dry season. Fruit abundance in the dry season was due to one palm, 'jeriva' ( Syagrus romanzoffiana ), which could be considered a keystone species at Caetetus Ecological Station as it also supported a diverse array of mammals, birds, reptiles, and insects. White-lipped peccaries were the only ungulates that ate palmito fruits ( Euterpe edulis ) at Caetetus. They consumed ripe and unripe fruits and predated the seeds by chewing the pulp and seed. This occurred primarily during the dry season and was associated with a seasonal range shift and a preference for palmito habitat by the white-lipped peccaries. The dominance of fruits in peccary diets (80% fruit items in scat) has management implications for other plateau forest fragments. Forest fragments with diminished fruit abundance or diversity, or lacking key species such as S. romanzoffiana or E. edulis , will not support the energetic requirements of the characteristically large and highly mobile white-lipped peccary populations.  相似文献   
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