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1.
国际森林认证与我国野生森林产品开发 总被引:1,自引:0,他引:1
世界森林认证发展迅速.目前认证体系可以分为全球、地区和国家三个层次.我国政府森林认证立法起步较晚,挑战和机遇并存.森林认证包括林场管理、产销供应链和非森林木材产品认证,其中后者对我国森林认证具有深远的意义.结合世界森林认证体系发展历程和我国具体国情,对我国开发非木材林产品提出了建议. 相似文献
2.
Regulatory enforcement of forest conservation laws is often dismissed as an ineffective approach to reducing tropical forest loss. Yet, effective enforcement is often a precondition for alternative conservation measures, such as payments for environmental services, to achieve desired outcomes. Fair and efficient policies to reducing emissions from deforestation and forest degradation (REDD) will thus crucially depend on understanding the determinants and requirements of enforcement effectiveness. Among potential REDD candidate countries, Brazil is considered to possess the most advanced deforestation monitoring and enforcement infrastructure. This study explores a unique dataset of over 15 thousand point coordinates of enforcement missions in the Brazilian Amazon during 2009 and 2010, after major reductions of deforestation in the region. We study whether local deforestation patterns have been affected by field-based enforcement and to what extent these effects vary across administrative boundaries. Spatial matching and regression techniques are applied at different spatial resolutions. We find that field-based enforcement operations have not been universally effective in deterring deforestation during our observation period. Inspections have been most effective in reducing large-scale deforestation in the states of Mato Grosso and Pará, where average conservation effects were 4.0 and 9.9 hectares per inspection, respectively. Despite regional and actor-specific heterogeneity in inspection effectiveness, field-based law enforcement is highly cost-effective on average and might be enhanced by closer collaboration between national and state-level authorities. 相似文献
3.
Laura Castro-Diaz Maria Claudia Lopez Emilio Moran 《Human ecology: an interdisciplinary journal》2018,46(3):411-422
The Belo Monte Hydroelectric dam on the Xingu River in the Brazilian Amazon will be the third largest dam in the world in power generating capacity (11 GW). Its construction has brought negative socioeconomic and environmental impacts for local fishers that far outweigh the benefits. We used a qualitative case study approach to explore perceptions among fishers in a community downstream from the dam of the impact of Belo Monte on their livelihoods and their fisheries. We found that fishers, who, although they were not displaced were neither consulted nor compensated, have been severely impacted by the dam, and that fishermen and fisherwomen are differentially affected. More attention needs to be given to downstream communities and the impacts they experience. 相似文献
4.
Leandro Da Silva Duarte Rodrigo Scarton Bergamin Vinícius Marcilio-Silva Guilherme Dubal Dos Santos Seger Márcia Cristina Mendes Marques 《PloS one》2014,9(8)
Phylobetadiversity is defined as the phylogenetic resemblance between communities or biomes. Analyzing phylobetadiversity patterns among different vegetation physiognomies within a single biome is crucial to understand the historical affinities between them. Based on the widely accepted idea that different forest physiognomies within the Southern Brazilian Atlantic Forest constitute different facies of a single biome, we hypothesize that more recent phylogenetic nodes should drive phylobetadiversity gradients between the different forest types within the Atlantic Forest, as the phylogenetic divergence among those forest types is biogeographically recent. We compiled information from 206 checklists describing the occurrence of shrub/tree species across three different forest physiognomies within the Southern Brazilian Atlantic Forest (Dense, Mixed and Seasonal forests). We analyzed intra-site phylogenetic structure (phylogenetic diversity, net relatedness index and nearest taxon index) and phylobetadiversity between plots located at different forest types, using five different methods differing in sensitivity to either basal or terminal nodes (phylogenetic fuzzy weighting, COMDIST, COMDISTNT, UniFrac and Rao’s H). Mixed forests showed higher phylogenetic diversity and overdispersion than the other forest types. Furthermore, all forest types differed from each other in relation phylobetadiversity patterns, particularly when phylobetadiversity methods more sensitive to terminal nodes were employed. Mixed forests tended to show higher phylogenetic differentiation to Dense and Seasonal forests than these latter from each other. The higher phylogenetic diversity and phylobetadiversity levels found in Mixed forests when compared to the others likely result from the biogeographical origin of several taxa occurring in these forests. On one hand, Mixed forests shelter several temperate taxa, like the conifers Araucaria and Podocarpus. On the other hand, tropical groups, like Myrtaceae, are also very representative of this forest type. We point out to the need of more attention to Mixed forests as a conservation target within the Brazilian Atlantic Forest given their high phylogenetic uniqueness. 相似文献
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Gabriela Bielefeld Nardoto Jean Pierre Henry Balbaud Ometto James R. Ehleringer Niro Higuchi Mercedes Maria da Cunha Bustamante Luiz Antonio Martinelli 《Ecosystems》2008,11(8):1234-1246
Nitrogen variations at different spatial scales and integrated across functional groups were addressed for lowland tropical
forests in the Brazilian Amazon as follows: (1) how does N availability vary across the region over different spatial scales
(regional × landscape scale); (2) how are these variations in N availability integrated across plant functional groups (legume × non-legume
trees). Leaf N, P, and Ca concentrations as well the leaf N isotope ratios (δ15N) from a large set of legume and non-legume tree species were measured. Legumes had higher foliar N/Ca ratios than non-legumes,
consistent with the high energetic costs in plant growth associated with higher foliar P/Ca ratios found in legumes than in
non-legumes. At the regional level, foliar δ15N decreased with increasing rainfall. At the landscape level, N availability was higher in the forests on clayey soils on
the plateau than in forests on sandier soils. The isotope as well as the non-isotope data relationships here documented, explain
to a large extent the variation in δ15N signatures across gradients of rainfall and soil. Although at the regional level, the precipitation regime is a major determinant
of differences in N availability, at the landscape level, under the same precipitation regime, soil type seems to be a major
factor influencing the availability of N in the Brazilian Amazon forest. 相似文献
6.
Regenerating forests have become a common land-cover type throughout the Brazilian Amazon. However, the potential for these systems to accumulate and store C and nutrients, and the fluxes resulting from them when they are cut, burned, and converted back to croplands and pastures have not been well quantified. In this study, we quantified pre- and post-fire pools of biomass, C, and nutrients, as well as the emissions of those elements, at a series of second- and third-growth forests located in the states of Pará and Rondônia, Brazil. Total aboveground biomass (TAGB) of second- and third-growth forests averaged 134 and 91 Mg ha–1, respectively. Rates of aboveground biomass accumulation were rapid in these systems, but were not significantly different between second- and third-growth forests, ranging from 9 to 16 Mg ha–1 year–1. Residual pools of biomass originating from primary forest vegetation accounted for large portions of TAGB in both forest types and were primarily responsible for TAGB differences between the two forest types. In second-growth forests this pool (82 Mg ha–1) represented 58% of TAGB, and in third-growth forests (40 Mg ha–1) it represented 40% of TAGB. Amounts of TAGB consumed by burning of second- and third-growth forests averaged 70 and 53 Mg ha–1, respectively. Aboveground pre-fire pools in second- and third-growth forests averaged 67 and 45 Mg C ha–1, 821 and 707 kg N ha–1, 441 and 341 kg P ha–1, and 46 and 27 kg Ca ha–1, respectively. While pre-fire pools of C, N, S and K were not significantly different between second- and third-growth forests, pools of both P and Ca were significantly higher in second-growth forests. This suggests that increasing land use has a negative impact on these elemental pools. Site losses of elements resulting from slashing and burning these sites were highly variable: losses of C ranged from 20 to 47 Mg ha–1; N losses ranged from 306 to 709 kg ha–1; Ca losses ranged from 10 to 145 kg ha–1; and P losses ranged from 2 to 20 kg ha–1. Elemental losses were controlled to a large extent by the relative distribution of elemental mass within biomass components of varying susceptibilities to combustion and the temperatures of volatilization of each element. Due to a relatively low temperature of volatilization and its concentration in highly combustible biomass pools, site losses of N averaged 70% of total pre-fire pools. In contrast, site losses of P and Ca resulting from burning were 33 and 20% of total pre-fire pools, respectively, as much of the mass of those elements was deposited on site as ash. Pre- and post-fire biomass and elemental pools of second- and third-growth forests, as well as the emissions from those systems, were intermediate between those of primary forests and pastures in the Brazilian Amazon. Overall, regenerating forests have the capacity to act as either large terrestrial sinks or sources of C and nutrients, depending on the course of land-use patterns within the Brazilian Amazon. Combining remote sensing techniques with field measures of aboveground C accumulation in regenerating forests and C fluxes from those forests when they are cut and burned, we estimate that during 1990–1991 roughly 104 Tg of C was accumulated by regenerating forests across the Brazilian Amazon. Further, we estimate that approximately 103 Tg of C was lost via the cutting and burning of regenerating forests across the Brazilian Amazon during this same period. Since average C accumulations (5.5 Mg ha–1 year–1) in regenerating forests were 19% of the C lost when such forests are cut and burned (29.3 Mg ha–1), our results suggest that when less than 19% of the total area accounted for by secondary forests is cut and burned in a given year, those forests will be net accumulators of C during that year. Conversely, when more than 19% of regenerating forests are burned, those forests will be a net source of C to the atmosphere. 相似文献
7.
Impacts of Cash Transfer Programs on Rural Livelihoods: a Case Study in the Brazilian Amazon Estuary
Yue Dou Peter Deadman Derek Robinson Oriana Almeida Sergio Rivero Nathan Vogt Miguel Pinedo-Vasquez 《Human ecology: an interdisciplinary journal》2017,45(5):697-710
We conducted a large household survey in a region of the Amazon estuary in Brazil to investigate the dependence of small farming households on government cash transfers and to identify the main factors that lead to better livelihood outcomes. The study examined the factors that contribute to heterogeneous household livelihoods and patterns of dependence on cash transfer programs. Multinomial logistic regression was used to evaluate household attributes affecting the level of dependence on cash transfers. Results indicate that households engage in a diversity of livelihood strategies, and vary in dependence on cash transfers. Lower levels of dependency are associated with higher levels of education and income from off-farm activities as well as larger property sizes and holdings in the várzea. Recognition of the causes and potential range of dependence on cash transfer programs adds decision-making capacity for policy makers seeking avenues to reduce dependence and increase program effectiveness. 相似文献
8.
Silvana Gomes Benzecry Márcia Almeida Alexandre Sheila Vítor-Silva Jorge Luis Salinas Gisely Cardoso de Melo Helyde Albuquerque Marinho ?ngela Tavares Paes André Machado de Siqueira Wuelton Marcelo Monteiro Marcus Vinícius Guimar?es Lacerda Heitor Pons Leite 《PloS one》2016,11(3)
Background
There is a growing body of evidence linking micronutrient deficiencies and malaria incidence arising mostly from P. falciparum endemic areas. We assessed the impact of micronutrient deficiencies on malaria incidence and vice versa in the Brazilian state of Amazonas.Methodology/Principal Findings
We evaluated children <10 years old living in rural communities in the state of Amazonas, Brazil, from May 2010 to May 2011. All children were assessed for sociodemographic, anthropometric and laboratory parameters, including vitamin A, beta-carotene, zinc and iron serum levels at the beginning of the study (May 2010) and one year later (May 2011). Children were followed in between using passive surveillance for detection of symptomatic malaria. Those living in the study area at the completion of the observation period were reassessed for micronutrient levels. Univariate Cox-proportional Hazards models were used to assess whether micronutrient deficiencies had an impact on time to first P. vivax malaria episode. We included 95 children median age 4.8 years (interquartile range [IQR]: 2.3–6.6), mostly males (60.0%) and with high maternal illiteracy (72.6%). Vitamin A deficiencies were found in 36% of children, beta-carotene deficiency in 63%, zinc deficiency in 61% and iron deficiency in 51%. Most children (80%) had at least one intestinal parasite. During follow-up, 16 cases of vivax malaria were diagnosed amongst 13 individuals. Micronutrient deficiencies were not associated with increased malaria incidence: vitamin A deficiency [Hazard ratio (HR): 1.51; P-value: 0.45]; beta-carotene [HR: 0.47; P-value: 0.19]; zinc [HR: 1.41; P-value: 0.57] and iron [HR: 2.31; P-value: 0.16]). Upon reevaluation, children with al least one episode of malaria did not present significant changes in micronutrient levels.Conclusion
Micronutrient serum levels were not associated with a higher malaria incidence nor the malaria episode influenced micronutrient levels. Future studies targeting larger populations to assess micronutrients levels in P. vivax endemic areas are warranted in order to validate these results. 相似文献9.
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In closed‐canopy tropical forest understory, light availability is a significant determinant of habitat diversity because canopy structure is highly variable in most tropical forests. Consequently, variation in canopy cover affects the composition and distribution of plant species via creating variable light environments. Nevertheless, little is known about how variation in canopy openness structures patterns of plant–animal interactions. Because of the great diversity and dominance of ants in tropical environments, we used ant–plant interactions as a focal network to evaluate how variation in canopy cover influences patterns of plant–insect interactions in the Brazilian Amazon rain forest. We observed that small increases in canopy openness are associated with increased diversity of ant–plant interactions in our study area, and this change is independent of plant or ant species richness. Additionally, we found smaller niche overlap for both ants and plants associated with greater canopy openness. We hypothesize that enhanced light availability increases the breadth of ant foraging sources because variation in light availability gives rise to plant resources of different quality and amounts. Moreover, greater light availability promotes vegetative growth in plants, creating ant foraging ‘bridges’ between plants. In sum, our results highlight the importance of environmental heterogeneity as a determinant of ant–plant interaction diversity in tropical environments. 相似文献
12.
The analysis of biologic variation in prehistoric human populations separately by sex has been used as a tool to recover post-marital residential rules. These studies, which focus on the sexual distribution of skeletal traits, assume that the degree of intragroup or intergroup biologic diversity is higher in one sex with regard to unilocality (uxori- or virilocality). Despite a recent attempt to interpret this phenomenon in terms of population genetics (Konigsberg 1988), the main assumption has never been tested in situations in which the real residential practice of an indigenous population is known and in which genetic rather than phenotypic data are available. We investigated the within-group and between-group genetic variability among males and females from 4 villages of an uxorilocal Amazonian tribe, the Urubu-Ka'apor, on the basis of 20 polymorphic loci. The results were only partly concordant with the expected. Individual mean per locus heterozygosities were not different between the sexes, and the analysis of genetic heterogeneity showed similar gene frequencies for males and females in all villages. On the other hand, the intergroup approach detected a level of variation significantly greater among females than among males. The ethnographic evidence shows that three of the four subgroups studied belong to the same gamic unity, with the fourth subgroup belonging to another gamic network. Within-sex differences in intergroup analysis turned out to be more evident; yet, when those 3 villages were investigated separately, the female FST (0.0609) proved to be significantly higher than the male FST (0.0218). Such results suggest that the intergroup analysis is more sensitive to the genetic effects of differential migration rates between the sexes. In prehistoric contexts, therefore, an intergroup genetic approach can provide more reliable grounds for sociocultural inferences. 相似文献
13.
Deforestation and land use in the Brazilian Amazon 总被引:4,自引:0,他引:4
Emilio F. Moran 《Human ecology: an interdisciplinary journal》1993,21(1):1-21
Deforestation in the Brazilian Amazon was less than 1% before 1975. Between 1975 and 1987 the rate increased exponentially. By 1985, world opinion and attention to the destruction of the richest biome on earth led to elimination of some of the major incentives that had fueled deforestation. Favorable credit policies for cattle ranchers, rather than population growth, explains the process of deforestation in the Brazilian Amazon. The paper suggests other actions that may be taken to reduce deforestation, and examines the rapid growth rates of secondary successional species in a colonization area. 相似文献
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Tropical forests are diminishing in extent due primarily to the rapid expansion of agriculture, but the future magnitude and geographical distribution of future tropical deforestation is uncertain. Here, we introduce a dynamic and spatially-explicit model of deforestation that predicts the potential magnitude and spatial pattern of Amazon deforestation. Our model differs from previous models in three ways: (1) it is probabilistic and quantifies uncertainty around predictions and parameters; (2) the overall deforestation rate emerges “bottom up”, as the sum of local-scale deforestation driven by local processes; and (3) deforestation is contagious, such that local deforestation rate increases through time if adjacent locations are deforested. For the scenarios evaluated–pre- and post-PPCDAM (“Plano de Ação para Proteção e Controle do Desmatamento na Amazônia”)–the parameter estimates confirmed that forests near roads and already deforested areas are significantly more likely to be deforested in the near future and less likely in protected areas. Validation tests showed that our model correctly predicted the magnitude and spatial pattern of deforestation that accumulates over time, but that there is very high uncertainty surrounding the exact sequence in which pixels are deforested. The model predicts that under pre-PPCDAM (assuming no change in parameter values due to, for example, changes in government policy), annual deforestation rates would halve between 2050 compared to 2002, although this partly reflects reliance on a static map of the road network. Consistent with other models, under the pre-PPCDAM scenario, states in the south and east of the Brazilian Amazon have a high predicted probability of losing nearly all forest outside of protected areas by 2050. This pattern is less strong in the post-PPCDAM scenario. Contagious spread along roads and through areas lacking formal protection could allow deforestation to reach the core, which is currently experiencing low deforestation rates due to its isolation. 相似文献
17.
Walter Santos de Araújo Kleber do Espírito-Santo Filho 《Biodiversity and Conservation》2012,21(11):2991-2997
We investigated the influence of edge effects on communities of galling insects in the Brazilian Amazon. For this, were performed data analyses comparing the galling richness between disturbed and undisturbed areas, and subsequently evaluated the richness of galling at different distances from the forest edge. We registered 194 galling insect morphotypes in 116 host plant species. Galling insect richness was more pronounced in disturbed areas and closer to the forest edge, both to community in general as to specific host plant taxa. These results indicate positive responses of galling insect richness to edge effects in forest environments. Edge effect could influence the galling distribution in modified habitats because increases the stress conditions of the plants and decreases the attack pressure of natural enemies. 相似文献
18.
Hepatitis B and C virus markers were assessed during a survey on malaria in gold mine camps in southern Brazilian Amazon in order to identify risk factors associated to these viral diseases. The study comprised 520 subjects, most of them were gold miners. Missing subjects totaled 49 (8.6%). Among these 520, 82.9% had HBV markers and 7.1% were HBsAg positive. Previous hospitalization, surgery, sexually transmitted diseases and incarceration were quite common among surveyed people, but there is no association between total HBV markers and these factors. On other hand, HBsAg was independently associated to history of sexually transmitted diseases and history of surgery after adjustment. The most frequent HBsAg subtypes identified, adw2 (59%), predominates in populations of Northeast Brazil. The most surveyed people were immigrants coming from that area suggesting that immigrants carried HBV themselves to the study area. Immunoblot (RIBA) confirmed-anti-HCV were found in 2.1%. The only variable associated to anti-HCV in multivariate analysis was illicit intravenous drug. Lack of HCV infection in subjects with such a high HBV markers prevalence reinforces the opinion that HCV is transmitted by restricted routes when compared to HBV. Furthermore, gold miners in Amazon may be considered as a risk group for HBV infection, but not for HCV. 相似文献
19.
Restoration of Tropical Moist Forests on Bauxite-Mined Lands in the Brazilian Amazon 总被引:2,自引:1,他引:2
We evaluated forest structure and composition in 9- to 13-year-old stands established on a bauxite-mined site at Trombetas (Pará), Brazil, using four different reforestation techniques following initial site preparation and topsoil replacement. These techniques included reliance on natural forest regeneration, mixed commercial species plantings of mostly exotic timber trees, direct seeding with mostly native early successional tree species, and mixed native species plantings of more than 70 tree species (the current operational restoration treatment at this site). Replicated fixed-radius plots in each treatment and in undisturbed primary forest were used to quantify the canopy and understory structure and the abundance and diversity of all vascular plant species. Treatment comparisons considered regeneration density, species richness and diversity for all floristic categories, and, for trees and shrubs, the relative contribution of initial planting and subsequent regeneration from soil seed banks and seed inputs from nearby primary forests. With the possible exception of the stands of mixed commercial species, which were superior to all others in terms of tree basal-area development but relatively poor in species richness, all treatments were structurally and floristically diverse, with a high probability of long-term restoration success. Of these, the mixed native species plantings appeared to be at least risk of arrested succession due to the dominance of a broader range of tree species of different successional stages or expected life spans. In all treatments, several locally important families of primary forest trees (Annonaceae, Chrysobalanaceae, Lauraceae, Palmae and Sapotaceae) were markedly underrepresented due to a combination of poor survival of initial plantings and limitations on seed dispersal from the surrounding primary forest. 相似文献