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311.
The objectives of Habitat II were (1) in the long term to arrest the deterioration of human settlements and create the conditions to achieve improvement in the environment on a sustainable basis, and (2) to adopt a general statement on principles and related Global Action Plan to guide national and international efforts in the next two decades. We have asked the Mayor of Curitiba, Brazil Rafael Greca de Macedo to comment on the conference results. Curitiba is one of the most known example of urban ecological planning. 相似文献
312.
María Elizabeth Barroeta-Hlusicka Joaquín Buitrago Martín Rada Ricardo Pérez 《Journal of Coastal Conservation》2012,16(1):65-76
Protected areas are the core of efforts to conserve biological diversity and zoning uses, and they are used as a tool for
their management. Global Positioning Systems (GPS) and Geographic Information System (GIS) have been used to evaluate conflicts
between approved uses and actual uses in La Restinga Lagoon National Park in Venezuela (LRLNP). The park (188.6 km2), covers various ecosystems such as coastal lagoons, marine waters and xerophytic vegetation, it is visited by up to 260,000
people visit per year. A GIS, using a base map compiled from 1:25,000 maps was developed. Natural cover was mapped from LANDSAT
VII TM images, orthophotomaps and aerial photographs. Spatial use data was collected by field GPS location of any use inside
the park during 2 years. Thematic vector maps for each land cover, zoning area, and observed use were created. Maps of zoning
and uses were overlapped and new maps for each use-zoning crossing were created. The park contain nine different zoning areas
wherein 28 different uses were identified, 18 of them were direct consumptive and non-consumptive uses, occurring on 54% of
the park. Tourism transit areas were the most used zones. More than 5,000 people use the park during a high season day. Superimposition
of zoning maps with actual use data produced 13 uses taking place in not allowed areas (46% of park area). Most common prohibited
use was commercial net fishing, occurring in nearly 40% of the park area. Therefore, identifying human use conflicts and its
geographical distribution is a key issue to improve Management Plans as well as identifying hot sites. The GPS-GIS methodology
presented here allows Park Rangers to select those areas which could benefit from enhanced supervision with the limited budget
available. 相似文献
313.
The nurse shark, Ginglymostoma cirratum, inhabits shallow, tropical, and subtropical waters in the Atlantic and the eastern Pacific. Unlike many other species of
sharks, nurse sharks are remarkably sedentary. We assayed the mitochondrial control region and eight microsatellite loci from
individuals collected primarily in the western Atlantic to estimate the degree of population subdivision. Two individuals
from the eastern Atlantic and one from the Pacific coast of Panama also were genotyped. Overall, the mtDNA haplotype (h = 48 ± 5%) and nucleotide (π = 0.08 ± 0.06%) diversities were low. The microsatellite data mirror the mitochondrial results
with the average number of alleles ([`(N)]A \bar{N}_{A} = 9) and observed heterozygosity ([`(H)]O \bar{H}_{O} = 0.58) both low. The low levels of diversity seen in both the mtDNA and the microsatellite may be due to historical sea
level fluctuations and concomitant loss of shallow water habitat. Eight of the 10 pair-wise western Atlantic F
ST estimates for mtDNA indicated significant genetic subdivision. Pair-wise F
ST values for the microsatellite loci indicated a similar pattern as the mtDNA. The western Atlantic population of nurse sharks
is genetically subdivided with the strongest separation seen between the offshore islands and mainland Brazil, likely due
to deep water acting as a barrier to dispersal. The eastern and western Atlantic populations were closely related. The eastern
Pacific individual is quite different from Atlantic individuals and may be a cryptic, sister species. 相似文献
314.
Carolina Briones Ricardo Gui?ez Orlando Garrido Pablo A. Oyarzún Jorge E. Toro Montse Pérez 《Marine Biology》2012,159(8):1865-1870
For the first time in a marine bivalve species, geographic intraspecific variation in sperm morphology in the Chilean mussel, Perumytilus purpuratus, is reported. Samples were obtained in December 2010 from the rocky intertidal at three locations: Antofagasta (23o44′01.08′′S, 70o26′26.11′′W), Valparaíso (32o57′23.07′′S, 71o33′01.86′′W), and Valdivia (39°50′44.26′′S, 73°25′51.99′′W). Scanning electron microscopy was used to describe sperm traits, and genetic data were obtained by sequencing a 16S mtDNA 427-bp fragment. The results showed geographic intraspecific variation with two statistically significant patterns of genetically differentiated sperm morphologies. One genetic clade was found for Antofagasta and Valparaíso, displaying a unique sperm morphotype with a short acrosome accounting for 26 % of the head length, and the other from Valdivia, with a larger acrosome occupying 47 % of the head length. These results will lead to new research to distinguish among alternative hypotheses: the presence of cryptic species, incipient speciation, or a polymorphism in sperm traits of P. purpuratus. 相似文献
315.
Polybrominated diphenyl ethers (PBDEs) have become an issue of global concern. Recent studies have shown that farmed salmon can accumulate high levels of brominated compounds in their tissues and consequently there is a growing concern on its industrial and public health impacts. Little information is found in the international literature on PBDEs in the biotic compartment of the Southern Hemisphere. This paper reports the levels of several PBDE congeners found in the tissues of farmed fish from five different farming areas of Southern Chile. PBDEs were analyzed by HRGC-MS. More analytical data were obtained by analyzing these same pollutants in fish feed. Our results indicate a general trend of PBDE levels averaging 1.46 ng g(-1) wet weight (wwt). The observed congeneric distribution that resulted was quite similar to data previously reported in the open literature. PBDE profiles were found to be dominated by BDE 47. No correlation was observed between levels found in the tissues and the lipid content in such tissues, although a high correlation with the fish feed data was observed indicating that this could probably be the main PDBE entry source into fish, although other sources cannot be excluded. Even though the samples were obtained from different geographical areas, they presented fairly similar profiles, indicating a potential common source. We concluded that PBDE levels in the farmed Chilean salmon are in the low average range of values published in the open literature. 相似文献
316.
Gerard F. Ricardo Andrew R. Davis Nathan A. Knott Todd E. Minchinton 《Marine Biology》2014,161(4):769-784
Variation in the release and recruitment of larvae of estuarine invertebrates affects the distribution and abundance of adults, as well as trophic interactions in both the plankton and the benthos. Larval release and supply are often timed to environmental cycles such as the diel and tidal cycles. Here, we determined using plankton tows whether the abundance of larvae spanning salt marsh and mangrove habitats across the intertidal landscape varied with diel and tidal cycles. Using three different sampling designs across two sites and within each of two estuaries over a 12-month period, we covered a range of spatial and temporal scales. This allowed us to test the general prediction that densities of meroplankton in the water column would be greater during nocturnal ebb tides than during other phases of the diel or tidal cycle. As predicted, nocturnal ebb tides yielded the highest densities of meroplanktonic larvae and were dominated by first-stage crab zoeae and this finding was most pronounced in the salt marsh. Throughout the course of the year, greater numbers of meroplankters consistently occurred during the ebb tide compared with the flood tide. The densities of other taxa (e.g. gastropods and polychaetes) showed no clear trends with diel or tidal cycles. This study highlights the effects of these pervasive physical cycles on the timing of larval release and supply in the salt marsh–mangrove complex, and emphasises their contribution to the trophic interactions and the dynamics of benthic populations within estuaries. 相似文献
317.
Rafael Grossi Botelho Valdemar Luis Tornisielo Ricardo Alves de Olinda Lucineide Aparecida Maranho Luís Machado-Neto 《毒物与环境化学》2013,95(10):2035-2045
The purpose of this study was to investigate the toxicity of vinasse to cladocerans and fish before and after pH adjustment using an acute toxicity test. Linear and quadratic regression models were adjusted to demonstrate the concentration–response relationship between vinasse and the endpoints evaluated. The median lethal concentrations (LC50–48h) of vinasse before pH adjustment for Ceriodaphnia dubia and Daphnia magna were 0.67% and 0.80% respectively, and the median lethal concentrations (LC50–96h) for Danio rerio was 2.62%. After pH adjustment, the values increased for all organisms, demonstrating a decrease in toxicity. This study reported marked toxicity for vinasse to aquatic organisms with toxicity reduction after pH adjustment. 相似文献
318.
Silveira Miranda Jefferson Eduardo de Melo Fabiano Rodrigues Keichi Umetsu Ricardo 《Environmental management》2020,65(4):565-573
Environmental Management - Understand the spatial distribution of wildlife roadkill is necessary to design mitigation measures minimizing damage to the fauna and the human population. Thus, we... 相似文献
319.
Solano Ricardo Patiño-Ruiz David Tejeda-Benitez Lesly Herrera Adriana 《Environmental science and pollution research international》2021,28(14):16962-16981
Environmental Science and Pollution Research - The production and demand of nanoparticles in the manufacturing sector and personal care products, release a large number of engineered nanoparticles... 相似文献