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Robert J. Zomer Antonio Trabucco Louis V. Verchot Bart Muys 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):219-239
Within the United Nations Framework Convention on Climate Change (UNFCCC) Kyoto Protocol, countries have significant latitude
to define a forest. The most important parameter affecting area designated as forest is the minimum crown cover which can
be set between 10 and 30%. The choice will have implications for the amount of land available in a country for afforestation
and reforestation activities within the Clean Development Mechanism (CDM-AR). In this paper, we present an analysis of the
regional differences in land availability for CDM-AR projects. We then examine how the choice of a high or low threshold value
for crown cover will affect the area available for CDM activities and how the limitations imposed by this element of the definition
compares to other factors that are likely to limit CDM activities. Results represent a global analysis that included all countries
not included in Annex I of the Kyoto Protocol, and examined the effect on land availability of a range of crown cover thresholds
ranging from 10–30%. Of the 140 Non-Annex One countries, 107 countries were found to have a potential for CDM-AR projects.
Asia had the largest amount of combined area suitable for CDM-AR at the 10% crown cover threshold level. However, at 30%,
South America had the greatest amount of land available, and a large change in available land area, which increased by almost
five times compared to what was available at the 10% threshold. The area available in Africa increased by a factor of 5.5.
Central America showed the largest increase, to almost 10 times more at the 30% threshold. By contrast, within Asia, the area
increase was comparatively less, but still the area nearly doubled. Globally, a low threshold of 10% crown cover excluded
almost 2/3 of the land identified that was eligible at 30%, over 5 million km2. The spatial analyses showed not only the effects of the choice of the crown cover criterion, but also where the land was
available for CDM activities within each country at different thresholds. Protected areas account for 10–20% of the CDM-AR
eligible area in most countries. 相似文献
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Daniela Turchetti Elisabetta Razzaboni Hila Zomer Cesare Rossi Simona Ferrari Donatella Greco Claudio Graziano Giovanni Romeo Marco Seri 《黑龙江环境通报》2006,26(12):1156-1159
Angelman Syndrome (AS), characterized by mental retardation, absence of speech, seizures and motor dysfunction, is caused by genetic defects leading to loss of expression of the maternal copy of the chromosome 15q11–13 imprinted region. Most cases are sporadic, being caused by de novo deletion of maternal chromosome 15q11–13 (75%) or by paternal uniparental disomy (3–4%). Familial cases can occur, due to mutations in the UBE3A gene or in the imprinting center. We describe the case of a pregnant woman having two nephews with AS caused by a UBE3A mutation; lack of communication within the family led the woman to be completely unaware of the risk of disease recurrence until 15 weeks of gestation. UBE3A genetic testing revealed she carried the familial mutation 892–893delCT. Prenatal diagnosis was performed on amniotic fluid and demonstrated that the fetus had inherited the mutation. The unexpected diagnosis and the subsequent termination of the pregnancy caused the woman to undergo acute psychological distress showing relevant psychopathological symptoms. Nevertheless, at 2-year follow-up, adverse consequences were minimized, and the couple was planning a new pregnancy. Factors affecting the psychological outcome of abortion and the role of psychological support in reducing the risk of long-term unfavorable consequences are discussed. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Building spectral libraries for wetlands land cover classification and hyperspectral remote sensing 总被引:3,自引:0,他引:3
Recent advances in remote sensing provide opportunities to map plant species and vegetation within wetlands at management relevant scales and resolutions. Hyperspectral imagers, currently available on airborne platforms, provide increased spectral resolution over existing space-based sensors that can document detailed information on the distribution of vegetation community types, and sometimes species. Development of spectral libraries of wetland species is a key component needed to facilitate advanced analytical techniques to monitor wetlands. Canopy and leaf spectra at five sites in California, Texas, and Mississippi were sampled to create a common spectral library for mapping wetlands from remotely sensed data. An extensive library of spectra (n=1336) for coastal wetland communities, across a range of bioclimatic, edaphic, and disturbance conditions were measured. The wetland spectral libraries were used to classify and delineate vegetation at a separate location, the Pacheco Creek wetland in the Sacramento Delta, California, using a PROBE-1 airborne hyperspectral data set (5m pixel resolution, 128 bands). This study discusses sampling and collection methodologies for building libraries, and illustrates the potential of advanced sensors to map wetland composition. The importance of developing comprehensive wetland spectral libraries, across diverse ecosystems is highlighted. In tandem with improved analytical tools these libraries provide a physical basis for interpretation that is less subject to conditions of specific data sets. To facilitate a global approach to the application of hyperspectral imagers to mapping wetlands, we suggest that criteria for and compilation of wetland spectral libraries should proceed today in anticipation of the wider availability and eventual space-based deployment of advanced hyperspectral high spatial resolution sensors. 相似文献
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