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81.
The Effectiveness of Contrasting Protected Areas in Preventing Deforestation in Madre de Dios, Peru 总被引:1,自引:1,他引:0
Accurate monitoring of the effectiveness of protected areas (PAs) in decreasing deforestation is increasingly important given the vital role of forest protection in climate change mitigation. Recent studies on PA effectiveness have used remote-sensing imagery to compare deforestation rates within PAs to surrounding areas. However, remote-sensing data used in isolation provides limited information on the factors contributing to effectiveness. We used landscape-modelling techniques to estimate the effectiveness of ten PAs in Madre de Dios, Peru. Factors influencing PA effectiveness were investigated using in situ key-informant interviews. Although all of the PAs studied had positive effectiveness scores, those with the highest scores were ecotourism and conservation concessions, where monitoring and surveillance activities and good relations with surrounding communities were reported as possible factors in decreasing deforestation rates. Native community areas had the lowest scores, with deforestation mainly driven by internal resource use and population growth. Weak local governance and immigration were identified as underlying factors decreasing the effectiveness of protection, whereas good relations with surrounding communities and monitoring activity increased effectiveness. The results highlight the need to combine remote sensing with in situ information on PA management because identification of drivers and deterrents of deforestation is vital for improving the effectiveness of protection. 相似文献
82.
Stomatal characteristics and infection biology of Pyrenopeziza betulicola in Betula pendula trees grown under elevated CO2 and O3 总被引:2,自引:0,他引:2
Riikonen J Syrjälä L Tulva I Mänd P Oksanen E Poteri M Vapaavuori E 《Environmental pollution (Barking, Essex : 1987)》2008,156(2):536-543
Two silver birch clones were exposed to ambient and elevated concentrations of CO2 and O3, and their combination for 3 years, using open-top chambers. We evaluated the effects of elevated CO2 and O3 on stomatal conductance (gs), density (SD) and index (SI), length of the guard cells, and epidermal cell size and number, with respect to crown position and leaf type. The relationship between the infection biology of the fungus (Pyrenopeziza betulicola) causing leaf spot disease and stomatal characteristics was also studied. Leaf type was an important determinant of O3 response in silver birch, while crown position and clone played only a minor role. Elevated CO2 reduced the gs, but had otherwise no significant effect on the parameters studied. No significant interactions between elevated CO2 and O3 were found. The infection biology of P. betulicola was not correlated with SD or gs, but it did occasionally correlate positively with the length of the guard cells. 相似文献
83.
Tanja Eybe Jean-Nicolas Audinot Thomas Udelhoven Esther Lentzen Brahime El Adib Johanna Ziebel Lucien Hoffmann Torsten Bohn 《Chemosphere》2013,90(6):1829-1838
Environmental heavy metal contamination is a case of concern for both animal and human health. Studying the fate of metals in plant or animal tissues may provide information on pollution. In the present study, we investigated the possibility to follow the biological fate of chromium and platinum uptake in common garden snails (Helix aspersa), typically accumulating high concentrations of metals from their environment. Chromium and platinum were administered orally to snails in 5 groups (n = 25/group): control, food contaminated by ca. 2.5 μg g?1 and 19 μg g?1 chromium and 2.5 μg g?1 and 25 μg g?1 platinum, for 8 weeks. Following exposure, surviving snails were sacrificed, shell and remaining tissue investigated by ICP-MS, and shell, midgut gland and mantle by nano-secondary ion mass-spectrometry (Nano-SIMS). 12C14N-normalized platinum and 40Ca-normalized chromium measurements indicated highest enrichments in cellular vesicles of the midgut gland, and lower concentrations in mantle and shell, with significantly higher platinum and chromium concentrations in the 2 exposure groups vs. control (P < 0.05), with somewhat differing distribution patterns for chromium and platinum. Comparable results were obtained by ICP-MS, with both chromium and platinum fed snails showing drastically elevated concentrations of metals in shell (up to 78 and 122 μg g?1 dw platinum and chromium, respectively) and in other tissues (up to 200 and 1125 μg g?1 dw platinum and chromium, respectively). Nano-SIMS allowed for semi-quantitative comparison of metal fate in snail tissues, making this an interesting technique for future studies in the area of environmental pollution. 相似文献
84.
Johanna?Chemnitz Nadiia?Bagrii Manfred?Ayasse Sandra?SteigerEmail author 《Die Naturwissenschaften》2017,104(7-8):53
Life history theory predicts a trade-off between male sexual trait expression and immunocompetence. Using burying beetles, Nicrophorus vespilloides, as a model, we investigated the relationship between male immune function, sex pheromone emission, and attractiveness under field conditions. In the first experiment, we tested whether there is a positive correlation between immune capacity, sex pheromone characteristics (quantity, relative composition, and time invested in pheromone emission), and male attractiveness. As a measurement of immune capacity, we used an individual’s encapsulation ability against a novel antigen. In the second experiment, we specifically examined whether a trade-off between chemical trait expression and immune function existed. To this end, we challenged the immune system and measured the subsequent investment in sex pheromone emission and the attractiveness of the male under field conditions. We found that a male’s immunocompetence was neither related to the emission of the male’s sex pheromone nor to its attractiveness in the field. Furthermore, none of the immune-challenge treatments affected the subsequent investment in pheromone emission or number of females attracted. However, we showed that the same males that emitted a high quantity of their sex pheromone in the laboratory were able to attract more females in the field. Our data suggest that the chemical signal is not a reliable predictor of a male’s immunocompetence but rather is a general important fitness-related trait, with a higher emission of the sex pheromone measured in the laboratory directly affecting the attractiveness of a male under field conditions. 相似文献
85.
Silke Gabbert Martin van Ittersum Carolien Kroeze Serge Stalpers Frank Ewert Johanna Alkan Olsson 《Regional Environmental Change》2010,10(2):131-143
Integrated Assessment (IA) models aim at providing information- and decision-support to complex problems. This paper argues
that uncertainty analysis in IA models should be user-driven in order to strengthen science–policy interaction. We suggest
an approach to uncertainty analysis that starts with investigating model users’ demands for uncertainty information. These
demands are called “uncertainty information needs”. Identifying model users’ uncertainty information needs allows focusing the analysis on those uncertainties which users
consider relevant and meaningful. As an illustrative example, we discuss the case of examining users’ uncertainty information
needs in the SEAMLESS Integrated Framework (SEAMLESS-IF), an IA model chain for assessing and comparing alternative agricultural
and environmental policy options. The most important user group of SEAMLESS-IF are policy experts at the European and national
level. Uncertainty information needs of this user group were examined in an interactive process during the development of
SEAMLESS-IF and by using a questionnaire. Results indicate that users’ information requirements differed from the uncertainty
categories considered most relevant by model developers. In particular, policy experts called for addressing a broader set
of uncertainty sources (e.g. model structure and technical model setup). The findings highlight that investigating users’
uncertainty information needs is an essential step towards creating confidence in an IA model and its outcomes. This alone,
however, may not be sufficient for effectively implementing a user-oriented uncertainty analysis in such models. As the case
study illustrates, it requires to include uncertainty analysis into user participation from the outset of the IA modelling
process. 相似文献
86.
87.
Jill K. Tjon Melinda M. E. H. Witbreuk Peter A. A. Struijs Bloeme J. van der Knoop Ingeborg H. Linskens Johanna I. P. de Vries 《黑龙江环境通报》2023,43(8):1056-1065
Objective
Children and adults with talipes equinovarus (TEV) have smaller calves and shorter feet compared to non-affected controls. Do these changes have a prenatal onset?Methods
A prospective cohort study (January 2020–July 2021) was conducted with serial ultrasonographic measurements at 20 and 28 weeks gestation and measurements directly and 6 weeks after birth. Calf circumference and width, foot length and length of humerus, ulna, radius, femur, tibia and fibula were measured in TEV and were compared to a control population. Calculated sample size necessitated a minimal population of 10 cases with TEV and 50 controls.Results
Twenty cases with TEV and 62 controls were included. Fetal calf circumference (p < 0.001) and width (p < 0.001) were smaller in the TEV group in comparison to the control group, which persisted after birth. Growth in foot length (p < 0.001) and calf width (p 0.003) declined prenatally over time. The bone lengths and upper leg circumference were not smaller or shorter in TEV compared to controls.Conclusion
This prospective cohort study demonstrated the prenatal onset of reduced calf and foot size in fetuses with TEV from 20 weeks and onwards, which persists directly after birth. To investigate whether reduction in circumference initiates TEV or is caused by TEV, further examination is needed. 相似文献88.
89.
The Nottingham Cycle Friendly Employers Project studied the effectiveness of measures to promote cycling to work by eight large city employers under the 1995 governmentfunded Cycle Challenge. Progress was monitored by ‘before’ and ‘after’ surveys, by examination of the measures, and by discussions with the employers. Overall cycling awareness and activity were increased by the project: 42% of employees said their cycle commuting had increased. The main influences, about equally, were providing workplace cycling facilities, a house or job move making cycling more attractive, and heightened awareness of the importance of regular exercise for health. The most welcomed and best used measures were secure cycle parking, showering and changing facilities, and cycle purchase loans. 相似文献
90.
Alan E. Donnenfeld MD Johanna van de Woestune Frank Craparo Catherine S. Smith Avi Ludomirsky Stuart Weiner 《黑龙江环境通报》1991,11(4):235-244
Experience with three prenatally diagnosed pregnancies complicated by an acardiac twin reveals that ultrasonography and echocardiography are helpful in detecting early signs of in-utero congestive heart failure in the normal twin. The use of Doppler blood flow analysis to determine direction of blood flow, post-mortem placental and fetal angiography, and umbilical cord blood gas determination provided proof that retrograde arterial perfusion occurs in the acardiac fetus. In a fourth pregnancy, an experimental approach to occlude the acardiac twin's umbilical cord was attempted, but was unsuccessful. 相似文献