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81.
R. T. Abdala-Díaz A. Cabello-Pasini E. Pérez-Rodríguez R. M. Conde Álvarez F. L. Figueroa 《Marine Biology》2006,148(3):459-465
Effects of solar radiation on phenolic compound concentrations and photosynthetic activity, estimated as in vivo chlorophyll
fluorescence, in the brown alga Cystoseira tamariscifolia (Hudson) Papenfuss were analyzed in southern Spain from June 1988 to July 2000. Annual and diurnal variations of optimum
quantum yield were negatively correlated with incident irradiance. Optimum quantum yield decreased as irradiance increased
at noon, and yield values recovered in the afternoon suggesting a dynamic photoinhibition. The annual and daily fluctuations
of phenolic compound concentration in the tissue of C. tamariscifolia showed contrasting patterns. There was an annual cycle of phenolic compound concentration in the apical thallus, which was
positively correlated with incident irradiance. The increase in phenolic compounds, however, was twofold greater in the first
half of the year than the decrease during the second half of the year. In contrast to the annual cycle, there appeared to
be a negative correlation between phenolic compound concentration and irradiance in the summer months while no specific relationship
was observed in the fall–winter months. Loss of phenolic compounds from the tissue to the surrounding water was increased
as irradiation dosage increased. This suggests that the decrease of phenolic compounds during the diurnal cycle might be regulated
by the exudation of these compounds at high irradiances in the field. Collectively, our results suggest that, like dynamic
photoinhibition, the rapid synthesis and turnover time of phenolic compounds in the tissue of C. tamariscifolia might serve as photoprotective mechanisms against high irradiances. 相似文献
82.
César García-Hernández José-Luis Huertas-Talón Eduardo J. Sánchez-Álvarez Javier Marín-Zurdo 《International journal of occupational safety and ergonomics》2016,22(1):116-124
This 8-week study evaluates the effects of customized foot orthoses on work-related musculoskeletal disorders (WMSDs) of metal industry workers. These WMSDs were evaluated applying the Nordic musculoskeletal questionnaire (NMQ) at three different times (start, 4th week and 8th week) and additional questions were also formulated to obtain information about adaptation, fatigue, comfort and possible improvements. According to the NMQ results, statistical significance was found in the improvements after 4?weeks (p?<?0.05 in two areas, p?<?0.01 in three areas, p?<?0.001 in two areas and no significance in the other two) and after 8?weeks (p?<?0.01 in three areas, p?<?0.001 in four areas and no significance in the other two). The additional questions indicated fatigue reduction (both in general and in lower extremity), comfort level increase (after the adaptation period) and good acceptance, according to workers’ answers, suggesting customized orthoses can be effective in reducing and preventing WMSDs in several body regions. 相似文献
83.
Evaluation of Satellite‐Derived Rainfall Data for Multiple Physio‐Climatic Regions in the Santiago River Basin,Mexico 下载免费PDF全文
J.R. Ávila‐Carrasco H.E. Júnez‐Ferreira P.H. Gowda J.L. Steiner D.N. Moriasi P.J. Starks J. Gonzalez A.A. Villalobos C. Bautista‐Capetillo 《Journal of the American Water Resources Association》2018,54(5):1068-1086
Assessment of water resources requires reliable rainfall data, and rain gauge networks may not provide adequate spatial representation due to limited point measurements. The Tropical Rainfall Measuring Mission (TRMM) provides rainfall data at global scale, and has been used with good results. However, TRMM data are an indirect measurement of rainfall, and therefore must be validated for its proper use. In this work, a validation scheme was designed and implemented to compare the TRMM Version 7 (V7) monthly rainfall product at different time frames with data measured in two hydrologic subregions of the Santiago River Basin (SRB) in Mexico: Río Alto Santiago and Río Bajo Santiago (RBS). Additionally, three physio‐climatic regions provide an assessment of the interplay of topography, distance from coastal regions, and seasonal weather patterns on the correspondence between both datasets. The TRMM V7 rainfall product exhibited good agreement with the rain gauge data particularly for the RBS and for the whole SRB during wettest summer and autumn seasons. However, strong regional dependence was observed due to differences in climate and topography. Overall, in spite of some noted underestimations, the monthly TRMM V7 rainfall product was found to provide useful information that can be used to complement limited monitoring as is the case of RBS. An improved combined rainfall product could be generated and thus gaining the most benefits from both data sources. 相似文献
84.
Isabel Gallego-Álvarez Luis Rodríguez-Domínguez Isabel-María García-Sánchez 《Journal of Cleaner Production》2011,19(9-10):912-926
The purpose of this research is to analyze different factors behind the disclosure of corporate information on issues related to opportunities arising from climate change worldwide.To achieve that purpose we formulated a dependency model in which the dependent variable corresponds to the creation of a disclosure index on greenhouse gas emissions based on the opportunities arising from climate change and disclosed by companies on their websites. The sample used comprises companies from different countries and activity sectors considered as the most sensitive to greenhouse gas emissions.The results obtained point out that companies with higher environmental performance disclose a larger volume of information on opportunities arising from climate change on their websites, compared to companies with lower environmental performance. Likewise, companies from countries that have ratified the Kyoto Protocol disclose a higher volume of information on greenhouse gas emissions on their websites, compared to companies from countries which have not ratified it. 相似文献
85.
Árpád Nosticzius 《Journal of environmental science and health. Part. B》2013,48(3):465-468
Abstract Trace amounts of 2,4‐D ‐ which does not cause visible damage in plant ‐ are detectable in plant leaves by chlorophyll fluorescence regeneration in two ways. (I) In illuminated leaves the level of first and second fluorescence peak differ in treated and untreated leaves. (2) By taking buffer solution (pH=8.6) in dark‐adapted leaves under vacuum, the first, second and the other fluorescence decrease levels differ in untreated and 2,4‐D or MCPA treated leaves. 相似文献
86.
Corina Başnou Enrique Álvarez Guillem Bagaria Moisès Guardiola Rosó Isern Paloma Vicente Joan Pino 《Environmental management》2013,52(4):971-980
Land use and land cover change (LUCC) is an acknowledged cause of the current biodiversity crisis, but the link between LUCC and biodiversity conservation remains largely unknown at the regional scale, especially due to the traditional lack of consistent biodiversity data. We provide a methodological approach for assessing this link through defining a set of major pressures on biodiversity from LUCC and evaluating their extent, distribution, and association with a set of physical factors. The study was performed in the Metropolitan Region of Barcelona (MRB, NE of Spain) between 1956 and 2000. We generated a LUCC map for the time period, which was reclassified into a set of pressures on biodiversity (forestation, deforestation, crop abandonment, and urbanization). We then explored the association of these pressures with a set of physical factors using redundancy analysis (RDA). Pressures encompassed 38.8 % of the MRB area. Urbanization and forestation were the dominating pressures, followed by crop abandonment and deforestation. RDA showed a significant distribution gradient of these pressures in relation to the studied physical factors: while forestation and deforestation are concentrated in remote mountain areas, urbanization mainly occurs in lowlands and especially on the coast, and close to previous urban centers and roads. Unchanged areas are concentrated in rainy and relatively remote mountain areas. Results also showed a dramatic loss of open habitats and of the traditional land use gradient, both featuring Mediterranean landscapes and extremely important for their biodiversity conservation. Implications of these results for biodiversity management are finally discussed. 相似文献
87.
The Environmental Impact of Shrimp Aquaculture: Causes, Effects, and Mitigating Alternatives 总被引:3,自引:0,他引:3
FEDERICO PÁEZ-OSUNA 《Environmental management》2001,28(1):131-140
Attracted by the demand for shrimp in the developed countries, shrimp aquaculture has expanded rapidly, mainly in the subtropical
and tropical lowlands of America and Asia. This work provides a global review and viewpoint on the environmental impacts of
shrimp aquaculture, considering the causes and effects of the siting and operation of shrimp ponds and abandonment of farm
facilities. Additionally, mitigating alternatives are discussed. To date, approximately 1–1.5 million ha of coastal lowlands
have been converted into shrimp ponds, comprising mainly salt flats, mangrove areas, marshes, and agricultural lands. The
impact of shrimp farming of most concern is the destruction of mangroves and salt marshes for pond construction. Compatibility
with other users, the presence of buffer zones, maintaining an acceptable balance between mangroves and shrimp pond area,
improved pond design, reduction of water exchange, and an improved residence time of water, size and capacity to assimilate
effluents of the water body, are examples of ways to mitigate the adverse effects. The use of mangroves and halophytes as
biofilters of shrimp pond effluents offers an attractive tool for reducing the impact in those regions where mangrove wetlands
and appropriate conditions for halophyte plantations exist. Healthy seed supply, good feed with the use of prophylactic agents
(including probiotics), good water quality, and lower stocking densities are examples of actions suggested to control disease
in shrimp farming. Finally, in the context of integrated management, research priorities are suggested. 相似文献
88.
89.
MARCELA ARAIZA LUIS CARRILLO RURIK LIST CARLOS A. LÓPEZ GONZÁLEZ ENRIQUE MARTÍNEZ MEYER PATRICIA G. MARTÍNEZ‐GUTIÉRREZ OSCAR MOCTEZUMA NAHUM E. SÁNCHEZ‐MORALES JORGE SERVÍN 《Conservation biology》2012,26(4):630-637
Abstract: Given the conflict with human interests that in many cases results in the extirpation of large carnivores, acceptance of their reintroduction is a considerable challenge. By the 1980s Mexican wolves (Canis lupus) were extinct in the wild. In 1998 a population was reintroduced in the Blue Range Mountains of New Mexico (U.S.A.). Efforts to reintroduce the species in Mexico have been ongoing since the late 1980s. Four teams working independently identified 6 areas in northern Mexico in the historic range of Mexican wolves, where reintroductions could potentially be successful. Each team used different methods and criteria to identify the areas, which makes it difficult to prioritize among these areas. Therefore, members of the different teams worked together to devise criteria for use in identifying priority areas. They identified areas with high, intermediate, and low potential levels of conflict between wolves and humans. Areas with low potential conflict had larger buffers (i.e., distance from human settlement to areas suitable for wolves) around human settlements than high‐ and intermediate‐conflict areas and thus were thought most appropriate for the first reintroduction. High‐conflict areas contained habitat associated with wolf presence, but were closer to human activity. The first reintroduction of Mexican wolves to Mexico occurred in October 2011 in one of the identified low‐conflict areas. The identification of suitable areas for reintroduction represents a crucial step in the process toward the restoration of large carnivores. Choice of the first reintroduction area can determine whether the reintroduction is successful or fails. A failure may preclude future reintroduction efforts in a region or country. 相似文献
90.