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Seasonal waterbird population changes in Lashihai Lake in northwest Yunnan, China 被引量:3
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作者 LIAO Jun-tao YE Hui +1 位作者 HUANG Ting-fa PENG Gui-hong 《Journal of Mountain Science》 SCIE CSCD 2017年第9期1852-1862,共11页
We studied the waterbird population at Lashihai Lake, Yunnan Province, China, which is a Ramsar Site(Wetland of International Importance), to determine seasonal variation in the species composition and size of the wat... We studied the waterbird population at Lashihai Lake, Yunnan Province, China, which is a Ramsar Site(Wetland of International Importance), to determine seasonal variation in the species composition and size of the waterbird population. The study was conducted at five selected spots along Lashihai Lake at the same time each week from August 2011 to September 2013. In total, 62 waterbird species were recorded, of which 38.71%, 35.48%, 16.13%, and 9.68% were winter migrants, passage visitors, residents, and summer migrants, respectively. We found important seasonal changes in waterbird species composition and population size. Waterbird species richness was highest from September to the following April, with the total species numbers peaking in December. Total individual numbers peaked twice from late November to early December and mid-to-late February. However, waterbird species and individual numbers were comparatively lower from May to August. The change in species composition was determined by the arrival and departure dynamics of winter migrants and passage visitors. Winter migrants primarily caused the periodic changes in population size. Of concern,species and overall waterbird numbers seemed to be lower than the numbers in historical records. The decline of waterbird numbers implies that environmental changes caused by the implementation of the dam upstream of Lashihai Lake may have had adverse effects on this waterbird population. This study confirms the existence of major seasonal changes in species composition and size of the waterbird population at Lashihai Lake. Furthermore, the findings demonstrate that this wetland is of high conservation importance for waterbirds using the Central Asian–Indian and Asian–Pacific migratory routes. 展开更多
关键词 Seasonal variation Species number Individual number Waterbird population
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Development of the IAP Dynamic Global Vegetation Model 被引量:16
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作者 ZENG Xiaodong LI Fang SONG Xiang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第3期505-514,共10页
ABSTRACT The lAP Dynamic Global Vegetation Model (IAP-DGVM) has been developed to simulate the distribution and structure of global vegetation within the framework of Earth System Models. It incorporates our group... ABSTRACT The lAP Dynamic Global Vegetation Model (IAP-DGVM) has been developed to simulate the distribution and structure of global vegetation within the framework of Earth System Models. It incorporates our group's recent developments of major model components such as the shrub sub-model, establishment and competition parameterization schemes, and a process-based fire parameterization of intermediate complexity. The model has 12 plant functional types, including seven tree, two shrub, and three grass types, plus bare soil. Different PFTs are allowed to coexist within a grid cell, and their state variables are updated by various governing equations describing vegetation processes from fine-scale biogeophysics and biogeochemistry, to individual and population dynamics, to large-scale biogeography. Environmental disturbance due to fire not only affects regional vegetation competition, but also influences atmospheric chemistry and aerosol emissions. Simulations under observed atmospheric conditions showed that the model can correctly reproduce the global distribution of trees, shrubs, grasses, and bare soil. The simulated global dominant vegetation types reproduce the transition from forest to grassland (savanna) in the tropical region, and from forest to shrubland in the boreal region, but overestimate the region of temperate forest. 展开更多
关键词 Dynamic Global Vegetation Model individual and population dynamics BIOGEOGRAPHY DISTURBANCE
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Blood pressure differences in people with various individual characteristics in Guangdong Province
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作者 麦劲壮 饶栩栩 刘小清 《South China Journal of Cardiology》 CAS 2001年第2期76-79,共4页
Objective To study the differences in blood pressure (BP) levels and the main factors raising BP among the population in Guangdong Province. Methods The data analyzed stem from the sampling survey of hypertension in G... Objective To study the differences in blood pressure (BP) levels and the main factors raising BP among the population in Guangdong Province. Methods The data analyzed stem from the sampling survey of hypertension in Guangdong Province in 1991, covering 42, 894 subjects over 15 years old. Individual characteristics included age, sex, occupation, education, smoking, alcohol drinking and body mass index (BMI) . Results Systolic and diastolic BP increased with age. The hypertension prevalence rate in male is higher than in female. The age - adjusted prevalence rate in office personnel is the highest (12.9 % ) among all occupations. It was increased with education level and BMI (in people educated at university and over is 13. 1 % ), and higher in smokers and alcohol-drinkers than non-smokers and non -alcohol-drinkers. Conclusions Age, occupation, education, smoking, alcohol drinking and BMI all effect BP. These risk factors should be reduced in the Guangdong population. 展开更多
关键词 population Individual characteristics Blood pressure Risk factors
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A primer on multiscale modelling of infectious disease systems
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作者 Winston Garira 《Infectious Disease Modelling》 2018年第1期176-191,共16页
The development of multiscale models of infectious disease systems is a scientific endeavour whose progress depends on advances on three main frontiers:(a)the conceptual framework frontier,(b)the mathematical technolo... The development of multiscale models of infectious disease systems is a scientific endeavour whose progress depends on advances on three main frontiers:(a)the conceptual framework frontier,(b)the mathematical technology or technical frontier,and(c)the scientific applications frontier.The objective of this primer is to introduce foundational concepts in multiscale modelling of infectious disease systems focused on these three main frontiers.On the conceptual framework frontier we propose a three-level hierarchical framework as a foundational idea which enables the discussion of the structure of multiscale models of infectious disease systems in a general way.On the scientific applications frontier we suggest ways in which the different structures of multiscale models can serve as infrastructure to provide new knowledge on the control,elimination and even eradication of infectious disease systems,while on the mathematical technology or technical frontier we present some challenges that modelers face in developing appropriate multiscale models of infectious disease systems.We anticipate that the foundational concepts presented in this primer will be central in articulating an integrated and more refined disease control theory based on multiscale modelling-the all-encompassing quantitative representation of an infectious disease system. 展开更多
关键词 Multiscale models of infectious diseases Immuno-epidemiological models Linking individual/lower/micro and population/upper/macro scales Comparative effectiveness research
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