期刊文献+
共找到71篇文章
< 1 2 4 >
每页显示 20 50 100
COUPLED PHYSICAL-ECOLOGICAL MODELLING IN THE CENTRAL PART OF JIAOZHOU BAY Ⅱ. COUPLED WITH AN ECOLOGICAL MODEL 被引量:8
1
作者 崔茂常 朱海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2001年第1期21-28,共8页
Sharples’ 1 D physical model employing tide wind driven turbulence closure and surface heating cooling physics, was coupled with an ecological model with 9 biochemical components: phytoplankton, zooplankton, shellfis... Sharples’ 1 D physical model employing tide wind driven turbulence closure and surface heating cooling physics, was coupled with an ecological model with 9 biochemical components: phytoplankton, zooplankton, shellfish, autotrophic and heterotrophic bacterioplankton, dissolved organic carbon (DOC), suspended detritus and sinking particles to simulate the annual evolution of ecosystem in the central part of Jiaozhou Bay. The coupled modeling results showed that the phytoplankton shading effect could reduce seawater temperature by 2℃, so that photosynthesis efficiency should be less than 8%; that the loss of phytoplankton by zooplankton grazing in winter tended to be compensated by phytoplankton advection and diffusion from the outside of the Bay; that the incident irradiance intensity could be the most important factor for phytoplankton growth rate; and that it was the bacterial secondary production that maintained the maximum zooplankton biomass in winter usually observed in the 1990s, indicating that the microbial food loop was extremely important for ecosystem study of Jiaozhou Bay. 展开更多
关键词 coupled modelling ecological model central part of Jiaozhou Bay
下载PDF
Stability and Uniform Boundedness for a Class of Anaerobic Digestion Ecological Models
2
作者 李明奇 《Journal of Electronic Science and Technology of China》 2004年第2期87-89,共3页
Stability, boundedness and persistence are three important aspects for an ecological model. In this paper, a further analysis of a class of anaerobic digestion ecological models is performed. Based on the Liupunov Met... Stability, boundedness and persistence are three important aspects for an ecological model. In this paper, a further analysis of a class of anaerobic digestion ecological models is performed. Based on the Liupunov Method, the local stability of all equilibria in the system is got. According to the vector fields described by the system, the proof of the boundedness of the solution on the anaerobic digestion processes is completed in three steps. The method proposed in the discussion on the boundedness can be generalized to the similar problems. Results in this paper give information on how to run the ecological system well by adjusting the system parameters. 展开更多
关键词 anaerobic digestion processes ecological models of microbes STABILITY uniform Boundedness
下载PDF
Data Analyses and Parallel Optimization of the Regional Marine Ecological Model
3
作者 Yanqiang Wang Jingjing Zheng +2 位作者 Tianyu Zhang Peng Liang Bo Lin 《国际计算机前沿大会会议论文集》 EI 2023年第2期213-224,共12页
Under the joint influence of high-intensity human activities and cli-mate change,the coastal ecological environment is deteriorating,and the ecologi-cal environment security and the sustainable development of the marin... Under the joint influence of high-intensity human activities and cli-mate change,the coastal ecological environment is deteriorating,and the ecologi-cal environment security and the sustainable development of the marine economy are seriously threatened.Therefore,it is of great significance to establish a high-resolution ecological environment operational forecasting system.To meet the run time requirements of the ecological operational forecasting system,a vari-ety of parallel optimization methods were proposed to improve the operation efficiency of the model.First,based on the National Marine Environmental Fore-casting Center’s Lenovo cluster,the ROMS benchmark experiment was expanded to the 4000 Processes scale.A good speedup was obtained by the experiment.The ROMS model was analysed with strong scalability.Second,in the hydrodynamic-ecological simulation experiment of the Bohai Sea-Yellow Sea-East China Sea,by optimizing Vector,InfiniBand,and Parallel I/O,the performance of the model can be improved by 270%while maintaining the same computing resources.That computing resources were more reasonably used lay the foundation for the operational forecast. 展开更多
关键词 marine ecological model ROMS high-performance computing parallel optimization
原文传递
An ecological model with the p-Laplacian and diffusion
4
作者 S. H. Rasouli 《International Journal of Biomathematics》 2016年第1期157-163,共7页
We study the existence of positive solutions of a population model with diffusion of the form {-△pu=aup-1-f(u)-c/ua,x∈Ω,u=0,x∈Ω where △p denotes the p-Laplacian operator defined by △pz =div(|z|P-2z), p 〉... We study the existence of positive solutions of a population model with diffusion of the form {-△pu=aup-1-f(u)-c/ua,x∈Ω,u=0,x∈Ω where △p denotes the p-Laplacian operator defined by △pz =div(|z|P-2z), p 〉 1, Ω is a bounded domain of RN with smooth boundary, α∈ C (0, 1), a and e are positive constants. Here f : [0, ∞) → R is a continuous function. This model arises in the studies of population biology of one species with u representing the concentration of the species. We discuss the existence of positive solution when f satisfies certain additional conditions. We use the method of sub- and super-solutions to establish our results. 展开更多
关键词 ecological model infinite semipositone sub- and super-solutions.
原文传递
A Modified Model of Ecological Footprint Accounting and Its Application to Cropland in Jiangsu,China 被引量:21
5
作者 LIU Qin-Pu LIN Zhen-Shan +1 位作者 FENG Nian-Hua LIU Yong-Mei 《Pedosphere》 SCIE CAS CSCD 2008年第2期154-162,共9页
Based on the theory of emergy analysis,a modified model of ecological footprint accounting,termed emergetic ecological footprint(EMEF)in contrast to the conventional ecological footprint(EF)model,is formulated and app... Based on the theory of emergy analysis,a modified model of ecological footprint accounting,termed emergetic ecological footprint(EMEF)in contrast to the conventional ecological footprint(EF)model,is formulated and applied to a case study of Jiangsu cropland,China.Comparisons between the EF and the EMEF with respect to grain,cotton,and food oil were outlined.Per capita EF and EMEF of cropland were also presented to depict the resources consumption level by comparing the biocapacity(BC)or emergetic biocapacity(EMBC,a new BC calculation by emergy analysis) of the same area.In the meanwhile,the ecological sustainability index(ESI),a new concept initiated by the authors, was established in the modified model to indicate and compare the sustainability of cropland use at different levels and between different regions.The results from conventional EF showed that per capita EF of the cropland has exceeded its per capita BC in Jiangsu since 1986.In contrast,based on the EMBC,the per capita EMEF exceeded the per capita EMBC 5 years earlier.The ESIs of Jiangsu cropland use were between 0.7 and 0.4 by the conventional method,while the numbers were between 0.7 and 0.3 by the modified one.The fact that the results of the two methods were similar showed that the modified model was reasonable and feasible,although some principles of the EF and EMEF were quite different. Also,according to the realities of Jiangsu cropland use,the results from the modified model were more acceptable. 展开更多
关键词 CROPLAND ecological footprint model ecological sustainability index EMERGY
下载PDF
Predicting the potential geographic distribution of Bactrocera bryoniae and Bactrocera neohumeralis(Diptera: Tephritidae) in China using MaxEnt ecological niche modeling 被引量:7
6
作者 Jing Wan QI Guo-jun +3 位作者 MA Jun Yonglin REN WANG Rui Simon MCKIRDY 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第8期2072-2082,共11页
Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive and major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific and Australia.Although ... Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive and major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific and Australia.Although these pests have not established in China,precautions must be taken due to their highly destructive nature.Thus,we predicted the potential geographic distribution of B.bryoniae and B.neohumeralis across the world and in particular China by ecological niche modeling of the Maximum Entropy(Max Ent)model with the occurrence records of these two species.Bactrocera bryoniae and B.neohumeralis exhibit similar potential geographic distribution ranges across the world and in China,and each species was predicted to be able to distribute to over 20%of the globe.Globally,the potential geographic distribution ranges for these two fruit fly species included southern Asia,the central and the southeast coast of Africa,southern North America,northern and central South America,and Australia.While within China,most of the southern Yangtze River area was found suitable for these species.Notably,southern China was considered to have the highest risk of B.bryoniae and B.neohumeralis invasions.Our study identifies the regions at high risk for potential establishment of B.bryoniae and B.neohumeralis in the world and in particular China,and informs the development of inspection and biosecurity/quarantine measures to prevent and control their invasions. 展开更多
关键词 fruit fly Bactrocera bryoniae Bactrocera neohumeralis ecological niche modeling MAXENT potential geographic distribution habitat suitability
下载PDF
Human Settlement Evaluation in Mountain Areas Based on Remote Sensing,GIS and Ecological Niche Modeling 被引量:7
7
作者 ZHAO Jian XU Min +1 位作者 LU Shi-lei CAO Chun-xiang 《Journal of Mountain Science》 SCIE CSCD 2013年第3期378-387,共10页
The Qinghai-Tibet Plateau is the word's highest and largest plateau. Due to increasing demands for environment exploration and tourism, a large transitional area is required for altitude adaptation. Hehuang valley, w... The Qinghai-Tibet Plateau is the word's highest and largest plateau. Due to increasing demands for environment exploration and tourism, a large transitional area is required for altitude adaptation. Hehuang valley, which locates in the transition zone between the Loess Plateau and the Qinghai-Tibet Plateau, has convenient transportation and relatively low elevation. Our question is whether the geographic conditions here are appropriate for adapted stay before going into the Qinghai-Tibet Plateau. Therefore, in this study, we examined the potential use of ecological niche modeling (ENM) for mapping current and potential distribution patterns of human settlements. We chose the Maximum Entropy Method (Maxent), an ENM which integrates climate, remote sensing and geographical data, to model distributions and assess land suitability for transition areas. After preprocessing and selection, the correlation between variables and spatial auto- correlation input data were removed and 106 occurrence points and 9 environmental layers were determined as the model inputs. The threshold- independent model performance was reasonable according to lO times model running, with the area under the curve (AUC) values being 0.917± 0.01, and 0.923±0.002 for test data. Cohen's kappa coefficient of model performance was 0.848. Results showed that 82.22% of the study extent was not suitable for human settlement. Of the remaining areas, highly suitable areas aceounted for 1.19%, moderately for 5.3% and marginally for 11.28%. These suitable areas totaled 418.79 km2, and 86.25% of the sample data was identified in the different gradient of suitable area.The decisive environmental factors were slope and two climate variables: mean diurnal temperature range and temperature seasonality. Our model showed a good performance in mapping and assessing human settlements. This study provides the first predicted potential habitat distribution map for human settlement in Ledu County, which could also help in land use management. 展开更多
关键词 Human settlement Remote sensing Suitability assessment ecological niche modeling
下载PDF
EXISTENCE OF NONNEGATIVE SOLUTIONS FOR DEGENERATE ECOLOGICAL MODELS
8
作者 ZHANG SHENGHAI 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第1期8-14,共7页
In this paper,nonnegative solutions for the degenerate elliptic systems are considered.First,nonnegative solutions for scalar equation with spatial discontinuities are studied.Then the method developed for scalar equa... In this paper,nonnegative solutions for the degenerate elliptic systems are considered.First,nonnegative solutions for scalar equation with spatial discontinuities are studied.Then the method developed for scalar equation is applied to study elliptic systems.At last,the existence criteria of nonnegative solutions of elliptic systems are given. 展开更多
关键词 Nonnegative solution elliptic systems ecological models.
全文增补中
Evolution of biogeographic disjunction between eastern Asia and North America in Chamaecyparis:Insights from ecological niche models 被引量:2
9
作者 Ping Liu Jun wen Tingshuang Yi 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第3期111-116,共6页
The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long deb... The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long debated. Chamaecyparis is a good model to test previous hypotheses about the formation of this disjunct pattern as it contains six species disjunctly distributed in EA, western North America(WNA)and eastern North America(ENA). In this study, we applied ecological niche models to test the formation of the disjunct pattern of Chamaecyparis. The model calibrated with the EA species was able to predict the distribution of eastern NA species well, but not the western NA species. Furthermore, the eastern Asian species were shown to have higher niche overlap with the eastern North American species. The EA species were also shown to share more similar habitats with ENA species than with WNA species in the genus. Chamaecyparis species in WNA experienced a significant niche shift compared with congeneric species. Chamaecyparis had a low number of suitable regions in Europe and the middle and western NA during the Last Glacial Maximum(LGM) period, and became extinct in the former region whereas it retains residual distribution in the latter. The extirpations in western NA and Europe in response to the late Neogene and Quaternary climatic cooling and the more similar habitats between ENA and EA ultimately shaped the current intercontinental disjunct distribution of Chamaecyparis. Both current hypotheses may be also jointly applied to explain more eastern Asian and eastern North American disjunctions observed today. 展开更多
关键词 DISJUNCTION Eastern Asia North America CHAMAECYPARIS ecological niche models MAXENT
下载PDF
A Study on the Ecological Teaching Model of College English from the Perspective of Ecological Linguistics
10
作者 刘爱芹 《海外英语》 2021年第10期277-278,共2页
Teachers' teaching concepts, language skills and so on are directly related to teaching methods, and have a profound impact on English teaching. Eco-linguistics is mainly an interdisciplinary subject of language d... Teachers' teaching concepts, language skills and so on are directly related to teaching methods, and have a profound impact on English teaching. Eco-linguistics is mainly an interdisciplinary subject of language development and change from the perspective of ecology. It is helpful to create a favorable teaching environment, arouse students' interest in learning and improve the quality of classroom teaching. With the help of application tools such as"Rain classroom", this paper mainly focuses on the ecological teaching mode of college English from the perspective of ecological linguistics in detail such as individualized assignment and group work etc, hoping to be helpful to the relevant personnel. 展开更多
关键词 eco-Linguistics college English ecological teaching model "Rain classroom"
下载PDF
Modelling the probability of presence of Aedes aegypti and Aedes albopictus in Iran until 2070
11
作者 Mohammad Mehdi Sedaghat Faramarz Bozorg Omid +2 位作者 Mohammad Karimi Sajjad Haghi Ahmad Ali Hanafi-Bojd 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第1期16-25,共10页
Objective:To determine the suitable ecological habitats of Aedes(Ae.)aegypti and Ae.albopictus in Iran due to climate change by the 2070s.Methods:All data relating to the spatial distribution of Ae.aegypti and Ae.albo... Objective:To determine the suitable ecological habitats of Aedes(Ae.)aegypti and Ae.albopictus in Iran due to climate change by the 2070s.Methods:All data relating to the spatial distribution of Ae.aegypti and Ae.albopictus worldwide,which indicated the geographical coordinates of the collection sites of these mosquitoes,were extracted from online scientific websites and entered into an Excel file.The effect of climatic and environmental variables on these mosquitoes was evaluated using the MaxEnt model in the current and future climatic conditions in the 2030s,2050s,and 2070s.Results:The most suitable areas for the establishment of Ae.aegypti are located in the southern and northern coastal areas of Iran,based on the model outputs.The modelling result for suitable ecological niches of Ae.albopictus shows that in the current climatic conditions,the southern half of Iran from east to west,and parts of the northern coasts are prone to the presence of this species.In the future,some regions,such as Gilan and Golestan provinces,will have more potential to exist/establish Ae.albopictus.Also,according to the different climate change scenarios,suitable habitats for this species will gradually change to the northwest and west of the country.The temperature of the wettest season of the year(Bio8)and average annual temperature(Bio1)were the most effective factors in predicting the model for Ae.aegypti and Ae.albopictus,respectively.Conclusions:It is required to focus on entomological studies using different collection methods in the vulnerable areas of Iran.The future modelling results can also be used for long-term planning to prevent the entry and establishment of these invasive Aedes vectors in the country. 展开更多
关键词 Aedes aegypti Aedes albopictus Dengue fever CHIKUNGUNYA ecological Niche modeling Climate change
下载PDF
Research on the hydrogeochemical model for water resources and ecological environment
12
《Global Geology》 1998年第1期84-84,共1页
关键词 Research on the hydrogeochemical model for water resources and ecological environment
下载PDF
Study on Influencing Factors of Mental Health of Mobile Young White-Collar Workers in China
13
作者 Tao Liu Lin Liu +1 位作者 Zeyu Chen Rong Fu 《International Journal of Mental Health Promotion》 2024年第2期127-138,共12页
Mobile young white-collar workers not only have the characteristics of mobile young people,but also have the characteristics of general white-collar workers.Under the influence of both,their mental health may be suffe... Mobile young white-collar workers not only have the characteristics of mobile young people,but also have the characteristics of general white-collar workers.Under the influence of both,their mental health may be suffering from“double disadvantage”.So,based on an ecological model of the stress process,this paper tries to use the data of the questionnaire on the mental health of mobile young white-collar workers in Zhejiang Province to explore the influence of some factors in the middle workplace and residence place on the mental health of micro individuals.The results show that:(1)The working environment with high control and low freedom and the workplace discrimination against the mobile status will have a negative impact on the mental health of mobile young white-collar workers;(2)Financial anxiety in daily life will lead to a decline in the mental health level of mobile young white-collar workers;(3)Good organizational support and neighborhood social relations can significantly relieve life pressure,so as to effectively improve the mental health of mobile young white-collar workers.It can be seen that we also need to pay more attention to the mental health of mobile young white-collar workers in order to improve their situation. 展开更多
关键词 Mobile population young white-collar workers mental health ecological model stress process
下载PDF
Model study on Bohai ecosystem 1. Model description and primary productivity 被引量:4
14
作者 LIU Hao YIN Baoshu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第4期77-90,共14页
A Nutrient -Phytoplankton -Zooplankton(NPZD) type of ecological model is developed to reflect the biochemical process, and further coupled to a primitive equation ocean model, an irradiation model as well as a river... A Nutrient -Phytoplankton -Zooplankton(NPZD) type of ecological model is developed to reflect the biochemical process, and further coupled to a primitive equation ocean model, an irradiation model as well as a river discharge model to reproduce ecosystem dynamics in the Bohai Sea. Modeled primary production shows reasonable consistency with observations quantitatively and qualitatively; in addition, f-ratio is examined in detail in the first time, which is also within the range reported in other studies and reveals some meaningful insight into the relative contributions of ammonium and nitrate to the growth of phytoplankton in the Bohai Sea. 展开更多
关键词 Bohai Sea NPZD type of ecological model primary production F-RATIO
下载PDF
Model assessment of nutrient removal via planting Sesuvium portulacastrum in floating beds in eutrophic marine waters:the case of aquaculture areas of Dongshan Bay 被引量:3
15
作者 Xuehai Liu Xinming Pu +2 位作者 Donglian Luo Jing Lu Zili Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第12期91-100,共10页
Many coastal seas are severely eutrophic and required to reduce nutrient concentrations to meet a certain water quality standard.We proposed a method for nutrient removal by planting Sesuvium portulacastrum at the wat... Many coastal seas are severely eutrophic and required to reduce nutrient concentrations to meet a certain water quality standard.We proposed a method for nutrient removal by planting Sesuvium portulacastrum at the water surface using the floating beds in the aquaculture area of the Dongshan Bay as an example,which is an important net-cage culture base in China and where dissolved inorganic nitrogen(DIN)and dissolved inorganic phosphate(DIP)reach 0.75 mg/L and 0.097 mg/L,respectively far exceeding China’s Grade IV water quality standards.Numerical simulations were taken using the ecological model,field observations and field plantation experimental results to assess the environmental restoration effects of planting S.portulacastrum at some certain spatial scales.Our field experiments suggested that the herbs can absorb 377 g/m^2 nitrogen and 22.9 g/m^2 phosphorus in eight months with an inserting density of^60 shoot/m^2.The numerical experiments show that the greater the plantation area is,the more nutrient removal.Plantation in^12%of the study area could lower nutrients to the required Grade II standards,i.e.,0.2 mg/L<DIN≤0.3 mg/L and 0.015 mg/L<DIP≤0.03 mg/L.Here the phytoremediation method and results provide helpful references for environmental restoration in other eutrophic seas. 展开更多
关键词 phytoremediaton Sesuvium portulacastrum ecological model nutrient removal
下载PDF
Health-related quality of life in Parkinson's disease patients in northeastern Sicily, Italy An ecological perspective 被引量:1
16
作者 Letteria Spadaro Lilla Bonanno +2 位作者 Giuseppe Di Lorenzo Placido Bramanti Silvia Marino 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第17期1615-1622,共8页
Parkinson's disease has a negative impact on health-related quality of life in Parkinson's disease patients. Depression, cognitive impairment, coping strategies, dyskinesia, gait disorders and complications of dopam... Parkinson's disease has a negative impact on health-related quality of life in Parkinson's disease patients. Depression, cognitive impairment, coping strategies, dyskinesia, gait disorders and complications of dopaminergic drugs are the variables that most affect health-related quality of life. The ecological model of human development focuses attention on both individual and social environmental factors as targets for health interventions. From this perspective, the aim of this cross-sectional survey was to evaluate the influence of gender, family size and perceived autonomy on health-related quality of life in Parkinson's disease patients in nOrtheastern Sicily, Italy. Ninety Parkinson's disease patients, attending the Movement Disorders Clinic at IRCCS Centro Neurolesi "Bonino-Pulejo" (Messina), were consecutively enrolled. The Unified Parkinson Disease Rating Scale motor subscale (UPDRS-Ⅲ) scores, the Parkinson Disease Questionnaire-39 Item scores (as a disease-specific measure of health-related quality of life), scores on the Short Form (36) Health Survey Questionnaire (as a generic measure), and answers to a brief checklist were recorded. A total of 85 Parkinson's disease patients (49% males and 51% females; mean age 70.8 ± 8.6 years mean UPDRS-Ⅲ 24.15 ± 6.55; mean disease duration 5.52 ± 4.65 years) completed the booklet of questionnaires. In the multivariate regression analysis, we included clinical and social variables as independent predictors of health-related quality of life. Our results suggest a potential compounding effect of ecological intrapersonal and interpersonal levels on health-related quality of life outcomes. Gender, self-evaluated autonomy and family size significantly impacted health-related quality of life. If quality of life is used as an indicator of treatment outcomes, an ecological perspective of the case history will be important to disclose relevant prognostic information and trigger personalized health care interventions. 展开更多
关键词 neural regeneration neurodegenerative disease health-related quality of life Parkinson's disease ecological model Parkinson's Disease Questionnaire-39 Items social variables the UnifiedParkinson Disease Rating Scale motor subscales CAREGIVER grants-supported paper
下载PDF
Elevation transition of aquatic insects closely matches a thermal feature in the Yungas of Northwestern Argentina
17
作者 Alexandra BUITRAGO-GUACANAME Carlos MOLINERI +1 位作者 Andrés LIRA-NORIEGA Daniel Andrés DOS SANTOS 《Journal of Mountain Science》 SCIE CSCD 2024年第2期433-448,共16页
Temperature is a key factor that shapes the distribution of organisms.Having knowledge about how species respond to temperature is relevant to devise strategies for addressing the impacts of climate change.Aquatic ins... Temperature is a key factor that shapes the distribution of organisms.Having knowledge about how species respond to temperature is relevant to devise strategies for addressing the impacts of climate change.Aquatic insects are particularly vulnerable to climate change,yet there is still much to learn about their ecology and distribution.In the Yungas ecoregion of Northwestern Argentina,cold-and warm-adapted species of the orders Ephemeroptera,Plecoptera,and Trichoptera(EPT)are segregated by elevation.We modeled the ecological niche of South American EPT species in this region using available data and projected their potential distribution in geographic space.Species were grouped based on their ecogeographic similarity,and we analyzed their replacement pattern along elevation gradients,focusing on the ecotone where opposing thermal preferences converge.Along this interface,we identified critical points where the combined incidence of cold and warm assemblages maximizes,indicating a significant transition zone.We found that the Montane Cloud Forest holds the interface,with a particularly greater suitability at its lower boundary.The main axis of the interface runs in a N-S direction and falls between 14°C-16°C mean annual isotherms.The probability of a particular location within a basin being classified as part of the interface increases as Kira’s warmth index approaches a score around 150.Understanding the interface is critical for defining the thermal limits of species distribution and designing biomonitoring programs.Changes in the location of thermal constants related to mountainous ecotones may cause vertical displacement of aquatic insects and vegetation communities.We have recognized significant temperature thresholds that serve as indicators of suitability for the interface.As global warming is anticipated to shift these indicators,we suggest using them to monitor the imprints of climate change on mountain ecosystems. 展开更多
关键词 Austral Yungas ecological Niche model EPHEMEROPTERA Kira’s warmth index PLECOPTERA TRICHOPTERA
下载PDF
Path-dependent speciation in dynamic fitness landscapes
18
作者 Min-Lan Li Chao Wang Rui-Wu Wang 《Zoological Research(Diversity and Conservation)》 2024年第2期133-140,共8页
Species is a fundamental concept in evolutionary biology and biodiversity.However,existing species definitions are often influenced by artificial factors or are challenging in practical application,leading to confusio... Species is a fundamental concept in evolutionary biology and biodiversity.However,existing species definitions are often influenced by artificial factors or are challenging in practical application,leading to confusion in species classification.Due to uncertain environmental changes and random genetic drift,the fitness expectations of a population may shift,causing species to evolve to a new evolutionary state based on their current instantaneous fitness within a dynamic fitness landscape.This contrasts with the classic static fitness landscape,where fitness expectations are constant.In a dynamic fitness landscape,speciation may exhibit path dependence,where the evolution of traits follows a probabilistic path,creating feedback that shapes evolutionary trajectories.The path-dependent evolutionary mechanism suggests that species survival within an ecosystem is not directly determined by their fitness but by the probability of their evolutionary pathways.This model also indicates that species can coexist with varying probabilities under limited environmental pressures.Consequently,new species,cryptic species,or sympatric species may emerge via path-dependent evolutionary processes.Within this framework,we developed a mathematical species concept,which may guide future species classification methodologies. 展开更多
关键词 BIODIVERSITY ecological/evolutionary model Fitness landscape Stochastic process Path dependence
下载PDF
Linking Structural Equation Modeling with Bayesian Network and Its Application to Coastal Phytoplankton Dynamics in the Bohai Bay
19
作者 XU Xiao-fu SUN Jian +2 位作者 NIE Hong-tao YUAN De-kui TAO Jian-hua 《China Ocean Engineering》 SCIE EI CSCD 2016年第5期733-748,共16页
Bayesian networks (BN) have many advantages over other methods in ecological modeling, and have become an increasingly popular modeling tool. However, BN are flawed in regard to building models based on inadequate e... Bayesian networks (BN) have many advantages over other methods in ecological modeling, and have become an increasingly popular modeling tool. However, BN are flawed in regard to building models based on inadequate existing knowledge. To overcome this limitation, we propose a new method that links BN with structural equation modeling (SEM). In this method, SEM is used to improve the model structure for BN. This method was used to simulate coastal phytoplankton dynamics in the Bohai Bay. We demonstrate that this hybrid approach minimizes the need for expert elicitation, generates more reasonable structures for BN models, and increases the BN model's accuracy and reliability. These results suggest that the inclusion of SEM for testing and verifying the theoretical structure during the initial construction stage improves the effectiveness of BN models, especially for complex eco-environment systems. The results also demonstrate that in the Bohai Bay, while phytoplankton biomass has the greatest influence on phytoplankton dynamics, the impact of nutrients on phytoplankton dynamics is larger than the influence of the physical environment in summer. Furthermore, although the Redfield ratio indicates that phosphorus should be the primary nutrient limiting factor, our results show that silicate plays the most important role in regulating phytoplankton dynamics in the Bohai Bay. 展开更多
关键词 structural equation modeling Bayesian networks ecological modeling Bohai Bay phytoplankton dynamics
下载PDF
Towards an Ecological Understanding of Translation Etemality in the Context of Iran
20
作者 Maryam Shirdel Majid Elahi Shirvan 《Sino-US English Teaching》 2016年第6期468-491,共24页
This study attempted to investigate the similarities and differences regarding the conceptions of translation eternality among a small group of Iranian people of different social positions and different ages. Sixty-tw... This study attempted to investigate the similarities and differences regarding the conceptions of translation eternality among a small group of Iranian people of different social positions and different ages. Sixty-two participants were selected based on the maximum variation sampling. To gather data, semi-structured interview was utilized. The participants were asked a list of 11 questions collected from the existing literature on the similar topics. Then, the interviews were transcribed for analyzing the data. Besides, Erikson's (1959) theory of development was used to classify participants of different ages in four groups of teenager, young, middle age, and old. The high frequency factors were found and analyzed with the use of Bronfenbrenner's (1979) nested ecological model. Moreover, the participants were classified in 11 groups based on their social positions and their conceptions were analyzed with the same method. Broadly speaking, 17 central tendencies in the interviews were obtained: People mainly focused on subjects of the books, translation fluency, author's competence in writing, and translator's competence, translations which have common grounds with social events of Iran, advertisement, existence of movie or cartoon adaptation of the book, translator's awareness of the content of the book, existence of cultural similarities between the source and target culture, popularity of the translator, author, and the original book, conversational language in translation, translation fidelity, being both translator and author, and effect of censorship on translation. Besides, old participants seemed to have more precise view on translation eternality and teenager's concerns were mostly about the appearance-related issues. 展开更多
关键词 translation etemality ecological understanding nested ecological model translation competence translation fidelity
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部