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Spatio-temporal differentiation of landscape ecological niche in western ecological frangible region: A case study of Yan'an region in northwestern China 被引量:8
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作者 REN Zhiyuan WANG Lixia 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期479-486,共8页
In this study, we attempt to put forward a conception of landscape ecological niche, enlightened by international scholars on extending the ecological niche theory from spatial niche to functional niche. That is helpf... In this study, we attempt to put forward a conception of landscape ecological niche, enlightened by international scholars on extending the ecological niche theory from spatial niche to functional niche. That is helpful for comprehensively appraising landscape spatial patterns and ecological functions, also, presents a new method for analyzing landscape features from multidimensional aspects. The practice process is demonstrated by taking Yan'an region in northwestern China as a case. Firstly, the indices system including spatial attribute and functional attribute is established for assessing landscape ecological niche. Additionally, two-dimensional figures are drawn for comparing the spatio-temporal features of landscape ecological niche in 1987 and 2000 among the 13 administrative counties. The results show that from 1987 to 2000, towards Yan'an region, spatial attribute value of landscape ecological niche changes from 1.000 to 1.178 with an obvious increment, and functional attribute value changes from 0.989 to 1.069 with a little increment, both of which enhance the regional landscape ecological niche. Towards each county, spatial attribute value of landscape ecological niche increases to different extent while functional attribute value changes dissimilarly with an increment or a decrement. 展开更多
关键词 Yah'an region landscape ecological niche spaflo-temporal differentiation
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Human Settlement Evaluation in Mountain Areas Based on Remote Sensing,GIS and Ecological Niche Modeling 被引量:8
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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
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Predicting the potential geographic distribution of Bactrocera bryoniae and Bactrocera neohumeralis(Diptera: Tephritidae) in China using MaxEnt ecological niche modeling 被引量:7
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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
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Evolution of biogeographic disjunction between eastern Asia and North America in Chamaecyparis:Insights from ecological niche models 被引量:2
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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
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Epiphytic orchids and their ecological niche under anthropogenic influence in central Himalayas,Nepal 被引量:4
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作者 ADHIKARI Yagya Prasad FISCHER Anton FISCHER Hagen Siegfried 《Journal of Mountain Science》 SCIE CSCD 2016年第5期774-784,共11页
The survival chance of epiphytie orchids today not only depends on the natural site conditions required by the orchids but also on anthropogenic changes in site conditions. This study answers two questions: (1) Wha... The survival chance of epiphytie orchids today not only depends on the natural site conditions required by the orchids but also on anthropogenic changes in site conditions. This study answers two questions: (1) What is the ecological niche of the different epiphytic orchid species? (2) What are the ecological factors that threaten epiphytic orchid's population under anthropogenic disturbances? Our study area was the Kathmandu valley, Nepal, with its subtropical forest. We established 156 systematically selected sampling points in the Kathmandu area covering different types of ecosystems under human impacts such as densely populated area, agricultural land, mixed agricultural and settled area, old tree patches, and a natural forest in a national park. The ecological niche of the orchid species was analyzed with a principal component analysis (PCA). The correlations between the different site factors were statistically significant. Spearman's rank correlation matrices showed that the variables land-use intensities with altitude, and height with diameter in breast height (dbh) of host had the highest significant positive correlation coefficient (0.67 and 0.64 respectively). On the other hand, host bark pH and altitude as well as land use had a significantly strong negative correlation coefficient (-0.80 and -0.61, respectively). Different epiphytic orchid species interact differently with the given set of environmental factors: for occurrence of Vanda cristata there is no single environmental factor of special influence, while for Rhynehostylis retusa high bark pH and high light availability are important. First two axis of the PCA explained more than 50% of the total variance. Most orchid species occupy a specific, narrow niche in this ecological space. The main causes of anthropogenie influence of orchid population in the Kathmandu Valley are loss of adequate host trees (species and size) and increasing air pollution, resulting in increasing host bark pH. 展开更多
关键词 Host characteristics Epiphytic orchids Anthropogenic disturbances Canopy ecosystem ecological niche HIMALAYAS
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Invasive sequence and ecological niche of main insect borers of Larix gmelinii forest in Aershan, Inner Mongolia 被引量:6
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作者 YUAN Fei LUO You-qing +5 位作者 SHI Juan Kari KELIOVAARA QI Guo-xin LI Xiang-jun HAN Yong-shi CHEN Chao 《Forestry Studies in China》 CAS 2008年第1期9-13,共5页
After the outbreak of Dendrolimus superans Buter in 2002, many insect borers quickly invaded larch (Larix gmelinii Rupr.) forests in the Aershan of Inner Mongolia. Methods involved included setting sample plots, col... After the outbreak of Dendrolimus superans Buter in 2002, many insect borers quickly invaded larch (Larix gmelinii Rupr.) forests in the Aershan of Inner Mongolia. Methods involved included setting sample plots, collecting adults in iron traps and measuring areas of galleries to study the invasive sequence, their ecological niche and the extent of the different effects by the main insect borers to their hosts. The results showed that the damage of D. superans weakened L. gmelinii, first Ips subelongatus Motschulsky invaded, followed by Acanthocinus carinulatus Gebler, Monochamus urussovi Fisher and M. sutor L. After the outbreak of D. superans, the average density of longhorn beetles per L. gmelinii tree increased. The ecological niche of Ips subelongatus stretches almost from the base to the top of the trunk. The number of insects in older stands of L. gmelinii is larger than those in middle aged stands. They do not damage healthy trees of L. gmelinii. The ecological niche of A. carinulatus is higher in dead L. gmelinii trees than in weak ones. The degree of damage is directly proportional with age and depth of bark. M. urussovi mainly damages trunks below 4 m in weak trees; in dead trees they can do damage up to 6 m in height. M. sutor mainly damages trunks below 5 m in weak L. gmelinii trees; in dead trees they cause damage up to 7 m. Again, the degree of damage is directly proportional with age. None of the three species of longhorn beetles damage healthy L. gmelinii and younger trees. Among the main insect borers, the degree of damage caused by I. subelongatus is more serious than that of other insects. 展开更多
关键词 Dendrolimus superans invasive sequence insect borer ecological niche damage degree
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Effects of dietary replacement of soybean meal with dried distillers grains with solubles on the microbiota occupying different ecological niches in the rumen of growing Hu lambs 被引量:2
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作者 Junshi Shen Zhipeng Li +1 位作者 Zhongtang Yu Weiyun Zhu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第2期677-688,共12页
Background:Diet has a profound impact on the rumen microbiota,and the impact can vary among the different rumen ecological niches(REN).This study investigated the effects of dietary replacement of soybean meal(SBM)wit... Background:Diet has a profound impact on the rumen microbiota,and the impact can vary among the different rumen ecological niches(REN).This study investigated the effects of dietary replacement of soybean meal(SBM)with dried distillers grains with solubles(DDGS)on the rumen microbiota occupying different REN of growing Hu lambs.After a 9-week feeding trial,6 lambs from each dietary treatment(SBM vs.DDGS-based diets)were slaughtered for sample collection.The microbiota of the rumen solid,liquid,and epithelium fractions was examined using amplicon sequencing analysis of bacterial 16S rRNA gene,functional prediction,and qPCR.Results:No interaction of dietary protein source(PS)and REN were detected for virtually all the measurements made in this study.The DDGS substitution resulted in very limited influence on bacterial community structure.However,the metabolic pathways predicted from 16S rRNA gene sequences varied greatly between SBM-and DDGS-based diets.The populations of rumen total bacteria,fungi,sulfate-reducing bacteria(SRB),and methanogens were not influenced by DDGS substitution,but the population of protozoa was reduced.The bacterial communities in rumen solid(RS)and liquid(RL)were similar in taxonomic composition but were different in relative abundance of some taxa.In contrast,the bacterial composition and relative abundance of rumen epithelium(RE)were greatly distinct from those of the RS and the RL.In alignment with the bacterial relative abundance,the metabolic pathways predicted from 16S rRNA genes also varied greatly among the different REN.The populations of total bacteria,protozoa,and methanogens attached to the RE were smaller than those in the RS and RL,and the fungal population on the rumen epitheliumwas smaller than that in the RS but similar to that in the RL.On the contrary,the SRB population on the RE was greater than that in the RS and RL.Conclusions:Substitution of SBM with DDGS had greater impact to the protozoa than to the other microbes,and the microbial community structure and functions at different REN are distinct and niche-adapted. 展开更多
关键词 Distillers dried grains with solubles Growing lamb MICROBIOTA Ruminal ecological niche Soybean meal
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Ecological Niche Modelling Reveals the Peculiarities of Ecological Disjunction Between Two Sympatric Racerunners in Kazakhstan:Eremias lineolata(Nikolsky,1897)and Eremias scripta(Strauch,1867)
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作者 Marina A.CHIRIKOVA Dmitry V.MALAKHOV 《Asian Herpetological Research》 SCIE CSCD 2023年第2期123-137,共15页
The ecological-niche models for two sympatric species,Eremias lineolata(Nikolsky,1897)and Eremias scripta(Strauch,1867),reveal evidence of spatial and temporal disjunction in the actual niches of both species.Eremias ... The ecological-niche models for two sympatric species,Eremias lineolata(Nikolsky,1897)and Eremias scripta(Strauch,1867),reveal evidence of spatial and temporal disjunction in the actual niches of both species.Eremias lineolata demonstrates a wide range of adaptations and,at the same time,has a greater need for winter precipitation and minimal temperature than E.scripta.Possible explanations for the thermal diversity of both species are provided.Thermal variables(monthly temperatures,monthly solar radiation,etc.)are traditionally important for ectotherm animals.Interestingly,as many as half of the key variables in both species are related to different aspects of environmental water balance(precipitation,air humidity,vapor pressure).There are several ways in which moisture may impact the lizard’s life cycle.Soil humidity is related to soil temperature and may be important during winter hibernation.In summer,soil humidity may support successful embryogenesis.Precipitation during the warm months is a key factor in maintaining the moisture content of the soil.In winter,snow cover provides a better thermal balance of the soil’s top layers where winter shelters are housed.Ecological niche modeling(ENM)is an interdisciplinary approach combining the geographical,climatic,ecological,and biological aspects of the wellbeing of species.This interdisciplinary approach lifts biological studies onto a new,integrative level,providing a comprehensive view on species biology and answering the questions that might not be answered if the traditional methods for studying animals were used alone. 展开更多
关键词 ECOLOGY Kazakhstan niche modelling racerunners species distribution
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The Empirical Study of Web-based Teacher's Ecological Niche
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作者 Sui Xiaobing Cheng Lulu 《学术界》 CSSCI 北大核心 2016年第5期262-268,共7页
Based on the previous research results and five principles,this paper tries to build an applicable optimization framew ork of college English classroom teaching,w hich centers on teacher development.According to this ... Based on the previous research results and five principles,this paper tries to build an applicable optimization framew ork of college English classroom teaching,w hich centers on teacher development.According to this framew ork,teacher development should include the modernized teacher development framew ork w ith the core ideas of optimizing the teachers’perception,teachers’information literacy,and diversified teaching methods,in w hich the concepts of teachers’self-development and life-long learning are emphasized.M oreover,the four important supporting contents w ere proposed:the teacher autonomy,the construction of intelligent teacher development platform,perfecting the training organization,and the informationization of teachers’training. 展开更多
关键词 教师培训 生态位 网络 研究成果 课堂教学 大学英语 教学方法 信息素养
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Prediction of Dry Dipterocarp Forest Distribution Using Ecological Niche Model in Ping Basin of Northern Thailand
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作者 Suwit Ongsomwang Yaowaret Jantakat 《Journal of Environmental Science and Engineering(B)》 2012年第5期636-643,共8页
DDF (dry dipterocarp forest) is importantly deciduous forest type in Thailand since it consists of important tree species for timber products and non-timber products. So, people would like to come to use these produ... DDF (dry dipterocarp forest) is importantly deciduous forest type in Thailand since it consists of important tree species for timber products and non-timber products. So, people would like to come to use these products for daily uses in this forest type. The main aim of this study is to evaluate significant biophysical factors for DDF distribution using factor analysis and to model DDF distribution using ENFA (ecological niche factor analysis). In this study, 13 watersheds of Ping Basin in northern Thailand were selected as the study site based on availability of forest inventory data in 2007 from DNP (Department of National Parks, Wildlife and Plant Conservation). Basic biophysical data for data analysis included forest inventory data (179 DDF plots), 10 climatic data, three topographic data, and one soil data. For identification and evaluation of biophysical factors for DDF distribution using factor analysis, the first three factors, namely DDF-1, DDF-2 and DDF-3, had been extracted with 95.35% of total variance. These three components were used to predict DDF distribution based on HS (habitat suitability) with ENFA. In practice, the results were validated with AVI (absolute validation index) and CVI (contrast validation index) with validated forest inventory dataset. This evaluation shows that DDF-2 model is the best HS data consisting of four physical factors (mean annually temperature, mean monthly maximum temperature, mean monthly minimum temperature, and elevation), which is able to effectively used for habitat suitability for DDF distribution prediction. It was found that habitat suitability for DDF distribution can be classified into four classes including high suitable habitat, moderate suitable habitat, low suitable habitat, and unsuitable habitat. As a result, DDF distributions with high suitable habitat are highly related with DDF forest inventory plots of DNP. Thus, the obtained output can be further used for DDF rehabilitation according to climate and topographic factors. 展开更多
关键词 Ping Basin of northern Thailand dry dipterocarp forest distribution prediction ENFA ecological niche factor analysis).
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Intra-tooth stable isotope analysis reveals seasonal dietary variability and niche partitioning among bushpigs/red river hogs and warthogs
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作者 Deming Yang Kevin T.Uno +4 位作者 Thure E.Cerling Ogeto Mwebi Louise N.Leakey Frederick E.Grine Antoine Souron 《Current Zoology》 SCIE CAS CSCD 2024年第6期739-751,共13页
How animals respond to seasonal resource availability has profound implications for their dietary flexibility and realized ecological niches.We sought to understand seasonal dietary niche partitioning in extant Africa... How animals respond to seasonal resource availability has profound implications for their dietary flexibility and realized ecological niches.We sought to understand seasonal dietary niche partitioning in extant African suids using intra-tooth stable isotope analysis of enamel.We collected enamel samples from canines of red river hogs/bushpigs(Potamochoerus spp.)and third molars of warthogs(Phacochoerus spp.)in 3 different regions of central and eastern Africa.We analyzed multiple samples from each tooth and used variations in stable carbon and oxygen isotope ratios(δ^(13)C andδ^(18)O)and covariances between them to infer seasonal dietary changes.We found that most Phacochoerus display C_(4)-dominated diets,while most Potamochoerus display C_(3)-dominated diets.Phacochoerus and Potamochoerus that co-occur in the same region display no overlap in intra-toothδ^(13)C,which suggests dietary niche partitioning.They also show divergingδ^(13)C values as the dry seasons progress and convergingδ^(13)C values during the peak of the rainy seasons,which suggests a greater dietary niche separation during the dry seasons when resources are scarce than during the rainy season.We found statistically significant cross-correlations between intra-toothδ^(13)C andδ^(18)O in most specimens.We also observed a temporal lag betweenδ^(13)C andδ^(18)O in some specimens.This study demonstrates that intra-tooth stable isotope analysis is a promising approach to investigate seasonal dietary niche variation.However,large inter-individual variations inδ^(18)O at certain localities can be challenging to interpret.Future studies that expand the intra-tooth stable isotope surveys or include controlled feeding experiments will improve its application in ecological studies. 展开更多
关键词 dietary ecology niche partitioning Phacochoerus Potamochoerus SEASONALITY
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寒区湖泊冰封期与非冰封期蓝藻群落特征分析
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作者 杨文焕 梁俊泓 +3 位作者 李艳芳 张明宇 王志超 李卫平 《湖泊科学》 EI CAS 北大核心 2025年第1期61-75,I0001,I0002,共17页
以蓝藻越冬的群落变化特征为基础,为揭示不同湖泊水生态变化,于2022年1月和7月在岱海、乌梁素海和南海湖共选取10个采样点采集上层水与底泥样品,开展了内蒙湖区不同类型湖泊冰封与非冰封时期蓝藻群落结构、丰度变化和多样性的研究。结... 以蓝藻越冬的群落变化特征为基础,为揭示不同湖泊水生态变化,于2022年1月和7月在岱海、乌梁素海和南海湖共选取10个采样点采集上层水与底泥样品,开展了内蒙湖区不同类型湖泊冰封与非冰封时期蓝藻群落结构、丰度变化和多样性的研究。结果表明:蓝藻经历了湖泊冰封期与非冰封期,丰度和多样性都发生了较大变化,可以很好地解释湖泊水生态变化情况,乌梁素海和南海湖非冰封期蓝藻丰度显著高于冰封期,而岱海因其湖泊水质的特殊性,冰封期水体蓝藻丰度显著高于非冰封期水体,而非冰封期底泥蓝藻丰度显著高于冰封期。不同时期不同湖泊蓝藻优势属的生态位宽度不尽相同,非冰封期和冰封期岱海和南海湖优势蓝藻普遍可利用多种资源,而乌梁素海优势蓝藻实际可利用资源较少。根据中性模型和冗余分析可知,非冰封期的乌梁素海和南海湖水体和底泥更多地受到随机过程的影响,相比之下,岱海底泥和南海湖水体则更多地受环境因素的制约;寒区湖泊蓝藻群落的组成、结构及影响因素存在季节差异,水温、总氮、氨氮和pH起到了关键作用。研究结果可为寒区湖泊水生态保护治理提供参考。 展开更多
关键词 寒区湖泊 蓝藻 群落结构 生态位 迁移
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基于生态位理论的区域可再生能源发电项目竞争格局研究——以蒙西地区为例
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作者 苑曙光 赵小溪 +2 位作者 郝晓燕 高松 李晗 《可再生能源》 北大核心 2025年第1期99-106,共8页
优化可再生能源发电项目规划布局,对推动区域可再生能源产业高质量发展具有重要意义。为了科学测量区域各类可再生能源发电项目的竞争力水平,文章基于生态位理论构建了区域可再生能源发电项目生态位宽度、强度以及重叠度模型,并以蒙西... 优化可再生能源发电项目规划布局,对推动区域可再生能源产业高质量发展具有重要意义。为了科学测量区域各类可再生能源发电项目的竞争力水平,文章基于生态位理论构建了区域可再生能源发电项目生态位宽度、强度以及重叠度模型,并以蒙西地区为例,结合2022年可再生能源发电项目运行数据,对各盟市风电以及太阳能发电项目生态位进行测度分析。结果表明:蒙西地区可再生能源发电项目生态位“结构”与“规模”宽度不匹配,须要持续优化乌兰察布和巴彦淖尔等地区可再生能源装机结构和规模;“呼包鄂乌”地区可再生能源生态位强度较低,未来应考虑重点发展分布式可再生能源发电项目;乌海与蒙西其他盟市的生态位重叠度较低,表明乌海地区拥有较强的可再生能源开发潜力。研究结果可为区域可再生能源规划提供理论支撑,同时也能为能源投资企业的项目开发提供决策依据。 展开更多
关键词 可再生能源发电 竞争力 生态位 项目规划
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基于MaxEnt模型的冬樱花潜在引种区研究
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作者 贺鹭瑶 徐晓丹 郑伟 《园林》 2025年第1期134-139,共6页
冬樱花(Cerasus cerasoides)是全球唯一在冬季盛开的樱花,主要分布于中国云南省,园林应用潜力巨大,但近年来冬樱花向省外的引种并不成功。因此,研究冬樱花在中国的潜在适生区对冬樱花园林引种和推广应用具有重要意义。收集冬樱花275个... 冬樱花(Cerasus cerasoides)是全球唯一在冬季盛开的樱花,主要分布于中国云南省,园林应用潜力巨大,但近年来冬樱花向省外的引种并不成功。因此,研究冬樱花在中国的潜在适生区对冬樱花园林引种和推广应用具有重要意义。收集冬樱花275个地理分布信息、32个环境变量因子以及当代(1970–2000年)、未来(2021–2070年)的气候数据,利用最大熵模型(MaxEnt)和地理信息系统(ArcGIS),预测当代和未来气候环境下冬樱花在中国的潜在引种区,并通过基于刀切法的ROC曲线对预测精度进行检验。影响冬樱花潜在引种区分布的主要环境因子包括:季节性温度变化、最干月降水量、等温性和海拔。预测模型的评估指标(AUC值)为0.983,表明预测精度极高,结果可靠。当前气候条件下,冬樱花引种区总面积为4.99×10^(5)km^(2),占中国陆地面积5.42%。其中,高、中、低引种区面积分别为2.04×10^(5)km^(2)(2.21%)、1.23×10^(5)km^(2)(1.24%)、1.81×10^(5)km^(2)(1.96%)。冬樱花潜在引种区主要分布在西南地区及华南地区。未来气候条件下,冬樱花的潜在引种区总面积呈增加趋势,适生区以高适生区为中心向四周扩散,尤其是东南方向。旨在为冬樱花的引种栽培、推广应用和区划研究提供参考。 展开更多
关键词 高盆樱桃 生态位模型 引种 适宜区 预测
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竞合视角下黄河流域城市群旅游竞争力提升分析
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作者 王冉 刘娜娜 《市场周刊》 2025年第1期73-76,98,共5页
黄河流域旅游高质量发展需要在城市群旅游差异化协同发展中寻求出路,文章从旅游竞合视角构建竞争力评价指标,计算黄河流域城市群旅游生态位,进而开展竞争力评价及空间格局分析。针对竞合现状,黄河流域城市群应做到多群互动,强化核心城... 黄河流域旅游高质量发展需要在城市群旅游差异化协同发展中寻求出路,文章从旅游竞合视角构建竞争力评价指标,计算黄河流域城市群旅游生态位,进而开展竞争力评价及空间格局分析。针对竞合现状,黄河流域城市群应做到多群互动,强化核心城市辐射力度,深入落实国家级战略,协作讲好新时代黄河故事,进一步创新驱动产业结构升级,构建城市群旅游内驱力,共同助力构建黄河生态带,推动区域旅游竞争力的提升。 展开更多
关键词 黄河流域城市群 生态位 旅游竞争力
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Potential distribution and ecological dimensions of four species in the genus Physopelta(Hemiptera:Largidae) 被引量:1
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作者 朱耿平 王晓静 +1 位作者 卜文俊 刘国卿 《Entomotaxonomia》 CSCD 北大核心 2012年第2期192-200,共9页
Our knowledge of the identity and distribution of most species on earth is remarkably poor. Species in hotspots tend to be scarce within their range which increases their probability of extinction. In this study, we u... Our knowledge of the identity and distribution of most species on earth is remarkably poor. Species in hotspots tend to be scarce within their range which increases their probability of extinction. In this study, we used ecological niche modeling (ENM) to estimate dimensions of realized niches of 4 species that are totally (Physopelta robusta St^l and Physopelta slanbuschii Fabricius) or partially (Physopelta cincticollis StS,1 and Physopelta quadriguttata Bergroth) distributed in the Indo-Myanmar and South Central China hotspot, and predicted additional sites where they might be found. Our findings suggest that the range of the 4 species could extend beyond their presently known distributions, which might be useful for future field surveys. Niche overlap was modeled between the 4 species, with R slanbuschii and R robusta showing more tolerance to temperature and P quadriguttata and P. slanbuschii more tolerance to precipitation. This study presents one more case study which highlights the ecological approach for taxonomic study in biodiversity conservation, especially of poorly, little known, and localized endemic species. 展开更多
关键词 HETEROPTERA Physopelta ecological niche modeling Indo-Myanmar hotspot South Central Chinahotspot insect conservation
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Study on Ecological Strategy of Enterprises' Competition 被引量:1
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作者 Xu Fang Li Jianhua +1 位作者 Ly Hong Zhang He 《Ecological Economy》 2005年第3期36-39,共4页
The ecolotogical research of enterprises' competition is the front line of current research of enterprises ' competition strategy : This text applies the competition principle of living creature in ecology to resea... The ecolotogical research of enterprises' competition is the front line of current research of enterprises ' competition strategy : This text applies the competition principle of living creature in ecology to research enterprises' competition problems .explains the ecological characterisiics of enterprises' competition, such as non-symmetry, crowded effect, density effect. competition-rejective effect, suitable resources niche and red queen effect etc., deduces the ecological model of enterprise' competition, and further analyzes enterprises' competition strategy; strategy R and strategy K. on the basis of enterprises' practices, Therefore enterprises' competition ecosystem theories have further been deepened and enriched. 展开更多
关键词 non-symmetry crowded effect competition-rejective effect niche ecosystem model ecological strategy
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Niche differentiation shapes the bacterial diversity and composition of apple
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作者 Yimei Huang Xiaofen Chai +7 位作者 Xiaona Wang Beibei Gao Hui Li Zhenhai Han Xuefeng Xu Xinzhong Zhang Ting Wu Yi Wang 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第1期35-44,共10页
Microorganisms play an important role in plant growth,health and ecological function.It is necessary to explore the microbial community because of the significant ecological and economic value of apples(Malus x domest... Microorganisms play an important role in plant growth,health and ecological function.It is necessary to explore the microbial community because of the significant ecological and economic value of apples(Malus x domestica).However,the related bacterial communities in different ecological habitats are not clear in the unique scion/rootstock combinations of apples.In this study,the Illumina Miseq platform was used to analyze the bacterial communities in different niches(bulk soil,rhizosphere soil and roots)of two scion/rootstock combinations[Fuji/Malus xiaojinensis Cheng et Jiang(Mx)and Fuji/Malus baccata(L.)Borkh.(Mb)].The relationship between the microbial community,soil properties,and plant characters was explored.The results showed that the diversity of the bacterial community decreased from bulk soil to rhizosphere soil and then to roots.In addition,at the phylum level,Proteobacteria,Actinobacteria and Acitinobacteria were dominant and had notable divergence in different ecological niches.Distinct niches had remarkable effects on the diversity and composition of the bacterial community according to PCoA.The rootstock genotype had an effect on the bacterial composition but no effect on the diversity.pH,soil organic matter(SOM),alkaline hydrolyzable nitrogen(AN)were the main factor affecting the structure of bacterial community in rhizosphere soil,as shown by Pearson analysis.Bacteria taxa in the roots were affected by starch,fructose,sucrose and sorbitol.This study showed the microbial community structure in different ecological niches of different scion/rootstock combinations and provided some evidence for understanding the microbial-plant interaction of apple rootstocks. 展开更多
关键词 APPLE Microbial community Rootstock genotype Ecology niche
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Ecological-Genetic Studies and Conservation of Endemic <i>Quercus sideroxyla</i>(Trel.) in Central Mexico
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作者 Cecilia Alfonso-Corrado Ricardo Clark-Tapia +5 位作者 Alejandro Monsalvo-Reyes Carlos Rosas-Osorio Gabriel González-Adame Francisco Naranjo-Luna Crystian-Sadiel Venegas-Barrera Jorge E. Campos 《Natural Resources》 2014年第9期442-453,共12页
This study examines the distribution, ecology and genetic diversity of Quercus sideroxyla Humb. Bonpl, with an emphasis on its conservation on the Natural Protected Area of Sierra Fría in North Central Mexico. Tw... This study examines the distribution, ecology and genetic diversity of Quercus sideroxyla Humb. Bonpl, with an emphasis on its conservation on the Natural Protected Area of Sierra Fría in North Central Mexico. Twenty-nine locations were selected, and in each location, one plot of 1500 m2 was established. At every location, we obtained an abundance of Q. sideroxyla and a basal area for each individual tree, including geographical and climatological data. We used the Outlying Mean Index (OMI) to examine whether environmental conditions had a distributional effect on Q. sideroxyla populations and to obtain the static size population structure of the species. For the genetic analysis, we collected 18 adult individuals from each population, four polymorphic loci were used to estimate genetic diversity. Q. sideroxyla abundance was associated with narrow environmental conditions, especially when considering the topographical and meteorological environmental variables. The allelic richness value was 84 alleles (21 privatealleles), and the expected mean heterozygosity was 0.855 ± 0.009. The high vulnerability of the species to changes in the land use at the local scale and to global climatic changes increases the species’ susceptibility to local disappearance. 展开更多
关键词 Ecology Genetic Diversity Local CONSERVATION niche OAKS
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Niche Characteristics of Herbaceous Plants under Pinus tabuliformis Plantation Forest in Feldspathic Sandstone Area
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作者 Cheng SUN Fucang QIN 《Asian Agricultural Research》 2021年第11期41-46,共6页
[Objectives] To explore the niche characteristics of herbaceous plants under Pinus tabuliformis plantation forest in the feldspathic sandstone area,and to provide basic data for maintaining biodiversity and community ... [Objectives] To explore the niche characteristics of herbaceous plants under Pinus tabuliformis plantation forest in the feldspathic sandstone area,and to provide basic data for maintaining biodiversity and community stability in the local P.tabuliformis plantation forest.[Methods] The types,quantity,average plant height,and coverage of various herbaceous plants were recorded by field survey in a well-growing P.tabulaeformis forest area.Based on the survey data,Shannon and Levins niche breadth index,Levins niche overlap index and ecological response were used to analyze the niche characteristics of herbaceous plants under P.tabulaeformis plantation forest.[Results]( i) There were 35 species of herbaceous plants in the P.tabulaeformis plantation forest in the feldspathic sandstone area.Among them,Stipa bungeiensis had the largest niche breadth indexes with better performance.Because of its strong adaptability,its community was in an obviously advantageous position.( ii) The overall niche width and niche overlap index were generally not high,and understory herb species showed differentiation.( iii) Among the understory herbaceous species,37.15% of the species were developed species,and 62.86% of the species were declining species.Among the 14 dominant species,11 were developmental species.The species with largest the resource occupancy were S.bungeiensis( 0.188 5),Heteropappus altaicus( 0.053 1),and Cleistogenes squarrosa( 0.037 9).[Conclusions] Competition among under herbaceous plants in P.tabulaeformis plantation forest in the feldspathic sandstone area was weak,and the community species had poor utilization of resources and environment.Most of the dominant herbaceous species were in the developing stage,indicating that the P.tabulaeformis plantation community tends to be relatively stable at the current stage. 展开更多
关键词 Feldspathic sandstone PLANTATION niche ecological response Herbaceous plants
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