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Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt
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作者 Asmaa S ABO HATAB Yassin M AL-SODANY +2 位作者 Kamal H SHALTOUT Soliman A HAROUN Mohamed M EL-KHALAFY 《Journal of Arid Land》 SCIE CSCD 2024年第7期1000-1021,I0002-I0044,共65页
Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emira... Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic species in Egypt, i.e., Ⅰ Asphodelus refractus group, Ⅱ Agathophora alopecuroides var. papillosa group, Ⅲ Anvillea garcinii group, Ⅳ Reseda muricata group, V Agathophora alopecuroides var. alopecuroides group, Ⅵ Scrophularia deserti group, and Ⅶ Astragalus schimperi group. It's crucial to clearly define the Saharo-Arabian endemics and illustrate an updated verified database of these taxa for a given territory for providing future management plans that support the conservation and sustainable use of these valuable species under current thought-provoking devastating impacts of rapid anthropogenic and climate change in this region. 展开更多
关键词 ENDEMISM phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)
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Water Quality Parameters and Fish Biodiversity Indices as Measures of Ecological Degradation: A Case Study in Two Floodplain Lakes of India 被引量:1
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作者 Debjit Kumar MONDAL Anilava KAVIRAJ Subrata SAHA 《Journal of Water Resource and Protection》 2010年第1期85-92,共8页
A three year study was conducted in two floodplain lakes to evaluate changes between seasonal variation of water quality parameter and finfish diversity indices. Samples of water and fish specimens were collected ever... A three year study was conducted in two floodplain lakes to evaluate changes between seasonal variation of water quality parameter and finfish diversity indices. Samples of water and fish specimens were collected every month from three different stations of each lake to determine physico-chemical parameters of water and the finfish diversity indices. Split-plot and MANOVA designs, Multiplicative decomposition method and quadratic regression analysis were used to analyze the effects of the rate of changes between the parameters and sustainability of the lakes. The obtained results suggested that the impact of environmental change (e.g depth, conductivity, salinity of water etc.) on diversity indices was significant and should be taken into consideration when designing policies to increase the long-term sustainability of fishing activities in the lakes. 展开更多
关键词 Baur FINFISH diversity indices MULTIPLICATIVE Decomposition QUADRATIC Regression
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Analysis on Nutritious Balance in Recipes Based on Diversity Indices and Cluster Analysis of Food Ingredients 被引量:1
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作者 Jiale Zhuang Junhui Gao 《Food and Nutrition Sciences》 2018年第7期834-839,共6页
This thesis research on nutritious balance of specific examples in Chinese recipes applying diversity indices and cluster analysis. Initially, based on data of the nutritional ingredients of food, such as proteins, fa... This thesis research on nutritious balance of specific examples in Chinese recipes applying diversity indices and cluster analysis. Initially, based on data of the nutritional ingredients of food, such as proteins, fat and vitamins, we categorize 1200 kinds of specific food using cluster analysis;then, according to a recipe given by a local restaurant, we calculate and compare the diversity indices based on the components of 25 single dishes in the recipe and analyze the nutritious balance of each dish. 展开更多
关键词 Components of FOOD Cluster ANALYSIS RECIPE NUTRITIOUS BALANCE diversity indices
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Plant Diversity as a Good Indicator of Vegetation Stability in a Typical Plateau Wetland 被引量:5
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作者 LI Wei TAN Rui +1 位作者 YANG Yu-ming WANG Juan 《Journal of Mountain Science》 SCIE CSCD 2014年第2期464-474,共11页
Biotic indicators have been widely used to monitor wetland health. However, few studies have explicitly evaluated if plant diversity could serve as a useful community-level indicator of wetland stability,especially wh... Biotic indicators have been widely used to monitor wetland health. However, few studies have explicitly evaluated if plant diversity could serve as a useful community-level indicator of wetland stability,especially when wetlands are confronted with anthropogenic perturbations. Based on three-year record of wetland plant species abundance in Napahai plateau wetland, Shangri-la under the influence of varying anthropogenic perturbation types, our study tests the impact of such perturbations on plant richness and the relationship between ecosystem temporal stability and plant richness, and further assesses the effectiveness of using plant diversity indicator to probe ecosystem temporal stability of Napahai plateau wetland and the potential mechanisms. The results showed that anthropogenic perturbations could have contributed significantly to realistic variation in plant diversity, and further demonstrated that ecosystem temporal stability was positively related to realistic variation in plant diversity. In particular, communities with high levels of diversity might have better capacity to dampen perturbation impacts than communities with low levels of diversity, and statistical averaging could have played an important role in causing greater stability in more diverse communities. Also, asynchrony might have a stabilizing effect on community stability, and diversity could have stabilized communities through both species asynchrony and population stability propagation. Therefore, our results suggest that plant diversity could be used as a useful indicator of the stability conditions of plateau wetland ecosystems confronted with anthropogenic perturbations, and the preservation of plant communities at sufficient abundance and diversity is necessary for maintaining healthy plateau wetlands and for sustaining their essential ecosystem functions and services. 展开更多
关键词 Plateau wetland Plant diversity Community stability Ecological indicator
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Quantifying Arborescent Flora Diversity in a Secondary Forest Ecosystem: A Comprehensive Assessment in Nambalan, Mayantoc, Tarlac, Philippines
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作者 Baby Jean L. Herbulario Raffy L. Tano Mileatte P. Omaney 《Open Journal of Ecology》 2023年第6期387-408,共22页
Forest plays a crucial role in providing essential ecosystem services, including water supply, climate regulation, and biodiversity conservation. This study aimed to assess the current state of the forest in Barangay ... Forest plays a crucial role in providing essential ecosystem services, including water supply, climate regulation, and biodiversity conservation. This study aimed to assess the current state of the forest in Barangay Nambalan, Mayantoc, Tarlac. The specific objectives were to identify tree species in the area and determine the tree diversity index, with a focus on endemism and conservation status. Two transect lines, each spanning one kilometer, were established and a total of 10 sampling quadrats were surveyed. Ecological parameters (relative frequency, relative density, relative dominance, and importance value index) and diversity indices (Shannon-Weiner index, Simpson’s index) were computed using the Paleontological Statistic Software Package for Educational Analysis (PAST 4.03). A comprehensive inventory revealed a total of 756 individuals representing 52 species, 46 genera, and 25 families. Among the recorded species, 10 (17.2%) were endemic and 11 (21.6%) were classified as threatened. The Fabaceae (20.8%), Moraceae (14.6%), and Euphorbiaceae (8.3%) were identified as the most abundant families. The computed diversity indices indicated that Barangay Nambalan retains a diverse forest cover;however, species composition was found to be relatively low. Based on the finding, this study recommends the strict enforcement of protective measures and legislation to mitigate further degradation of the remaining forest in Barangay Nambalan. 展开更多
关键词 Forest diversity Tree Species ENDEMISM Conservation Status Transect Survey diversity indices
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Exploratory analysis of structural diversity indicators at stand level in three Italian beech sites and implications for sustainable forest management
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作者 Giada Bertini Claudia Becagli +3 位作者 Ugo Chiavetta Fabrizio Ferretti Gianfranco Fabbio Luca Salvati 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第1期121-127,共7页
The present study introduces an exploratory data analysis based on structural indicators with the aim to assess the effect of silvicultural practices on tree stand structure. The study was carried out in three Italian... The present study introduces an exploratory data analysis based on structural indicators with the aim to assess the effect of silvicultural practices on tree stand structure. The study was carried out in three Italian beech forests of different ages with stand structures that originated from dissimilar regeneration and cultivation techniques(Cansiglio, northern Italy, Chiarano, central Italy,and Mongiana, southern Italy). Ten structural indicators were considered when investigating the latent multivariate relationship between stand structure attributes before and after thinning operations by using a multiway factor analysis(MFA). The MFA results identified the older stand at Cansiglio as more homogeneous for cultivation regimes,and more stable to practices when compared with the younger sites(Chiarano and Mongiana). Heterogeneous stands were sensitive to silvicultural practice thus suggesting their possible impact on forest attributes. The proposed approach proved to be an operational tool to evaluate comprehensively the response of forest structure to planned interventions. 展开更多
关键词 Forest diversity Multiway factor analysis SILVICULTURE Structural diversity indicATORS Tree STAND structure
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Simple Food Group Diversity as a Proxy Indicator for Iron and Vitamin A Status of Rural Primary School Children in Uganda
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作者 Hedwig Acham Gaston Ampek Tumuhimbise Joyce K. Kikafunda 《Food and Nutrition Sciences》 2013年第12期1271-1280,共10页
Children in resource poor settings are at a high risk of inadequate iron and vitamin A intake when diets lack diversity and are dominated by staple foods. Yet comparative information on diet quality among school child... Children in resource poor settings are at a high risk of inadequate iron and vitamin A intake when diets lack diversity and are dominated by staple foods. Yet comparative information on diet quality among school children is scarce. The objective of the study was to assess the potential of simple food group diversity to serve as a proxy indicator of iron and vitamin A status among rural school children in Uganda. A cross sectional correlation model of associations between Food Group Diversity (FGD) and iron and vitamin A status was used. We analyzed 8 schools in Kumi District, Uganda, randomly selected from the 34 schools that participated in the main part of the study. Our sample included primary school children, aged between 9-15 years (n = 172). Food group diversity and food variety (FV) were calculated from both a food frequency questionnaire (FFQ) and a 24-hour dietary recall. The FGD and FVS were tested against iron (as serum ferritin) and vitamin A (as serum retinol) status. The FGD (based on FFQ data) was 9.6 (±1.9). There was a positive correlation between 24-hour recall and FFQ for consumption of cereals (Corr. Coef = 0.28;p 0.05), which was also the most highly consumed group (98.9% & 86.9% by FFQ and 24-hour recall;respectively). Consistent with other studies, increase in the number of food groups significantly increased serum ferritin and serum retinol measures (p 0.001). Presence of at least one food item in the “roots & tubers”;“cereals”;and “pulses/nuts”, significantly increased serum ferritin and serum retinol concentrations (p 0.01). We speculate that simple food group diversity may reflect intake and serve as a simple indicator of iron and vitamin A status among school children. Strategies aimed at increasing dietary diversity in the community may benefit the families of these children and improve their micronutrient status. 展开更多
关键词 Food Group diversity IRON VITAMIN A PROXY indicATOR
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Addressing Biodiversity Conservation Methods with Fagus sylvatica Genetic Indicators
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作者 Giovanni Figliuolo 《Open Journal of Genetics》 2014年第2期166-174,共9页
Species biological history revealed by genetic indicators can provide guidelines for long-term biodiversity conservation in Natura 2000 network. Fagus sylvatica is the keystone species which regulates in the Mediterra... Species biological history revealed by genetic indicators can provide guidelines for long-term biodiversity conservation in Natura 2000 network. Fagus sylvatica is the keystone species which regulates in the Mediterranean Eco-Region ecosystem structure, function and composition. Six hundred fifty nine F. sylvatica individuals have been sampled across 20 sites of European interest in Southern Italy and analyzed at 5 microsatellite loci. For sites marked by both maximum heterozygosity (Ho) and minimum heterozygote deficit (Fis) (IT9210210, ITA070099, IT9210205 and IT9220075) it is suggested to avoid impacts by adopting very conservative measures. Promoting migration processes (pollen flow and seed flow) would be appropriate where it has been monitored low heterozygosity and high genetic disequilibrium. Margin effect due to dryness should be buffered with appropriate belts of thermophilus broad leaved tree species. 展开更多
关键词 Fagus sylvatica GENETIC diversity indicATOR Natura 2000
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Effects of long-term warming on the aboveground biomass and species diversity in an alpine meadow on the Qinghai-Tibetan Plateau of China 被引量:14
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作者 WEN Jing QIN Ruimin +2 位作者 ZHANG Shixiong YANG Xiaoyan XU Manhou 《Journal of Arid Land》 SCIE CSCD 2020年第2期252-266,共15页
Ecosystems in high-altitude regions are more sensitive and respond more rapidly than other ecosystems to global climate warming.The Qinghai-Tibet Plateau(QTP)of China is an ecologically fragile zone that is sensitive ... Ecosystems in high-altitude regions are more sensitive and respond more rapidly than other ecosystems to global climate warming.The Qinghai-Tibet Plateau(QTP)of China is an ecologically fragile zone that is sensitive to global climate warming.It is of great importance to study the changes in aboveground biomass and species diversity of alpine meadows on the QTP under predicted future climate warming.In this study,we selected an alpine meadow on the QTP as the study object and used infrared radiators as the warming device for a simulation experiment over eight years(2011-2018).We then analyzed the dynamic changes in aboveground biomass and species diversity of the alpine meadow at different time scales,including an early stage of warming(2011-2013)and a late stage of warming(2016-2018),in order to explore the response of alpine meadows to short-term(three years)and long-term warming(eight years).The results showed that the short-term warming increased air temperature by 0.31℃and decreased relative humidity by 2.54%,resulting in the air being warmer and drier.The long-term warming increased air temperature and relative humidity by 0.19℃and 1.47%,respectively,and the air tended to be warmer and wetter.The short-term warming increased soil temperature by 2.44℃and decreased soil moisture by 12.47%,whereas the long-term warming increased soil temperature by 1.76℃and decreased soil moisture by 9.90%.This caused the shallow soil layer to become warmer and drier under both short-term and long-term warming.Furthermore,the degree of soil drought was alleviated with increased warming duration.Under the long-term warming,the importance value and aboveground biomass of plants in different families changed.The importance values of grasses and sedges decreased by 47.56%and 3.67%,respectively,while the importance value of weeds increased by 1.37%.Aboveground biomass of grasses decreased by 36.55%,while those of sedges and weeds increased by 8.09%and 15.24%,respectively.The increase in temperature had a non-significant effect on species diversity.The species diversity indices increased at the early stage of warming and decreased at the late stage of warming,but none of them reached significant levels(P>0.05).Species diversity had no significant correlation with soil temperature and soil moisture under both short-term and long-term warming.Soil temperature and aboveground biomass were positively correlated in the control plots(P=0.014),but negatively correlated under the long-term warming(P=0.013).Therefore,eight years of warming aggravated drought in the shallow soil layer,which is beneficial for the growth of weeds but not for the growth of grasses.Warming changed the structure of alpine meadow communities and had a certain impact on the community species diversity.Our studies have great significance for the protection and effective utilization of alpine vegetation,as well as for the prevention of grassland degradation or desertification in high-altitude regions. 展开更多
关键词 climate WARMING LONG-TERM WARMING species diversity indices ABOVEGROUND biomass soil MICROCLIMATE correlation analysis ALPINE MEADOWS
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Reduction of Native Diversity by Invasive Plants Depends on Habitat Conditions 被引量:3
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作者 Yvonne Künzi Daniel Prati +1 位作者 Markus Fischer Steffen Boch 《American Journal of Plant Sciences》 2015年第17期2718-2733,共16页
Invasions by exotic plant species and their impacts on invaded communities are a highly topical field of research because it provides a basis for the management of neophyte populations. However, for many invasive neop... Invasions by exotic plant species and their impacts on invaded communities are a highly topical field of research because it provides a basis for the management of neophyte populations. However, for many invasive neophyte species in Central Europe little is known about their impacts on invaded plant communities. Moreover, it has hardly been considered whether effects vary among habitat conditions. Here, we selected each ten sites with different habitat conditions invaded by Erigeron annuus, Fallopia japonica, Impatiens glandulifera and Solidago canadensis which were listed as invasive in Switzerland. At each site, we established four 4 m × 1 m subplots covering a gradient from very low to very high cover of the particular neophyte species to investigate the effect of increasing neophyte cover on the species richness, Shannon diversity and evenness of the invaded plant communities. Moreover, we measured soil pH and characterized habitat conditions using Ellenberg indicator values to light and soil fertility. Whereas increasing cover of I. glandulifera had no effect on the diversity of invaded plant communities, an increasing cover of E. annuus negatively affected Shannon diversity. An increasing cover of F. japonica combined with a decreasing soil pH negatively affected the Shannon diversity of invaded plant communities. Similarly, an increasing cover of S. canadensis in combination with decreasing soil fertility negatively affected the Shannon diversity and evenness of invaded communities. Our results indicate that significant effects of increasing neophyte cover are mostly coupled to particular habitat conditions and then rather suppress than eliminate native plant species in invaded communities. We therefore suggest including abiotic variables in further impact studies on biotic invasions. Furthermore, adapting measures to the respective environmental context can be a useful tool in priority setting for the management of invasive neophyte populations and the restoration of invaded habitats. 展开更多
关键词 diversity Impact of NEOPHYTES indicATOR VALUES Plant SPECIES Richness
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Phylogeny Constructed by Using Diversity Increment 被引量:1
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作者 Shi Feng, Li Na-na, Li Yuan-xiang, Zhou Huai-beiSchool of Mathematics and Statistics, Wuhan University, Wuhan 430072,Hubei,ChinaAdvanced Research Center for Science and Technology, Wuhan University, Wuhan 430072, Hubei,ChinaState Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072,Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第S1期303-306,共4页
A new approach based on the concept of the diversity increment is applied to reconstruct a phylogeny. The phylogeny of the Eutherian orders use concatenated H-stran-ded amino acid sequences, and the result is consiste... A new approach based on the concept of the diversity increment is applied to reconstruct a phylogeny. The phylogeny of the Eutherian orders use concatenated H-stran-ded amino acid sequences, and the result is consistent with the commonly accepted one for the Eutherians. 展开更多
关键词 diversity indicator PHYLOGENY DISTANCE
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Impact of Removal of Copper Leaf (<i>Acalypha fruticosa</i>Forssk.) on Plant Species Diversity and Abundance at Chemeron, Baringo County, Kenya 被引量:1
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作者 George Morara Ogendi Rhoda N. Ondieki Tabitha W. Njoroge 《Open Journal of Ecology》 2020年第6期341-355,共15页
Invasive plant species may significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. Their impacts on plant communities may be both direct and indirect. ... Invasive plant species may significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. Their impacts on plant communities may be both direct and indirect. The direct effects may include a reduction in the abundance and diversity of palatable plant species that constitute important forage for livestock, wildlife, and medicines for the local communities. Declines in ecosystem resilience are of the notable indirect effects of invasive species. The aim of this study was to assess the impacts of a plant species, copper leaf (<em>Acalypha fruticosa</em>) on floral diversity and abundance at Chemeron, Baringo County in Kenya. The study was guided by three questions: What is the plant composition in terms of grasses, herbs, shrubs, and trees in the study area? Are there any variations in plant abundance between the two sites (sites with and without <em>Acalypha fruticosa</em>)? Are there variations in plant species diversity between the two study sites? Two sites (one with <em>A. fruticosa</em> and another two without this invasive species) were selected within the Chemeron Research Centre. Two belt transects measuring 100 m × 20 m on each site were laid parallel to each other. Plant samples were collected from five 1 m × 1 m quadrats that were laid at intervals of 20 m. The plant species or specimens were identified to the species level using available taxonomic keys. Various indices including Shannon-Wiener (<em>H</em>’), Evenness Index, Richness Index and Simpson’s Index of Diversity Index (SDI) were calculated. All the diversity, richness and evenness indices were considerably higher in the site without <em>A. fruticosa</em> compared to that where this invasive species was present. Higher <em>H’</em> (3.14 to 3.21) and SDI (0.93 to 0.94) values were noted in sites without the invasive species compared to <em>H</em>’ (2.11 to 2.20) and SDI (0.77 to 0.85) in sites with <em>A. fruticosa</em> present. Out of the 47 plant species identified, 39 and 20 of them occurred in the site without and with <em>A. fruticosa</em>, respectively. Further, there were more grasses (<em>Aristida keniensis</em>, <em>Cynodon dactylon</em>, <em>Brachiaria lucrantha</em>, <em>Eragrostis racemosa</em>, and <em>Enteropogon macrostachyus</em>) in the site without <em>A. fruticosa</em> compared to that with the invasive plant. The plants were also more evenly distributed in the site without <em>A. fruticosa</em> compared to that where the invasive plant was present. We conclude that <em>A. fruticosa</em> has a significant effect on plant species abundance and diversity as well as distribution. Its removal created a favourable environment for the growth of a variety of grasses. We therefore recommend to the agro-pastoralists and rangeland managers that <em>A. fruticosa</em> be mechanically removed by uprooting from grazing lands so as to increase forage availability and quality in the rangelands of South-Baringo. 展开更多
关键词 Baringo Copper Leaf diversity indices Invasive Species Plant diversity
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Relationship of species diversity between overstory trees and understory herbs along the environmental gradients in the Tianshan Wild Fruit Forests, Northwest China 被引量:1
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作者 CHENG Junhui SHI Xiaojun +3 位作者 FAN Pengrui ZHOU Xiaobing SHENG Jiandong ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2020年第4期618-629,共12页
In forest ecosystems, interactions between overstory trees and understory herbs play an important role in driving plant species diversity. However, reported links between overstory tree and understory herb species div... In forest ecosystems, interactions between overstory trees and understory herbs play an important role in driving plant species diversity. However, reported links between overstory tree and understory herb species diversity have been inconsistent, due to variations in forest types and environmental conditions. Here, we measured species richness(SR) and diversity(Shannon-Wiener(H') and Simpson's(D) indices) of overstory trees and understory herbs in the protected Tianshan Wild Fruit Forest(TWFF), Northwest China, to explore their relationships along the latitudinal, longitudinal, elevational, and climatic(current climate and paleoclimate) gradients in 2018. We found that SR, and H' and D diversity indices of overstory trees and understory herbs exhibited a unimodal pattern with increasing latitude and elevation(P<0.05) and negative associations with longitude(P<0.01). Along the climatic gradients, there were U-shaped patterns in SR, and H' and D diversity indices between trees and herbs(P<0.05). SR, and H' and D diversity indices for overstory tree species were positively associated with those for understory herbs(P<0.01). These findings indicate that overstory trees and understory herbs should be protected concurrently in the TWFF to increase effectiveness of species diversity conservation programs. 展开更多
关键词 diversity indices overstory trees understory herbs PALEOCLIMATE current climate elevation
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Plant diversity at Chilapatta Reserve Forest of Terai Duars in subhumid tropical foothills of Indian Eastern Himalayas
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作者 Gopal Shukla Rajib Biswas +1 位作者 A. P. Das Sumit Chakravarty 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第3期591-596,共6页
From March 2007 to March 2009 we quantified plant diversity at Chilapatta Reserve Forest in Terai Duars in the Indian eastern Himala-yas. We sampled stratified random nested quadrats. Species richness was 311, represe... From March 2007 to March 2009 we quantified plant diversity at Chilapatta Reserve Forest in Terai Duars in the Indian eastern Himala-yas. We sampled stratified random nested quadrats. Species richness was 311, representing 167 genera and 81 families. The species diversity index and concentration of dominance of the forest were 2.20 and 0.0072, respectively. Shannon-Wiener index and evenness indices were 4.77 and 1.44, respectively. The Importance Value Index (IVI) of species ranged from 0.13 to 37.94. The estimated diversity indices indicated heterogene-ity of the forest in its composition, structure, function and dynamics. Rich forest plant diversity supports the need for continued conservation of tropical forests. 展开更多
关键词 Terai Duars phyto-sociology plant diversity diversity indices
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A Review of Water Quality Indices Used to Assess the Health Status of High Mountain Wetlands
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作者 María Custodio 《Open Journal of Ecology》 2019年第3期66-83,共18页
The health status of wetlands depends to a large extent on the permanence and quality of water. However, natural and anthropogenic pressures on these ecosystems are transforming them and driving them to generate timel... The health status of wetlands depends to a large extent on the permanence and quality of water. However, natural and anthropogenic pressures on these ecosystems are transforming them and driving them to generate timely and reliable information. The aim of this study is to provide a review of water quality indices used to assess the health status of high mountain wetlands. To this end, an exhaustive search was initially carried out for studies with significant contributions to the knowledge of high mountain wetlands in Peru. In total, 90 articles on wetlands published in the last decade (2007-2017) were reviewed through bibliographic managers, of which 25% corresponded to wetland studies in Peru and of these only 6% to water quality in high Andean wetlands. 展开更多
关键词 Water Quality Biotic indices diversity indices CONVENTIONAL indices Sustainable Management
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Floristic diversity and structural parameters of the Brazzaville Patte d’Oie forest, Congo
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作者 Victor Kimpouni Paul Mbou +1 位作者 Ernest Apani Marcel Motom 《Open Journal of Ecology》 2013年第8期518-531,共14页
The flora of the Patte d’Oie forest of Brazzaville is studied according to three plots of 0.5 ha, corresponding each to one of the islet, currently constituting it. With an original area of 240 ha, put in reserve in ... The flora of the Patte d’Oie forest of Brazzaville is studied according to three plots of 0.5 ha, corresponding each to one of the islet, currently constituting it. With an original area of 240 ha, put in reserve in 1938, the natural forest of the Patte d’Oie of Brazzaville covers 95 ha, less than 39% compared to initial area. Because the other main forests of Brazzaville have disappeared without delivering their biodiversity, this study is the first one which emphasizes the flora of this single ecosystem of Congo. The total floristic inventory revealed 459 trees of dbh≥10 cm on 1.5 ha;it is an average of 306 trees?ha?1. 31 species are listed for 17 families, and the best represented of which (Fabaceae, Euphorbiaceae and Rubiaceae) have a diversity varying from 13% to 19% of the inventory and a tree number oscillating from 15% to 36%. The Shannon (H') biological diversity index of the three plots is of 2.6 on average, for a maximum diversity (H'max) average of 2.9 versus an average true diversity of 15. The Pielou index is on average 0.9, whereas that of Simpson is 0.9. The coefficients of similarity of Jaccard (41.4% to 57.1%) and of the coefficient of S?rensen (58.5% to 72.7%) show the variations in the floristic composition. The followed ecological parameters show that this ecosystem is very few diversified compared to the tropical wet dense forests on the one hand, and, on the other hand, a non constant floristic composition is not. The analysis of the diametric structure by plot and the dominant and/or characteristic species give erratic curves, evidence of an insufficiency of the regenerative potential. Indeed, approximately 70% of the species are characteristic of the disturbed ecosystems (Macaranga sp.,Caloncoba welwitschii,Hymenocardia ulmoides,and Anthocleista sp.). 展开更多
关键词 CONGO FLORISTIC diversity Biological diversity indices Population Structure Urban FOREST RESERVE
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Influence of soil and elevation on roadside cryptogam diversity in the tropical Andes
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作者 Paul Salinas Marina Mazon +4 位作者 Vinicio Carrion-Paladines Nixon Cumbicus Patricio Guzman Paolo Giordani Angel Benítez 《Forest Ecosystems》 SCIE CSCD 2022年第5期639-646,共8页
Background: The deforestation caused by road construction is one of the main drivers for both biodiversity and function loss in tropical ecosystems. Terricolous cryptogams are pioneers in colonizing roadside and they ... Background: The deforestation caused by road construction is one of the main drivers for both biodiversity and function loss in tropical ecosystems. Terricolous cryptogams are pioneers in colonizing roadside and they are limited by environmental and edaphic factors, thus, cryptogams may act as pioneers for ecosystem rehabilitation at roadside.Methods: This research was aimed at determining the diversity and composition of terricolous cryptogams, as well as their relationship with elevation and soil properties among roadside of the tropical Andes of Ecuador, in order to establish indicator species of this anthropized ecosystems. Five elevations were selected and in each one 50grids of 20 cm×30 cm were sampled(250 in total along the road), where occurrence, cover and identification of every cryptogam species were recorded. To evaluate the effect of elevation and soil properties on cryptogam richness, a linear model was conducted. Species composition among elevations was compared by non-metric multidimensional scaling(NMDS), and their relationship with the environmental variables through a correlation with adjusted axes was performed. A total of 72 species were recorded, those being 44 bryophytes and 28lichens. Species richness and composition of terricolous cryptogams were influenced by elevation and soil properties, thus the richness is higher at elevations E1, E2 and E3(2600, 2200 and 1800 m a.s.l.), differing from low elevations E4 and E5(1400 and 1000 m a.s.l.). Higher elevations with specific soil conditions(e.g bulk density, nitrogen and silt) harbored different cryptogam communities than those in lower elevations.Conclusions: A combination of both elevation and soil properties are shaping the colonization by terricolous cryptogams commnunities. As such, 18 species were identified as the best indicators for all sets of environmental conditions at the roadside, which can therefore be considered for monitoring ecological processes in tropical areas. Use of biocrusts for restoration is an emerging field. If implemented in the study region, elevation and soil drivers may help to better chose the more suitable cryptogam species to manage and stabilize roadside in tropical roads. 展开更多
关键词 BRYOPHYTES indicator species Beta diversity LICHENS Richness Ecuador
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Seasonal species Diversity of Phytoplankton in Zhangjiang Seawaters
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作者 LIU YU 《生物多样性》 CAS CSCD 1994年第B11期36-42,共7页
关键词 浮游植物 生物多样性 红潮海藻 优势种群 季节
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Butterfly Diversity in Relation to Human-Impact Gradient in Out-skirts of Kolkata,West Bengal,India
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作者 Kaiyum Baskh Mollah Sudipta Mandal 《Research in Ecology》 2022年第4期1-12,共12页
Anthropogenic activities may affect species diversity and community structure.Butterfly species diversity in relation to human-impact gradient was evaluated in the Baruipur subdivision,outskirts of Kolkata metropolis,... Anthropogenic activities may affect species diversity and community structure.Butterfly species diversity in relation to human-impact gradient was evaluated in the Baruipur subdivision,outskirts of Kolkata metropolis,West Bengal,India as a model geographic area.Four study sites situated in bird sanctuaries,rural,suburban and urban areas with different levels of anthropogenic disturbances were selected to assess the human impact on butterfly diversity.A total of 80 butterfly species were recorded during the entire study period with the sanctuary(with minimal anthropogenic disturbance)showing the highest species richness(73)followed by rural(62),suburban(54)and urban(36)study sites indicating a strong negative impact of anthropogenic disturbance on butterfly species diversity.Butterfly species diversity varied significantly among different habitats(p˂0.001).The relative abundance of butterflies also varied seasonally.It is apparent that the area under the present study is able to sustain diverse butterfly species provided natural habitats are protected from anthropogenic disturbances and steps are taken to increase urban greenery to support butterfly diversity and consequent ecosystem services. 展开更多
关键词 Butterfly diversity Human-impact gradient Baruipur subdivision KOLKATA diversity indices
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MaOEA/I:Many-objective Evolutionary Algorithm Based on Indicator I_(ε+)
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作者 Sifeng Zhu Chengrui Yang Jiaming Hu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第5期52-64,共13页
Balancing the diversity and convergence of the population is challenging in multi-objective optimization. The work proposed a many-objective evolutionary algorithm based on indicator I_(ε+)(MaOEA/I) to solve the abov... Balancing the diversity and convergence of the population is challenging in multi-objective optimization. The work proposed a many-objective evolutionary algorithm based on indicator I_(ε+)(MaOEA/I) to solve the above problems. Indicator I_(ε+)(x,y) is used for environmental selection to ensure diversity and convergence of the population. I_(ε+)(x,y) can evaluate the quality of individual x compared with individual y instead of the whole population. If I_(ε+)(x,y) is less than 0, individual x dominates y. If I_(ε+)(x,y) is 0, individuals x and y are the same. If I_(ε+)(x,y) is greater than 0, no dominant relationship exists between individuals x and y. The smaller I_(ε+)(x,y), the closer the two individuals. The dominated individuals should be deleted in environmental selection because they do not contribute to convergence. If there is no dominant individual, the same individuals and similar individuals should be deleted because they do not contribute to diversity. Therefore, the environmental selection of MaOEA/I should consider the two individuals with the smallest I_(ε+)(x,y). If I_(ε+)(x,y) is not greater than 0, delete individual y;if I_(ε+)(x,y) is greater than 0, check the distance between individuals x, y, and the target point and delete the individual with a longer distance. MaOEA/I is compared with 6 algorithms until the population does not exceed the population size. Experimental results demonstrate that MaOEA/I can gain highly competitive performance when solving many-objective optimization problems. 展开更多
关键词 many-objective evolutionary algorithm indicATOR diversity CONVERGENCE
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