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Predicting changes in the suitable habitats of six halophytic plant species in the arid areas of Northwest China
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作者 YANG Ao TU Wenqin +9 位作者 YIN Benfeng ZHANG Shujun ZHANG Xinyu ZHANG Qing HUANG Yunjie HAN Zhili YANG Ziyue ZHOU Xiaobing ZHUANG Weiwei ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2024年第10期1380-1408,共29页
In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of... In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China. 展开更多
关键词 HALOPHYTES climate change global warming maximum entropy(MaxEnt)model soil salinization suitable habitats Northwest China
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Propagation Dynamics of Forced Pulsating Waves for a Time Periodic Lotka-Volterra Cooperative System with Nonlocal Effects in Shifting Habitats
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作者 Zewen Gong 《Journal of Applied Mathematics and Physics》 2024年第10期3402-3421,共20页
In this paper, we will concern the existence, asymptotic behaviors and stability of forced pulsating waves for a Lotka-Volterra cooperative system with nonlocal effects under shifting habitats. By using the alternativ... In this paper, we will concern the existence, asymptotic behaviors and stability of forced pulsating waves for a Lotka-Volterra cooperative system with nonlocal effects under shifting habitats. By using the alternatively-coupling upper-lower solution method, we establish the existence of forced pulsating waves, as long as the shifting speed falls in a finite interval where the endpoints are obtained from KPP-Fisher speeds. The asymptotic behaviors of the forced pulsating waves are derived. Finally, with proper initial, the stability of the forced pulsating waves is studied by the squeezing technique based on the comparison principle. 展开更多
关键词 Nonlocal Effects Time Periodic Lotka-Volterra System Forced Pulsating Waves Shifting habitats
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Assessment of the Characteristics of Demersal Fish Communities Using Species-and Trait-Based Approaches in the Coastal Habitats Along Rongcheng Bay,Shandong Peninsula,China
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作者 YUAN Shunjie SUN Xin +3 位作者 TU Zhong SUN Jie WANG Xianning ZHANG Peidong 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期786-796,共11页
Biodiversity declines have motivated many studies on the relationship between species diversity and ecosystem functioning.In this study,we described the spatial-temporal characteristics of demersal fish communities al... Biodiversity declines have motivated many studies on the relationship between species diversity and ecosystem functioning.In this study,we described the spatial-temporal characteristics of demersal fish communities along a coastal habitat in Rongcheng Bay,Shandong Peninsula,China with both species-based and biological trait-based approaches.The field survey was carried out monthly using traps from April to October of 2018,and divided into three seasons(spring:April and May;summer:June,July and August;autumn:September,October and November).The study area included five distinct habitats:seagrass bed,natural rocky reef,bare sand,artificial reef together with natural rocky reef,and artificial reef together with bare sand.We analyzed the fish communities with three taxonomic diversity indices,including Shannon-Wiener,Simpson,and Pielou Evenness,as well as four functional diversity indices,including FRic,FEve,FDiv,and FDis,based on 7 functional groups which are categorized into 27 traits.The results showed that there were no significant differences in taxonomic diversity indices among different habitats in the three seasons.However,significant differences were found in the functional richness of fish communities among different habitats in three seasons.Seagrass bed represented the highest functional richness in spring and autumn.This study demonstrates that seagrass bed is very important in enhancing the functional diversity of fish communities in a complex habitat.The study also indicates that the combination of taxonomic diversity and functional diversity will provide a more detailed description of the characteristics of fish communities. 展开更多
关键词 complex habitat biological traits BIODIVERSITY fish communities
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Designated critical habitats for U.S.imperiled species are not protected from climate and land-use change
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作者 Aimee Delach Laura A.Nunes +1 位作者 Alex Borowicz Theodore C.Weber 《Geography and Sustainability》 CSCD 2024年第3期482-490,共9页
Designation of critical habitat is an important conservation tool for species listed as threatened or endangered under the United States(U.S.)Endangered Species Act(ESA).While this is an important protective mechanism... Designation of critical habitat is an important conservation tool for species listed as threatened or endangered under the United States(U.S.)Endangered Species Act(ESA).While this is an important protective mechanism,lands designated as critical habitat could still be subject to degradation and fragmentation if they are not also in a protected status that prioritizes biodiversity conservation.Additionally,most designations of critical habitat do not explicitly take climate change into account.The objective of our study was to determine whether and to what extent critical habitats for species listed under the ESA are located within protected areas and areas previously identified as climate refugia or climate corridors,to inform management strategies to better conserve and recover these species.We mapped the designated critical habitats of 153 ESA-listed species and measured their overlap with previously-identified areas of climate refugia and corridors(CRC),and also with lands designated as nature-protected by U.S.Geological Survey’s Gap Analysis Project(GAP Status 1 or 2)and working lands with wildlife habitat potential(GAP Status 3).Only 18%of all designated critical habitat is located on lands that are both in CRC and nature-protected,and only 9%of species had over half of their designated critical habitats in such lands.84%of species had<25%overlap of their critical habitats with these areas.Critical habitats may therefore not fulfill their essential role of helping imperiled species persist and recover. 展开更多
关键词 Endangered Species Act Critical habitat Climate refugia Climate corridors Protected areas Biodiversity conservation
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Diversity and Adaptations of Immature Diptera in Semiaquatic Habitats at Shorelines of Hypersaline Lakes in the Crimea,with a Brief Review of Diptera in Mineralized Bodies of Water
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作者 Andrey PRZHIBORO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期98-100,共3页
The order Diptera(Insecta)is one of animal groups most successful in the colonization of mineralized shallow aquatic and semiaquatic environments.At the same time,the taxonomic composition of Diptera,their role in
关键词 salt lakes mineralized bodies of water aquatic habitats shoreline semiaquatic habitats DIPTERA larvae biodiversity community taxonomic richness ADAPTATIONS heat shock proteins.
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Determination of Poliumoside and Forsythoside B in Different Parts of Callicarpa kwangtungensis and Its Plants from Different Habitats 被引量:1
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作者 李开斌 孙刚 +2 位作者 马四补 晏晨 李春植 《Agricultural Science & Technology》 CAS 2016年第5期1080-1082,1088,共4页
[Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components(poliumoside and forsythoside B... [Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components(poliumoside and forsythoside B) in the plant and to compare the contents of these components in the medicinal materials from different habitats.[Methods] Comparison and analysis of the contents of the two target components in different parts(root,branch,leaf and fruit) of Callicarpa kwangtungensis from the same habitat and in Callicarpa kwangtungensis from different production areas were performed according to the pharmacopoeia standard.[Result]The highest content of poliumoside wasdetected in fruit,and the content of forsythoside B was the highest in the branch.The contents of the two kinds of components were in order of branch fruit leafroot;The contents of the components were four times higher than China pharmacopeia(0.5%) in Jian,Tonggu,Anyuan,and Ganzhou of Jiangxi Province and the fifth area,Taijiang County of Qiandongnan Miao and Dong Autonomous Prefecture(QMDAP),among which Ganzhou and Taijiang showed the highest contents.[Conclusion] The differences of poliumoside and forsythoside B were obvious in different habitats and different parts of Callicarpa kwangtungensis. 展开更多
关键词 Callicarpa kwangtungensis CONTENTS Different habitats Different parts
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The possibility analysis of habitats,origin and reappearance of bloom green alga(Enteromorpha prolifera) on inshore of western Yellow Sea 被引量:12
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作者 丁兰平 费修绠 +2 位作者 陆勤勤 邓蕴彦 连绍兴 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期421-424,共4页
Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible w... Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible water area in China producing a large biomass,some reasons for firestorm,and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera.The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons.It was transferred northward by the combination of the flow of rainwater,wind and alongshore marine current.The original region of large biomass produced is possibly located in the southwestern Yellow sea.It will possibly be appearing again in the coming years or in the future.A summary is also given referring to its reproduction,development and distribution worldwide. 展开更多
关键词 bloom green alga Enteromorpha prolifera ORIGIN habitats reappearance western Yellow Sea
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Modeling foraging habitats of Hume’s Pheasant (Syrmaticus humiae) in Dazhong Mountain, Yunnan, southwestern China 被引量:5
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作者 周伟 李宁 +3 位作者 邓忠坚 张庆 李明会 王学荣 《Chinese Birds》 2010年第4期236-243,共8页
We modeled foraging habitats of Hume’s Pheasant (Syrmaticus humiae) on a macro-habitat level using ArcGIS in an attempt to provide scientific reference for management and restoration of habitats. Field work was condu... We modeled foraging habitats of Hume’s Pheasant (Syrmaticus humiae) on a macro-habitat level using ArcGIS in an attempt to provide scientific reference for management and restoration of habitats. Field work was conducted from March to April in 2006 and 2008, and from October to November in 2005 and 2008 in Dazhong Mountain, Yunnan Province, southwestern China. The selection of ecological factors was estimated by means of a resource selection index, distance analysis and the method of hierarchical habitat selection. The foraging habitat patches were modeled spatially by ArcGIS. The results show that actual and potential foraging patches overlapped considerably in spring and autumn. The number and total areas of patches in the autumn were smaller than those in the spring. The minimum and average areas of patches in the autumn were larger than those in the spring, while the maximum areas of actual and potential foraging patches in the autumn were equal to those in the spring. Similarity in the selection for survival and safety consideration in both seasons was the main strategy for landscape factors of habitats by Hume’s Pheasant, while seasonal difference in selecting a landscape matrix was their secondary strategy, affecting landscape factors in the habitat. Changes of foraging patches in both seasons reflect a difference of resources requirement by the bird. Fragmentation and miniaturization of foraging patches would result in the formation of a meta-population of Hume’s Pheasant. 展开更多
关键词 Hume’s Pheasant (Syrmaticus humiae) foraging strategy habitat modeling habitat patch
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Protection and Construction Measures of Wild Animals' Habitats in Ecological Green Land Design in Town-and-City Concentration Areas of China
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作者 凌静 吴迪 +2 位作者 辜彬 王思麒 罗言云 《Journal of Landscape Research》 2012年第5期61-64,共4页
Town-and-city concentration area is confronted with ecological degeneration due to the expansion of urbanization,and enriching urban bio-diversity is conducive to the improvement of ecological function of urban green ... Town-and-city concentration area is confronted with ecological degeneration due to the expansion of urbanization,and enriching urban bio-diversity is conducive to the improvement of ecological function of urban green system.The paper has studied how to increase urban bio-diversity by making use of urban green lands for protection and construction of wild animals' habitats,and proposed the significance and theoretical idea for protection and construction of wild animals' habitats.By taking ecological green lands design in Qinglongchang of Chengdu City for example,it has analyzed the current situation of animals' diversity;proposed to plan corridor,construct biological channel and provide multiporous habitats;listed plants' selection and collocation mode;and finally illustrated how to set artificial facilities for attraction of animals.It hopes to provide a reference for the design of ecological green lands in cities advocating the harmonious development of living environment and natural environment. 展开更多
关键词 Wild animals’ habitats ECOLOGICAL green lands Town-and-city CONCENTRATION area
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Environmental characteristics of anopheline mosquito larval habitats in a malaria endemic area in Iran 被引量:2
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作者 Moussa Soleimani-Ahmadi Hassan Vatandoost +4 位作者 Ahmad-Ali Hanafi-Bojd Mehdi Zare Reza Safari Abdolrasul Mojahedi Fatemeh Poorahmad-Garbandi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第7期510-515,共6页
Objective:To determine the effects of environmental parameters of lanal habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran.Methods:This cross-sectional study was conducted during t... Objective:To determine the effects of environmental parameters of lanal habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran.Methods:This cross-sectional study was conducted during the mosquito breeding season from February 2010 to October 2011. The anopheline larvae were collected using the standard dipping method,the specimens were identified using a morphological-based key.Simultaneously with larvay collection,environmental parameters of the larval habitats including water current and turbidity,sunlight situation,and substrate type of habitats were recorded.Water samples were taken from breeding sites during lanal collection.Before collection of samples,the water temperature was measured.The water samples were analysed for turbidity,conductivity,total alkalinity,total dissolved solid.pH and ions including chloride,sulphate,calcium,and magnesium.Statistical correlation analysis and ANOVA test were used to analyze the association between environmental parameters and larval mosquito abundance.Results:In total 2 973 lanae of the genus Anopheles were collected from 25 larval habitats and identified using morphological characters.They comprised of six species: An.dthali(53.21%),An.stephensi(24.22%),An.culicifacies(14.06%),An.superpictus(4.07%),An. turkhudi(3.30%),and An.apoci(1.14%).The most abundant species was An.dthali which were collected from all of the study areas.Larvae of two malaria vectors.An.dthali and An.stephensi, co-existed and collected in a wide range of habitats with different physico-chemical parameters. The most common larval habitats were man-made sites such as sand mining pools with clean and still water.The anopheline mosquitoes also preferred permanent habitats in sunlight with sandy substrates.The results indicated that there was a significant relationship between mean physicochemical parameters such as water temperature,conductivity,total alkalinity,sulphate,chloride, and mosquito distribution and abundance.Conclusions:The results of this study showed a correlation between certain environmental parameters and mosquito lanae abundance,and these parameters should be considered in planning and implementing larval control programs. 展开更多
关键词 ANOPHELES LARVAL habitats MALARIA Rudan Iran
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Larval habitats of mosquito fauna in Osogbo metropolis,Southwestern Nigeria 被引量:1
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作者 Monsuru Adebayo Adeleke Wasiu Olalekan Adebimpe +4 位作者 Abdulwasiu Oladele Hassan Sunday Olukayode Oladejo IsmailOlaoye Ganiyu Olatunji Olatunde Taiwo Adewole 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第9期673-677,共5页
Objective:To determine the larval habitats of mosquito fauna and possible impact of land use/land cover changes on the epidemiology of mosquito-bome diseases in Osogbo metropolis,Southwestern,Nigeria.Methods:All acces... Objective:To determine the larval habitats of mosquito fauna and possible impact of land use/land cover changes on the epidemiology of mosquito-bome diseases in Osogbo metropolis,Southwestern,Nigeria.Methods:All accessible larval habitats were surveyed between May and September,2011in Osogbo metropolis while Land Use/Land cover of the city was analyzed using 2 Lansat Multispectral Scanner satellite imagery of SPOT 1986 and T.ANDSAT TM 2009.Results:A total of six species namely,Aedes aegypti,Aedes albopictus,Aedes vittatus,Anopheles gambiae complex,Culex quinquefascialus and Erelmapodite chrysogaster were encountered during the study.The occurrence and contribution of disused tyres was significantly higher(P<0.05)than the other habitats encountered,while there were no significant differences in the contribution of gutters/run-offs.septic tanks/drums,ground pools/open drains and discarded containers lo the breeding of mosquitoes(P>0.05).The accessible land use/land covered of the study area between 1986 and 2009 showed that the wet land coverage and settlement area increased from 0.19 lo 9.09 hectare and 1.00 to 2.01 hectare respectively while the forest area decreased from 60.18 to 50.14 hectare.Conclusion:The contribution of the habitats coupled with the increasing rale of flooded environment which could provide ample breeding sites for mosquitoes call for sustained environmental sanitation and management in Osogbo metropolis. 展开更多
关键词 LARVAL habitats MOSQUITOES LAND use/land cover NIGERIA
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Bird species composition and diversity in habitats with different disturbance histories at Kilombero Wetland, Tanzania 被引量:1
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作者 Wilbard A. Ntongani Samora M. Andrew 《Open Journal of Ecology》 2013年第7期482-488,共7页
Wetland natural grasslands are important habitats for avian populations throughout the world. Unfortunately the increase of human population and rise in demand for settlements and agricultural land have degraded these... Wetland natural grasslands are important habitats for avian populations throughout the world. Unfortunately the increase of human population and rise in demand for settlements and agricultural land have degraded these habitats in many tropical wetlands. To effectively restore these natural grasslands and conserve avifaunal biodiversity, understanding of the relationships between habitat conditions and bird community structure are central. We used a combination of information from nearby villagers and field surveys to establish two important grassland habitats with low and high disturbance histories, and related the habitats to bird community structure. We surveyed a total of 119 sites in the two habitats to examine variation in the abundance, richness, diversity and composition of birds at Kilombero Wetland Tanzania. In total, 3049 individuals, 126 species, 88 genera and 45 families were recorded from Kilombero grasslands. Our results show that grasslands with low human disturbance had more number of bird species, genera, families and diversity (both ShannonWiener and Simpson) than the most disturbed grasslands atp 0.05) between low and highly disturbed grassland habitats suggesting that other factors including variety of foraging sites are important. This study confirms that the wetland grasslands of Kilombero are important for conservation of birds including rare and endemic species. It is recommended that anthropogenic disturbancesshould be minimized including control of fire, regulation of agricultural activities and population of cattle within the wetland system to restore and conserve biodiversity. 展开更多
关键词 Natural habitats Simplified Landscapes ANTHROPOGENIC DISTURBANCE Richness Biodiversity Kilombero Tanzania
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Flow Characteristic Variations on Groyne Types for Aquatic Habitats 被引量:1
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作者 Joongu Kang Hongkoo Yeo Sanghwa Jung 《Engineering(科研)》 2012年第11期809-815,共7页
The field formed by groyne has the function of aquatic habitats for the underwater biology. The characteristic of groyne field occurring around downstream of groyne depends on groyne type and shape. Thus to maximize t... The field formed by groyne has the function of aquatic habitats for the underwater biology. The characteristic of groyne field occurring around downstream of groyne depends on groyne type and shape. Thus to maximize the function of groyne, it needs to understand the flow characteristic around groyne. In this study, experiment model test was conducted in recirculation zone located in downstream of groyne. Groyne types for experiment are three: permeable, impermeable and inclined crest groyne. LSPIV (Large Scale Particle Image Velocimetry) is used to measure flow field around the groyne and it revealed flow characteristic in recirculation zone at each case. In order to estimate the aquatic habitats of groyne fields, critical swimming speed of major fleshwater fish in Korea was compared with the variation of velocity distribution in groyne fields. From the results, the rate of velocity decreases in groyne fields, V/Vapp were measured to be 0 to 0.5 and the results can be fundamental data which are used to estimate the aquatic habitable function of groyne. 展开更多
关键词 Groyne Recirculation Area AQUATIC habitats CRITICAL SWIMMING SPEED
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Environmental Consequences of Oil Spills on Marine Habitats and the Mitigating Measures—The Niger Delta Perspective 被引量:1
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作者 Etuk Etiese Akpan 《Journal of Geoscience and Environment Protection》 2022年第6期191-203,共13页
The Niger Delta region has witnessed environmental impacts arising from oil production activities. Soil fertility in these areas and the entire marine habitat was investigated based on the re-occurring spill incidents... The Niger Delta region has witnessed environmental impacts arising from oil production activities. Soil fertility in these areas and the entire marine habitat was investigated based on the re-occurring spill incidents in the area to establish the consequences of oil pollution on key performance indicators as well as the remedial actions for resuscitation. One of the bases of evaluation was on the fertility profile of the area impacted by oil spills as compared with the areas without oil spills influence. A suitable cost effective and environmentally friendly technique to handle the pollutions in the Niger Delta region can be found in systematic containment, recovery, clean up and restoration of the marine habitat to its initial capacity and status to be able to sustain life once again. 展开更多
关键词 Oil Spills Environmental Consequences Oil Pollution and Impact Marine habitats Niger Delta
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Cannibalism, among Other Solutions of Adaption, in Habitats Where Food Is Not Available for Salamandra infraimmaculata Larvae Diet in Breeding Places in Xeric Habitats 被引量:1
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作者 Gad Degani 《Open Journal of Animal Sciences》 2016年第1期31-41,共11页
The present study examines the inherent flexibility in the feeding responses of S. infraimmaculata larvae to various breeding places. In addition, the study examines the hypothesis that in dry conditions, the water br... The present study examines the inherent flexibility in the feeding responses of S. infraimmaculata larvae to various breeding places. In addition, the study examines the hypothesis that in dry conditions, the water breeding places are the limiting factor for the survival and completion of the life cycle of populations of S. infraimmaculata. In the breeding sites, the food for larvae is not available, and cannibalism is the specific adaptation for larvae to grow and complete metamorphosis. S. infraimmaculata larvae feed on various invertebrates in different habitats, and cannibalism involves the adaptation to breeding places where food is not available. The growth only by cannibalism as the only way to adapt to these habitats because no food is found in breeding places at the southern border of its distribution is described here for the first time, not only in salamanders but in other animals as well. 展开更多
关键词 CANNIBALISM habitats SALAMANDRA
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Nutrient resorption and its influencing factors of typical desert plants in different habitats on the northern margin of the Tarim Basin, China
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作者 ZHOU Chongpeng GONG Lu +1 位作者 WU Xue LUO Yan 《Journal of Arid Land》 SCIE CSCD 2023年第7期858-870,共13页
The resorption of nutrients from senescent leaves allows plants to conserve and recycle nutrients. To explore the adaptation strategies of desert plants to nutrient-limited environments, we selected four typical deser... The resorption of nutrients from senescent leaves allows plants to conserve and recycle nutrients. To explore the adaptation strategies of desert plants to nutrient-limited environments, we selected four typical desert plants(Populus euphratica Oliv., Tamarix ramosissima Ledeb., Glycyrrhiza inflata Batal., and Alhagi camelorum Fisch.) growing in the desert area of the northern margin of the Tarim Basin,China. The contents of nitrogen(N), phosphorus(P), potassium(K), calcium(Ca), magnesium(Mg), and Ferrum(Fe) in the leaves of these four typical desert plants and their resorption characteristics were analyzed. The relationship of nutrient resorption efficiency with leaf functional traits and soil physical-chemical properties in two different habitats(saline-alkali land and sandy land) was discussed.The results showed that the four plants resorbed most of the elements. Ca was enriched in the leaves of P.euphratica, G. inflate, and A. camelorum;Mg was enriched in the leaves of G. inflata;and Fe was enriched in the leaves of the four plants. The results of the redundancy analysis showed that leaf thickness, soil electrical conductivity, and soil P content were the major factors affecting the nutrient resorption efficiency of the four plants. Leaf thickness was negatively correlated with N resorption efficiency(NRE),P resorption efficiency, and Fe resorption efficiency;soil electrical conductivity was positively correlated with the resorption efficiency of most elements;and soil P content was negatively correlated with the resorption efficiency of most elements in the plant leaves. The results showed that soil physical-chemical properties and soil nutrient contents had an important impact on the nutrient resorption of plant leaves.The same species growing in different habitats also differed in their resorption of different elements. The soil environment of plants and the biological characteristics of plant leaves affected the resorption of nutrient elements in different plants. The purpose of this study is to provide small-scale data support for the protection of ecosystems in nutrient-deficient areas by studying leaf functional strategies and nutrient conservation mechanisms of several typical desert plants. 展开更多
关键词 nutrient resorption leaf functional traits soil physical-chemical properties resorption efficiency different habitats desert plants
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Determination and Analysis of Amino Acid Content in Maca from Different Habitats and Varieties
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作者 Yuting LI Ziyi LI +1 位作者 Lin JIANG Deli XIAO 《Medicinal Plant》 CAS 2022年第3期1-5,8,共6页
[Objectives]To determine and analyze amino acid content in Maca from different habitats and varieties.[Methods]Maca from two habitats and three colors were selected and a kind of turnip commonly used was to fake Maca.... [Objectives]To determine and analyze amino acid content in Maca from different habitats and varieties.[Methods]Maca from two habitats and three colors were selected and a kind of turnip commonly used was to fake Maca.After optimizing the hydrolysis conditions,100 mg Maca samples were hydrolyzed in the concentration of 6 mol/L hydrochloric acid at 110℃for 24 h.The content range of amino acids in each sample was detected by HPLC.[Results]The average total content of amino acids in Maca was 9.52 g/100 g.Yunnan yellow Maca contained 16 kinds of amino acids,including 7 kinds of human essential amino acids,accounting for 17.2%of the total amino acids while Yunnan purple Maca held 16 kinds of amino acids,counting 7 kinds of human essential amino acids,accounting for 16.5%of the total amino acids.The amino acid ratio coefficient method also showed that the two kinds of Maca had higher nutritional value than the others.15 kinds of amino acids were detected in Yunnan black Maca,including 6 kinds of essential amino acids,accounting for 9.60%of the total amino acids.Among amino acids in Yunnan Maca,the highest content was Arg.A total of 12 kinds of amino acids,together with 6 essential human amino acids,were determined in Peru black Maca,accounting for 11.6%of the total amino acids.In Peru black Maca the highest concentration of amino acid was Pro.It was noteworthy that the amino acid species were comprehensive in Maca,and high level of amino acids resulted in high nutritional value.Its specific amino acid composition ratio was obviously different from Turnip,the counterfeit goods to deceive customers.[Conclusions]The method of automatic amino acid analyzer is simple and accurate,and can be used for the identification and content determination of amino acids in Maca as amino acid is an essential nutrient in Maca. 展开更多
关键词 MACA habitats VARIETIES Amino acid content
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Lesser Kestrel Foraging Habitats in Special Protection Areas in Agro-ecosystems
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作者 Antonia Galanaki Theodoros Kominos Martin John Jones 《Journal of Agricultural Science and Technology(A)》 2017年第7期479-492,共14页
The European Union (EU) Wild Birds Directive recognises that the most serious threats to wild birds' conservation in Europe are habitat loss and degradation, and hence, habitats of threatened and migratory species ... The European Union (EU) Wild Birds Directive recognises that the most serious threats to wild birds' conservation in Europe are habitat loss and degradation, and hence, habitats of threatened and migratory species must be protected with the establishment of the network of the special protection areas (SPAs) for migratory and endangered bird species in the EU member states. The major European population of the lesser kestrel Falco naumanni, a migratory falcon listed in Annex I of the Birds Directive, occurs in low-input farming systems in the Mediterranean basin, including Greece. The aim of this study was to identify foraging habitats of lesser kestrels and relate them to the delimited SPAs in the agro-ecosystems of Greece, where the stronghold of the species population for Greece occurs. Foraging habitat preferences were assessed using Poisson regression models (PRMs). SPAs were examined on whether they can effectively protect foraging habitats for breeding lesser kestrels in the study area. Foraging lesser kestrel abundance was positively associated with grasslands and non-irrigated land (dry cereals), and negatively associated with irrigated land (wet cotton), scrubland and woodland. Electricity facilities were used as foraging perches by lesser kestrels. The current SPAs cover a small percentage of the species' foraging sites and cannot be considered coherent enough to support and protect the foraging habitats of lesser kestrels and other priority species in the agro-ecosystems of the study area. Proposals for effective conservation of low-input farming systems, supporting priority species, are also presented. 展开更多
关键词 Falco naumanni special protection areas (SPAs) Poisson regression models (PRMs) foraging habitats species conservation AGRO-ECOSYSTEMS Greece.
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Changes in Tree Frog (<i>Hyla savignyi</i>) Coloration in Unstable Habitats at the Southern Border of Its Distribution
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作者 Gad Degani 《Open Journal of Animal Sciences》 2022年第1期68-75,共8页
<span style="font-family:Verdana;">This study examined the relationship between tree frog</span> (<i><i><span style="font-family:Verdana;">Hyla</span></i>&... <span style="font-family:Verdana;">This study examined the relationship between tree frog</span> (<i><i><span style="font-family:Verdana;">Hyla</span></i><span> <i><span style="font-family:Verdana;">savignyi</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> coloring and its different seasonal habitats at the southern border of its distribution. The results show that tree frog color is affected by the dominant colors in its habitat, which vary seasonally, especially between winter and summer. Tree frog colors were various shades of green, white, brown, and black. No genetic marker was found to characterize the color. The ability of a small frog to infer its own time with the help of color changes occurring in the habitat on the southern border of its distribution, which are relatively broad, gives this species an advantage.</span> 展开更多
关键词 Tree Frog Hyla savignyi COLORS Genetic Marker Winter Summer habitats
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The Yellow Spot Pattern of Salamander (Salamandra infraimmaculata) in Various Habitats at the Southern Border of Its Distribution in Israel
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作者 Gad Degani Gad Ish Am +6 位作者 Amit Biran Ish Am Neria Yatom Amir Marshansky Sivan Margalit Eitan Nissim Hava Goldstein Niva Shaked 《Open Journal of Animal Sciences》 CAS 2023年第1期114-125,共12页
The present study describes the different color-pattern phenotypes of yellow spots on the black back of Salamandra infraimmaculata in various habitats at the southern border of its distribution in Israel. At Tel Dan, ... The present study describes the different color-pattern phenotypes of yellow spots on the black back of Salamandra infraimmaculata in various habitats at the southern border of its distribution in Israel. At Tel Dan, we photographed 454 salamanders in moist habitats where water flows year round;100 of these were sampled to measure the percentage of yellow and black color on the back, and the number of spots on the head. At Kibbutz Sasa, 201 salamanders were photographed, of which 62 were sampled for the measurements. In Kibbutz Yehiam, 200 salamanders were photographed, and 60 were sampled for the measurements. At all sites, about a third of the salamanders were photographed more than once. For all three populations, yellow spots on the salamander back were found in one row, two rows or scattered. For two indices (proportion of yellow/black and number of spots on the head), the Dan population (under wet, running water all year round conditions) differed from the two other populations of salamanders (under semi-arid mountain conditions). The number of yellow spots on the head of the salamanders in the three populations varied from 1 to 7. In all populations, 4 spots pattern was the most common. In the Dan population, there were significantly more salamanders with 1 to 3 spots on their head than in the Sasa or Yehiam populations. No difference was found in the number of head spots for Sasa vs. Yehiam salamanders. The percentage of yellow on the black back was significantly larger for the Dan salamanders vs. the two other populations. The main question examined was whether there is an effect of the habitat conditions in isolated populations on the spot pattern on the salamander back. The answer is positive and is supported by previous studies. 展开更多
关键词 Salamandra infraimmaculata Color-Pattern habitats SPOTS YELLOW
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