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Effect of Perched Water Tables on Aluminosilicate Stability and Soil Genesis 被引量:4
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作者 ZHANG MIN , GONG ZITONG and A. D. KARATHANASIS College of Resources and Environment, Shandong Agricultural University, Tai’an 271018 (China) Institute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 (China) College of Agriculture, U 《Pedosphere》 SCIE CAS CSCD 2000年第3期247-256,共10页
The mineral stability and solute activities of soil solution extracted from selected horizons of seven studied pedons of Alfisols in Kentucky, USA, and the relationship between distribution of iron-manganese concretio... The mineral stability and solute activities of soil solution extracted from selected horizons of seven studied pedons of Alfisols in Kentucky, USA, and the relationship between distribution of iron-manganese concretions and the restrictive layers were investigated. The results showed that the genesis and development of these soils and mineral weathering trends were strongly influenced by the depth of bedrock and the presence of perched water tables at lithic (limestone) interfaces due to the dissolution and buffering effect of limestone bedrock. The extractable Mg/Ca ratio as depth function and soil depth above bedrock could be used as indices of weathering and degree of soil development. Maximum iron-manganese concretion accumulation was found to occur in the horizon overlying clay horizon (>40% clay) with a sharp increase in clay content (>10%), which suggested that zones of Fe-Mn concretion accumulation in soils of the Inner Bluegrass Region appeared to be a sensitive genetic indicator of argillic horizons with restrictive permeability. 展开更多
关键词 iron-manganese concretion perched water table soil environment soil genesD
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Geoelectrical survey over perched aquifers in the northern part of Upper Sakarya River Basin,Türkiye
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作者 Can Ertekin Emin U Ulugergerli 《Journal of Groundwater Science and Engineering》 2022年第4期335-352,共18页
In this study,a groundwater exploration survey was conducted using the DC Resistivity(DCR)method in a hydrogeological setting containing a perched aquifer.DCR data were gathered and an electrical tomography section wa... In this study,a groundwater exploration survey was conducted using the DC Resistivity(DCR)method in a hydrogeological setting containing a perched aquifer.DCR data were gathered and an electrical tomography section was recovered using conventional four-electrode instruments with a Schlumberger array and a two-dimensional(2D)inversion scheme.The proposed scheme was tested over a synthetic threedimensional(3D)subsurface model before deploying it in a field situation.The proposed method indicated that gathering data with simple four-electrode instruments at stations along a line and 2D inversion of datasets at multiple stations can recover depth intervals of the studied aquifer in the hydrogeological setting even if it has a 3D structure.In this study,2D inversion of parallel profiles formed a pseudo-3D volume of the subsurface resistivity structures and mapped out multiple resistive(>25 ohm·m)bodies at shallow(between 50-100 m)and deep sections(>150 m).In general,the proposed method is convenient to encounter geological units that have limited vertical and spatial extensions in any direction and presents resistivity contrast from groundwater-bearing geologic materials. 展开更多
关键词 GROUNDWATER perched Aquifer DC Resistivity Inversion Sakarya River Türkiye
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晶粒度与合金强度关系 被引量:65
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作者 路君 曾小勤 丁文江 《轻金属》 CSCD 北大核心 2008年第8期59-64,共6页
研究了晶粒度与合金强度之间关系,通过各种材料的屈服应力、显微硬度等力学性能及其与构成晶粒度之间的关系,从理论上分析了规律产生的原因,为材料变形机制的研究及材料设计提供了科学依据。
关键词 屈服应力 晶粒尺寸 合金强度 Hall—Perch关系
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Ground- and Surface-Water Interactions of a Pumice Aquifer in a Headwaters Watershed: Round Meadow, Fremont-Winema National Forest, Oregon, USA 被引量:1
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作者 Jonathan M. Weatherford Michael L. Cummings 《Journal of Water Resource and Protection》 2016年第11期1010-1034,共25页
Plinian pumice fall from the Holocene eruption of Mount Mazama in the Cascade volcanic arc is an unconfined, perched aquifer in south-central Oregon. The pumice aquifer provides near-surface groundwater storage that m... Plinian pumice fall from the Holocene eruption of Mount Mazama in the Cascade volcanic arc is an unconfined, perched aquifer in south-central Oregon. The pumice aquifer provides near-surface groundwater storage that maintains biologically diverse wetland environments. Wetland environments reflect post-eruption disruption of the once uniform pumice blanket by fluvial and lacustrine processes operating within the template of the pre-eruption landscape. In the 8.6 km<sup>2</sup> Round Meadow watershed the pumice aquifer interacts with a seasonally flooded meadow, fen, springs, and perennial stream. The laterally uniform, isotropic pumice aquifer is disrupted by flat-bottomed ephemeral stream valleys that drain to the seasonally flooded meadow. Surface water levels in the seasonally flooded meadow are controlled by a knickpoint developed on bedrock. The underlying aquifer is confined by a layer of glass-rich diatomaceous silt grading upward to organic-rich silt. Here, the aquifer is comprised of remnants of the pumice deposit, lag sand, and reworked pumice. The water level in the confined aquifer is maintained by recharge from the unconfined pumice aquifer following flow pathways beneath ephemeral stream valleys. The fen is developed on a down-thrown block of welded tuff and pre-eruption diatomaceous silt. Water levels in the fen are sensitive to inter-annual variations in precipitation. Low discharge, low temperature (5.0&#176C to 6.5&#176C), and low conductivity (30 to 50 μS/cm) springs appear to be fracture controlled and rising through welded tuff. Spring discharge and seepage through pumice from the welded tuff support perennial flow in the creek that also carries discharge from the seasonally flooded meadow when water levels are high enough to cross the knickpoint. 展开更多
关键词 Pumice Aquifer perched Aquifer Oregon Mount Mazama
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Depletive Water Balance and High Vulnerability Due to Conflicts over Access and Rights
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作者 Jawad Hasan Shoqeir 《Journal of Water Resource and Protection》 2014年第11期1011-1016,共6页
Sustainable water supply problem becomes strategic when inelastic demand levels are overhauling maximum available supplies. The situation is more acute when the groundwater recharge area is heavily populated, consist ... Sustainable water supply problem becomes strategic when inelastic demand levels are overhauling maximum available supplies. The situation is more acute when the groundwater recharge area is heavily populated, consist of urban, industrial and agricultural areas and above all have typical karstic morphology and extensive regions of thin or null soil cover. During winter season the infiltrated water mixed with the wastewater leaking from poorly designed cesspits and wastewater overflow from the treatment plants of the adjacent settlements. Currently, most of the recharge area is disturbed due to the ongoing urban development in Beitar Elite and Tzur Hadassah in conjunction with the planned Security Fence (apartheid wall) threatens to extend over ~70% of the aquifer recharge area. Such massive destruction in a small watershed leads to considerable decrease in springs discharge and could completely dry-out the springs at the upper part of the valley. The aim of this research is to improve understanding of the hydrologic processes controlling water quantity and quality of springs discharging small (3/yr) basin in the mountain aquifer. 展开更多
关键词 perched Aquifers MOUNTAIN AQUIFER Surface RUNOFF URBAN Development Fragile Environment
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SERUM IMMUNOGLOBULIN OF THE MANDARIN FISH,SINIPERCA CHUATSI WITH DEVELOPMENT OF POLYCLONAL ANTIBODY 被引量:4
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作者 张永安 聂品 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第4期332-337,共6页
Serum immunoglobulin from the mandarin fish, or the so called Chinese perch, Siniperca chuatsi (Basilewsky), was successfully purified using affinity chromatography. Heavy and light chains were detected on electrophor... Serum immunoglobulin from the mandarin fish, or the so called Chinese perch, Siniperca chuatsi (Basilewsky), was successfully purified using affinity chromatography. Heavy and light chains were detected on electrophoresis gel, with molecular weights being estimated at 72 and 29 kDa, respectively. The tetrameric IgM of S. chuatsi was calculated to be 808 kDa. The rabbit polyclonal antisera against the purifed immunoglobulin were developed and tested by Western blot analysis. The antisera reacted strongly with the heavy chains of S. chuatsi immunoglobulin. Humoral immune responses of the mandarin fish can then be examined using the developed polyclonal antibody. 展开更多
关键词 IMMUNOGLOBULIN polyclonal antibody mandarin fish Chinese perch Siniperca chuatsi
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Comparison of Nutritional Quality in Fish Maw Product of Croaker Protonibea diacanthus and Perch Lates niloticus 被引量:8
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作者 WEN Jing ZENG Ling +1 位作者 Chen Ziming XU Youhou 《Journal of Ocean University of China》 SCIE CAS 2016年第4期726-730,共5页
Fish maw(the dried swimbladders of fish) is ranked in the list of the four sea treasures in Chinese cuisine. Fish maw is mainly produced from croaker, which is the most highly priced. However, some of the fish maw bei... Fish maw(the dried swimbladders of fish) is ranked in the list of the four sea treasures in Chinese cuisine. Fish maw is mainly produced from croaker, which is the most highly priced. However, some of the fish maw being sold as croaker maw are in fact not from croaker, but from the Nile perch Lates niloticus. The present work determined and compared the proximate composition, amino acid and fatty acid composition of croaker Protonibea diacanthus maw and perch L. niloticus maw. The results indicated that both maws were high protein sources and low in fat content. The dominant amino acids in both maws were glycine, proline, glutamic acid, alanine and arginine. These amino acids constituted 66.2% and 66.4% of the total amino acids in P. diacanthus and L. niloticus, respectively. The ratio of FAA: TAA(functional amino acids: total amino acids) in both maws were 0.69. This is a good explanation for why fish maws have been widely utilized as a traditional tonic and remedy in Asia. Except valine and histidine, all the essential amino acid contents in P. diacanthus were higher than in L. niloticus. Moreover, croaker P. diacanthus maw contained more AA and DHA than perch L. niloticus maw, showing a higher ratio of n-3 / n-6, which is more desirable. 展开更多
关键词 perch Lates proline proximate arginine histidine explanation remedy contained tonic
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Persistence of malachite green and leucomalachite green in perch (Lateolabrax japonicus) 被引量:1
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作者 谭志军 邢丽红 +4 位作者 郭萌萌 王洪艳 江艳华 李兆新 翟毓秀 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期647-655,共9页
The persistence of malachite green (MG), and its metabolite leucomalachite green (LMG), in fish tissues is still unclear, leading to many trade disputes. In this research, we established and evaluated an HPLC method t... The persistence of malachite green (MG), and its metabolite leucomalachite green (LMG), in fish tissues is still unclear, leading to many trade disputes. In this research, we established and evaluated an HPLC method that could detect MG and LMG simultaneously, and then investigated the persistence of these two toxins in the tissues of juvenile perch (Lateolabrax japonicus) post sub-chronic MG exposure at 1.0 mg/L. Exposure lasted for 2 h everyday and was repeated six times. The perch were then placed in MG-free seawater for 100 d to eliminate the toxins. Results show that MG accumulated in the tissues, including the gills, liver, muscle, blood and viscera, and then was metabolized rapidly to LMG. The concentrations of these two toxins increased significantly with the accumulation process. In general, the highest concentrations of MG and LMG in all tissue exceeded 1 000 μg/kg, except for MG in the muscle. The order of accumulation levels (highest to lowest) of MG was gill>blood>liver>viscera>muscle, while that of LMG was liver>blood>gill>viscera>muscle. High levels of MG or LMG could persist for several hours but decreased rapidly during the elimination process. The concentration of LMG was much higher than that of MG during the experiment, especially in the gill, liver and blood. Therefore, the three tissues play important roles in toxin accumulation, biotransformation, and elimination. Although the MG and LMG concentrations in muscle were much lower than in other tissues, the content still exceeded the European minimum required performance limit (MRPL), even after 2 400 h (100 d) of elimination. This demonstrates that it is extremely difficult to eliminate MG and LMG from tissues of perch, and therefore use of these toxins is of concern to public health. 展开更多
关键词 PERSISTENCE RESIDUES malachite green leucomalachite green PERCH
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Shape reconstructions and morphing kinematics of an eagle during perching manoeuvres 被引量:1
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作者 Di Tang Dawei Liu +3 位作者 Hai Zhu Xipeng Huang Zhongyong Fan Mingxia Lei 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第2期327-336,共10页
The key to high manoeuvre ability in bird flight lies in the combined morphing of wings and tail.The perching of a wild Haliaeetus Albicilla without running or wing flapping is recorded and investigated using a high-s... The key to high manoeuvre ability in bird flight lies in the combined morphing of wings and tail.The perching of a wild Haliaeetus Albicilla without running or wing flapping is recorded and investigated using a high-speed digital video.A shape reconstruction method is proposed to describe wing contours and tail contours during perching.The avian airfoil geometries of the Aquila Chrysaetos are extracted from noncontact surface measurements using a ROMBER 3D laser scanner.The wing planform,chord distribution and twist distribution are fitted in convenient analytical expressions to obtain a 3D wing geometry.A three-jointed arm model is proposed to associate with the 3D wing geometry,while a one-joint arm model is proposed to describe the kinematics of tail.Therefore,a 3D bird model is established.The perching sequences of the wild eagle are recaptured and regenerated with the proposed 3D bird model.A quasi-steady aerodynamic model is applied in the aerodynamic predictions,a four-step Adams-Bashforth method is used to calculate the ordinary differential equations,thus a BFGS based optimization method is established to predict the perching motions. 展开更多
关键词 large BIRD of PREY shape reconstruction MORPHING KINEMATIC PERCHING
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CHARACTERIZATION OF LACTATE DEHYDROGENASE ISOZYME PATTERN AND MORPHOLOGY OF THREE MARINE FISH CELL LINES 被引量:1
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作者 郭华荣 张士璀 +2 位作者 李红岩 童裳亮 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期226-231,共6页
Three continuous marine fish cell lines of FG (i.e., Flounder Gill) from flounder ( Paralichthys olivaceus) gill, SPH (i.e., Sea Perch Heart) from sea perch ( Lateolabrax japonicus ) heart and RSBF (i.e., Red Sea... Three continuous marine fish cell lines of FG (i.e., Flounder Gill) from flounder ( Paralichthys olivaceus) gill, SPH (i.e., Sea Perch Heart) from sea perch ( Lateolabrax japonicus ) heart and RSBF (i.e., Red Sea Bream Fin) from red sea bream ( Pagrosomus major ) fin, were characterized by lactate dehydrogenase (LDH) isozyme and morphological analysis. The LDH isozyme patterns of these three cell lines and their corresponding tissues of origin were investigated and compared. The results showed: (1) No difference was found in the LDH isozyme patterns of FG and flounder gill tissue. However, the LDH isozyme patterns of SPH and RSBF were significantly different from their corresponding tissues of origin; (2) LDH isozyme patterns of FG, SPH and RSBF were markedly different from each other and could serve as genetic markers for species identification and detection of cross contamination. Morphological change analysis of these three cell lines in comparison to their original tissues indicated that FG cells still appeared epithelioid without morphological transformation. However, morphological changes were found in SPH and RSBF compared to their original tissues. Therefore, the cellular morphology was still plastic in the relatively stable culture conditions, and it was possible that change of LDH patterns was related to morphological changes of fish cells in vitro . 展开更多
关键词 cell line lactate dehydrogenase cellular morphology FLOUNDER sea perch red sea bream
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Molecular cloning and expression analysis of interleukin - 1β from Japanese sea perch(Lateolabrax japonicus ) 被引量:1
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作者 QIU Lihua SONG Linsheng +2 位作者 WU Longtao CAI Zhonghua JIANG Shigui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第1期127-136,共10页
The technology of homology cloning and anchored PCR was used to clone the IL-1β gene from the Japanese sea perch (Lateolabrax iaponicus). The full-length cDNA of sea perch IL-1β was 1 310 bp, including a 5' untra... The technology of homology cloning and anchored PCR was used to clone the IL-1β gene from the Japanese sea perch (Lateolabrax iaponicus). The full-length cDNA of sea perch IL-1β was 1 310 bp, including a 5' untranslated regiop (UTR) of 136 bp, a 3' UTR ot 430 bp, and an ORF of 774 bp encoding a polypeptide of 258 amino acids with an estimated molecular mass of 29.31 kDa. The searches for nucleotides and protein sequence similarities with the BLAST analysis indicated that the deduced amino acid sequence of sea perch IL-1β was homological to the IL-1β in other fish species and even the mammalian. Conserved signature sequences of the IL-1β gene family were found in the sea perch IL-1β deduced amino acid sequence. Temporal expressions of the IL-1β gene in LPS or iridovirus challenged group and in control group were measured by the semi-quantitative RT-PCR. The mRNA transcripts of IL-1β could be detected in head-kidney, spleen, liver, gill and heart of the healthy individuals, and the expression level of IL-1β in head-kidney, spleen and gill was higher than that in liver and heart, but it was hard to be detected in the brain. After being stimulated by the LPS or iridovirus, the IL-1β expression in most of examined tissues was up-regulated, and also could be detected in the brain. These results indicated that the expression of sea perch IL-1β was constitutive and could be up-regulated by immune effector stimulation. Therefore the sea perch IL-1β could play a critical role in the host-pathogen interaction. 展开更多
关键词 Japanese sea perch INTERLEUKIN-1Β gene cloning CDNA mRNA expression
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Habitat use and space preferences of Eurasian Bullfinches(Pyrrhula pyrrhula)in northwestern Iberia throughout the year 被引量:1
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作者 Angel Hernández 《Avian Research》 CSCD 2021年第1期37-51,共15页
Background:For all vertebrates in general,a concerted effort to move beyond single season research is vital to improve our understanding of species ecology.Knowledge of habitat use and selection by Eurasian Bullfinche... Background:For all vertebrates in general,a concerted effort to move beyond single season research is vital to improve our understanding of species ecology.Knowledge of habitat use and selection by Eurasian Bullfinches(Pyrrhula pyrrhula)is limited with regard to the non-breeding season.To date,research on the habitat of the Iberian subspecies iberiae consists of very general descriptions.In relation to space use,only broad features are available for the entire distribution range of Eurasian Bullfinches,including Iberia.Methods:In this study,seasonal preferences regarding habitat and space in a population of Eurasian Bullfinches are examined for the first time in the Iberian Peninsula,through direct observation during a six-year period.The essential habitat components,substrate selection and perch height were assessed.Results:Hedgerows were the key essential habitat component for bullfinches during all seasons.Nevertheless,small poplar plantations became increasingly important from winter to summer-autumn.Bullfinches perched mostly in shrubs/trees throughout the year,but there were significant seasonal changes in substrate use,ground and herbs being of considerable importance during spring-summer.Throughout the year,over half of the records corresponded to feeding,reaching almost 90%in winter.Generally,bullfinches perched noticeably lower while feeding.Male bullfinches perched markedly higher than females,notably singing males in spring-summer.Juveniles perched at a height not much lower than that of males.In all seasons,males tended to feed at greater heights than females.Bullfinches of different ages and sexes were seen bathing in all seasons except winter.Conclusions:Hedgerow habitat in general appeared to be valuable for bullfinches throughout the year.In summer and autumn,they selected sites with an abundance of food and shade,as well as shelter,a much-needed requirement for fledglings and moulting individuals.There was usually a close link between the most used and most consumed plant species in each season.Males appeared to assume a more important role in vigilance,and often they accompanied dependent young in June and July.Bullfinch conservation strategies should consider seasonal demand for habitat and space. 展开更多
关键词 Habitat use Perch height Pyrrhula pyrrhula iberiae Seasonal variation Substrate selection Water bathing
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Pond Substrate Type Affects Yellow Perch Fingerling Size at Harvest 被引量:1
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作者 Matthew J. Ward 《Open Journal of Animal Sciences》 2021年第1期31-36,共6页
Fish size and harvest density generally exhibit a negative relationship in pond culture, but the influence that pond substrate type can have on this relationship is not well understood. To evaluate the influence of po... Fish size and harvest density generally exhibit a negative relationship in pond culture, but the influence that pond substrate type can have on this relationship is not well understood. To evaluate the influence of pond substrate type on yellow perch (<i></span><i><span style="font-family:Verdana;">Perca flavescens</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;">), harvest density (number/hectare) was linearly regressed against individual fingerling size (grams) for lined (n = 48) and earthen (n = 40) substrate ponds that were treated similarly in terms of organic fertilizer use and the number of days in the pond over 12 culture seasons at Blue Dog Lake State Hatchery, South Dakota, USA. Harvest density explained 45 and 39% of the variation in yellow perch size in lined and earthen-substrate ponds (all <i></span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;"> < 0.01). Comparison of regression lines indicated that fingerling size decreased as harvest density increased at a similar rate in both pond types (slope comparison, <i></span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;"> = 0.62);however, fingerling size was significantly larger in lined ponds regardless of density that varied from near 0 to 700,000 per hectare (y-intercept comparison, <i></span><i><span style="font-family:Verdana;">P</span></i><span style="font-family:Verdana;"></i></span><span style="font-family:Verdana;"> < 0.01). At the same harvest density, lined ponds will tend to produce larger yellow perch fingerlings compared to earthen ponds when similar organic fertilizers are used. 展开更多
关键词 Yellow Perch Pond Culture Pond-Substrate Type
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Demographic and behavioral responses of the White-winged Dove to human disturbances during winter in northwestern Mexico
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作者 Ruben Ortega-Alvarez Jovani Le on-Aguilar +1 位作者 Antonio Isain Contreras-Rodríguez Gustavo Casta neda de los Santos 《Avian Research》 SCIE CSCD 2022年第4期437-444,共8页
The simultaneous study of demography and behavior might provide a more comprehensive understanding about animal responses to anthropogenic disturbances.The White-winged Dove(Zenaida asiatica)is a frequent dweller of u... The simultaneous study of demography and behavior might provide a more comprehensive understanding about animal responses to anthropogenic disturbances.The White-winged Dove(Zenaida asiatica)is a frequent dweller of urban and agricultural habitats in North America,Central America,and the Caribbean.Still,research on the species is heavily biased to the USA.We analyzed the response of the species to human disturbances during winter across an urban-agricultural landscape in northwestern Mexico through a demographic and behavioral approach.We modeled the effect of disturbance types(pedestrians,cars,pavement and building cover)on the density of the species.Also,we investigated if surveillance behavior varied across the landscape by estimating and comparing perching proportion among land uses(urban grey areas,urban green areas,cropfields,shrublands).We did not detect the species within cropfields,possibly because food resources were not available for the dove during winter in this land use.Pavement cover limited species’density,as it might reduce the surface of the preferred feeding substrates of the dove.Pedestrians and building cover increased the density of the species,as they might provide food and shelter for the dove,respectively.Surveillance behavior peaked in urban grey areas,whereas it dropped in urban green areas.Differences on threat levels,threat type,and protective cover among land uses might in-fluence such behavioral pattern.Our approach contributes to the knowledge of the species and demonstrates that both demographic and behavioral cues provide complementary evidence for analyzing the impact of human disturbances on animals. 展开更多
关键词 AGRICULTURE Density PERCH Sinaloa URBANIZATION Zenaida asiatica
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Perch Associated Expression of Phenotypic Plasticity in Limb Development and Sprint Speed in Agamid Lizard Calotes versicolor: A Laboratory Study
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作者 Veena H.F.AMMANNA Srinivas K.SAIDAPUR Bhagyashri A.SHANBHAG 《Asian Herpetological Research》 SCIE CSCD 2018年第3期175-181,共7页
New born hatchlings of Calotes versicolor were reared in terrarium having narrow or wide perches for a period of 4-month and their snout vent length(SVL), tail, fore and hindlimb lengths were measured at monthly int... New born hatchlings of Calotes versicolor were reared in terrarium having narrow or wide perches for a period of 4-month and their snout vent length(SVL), tail, fore and hindlimb lengths were measured at monthly intervals. Limb postures(closer to the body or spread away from the body) were also recorded. The sprint speed was recorded in two and four-month old lizards on a 1 m long race track providing 45° or 60° slope. In both the groups, SVL and tail lengths were comparable but the limb lengths and their growth rates were significantly greater in lizards of wider perch group. The lizards reared with narrow perches positioned their limbs closer to the body; while those reared on wider perches spread their limbs away from their body. Further, the latter exhibited significantly higher sprint speed regardless of the slope of the race track over those of narrow perch group. Sprint speeds of lizards in both groups were correlated with the limb sizes. The study showed that the lizards reared on narrow or wide perches exhibited divergent adaptive responses(phenotypic plasticity) by developing longer or shorter limbs and corresponding changes in their sprint speeds. These findings support the idea that availability of perch structure during early development evokes adaptive plasticity in the limb development and associated locomotory performance in arboreal lizards like C. versicolor. 展开更多
关键词 behavior Calotes HATCHLINGS LIMB LIZARD PERCH PLASTICITY sprint speed
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Spatio-temporal patterns of the Red-footed Falcon's hunting behavior during the nestling period suggest ad hoc conservation policies
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作者 Marco Gustin Alessandro Ferrarini 《Avian Research》 CSCD 2021年第1期118-123,共6页
The Red-footed Falcon(Falco vespertinus)is a species of high international conservation interest.We analyzed its hunting behavior at the two largest colonies in Italy during the nestling period.Using accurate data-log... The Red-footed Falcon(Falco vespertinus)is a species of high international conservation interest.We analyzed its hunting behavior at the two largest colonies in Italy during the nestling period.Using accurate data-loggers,we tracked three adult Red-footed Falcons in June and July,2019 and collected 4703 GPS points.We detected clear patterns of hovering and perching activity(HPA)in both time and space.HPA occupied one-third of the Red-footed Falcons’day,and showed two peaks just after sunrise(between 35 and 40%of the monitoring time)and just before sunset(50‒60%)in both June and July,and minimum(20‒30%)at night and during the hottest time interval(10:00 a.m.‒4:00 p.m.).Almost 40%of HPA occurred within 50 m from nests.Our findings,although preliminary,have important implications for the conservation of these two colonies that are located within two Natura 2000 sites.The detected spatio-temporal patterns of Red-footed Falcons’hunting behavior suggests the creation of two nested protection belts:the inner one is a narrow belt(up to 50 m from the two rows of trees that host the two colonies)with integral conservation,and hopefully increase the alfalfa crops and fallow land,and the outer belt(50 m‒2 km)with optimized agricultural activities. 展开更多
关键词 BIOTELEMETRY Falco vespertinus Hovering ITALY Natura 2000 site PERCHING
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Avian-power line interactions in the Gobi Desert of Mongolia:are mitigation actions effective?
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作者 Adrian Orihuela-Torres Juan MPérez-García +3 位作者 Zebensui Morales-Reyes Lara Naves-Alegre JoséASánchez-Zapata Esther Sebastián-González 《Avian Research》 CSCD 2021年第3期382-390,共9页
Background:Electrocution and collisions on power lines are among the leading causes of non-natural mortality for birds.Power lines are exponentially increasing,particularly in developing countries,but mitigation strat... Background:Electrocution and collisions on power lines are among the leading causes of non-natural mortality for birds.Power lines are exponentially increasing,particularly in developing countries,but mitigation strategies to prevent bird mortality are questionable.Mongolia combines a recently increased power line network,an abundant raptor population,a dangerous crossarm configuration and a habitat with no natural perches,producing many bird-power line interactions.Our aim is to assess the bird mortality caused by power lines in the Gobi Desert of Mongolia,to determine the factors increasing the risk of bird electrocution,and to evaluate the effectiveness of used retrofitting measures.Methods:In July 2019 we covered 132.9 km of 15 kV power lines checking 1092 poles.We also conducted bird tran-sects to record raptor and corvid richness and abundance,to assess species vulnerability to electrocution.Results:We recorded 76 electrocuted birds of 7 species.Electrocution rate was 6.96 birds/100 poles.The most affected species were Common Raven(Corvus corax)and Upland Buzzard(Buteo hemilasius),highlighting the electro-cution of 5 endangered Saker Falcons(Falco cherrug).By contrast,we only recorded 8 individuals of 5 species collid-ing with wires,the most affected being Pallas’s Sandgrouse(Syrrhaptes paradoxus).About 76.1%of sampled poles had some mitigation measure.Of these,96.6%were brush perch deflectors and 3.4%rotating-mirrors perch deter-rents.We found differences in electrocution rates among crossarm configurations,with the strain insulator with one jumper being the most lethal.Additionally,we found no correlation between bird abundance and electrocution rates,suggesting that some species are more sensitive to electrocution.Although no differences in total bird electrocu-tion rates were detected between poles with and without perch deterrents,when bird size is considered,deterrents reduced the mortality rate of small birds,while they were ineffective for medium-sized birds.Conclusions:Despite the widespread use of perch deterrents in the Mongolian power line network,there is still an alarming electrocution rate.This strategy is ineffective and some mechanisms,such as brush perch deflectors,may increase the electrocution rate for some medium-sized birds.Finally,we propose strategies to minimize the avian electrocution rate in the Gobi Desert. 展开更多
关键词 Collision Crossarm configuration ELECTROCUTION Electric infrastructures Perch deterrent Power line network RAPTOR
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Ecological Devastation in Lake Victoria: Part A: Thermal Structure and Anoxia
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作者 Moshe Gophen 《Open Journal of Ecology》 2015年第7期287-298,共12页
Lake Victoria is the second (excl. Caspian Sea) largest lake in the world by surface area and 7th by Volume. The lake and catchment territories are shared between three countries, Kenya, Uganda and Tanzania. A researc... Lake Victoria is the second (excl. Caspian Sea) largest lake in the world by surface area and 7th by Volume. The lake and catchment territories are shared between three countries, Kenya, Uganda and Tanzania. A research was carried out during 1990-1992 exploring the changes of the thermo-chemical structure occurred after the invasion of Nile Perch. Results of changes of physico-chemical (Temperature, DO and pH) conditions are summarized in this paper. The anoxic conditions by space and time were enhanced. Enhancement of pollutant supply from anthropogenic developments of terrestrial sources and atmospheric dust deposition accompanied by the deleterious effects of the Nile Perch invasion caused enhancement of anoxia in the lake in space and time. The combination of bottom-up nutrient supply and strong mixing conditions, expressed as low RTR values accelerate phytoplankton growth rate and production. The surplus of organic matter originated from algal biomass, enhanced anoxia. 展开更多
关键词 Lake VICTORIA Kenya NILE PERCH ANOXIA Thermal Stability
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Ecological Devastation in Lake Victoria: Part B: Plankton and Fish Communities
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作者 Moshe Gophen 《Open Journal of Ecology》 2015年第7期315-325,共11页
A few specimens of the exotic fish, Nile Perch, (Lates niloticus, Linnaeus 1758) were transferred into Lake Victoria in early 1950’s. In early 1980’s this fish occupied the Lake Victoria ecosystem eliminating the lo... A few specimens of the exotic fish, Nile Perch, (Lates niloticus, Linnaeus 1758) were transferred into Lake Victoria in early 1950’s. In early 1980’s this fish occupied the Lake Victoria ecosystem eliminating the local endemic Haplochromines (app. 400 species). As a result of this change, together with intensification of pollution constrains from the catchment and dust deposition the ecology of Victoria’s ecosystem was modified: cyanobacteria replaced diatoms, anoxia enhanced, secchi depth became shallower, euphotic zone became thinner, fishery enhanced fully comprised of Nile Perch and Rastrineobola. The ecological significances are discussed and future propositions are presented. 展开更多
关键词 LAKE VICTORIA NILE PERCH ECOLOGICAL Changes Fish PLANKTON
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Influence of Amino Acid Supplementations in Juvenile Yellow Perch Fed Plant Protein Combinations
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作者 Aaron J. Von Eschen Michael L. Brown Kurt Rosentrater 《Open Journal of Animal Sciences》 2019年第2期183-195,共13页
Distillers dried grains with solubles (DDGS) in combination with soy protein concentrate (SPC) with and without an essential amino acid (EAA) complex were assessed as protein alternatives in juvenile Yellow Perch Perc... Distillers dried grains with solubles (DDGS) in combination with soy protein concentrate (SPC) with and without an essential amino acid (EAA) complex were assessed as protein alternatives in juvenile Yellow Perch Perca flavescens diets. Diets contained 5% FM, 40% SPC, and 20% or 40% DDGS each with or without EAA. No mortalities or health assessment differences were observed during the trial and all fish readily accepted the experimental diets. Diets supplemented with EAA produced greater weight gain, improved feed conversion, and apparent protein digestibility. Performance was consistently improved for fish fed diets containing amino acid supplements. Based on these results, Yellow Perch are able to utilize high levels of the plant proteins, accompanied with EAAs, as a FM replacer. 展开更多
关键词 Yellow PERCH Fish Nutrition Distillers DRIED Grains with Solubles SOY Protein CONCENTRATE Amino Acids
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