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一种基于后缀排序快速实现Burrows-Wheeler变换的方法 被引量:3
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作者 李冰 龙冰洁 刘勇 《电子与信息学报》 EI CSCD 北大核心 2015年第2期504-508,共5页
近年来,Bzip2压缩算法凭借其在压缩率方面的优势,得到了越来越多的应用,Bzip2的核心算法是Burrows-Wheeler变换(BWT),BWT能有效的将数据中相同的字符聚集到一起,为进一步压缩创造条件。在硬件实现BWT时,常用的基于后缀排序的算法能有效... 近年来,Bzip2压缩算法凭借其在压缩率方面的优势,得到了越来越多的应用,Bzip2的核心算法是Burrows-Wheeler变换(BWT),BWT能有效的将数据中相同的字符聚集到一起,为进一步压缩创造条件。在硬件实现BWT时,常用的基于后缀排序的算法能有效克服BWT消耗存储资源大的问题,该文对基于后缀排序实现BWT的方法进行了详细分析,并且在此基础上提出了一种快速实现BWT的方法后缀段算法。仿真结果表明后缀段算法在处理速度上比传统的基于后缀排序的算法有很大的提高。 展开更多
关键词 信号处理 数据压缩 Bzip2 burrows-Wheeler变换 后缀排序
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A Review of the Engineering Role of Burrowing Animals: Implication of Chinese Pangolin as an Ecosystem Engineer
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作者 Song Sun Hongliang Dou +9 位作者 Shichao Wei Yani Fang Zexu Long Jiao Wang Fuyu An Jinqian Xu Tingting Xue Huangjie Qiu Yan Hua Guangshun Jiang 《Journal of Zoological Research》 2021年第3期1-20,共20页
Ecosystem engineers are organisms that alter the distribution of resources in the environment by creating,modifying,maintaining and/or destroying the habitat.They can affect the structure and function of the whole eco... Ecosystem engineers are organisms that alter the distribution of resources in the environment by creating,modifying,maintaining and/or destroying the habitat.They can affect the structure and function of the whole ecosystem furthermore.Burrowing engineers are an important group in ecosystem engineers as they play a critical role in soil translocation and habitat creation in various types of environment.However,few researchers have systematically summarized and analyzed the studies of burrowing engineers.We reviewing the existing ecological studies of burrowing engineer about their interaction with habitat through five directions:(1)soil turnover;(2)changing soil physicochemical properties;(3)changing plant community structure;(4)providing limited resources for commensal animals;and/or(5)affecting animal communities.The Chinese pangolin(Manis pentadactyla)is a typical example of burrowing mammals,in part(5),we focus on the interspecific relationships among burrow commensal species of Chinese pangolin.The engineering effects vary with environmental gradient,literature indicates that burrowing engineer play a stronger role in habitat transformation in the tropical and subtropical areas.The most common experiment method is comparative measurements(include different spatial and temporal scale),manipulative experiment is relatively few.We found that most of the engineering effects had positive feedback to the local ecosystem,increased plant abundance and resilience,increased biodiversity and consequently improved ecosystem functioning.With the global background of dramatic climate change and biodiversity loss in recent decades,we recommend future studies should improving knowledge of long-term engineering effects on population scale and landscape scale,exploring ecological cascades through trophic and engineering pathways,to better understand the attribute of the burrowing behavior of engineers to restore ecosystems and habitat creation.The review is presented as an aid to systematically expound the engineering effect of burrowing animals in the ecosystem,and provided new ideas and advice for planning and implementing conservation management. 展开更多
关键词 burrowing engineer burrow commensal species Chinese pangolin Ecosystem engineer Habitat modification Biodiversity
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Burrow Characteristics and Microhabitat Use of the Turpan Wonder Gecko Teratoscincus roborowskii (Squamata, Gekkonidae) 被引量:3
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作者 Yucheng SONG Yang LIU +2 位作者 Yingying LIN Tao LIANG Lei SHI 《Asian Herpetological Research》 SCIE CSCD 2017年第1期61-69,共9页
Burrow structural charactersitcs and microhabitat use of the Turpan wonder gecko Teratoscincus roborowskii (Gekkonidae) were studied between April and September of 2013 in the Turpan Eremophytes Botanic Garden, in t... Burrow structural charactersitcs and microhabitat use of the Turpan wonder gecko Teratoscincus roborowskii (Gekkonidae) were studied between April and September of 2013 in the Turpan Eremophytes Botanic Garden, in the Turpan Depression of Western China. Burrow depth, entrance orientation, entrance height and width were observed. We assessed microhabitat selection and noted differences in microhabitat use among males, females, and juveniles. The magnitude of selection was measured using Jacobs' index of selectivity. Entrance height and width of the burrows of adults were significantly larger than those of juveniles, but the difference in burrow depth was not significant. The directional orientation of the burrow entrance showed a preference for the north-northeast and south-southeast, which were likely influenced by local prevailing winds and sunlight. Both the adult and juvenile geckos prefer to construct their burrows in sandy soil within a layer of loose soil whose thickness is greater than 30 cm. A majority of the burrows were located within 20 m of the nearest plant. Nearly half (48%) of the entrances of juveniles were located within 5 m of the nearest vegetation, significantly different from those of the adults. Results showed that the Turpan wonder gecko did not utilize microhabitats according to their availability, but rather that it preferred rnicrohabitats which contained dead wood or the caper bush. Our results suggested that burrow characteristics and microhabitat selection were important factors in T. roborowskii adaptation to harsh and arid desert habitats. 展开更多
关键词 arid desert habitat burrow depth entrance height entrance orientation entrance width microhabitatselection retreat site
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Large Tetrapod Burrows from the Permian Naobaogou Formation of the Daqingshan Area, Nei Mongol, China 被引量:2
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作者 LIU Jun LI Lu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第6期1501-1507,共7页
Two new tetrapod burrow casts from the Naobaogou Formation (Middle or Late Permian) of Nei Mongol,China are described.It marks the first pre-Cenozoic tetrapod burrow from China,and one of the earliest records of tet... Two new tetrapod burrow casts from the Naobaogou Formation (Middle or Late Permian) of Nei Mongol,China are described.It marks the first pre-Cenozoic tetrapod burrow from China,and one of the earliest records of tetrapod burrows.Comparison to other Permian and Triassic burrows suggests that these burrows were created by tetrapod slightly smaller than Lystrosaurus.Deduced from the morphology and sizes of two burrows and known tetrapods of the Naobaogou Formation,the burrow should be the production of a therapsid,most likely a dicynodon.These burrows indicate a seasonal climate and this area was semiarid or arid during that time. 展开更多
关键词 burrow Naobaogou Formation dicynodon therocephalian
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Effect of mangrove restoration on crab burrow density in Luoyangjiang Estuary,China 被引量:2
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作者 Wei Li Lijuan Cui +4 位作者 Manyin Zhang Yifei Wang Yaqiong Zhang Yinru Lei Xinsheng Zhao 《Forest Ecosystems》 SCIE CSCD 2015年第4期263-271,共9页
Background: Mangrove restoration seeks to restore or rebuild degraded mangrove systems. The methods of mangrove restoration include ecological projects and restoration-oriented technologies, the latter of which are d... Background: Mangrove restoration seeks to restore or rebuild degraded mangrove systems. The methods of mangrove restoration include ecological projects and restoration-oriented technologies, the latter of which are designed to restore the structure, processes as well as related physical, chemical and biological characteristics of wetlands and to ensure the provision of ecosystem services. As important components of mangrove ecosystem, benthic organisms and crabs play a key role in nutrient cycling. In addition, mangrove restoration, such as vegetation restoration measures, can lead to changes in the benthic faunal communities. This study investigates whether the presence of different mangrove species, age and canopy cover of mangrove communities affect the density of crab burrows. Methods: The Luoyangjiang Estuary, in the southeast of Fujian Province, was selected as our research area. A survey, covering 14 sites, was conducted to investigate the impacts of mangrove restoration on the density of crab burrows in four rehabilitated forests with different stand ages and canopy. Results: It was found that differences in vegetation types had a large impact on crab density and that the density of crab burrows was lower on exposed beaches (non-mangrove) than under mature Kondelio condel, Aegiceros corniculatum and Avicennio morina communities. In general, the amount of leaf litter and debris on mangrove mudfiats was greater than on the beaches as food sources for crabs. Two-factor analysis of variance (ANOVA) shows that changes in mangrove species and age since restoration had different effects on crab burrow density. The effect of canopy cover was highly significant on crab burrow density. Conclusions: The results suggest that in the process of mangrove restoration the combined effects of mangrove stand age, canopy cover and other factors should be taken into account. This study further supports the findings of the future scientific research and practice on mangrove restoration and management measures. 展开更多
关键词 CANOPY Crab burrow density MANGROVE RESTORATION
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基于扩展Burrows-Wheeler算法重构禽流感病毒的进化树
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作者 夏阳 白凤兰 刘立伟 《大连交通大学学报》 CAS 2014年第5期116-120,共5页
基于核苷酸的物理化学性质,利用扩展Burrows-Wheeler算法和Burrows-Wheeler相似性分布,对80种H5NI病毒的DNA序列的HA片段进行相似性比较,同时构建序列进化树,得到较好的结果.通过分析禽流感病毒之间的相似度关系,可为研究禽流感区域蔓... 基于核苷酸的物理化学性质,利用扩展Burrows-Wheeler算法和Burrows-Wheeler相似性分布,对80种H5NI病毒的DNA序列的HA片段进行相似性比较,同时构建序列进化树,得到较好的结果.通过分析禽流感病毒之间的相似度关系,可为研究禽流感区域蔓延的特点提供一定的理论依据. 展开更多
关键词 扩展burrows-Wheeler算法 禽流感病毒 进化树
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The hypoxia adaptation of small mammals to plateau and underground burrow conditions 被引量:3
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作者 Mengke Li Dan Pan +4 位作者 Hong Sun Lei Zhang Han Cheng Tian Shao Zhenlong Wang 《Animal Models and Experimental Medicine》 CSCD 2021年第4期319-328,共10页
Oxygen is one of the important substances for the survival of most life systems on the earth,and plateau and underground burrow systems are two typical hypoxic environments.Small mammals living in hypoxic environments... Oxygen is one of the important substances for the survival of most life systems on the earth,and plateau and underground burrow systems are two typical hypoxic environments.Small mammals living in hypoxic environments have evolved different adaptation strategies,which include increased oxygen delivery,metabolic regulation of physiological responses and other physiological responses that change tissue oxygen utilization.Multiomics predictions have also shown that these animals have evolved different adaptations to extreme environments.In particular,vascular endothelial growth factor(VEGF)and erythropoietin(EPO),which have specific functions in the control of O_(2) delivery,have evolved adaptively in small mammals in hypoxic environments.Naked mole-rats and blind mole-rats are typical hypoxic model animals as they have some resistance to cancer.This review primarily summarizes the main living environment of hypoxia tolerant small mammals,as well as the changes of phenotype,physiochemical characteristics and gene expression mode of their long-term living in hypoxia environment. 展开更多
关键词 hypoxia adaptation multi-omics PLATEAU small mammals underground burrow systems
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The Habitats, Burrowing Behavior, Physiology Adaptation and Life Cycle of Spadefoot Toads (<i>Pelobates syriacus, Boettge</i>r, 1869) at the Southern Limit of Its Distribution in Israel 被引量:1
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作者 Gad Degani 《Open Journal of Animal Sciences》 2015年第3期249-257,共9页
The present study describes the habitats, life cycle, larvae growth, burrowing behavior and terrestrial adaptation of Spadefoot toads in Israel based on observations and data collected during more than 30 years in nor... The present study describes the habitats, life cycle, larvae growth, burrowing behavior and terrestrial adaptation of Spadefoot toads in Israel based on observations and data collected during more than 30 years in northern Israel. The distribution area in Israel is from the north in the Upper Galilee and Golan Heights (annual rainfall range of 500 - 1000 mm) to the southern coastal plain (annual rainfall of about 250 mm). Among the 51 different breeding places of amphibians, only ponds where water was available for a few months were used by Spadefoot toads and metamorphosed populations were found around these ponds. The larvae underwent metamorphosis during the summer and autumn in northern Israel, and during the spring in central and southern Israel. A negative correlation exists between the percentage of toads burrowing and soil moisture levels, with greater burrowing behavior occurring under dry conditions. The plasma concentration increased during burrowing by electrolytes and urea accumulations. The burrowing behavior helped Spadefoot toads survive in this area at the southern border of its distribution. 展开更多
关键词 Breeding Places burrowING BEHAVIOR LARVAE Life Cycle Pelobates syriacus Plasma Concentration
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The effect of substrate grain size on burrowing ability and distribution characteristics of Perinereis aibuhitensis
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作者 Tao Sun Chun’e Liu +4 位作者 Xingzuo Li Dongzhengyang An Hairui Yu Zheng Ma Feng Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第12期52-58,共7页
Perinereis aibuhitensis(Grube, 1878) lives in marine sediments of estuary or shoal areas, where substrate has some crucial environmental factors affecting its burrowing and distribution. In order to provide basic data... Perinereis aibuhitensis(Grube, 1878) lives in marine sediments of estuary or shoal areas, where substrate has some crucial environmental factors affecting its burrowing and distribution. In order to provide basic data for the habitat selection and suitability evaluations of the artificial aquaculture of P. aibuhitensis, this paper conducted a quantified analysis of its burrowing ability and explored its behavioral preferences in different substrates,including mud(<75 μm), fine sand(125–250 μm), medium sand(250–500 μm), coarse sand(500–2 000 μm), gravel(2 000–4 000 μm) and ceramsite(4 000–8 000 μm). The research results revealed that substrate grain size significantly affected the burrowing time, burrowing rate, burrowing depth and distribution rate(P<0.01).Moreover, P. aibuhitensis demonstrated preferential selections relating to substrate grain sizes, had higher burrowing ability in ceramsite, mud and fine sand compared with other substrates. The strongest burrowing ability and the highest distribution rate were observed in ceramsite. The study indicated that P. aibuhitensis was sensitive to substrate grain size, which also had an impact on its burrowing process and population distribution.In the natural sea, substrates mainly composed of mud and fine sand are fit for aquaculture and stock enhancement. Based on behavioral preferences and ecological rehabilitation function of P. aibuhitensis, this paper proposes a symbiotic system of marine animals and halophytes, and constructs an ecosystem model of"Marine fish-Halophytes-Perinereis aibuhitensis" with P. aibuhitensis as the link. 展开更多
关键词 Perinereis aibuhitensis SUBSTRATE grain size burrowing ability distribution characteristics
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Impact of Human Disturbance on Fiddler Crab (<i>Uca tangeri</i>) Burrow Morphology, Distribution and Chemistry at Eagle Island, Niger Delta, Nigeria
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作者 Aroloye O. Numbere 《Open Journal of Marine Science》 2020年第4期191-202,共12页
<span style="font-family:Verdana;">Fiddler crabs are described as ecosystem engineers because of their burrow constructing ability. It was hypothesized that human activity will impact crab burrows. The... <span style="font-family:Verdana;">Fiddler crabs are described as ecosystem engineers because of their burrow constructing ability. It was hypothesized that human activity will impact crab burrows. The study area was delineated into lowly, medium and highly impacted plots. Crab holes were randomly counted and their width, length and surface area estimated. Burrow soils were collected and analyzed for Cadmium (Cd), Lead (Pb) and Zinc (Zn) using spectrophotometric method (HACH DR 890 colorimeter). The result indicates that burrow width was significantly different between impacted plots (P < 0.05). Lowly impacted plot had the largest width while highly impacted plot had the smallest width. In contrast, there was no significant difference in burrow length (P > 0.05), but highly impacted plot has the longest length while lowly impacted plot has the shortest length. Again, the surface area of crab burrow varies significantly (P < 0.05), and lowly impacted plot had the largest area (507.95 ± 61.84 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">) followed by medium (390.30 ± 57.65 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">) and high (265.16 ± 30.85 cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">) impacted plots. Similarly, lowly impacted area has more number of burrows (</span><i><span style="font-family:Verdana;">n </span></i><span style="font-family:Verdana;">= 55) followed by medium (</span><i><span style="font-family:Verdana;">n </span></i><span style="font-family:Verdana;">= 30) and highly (</span><i><span style="font-family:Verdana;">n</span></i><span style="font-family:Verdana;"> = 23) impacted plots. Highly impacted plot had the highest Cd and Pb concentration whereas lowly impacted plot had the highest Zn concentration. This implies that burrow morphology and chemistry exemplify the level of anthropogenic impact.</span> 展开更多
关键词 burrow Human Disturbance Heavy Metals MANGROVES Fiddler Crab Sand Fill
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Alpine grassland degradation intensifies the burrowing behavior of small mammals:evidence for a negative feedback loop
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作者 Zaiwei WANG Jiawen YAN +5 位作者 Amy MARTIN Dianne HBRUNTON Jiapeng QU Jin-Sheng HE Weihong JI Zhibiao NAN 《Integrative Zoology》 SCIE CSCD 2024年第2期240-252,共13页
Globally,grassland degradation is an acute ecological problem.In alpine grassland on the Tibetan Plateau,increased densities of various small mammals in degraded grassland are assumed to intensify the degradation proc... Globally,grassland degradation is an acute ecological problem.In alpine grassland on the Tibetan Plateau,increased densities of various small mammals in degraded grassland are assumed to intensify the degradation process and these mammals are subject to lethal control.However,whether the negative impact of small mammals is solely a result of population size or also a result of activity and behavior has not been tested.In this study,we use plateau pika as a model to compare population size,core area of colony,and the number of burrow entrances and latrines between lightly and severely degraded grassland.We test whether the alleged contribution of pika to grassland degradation is a result of increased population size or increased burrowing activities of individuals in response to lower food abundance.We found that grassland degradation resulted in lower plant species richness,plant height,and biomass.Furthermore,the overall population size of pika was not significantly affected by location in lightly and severely degraded grassland.However,pika core areas in severely grassland degradation were significantly larger and had significantly higher densities of burrows and latrines.Our study provides convincing evidence that habitat-induced changes in the behavior of small,burrowing mammals,such as pika,can exacerbate grassland degradation.This finding has significant implications for managing small mammals and restoring degraded grassland ecosystems. 展开更多
关键词 burrowing behavior grassland degradation plateau pika population size small mammals
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不同干扰强度高原鼠兔对高寒草甸土壤温室气体通量变化的影响
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作者 李婧 王苏芹 +1 位作者 谈昭贤 曲家鹏 《草业科学》 CAS CSCD 北大核心 2024年第1期207-217,共11页
高原鼠兔通过取食植物、排泄粪尿及掘土等行为对土壤理化性质及土壤微生物产生广泛干扰,进而可能会影响高寒草甸土壤温室气体排放。本研究选择高密度组(H)、低密度组(L)、对照组(CK)3种鼠兔干扰强度的高寒草甸为研究对象,揭示温室气体... 高原鼠兔通过取食植物、排泄粪尿及掘土等行为对土壤理化性质及土壤微生物产生广泛干扰,进而可能会影响高寒草甸土壤温室气体排放。本研究选择高密度组(H)、低密度组(L)、对照组(CK)3种鼠兔干扰强度的高寒草甸为研究对象,揭示温室气体排放速率对不同高原鼠兔干扰强度的响应规律及主要调控因素。结果表明,H组高寒草甸土壤CO_(2)排放速率为596.66 mg·(m^(2)·h)^(-1),显著低于CK组的695.45 mg·(m^(2)·h)^(-1)(P<0.05)。高原鼠兔干扰强度、地上生物量、土壤pH和土壤含水量是影响CO_(2)排放速率的主要调控因素。H组高寒草甸CH_(4)吸收速率为-43.46mg·(m^(2)·h)^(-1),显著低于L组的4.92mg·(m^(2)·h)^(-1)(P<0.05),H和L组高寒草甸N_(2)O排放速率分别为8.03、-2.39μg·(m^(2)·h)^(-1),均显著高于CK组的-16.69μg·(m^(2)·h)^(-1)(P<0.05)。土壤硝态氮和铵态氮含量、pH和含水量是影响CH_(4)吸收和N_(2)O排放的重要因素。因此,高原鼠兔干扰强度是影响温室气体排放速率的因素之一,进一步研究高原鼠兔对高寒草甸土壤温室气体排放速率的影响具有重要意义。 展开更多
关键词 高原鼠兔 有效洞穴密度 温室气体 植物群落 土壤理化性质 随机森林 青藏高原
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Burrow morphology of Uca uruguayensis and Uca leptodactylus(Decapoda:Ocypodidae)from a subtropical mangrove forest in the western Atlantic
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作者 Glauco B.O.MACHADO João B.L.GUSMÃO-JUNIOR Tânia M.COSTA 《Integrative Zoology》 SCIE CSCD 2013年第3期307-314,共8页
The continuous excavation of burrows by fiddler crabs generates bioturbation in the sediment,which can be estimated from burrow morphology.The aim of the present study was to describe the burrow morphology of Uca urug... The continuous excavation of burrows by fiddler crabs generates bioturbation in the sediment,which can be estimated from burrow morphology.The aim of the present study was to describe the burrow morphology of Uca uruguayensis and U.leptodactylus and its relationship with demography of resident individuals and to estimate the level of bioturbation in the sediment generated by each species.For all individuals from each of the 2 species,sex was determined and the carapace width(CW;mm)measured.Burrows were characterized according to burrow diameter(BD;mm),maximum burrow depth(MBD;mm)and burrow volume(BV;cm^(3)).The density of each species in the study area was also evaluated.In both species,the males were larger and occupied burrows with higher BV compared to females.Differences between sexes in relation to the burrow characteristics might reflect sexual dimorphism within the group and are probably related to the fact that males use the burrows for mating.BD and BV showed significant positive relationships with the size of resident crabs.The amount of sediment removed per burrow was estimated from mean BV:10.78 cm^(3)of sediment/burrow for U.uruguayensis and 12.38 cm^(3)of sediment/burrow for U.leptodactylus.Despite the density and depth differences between the 2 species,the similarity in burrow volume suggests that U.uruguayensis and U.leptodactylus present the same importance in terms of the bioturbation process.Burrow morphology is highly associated with characteristics of the occupant,although extrinsic factors should also be considered,and its description can provide estimates on the bioturbation generated by Uca species in mangrove forests. 展开更多
关键词 BIOTURBATION burrow structure crab burrowing fiddler crab
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不同缢蛏群体应对高盐养殖环境的潜沙和摄食响应能力
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作者 杜鑫鑫 牛东红 +3 位作者 张树源 邓敏 王杰 李家乐 《渔业科学进展》 CSCD 北大核心 2024年第3期203-213,共11页
为研究缢蛏(Sinonovacula constricta)生态行为应对高盐养殖环境的响应能力,以2个缢蛏群体(“申浙一号”群体SZSC和自然群体ZRSC)为实验对象,研究了不同盐度(20、24、28和32)对缢蛏群体潜沙行为、摄食生理的影响。对比2个群体潜沙指标... 为研究缢蛏(Sinonovacula constricta)生态行为应对高盐养殖环境的响应能力,以2个缢蛏群体(“申浙一号”群体SZSC和自然群体ZRSC)为实验对象,研究了不同盐度(20、24、28和32)对缢蛏群体潜沙行为、摄食生理的影响。对比2个群体潜沙指标和摄食率(FR)的差异,其中,潜沙行为实验设置盐度应激组(缢蛏从暂养池取出放进各盐度组开始实验)和胁迫组(缢蛏在各盐度条件下胁迫24 h后开始实验)。结果显示,SZSC的120 h半致死盐度为34.04,ZRSC的120 h半致死盐度为32.04。应激组中,SZSC的半数潜沙时间(BT50)显著大于ZRSC(P<0.05),盐度为24时,SZSC的BT50为4.2 min,显著低于盐度为28和32时的BT50;盐度为32时,SZSC潜沙深度分布更集中,潜沙率为88.33%,显著高于ZRSC(P<0.05)。而在胁迫组,SZSC中BT50显著低于ZRSC,潜沙率显著大于ZRSC(P<0.05)。摄食生理上,除对照组外,SZSC的FR均显著大于ZRSC(P<0.05),SZSC的FR在盐度为24时达到最大值[89.54 mL/(g·h)],显著大于其他盐度组(P<0.05)。研究表明,2个群体的生态行为均会受到盐度的影响,盐度越高,应激反应越强烈,其中,SZSC对高盐环境具有较好的耐受性。本研究从生态行为水平评估了2个缢蛏群体对高盐环境的耐受性,揭示了高盐养殖环境下缢蛏在底泥中的垂直分布情况和摄食能力,研究结果为进一步开展缢蛏耐高盐新品系的选育提供了理论参考。 展开更多
关键词 缢蛏 潜沙行为 摄食率 高盐
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Calcite Cements in Burrows and Their Influence on Reservoir Property of the Donghe Sandstone, Tarim Basin, China 被引量:12
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作者 齐永安 王敏 +1 位作者 郑伟 李妲 《Journal of Earth Science》 SCIE CAS CSCD 2012年第2期129-141,共13页
Abundant burrows of Skolithos linearis, Palaeophycus tubularis, and Taenidium barretti are preserved in the Upper Devonian Donghe sandstone of Tarim basin, China. They are commonly highlighted in core by the color of ... Abundant burrows of Skolithos linearis, Palaeophycus tubularis, and Taenidium barretti are preserved in the Upper Devonian Donghe sandstone of Tarim basin, China. They are commonly highlighted in core by the color of the burrow fill in contrast to the surrounding matrix and have dif-ferent textures and fabrics from the matrix. There are three kinds of calcite cements in burrows, microcrystalline-crystalline calcite cement, mosaic calcite cement, and ferroan calcite cement. Microcrystalline-crystalline calcite cement is widely distributed in the lower part of the Donghe sand-stone, but it is rare in burrows filling. It displays a globule structure under burial cementation and sel-dom replaces the quartz grains in shallow burial depth stage. Mosaiccalcite cement is widespread in the Donghe sansdtone reservoir of North Tarim basin. It shows chrysoidine, orange and bright orange lu-minescence, and intensely replaces the quartz grains, forming in early diagenetic and shallow burial depth stage. Ferroan calcite is asymmetrically distributed in the Donghe sandstone reservoir of Central Tarim basin. It fills the remanent pores in the shape of mosaic and replaces the quartz grains, matrix, and early calcite cement, forming in late diagenetic and deep burial depth stage. The burrows filled with white calcite cements have low oil saturation or may be oil-stained. In contrast, there is high oil saturation in the sandstone reservoir where the bioturbation is sparse or not present. With increased bioturbation, the porosity, permeability, and oil saturation decrease; thus, bioturbation intensity and reservoir property appear to be negatively correlated. 展开更多
关键词 burrow calcite cement Donghe sandstone reservoir property.
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黄河三角洲盐沼湿地螃蟹洞穴形态结构对土壤水盐运移过程的影响
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作者 解璐萌 查玟琦 +4 位作者 车纯广 李游蕊 李纪尧 刘佳凯 张振明 《生态与农村环境学报》 CAS CSCD 北大核心 2024年第6期831-839,共9页
明晰潮汐驱动下螃蟹洞穴对盐沼湿地水盐运移过程的扰动效应,对基于生态过程的黄河三角洲盐沼湿地保护与修复具有重要的理论及现实意义。研究结合野外调查和室内水槽模拟实验,探究潮间带螃蟹洞穴形态与分布特征,分析了潮汐作用下不同螃... 明晰潮汐驱动下螃蟹洞穴对盐沼湿地水盐运移过程的扰动效应,对基于生态过程的黄河三角洲盐沼湿地保护与修复具有重要的理论及现实意义。研究结合野外调查和室内水槽模拟实验,探究潮间带螃蟹洞穴形态与分布特征,分析了潮汐作用下不同螃蟹洞穴形态对水盐运移过程的影响。结果表明:(1)潮汐影响下,黄河三角洲潮间带螃蟹洞穴空间分布密度有差异,3条潮沟洞穴密度分别为(15.50±4.65)、(12.90±2.69)和(6.60±2.76)个·(0.25 m^(2))-1;(2)对螃蟹洞穴树脂模型进行简化归类,发现其主要形态结构为I型、L型、S型、X型、Y型,以上5种形态在获得的42个螃蟹洞穴中占比高达85.7%;(3)不同螃蟹洞穴形态在潮汐作用下土壤含水量变化趋势没有明显差异,而电导率随高潮与低潮呈现不同的升高与降低过程;(4)潮汐影响下,空白实验组潮汐水入渗量、孔隙水排泄量均显著低于有螃蟹洞穴的实验组,孔隙水排泄主要集中在水位下降时段,而L型洞穴因具有一定的储水能力,使更多的孔隙水在稳定时段排泄。(5)不同螃蟹洞穴形态对土壤盐排泄量有显著影响,S2、X和I组盐排泄量最高,空白组最低,仅为(0.403±0.003)g·d^(-1)。研究结果从水文学角度揭示了螃蟹洞穴的生态功能,将为后续的滨海湿地生态水文过程研究提供参考。 展开更多
关键词 黄河三角洲 盐沼湿地 螃蟹洞穴 水盐运移过程 模拟实验
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Motion Characteristics of the Appendages of Mole Crickets during Burrowing 被引量:1
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作者 Yan Zhang Jiafeng Cao +3 位作者 Qi Wang Pengfei Wang Yueying Zhu Junxia Zhang 《Journal of Bionic Engineering》 SCIE EI CSCD 2019年第2期319-327,共9页
Mole crickets,Gryllotalpa orientalis,have a pair of fully specialized forelegs for burrowing and employ an efficient underground excavating pattern,which provides excellent biological example for design of bionic unde... Mole crickets,Gryllotalpa orientalis,have a pair of fully specialized forelegs for burrowing and employ an efficient underground excavating pattern,which provides excellent biological example for design of bionic underground excavation equipment.In this study,the excavating pattern and kinematic features of mole crickets were obtained by using high-speed motion capture system and employing a transparent hydrogel as the analogue for soil.The two-dimensional motion characteristics of the forelegs of mole crickets during burrowing were captured and analyzed.The results show that the forelegs of the mole cricket employ a unique excavating pattern,which consists of foreword digging and horizontal expansion.We label this pattern a digging-expanding mode.An excavating cycle includes the digging and expanding motion of the forelegs,rotation caused by the midlegs and hindlegs,and forward thrust by the hindlegs.The excavating motion of the left and right forelegs is alternately carried out.This study can inspire the design of bionic tunnelling mechanisms and underground excavation equipment. 展开更多
关键词 BIONICS experimental biology MOLE CRICKET burrowING forelegs
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Burrowing Richardson's ground squirrels affect plant seedling assemblages via environmental but not seed bank changes 被引量:1
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作者 Levi J.Newediuk James F.Hare 《Current Zoology》 SCIE CAS CSCD 2020年第3期219-226,共8页
In grassland ecosystems,burrowing mammals create disturbances,providing habitat for animal species and increasing plant community diversity.We investigated whether seedling assemblages on Richardson's ground squir... In grassland ecosystems,burrowing mammals create disturbances,providing habitat for animal species and increasing plant community diversity.We investigated whether seedling assemblages on Richardson's ground squirrel Urocitellus richardsonii mounds result from seed rearrangement or environmental changes that favor germination of certain species over others.To test whether ground squirrels rearrange the seed bank by burrowing,we compared seed compositions among mounds,burrows,and undisturbed soil.To test whether ground squirrels change environmental conditions,we compared soil nitrate and bare ground cover on and off mounds.We also compared seedlings that germinated on mounds with seedlings that germinated on artificial disturbances from which we removed aboveground vegetation.Soil nitrate and bare ground cover were significantly higher on mounds than artificial disturbances.While seed richness and abundance did not differ among mounds,burrows,and undisturbed soil,seedling richness was reduced on mounds relative to artificial disturbances.Burrowing disturbance favors seedlings that can capitalize on bare ground availability but are less able to immobilize nitrate,as opposed to perennial species that immobilize more nitrate but take longer to establish.Our results suggest that Richardson's ground squirrels act as ecosystem engineers,although future research following succession on ground squirrel mounds is necessary to understand how they influence plant communities past the seedling stage. 展开更多
关键词 burrowing disturbance ecosystem engineering Richardsons ground squirrel seed bank SEEDLING species composition
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The effects of two free-floating plants (Eichhornia crassipes and Pistia stratiotes) on the burrow morphology and water quality characteristics of pond loach (Misgurnus anguillicaudatus) habitat 被引量:2
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作者 Jinqing Wang Guihua Fu +6 位作者 Weiyue Li Ying Shi Jicai Pang Qiang Wang Weiguang Lü Change Liu Jiansheng Liu 《Aquaculture and Fisheries》 2018年第1期22-29,共8页
Loach exhibit conspicuous drilling behaviors in the mud of shallow waters,yet their burrow morphology and the factors affecting this behavior have received little attention.We characterized the burrow morphology and w... Loach exhibit conspicuous drilling behaviors in the mud of shallow waters,yet their burrow morphology and the factors affecting this behavior have received little attention.We characterized the burrow morphology and water quality of the pond loach Misgurnus anguillicaudatus in three scenarios:in tanks without plants,tanks with the free-floating plant water hyacinth Eichhornia crassipes,and tanks with water lettuce Pistia stratiotes.Water hyacinth effectively removed water TN,COD,NO3-N and NH4-N,and water lettuce removed water TP and NH4-N.Water hyacinth and water lettuce markedly reduced water turbidity and DO,increased TOC and EC.Water hyacinth purified water more effectively than water lettuce,providing a suitable habitat for loach feeding,living and burrowing.The burrow structures were V-shaped,Y-shaped,inverted L-shaped,or complicated dendritic networks composed of multiple V shapes.The hyacinth treatment was characterized by the greatest burrow volume,length,depth,and structural complexity,but the opening size was reduced by dense root mat coverage.Burrows in the water lettuce treatment were characterized by intermediate volume,length,branches and sinuosity,but they had the largest opening and pit size.The control treatment had a flat bottom with the smallest,shortest burrows.This study indicates that free-floating plants improve habitat suitability and change burrow morphology and may be used to improve loach breeding methods。 展开更多
关键词 Freshwater benthic fish Misgurnus anguillicaudatus burrow morphology Free-floating plant Eichhornia crassipes Pistia stratiotes Water purification
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舀种勺舌式胡麻精量穴播器设计与试验
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作者 李辉 赵武云 +3 位作者 石林榕 戴飞 饶罡 王尊 《农业机械学报》 EI CAS CSCD 北大核心 2024年第3期85-95,共11页
针对胡麻播种机用种量大、播量变异系数大、播种不均匀的问题,基于胡麻种子物理特性和种植农艺要求,设计一种舀种勺舌式胡麻精量穴播器。通过分析穴播器工作原理确定穴播器组成、舀种勺结构参数范围及安装数量;对舀种勺舀种过程和清种... 针对胡麻播种机用种量大、播量变异系数大、播种不均匀的问题,基于胡麻种子物理特性和种植农艺要求,设计一种舀种勺舌式胡麻精量穴播器。通过分析穴播器工作原理确定穴播器组成、舀种勺结构参数范围及安装数量;对舀种勺舀种过程和清种过程进行力学分析,确定穴播器角速度范围;通过EDEM仿真过程得知,花纹内壁聚种斜槽在不影响舀种勺填充效果的同时,不仅可以提高仿真效率,还可以增大种子流动性,便于舀种勺充种。以穴播器角速度、舀种勺顶端过渡圆角半径、种室隔离板高度为试验因素,穴播器排种合格率、漏播率和重播率为试验指标,利用EDEM离散元仿真软件开展二次旋转正交组合试验,得到最优参数组合为:穴播器角速度2.9 rad/s、舀种勺顶端过渡圆角半径2.5 mm、种室隔离板高6.8 mm;将该舀种勺3D打印制作进行排种性能试验验证,台架试验得到该舀种勺排种合格率、漏播率和重播率平均值分别为87.00%、6.33%、6.67%;田间试验得到该舀种勺排种合格率为88.33%,漏播率为6.67%,重播率为5.00%;胡麻平均种植密度为50株/m^(2),其台架试验与田间试验结果基本一致,性能满足胡麻精量播种农艺要求。 展开更多
关键词 胡麻 精量穴播器 舀种勺 EDEM
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