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1.
狭鳕鱼皮脂肪酸组成分析及其营养评价   总被引:2,自引:0,他引:2  
为研究狭鳕鱼皮脂肪酸的营养价值,对狭鳕鱼皮的一般营养成分和脂质组成进行分析,同时采用气相色谱-质谱法对其脂肪酸组成进行分析和营养评价。结果表明,狭鳕鱼皮总脂含量为干重的6.09%,且总脂以甘油三酯(53.85%)和磷脂(25.54%)为主;脂肪酸组成丰富,以C16∶0、C18∶1n-9、C20∶1n-11、C20∶5n-3(EPA)和C22∶6n-3(DHA)为主,且C20∶5n-3和C22∶6n-3占总脂肪酸含量的27.64%;饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸三者之比为0.85∶1.00∶0.92,且脂肪酸致动脉粥样硬化指数和血栓形成指数分别为0.50和0.23,表明狭鳕鱼皮具有促进神经系统发育以及降血脂、抗动脉粥样硬化和抗血栓形成等功效。本研究为狭鳕鱼皮的营养评价及其产品的高值化综合利用提供理论依据。  相似文献   

2.
为优化辣木籽油脂的微波提取工艺并分析其油脂的营养价值,以辣木籽为原料,采用微波辅助提取技术优化辣木籽油脂的提取工艺,并通过傅里叶红外光谱、核磁共振碳谱及气相色谱-质谱技术对辣木籽油脂的脂质组成和脂肪酸组成进行分析。结果表明,辣木籽油脂的最佳提取工艺条件为提取溶剂二氯甲烷-甲醇(3∶2,v/v)、液料比7 m L·g~(-1)、提取时间10 min、提取温度70℃,在此优化条件下,辣木籽的油脂提取率为38.43%。辣木籽油脂的主要成分为甘油三酯,脂肪酸以油酸(C18∶1n-9,75.77%)、山嵛酸(C22∶0,6.74%)、棕榈酸(C16∶0,6.04%)和亚油酸(C18∶2n-6,5.30%)为主,是典型的高油酸型油脂,具有较高的营养价值和脂质开发潜力。本研究为辣木籽油脂的微波提取、营养评价和开发提供了一定的理论依据。  相似文献   

3.
n-3多不饱和脂肪酸具有多种重要生理功能,哺乳动物只能通过食物摄取n-3多不饱和脂肪酸,以满足机体的健康所需。脂肪酸去饱和酶-1基因(fatty acid desaturase-1,fat-1)以18~20碳的n-6多不饱和脂肪酸为底物进行脱氢反应,产生相应的n-3多不饱和脂肪酸,为了解转fat-1基因绵羊(Ovis aries)具体脂肪酸的组成,本研究利用fat-1表达质粒转染绵羊胎儿成纤维细胞,筛选获得阳性单克隆细胞系,通过体细胞核移植,得到转fat-1基因绵羊。通过脂肪酸质谱测定仪对5种组织脂肪酸含量进行测定,研究了fat-1基因对5种组织3类32种脂肪酸含量变化的影响。结果发现,在脑和臀肌中,饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸类别百分含量变化不显著;在肝脏、心脏和睾丸中,fat-1基因能够使饱和脂肪酸下降、使肝脏和睾丸的单不饱和酸量升高、使心脏中单不饱和脂肪酸含量降低;单不饱和脂肪酸中C18:1n-9c和饱和脂肪酸中C16:0、C18:0的含量变化决定了转基因绵羊组织单不饱和脂肪酸和饱和脂肪酸的变化趋势,在脑和臀肌中,这3种脂肪酸在转基因与对照组之间差异不显著;fat-1基因引起肝脏多不饱和脂肪酸降低,心脏和睾丸中多不饱和脂肪酸含量增高,主要由二十碳二烯酸C20:2(eicosadienoic acid,EDA)、二十碳三烯酸C20:3n-3(eicosatrienoic acid,ESA)、花生四烯酸C20:4n-6(arachidonic acid,ARA)、二十碳五烯酸C20:5n-3(eicosapentaenoic acid,EPA)和二十二碳六烯酸C22:6n-3(docosahexaenoic acid,DHA)的含量起主导作用;在5种组织中,转基因组EPA与DHA的含量均升高,尤其是EPA差异显著(P0.05)。fat-1基因降低了多不饱和脂肪酸中C20:3n-3和C20:4n-6的含量而增加了C20:5n-3和C22:6n-3的含量,从而提高了n-3/n-6的比值。本研究解析了转fat-1基因绵羊的脂肪酸组成和特点,对开发优质绵羊品种、改善人类膳食中脂肪酸结构及降低肥胖症风险提供了理论依据。  相似文献   

4.
为比较分析不同产地海带的脂肪酸组成,本研究采用溶剂法对海带总脂提取条件进行优化,并通过气相色谱-质谱技术对福州、宁波和青岛3个产地海带的总脂脂肪酸组成进行比较分析。结果表明,二氯甲烷-甲醇法提取海带总脂的效率较高,是海带总脂提取的理想方法;福州、宁波和青岛海带的总脂含量依次为0.75%、0.69%和0.86%,且无显著差异。从海带总脂中共鉴定出30种脂肪酸,以 C16:0、C18:1n-9、C20:4n-6(AA)和C20:5n-3(EPA)为主,且3个产地海带在脂肪酸组成上存在显著差异。福州产地海带中的C20:4n-6和C20:5n-3含量分别为10.12%、6.18%,其中C20:4n-6含量显著高于宁波(9.41%)和青岛(8.77%),C20:5n-3含量显著低于宁波(8.13%)和青岛(9.40%),进而使3个产地海带中的n-3 PUFA、n-6 PUFA、n-3/n-6、EPA+AA和EPA/AA等指标存在显著差异。本研究结果为不同产地海带总脂提取、脂肪酸比较分析及营养评价提供了一定的理论依据。  相似文献   

5.
赵倩  钟琪  徐盼盼  陈娟娟  杨锐 《核农学报》2019,33(5):917-926
为研究褐藻糖胶作为饲料添加剂对黄颡鱼幼鱼脂肪酸的影响,选取大小、体重相近的黄颡鱼幼鱼,随机分为对照组和试验组,对照组饲喂不添加褐藻糖胶的基础饲料,试验组饲喂添加0.1%褐藻糖胶的饲料,采用气相色谱质谱联用技术(GC-MS)分析不同喂养时间(1、2、4、8周)下试验组和对照组黄颡鱼幼鱼脂肪酸含量的变化。结果表明,黄颡鱼幼鱼体内共检测出15个总脂肪酸(TFA)和17个游离脂肪酸(FFA)。方差分析结果表明,黄颡鱼幼鱼TFA中C18:1 (n-9)、C20:4(n-5)和C22:6 (n-3)具有交互作用,而大部分FFA间都存在交互作用。喂养时间对黄颡鱼幼鱼脂肪酸有显著影响(P<0.05),随着喂养时间的延长,游离的单不饱和脂肪酸(MUFA)含量呈先减少后增加趋势,而总MUFA含量呈先增加后减少趋势;黄颡鱼幼鱼游离脂肪酸和总脂肪酸中饱和脂肪酸(SFA)均呈先增加后减少趋势,而多不饱和脂肪酸(PUFA)呈先下降后升高趋势。0.1%褐藻糖胶对黄颡鱼幼鱼TFA中C18:1 (n-9)、C20:4(n-5)和C22:6 (n-3)含量影响显著(P<0.05),对FFA组分含量的影响均显著(P<0.05),试验组黄颡鱼幼鱼SFA含量高于对照组,MUFA含量低于对照组,PUFA在喂养第2周时高于对照组,喂养第8周时低于对照组。此外,黄颡鱼幼鱼C20:3(n-3)/C22:6(n-3)的比值小于0.4,且喂养0.1%褐藻糖胶第8周时,黄颡鱼幼鱼C22:6(n-3)和C20:4(n-5)含量明显高于对照组,说明褐藻糖胶有益于黄颡鱼产卵和孵化,有助于黄颡鱼幼鱼的发育生长。本研究结果为黄颡鱼的健康养殖提供了基础数据。  相似文献   

6.
银杏花粉抗氧化成分的提取工艺优化   总被引:1,自引:0,他引:1  
为了开发银杏花粉深加工产品,以银杏花粉为试材,以其提取液的DPPH清除率为指标,研究加热回流法、超声波法、微波法、超声-微波法提取银杏花粉抗氧化成分的效果,并通过单因素和响应面法对微波法提取工艺进行优化。结果表明,4种提取方法中,微波法提取银杏花粉抗氧化成分的效果最好。微波提取的最佳工艺为:乙醇浓度59.38%、料液比1∶30、微波功率109.85 W、微波时间13 min。本研究为银杏花粉抗氧化成分的开发利用奠定了基础。  相似文献   

7.
超声辅助水热法提取牛骨油工艺参数优化   总被引:1,自引:1,他引:0  
为提高工业生产中牛骨油的提取率,以黄牛骨为原料,采用超声辅助水热提取法提取牛骨油。通过单因素及响应面试验研究牛骨油提取工艺,并对牛骨油的酸价、过氧化值及脂肪酸组成进行分析。结果表明,牛骨油提取的最佳工艺为超声功率300 W、超声时间50 min、超声温度100℃、热提温度125℃、热提时间90 min、料液比为(质量比)1∶1,此工艺条件下,牛骨油提取率可达98.86%。利用Design expert软件对影响牛骨油提取率的主要因素及其相互作用进行探讨,结果表明热提温度和热提时间对骨油提取率的影响显著大于其他因素(P0.01),料液比对骨油提取率的影响较小。与当前食品企业采用的牛骨油水热提取工艺相比,超声辅助水热提取法骨油提取率提高约12%。优化工艺得到牛骨油的酸价、过氧化值均小于GB10146-2015规定值,且脂肪酸含量不低于传统的水热提取工艺(不饱和脂肪酸(unsaturated fatty acid,UFA)总量和C18∶1n9c除外)。牛骨油中共检测出17种脂肪酸,C18∶1n9c、C16∶0和C18∶0是其主要脂肪酸,分别约达总脂肪酸的44%、23%和19%,饱和脂肪酸(saturated fatty acid,SFA)与UFA比值约为1∶1,UFA略高于SFA。研究结果为牛骨油的工业生产提供了理论参考。  相似文献   

8.
超声波辅助提取杠柳脂溶性成分工艺优化   总被引:1,自引:1,他引:0  
为了优化超声波辅助提取杠柳脂溶性成分的工艺,该文在单因素试验基础上,选取超声波功率、提取时间、液料比为主要影响因素,分析了3个主要影响因素对杠柳脂溶性成分提取结果的影响,应用响应面分析法优化了超声波辅助提取杠柳脂溶性成分的工艺方法,并使用GC-MS联用仪检测了杠柳脂溶性提取物的主要成分。结果表明:超声波辅助提取杠柳营养体脂溶性成分的最佳工艺为:在室温(20℃)及超声波频率20kHz条件下,提取试剂为石油醚,超声波辅助提取时间为70min,超声波功率为730W,料液比为1∶10g/mL。该工艺条件下,杠柳脂溶性成分的实际提取得率可达到6.14%。  相似文献   

9.
为分析罗氏海盘车性腺的单甘酯组成,本研究对单甘酯的衍生方法和色谱条件进行优化,并对单甘酯硅烷化衍生物的断裂规律和质谱特征进行分析,同时对罗氏海盘车性腺的单甘酯组成进行分析测定。结果表明,三甲基硅烷化法对单甘酯具有理想的衍生效果,且通过弱极性毛细管柱HP-5MS(30 m×0.25 mm×0.25 μm)对单甘酯硅烷化衍生物取得了理想的色谱分离效果。根据断裂规律和质谱特征,1-单甘酯硅烷化衍生物的特征离子为m/z 73、m/z 205、[M-103]+(基峰离子)和[M-15]+;2-单甘酯硅烷化衍生物的特征离子为m/z 73(基峰离子)、m/z 129、m/z 218、[M+H-162]+和[M-15]+。单甘酯硅烷化衍生物的色谱保留时间具有一定的规律性,其中2-单甘酯衍生物先于1-单甘酯衍生物出峰。同时,从罗氏海盘车中共鉴定出8种单甘酯,以1-单软脂酸甘油酯(1-C16:0-MG)和1-单硬脂酸甘油酯(1-C18:0-MG)等1-单甘酯为主,而2-单甘酯含量较低。本研究结果为单甘酯的衍生、色谱分析和质谱鉴定提供了一定的理论参考。  相似文献   

10.
王赵改  王晓敏  杨慧  张乐 《核农学报》2016,(10):1989-1996
为探讨微波辐射预处理提取香椿老叶总黄酮的机理,在单因素试验基础上,选择浸润时间、微波辐射时间、微波功率和汽化剂用量为自变量,以香椿老叶总黄酮得率为响应值,采用响应面法优化提取工艺,并借助扫描电镜观察细胞微观结构。结果表明,香椿老叶总黄酮最佳提取工艺为:浸润时间20min、微波辐射时间75s、微波功率420W、汽化剂用量3m L,此条件下香椿老叶总黄酮的提取率为7.97%。香椿老叶经微波辐射预处理后,细胞结构破坏严重,黄酮类化合物得到充分解吸,得率提高。因此,微波辐射预处理法能快速破坏植物细胞壁,后续提取时间缩短,得率提高,是一种理想的提取方法。本研究增加了香椿产业附加值,对微波辐射预处理提取香椿老叶总黄酮具有现实的指导意义。  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

13.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

14.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

15.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

16.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

17.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

18.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

19.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

20.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

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