Observations on the taxonomic composition and vertical distribution of cyclopoid copepods in the central Red Sea

The taxonomic composition and vertical distribution of cyclopoid copepods, including very small species, in the central Red Sea were analyzed. Samples were taken in a multiple opening and closing net with 0.1 mm mesh size to a depth of 450 m. Most species belong to the genus Oncaea (13 identified and 6 unidentified forms). Nearly one half of these are smaller than 0.4 mm in length. Nine cyclopoid species and three groups of very similar species and forms of Oncaea predominate. In the upper 450 m of the water column, each of these species or groups account for more than 1 % of all cyclopoid specimens. In the epipelagic zone (0–100 m) Oithona simplex predominates, accounting for 20 % of the total. In the upper mesopelagic zone Paroithona sp. and one of the unidentified Oncaea forms are most numerous from 100 to 250 m, and two groups of Oncaea are most abundant from 250 to 450 m. The dominance of single species among cyclopoids is less pronounced than that reported for calanoids in the mesopelagic zone of the central Red Sea.     

The effect of temperature on the development times of eggs,naupliar and copepodite stages of five species of cyclopoid copepods

The duration times of eggs, combined naupliar instars and of the different copepodite stages of five species of cyclopoid copepods — Acanthocyclops robustus, Cyclops vicinus, Diacyclops bicuspidatus, Mesocyclops leuckarti, and Thermocyclops crassus — were investigated at five different temperatures. The five species can be divided in two groups: two species, C. vicinus and D. bicuspidatus, adapted to cold water conditions and three species, A. robustus, M. leuckarti and T. crassus adapted to warm water conditions. The cold water species showed a faster egg development than M. leuckarti and T. crassus at 5–15 °C. The eggs and instars of the warm water species M. leuckarti tend to develop faster than those of the former two species at higher temperatures. A. robustus showed the shortest egg and instar development at 10–25 °C. The warm water species T. crassus produced no eggs at 10 °C and temperatures below. At higher temperatures (20, 25 °C) the egg and instar duration times were similar or longer than those of the other species. When cultured in total darkness a great part of the C_IV respectively C_V copepodites of the summer forms entered arrest and the percentage of copepodites that showed an arrest of development was highest at lowest temperatures. The present results are compared with data from literature and differences are discussed.     

Survival and development of five species of cyclopoid copepods in relation to food supply: experiments with algal food in a flow-through system

1. Cyclops spp. generally develop and grow during favourable food conditions in spring and undergo a diapause in summer, while Acanthocyclops robustus, Mesocyclops leuckarti and Thermocyclops crassus develop and grow in summer when they face poorer food conditions and more competition from Cladocera. Since nauplii are the bottleneck in copepod development, we tested the hypothesis that Cyclops abyssorum and C. vicinus nauplii have higher food requirements for survival and development than the nauplii of A. robustus, M. leuckarti and T. crassus. We also tested survivorship and development from hatching to adulthood. 2. Survivorship and development of the copepods was studied in a flow‐through system using five concentrations of the phytoflagellate Chlamydomonas reinhardtii in the range from 1 × 10⁴ to 4.5 × 10⁵ cells mL^?1 (approximately 0.5–22.5 mg C L^?1). 3. Nauplii of both species of Cyclops died at intermediate to low (C. abyssorum) and low (C. vicinus) food concentrations, while nauplii of A. robustus, M. leuckarti and T. crassus survived at all concentrations. 4. The negative effects of low food concentration were also reflected in development. In C. abyssorum and C. vicinus, development duration increased at low food concentration while development was much less affected in A. robustus and T. crassus. Mesocyclops leuckarti was intermediate between Cyclops spp. and A. robustus/T. crassus, with an increase in development duration at the lowest food concentration. 5. Our results support the hypothesis that summer diapause in Cyclops spp. has developed as a strategy to avoid a food bottleneck for nauplii.     

A new genus and species of cyclopoid (Crustacea,Copepoda, Cyclopinidae) from a coastal system in the Gulf of Mexico

A new, monotypic genus of the interstitial marine cyclopoid copepod family Cyclopinidae G.O. Sars, 1913 is described from male and female specimens collected at Laguna de Términos, a large coastal lagoon system in the southern Gulf of Mexico. Mexiclopina campechana gen. et sp. n. cannot be adequately placed in any extant genus within the family. It differs from other cyclopinid genera in having a unique combination of characters including: 1) absence of modified brush-like seta on the mandibular exopod; 2) maxillule exopod with stout setal elements and brush-like setae absent; 3) basis of mandible with one seta; 4) presence of a modified seta on endopod of fourth leg; 5) fifth leg exopod unsegmented, armed with three elements in the female and five in the male; 6) intercoxal sclerite of first swimming leg with two medial spiniform processes on distal margin. The new genus is monotypic and appears to be most closely related to Cyclopina Claus, 1863 and Heptnerina Ivanenko & Defaye, 2004; the new species was compared with species of Cyclopina and it resembles Cyclopina americana Herbst, 1982 and Cyclopina caissara Lotufo, 1994. This is the second record of a species of Cyclopinidae in Mexico and the first in the Gulf of Mexico; the number of cyclopinid species recorded from the Americas is now 13.     

On the interpretation and application of mean times to extinction

As a metric of population viability, conservation biologists routinely predict the mean time to extinction (MTE). Interpretation of MTE depends on the underlying distribution of times to extinction (DTE). Despite claims to the contrary, all information regarding extinction risk can be obtained from this single statistic, the MTE, provided the DTE is exponential. We discuss the proper interpretation of MTE and illustrate how to calculate any population viability statistic when only the MTE is known and the DTE is assumed to be exponential. We also discuss the restrictive assumptions underlying the exponential DTE and the conditions under which alternative models for the DTE are preferable to the conventional (exponential) model. Despite superficial similarities between the exponential and alternative DTEs, several key differences can lead to substantially different interpretations of the MTE.     

黔中喀斯特次生林优势物种空间分布格局及关联性

以黔中天龙山2 hm²喀斯特次生林为对象,采用成对相关函数g(r)结合完全随机模型(CSR)研究重要值前4位优势树种的空间分布格局及其关联性。结果表明: 样地树种的径级结构呈倒“J”型分布,在优势树种窄叶石栎和圆果化香的影响下,第Ⅴ径级(≥10 cm)的数量较多。窄叶石栎呈现倒“J”型分布,种群更新良好,处于生长发育初级阶段;而圆果化香和云南鼠刺随着径级的增大数量逐渐递增,成年树、大树数量远多于幼树、小树,表明该种群更新不足,处于生长发育的中后期并逐渐衰退。除窄叶石栎外,其余优势树种整体呈现出在较大尺度上聚集分布,聚集程度随着尺度的增大逐渐下降并趋于随机分布,此规律在幼树径级中表现得尤为突出;而受各种因素的影响,各个树种不同径级呈现出不同的空间分布格局。在种间关联上,4个优势树种之间大多呈现负关联或者无关联关系,树种重要值越高与其他优势树种关联程度越低,呈现负关联的2个树种在小尺度上关联程度最低,随着尺度的增大负关联程度逐渐降低并趋向于无显著关联。     

Use of oxygen microsensors to measure the respiration rates of five dominant copepods and Euphausia crystallorophias furcilia from the Amundsen Sea,West Antarctica

The individual respiration rates of five biomass-dominant copepods (Calanoides acutus, Rhincalanus gigas, Metridia gerlachei, Calanus propinquus and Paraeuchaeta antarctica), and Euphausia crystallorophias furcilia, from the Amundsen Sea, West Antarctica, were determined using a Clark-type oxygen microsensor affording high temporal resolution. Measurements were conducted on specimens collected from waters exhibiting a very narrow temperature range (?1.68 to ?1.32 °C), at sites located between 71 and 75°S, during the summer (31 January–20 March 2012). A short incubation time (3 h) was sufficient to reveal significant declines in dissolved oxygen concentrations by 12–45%. The respiration rates of the copepods and E. crystallorophias furcilia were within the ranges of previously reported values. The respiration rates of relatively large-bodied species were rather low, whereas the smaller species generally exhibited higher respiration rates. The data show that this simple microsensor technique is a useful high-resolution non-invasive means of investigating the metabolism of zooplankton in the Southern Ocean. The method could be used in other situations when such information is required.     

贵州栽培笃斯越橘DSE真菌、AM真菌与ERM真菌空间分布研究

为探明贵州省栽培笃斯越橘根系深色有隔内生真菌（dark septate endophytes,DSE）、丛枝菌根（arbuscular mycorrhiza,AM）真菌与欧石南菌根（ericoid mycorrhiza,ERM）真菌的定殖及地理分布情况,揭示共生真菌在栽培笃斯越橘生长中的地位,本研究在贵州省笃斯越橘主栽区麻江县、凤岗县和高坡乡分别选取主栽品种圆蓝、粉蓝、奥尼尔和莱格西的根样及根围土样,观测不同地区不同品种根样DSE真菌、AM真菌和ERM真菌的定殖结构和定殖率,并测定土样土壤理化性质,分析不同真菌与土壤因子相关性。结果表明,3个地区的4个笃斯越橘品种均有DSE真菌、AM真菌和ERM真菌定殖,栽培笃斯越橘能与3类真菌形成共生关系,平均定殖率分别为61.11%、25.55%和22.50%。DSE真菌定殖率：高坡（62.50%）>麻江（61.66%）>凤岗（59.16%）;AM真菌定殖率：凤岗（34.14%）>麻江（25.83%）>高坡（16.66%）;ERM真菌定殖率：高坡（35.00%）>凤岗（20.00%）>麻江（12.5%）。相关性分析表明,DSE真菌中的菌丝与微菌核的定殖率呈负相关,AM真菌的总定殖率及定殖强度与微菌核的定殖率呈极显著正相关,与DSE真菌菌丝的定殖率呈负相关。ERM真菌总定殖率与DSE真菌菌丝的定殖率及AM真菌定殖强度呈极显著正相关,与DSE真菌总定殖率呈显著正相关。土壤有效磷与DSE真菌和ERM真菌总定殖率呈显著正相关,与AM真菌定殖率呈显著负相关。土壤铵态氮与DSE真菌中微菌核结构定殖率及AM真菌定殖率呈极显著正相关,与ERM真菌定殖率呈极显著负相关。土壤pH值与DSE定殖强度呈显著负相关,与ERM定殖强度呈极显著正相关。本研究分析比较贵州省3个笃斯越橘种植基地不同品种栽培笃斯越橘DSE真菌、AM真菌和ERM真菌的定殖及其与土壤理化性质之间的相关性,为贵州省栽培笃斯越橘的管理和发展提供技术基础和理论依据。     

秦岭皇冠优势灌木苦糖果的空间分布格局及种内种间关联

以秦岭皇冠暖温性落叶阔叶林25 hm²森林样地中的优势灌木苦糖果为对象,研究了苦糖果不同径级个体的空间分布格局以及种内种间关系。结果表明: 苦糖果径级结构呈现出下宽上窄的金字塔型,小径级植株数量最多,更新状态较好,处于稳定增长阶段,有利于群落更新和演替。以Ripley's K函数为基础,采用单变量和双变量成对相关函数,在3个零模型(完全空间随机模型、异质泊松模型和先决条件模型)的处理下,树种整体和不同径级以聚集分布为主,且聚集程度随研究尺度的加大而逐渐减小,逐渐趋向随机分布。受到生境异质性、扩散限制、负密度制约等影响,种内不同径级个体之间以正关联为主,但也有一定程度的无关联,未出现负关联的情况。种间关系较为复杂,既有无关联,也有正关联和负关联,但以负关联和无关联为主。     

吉林蛟河不同演替阶段针阔混交林木本植物幼苗空间分布与年际动态

幼苗的空间分布对群落更新具有重要意义。于2011年夏季在蛟河地区3个不同演替阶段针阔混交林样地内共设置了451个种子雨-幼苗观测样站,并于2012—2014年对幼苗样方内胸径1 cm的木本植物幼苗进行了连续3a的调查。对木本植物幼苗的数量分布以及水曲柳(Fraxinus mandshurica)、五角枫(Acer mono)、杉松(Abies holophylla)和东北枫(Acer mandshuricum)4个主要树种幼苗与大树的空间关系及其年际变化进行了分析,并用Syrjala检验分析了样站尺度上幼苗密度、丰富度空间分布在年际间的差异。结果显示:(1)木本植物幼苗的数量分布在不同群落和年际之间都表现出明显的差异,样站尺度上3个样地内的幼苗密度存在着较大的空间变异性,而幼苗丰富度的空间异质性较低。表明幼苗分布的空间异质性对幼苗密度有着重要影响。(2)样站尺度上幼苗数量和物种数的空间分布在不同年份之间是存在差异的。在一定程度上证实了种子产量、扩散方式和群落组成对幼苗空间分布的影响。(3))从死亡幼苗与大树空间关系来看,4个主要树种的死亡幼苗与成树表现出相似的分布格局,这既表明成体植株的空间分布特征也能够影响幼苗的空间分布格局,也从侧面说明了负密度制约效应对幼苗空间分布的影响。     

阿尔泰山小东沟林区乔木物种丰富度空间分布规律

对一定区域内生物多样性的合理保护往往需要在景观水平上了解生物多样性分布的总体规律.借助于典型抽样调查和遥感及地理信息系统相结合的方法来预测物种丰富度是定量研究生物多样性宏观分布规律的重要途径.以阿尔泰山小东沟林区为对象,在外业调查的基础上,选取主要气象因子、地形因子和植被指数(NDVI)作为预测变量,利用主成分分析和多元回归分析分别提取主要环境信息和构建物种丰富度预测模型,借助ArcGIS9.1的空间分析功能,得到了阿尔泰山小东沟林区乔木物种丰富度空间分布预测图,并利用残差图评价其精度.将小东沟乔木物种丰富度预测图分别与坡度、坡向和海拔图叠加,分析不同地形条件下乔木物种丰富度的空间分布规律.结果表明:占总研究区面积70.28％的区域,其乔木物种丰富度在3到4种之间.坡度0-5°的地形条件下乔木物种丰富度出现频率最高的数值是3,其余坡度条件下,乔木物种丰富度出现频率最高的数值是4;乔木物种丰富度在西坡和西北坡出现频率最高的数值是3,其余坡向乔木物种丰富度出现频率最高的数值均是4;海拔梯度上,乔木物种丰富度出现频率最高的数值呈现先增加后减少的趋势.残差类型面积统计表明,较强预测水平面积和中等预测水平面积占研究区总面积的94.62％,表明预测效果较好.     

1963-2012年新疆棉花需水量时空分布特征

研究基于新疆地区54个国家基本气象站1963-2012年的逐日气象资料,采用联合国粮食与农业组织FAO推荐的Penman-Monteith公式及作物系数法,计算了近50年来新疆棉花全育期和各生长阶段需水量。并利用线性趋势估计、MK检验、空间插值法对农作物全育期及各生长阶段需水量年际变化趋势和空间分布特征进行分析。结果表明：1）1963-2012年,新疆54个气象站棉花全育期平均需水量为759 mm,各站变化范围为555-1205 mm,差异明显。其空间分布整体呈现西北向东南递增、南疆大于北疆、东部大于西部的趋势。2）1963-2012年,在棉花的生长初期与发育期,全疆需水量空间分布总体由北向南增大并呈带状。在棉花的生长中期与生长末期,需水量空间分布表现为由西向东增大的格局。3）近50年棉花不同生长阶段需水量总体呈现下降趋势,并且除了生长中期下降趋势较显著外其他都不太明显。其中,生长中期下降速率最大为6.1 mm/10a,发育期及生长末期下降速率次之分别为2 mm/10a和1.3 mm/10a,生长初期下降速率最小,需水量以0.6 mm/10a的速率递减。4）新疆1963-2012年棉花全育期需水量总体呈下降趋势,递减速率平均约为5.3 mm/10a,并在1981年开始发生突变。5）全育期年需水量下降倾向率总体呈现与全育期平均需水量相同的空间分布特征,总体呈现北疆小于南疆、东部大于西部、由西北向东南递增的空间分布特征。     

豚草条纹萤叶甲各虫态的空间分布型

豚草条纹萤叶甲Ophraella communa LeSage是恶性入侵豚草(Ambrosia artemisiifolia L.)的天敌,用频次分布拟合和多种聚集指数测度等方法对该叶甲的成虫、幼虫和蛹、卵的空间分布型进行研究。结果表明,豚草条纹萤叶甲卵、幼虫+蛹、成虫的空间分布符合负二项分布,种群个体的空间分布为聚集分布。用几种衡量聚集度的指标,对上述各虫态分布的聚集程度进行测定;然后计算出各虫态田间最适理论抽样数。     

辽东山区次生林物种多样性的空间分布及尺度效应

以辽东山区次生林为研究对象,分析4 hm²样地Gleason丰富度指数、Simpson优势度指数、Shannon多样性指数和Pielou均匀度指数的空间分布特征及其与尺度的关系.结果表明: 4个多样性指数的空间分布均表现出较高的空间异质性;4个多样性指数的方差随尺度的增加其变化趋势有所差异;4个多样性指数的变异系数随尺度的增加呈下降趋势;乔木层的4个多样性指数值高于灌木层,且随尺度增加其变化趋势有所差异.在分析辽东山区次生林物种多样性时应考虑尺度效应.     

中国陆地自然植物有氧甲烷排放空间分布模拟及其气候效应

区域尺度陆地植物有氧条件下排放甲烷及其气候效应研究不仅对甲烷收支平衡研究具有重要意义,对于全球变化研究也具有重要推动作用。通过改进Keppler提出的公式,模拟了中国区域植物有氧甲烷排放的时空分布。利用IBIS模拟的NPP数据结合相关文献统计生物量与NPP的比值,计算得到中国区域自然植物叶片生物量,以及叶片甲烷排放。结果显示,2001年至2012年中国植物生物量与植物叶片甲烷排放量在Sres A2和Sres B1两种情景下差异不明显;但是气候变化模式差异的影响会随着时间的推移而扩大。在Sres A2情景下,中国地区年均植物生物量为10803.22Tg C,叶片生物量为1156.15Tg C。如果不考虑天气对光照的影响,植物叶片甲烷排放年均2.69Tg,约是全国年甲烷排放总量7.01%,是中国稻田甲烷排放总量的29.05%。在各植被类型中,草地叶片甲烷排放量最高,达到47.53%,其次是混交林。森林(针叶林、阔叶林、混交林)是主要的植物甲烷排放源,占中国区域植物甲烷排放总量的51.28%,其次是草地,占47.47%。中国区域植物叶片甲烷排放南高北低,东高西低的分布状态主要由地表植被覆盖类型决定,光照和温度也是重要影响因素。对Sres A2和Sres B1两种气候情景下中国植物甲烷排放预测分析,中国区域植物甲烷排放不断增加,在Sres A2情景下不同时期的平均增长率为9.73%,高于Sres B1情景的5.17%,且两种情景下的增长率都在降低。21世纪Sres A2和Sres B1变化情景下,年均植物排放的甲烷CO_2当量分别为83.18Tg和77.34Tg,约占中国年均CO_2排放总量的1.39%和1.29%。     

哥斯达黎加外海夏季表层浮游动物种类组成及分布

根据2009年7—8月在东热带太平洋哥斯达黎加外海(4°30’—10°24’N、91°20’—100°00’W)进行茎柔鱼探捕调查期间采集的表层浮游动物资料,对其种类组成、生物量及其分布进行了分析。结果表明,调查海域,鉴定出腔肠动物8目10科17属23种;甲壳动物8目30科43属74种;毛颚动物1目1科1属4种;尾索动物3目3科5属5种;环节动物为1目3科5属6种;软体动物1目1科3属3种;其他浮游动物有头足类的幼体、鱼卵和仔稚鱼以及浮游幼虫。调查海域总生物量和丰度的平均值分别为(124.78±176.83)mg/m3和(848±1219)个/m3,生物量较大的类群主要是甲壳动物的桡足类和毛颚动物的箭虫类其中桡足类的丰度(727个/m3)为最高,其次为箭虫类(373个/m3);出现频率较高的为桡足类、箭虫类、长尾类、头足类和鱼类仔稚鱼。     

秦岭优势乔木锐齿槲栎的空间分布格局及种内关联

为探究锐齿槲栎种群的空间分布特征及关联性,本研究以秦岭皇冠暖温性落叶阔叶林25 hm²森林样地内优势树种锐齿槲栎为对象,采用成对相关函数g(r)对其空间格局及其种内关联性进行了研究。结果表明: 锐齿槲栎径级结构呈“双峰”型,幼树(1 cm≤胸径DBH＜5 cm)个体数较多,种群呈增长型结构,更新良好;中树(15 cm≤DBH＜25 cm)比大树(25 cm≤DBH＜35 cm)、老树(DBH≥35 cm)的个体数略多,但远少于幼树和小树(5 cm≤DBH＜15 cm)。锐齿槲栎空间分布具有明显的海拔依赖性,主要分布在中高海拔地区。完全空间随机零模型分析表明,各径级个体在＜60 m的大尺度范围聚集分布。使用异质泊松模型剔除生境异质性分析表明,各径级的个体转变为大尺度的随机分布,表明树种的分布明显受到生境变化的影响。在＜40 m的小尺度范围内,径级差距小的个体间的空间关联性为正关联,径级差距大的个体间的空间关联性转变为负关联和无关联;在＞40 m的大尺度范围内,大径级个体间的空间关联性为正关联,而幼树和其他径级个体间的空间关联性为负关联或无关联。锐齿槲栎自身生物学特性和环境异质性是种群空间格局形成的重要原因。     

Variation in the life cycle of monogonont rotifers: Commitment to sex and emergence from diapause

1. A review of research on life-cycle events in field and laboratory populations of monogonont rotifers shows that there is great variation at multiple levels: (1) degree of sexual dimorphism; (2) occurrence and timing of sex; (3) propensity for sex during sexual periods; (4) factors controlling initiation of sex; and (5) timing and extent of emergence from diapause. There is no regular pattern where: (1) fertilised resting eggs hatch to start the growing season; (2) populations develop via female parthenogenesis during favourable conditions; and then (3) bisexual reproduction with resting-egg production occurs during later, unfavourable conditions.
2. Sexual reproduction in natural populations can occur throughout much of the growing season, be restricted to some period(s) during the growing season, or be completely absent. During sexual reproduction in both natural and laboratory populations, only some fraction of females produces males or resting eggs. This bet-hedging strategy can prevent a population crash and permits future population growth via female parthenogenesis. Selection against sexual reproduction, and rapid loss of sex, can occur.
3. Laboratory experiments with pond-dwelling species have identified specific environmental factors that induce sex in different species: (1) increasing population density; (2) dietary tocopherol (vitamin E) and (3) long photoperiods. These factors generally are associated with favourable conditions for population growth and production of energy-rich resting eggs: (1) large population size; (2) high probability of contacts between males and fertilisable females; and (3) nutritious diets. Endogenous factors can inhibit responses to these environmental inducers, and thus favour female parthenogenesis.
4. The timing of resting-egg hatching depends on: (1) occurrence of specific environmental conditions; (2) the minimum duration of obligate diapause; and (3) the genotype and physiology of females producing resting eggs. Hatching may occur shortly after oviposition, after a long diapause before or at the start of a new growing season, or throughout the growing season. Hatching can be massive and contribute substantially to population growth and genetic diversity.
5. Areas for future research include: (1) determining the timing and extent of sex and resting-egg hatching in more natural populations, especially those that are marine, benthic, sessile, and interstitial; and (2) identifying environmental and physiological factors controlling these events.

     

The history of crops and crop weeds in south-western Germany from the Neolithic period to modern times, as shown by archaeobotanical evidence

The results of more than 100 archaeobotanical investigations from south-western Germany have been arranged into chronological groups and analyzed with a spreadsheet to obtain presence data and the numbers of taxa present in the various time periods. They show an increase in the number of plant taxa cultivated in gardens since the Roman period, a decrease in the crops that were the earliest to be cultivated, especially emmer, and an increase of spelt, rye and oats in the course of time. New crop weeds appear, including an increasing number of southern plants originating from open vegetation. This is more likely to be a result of the intensification of agriculture than from increased human mobility. The crop weeds, grouped together according to their requirements for soil nutrients, show increasing soil acidification through the course of time.     

内蒙古退化草原狼毒种子的种群分布格局与散布机制

狼毒 (Stellera chamaejasme)为瑞香科多年生草本植物 ,是主要的草地有毒植物种类之一。采用邻接格子样方法和分布指数 (DI)以及平均拥挤度 (m* )指标 ,研究了内蒙古西辽河平原北部典型草原区内的狼毒 (Stellera chamaejasme)种子种群分布格局强度、类型与规模 ;根据顺序远离母株的取样调查 ,定量地分析了狼毒种子在 8个方向上的散布格局。结果表明 ,狼毒种子在落种期之前为随机分布 ,而在落种期结束后为聚集分布 ,种子种群斑块大小平均为 0 .0 8m2 。狼毒种子在 8个方向上的散布表现为不同的散布格局模式。在不同方向随着累积面积增加狼毒种子散布数量变化符合 L ogistic曲线增长。各方向种子散布数量与顺风风向频率显著正相关。狼毒种群具有“近母株散布”的种子散布机制 ,基本散布半径为 0～ 5 0 cm。狼毒种群通过种子散布扩展其分布空间的能力是很有限的