蚂蚁觅食与搬运行为对阜平黄堇和小花黄堇种子散布的影响

蚂蚁是无脊椎动物中重要的种子传播者,蚂蚁散布影响植物种子的传播和扩散,进而会影响种苗的空间分布格局。在野外研究了蚂蚁觅食及搬运行为对阜平黄堇(Corydalis wilfordii Regel)和小花黄堇(C.racemosa(Thunb.)Pers.)种子散布的影响。结果显示,双针棱胸蚁和束胸平结蚁是两种植物种子的共同搬运者,前者行使群体募集,后者行使简单协作募集。在搬运阜平黄堇种子时,双针棱胸蚁在原地或搬运途中取食油质体后抛弃的种子约占种子总数的56%,而拖至蚁巢的种子约占种子总数的44%,平均搬运距离为(1.85±0.24)m,搬运效率为(43.8±7.5)粒/h;而束胸平结蚁将完整种子全部直接搬运至蚁巢,平均搬运距离为0.45 m,搬运效率为(7.3±2.2)粒/h。在搬运小花黄堇种子时,双针棱胸蚁和束胸平结蚁均将完整种子全部直接搬运至蚁巢,平均搬运距离分别为(6.27±4.40)m和(6.65±1.64)m,搬运效率分别为(34.2±6.5)粒/h和(10.6±3.2)粒/h。这说明行使群体募集的蚂蚁比行使简单协作募集的蚂蚁有较高的搬运效率,蚂蚁散布导致阜平黄堇和小花黄堇种子到达蚁巢的数量和搬运距离不同,而这种不同与相应搬运蚂蚁的觅食对策、搬运行为和种子特征有关。阜平黄堇种子比小花黄堇种子大,但阜平黄堇的油质体质量比小于小花黄堇的油质体质量比,讨论了种子特征对蚂蚁散布的影响。     

不同光照处理下青藏高原克隆植物黄帚橐吾(Ligulariavirgaurea)种子大小对其幼苗生长的影响

以高寒草甸克隆植物黄帚橐吾为实验材料,通过遮荫网模拟植被遮荫,研究种子大小与萌发及幼苗生长能力的关系和幼苗对光照条件的反应。结果表明：（1）在自然光照下,黄帚橐吾种子大小对种子萌发的影响显著,大种子的萌发率高于小种子。遮荫生境下,大、小种子萌发率有所降低,但遮荫对小种子萌发的影响比大种子显著。小种子的萌发率下降了近1/8,而大种子的萌发率仅下降了1/11。（2）黄帚橐吾种子大小对幼苗生物量积累影响显著,大种子幼苗总生物量（TB）大于小种子幼苗的。但生物量的分配与播种时间相关,播种后60 d,在自然光照条件下,大种子幼苗对根生物量的分配大于小种子幼苗,而对叶生物量的分配则正好相反。在遮荫环境中,大、小种子幼苗普遍对根的生物量分配增加,大种子幼苗根冠比（R/S）大于小种子幼苗。（3）黄帚橐吾种子大小对幼苗的生长也有明显影响。在自然光照下,小种子幼苗的相对生长速率（RGR）较大于大种子幼苗,但叶面积比率（LAR）、叶面积干质量比（SLA）、叶干质量（LWR）差别不明显。在遮荫条件下,幼苗的LAR、SLA、LWR显著增加,但大、小种子幼苗间差异不显著,幼苗的RGR减小,小种子幼苗的减小趋势大于大种子幼苗。     

不同光照处理下青藏高原克隆植物黄帚橐吾(Ligulariavirgaurea)种子大小对其幼苗生长的影响

以高寒草甸克隆植物黄帚橐吾为实验材料,通过遮荫网模拟植被遮荫,研究种子大小与萌发及幼苗生长能力的关系和幼苗对光照条件的反应。结果表明:(1)在自然光照下,黄帚橐吾种子大小对种子萌发的影响显著,大种子的萌发率高于小种子。遮荫生境下,大、小种子萌发率有所降低,但遮荫对小种子萌发的影响比大种子显著。小种子的萌发率下降了近1/8,而大种子的萌发率仅下降了1/11。(2)黄帚橐吾种子大小对幼苗生物量积累影响显著,大种子幼苗总生物量(TB)大于小种子幼苗的。但生物量的分配与播种时间相关,播种后60d,在自然光照条件下,大种子幼苗对根生物量的分配大于小种子幼苗,而对叶生物量的分配则正好相反。在遮荫环境中,大、小种子幼苗普遍对根的生物量分配增加,大种子幼苗根冠比(R/S)大于小种子幼苗。(3)黄帚橐吾种子大小对幼苗的生长也有明显影响。在自然光照下,小种子幼苗的相对生长速率(RGR)较大于大种子幼苗,但叶面积比率(LAR)、叶面积干质量比(SLA)、叶干质量(LWR)差别不明显。在遮荫条件下,幼苗的LAR、SLA、LWR显著增加,但大、小种子幼苗间差异不显著,幼苗的RGR减小,小种子幼苗的减小趋势大于大种子幼苗。     

休眠卵孵化对策与食物浓度对萼花臂尾轮虫(Brachionus calyciflorus)两品系干雌体种群增长的影响

周期性孤雌繁殖的轮虫靠休眠卵度过不良环境,等环境适宜时休眠卵孵化出干雌体,再次通过孤雌繁殖建立种群。通常休眠卵要经历一段休眠期再孵化,但也有些休眠卵生成后很快孵化,称为早孵化现象。有关休眠卵不同孵化对策如何影响其干雌体克隆种群的增长,目前尚不清楚。分别观测了萼花臂尾轮虫（Brachionus calyciflorus）的两个品系H1（窄温度生态位）和D1（宽温度生态位）的休眠卵在不同孵化对策和不同食物浓度下所生产的干雌体克隆群的种群增长差异。孵化对策包括早孵化（early hatching,EH）和晚孵化（late hatching,LH）;食物浓度包括高食物浓度（high food concentration,HF：2×10⁶个细胞/mL）和低食物浓度（low food concentration,LF：5×10⁵个细胞/mL）,每个品系下各设置4个实验组（LH-HF、LH-LF、EH-HF、EH-LF）,每组10个重复。结果发现,对D1品系来说：孵化对策和食物浓度对最大种群数量具有显著的综合影响（P=0.002）,但两因素间不存在交互作用（P=0.911）;早孵化的干雌体种群在最大种群数量上显著高于晚孵化的干雌体种群（P=0.001）。对H1品系：孵化对策和食物浓度对最大种群数量综合影响显著（P<0.001）,且两个因素之间存在交互作用（P<0.001）;高食物浓度下,EH干雌体克隆群的最大种群数量显著低于LH干雌体克隆群（P<0.001）。高食物浓度下干雌体克隆群开始有性生殖的密度阈值,D1品系EH组显著高于LH组（P=0.041）;而H1品系EH组却显著低于LH组（P=0.022）。最高种群密度下,H1品系的有性生殖率在两种孵化对策之间存在显著差异（P=0.044）,EH种群的有性生殖率低于LH种群,而D品系却未见有性生殖率在不同孵化对策间存在明显差异。本研究结果显示休眠卵的孵化对策会影响其后代干雌体种群的增长特性,其影响的结果可能与种群的生境适应相关。     

Response of ants to human‐altered habitats with reference to seed dispersal of the myrmecochore Corydalis giraldii Fedde (Papaveraceae)

Anthropogenic habitat disturbance has potential consequences for ant communities. However, there is limited information on the effects of ant responses on associated ecological processes such as seed dispersal. We investigated the effect of disturbance on the abundance, richness, and composition of ant communities and the resulting seed‐dispersal services for a herbaceous myrmecochore, Corydalis giraldii (Papaveraceae), in an undisturbed habitat (forest understory), moderately disturbed habitat (abandoned arable field), and highly disturbed habitat (road verge) on Qinling Mountains, China. In total, we recorded 13 ant species, and five out of these were observed to transport seeds. The community composition of dispersers was significantly different amongst habitats. The richness of the dispersers did not differ among the habitats, but their total abundance varied significantly across habitats and was 21% lower in the road verge than in the abandoned arable fields. The major seed‐dispersing ant species in both the forest understory and the abandoned arable field were large‐bodied (Myrmica sp. and Formica fusca, respectively), whereas the major seed‐dispersing ants found in the road verge were the small‐bodied Lasius alienus. This difference resulted in lower seed removal rates and dispersal distances in the road verge than in the other two habitats. The different dispersal patterns were attributed primarily to differences in dispersing ant abundance and identity, most likely in response to habitats with different degree of anthropogenic disturbance. The possible influence of disturbance on the ecological specialization of ant‐seed dispersal interaction is also discussed.     

荒漠孑遗植物裸果木种子时空扩散特性

裸果木(Gymnocarpos przewalskii)是亚洲中部荒漠区少有的第三纪孑遗物种,由于气候变化及人为干扰,其自然种群分布范围不断缩小。种子扩散作为植物生活史过程中的重要阶段,不仅对物种生存及其多样性至关重要,还影响物种分布范围和局部丰度。2015年和2016年分别在新疆哈密地区,采用布设种子收集器的方法,对其自然种群种子扩散的时空动态进行了定点连续观测。结果表明:该物种于当年6月上旬开始扩散,2015年略早于2016年。每年种子扩散持续时间约两个月,扩散趋势为单峰曲线,且呈集中大量扩散的模式,扩散高峰期与当年初次月降水高峰期吻合;在顺风的正南和东南方向上,种子扩散密度大且距离远;种子扩散主要集中在母株冠幅下,随着距母株距离的增加,种子扩散密度减少,二者间存在极显著的负相关性(P0.01),由于裸果木枝条繁多,对风力强度起到了一定的阻碍作用,可能是造成种子集中扩散在母株下的原因。裸果木种子扩散受外界环境(降水、风向)和自身因素等方面的影响,当种子在大量降水前完成扩散,将有利于种子在适宜的微生境萌发,是对多风、干旱的恶劣生境的一种长期适应。     

Fruits foraging patterns and seed dispersal effect of frugivorous birds on Hippophae rhamnoides sinensis

Behaviors of 18 species of birds eating fruits of Hippophae rhamnoides spp. sinensis were observed from September 2003 to March 2004. Their foraging patterns were found to be very different and can be divided into five classes: (1) direct swallowing the fruits on crown of the shrubs and sometimes regurgitating seeds soon after; (2) carrying the fruits to their perching sites and swallowing; (3) pecking the fruits from the shrubs to the ground, eating pulp and seeds but leaving pericarp; (4) pecking through the pericarp, eating pulp and leaving pericarp and seeds; (5) pecking through the pericarp on the top of fruits, and only eating seeds. These foraging patterns have different effects on seed dispersal of H. rhamnoides spp. sinensis. The germination experiment of three groups of seeds (seeds from feces, dry fruits and extracted seeds from dry fruits) was carried out. Although ingestion processes of birds had some adverse effects on the seed germination of H. rhamnoides spp. sinensis, the seeds from feces still have a relatively higher germination ratio. H. rhamnoides spp. sinensis provides food to a variety of frugivorous birds, and the birds disperse its seeds. Thus, a mutually beneficial relationship between the bird and the seed is formed. __________ Translated from Chinese Journal of Ecology, 2005, 24(6): 635–638 [译自: 生态学杂志, 2005, 24(6): 635–638]     

濒危植物大别山五针松母树林花粉传播规律

大别山五针松是典型的风媒传粉植物,花粉流是种群基因流的重要形式。用重力玻片法研究大别山五针松母树林的花粉飞散特征,分析了时间和空间对花粉飞散的影响,结合林分密度和气象因子探讨花粉飞散的特点。结果表明:大别山五针松从5月中旬开始传粉,散粉期为14d,盛粉期为3d,种植密度低的下坡花粉密度比密度大的上坡的要高。日散粉最大值出现在10:00～14:00,植株中上部花粉密度较高,距花粉源50m处花粉密度最高。建议对种植密度大的区域移栽以促进花芽生成,以保证结实率与提高种子品质。     

种子散布位置对格氏栲幼苗根系形态及生长特征的影响

种子从母株掉落于地面萌发后,其根系在不同散布位置(凋落物上层、土壤表层和凋落物下层)的生长形态影响幼苗定居及建成,而目前对其根系形态及生长特征的了解并不充分,限制了对幼苗根系在不同散布下适应策略的理解。为此,以格氏栲(Castanopsis kawakamii)为研究对象,通过模拟种子在凋落物中位置,设置凋落物上层(种子下层铺垫2 cm和4 cm凋落物,U2和U4处理)、土壤表层与凋落物下层(种子上层覆盖0、2、4、6 cm和8 cm凋落物,CK、D2、D4、D6和D8处理)等3种散布,探讨不同散布位置对格氏栲幼苗根系9个生长指标的影响。结果表明：(1)种子散布位置对幼苗根干物质质量具有显著影响,D2处理达最大值。(2)D2处理的幼苗根长、根表面积、根尖数、分枝数和比根长高于其它处理;根系平均直径在D6处理达最大值。(3)相关分析表明根长、根表面积、根尖数、分枝数和比根长与根系平均直径呈显著负相关关系。(4)对根系9个生长指标提取主成分后聚类为4个类群,D2与D4处理各划分一类;U2与U4处理划分一类,其余三个处理划分一类。综上所述,凋落物浅层覆盖(D2处理)适宜格氏栲根系生长;凋落物...     

云南拉沙山黑白仰鼻猴对种子传播潜力的评估

灵长类是森林生态系统中植物种子的主要传播者,有助于森林植被的更新,然而受研究方法的限制,灵长类种子传播潜力常被低估。为全面评估温带灵长类动物的种子传播潜力,采用直接观察法和粪便分析法评估珍稀濒危灵长类动物黑白仰鼻猴的种子传播潜力。于2018年11月—2019年10月采用直接观察法(瞬时扫描取样法)收集云岭省级自然保护区拉沙山黑白仰鼻猴的活动时间分配数据,获取每月取食果实的比例;同时每月收集黑白仰鼻猴的粪便,采用粪便分析法分拣猴粪中残留的植物种子,统计有完整种子残留的月份和粪便比例,应用这两种方法评估黑白仰鼻猴种子传播潜力及其差异。结果表明：直接观察法收集到黑白仰鼻猴取食果实的月份数为6个月(7—12月),月均取食果实的比例为(15.31±20.15)%,共取食13种果实;而粪便分析法发现黑白仰鼻猴粪粒内全年都有完整种子残留,粪便中月均完整种子残留比例(35.19±35.43)%,其中9月至第二年1月粪便中种子残留比例都大于50%,共取食18种果实;综合两种方法发现云南拉沙山黑白仰鼻猴共取食20种植物果实,具有较高的种子传播潜力。直接观察法可确定黑白仰鼻猴取食果实的物种数,而粪便分析法能...     

Effects of inflorescence size on visits from pollinators and seed set of Corydalis ambigua (Papaveraceae)

Female reproductive success (seed set) of a spring ephemeral plant, Corydalis ambigua Cham. et schlecht (Papaveraceae) was investigated in relation to inflorescence size and foraging behavior (frequency and duration of visitations) by pollinators (namely, overwintered queens of Bombus hypocrita sapporensis) by detailed daily observations of a natural population. Pollination experiments indicated that C. ambigua is self-incompatible and that seed set was significantly affected by the behavior of the pollinating queens. Plants with larger inflorescences were visited more often than those with fewer flowers. Fecundity also increased with increasing size of inflorescences. Visitation time (duration of foraging) rather than the frequency of visitations (number of visits) was critical for higher fecundity. Seed production was strongly enhanced by a few long visits (of more than 60 s), and seemed to be independent of large numbers of short visits (of less than 60 s). Hence, plants with larger inflorescences, which provide a conspicuous signal to pollinators and offer greater rewards in terms of nectar, received longer visits by B. hypocrita sapporensis queens and those plants exhibited higher fecundity.     

干旱沙区生物土壤结皮对红砂种子定居的影响及作用机制

为了探清干旱荒漠区生物土壤结皮对易漂移性植物种子定居影响及作用机制,以巴丹吉林沙漠南缘结皮前期以及藻类、地衣、藓类阶段结皮为场所,通过人工补充种子与野外长期监测的方法对红砂种子在生物结皮上流失动态、种子宿存微区特征以及种子宿存量与微区面积间的关系等进行研究。结果表明：(1)生物土壤结皮发育过程中,地表枯落物、微坑、龟裂缝、长藓的面积百分比均发生了显著变化,即：枯落物呈现出增大(藻类阶段)—稳定不变(地衣阶段)—减小(藓类阶段)的趋势,微坑、龟裂缝均先增大后减小(峰值在地衣阶段),长藓持续增大。(2)4个阶段的种子流失速度或定居率两两之间存在显著差异,流失速度大小依次为：结皮前期>藻类阶段>藓类阶段>地衣阶段,定居率大小为：地衣阶段>藓类阶段>藻类阶段>结皮前期。(3)生物土壤结皮上定居的种子仅宿存于枯落物、微坑、龟裂缝、长藓上,这4种微区上定居种子数与其面积之间均存在显著正相关关系,其关系均可用二次项y=ax²+bx+c(a≠0)表示,等面积微区内的定居种子数大小依次为：龟裂缝>枯落物>微坑>长藓。因此认为,生...