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1.
应用实验种群生命表数据分析毛竹林本土优势种竹盲走螨和引进种胡瓜钝绥螨对毛竹4种害螨南京裂爪螨、竹裂爪螨、竹缺爪螨、竹刺瘿螨的控制能力。结果表明①胡瓜钝绥螨取食上述4种害螨的世代存活率分别为90.4%、77.55%、87.93%、81.63%,每雌总产卵量分别为38.12粒、45.77粒、35.59粒、30.26粒,而乡土优势种竹盲走螨取食上述4种害螨的世代存活率分别为95.23%、100%、87.7%、80.48%,每雌总产卵量分别为44.5、46.8、41.15、20.1粒;②竹盲走螨以南京裂爪螨为猎物时其内禀增长率(0.155)与引进种胡瓜钝绥螨(0.154)相近,均明显高于南京裂爪螨(0.1089);③竹盲走螨以竹裂爪螨为猎物其内禀增长率(0.152)与胡瓜钝绥螨(0.152)相同但明显低于竹裂爪螨(0.192);④竹盲走螨以竹缺爪螨为猎物时其内禀增长率为(0.148)明显低于引进种胡瓜钝绥螨(0.175)和其猎物(0.185);⑤竹盲走螨取食竹刺瘿螨易大量逃跑,雌螨产卵量低,引进种胡瓜钝绥螨取食竹刺瘿螨能正常生长发育,但是其内禀增长率(0.144)明显低于其取食上述其余3种害螨的内禀增长率,产卵量高于当地种竹盲走螨,并描述1998年以来每年5—6月助迁人工繁殖的胡瓜钝绥螨控制毛竹害螨蔓延的效果。  相似文献   

2.
在25℃温度条件下,用黄金间碧竹(Bambusa vulgaris cv.vittata)叶饲养竹缺爪螨(Aponychus corpuzae Rimando),应用生存分析理论和多维矩阵模型组建竹缺爪螨种群生命表,计算得种群主要参数为:内禀增长率rm=0.0811,净增殖率R0=5.8368,平均世代长度T=21.7532d,周限增长率λ=1.0845/d;并分析了种群在不同年龄的生命状态,各发育期重叠情况以及稳定的年龄一阶段分布;最后讨论了应用这2种方法组建螨类生命表的优点。  相似文献   

3.
毛竹叶螨及其天敌捕食螨的生态位研究   总被引:3,自引:1,他引:3  
通过对福建南平西芹毛竹叶螨危害的毛竹林调查分析 ,结果表明 ,毛竹叶螨及其天敌对时空资源利用程度序列为 :捕食螨 (Bi =0 5550 ) >竹小爪螨 (Oligonychusurama) (Bi=0 4 467) >南京裂爪螨 (Schizotet ranychusnanjingensis) (Bi=0 30 97) >竹缺爪螨 (Aponychuscorpuzae) (Bi=0 2 875) >竹裂爪螨 (S .celarius) (Bi=0 1 674 ) >苔螨 (Bryobiasp .) (Bi=0 1 4 1 7)。捕食螨对南京裂爪螨、竹小爪螨、竹缺爪螨的时空跟随效应强 (Cij值分别为 0 574 3、0 4 830、0 4 371 )。叶螨间南京裂爪螨与竹缺爪螨对时空资源竞争最激烈 (Cij=0 60 76)。竹小爪螨与其它 4种叶螨竞争较激烈 (Cij>0 2 )。南京裂爪螨、竹小爪螨、竹缺爪螨 3种叶螨不同螨态中以竹小爪螨卵和成螨占有较大时空资源 ,其种内竞争激烈 (Cij值大 )。种间以竹缺爪螨和南京裂爪螨卵、幼若螨、竹缺爪螨幼螨与南京裂爪螨卵、竹小爪螨成螨与竹缺爪螨幼若螨竞争激烈 (Cij>0 4 )。捕食螨对 3种叶螨不同螨态的跟随效应以南京裂爪螨幼若螨、成螨、竹小爪螨成螨、竹缺爪螨幼若螨最强 (Cij>0 5) ,其余依次为竹小爪螨卵、南京裂爪螨卵、竹缺爪螨成螨、竹小爪螨幼若螨、竹缺爪螨卵  相似文献   

4.
竹子叶螨的生物学及其防治技术   总被引:15,自引:0,他引:15  
危害竹子的三种主要害螨——南京裂爪螨、竹裂爪螨、竹缺爪螨,在竹叶背织网或不织网危害,都在3月出蛰、11月入蛰。竹腔注药法具有经济、安全,防效达99%以上,为最佳防治方法。  相似文献   

5.
近年来南京地区竹锈褐斑病大量发生,该病对竹种的观赏价值和经济价值带来了一定影响.该病病原为南京裂爪螨.对竹锈褐斑病分别进行了化学防治和生物防治:(1)利用6种药剂对竹锈褐斑病进行室内毒力测定和野外防治研究结果表明:阿维菌素对南京裂爪螨的毒力最高,LC50为0.060 mg/mL,其次为哒螨灵、腚虫脒、炔螨特、四螨嗪,甲氨基阿维菌素苯甲酸盐最低.15%阿维菌素在浓度为1.2 mg/mL时具有较好的野外防治效果.(2)利用野外发现的天敌竹盲走螨属,按照益螨∶害螨比例为 1∶10、1∶30和1∶50野外释放结果表明:林间最适释放天敌比例在1∶10~1∶30之间.  相似文献   

6.
利用对竹叶可溶性糖、蛋白质、单宁和类黄酮含量的测定和毛竹叶部主要害虫种群的系统调查等资料。采用通径分析研究了竹叶4类化学成分对竹刺瘿螨、南京裂爪螨、竹缺爪螨、竹小爪螨、蠕须盾蚧和刚竹毒蛾等害虫的影响。结果表明:除竹刺瘿螨和南京裂爪螨外,竹叶化学成分对其余4种叶部害且:有着显著影响。这种影响主要表现为对各害虫种群的抑制作用;对于竹缺爪螨,直接作用以可溶性糖的影响最大,间接作用以类黄酮通过可溶性糖的影响较大;对于竹小爪螨,直接作用以单宁的影响最大,间接作用中则以类黄酮通过单宁的影响最大;对于蠕须盾蚧,直接作用以类黄酮的影响最大,间接作用以单宁通过类黄酮的影响最大;对于刚竹毒蛾,直接作用以蛋白质的影响最大,间接作用以类黄酮通过蛋白质的影响最大。  相似文献   

7.
林间调查分析结果表明:①南京裂爪螨丝膜数量消长与该螨种群一致,在年周期中有2个高峰期,分别是3月和9—11月,4—8月处于较底的水平;②丝膜数量与气温呈极显著相关(r=-0.6187);②一年中大多数时期南京裂爪螨丝膜呈聚集分布,仅5—8月呈均匀分布或接近于均匀分布,并具有明显的高度聚集分布—均匀分布—低度聚集分布—高度聚集分布周期;④丝膜的分布C值与气温及降雨量呈显著相关(r=—0.5403,—0.4530)。  相似文献   

8.
温度、光照对南京裂爪螨的影响   总被引:3,自引:0,他引:3       下载免费PDF全文
南京裂爪螨 (Schizotetranychus nanjingensis Ma et Yan)常与竹缺爪螨 (Aponychuscorpuzae Rimando)、竹裂爪螨 (Schizotetranychus bambusae Recb)等害螨共同或单独在毛竹(Phyllostachys pubescens Mazel et H.de L ehaie)叶背刺吸危害 ,造成竹叶早衰、早落[1~ 3] 。有关其生活习性及其发生与部分环境因子的关系以及防治技术 ,前人已作了研究[3~ 9] ,但未见光照对其存活、发育、繁殖的影响以及温度与其存活的关系等文献报道 ,本文就此作一研究报道。1 材料与方法1 .1 温度试验设置 - 1 0℃± 1℃、2℃± 1℃、2 0℃± 1℃、2 5℃…  相似文献   

9.
竹叶螨对毛竹危害的研究   总被引:3,自引:0,他引:3  
本文报道了南京裂爪螨 Schizotetranychus nanjingensis Ma et Yun、竹缺爪螨 Aponychuscorpuzae Rimando和锈螨 Eriophyes sp.的混合危害对毛竹光合作用和竹叶生长量的影响。研究结果表明 ,受害 5级竹叶片的叶绿素含量、光合作用强度和生长量分别下降 51.55%、79.6 %和 72 .6 %。新生竹叶明显变少、变小。受害程度愈重 ,表现愈明显  相似文献   

10.
亚洲象种群动态是研究者和管理者关注的最基本点,是种群研究的核心内容。以个体增长率、死亡率、年龄结构和性别比例为研究指标,2015年9至2016年12月,通过跟踪调查和定点观察,采取全事件取样法和焦点动物取样法,对西双版纳地区的亚洲象种群内禀增长力进行初步研究。调查结果,共观察到17个种群的227头亚洲象,其中幼体21头、青少年体37头、亚成体68头、成体101头。研究结果表明,亚洲象种群的雌雄比为3.39∶1,年度出生率、死亡率分别为26.92%、1.32%,均生殖率(Ro)为28.096,平均世代时间(T)为37.5 a,内禀增长率(rm)为0.038 6,周限增长率λ为1.039 3,实际增长率r为0.079 3。综合亚洲象的数量、年龄结构、性别比例、出生率、内禀增长率等参数,得出西双版纳地区亚洲象种群有较强的增殖潜力,但由于种群间的相隔,互不相连,阻碍了基因交流,不利于种群的繁殖,甚至面临近交的危险。  相似文献   

11.

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.  相似文献   

12.

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.  相似文献   

13.

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.  相似文献   

14.

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.  相似文献   

15.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。  相似文献   

16.

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.  相似文献   

17.
18.

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.  相似文献   

19.
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.  相似文献   

20.
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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