不同林分杨树云斑天牛种群空间格局地统计学分析

【目的】研究不同林分杨树林地云斑天牛种群不同虫态的地统计学空间格局,为不同林分杨树林地云斑天牛的防治提供理论指导。【方法】通过调查公路林、片林、渠道林和村庄林4种林分类型的杨树林地,以刻槽、排粪孔和羽化孔为调查指标,确定云斑天牛卵、幼虫、成虫(蛹)的种群数量,利用地统计学方法,研究不同林分不同虫态种群的空间格局。【结果】云斑天牛的刻槽、排粪孔和羽化孔在不同林分杨树林地的拟合模型分别为:公路林均为球形模型,片林均为指数模型,渠道林分别为指数模型、球形模型和高斯模型,村庄林分别为球形模型、指数模型和指数模型。不同林分类型云斑天牛各虫态的拟合半变异函数模型存在差异,但其指的定空间分布格局均为聚集分布。林分类型影响虫口的数量和分布,不同林分类型下各虫态的半变异函数模型和模型参数存在较大差异。云斑天牛危害片林时卵、幼虫和成虫(蛹)的变程a、块金值C_0、基台值C_0+C较其他3种林分类型的统计值明显偏小。【结论】危害杨树云斑天牛种群的卵、幼虫、成虫(蛹)在公路林、片林、渠道林和村庄林中均为聚集分布,即云斑天牛在不同林分杨树林地危害时各虫态的空间分布格局均表现为聚集分布。林分类型与云斑天牛聚集分布的习性关系不大,但影响相应虫态的半变异函数模型和模型参数。     

松墨天牛室内人工饲养及其生物学特性观察

在室内人工气候箱中对松墨天牛(Monochamus alternatus)进行人工饲养及生物学特性观察.结果表明:人工饲养条件下其羽化期为6～10d,交配2～4 d后产卵,雌虫平均产卵量60.5个;卵期为5～7d,卵的孵化率为85.95%;幼虫共5龄,1龄幼虫死亡率为25.89%,其它龄期幼虫很少死亡,幼虫化蛹率89.74%,蛹期为8～14d,蛹的羽化率为89.58%.成功建立了稳定的实验种群,实现了室内常年人工饲养,保证了实验虫源的供应,人工饲养和自然界松墨天牛的龄级一致,但人工饲养的天牛幼虫期、蛹期、羽化期、成虫帮命都大大缩短,成虫体形也较小,雌虫产卵数大大减少.     

团花绢野螟形态特征及生物学特性初步观察

团花绢野螟Diaphania glauculalis Guenée是危害团花树的重要害虫。采用室内饲养与林间调查相结合的方法,研究了该虫的生物学特性及形态,明确了团花绢野螟卵、各龄幼虫、预蛹、蛹和成虫的形态。室内卵集中产在养虫笼壁上,孵化率达98.3%,卵期约4~5 d。幼虫共5龄,低龄幼虫群集取食,食量较小,3龄以后幼虫开始分散危害,食量大增。老熟幼虫于叶片内结蛹室化蛹,蛹期7~9 d。雄成虫翅展略小于雌成虫。成虫羽化多集中于夜间,具有较强的趋光性。羽化第2天便可交尾,持续时间50~180 min,交尾翌日即产卵。     

丝带凤蝶长沙种群的形态特征及生物学特性

通过野外观察和实验室饲养相结合,研究了丝带凤蝶长沙种群的成虫、卵、幼虫以及蛹的形态特征、生活习性及生活史.结果表明;丝带凤蝶长沙种群一年发生6代,自10月中旬至翌年3月以滞育蛹于枯枝落叶中越冬,4月上、中旬越冬代成虫开始羽化,随后产卵.在25℃的条件下,卵、幼虫及蛹的发育历期分别为5.3 d、15.8～16.8 d和9.6～10.4 d;30℃的温度条件下,卵、幼虫及蛹的发育历期分别为4.0 d、12.9～14.6 d和6.5～7.1 d.在短日照条件下部分蛹进入滞育.此外,根据雌雄成虫的翅面特征认为丝带凤蝶长沙种群应属于南方型.     

九连山金斑喙凤蝶野外生物学特性观测

[目的]通过连续12 a对金斑喙凤蝶的野外调查观察,研究成虫活动规律,并利用仿生态养殖,观察金斑喙凤蝶卵和幼虫的形态特征与生活习性,研究其生物学特性,以期为金斑喙凤蝶研究与保护提供有效数据。[方法]根据2004—2012年对金斑喙凤蝶成虫活动规律的观察研究,2013—2015年,在金斑喙凤蝶成虫活动期,采用样线踏查的方法,自海拔450 m往山顶海拔1 200 m搜索,调查视野内木兰科植物分布情况,寻找卵和幼虫,收集后带回驻地进行仿生态养殖,观察其形态特征和生活习性。[结果]金斑喙凤蝶在九连山为一年二代,以蛹越冬,第一代成虫发生期为4月上旬至5月中旬,第二代成虫发生期为8月下旬至9月中旬;2013年在木兰科植物金叶含笑上发现卵和幼虫,2014和2015年在深山含笑上发现卵和幼虫,深山含笑为新发现寄主植物,目前除九连山外尚未有报道;幼虫5龄,各龄级幼虫差异较大;预蛹成蛹经历两次蜕皮过程,这是金斑喙凤蝶研究中的一项重大发现。[结论]1)金斑喙凤蝶卵和幼虫的分布与寄主植物分布密切相关,且对生境质量有较高要求,成虫活动范围主要在寄主植物分布范围及其周边;2)金斑喙凤蝶选择生长良好的金叶含笑和深山含笑叶片上产卵,或嗜食深山含笑;3)温度、湿度等环境因子对卵的孵化、幼虫的生长发育以及化蛹和羽化影响较大;4)金斑喙凤蝶雌蝶少,卵孵化率低,幼虫发育历期长,幼虫成活率低,化蛹和羽化率低等是导致其种群数量稀少的主要原因。5)据查,目前尚未有其它蝶类化蛹过程中经历两次蜕皮的报道,预蛹化蛹蜕两次皮是金斑喙凤蝶异于其他蝶类的特殊现象。     

新疆林木主要病虫害图象

瞿肖瑾绘六、园黄掌舟蛾危害榆树、杨树、桦树、橡树等。1成虫 2.卵 3.幼虫4.蛹 5.被害状八.弧目大蚕蛾危害杨树、五、杨=尾舟蛾危害杨树1威虫 2.卵 3.幼虫4.蛹 5.茧 6.被害状七、染雪毒蛾危害杨树1.成虫 2.触角放大 3.幼虫4.蛹 5.被害状丸、典皮夜蛾危害杨树新疆林木主要病虫害图象     

笋万纹象生物学特性的研究

笋万纹象是福建省毛竹林近年来的主要害虫之一.该虫在福建省2 a 1代,少数1 a 1代;以成虫在土茧中越冬,成虫4月上旬开始出土上笋,取食笋肉补充营养.经补充营养后4月中下旬开始交尾产卵,卵产于离笋尖40～80cm处的笋箨内,每笋产卵15～39粒,每雌产卵62～79粒.卵期5～7 d,幼虫期18～20 d,5月上、中旬老熟幼虫随被蛀枝梢落地,建土室化蛹.蛹期5～7 d,成虫期320～335 d.     

花斑皮蠹不同虫态对熏蒸剂的敏感性研究

为了搞清楚不同条件下采集的花斑皮蠹各虫态对熏蒸剂磷化铝的敏感性,采用密闭容器熏蒸法对其室内毒力进行测定,结果表明：成虫、4龄幼虫、老龄幼虫、蛹和卵的LD（50）,A组分别是4.95、7.39、25.14、26.43和34.09 g/m3;B组分别是10.94、16.13、38.25、43.13和43.25 g/m3。各虫态对磷化铝敏感性由强到弱依次为成虫、4龄幼虫、老龄幼虫、蛹、卵,连续使用磷化铝熏蒸防治花斑皮蠹,其耐药性明显提高。     

杨剑舟蛾空间分布型的初步研究

在调查的基础上,将获得的有关杨剑舟蛾成虫、卵、幼虫、蛹4个虫态的大量研究数据,通过统计分析得出杨剑舟蛾各虫态及其总体空间分布型为聚集分布,为进一步研究杨剑舟蛾的生物学特性、预测预报及其防治等提供理论根据。     

槐尺蛾研究初报

槐尺蛾食性单一,仅为害国槐、龙爪槐。该虫1 年发生5 ～6 代,以蛹在土中3 ～4 cm 处越冬。翌年4 月中旬成虫羽化,4 月下旬第1 代卵孵化,以后各代历期为25 d 左右。9 月中、下旬以第5 代幼虫或在10 月中、下旬以第6 代老熟幼虫入土化蛹越冬。幼虫共5 龄。3 龄前食量很小,3 龄后为暴食阶段,占总食量的95% 。药剂防治适期为2 ～3 龄期。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

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.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

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.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

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.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

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.     

CAD与建筑设计的关系

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。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

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.     

Risk Perception Among Non-industrial Private Forest Owners

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.     

Interactions in decomposition and N mineralization between tropical legume residue components

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.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

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.