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1.
高瑞东 《山西林业科技》2012,41(1):29-30,33
2008年至2010年,笔者对山西省芦芽山保护区普通翠鸟的生态习性进行了观察。结果表明:普通翠鸟在芦芽山地区为夏候鸟,每年4月上旬迁来,9月下旬迁离,种群密度为0.25只/km.5月初开始营巢,年产卵5枚~7枚。孵化期19 d~20 d,孵化率83.33%.雏鸟晚成性,26 d~28 d方可离巢活动。主要以小鱼、小虾等动物性食物为食。  相似文献   

2.
1998、1999年2~10月,在辽宁省朝阳县苏家营子对苍鹭的繁殖生态习性进行了观察研究。该鸟在辽宁省为夏候鸟,每年最早2月26日迁来,最晚9月28日迁离,居留期210d左右,产卵始期为3月21日,隔日1枚,窝卵数5—7枚,产出第1枚卵后开始孵化,孵化期24~26d,孵化率为92.3%。幼鸟为晚成鸟,育雏期40d左右。  相似文献   

3.
国槐新害虫——鸡血藤棕麦蛾生物学特性及防治   总被引:1,自引:0,他引:1  
首次记述鸡血藤棕麦蛾Dichomeris oceanis Meyrick危害国槐、龙爪槐和刺槐。该虫在山东商河1年发生2-3代,以3龄幼虫在国槐枝条皮缝、伤口内作茧越冬。幼虫卷缀或粘连叶片取食危害。成虫寿命2-14 d,孕卵量28-53枚,卵历期6-9d,蛹历期3.8-13 d。用5%吡虫啉3 000倍液和1.8%齐螨素5 000倍液喷雾防治幼虫,效果良好。  相似文献   

4.
芦芽山自然保护区岩鸽繁殖生态的观察   总被引:4,自引:1,他引:3  
于 1997、1998年 ,对山西省芦芽山自然保护区内岩鸽的繁殖生态和种群数量进行了观察。岩鸽间或有一年繁殖两窝的 ,巢多营建于悬崖峭壁的缝隙或洞穴中 ,有利用旧巢的习性。窝卵数多为 2枚 ,卵重平均 15 .6 7( 15 .0~ 16 .4) g。雌雄鸽均参加孵卵 ,孵化期 18d,孵化率 10 0 %,离巢率 87.5 %,巢内育雏 17d~ 19d,种群密度为15 .79只 / km  相似文献   

5.
1999~2004在牡丹江市西效林缘内对苍眉蝗莺繁殖生态进行了研究,苍眉蝗莺(Locustllafasiollata)每年4月下旬至5月中旬迁来,8月初迁走,居留期约3个月。繁殖期间,苍眉蝗莺的配偶关系为一雄一雌,筑巢一般由雌鸟,大约在4~5d内完成。筑巢期间交配。巢筑成后的4~5d开始产卵。每窝4~9枚,平均6枚,年产1窝。最后1枚卵产出后,进入孵卵期。孵化期约为12~14d。经亲鸟喂食10d左右羽毛齐满,20d可飞行,24d基本成鸟。  相似文献   

6.
灰鹡鸰繁殖生态的观察   总被引:1,自引:0,他引:1  
2005年5月-2007年5月对牡丹江地区灰鹡鸰的繁殖生态进行了研究,每年5月中旬到5月末迁来。居留期为140d左右,繁殖期间雌雄鸟共同筑巢,筑巢后6-9d产卵,每窝4-6枚,平均5枚。共同孵卵,孵化期约为12d。共同育雏,亲鸟喂食12d左右羽毛长满,16-17d飞行,24d基本成鸟。  相似文献   

7.
灰白蚕蛾(Ocinara variana)是榕属(Ficus)植物的重要害虫,在广州地区每年发生6代。在室温条件下(25—27℃)。卵、幼虫、蛹、成虫的历期分别为3~4d、12~15d、3~5d、和3~5d;雌虫产卵量约为30-400粒/雌。平均产卵量约为200粒/雌;种群数量一年有两个发生的高峰期,分别出现在4~5月和9~10月。  相似文献   

8.
花斑皮蠹生物学特性研究   总被引:1,自引:0,他引:1  
文章研究了花斑皮蠹的生活史、发生规律及生活习性。结果表明花斑皮蠹在陕西咸阳地区1年发生1~2代,以不同龄期的幼虫越冬,越冬代蛹期平均6.9 d,第1代蛹期4.7 d,第1代卵期平均9.8d,第2代卵期平均7.5 d,成虫平均寿命约15 d,每雌虫平均产卵量约51粒;幼虫化蛹历时60~80 min,孵化历时10~15 min,幼虫多6~7龄,龄期10~13 d;幼虫耐饥饿能力为初孵幼虫7~24 d,老龄幼虫1~2年,饥饿中的幼虫无互相残食的习性;饥饿365 d以上的幼虫其成虫生殖力下降60%以上。  相似文献   

9.
山噪鹛繁殖习性初步观察   总被引:1,自引:0,他引:1  
1996年—1997年在山西省蟒河自然保护区对山噪鹛的繁殖习性进行了初步观察。其繁殖期为每年的5月—8月,巢址多选择在阳坡灌木枝杈上,巢外径127mm~141mm,内径79mm~99mm,高70mm~85mm,深49mm~63mm,每巢有卵3枚~5枚,卵的长径为29mm~31mm,短径为18mm~21mm。育雏期15d。  相似文献   

10.
樗蚕在安徽省每年发生2~3代,而淮河以北均2代为主,极少发生3代。成虫羽化高峰为0~3时,群体羽化期长达40d,羽化率为6122%。每雌产卵数量约为276±505粒,遗腹卵142±511粒,雌成虫寿命4~10d,雄成虫寿命2~3d。卵期为8~9d,幼虫孵化高峰时刻为6~8时,孵化率高于95%,幼虫一般5龄,其全历期约30d。  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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