栗茶间作模式下茶树根系的基础特性

对安徽枞阳县周潭镇大山村中国森林生态网络大山试验示范区的栗茶间作茶园和单作茶园茶树根系的特征进行了试验研究。结果表明:栗茶间作促进了茶树根系的生长。间作茶园茶树根系的干重、吸收根比例、比根长和根系生理活性明显大于单作茶树根系;间作茶园茶树根系在土壤中的分布比单作茶树根系更深、更均匀;间作茶园内茶树和栗树根系在土壤空间中各自具有相对不同的生态位。栗茶间作具有较好的生态学基础,是一种可持续发展的茶园经营模式。     

间作对安吉白茶生长与叶绿素荧光动力学特性的影响

探讨薄壳山核桃与茶间作后安吉白茶生长和叶绿素荧光动力学特性差异，为构建薄壳山核桃和安吉白茶高效复合栽培提供理论依据。薄壳山核桃与安吉白茶间作分别以乔木树冠下(T1)、树冠缘(T2)、树冠外(T3)和纯安吉白茶园(T0)等4个测定点，测定10年生安吉白茶茶树新芽数、新稍生长量和单位面积产量等生长指标，结合茶树速生期(7—9月)叶绿素荧光动力学参数指标，分析探讨林茶间作不同光照条件下安吉白茶生长与叶绿素荧光动力学特征。结果表明(1)林茶间作茶树的新芽数、新梢长度等生长指标均显著高于纯茶园，其中乔木冠缘茶树生长指标较优；间作茶园茶树的百芽鲜(干)质量显著高于纯茶园，单位面积茶树新芽鲜质量以冠缘、冠外显著高于冠下和纯茶园，茶树新芽干质量为冠缘处最高，其次为冠外，冠下与纯茶园较低；(2)通过各测定点叶绿素荧光动力学OJIP曲线分析，7—8月高温强光下薄壳山核桃冠缘处茶树的荧光信号强度较强，8月纯茶园茶树的荧光点位显著低于间作茶树，9月各测定点茶树荧光曲线重合度较高。薄壳山核桃冠缘、冠外茶树相对可变荧光差异曲线(ΔV_t)波动较小，冠下茶树荧光的J相在7月快速下降但在9月却陡然...     

不同郁闭度对茶树净光合速率及茶园生态因子的影响

以安徽省金寨县栗茶间作园为研究对象,对不同郁闭度条件下茶树的净光合速率及茶园生态因子进行测定。结果表明:6月,露地茶园(对照)茶树的净光合速率在13∶00时出现"光合午休"现象,而有遮荫的茶园均未出现"光合午休"现象。在遮荫情况下,气温、土壤温度均低于露地茶园,且郁闭度越大温度越低;而空气湿度和土壤湿度均高于对照纯茶园,且郁闭度越大湿度越大。在郁闭度0.3的林下最有利于茶树生长和茶叶品质的提高。     

茶园间种泡桐生态及经济效益的研究

前言茶树原产于我国云贵高原亚热带—热带湿润季风地区。在强光、高温、低湿条件下,茶树生长不良,茶叶品质下降。近二十多年来,世界主要产茶国家先后致力于改变茶园生态环境而提高茶叶品质的研究。我国早在唐代、宋代就有了茶粮间作、茶桐间作的记载。1959年云南普文农场在热带茶园成功地建立了橡胶与茶树间作的胶茶人工群落。1970—1985年唐荣南、王融初分别成功地建立了湿地松与茶树、葡萄与茶树的人工群落。本试验试图选用强阳性、深根落叶阔叶树——泡桐与茶树间作,建立多层次的复合生态系统,改善茶叶品质,促使茶叶稳产高产,同时提供部分优质木材,取得较高的经济效益。     

北方茶林间作对茶树叶片组织结构和产量的影响

在山东泰安部分茶园做了间作板栗和银杏试验,结果表明,茶林间作郁闭度在0.3~0.4之间时,茶树叶片较对照上表皮增厚27%、栅栏组织增厚15.3%、全叶增厚3.1%,有利于抗旱、抗寒;茶林间作郁闭度在0.4~0.6之间海绵组织与栅栏组织的比值大、叶质柔嫩、持嫩性好,夏季茶叶产量可较对照提高89.8%;茶园间作银杏对茶树生长和鲜叶产量较有利。     

板栗、茶树间作观察与分析

板栗、茶树间作观察与分析板栗为喜光深根性高大落叶乔木，枝叶疏展，春季始叶于４月中下旬，秋季落叶始于１０月下旬，是我地采收秋果的主要经济树种之一。茶树为耐阴浅根性常绿灌木，是早春采制碧螺春茶的经济作物。一般而言，两者具有良好的共生条件。两者间作能提高单...     

崂山风景区公路边林茶间作对茶鲜叶铅含量的影响

研究了崂山风景区几条主要旅游公路两侧茶园中间作不同经济林树种对茶鲜叶Pb含量的影响。结果表明,调查区域单一种植的茶园的茶鲜叶均存在不同程度的Pb污染,离公路较近的茶园Pb污染较重,但茶园离公路的距离与茶叶Pb含量之间不存在显著相关关系。不同形式的林茶间作可以降低茶叶鲜采叶的Pb含量,茶园距公路愈近,或间作树种树冠覆盖率愈高,这种影响愈明显。公路边茶园临公路一侧建立林果隔离带也可有效地降低茶叶Pb含量。     

夷陵区茶杉混交型生态茶园建设与探讨

<正>夷陵区委、区政府非常重视茶区生态化建设,并将茶Camellia sinensis O.Ktze.杉Cunning lanceolata(Lamb.)间作、茶栗Castanca mollis-sima Blanco间作等作为退耕还林、农业产业化项目的主要经营模式来抓。近10年来,投入上千万资金扶持茶区生态化建设,目前已成林的混交茶园达0.33万hm2。茶区邓村乡从1990年开始营造     

茶叶与气象

茶叶是一种老少皆宜的饮品,它对气象条件特别敏感,若想达到最佳的饮用效果,必须考虑四季气候。云雾山中出名茶茶树是我国热带、亚热带地区最为普遍的经济树种,最适宜生长在温暖湿润、有遮荫的山区,弱光、遮荫的环境,既能促进茶叶内芳香物质的形成,又能抑制产生茶叶涩味的茶多酚类物质的积累,从而提高茶叶的品质。山区多云雾。这些悬浮在空气中的小水滴能够变太阳的直接辐射为散射辐射,使光量减少,强度削弱,适应了茶树喜弱光、耐荫的特性。高山云雾里,空气相对湿度一般在90%左右,茶树叶面蒸腾少,叶内粗纤维也少,加之降水充沛、土壤墒情好,既有利于茶树梢上的芽叶形成,又能使芽叶柔嫩,色味俱佳。山区的地形和植被,形成了良好的遮荫环境,使茶园里的太阳直接辐射时间减少,从而有利于茶树的生长和茶叶品位的提高。由此可见,自古流传的“云雾山中出名茶”的说法是有科学和事实依据的。您会贮存茶叶吗?茶叶的外形、颜色和内在质量受环境因素制约较大,影响茶叶色、香、味的环境因素主要是湿度、温度、光线三个气象因素。茶叶对湿度的要求非常高,室内空气湿度一般都大于70%,而茶叶里的含水量却不能超过5%;0℃-5℃的环境下,茶叶能较长时间保持原来的色泽和香味。茶叶最适合...     

油茶-茶复合模式对茶树光合特性的影响

为了揭示油茶-茶复合模式的生理生态学理论基础,分析了油茶-茶复合模式和纯茶模式内茶树叶光合特性日变化及季节变化的差异情况,并对茶树光合特性与生态因子进行了多元线性逐步回归分析。结果表明:纯茶模式内茶树净光合速率的日变化曲线为双峰曲线,即午休现象较为明显,而复合模式的为单峰曲线;从整体上看,纯茶模式内茶树叶片的净光合速率高于复合模式;气孔导度的日变化曲线,纯茶呈单峰曲线,而复合模式的呈双峰曲线;胞间CO2浓度的日变化曲线与净光合速率的基本相反,纯茶和复合模式的蒸腾速率表现为先上升后下降的变化趋势。多元线性回归分析结果表明,两种模式下影响净光合速率的主要因子都有气孔导度、胞间CO2浓度、蒸腾速率、空气相对湿度及空气温度,而油茶-茶复合模式的茶树还受到光合有效辐射的影响。     

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。     

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.     

Key Habitats in the Norwegian Production Forest: A Case Study

This study investigated the forest history, structural characteristics, the presence of fungal species suggested to indicate ecological continuity in old-growth forest, and the species composition of saproxylic beetles in 30 old forest ''woodland key habitats'' (WKHs), and compared them with production forest in the same age-class in south-eastern Norway. No statistically significant differences in forest characteristics, community of saproxylic beetles or number of red-listed beetles were found between the WKHs and the production forest, probably owing to a combination of profound long-term logging and a lack of will to delineate sufficiently large WKHs in the one area with significantly less forestry impact. The study indicates the advantage of including forest history information in WKH selection where such data exist, and the importance of restoring habitats in heavily exploited forest landscapes.