北京鸢尾属修订

本文收录了北京地区鸢尾属植物共5种，3变种。其中黄菖蒲、喜盐鸢尾、蓝花喜盐鸢尾为《北京植物志》未曾收录的种类。作者在此基础上对北京鸢尾属植物进行修订，编写了分种检索表，对新增补种类的特征进行了描述。     

鸢尾属观赏地被植物在亚热带生态园林中的应用

分析研究了适合亚热带地区的10种鸢尾属观赏地被植物的生态特性与景观效果,结果表明,在中国亚热带地区,鸢尾属种类可划分为冬春功能群和夏季功能群两大类,其中鸢尾、蝴蝶花和德国鸢尾适合春季观赏,其余种类适合在春夏观赏;在春季,溪荪的光合速率最高,德国鸢尾和黄菖蒲次之,蓝蝴蝶花和白蝴蝶花最低;蒸腾速率的顺序也为溪荪最高,蓝蝴蝶花和白蝴蝶花最低;德国鸢尾由于相对较高的光合速率和相对较低的蒸腾速率,水分利用效率最高,花菖蒲则因相对较高的蒸腾速率和相对较低的光合速率,水分利用效率最低.     

净化生活污水的浮床植物筛选

【目的】筛选出目前对生活污水净化效果较好的浮床植物。【方法】以14种湖南常见的草本和木本植物为材料,监测了污水处理过程中植物的株高、根系结构和生物量等生长指标,CODcr、TN、NH3-N、TP等水质指标的动态变化,并进行了植物的生长指标与水质净化指标的相关性分析。【结果】1)大部分植物均有较强的生长能力,其中水葱、水蕹菜的株高具有显著性优势(P <0.05);美人蕉、再力花、菖蒲和梭鱼草均表现出极强的生根能力,其根长增长率分别为390%、293.33%、286.67%和270%;植物的生物量增长率在5.1%~500.7%之间,其中菖蒲、美人蕉、水蕹菜和再力花的生物量具有显著性优势(P <0.05)。2)无植物对照组对污染物的去除率明显低于有植物处理组,处理时间的长短对污染物的净化效果具有显著差异性(P <0.05),且主要表现为早期对污染物净化速率快。所有植物处理对CODcr、TN、NH3-N、TP的平均净化率比无植物对照组分别提高了6.30%~36.80%、11.92%~20.97%、22.92%~29.28%、5.51%~41.24%,其中,美人蕉对CODcr的净净化率高达36.80%,水蕹菜对TN、TP的净化效果表现出显著性优势(P <0.05),梭鱼草则对NH3-N具有较好的净化能力。3)根据筛选指标的平均隶属函数值对14种草本和木本植物进行聚类分析,可将植物分为高、中、低净化能力植物三大类,高净化能力植物:梭鱼草、菖蒲、美人蕉、鸢尾、水蕹菜和再力花。中等净化能力植物:花菖蒲、旱伞草、黄菖蒲、花叶芦竹和水葱。低净化能力植物:冬青、女贞和月季。【结论】草本植物中的梭鱼草、菖蒲、美人蕉、鸢尾、水蕹菜和再力花以及木本植物中的冬青对生活污水具有较高的净化能力,适合用作生活污水处理的浮床植物。     

鸢尾属7个品种花粉活力及柱头可授性研究

为探索鸢尾属不同品种的花粉活力及柱头可授性的变化规律,从而提高其杂交效率,以鸢尾属7个品种为试验材料,对其开花过程中不同时间的花粉活力和柱头可授性进行观测,并对其结果进行UPGMA聚类分析。结果表明,7个鸢尾品种花粉活力最高期与柱头可授性最高期在时间上不吻合。‘贵格少女’开花后2h花粉即散尽,6-8h柱头可授性保持最高;蓝蝴蝶、黄菖蒲、马蔺、‘音箱’、‘紫褐’和‘平瓣粉’分别于花后2h、2h、4h、6h、6h、6h花粉活力达到最大值,4-24h、4-26h、4-24h、6-8h、6h、6-8h柱头可授性保持最高。在欧式距离D2=2.68处,7个鸢尾品种可分为两大类,第一类包括4个品种,按相似度依次为‘音箱’、‘平瓣粉’、‘贵格少女’和‘紫褐’。第二类包括3个品种,按相似度依次为黄菖蒲、马蔺、蓝蝴蝶。     

水位变动对2种水生植物生长及生物量分配的影响

通过人工模拟自然水位变化,设置水位变化控制试验,研究不同水位梯度处理对2种水生植物菖蒲和黄花鸢尾株高、分株数、生物量积累及生物量分配格局的影响。试验结果表明:不同水位梯度对2种水生植物的株高、克隆分株数、生物量积累与分配格局等指标均有显著影响(P<0.05);菖蒲和黄花鸢尾株高在变动水位处理下均显著高于其他水位(P<0.05)处理,高水位有效促使菖蒲的克隆分株,各水位对黄花鸢尾克隆分株数无显著影响。变动水位和高水位处理对菖蒲的叶质量有显著影响,且明显高于中水位和低水位。黄花鸢尾根生物量在各水位处理中无显著差异(P>0.05),根茎生物量在变动水位下显著高于高水位和低水位下生物量。综合来看,变动水位更有利于2种水生植物的生长及发育。     

退耕还湿湿地对水质的净化效果研究

以桂阳县柏树河退耕还湿试点项目区内的还湿湿地为研究对象,根据植物生物学特性和试点区水质状况,因地制宜,选择合适的植物进行了优化配置,以提升项目区生态净化功能、改善进入项目区的水质。结果表明:柏树河退耕还湿湿地对COD、TN、TP、NH+4-N、NO-3-N的降低率分别为61.3%、78.6%、57.1%、66.3%和48.1%;"黄菖蒲+花菖蒲+水生鸢尾+水生美人蕉+风车草+水葱种植区对COD、TP的去除效果最好,湘莲+茭白种植区对TN的去除效果最好"。故退耕还湿湿地可有效净化水质,减少农业面源污染。     

宝鸡市植物专类园调查与分析

对植物专类园在宝鸡地区的分布现状做了进一步调查与分析,着重介绍了专类植物展示和植物造景形式在园林中的重要地位,专类园不仅可以用于科学研究,还可以展示本种植物的群体美和个体美,同时也为游人提供了游览休憩的场所。并对专类园的现状及存在问题进行了分析与评价,提出了专类园设计与营造的发展对策。     

南京中山植物园的特色专类园设计

要使南京中山植物园在新的形势下有所发展 ,适应和满足社会的需求 ,必须对其进行新一轮的调整、规划与改造。在改造和规划下 ,要十分注意地被植物园、水生植物园、孢子植物园、盲人植物园、创意园、腊梅园、球根花卉园和鸢尾园等特色植物专类园的规划与设计 ,该文简要地介绍了这些特色植物园     

杭州地区鸢尾属引种繁育技术与湿生鸢尾应用研究

介绍鸢尾属植物的品种分类系统和通常园艺上的分类方法,以及引种原则、方法及驯化措施;对引入栽培的鸢尾品种进行形态特征、生物学特性观察试验,并以7种湿生鸢尾为代表品种进行繁育技术研究及应用效果调查,分析其在杭州环境条件的生长发育情况,为湿生鸢尾类植物在与本地区的生产应用和气候环境相似的其他地区进一步推广应用提供科学的依据和参考。     

桂花专类园植物景观综合评价

选择长江流域建成多年的3个桂花专类园为研究对象,利用AHP的方法,以景观质量、生态效益和服务功能3个准则层为主,建立了桂花专类园的植物景观评价体系;并对30个群落样地进行了景观评价。结果表明:准则层的权重值从高到低为生态效益>景观质量>服务功能,综合评价指数的平均值从高到低为上海桂林公园(82.60%)>南京灵谷寺公园(78.10%)>苏州桂花公园(68.60%)。结果显示:该评价体系适合于植物专类园的植物景观评价,尤其是可利用定量分析的评价结果来更好地指导植物专类园的植物景观设计。     

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.     

Decomposition and nutrient loss from prunings of different contour hedgerow species in tea plantations in the sloping highlands of Sri Lanka

Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week⁻¹ for leaves and from 0.0225 to 0.0633 week⁻¹ for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.     

Growth of Phlebiopsis gigantea in wood of seven conifer species

Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.     

Effects of Seed Weight and Seed Type on Early Seedling Growth of Pinus sylvestris under Harsh and Optimal Conditions

The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions.     

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。     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B₁ and B₂ vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B₁ 88 mg 100 g⁻¹, B₂ 187 mg 100 g⁻¹, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.     

Growth of Mixed Birch-Coniferous Stands in Relation to Pure Coniferous Stands at Similar Sites in South-eastern Norway

Mean age, mean and top heights and yield were studied in 20 mixed stands of birch ( Betula pubescens Ehrh. and B. pendula Roth) and Picea abies (L.) Karst. and nine mixed stands of birch and Pinus sylvestris L. in south-eastern Norway. Each mixed stand and the adjacent pure coniferous stand (control) were growing under the same site conditions and had not been commercially thinned. There were no significant differences in mean age at breast height or in top heights between birch and conifers in the mixed stands, while mean height was significantly higher for birch than for spruce. A growth index was calculated based on total volume and age at breast height. For the spruce sites the growth in young mixed stands (birch < 17 m) was superior to that of pure spruce, while the difference was insignificant in older stands. The growth index correlated positively with the ratio between generatively and vegetatively regenerated birch trees, and negatively with the age of the oldest species in the mixture and with site quality. For the pine sites there was no significant difference in the growth index between mixed birch-pine and pure pine stands. A mixture effect of birch on the volume yield of spruce or pine could not be demonstrated.