坚定的信念 无悔的选择——记安徽省郎溪县方里村林场场长刘傲柱

光阴荏苒，日月如梭，回首往事，历历在目。1984年春天，30岁出头的刘傲柱，英姿勃发，踌躇满志，怀着对林业事业的满腔热情来到安徽省郎溪县方里村林场，挑起了场长的重任。转眼间，28年逝去。如今，花甲之年的刘傲柱，白了头，驼了背，酸甜苦辣尝遍，却依然无悔当初的选择。     

春满莲花山

春天的北京延庆莲花山，一派醉人春色。郁郁苍苍的松柏，屏障似的勾勒出浓绿的背景。水灵灵的杏花，一树树地含丹吐霞，绣出繁花似锦的春的长卷。走过花林，带走花香，幻想出残红后的青杏、浓荫间的红果，酸甜可口。莲花山上的花岗岩，直立光滑，伸向天际。四面岩石合在一起，恰如映日的荷花，卷舒开合，挥洒天然。周围的石头平铺开去，完美地托出巨大的“花瓣”，形成接天的莲叶，随风摇曳，生机盎然。     

绿化树种垂枝柳病虫害防治技术

垂枝柳（ Salix babylonica L ．），别名水柳、倒挂柳等，乔木，树高10～20m ，小枝细、长，下垂，枝条直立的很少，深褐色。叶互生，叶披针形，长7～15cm ，宽4～11mm ，顶端渐尖，叶基部大多楔形，无毛或幼叶微有毛，有细的锯齿。雄蕊2，花丝分离，花药呈黄色，有腺体2个。雌花子房没有柄，具有腺体1个。蒴果，果内具有种子2～4粒，成熟的种子较细小，呈深绿色，外果皮具有白色柳絮。千粒重约0．1 g。花期4月，果熟期5月。     

山还是那座山——记甘肃省宁县瓦窑村农民杨兴成造林绿化事迹

他是强者，认准的事就矢志不渝，九折不回。他爱家乡，为了家乡山更绿，水更清，在山区耕耘不止，播绿不辍。他是地地道道的农民，尽管商海经营有道，事业有成，却放弃舒适的生活，植树不间断，让千余亩“不毛之地”披上了绿装。他，就是甘肃宁县湘乐镇瓦窑村农民杨兴成。     

印度尼西亚竹子栽培与利用

竹子在印度尼西亚广为使用，尤其是在乡村，因为它生长快，易采伐，使用方便，性能好。本文“印度尼西亚竹子栽培与利用”报道了目前印尼竹子的栽培、加工及研究、开发方面的进展。在印尼，许多竹种的栽植历史已有好几百年。传统的繁殖方法是用秆及鞭，而其它栽培繁殖方法尚处于试验阶段。可以这样说，印尼的竹子栽培研究尚处于早期的开拓时期。竹子在印尼有许多用途，如建筑材料，家具，墙，篮子，家庭器具，造纸，篱笆，手工艺品，农具，乐器及食品。目前，印尼竹子加工利用技术研究正处于全面的开发阶段。今后竹子作为工业用材的前景非常广阔，然而也存在一些问题。为提高竹子对乡村社会的贡献，促进竹子工业利用的发展，我们应该对竹子的生物学特性，营林，社会经济，新产品设计、开发，防蛀防霉，精加工等等进行更深入的研究。     

齐抓共管营造绿色家园

大地有山皆叠翠，山川无处不成林。进入甘肃省正宁境内，放眼望去，山川满目新绿，果园连片成带，村庄绿树掩映，瓜果花卉飘香，给人一种空气清爽、景象一新的感觉。十一届三中全会以来，正宁在林业生产中坚持改革开放，解放思想，突破旧体制，下放林权，调动了群众植树造林的积极『生，使全县林业迅猛发展，生态环境大为改观。全境气候宜，天蓝水清，基本未发生大的自然灾害，农作物连年稳产丰收。     

栾树的培植技术

栾树（Koelrenteria paniculata）又名灯笼树，属无患子科栾树属。落叶乔木，其树形高大而端正，树皮灰褐色，小枝稍有棱。无顶芽，皮孔明显。奇数二回羽状复叶，枝叶茂密而秀丽，春季红叶似醉，夏季顶端的大圆锥花序，黄花满树。秋叶鲜黄，蒴果膨大，成熟时红褐色或桔红色，果皮薄膜质，三角状卵形，似灯笼。种圆形，黑色。栾树适应性强，喜光，耐寒，耐干旱，耐瘠薄、石灰质土壤。耐一定盐渍及短期水涝。     

叶子花的栽培与花期调控技术

叶子花(Bougainvillea spectabilis Willd.)为紫茉莉科三角花属植物，又名三角花、九重葛等，原产南美巴西，为木质藤状灌木。叶互生，全缘，卵形，叶面深绿色、具茸毛；花小，黄绿色，位于三片大而红的苞片中，叶子花的苞片是主要的观赏部位，就是被人们称为花朵的部位，自然花期11月至翌年6月，瘦果具5棱，常见栽培的变种有深红三角花、白三角花、橙红三角花等。叶子花喜温暖、湿润和阳光充足环境，不耐寒，耐高温，过于阴蔽影响开花，对土壤要求不严，以肥沃的沙壤土最好，耐碱，耐贫瘠。叶子花苞片大而美丽，鲜艳似花，当嫣红姹紫的苞片展现时，给人以奔放热烈的感受，很受人们喜爱，现已成为国际上著名的盆栽植物。     

夏栎育苗及造林技术

夏栎(Quercus robur L)，别名长柄栎。属壳斗科栎属。原产于欧洲，1841年前后引进新疆伊犁和塔城栽培，至今已有160多年历史。夏栎树体高大，树干通直，枝叶茂密浓郁，树形优美，抗寒耐旱，适应性强，是珍贵的园林绿化树种和工业用材树种，其果可入药或作饲料，病虫害少，寿命可达1000a，深受群众喜爱。目前，新疆已用于城市绿化。     

名人植树爱树趣闻

百花山人与树有不解之缘。有树的地方可以没有人，但有人的地方一定有树。乡里人的门前屋后，田头路边，只要有块空地，总要栽上几棵树，于是人的整个身心就随着枝叶舒展，望着花蕾希冀，品着果实回味。即使无果可吃，后辈儿孙也能在大树底下乘凉。城里人没这福份，只好侍弄花草，聊作慰藉；培育盆景，以为寄托。一旦钱包稍鼓，就到处登因树而生机勃勃的山，游因树而充满灵性的水，观用树盖的楼台亭榭，也着自成一道风景的树。回去时，钱包虽空了，心里却实了，千姿百态的树就常常装饰着钢筋水泥结构中的梦……人与树相依伴也相互依存。人呼…     

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.     

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.     

Modelling of adequate pretwist for obtaining straight timber

Abstract

Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists.     

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.     

Biogeochemical impacts of clearfelling and reforestation on blanket-peatland streams: II. major ions and dissolved organic carbon

Streams and drains in blanket-peatland forest in western Ireland were sampled weekly over 5 years, 1996–2000, using continuous, depth-proportional passive sampling. Analysis was for pH, alkalinity by Gran titration, anions by IC, metals by ICP, aluminium speciation by loaded-resin exchange, and dissolved organic carbon (DOC) by absorbance at 320 nm.

Effects of felling are identified graphically from two forest drains whose catchments (both about 1 ha) were clearfelled, and partial clearfelling of one larger catchment (somewhat over 1 km²), in summer 1999. Calcium concentrations and alkalinity were increased in the drain- and streamwater from the felled areas. The pH was increased in drains, while in the larger stream, pH range decreased while the mean increased. Phosphorus increased markedly with clearfell, in the absence of recent fertilising, and also increased with fertilising; these results are reported in an accompanying paper. Ammonium-nitrogen concentrations were increased in the two drains with felling, and temporarily decreased in the larger stream. Nitrate increased in some cases. Potassium and manganese concentrations also increased. Concentrations of DOC and organic monomeric aluminium increased gradually, subject to a continuing strong annual cycle. There were no clearfelling effects on concentrations of solphate, suspended solids or inorganic monomeric aluminium. In the two drains (fully clearfelled), concentrations of sodium, chloride and magnesium, and conductivity, were all reduced after felling. Fertilising effects other than for phosphorus were indistinct.

Effects of the combined clearfell–reforestation treatment were testable statistically, using randomised intervention analysis, between two larger streams (1 km²) as a treatment–control comparison. There were statistically significant positive responses in streamwater concentrations of nitrate, potassium, calcium, DOC and aluminium fractions. The implications for management practice depend on whether the loss of nutrients is sustainable for future crop productivity, and whether critical limits and loads of receiving ecosystems are exceeded.     

Effect of Drought on Growth and Mortality of Actively Growing Norway Spruce Container Seedlings Planted in Summer

Survival, root egress and height growth of 13-month-old actively growing Norway spruce ( Picea abies (L.) Karst.) container seedlings exposed to preplanting drying treatments (0, 4, and 8 days) and postplanting drought periods (1, 2, 3, and 4 weeks) were studied in the field between 5 July and 18 August 1999. The mortality of seedlings increased and the height growth and root egress decreased throughout the postplanting drought period. Postplanting performance was also affected by preplanting drying treatments. The results indicate that no risk of excessive mortality and growth restrictions occurs when actively growing seedlings are planted in summer, provided that seedlings are well watered before planting and the drought period does not exceed 3 weeks.     

Rehabilitation of diseased cacao fields in Peru through shade regulation and timing of biocontrol measures

The objective of this case study was to test the effectiveness of biocontrol for the rehabilitation of abandoned, diseased (moniliasis, witches' broom and black pod) cocoa and to develop testable hypotheses regarding the effect of shade and biocontrol timing. Three trial fields differed in their shade regimes. Biocontrol was administered starting either at flowering or pod filling. Disease incidence and yield were compared with cultural control alone. Biocontrol reduced moniliasis from 49% to 25%, independent of the shading regime and application time. Witches' broom was most severe without shade and unaffected by biocontrol. No significant effects on black pod were observed. Although biocontrol increased percentage healthy fruit independent of shading and timing, only the shaded plot with biocontrol from flowering onwards responded with increased yield. Our hypothesis is: 'In the rehabilitation of abandoned cacao, only fields under sustainable shade management and early onset of biocontrol can realise their production potential.' 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.     

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.     

Defoliation by the Needle-shortening Pine Gall Midge,Thecodiplosis brachyntera,on Pines in Central Sweden

An outbreak of the needle-shortening pine gall midge, Thecodiplosis brachyntera , occurred on Scots pine, Pinus sylvestris (L.) and lodgepole pine, P. contorta (Dougl.) in central Sweden during 1995-1998. The larval feeding of T. brachyntera kills current-year needles and heavy infestation causes severe defoliation. A pattern of fluctuating defoliation among years and sites was found on both pine species. Defoliation was evenly distributed in the crown of P. sylvestris during years of high as well as low infestation; apical whorls had as much defoliation as basal whorls. In P. contorta , however, there was a tendency for defoliation to be concentrated on branches in the most apical whorls. Growth ring increments on P. sylvestris with high levels of defoliation (71%) did not differ from trees with moderate levels (26%) of defoliation. Shoot lengths were significantly shorter, however, on heavily infested trees the year after defoliation.