浅析乡村古典园林的修复与利用

对乡村古典园林内涵和现状进行分析,表明在保护、修造过程中存在不受重视、缺乏乡土性和整体性等不足之处,提出在修造过程中应注意保留当地宝贵的乡土文化、保持其历史文化特质等观点;探讨如何将乡村建设、发展与乡村古典园林的保护、修缮有机结合,并加以开发利用等问题,以提高乡村古典园林对当地传统文化和传统艺术的承载力。     

粤东山区客家美丽乡村的地域性植物景观营造

目前我国美丽乡村建设仍存在忽视乡村自然环境建设保护的迫切性、植物景观乡土性和地域性缺失、乡土农耕文化保护和传承不够等问题,与外国尤其英国、德国存在明显差距。以粤东山区客家乡村为例,通过实地调查研究和美丽乡村建设实践,提出以乡村山林田、公共建设区和村居房前屋后等植物景观建设为主,在保护乡村自然植物资源和生产性农田生态体系前提下,通过挖掘应用当地特色品种创新发展生产体系,依托当地植被营造乡土植物景观,优化村居植物环境特色,拓展乡村公园格局融入周围自然景观,以构建和重塑美丽乡村园林与自然植物生态体系,凸现地域性植物景观和文化风貌特色。     

甘肃皋兰什川古梨园农业文化遗产保护对策研究

甘肃皋兰什川古梨园作为首批入选的中国重要农业文化遗产,以其悠久的栽培历史、独特的古法种植技术和富有内涵的梨园文化闻名于世。在新时代乡村振兴战略实施中更具有保护传承和利用发展的价值与意义。但由于古梨园比较效益的下降,基础设施、管理模式落后,已生存500多年的古梨园保护与发展面临严重的威胁。本文按照国家对农业文化遗产保护与发展的要求,从古梨园文化遗产保护与发展问题入手,融合相关专业规划,对古梨园保护与发展的经营管理模式、基础设施建设、绿色产业发展、农业文化推介进行了研究,为古梨园传承与保护、人与自然的和谐发展、相关产业的绿色发展提出对策建议。     

基于园林学视角的美丽乡村规划建设探析——以古人墩村为例

围绕当下最热门的美丽乡村建设问题,从美丽乡村的定义出发,对美丽乡村的地理差异、文化差异、经济差异进行了阐述,从园林学视角对乡村的生态性、文化性、地域性和可持续性进行了相关的解读。以古人墩村美丽乡村的建设为例,从园林学的角度探讨了美丽乡村建设过程中的一些问题,并提出了相关的建议,以期为相关的美丽乡村建设提供参考。     

楠溪江古村落古树名木保护

该文通过楠溪江国家级风景名胜区内岩头、埭头、苍坡等古村古树名木保护与利用实践,提出保护理念及措施。       

民居：乡村的美和魅

在浙东楠溪江两岸 ,人们称杨梅为楠。想像梅子黄了的时节 ,江上绿波泛香 ,碧水如带 ,楠溪江该不逊于梅子姑娘吧 ?识香而来 ,陈志华先生到楠溪 ,确有他的真爱 ,那就是他一生衷情的乡村古建筑———《楠溪江中游古村落》 ,一本厚厚的图文并茂的书 ,在三联书店的前厅看到她时 ,我立刻被她所吸引。确实 ,即使当我静下心来要写出下面的文字时 ,我仍然激动于她一见钟情般打动人心的力量。事实上 ,就像一个长途奔波的旅人怅望夜色将拢时的最后一抹晚霞 ,是她所散发的乡土气息 ,是这气息中乡村的美和魅 ,召唤并吸引了我。这里 ,乡村民居突破了一家一…     

乡村景观保护与规划探讨

分析了乡村景观保护与规划现状及存在的问题,从理论研究、法律法规、乡土特色等方面提出了乡村景观的保护和规划措施、方法,对乡村景观保护与规划具有一定的参考作用。     

乡村景观保护与规划探讨

分析了乡村景观保护与规划现状及存在的问题,从理论研究、法律法规、乡土特色等方面提出了乡村景观的保护和规划措施、方法,对乡村景观保护与规划具有一定的参考作用。     

基于低造价理念的高品质园林建设应用

随着国家对美丽中国,美丽乡村的提出,对资源的节约和环境的保护也提出了较高要求,这就要求在城市绿化建设方面,既要达到园林的美观,又要达到对资源的节约。而将低造价理念应用在园林建设中就顺应了我国建设资源节约型和环境友好型社会的基本国策。本文就目前我国园林建设中存在的浪费问题进行了分析探讨,并分析低造价理念在园林建设中的应用,达到高品质地景观效果并减少浪费。     

江南丘陵传统乡村聚落的生态图示语言——以浙江楠溪江为例

选取浙江楠溪江古村落作为江南丘陵传统乡村聚落的典型代表,以生态图示语言为切入点,通过理论研究结合卫星遥感影像图判读方式,分析其自然景观图示语言、文化景观图示语言、网络化图示语言和生态流与生态过程,最终归纳总结出江南丘陵传统乡村聚落空间格局的图示特征和生态演变的主要过程.     

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.     

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 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.     

Ectomycorrhizal inoculation of Douglas-fir transplanted container seedlings with commercially produced inoculum

Commercially produced vegetative inocula of Laccaria laccata and Hebeloma crustuliniforme successfully formed ectomycorrhizae with Douglas-fir transplanted container (plug+1) seedlings. After 4.5 months in containers, 83% and 90%, respectively, of short roots were mycorrhizal. L. laccata- or H. crustuliniforme-inoculated seedlings had significantly more mycorrhizal and total short roots than Pisolithus tinctorius-inoculated (4% mycorrhizal root tips) or uninoculated control seedlings. No significant differences were detected in seedling growth at the end of the container phase.After transplantation and growth in nursery beds for 17 months, mean new short root colonization of all seedlings was 80%. H. crustuliniforme persisted as a dominant mycorrhizal fungus on seedlings initially inoculated with this fungus. L. laccata-inoculated seedlings had 40% of their short roots colonized by L. laccata and another 40% by native fungi Rhizopogon and Thelephora spp. All mycorrhizae of control seedlings and those inoculated with P. tinctorius were formed by fungi native to the nusery beds. A significant fungal treatment effect was detected for shoot height only. Control seedlings were significantly taller than L. laccata-inoculated seedlings after transplanting.This article is part of senior author's thesis in partial fulfillment of the Ph.D. degree in the Department of Forest Science at Oregon State University, Corvallis.     

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.     

Protein diversity ofPaulownia plant leaves and clusters

Paulownia tomentosa, P. fargesii, P. lamprorhylla, P. albiphloea, P. australis, P. fortunei, P. elongata, P. elongata f. alba andP. albiphloea varchenggtuensis were classified into three groups:P. fortunei group (P. fortunei andP. elongata f. alba);P. australis group (P. australis andP. albiphloea varchenggtuensis) andP. tomentasa group (P. tomentasa, P. fargesii, P. albiprhlaca, P. lamproprhylia andP. elongata) accordance to the results of the single and two-dimensional SDS-PAGE of protein in thePaulownia tree leaves. The result could lay a foundation for classifying the GenusPaulownia plants. Foundation Item: This paper was supported by National Nature Science Foundation of China and Nature Science Foundation of Henan Province. Biography: FAN Guo-qiang (1964-), male, Professor in Institute ofPaulownia Henan Agriculture University. Zhengzhou 450002, P. R. China. Responsible editor: Song Funan     

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.     

Litterfall,litter decomposition and the use of mulch of four indigenous tree species in the Atlantic lowlands of Costa Rica

Litterfall, forest-floor litter biomass and nutrients, short-term litter decomposition and the effects of leaf mulches on initial growth of maize were studied for four indigenous tree species with agroforestry potential:Stryphnodendron microstachyum Poepp. et Endl.(S. excelsum), Vochysia ferruginea Mart,Vochysia guatemalensis Donn. Sm. (V. hondurensis) andHyeronima alchorneoides (O), growing in a young experimental plantation in the Atlantic humid lowlands of Costa Rica. Total annual leaf litterfall was higher inV. ferruginea plots, followed byS. microstachyum, V. guatemalensis andH. alchorneoides; all with values comparable to those reported for other tree species grown in agroforestry combinations in humid tropical regions. Forest-floor litter accumulation was highest underV. ferruginea andV. guatemalensis. Both litterfall and forest-floor litter material had similar patterns in nutrient concentrations: N was higher inS. microstachyum, Ca was higher inV. guatemalensis, K was higher inH. alchorneoides; Mg was higher inV. guatemalensis andH. alchorneoides; H. alchorneoides andV. guatemalensis had the highest P.V. ferruginea litter decomposed more slowly, whileS. microstachyum apparently decomposed faster than the other species. The twoVochysia species showed increases in N and P concentration in decomposing litter after seven weeks in the field,H. alchorneoides showed an increase in litter N and a decrease in litter P, andS. microstachyum showed a net decrease in both N and P over the same time period. The patterns found in the litter bag study were confirmed by results obtained in a tethered-leaves experiment.S. microstachyum andV. ferruginea litters lost more weight when mixed in a 11 proportion than either of them alone. Maize seedlings growing in plots mulched withS. microstachyum andH. alchorneoides leaves showed greatest initial growth, confirming patterns found in decomposition and nutrient release studies. The results show that these species could be used in agroforestry combinations with different advantages according to the specific objectives desired, whether these are soil protection, nutrient recycling, or enhancement of the growth of associated crops.     

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.