Diversity of polyporous fungi (Polyporaceae) in northern boreal forests: effects of forest site type and logging intensity

The effects of forest site type and logging intensity on polyporous fungi were studied in subxeric, mesic and herb-rich forests and spruce mires in northern Finland. The species richness of polypores did not follow the fertility gradient of the site types, but was connected with the amount and diversity of coarse woody debris (CWD). The total number of species, and the numbers of indicator and threatened species were equal in subxeric pine forests and in more fertile spruce-dominated stands. The species composition of pine-dominated forests differed conspicuously from that of spruce-dominated site types. The total number of species was not affected by logging intensity, but no virgin forest species or threatened species were found on the sites where the number of cut stumps exceeded 150 stumps ha^?1. Increasing logging intensity decreased the number of polypore observations, indicating reduced substrate availability. The results stress the importance of protecting not only fertile spruce-dominated stands, but also poorer, pine-dominated forests, and sites with high and diverse CWD content.     

Effects of management on coarse woody debris volume and composition in boreal forests in northern Sweden

Forest management practices have led to a reduction in the volume and a change in the composition of coarse woody debris (CWD) in many forest types. This study compared CWD volume and composition in reserves and two types of managed forest in the central boreal zone of Sweden. Ten areas were surveyed, each containing clear-cut, mature managed and old-growth stands, to determine the volume of standing and lying CWD in terms of species composition, decay class and size class. Volumes of CWD on clear-cuts and in mature managed forests were high compared with previous studies. Old-growth forests (72.6 m³ ha^?1) contained a greater volume of CWD than mature managed forests (23.3 m³ ha^?1) and clear-cuts (13.6 m³ ha^?1). Differences were greatest for the larger size classes and intermediate decay stages. Despite stand ages being up to 144 years, CWD volume and composition in managed forests was more similar to clear-cuts than to old-growth forests.     

宾川县退耕还林地病虫害发生现状及综合防治对策

通过调查分析表明,宾川县退耕还林工程造林成效难以达到预期目标,林农经济收益较低,究其原因之一是森林病虫危害,特别是地下害虫的危害.分析病虫危害发生的自然及人为因素,提出退耕还林工程中加强病虫防治工作,建立无检疫对象苗圃,强化营造林技术措施,加强森防队伍建设,严格检疫,强化抚育管理,优化退耕还林林分、树科结构,搞好工程区病虫害的监测预报工作等综合防治对策.     

青阳县杉木速生丰产林营林技术与成效分析

本文以青阳县木镇镇南河村2004年营造杉木示范林为例,分析杉木速生丰产用材林营林技术措施对林分质量和木材产量的影响。结果表明：示范点林分通过采取细致整地、良种壮苗、认真栽植、精心管护等集约经营措施,比同等立地条件对照造林林分的平均高、平均地（胸）径、林木蓄积量均有明显提高,效益明显。     

Occurrence and berry production of Rubus chamaemorus L., Vaccinium oxycoccus L. & Vaccinium microcarpum Turcz. and Vaccinium vitis‐idaea L. on Swedish peatlands

During three consecutive years, 1978–1980, cloudberries (Rubus chamaemorus L.), cranberries (Vaccinium oxycoccus L. & Vaccinium microcarpum Turcz.) and lingonberries Vaccinium vitis‐idaea L.) growing wild in Swedish forests and mires were inventoried in the annual National Forest Survey. Both the coverage and fertility of these were estimated. Observations from 42 000 test sites (314 m² each) were processed according to geographical region, composition of tree and field layer, altitude and occurrence of draining ditches. Cloudberries cover 425 000 hectares or 1.5 % of the total investigated area (28.6 million hectares). The corresponding values for cranberries and lingonberries are 136000 hectares (0.5 %) and 1362000 ha (4.8%) respectively. Open mires have a greater degree of coverage by cloudberry and cranberry than wet forests on peat. The reverse situation is true for lingonberry. The total berry yield on peatland was estimated to 116.6 million kg (freshweight), distributed as 75.7 million kg cloudberries, 20.8 million kg cranberries and 20.1 million kg lingonberries. The corresponding production of lingonberries on mineral soils was 188.8 million kg. Both in wet forests and on mires, drained areas show lower berry production for the three species, with one exception. Lingonberries yielded better on drained mires. Productive stands of cloudberries and cranberries ought not to be drained for economic reasons.     

毛竹低产低效林的经营策略研究

毛竹是南方竹产区山区农户主要经济收入来源和当地农业经济的支柱产业之一.当前,毛竹低产低效林面积依然很大,占竹林总面积的60％左右.该文以农户访谈和二手资料收集等方法,了解掌握毛竹低产低效林改造的技术状况和运行机制,从毛竹培育技术、农户对技术采用和扩散的特征分析出发,提出了毛竹低产低效林的经营策略建议.     

油茶无性系及自然林选优调查分析

在江西省6个县进行油茶无性系及自然林选优调查分析,结果表明,长林、赣无、赣州油系列无性系优树整体表现出较好的经济性状,主要表现为鲜果含油率、平均冠幅产果量及产油量较高,高产优树较多,自然林优树整体表现低于无性系优树,但存在一部分表现高产的优树,无性系优树间、不同地区自然林优树间、同一地区自然林优树间经济性状差异较大,这为油茶选优工作提供了参考依据和空间。今后油茶选优宜重点从现行推广的无性系中进行优中选优,结合在自然林中进行一定的选择,以达到节约成本、提高效率的目标。     

香椿材用林丰产栽培试验初报

本文开展了香椿材用林不同品种、密度与施肥量的栽培试验。研究结果表明:香椿造林第二年以九江种源地径增长最快,年均达2.016 cm;而树高增长以中密度2 m×2 m最大,年均增长0.606 m;复合肥株施0.75 kg对香椿后期地径、树高与冠幅增长效果最佳。提出江西省香椿材用林培育采用九江种源、初植密度2 m×1.5 m与株施0.75 kg复合肥有利于幼林生长。研究结果可为江西省香椿材用林培育提供科学依据。     

油茶不同地理起源自然林的优树产量与干籽含油率分析

调查在江西6个县油茶自然林分中初步选择的单株优树的产量及其干籽含油率,比较分析不同地理起源的油茶优树产量与干籽含油率差异。结果表明:油茶自然林分优树存在地理种源上引起的干籽含油率与产量差异,且差异显著,抚育管理对油茶自然林的产量可产生明显效果;而对青黄果色的油茶产量影响不明显,但对干籽含油率差异显著。