论集体林区林地产权制度变迁的路径

林地产权制度改革是实现林业可持续发展的需要。文中在分析集体林区林地产权制度缺陷的基础上,提出了林地产权制度变迁的路径。     

浅谈牛栏江河道绿化的途径及措施

指出了当前牛栏江水污染严重,牛栏江生态廊道绿化的任务是提高河流“自净”能力,净化水质。探讨了绿化技术途径,包括对河岸带进行区划,确定各带（区）的功能,根据各带（区）特点,布置植物,强调在有限的空间内,千方百计地增加湿生与水生植物种植面积,利用水生植物净化水体,从而实现规划目标。     

Fungal inoculation induces agarwood in young Aquilaria malaccensis trees in the nursery

Fungi are often used to induce agarwood inAquilariatrees. This study was conducted to evaluate the effect of several fungi on agarwood formation over time in youngAquilaria malaccensis （Lam.） trees. Typical changes in the length and light intensity of the resulting discoloration were observed after three and six month periods following inoculation. Wood samples were observed microscopically and classified into several light intensity groups. The discoloration length was meas-ured longitudinally. The duration after inoculation affected the mean of discoloration length： the 6-month old sample （1.70 cm） had a wider discoloration zone when compared to the 3-month old sample （1.17 cm）. When measuring the discoloration intensity, a positive relationship with time was perceived. Digital images, captured using a camera-equipped microscope, revealed that wood samples collected after six months appeared to be 1.8-times darker than after three months. We concluded that time, not the species of any of the tested fungi, had significant effect on discoloration length and intensity. Gas chromatography/mass spec-trometry （GCMS） analysis of the 6-month old sample yielded some important agarwood compounds such as benzylacetone, anisylacetone, guaiene and palustrol. This demonstrates that the tested fungi have the ability to induce agarwood formation in nurseryA. malaccensis trees.     

长白落叶松“两行一带”造林模式的合理性研究

边缘效应(Edge effect)的优势已被人们普遍认识。根据边缘效应的原理,运用"两行一带"的造林模式,人工建立长白落叶松4m、8m、12m带效应区,对其水分、土壤温度、土壤元素及生产力情况进行分析,得出结论:8m效应带是最佳选择。原因是它既能保证保留带林木的正常生长,又能为效应带创造优良的生态条件;既符合国家资源调查的有关技术规定,认定为片林,又能使林分达到生态、社会、经济三大效益的最佳结合。     

林区旅游资源产品化研究

林区是旅游资源的富集区,具有发展旅游业的潜力。但是,由于市场观念的缺乏,其资源优势并未转化为产品优势与经济优势,旅游资源产品化成为林区旅游发展的首要任务。本文剖析了旅游资源与旅游产品关系,在分析林区旅游资源产品化的背景及其旅游资源开发的优势与障碍的基础上,提出了林区旅游资源产品化的战略构想与策略。     

元江冬季露地切花唐菖蒲大面积栽培实验研究

１９９５年１０月至１９９６年３月利用云南元江低热河谷气候进行唐菖蒲冬季露地生产性栽培试验，证明具有开花早，花色好，新母球发育健壮以及投资成本低等优点，具有较好发展前景。     

Planted conifer seedling growth under two soil thermal regimes in high-elevation forest openings in interior British Columbia

A field trial was conducted investigating the single season growth response of 1+0 313 PSB Engelmann spruce (Picea engelmannii Parry ex Engelm.) and lodgepole pine (Pinus contorta Dougl. ex Loud.) seedlings planted into two different soil thermal regimes at three high-elevation locations spanning 200 km in the Engelmann Spruce-Subalpine Fir (ESSF) biogeoclimatic zone in the Cariboo Mountains of central British Columbia. Temperature treatments represented the extremes of soil temperature commonly found in high-elevation clear-cuts. A warm soil treatment (clear day, mid-afternoon soil temperature in mid-summer of 18 to 25 °C at –10 cm) consisting of a bare mineral soil hummock (average dimensions of 100 cm × 100 cm × 40 cm) was contrasted with a cool soil treatment (clear day, mid-afternoon soil temperature in mid-summer of 10 to 13 °C at –10 cm) comprised of organic forest floor overlying mineral soil. By the end of the growing season, seedlings of both species planted into the warm treatment generally exhibited greater root, stem, foliage, and total seedling biomass than cool treatment seedlings. Measurements of root growth at 30, 60, and 90 days after planting showed that total root number and total root length were consistently greater for warm treatment seedlings than for cool treatment seedlings. Root growth was greater from the bottom rather than from the side of the root plug for all seedlings. These results suggest that the effect of low soil temperatures on outplanted styroblock conifer seedlings is pronounced and may be limiting growth performance in high-elevation plantations in British Columbia. We recommend silvicultural treatments that secure natural regeneration, ensure that warmer microsites are always planted, and utilize seedling stocktypes able to make rapid lateral root growth into warmer surface organic horizons.     

潮间带沉积物中重金属污染评价及生物有效性研究进展

潮间带是一个典型的环境脆弱带和敏感带,极易受到人类活动的破坏.潮间带重金属除了直接对潮间带生物有影响外,还可以通过过食物链的富集和放大作用影响人类健康,同时由于潮间带水动力和生物活动的影响,造成重金属的重新分布和释放,产生重金属的"二次污染",直接危害近岸环境.开展重金属元素在潮间带沉积物中含量、赋存形态、污染评价及其生物有效性已成为目前环境科学领域中十分重要的研究内容和任务,国内外学者均对河流沉积物重金属污染开展了大量的研究.文章从这4个方面阐述了潮间带沉积物重金属研究进展,以期为潮间带沉积物重金属研究提供一定的参考.     

景洪市沧江新区生态植被恢复中的树种选择与配置

依据实地调查分析,按适地适树、选树适地等树种选择原则,从树种的生物学特性和景观功能出发,选择了望天树、榕树、羊蹄甲、菩提树、黄竹等30多个主要树种及备选树种作为景洪市沧江新区生态植被恢复树种,并拟定了黄竹纯林型、望天树＋干果榄仁＋番龙眼混交型等11个树种配置模式．     

Ophiostomatoid fungi associated with bark beetles onAbies veitchii in wave-regenerated forests

Relationships between tree mortality and bark beetle infestation onAbies veitchii at the wave-regenerated forest in Mt. Asahi, Okuchichibu area were investigated. Most of the firs with green needles and newly developed current year’s shoots in the dieback zone were heavily infested by bark beetles before the death of the trees. After heavy infestation of beetles, about half of the infested firs died within the year, and the other half died in the next year. When the species composition of bark beetles and associated ophiostomatoid fungi were investigated in Mt. Asahi and also at a typical wave-regenerated forest in Mt. Shimagare, Yatsugatake area,Cryphalus montanus andC. piceae were dominant beetle species for Mt. Asahi and Mt. Shimagare, respectively.Ophiostoma subalpinum andO. europhioides were dominant fungal species at both wave-generated forests. BecauseO. subalpinum was detected more frequently from deeper areas of sapwood thanO. europhioides, it was suggested that the fungal species may accelerate the death of stressed firs in wave-regenerated forests. Contribution No. 169, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba.