荒漠化土壤对人工植被恢复工程的响应

人工植被恢复是荒漠化土壤逆转的主要途径,通过对青海省沙珠玉治沙站人工植被恢复工程下荒漠化土壤逆转过程中土体构型、土壤质地、元素组成和理化性质的分析,研究了荒漠化土壤对人工植被恢复工程的响应.结果表明,人工植被恢复工程对荒漠化土壤具有很好的改良作用,受人工植被影响,土体构型逐渐复杂,出露地表的母质层逐渐被淋溶层和淀积层覆...     

人工辅助措施对文冠果坐果率的影响

通过采取不同的人工辅助措施进行了提高文冠果坐果率的试验,结果表明：人工辅助措施中,以液体喷雾提高坐果率效果最为显著,坐果率达到4.12%。喷施植物生长调节剂中,以50 mg L-1的赤霉素处理,提高坐果率效果最显著,达到5.47%;其次为2000 mg L-1的丁酰肼处理水平,为4.95%;再次为1000 mg L-1的青鲜素处理水平,达到4.89%。     

白马鸡人工驯养初步研究

通过人工饲养的方式探索出白马鸡驯养的经验,即:在野生白马鸡适宜生境下建立饲养场,从育雏阶段开始进行人工投食饲养和本地土鸡带领相结合的驯养方式。目前已经完成从子一代到子二代的完整驯养、饲养流程,取得了云南省林业厅的驯养繁殖许可证。对育雏、亚成体、成体阶段的喂食量、存活情况等作了分析,认为接近原始生境的环境及本地带雏母鸡是成功的重要条件。     

Summarization on Evaluation of Ecological Value of Artificial Forest

INTRODUCTIONBecause of the interleaving, extensity of multi-factorsaffecting forest ecological benefit in space, and thecomplexity of bio-factors of forest,and in themeantime, because of lacking of consultation forthe transformation between physical and ecologicalquantum and monetary value, the evaluation ofecological benefit of forest is all along one of thedifficult problems in academic field. In recent years,some scholars have made much research andexploration in the theory and practice…     

次生阔叶林改建为食用菌原料林后的群落恢复和林分生长

选择12年生林相较好的天然次生阔叶林,通过择伐更新和皆伐人促更新2种经营方式定向培育食用菌原料林。研究发现,择伐经营的经济效益较高,且有利于群落的快速恢复,经过7a的封育,林分蓄积量已达到择伐前的水平。皆伐人促更新获得的食用菌材虽较择伐利用高出40%左右,但因经营强度过大,保留的幼树受损严重而不利于伐后林木的生长与恢复,封育期内蓄积增长量分别为择伐更新和对照未经营区的64 7%和73 41%。动态监测结果显示,采用择伐和皆伐人促更新措施后群落恢复较快。疏伐后因透光度的急剧增加,阳性和中性树种大量侵入,地面芽植物和1年生植物的比例增高。到第7a时,高位芽植物的比例已接近未经营区的状态,乔、灌、草各层的物种多样性指数高于未经营的天然阔叶林,物种均匀度则与其相近。研究还发现,2种更新经营方式对土壤养分的损失较小,经过7a的恢复,林地土壤肥力已基本达到原有天然林水平。     

纤维素废料与造纸黑液木质素制人造木材之探讨

介绍了现有人造木材的种类，阐述了用竹刨花、竹（木）屑等竹（木）加工剩余物或农作物秸秆与造纸黑液中提取的木质素开发人造木材的重大意义，简要介绍了该人造木材的制造原理和方法以及产品的用途，并分析了人造木材的市场前景及其产业化的可行性。     

濒危植物沙冬青人工种群建立技术

建立人工种群是保护荒漠珍惜濒危植物沙冬青、扩大沙冬青种质资源、建立种质基因库的根本途径。播种苗移植造林和直播造林是建立沙冬青人工种群的2种途径。在干旱沙区，如何提高移栽成活率是沙冬青移植造林中最大的技术难题，而直播造林往往受到土壤水分条件的限制。试验从两条途径入手，通过田间对比试验，探试了不同浓度的ABT生根粉(3号)、苗木截体处理和苗龄对沙冬青苗木移植成活率及其生长状况的影响，试验总结了在年降水量小于150mm的干旱沙区进行沙冬青大田育苗的各个技术环节，同时对沙冬青直播造林中种子处理、馅播技术和人工种群的抚育管理也进行了一定的试验和探讨。     

天童林场杉木人工林间伐后林下植物结构特征的研究

对种植26a的天童林场杉木人工林林下植物的群落结构进行了初步的调查研究。结果表明，杉木人工林林下共有植物59种，主要包括樟科、壳斗科、山茶科等．其中分布最多的树种是红楠、栲树、薄叶润楠、细枝柃、南酸枣、枫香、细叶青冈、赤皮青冈、山杜英等；大多数林下植物的高度在2．0～2．5m，有10．6％的植株高度在3．5～4．0m，大于6m的植株数量约占全部的6．8％。林下常绿树种的胸径多在1．0—3．5cm，落叶树种南酸枣和枫香的平均胸径较大，分别为3．6和6．2cm。     

Evidence of cormorant‐induced mortality,disparate migration strategies and repeatable circadian rhythm in the endangered North Sea houting (Coregonus oxyrinchus): A telemetry study mapping the postspawning migration

Life history theory predicts a trade‐off between migration and residency where migration is favoured when it infers elevated fitness. Although migration to more favourable environments may offer higher growth rates, migrants often experience increased mortality due to predation. Here, we investigated mortality and migration behaviour of the North Sea houting (Coregonus oxyrinchus), an anadromous salmonid endemic to the Wadden Sea. We used acoustic telemetry to map the migration of the only remaining indigenous population by applying stationary hydrophones combined with manual tracking. Data suggested a total mortality of 26%, with 30% of the total mortality attributed to predation by great cormorants (Phalacrocorax carbo sinensis), highlighting that North Sea houting conservation could be jeopardised by increased cormorant predation. Risk of cormorant predation was size‐dependent, with smaller fish suffering higher risk of predation. The study found North Sea houting to exhibit disparate migration strategies and identified a lentic area in the estuary as an important habitat. Two newly established artificial lakes within the river system significantly reduced the migration speeds, possibly indicating constrained navigation through the lakes. The migration into the Wadden Sea correlated with temperature perhaps indicating osmoregulatory constraints of sea entry. Unlike many salmonid species, migration occurred both day and night. Moreover, fish exhibited repeatable individual differences in diel activity patterns, suggesting that individuals differ consistently in their migratory activity throughout the 24‐hr period. Our study provides novel information on salmonid migration, which is crucial for the development of science‐based conservation strategies.     

The influence of environmental factors on the upstream movements of rheophilic cyprinids according to their position in a river basin

Throughout their lives, fish accomplish frequent movements between functional habitats that are often triggered by environmental signals. We aimed to determine if rheophilic cyprinids (barbel, Barbus barbus and chub Squalius cephalus), living in different places of the same river basin, may develop similar movement periodicities and react identically to environmental cues to carry out their spawning migration. We used the capture data of three modern fish passes that were monitored continuously during three consecutive years (2010 to 2012) in three rivers of the Meuse basin in Belgium. We captured 418 individuals at adult stage, and the capture number per species was greater (80%) in spring (during the spawning migration period). The spawning migration of the barbel occurred earlier (median = 122nd day of the year) and at lower temperatures (median = 14.5°C) in the lowland rivers compared to the upland river (140th day of the year and 18.4°C). For the barbel, migration initiation differed depending on the river but finished under similar environmental conditions. In contrast, for the chub, no significant difference between rivers was observed regarding spawning migration periodicity and environmental cues. Within the same river basin, rheophilic cyprinids demonstrate flexibility in their responses to environmental variables and may optimise the start date of migration to spawning grounds depending on their local environment and individual experiences. This phenomenon was more pronounced in the barbel, which has more specific ecological requirements.