退化山地生态系统恢复和重建探析

近年来,人口增长较为迅速,随着需求量的增加,对于自然资源的开发越来越频繁,生态系统已经开始呈现出大规模的变化。人类的日常生活已经严重干扰了自然生态,也热带森林已经受到了不同程度的影响。由于过渡采伐森林资源等,导致生态系统开始出现退化,需要个到各地不各部门的重视。本文主要针对退化山地生态系统恢复以及重建进行分析,为自然生态系统的恢复做出一定的贡献。     

辐射松、油松幼苗抗旱性能比较

采用盆栽控水法和单因素试验设计,对两种针叶树种辐射松(Pinus radiata D.Don)、油松(Pinus tabulaeform is Carr.)幼苗在连续干旱胁迫下分别测定其植株的叶片相对含水量、质膜相对透性、脯氨酸含量和脱落酸含量等4项抗旱生理指标,以评定两种树种的抗旱性能。研究结果表明,在连续干旱胁迫下,两树种叶片相对含水量均呈下降趋势,但辐射松的降幅较大,两树种的质膜相对透性、脯氨酸含量和脱落酸含量均有所增加,但辐射松的增幅较小,因此,辐射松的抗旱性能次于油松。     

化学调控剂在巨尾桉扦插育苗上应用与推广

化学调控剂在巨尾桉组培苗嫩梢扦插育苗上的应用结果表明,化学调控剂能明显延缓或抑制巨尾桉扦插苗高生长,促进地茎生长,在抑制主根生长的同时强烈促进侧根生长。施用1.0 g.m-2的化学调控剂60 d内高生长仅增加3 cm,地茎增长0.12 cm,生根条数达20~30条,出圃率达95%;而不施药的苗木60 d内高生长增加17.6 cm,地茎增长0.05 cm,生根条数仅8~12条,出圃率只有85%。应用化学调控剂能提高苗木质量和产量,起到了贮存苗木作用,使用方法简便,成本低,效果好。     

四川阿坝辐射松引种长期森林健康风险初步评估

Pinus radiata was introduced to the summer rainfall environments of Sichuan Province, China in the 1990s as a part of an afforestation pmgram for soil and water conservation in the arid and semi-arid river valley area of Aba Prefecture. Within this region a total area of 26 000 ha have been identified through climate matching as suitable and a further 63 000 ha potentially suitable for environmental plantings of P. radiata. The plantations are being established in widely separated small patches on steep and degraded slopes along the dry river valley The newly introduced P. radiata are exposed to two kinds of forest health risks： they may be attacked by （a） indigenous pathogens and pests against which they may not possess any resistance or （b） by inadvertently introduced foreign pests or pathogens. This paper presents a survey of the potential damaging pests and a preliminary assessment of forest health risks facing the P. radiata plantations over a much longer timeframe than the initial phase of introduction and early plantation establishment. An empirical appmach was adopted to evaluate forest health risks by a combination of literature review, examination of historical records of pest and disease outbreaks in the surrounding conifemus forests, field surveys and inspections, specimen collection and identification, and most importantly, expert analysis of the likelihood of attack by specific pests and pathogens and the subsequent impact of such attacks. The assessment identified some specific forest health risks to the long-term success of P. radiata introduction in this area. These risks are closely associated with the indigenous pests and pathogens of the two native pine species, P. tabulaeformis and P. armondii since these pests and pathogens are considered more likely to establish on P. radiata over time. Exotic pests and pathogens are of a quarantine concern at present. Based on the results of assessment, recommendations are pmvided to improve forest vigour and to reduce the forest health risks pos     

薄壳山核桃大砧木嫁接技术

薄壳山核桃是世界著名的干果。大砧木嫁接是良种繁育、品种改良、嫁接授粉树的重要技术手段。该文介绍了接穗的采集时期和贮藏,嫁接部位和＂放水＂方法,嫁接时期和嫁接方法,嫁接后的管理等方面的成功技术和经验。     

水稻生产技术的应用价值与实践途径

水稻生产过程中,各类农业技术措施的应用和落地具有突出价值.农业技术措施的有效运用,对提升水稻种植、管理和生产效能具有正向促进作用,要引发足够重视.据此,阐述了水稻生产技术措施的应用背景和应用价值,并重点分析了水稻生产技术措施的应用途径和思路,提出了与之相关的操作建议.     

种公猪睾丸阴囊肿大症的防治

加强种公猪的饲养管理和疾病防治，确保公猪精液质量，可提高母猪受胎率。若公猪发生睾丸阴囊肿大症，会引起体温升高，食欲减退或废绝，精液品质下降，导致母猪受胎率降低。病情严重的公猪将遭到淘汰，造成很大的经济损失。笔者就种公猪睾丸阴囊肿大症的病因及防治浅析如下：１病因分析１．１传染病致睾丸阴囊肿大１．１．１布鲁氏杆菌病：猪一般多为隐性感染。猪感染布鲁氏杆菌后，母猪会发生流产、死胎及娩出体弱的仔猪，流产后可发生子宫炎和不孕症，公猪会发生急性或慢性睾丸炎症、肿大。该病用血清学方法可以确诊。１．１．２放线杆菌…     

降香黄檀引种试验初报

根据降香黄檀生物学和生态学特性及仙游县的生态环境条件对其进行引种试验,初步结果表明,降香黄檀在仙游县四旁和低山(海拔高200m~300m)引种生长表现正常,造林成活率达98%以上,8个月苗高生长量达1.67m;地径达1.86cm,未发现冻害,能安全过冬,对气候适应性强,为在仙游县大力发展该树种提供科学参照。     

干旱地带应用DBOL保水剂营造山杏的试验研究

经过连续三年利用DBOL保水剂对山杏裸根苗造林及幼林生长的试验研究,结果表明：(1)山杏裸根苗造林保存率提高10．5％～14．5％;(2)山杏幼林高生长量增加41．3cm～53．0cm,地径生长量增加1．83mm～2．05mm;(3)山杏幼树提早15天左右萌动,延迟10天左右停止生长;(4)山杏幼树营养生长增强,生殖生长减弱。     

ABT生根粉在巨尾桉和花卉果树扦插育苗上的应用

ABT生根粉在巨尾桉和花卉果树扦插育苗上的应用结果表明 ,ABT生根粉能有效促进巨尾桉和其他花卉果树扦插生根。应用ABT 1号生根粉 5 0 0× 10 -6～ 10 0 0× 10 -6处理插条 ,可提早生根 ,生根率达 95 %以上。应用ABT 2号生根粉10 0× 10 -6～ 2 0 0× 10 -6处理橡皮树等插条 0 5h ,生根率达 90 %～ 98%。应用ABT 3号生根粉处理九里香、天竺桂小苗 ,可提高成活率 10 %～ 15 %。