Management of pine wilt disease in Korea through preventative silvicultural control   总被引：3，自引：0，他引：3  

Tae-Sung KwonJoon Hwan Shin  Jong-Hwan LimYoung-Kul Kim  Eun Ju Lee 《Forest Ecology and Management》2011,261(3):562-569

Pine wilt disease (PWD) represents a major threat to forest ecosystems worldwide. Although PWD is now better understood, effective control measures for this disease have still not been devised. Here, we report several years of field studies on preventative silvicultural control of PWD. Silvicultural control through preventative clear-cutting and the manual removal of logs was implemented between 2005 and 2009 in 16 Korean districts that had newly PWD-infected stands. Preventative clear-cutting of neighboring asymptomatic pine trees (within a 10-50-m radius of wilt trees) and the removal of felled logs or branches suppressed spread of PWD. Occurrences of PWD wilt pines in districts (city or county) subjected to this silvicultural control method were significantly reduced compared with those in districts using conventional controls (physical or chemical treatment of wilt pine trees). Through silvicultural control, PWD was successfully suppressed in 11 of 16 districts investigated. In contrast, successful control was achieved in only 1 among 18 districts subjected to conventional control. Our results will be of considerable interest to those engaged in the very difficult battle against the global spread of PWD.  相似文献   

泰顺县松类纯林改造技术研究     

林安惠 《华东森林经理》2011,25(3):20-24

通过套种造林、封山育林、抚育改造等措施,将马尾松纯林改造成针阔混交林,以改变树种结构单一、地力日益衰退、病虫害逐年严重、林地灌木杂草丛生、火灾频繁发生、林分产量低下等状况。结果表明：在松林下套种阔叶树,可不同程度增加单位面积阔叶树数量,形成明显的层次结构,能充分利用林地中的营养空间,马尾松和阀叶树在各自不同层次生长范围...  相似文献   

红松针锈病病原菌种与专化型的研究     

潘学仁  隋超 《东北林业大学学报》1993,21(6):31-38

１９８９年到１９９１年，于黑龙江省勃力县通天一林场，通过人工接种和野外观察，孢子形态大小比较，参考有关研究文献，把引起红松针锈病病原的鞘锈菌，看做为由若干个寄生性不同的专化型组成的集成合种是较妥当的方案。按国际命名先后法规，用凤毛菊鞘锈菌作为集合种，分布在中国东北已明确了３个专化型：Ｃ．ｓａｕｓｓｕｒｅａｅ Ｔｈｕｅｍｅｎ ｆ． ｓｐ． ｓａｕｓｓｕｒｅａｅ，Ｃ．ｓａｕｓｓｕｒｅａｅ Ｔｈｕｅｍｅ  相似文献   

阔叶红松林及其次生杨桦林优势树种间氮素营养关系的研究   总被引：2，自引：3，他引：2  

李玉文  李英 《东北林业大学学报》1994,22(1):7-16

为了探讨阔叶红松林演替与原始阔叶红松林稳定性中存在的Ｎ素机制作用，１９９１年７月，在长白山（北坡）自然保护区（海拔７４０ｍ），应用近几年建立的化学和生物化学分析方法，通过分析土壤Ｎ素及有效形态ＮＯ３－Ｎ、ＮＨ４－Ｎ的供应和林木的Ｎ素吸收利用状况，对原始阔叶红松林及破坏后形成的两个不同龄级的杨桦林中优热树种林木的Ｎ素营养状况及树种间Ｎ素营养关系进行了研究。结果表明：１．各样地土壤中Ｎ素营养状况及树种  相似文献   

应用粉拟青霉防治松毛虫   总被引：8，自引：1，他引：8  

武觐文 《安徽农业大学学报》1996,23(3):438-445

本文概述粉拟青霉的形态,生长习性,遗传变异等性状,该菌剂生产,使用方法和安全性以及防治害虫效果,说明粉拟青霉是一种性能良好的杀虫微生物资源,值得开发和推广应用。  相似文献   

中国松针锈病病原菌—鞘锈菌研究现状及问题   总被引：2，自引：3，他引：2  

潘学仁  薛煜 《东北林业大学学报》1991,19(5):84-94

中国松针锈病病原菌——鞘锈菌(Coleosporium Le′v.) 已知有48种,除一种短循环型生活史的偃松鞘锈菌(C.pini-pumilae Azb.)外,其余均为长循环型生活史,夏孢子、冬孢子寄主涉及到单子叶和双子叶植物的13个科,57个属。中国鞘锈菌只有9个种的寄主关系和生活史已明确,其余都未经过人工接种,锈孢子寄主关系及生活史未知。由于鞘锈菌对寄主选择不太严格,相近种的寄主又有重叠,使人们对鞘锈菌按形态定属名,按寄主定种的传统分类方法是否完全合理产生了怀疑。我们认为确定鞘锈菌种,不仅要考虑孢子形态等特征,还要考虑不同地区鞘锈菌对寄主范围,从优选择和限定选择等多种情况,通过人工接种试验,结合野外调查,对鞘锈菌进行深入的研究,扭转当今分类上的混乱局面,为综合防治提供理论依据。  相似文献   

Carbohydrate dynamics in particle-size fractions of sandy spodosols following forest conversion to maize cropping     

C. Jolivet  D.A. Angers  F. Andreux 《Soil biology & biochemistry》2006,38(9):2834-2842

In southwest France, much of the forested land on sandy spodosols has been converted to continuous maize cropping in the last few decades. To evaluate the impacts of this change on soil organic matter properties, we compared total organic C and neutral and amino sugars content in whole soil and particle size separates of two forested, and five related sites that had been either clear-cut for 12 and 18 mo, or cultivated to maize for 4-22 yr. Soil carbohydrates accounted for 4-7% of the total organic C across all sites. Soil organic C contents of clear-cut and cultivated sites were only 57-79% of the average value measured in forested sites. Accordingly, carbohydrate content of clear-cut and cultivated sites were only 35-66% of the value in forested sites. Ordering the sites in a chronosequence indicated that both total organic C and carbohydrate contents decreased with an increase in time elapsed since clear-cutting and maize cultivation. The only exception was a partial recovery of carbohydrate content in the site that had been under continuous maize for 22 yr. The clay+silt fraction (0-50 μm) was enriched in carbohydrates, mainly of microbial origin, whereas the sand size fractions (50-200 and 200-2000 μm) contained fewer carbohydrates which were mainly of plant origin. Monosaccharide analysis of particle size separates revealed significant differences in carbohydrate composition between sites. Relative to forested sites, the coarse and fine sand fractions in clear-cut and cultivated sites were depleted in carbohydrates and were relatively enriched in plant-derived carbohydrates. Carbohydrate content of the clay+silt fraction drastically decreased upon clear-cutting. Amino sugar content was consistently lower in clear-cut and cultivated sites than in forested sites, indicating that microbial populations were negatively affected by clear-cutting and cultivation. The fungal population appeared more sensitive than bacteria to these land-use changes as indicated by a greater decline in glucosamine than in muramic acid contents.  相似文献   

Nutrient cycling in a Pinus patula plantation in the Mpumalanga Province, South Africa     

Joanna F. Dames  Mary C. Scholes  C. J. Straker 《Applied soil ecology》2002,20(3):211-226

The accumulation of litter on the forest floor was identified as a potential problem in managed plantations of Pinus patula (Schlechtd. et Cham.) in the Mpumalanga Province of South Africa in the late 1980s. Litter accumulation in pine plantations is regarded as a threat to site productivity as organic acids are released, moisture penetration is altered and nutrients are immobilised within the litter. This study examines the cycling of nutrients in a 42-year-old P. patula stand in which litter has accumulated. Samples of the vegetation, litter and soil components were collected and chemically analysed for total nitrogen (N), phosphorus (P) and the major cations potassium (K⁺), calcium (Ca²⁺) and magnesium (Mg²⁺). Complete nutrient budgets for N and P, and the cation pool sizes were determined. It was evident from these studies that large reserves of N (1442 kg ha⁻¹) and P (103 kg ha⁻¹) are stored in the litter layers, with levels of cations being low. The presence of large nutrient reserves within the litter and the predominance of fine feeder roots distributed within this layer indicated that a tightly closed plant–litter–plant nutrient cycle was in operation for the cycling of N and P. This may not be true for the major cations. Management of the litter should ensure retention of as many nutrients as possible in the system. This could be achieved through controlled burning to reduce nutrient loss through volatilisation; increasing forest floor temperatures by altering the planting density and application of dolomitic lime to replace cations and to alleviate the acidic conditions making the litter more favourable for decomposing organisms.  相似文献   

马尾松SGW高白度全无氯漂白研究     

胡可信  曾光明 《湖南农业大学学报(自然科学版)》2003,30(6)

对马尾松磨石磨木浆(SGW)进行了单段H2O2漂白和2段H2O2漂白试验，研究了不同预处理方法和条件对H2O2漂白效果的影响，提出了最佳的预处理工艺；同时还研究了以EDTA和MgSO4作为金属螯合剂改善H2O2漂白效果，进而确定了H2O2漂白的最佳工艺参数．结果表明，应用EDTA和MgSO4作为金属螯合剂，SGW经预处理后，采用两段H2O2漂白，漂后纸浆白度可由原浆的47．8％提高到74．5％，从而使制得的漂白浆能满足低定量高白度胶印新闻纸和其他高级纸种的生产要求．结果还表明，与传统CEH3段漂白相比，漂白废水中的CODCr减少78．5％，BOD5减少97％，且不再含有可吸附的有机卤化物(AOX)．  相似文献   

低效马尾松水保林林下植被及生态功能恢复研究Ⅱ恢复成效的分析与评价     

佘济云  曾思齐  陈彩虹 《中南林业调查规划》2002,21(3):1-3

对湖南省茶陵县低效马尾松水保林林下植被及生态功能恢复技术试验及其技术模式研究 ,通过 5a的定位观测 ,试验林的林下植被及生态功能均较对照林分有大幅度的增长  相似文献