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20世纪90年代,在实施水土保持造林项目的过程中,辐射松被引种到四川阿坝干旱河谷地区。气候匹配研究显示该区域有26000公顷土地适宜辐射松生长,另外还有63000公顷土地也可能具备种植辐射松水土保持林的环境条件。该区域的辐射松人工林以小片林的形式分散在干旱河谷沿岸陡峭和退化的坡地上。这些引种的辐射松面临两种森林健康风险:(a)它们可能不具备抵御当地原有的病原和昆虫侵害的能力,(b)也可能受到外来有害生物入侵的威胁。本文对可能威胁辐射松的潜在的有害生物进行了调查分析,并对其所面临的长期森林健康风险进行了初步评估。评估方法结合了文献研究、周边针叶林病虫害发生历史记录、野外调查、标本采集鉴定,对主要有害昆虫和病原侵袭的可能性以及侵害发生后将造成的影响进行了专家分析。结果表明该地区辐射松引种成功面临着一些特定的长期健康风险。这些风险和侵害两种乡土树种――油松和华山松的有害生物密切相关。因为这些昆虫和病原菌随着时间的推移很可能会传给并危害辐射松。对辐射松引种有潜在威胁的外来有害生物应列为检疫对象。根据评估结果,本文提出了增强森林生长活力和降低健康风险的建议。文中也提到了一旦有害生物侵入并构成危害时,如何提高控制森林健康风险的能力。尽管这些森林健康风险对辐射松生长是有害的,但尚不能对辐射松引种成功构成严重影响。
In the 1990s, during the implementation of soil and water conservation afforestation project, Pinus radiata was introduced into the dry valley of Aba in Sichuan Province. Climate match studies have shown that 26,000 hectares of land are suitable for the growth of radiata pine in this area and an additional 63,000 hectares of land may also have the environmental conditions for planting Pinus tabulaeformis forests. Pinus radiata plantations in the area are scattered in the form of patches of forest on steep and degraded slopes along the arid valley. These introduced radiata pine are faced with two forest health risks: (a) They may not have the ability to withstand the indigenous pathogens and insects present in the area, and (b) may also be at risk of invasive alien pests. This paper investigates and analyzes potential pests that may threaten Pinus radiatus and provides a preliminary assessment of the long-term health risks they face. The assessment method combines literature review, history of coniferous forest pests and diseases occurrence, field investigation, specimen collection and identification, the possibility of invasion of major harmful insects and pathogens, and the impact that will be caused after the invasion. The results show that the successful introduction of Pinus radiata in the region faces some specific long-term health risks. These risks are closely linked to the pests that attack two native species, Pinus tabulaeformis and Pinus armandii. Because these insects and pathogens are likely to pass on and endanger radiobacteria over time. Exotic pests that pose potential threats to the introduction of Pinus radiata should be classified as quarantine targets. Based on the results of the assessment, this paper presents recommendations for enhancing the viability of forests and reducing health risks. The article also mentions how to increase the ability to control the health risks of forests once the pests invade and pose a hazard. Although these forest health risks are detrimental to the growth of Pinus radiata, they do not yet have a significant impact on the success of Pinus radiata.