【摘要】 1999年春季，大连地区约有2000多公顷日本黑松林相继出现不同程度的松枝枯黄，乃至全株枯死现象，调查结果表明：这次灾害是一次气候异常引起的自然灾害，病虫害等不是造成该灾害的主要原因。更多还原

【Abstract】 About 2000hm~2 of Pinus thunbergii became withered and even died in Dalian region during the spring of 1999. The bureau of forestry in Dalian invited some relevant experts to investigate the reason. The results showed that there was the natural calamity caused by weather abnormality. Other thing such as plant diseases and insect damage are not the main reason.更多还原