CAJ | 학술논문

2008年8月,采用典型取样法,设置20 m×30 m(或15 m×30 m)的方形样地13个,对广东省天井山林场杉木(Cunninghamia lanceolata)人工林冰雪灾害进行调查.结果表明:1)粤北地区杉木人工林受损严重,样地内受害杉木比例高于80%,主要集中在海拔500-900 m的地区;2)杉木人工林受损类型主要划分为3种,以折断类型为主(65.09%),其次为倒伏(或翻蔸,18.37%)和弯曲(3.20%).其中,根据不同程度将折断划分为5个级别:轻微受损,即断稍(占折断总数的12.28%);轻度受损,即树冠顶端至中部断裂(38.49%);中度受损,即树冠中部至下部断裂,受到较严重损伤(31.15%);严重受损,即树冠全部受损(15.97%);极严重受损,即树冠近根部断裂或折断后枯死(2.11%),树冠受损为杉木受灾的主要特征;3)林分密度过高(>3 500株·hm~(-2))或过低(<1500株·hm~(-2))都易造成杉木折断,坡向与坡位对其影响较小,合理的密度调控至关重要;4)杉木胸径对受损类型及程度的敏感性较高,表现为粗壮杉木易发生断稍和较轻微的树冠受损,细弱杉木虽不易折断,但一经折断则受损严重.适宜的尖削度对有效预防和减轻杉木受损十分重要.
2008년8월,채용전형취양법,설치20 m×30 m(혹15 m×30 m)적방형양지13개,대광동성천정산림장삼목(Cunninghamia lanceolata)인공림빙설재해진행조사.결과표명:1)월북지구삼목인공림수손엄중,양지내수해삼목비례고우80%,주요집중재해발500-900 m적지구;2)삼목인공림수손류형주요화분위3충,이절단류형위주(65.09%),기차위도복(혹번두,18.37%)화만곡(3.20%).기중,근거불동정도장절단화분위5개급별:경미수손,즉단초(점절단총수적12.28%);경도수손,즉수관정단지중부단렬(38.49%);중도수손,즉수관중부지하부단렬,수도교엄중손상(31.15%);엄중수손,즉수관전부수손(15.97%);겁엄중수손,즉수관근근부단렬혹절단후고사(2.11%),수관수손위삼목수재적주요특정;3)림분밀도과고(>3 500주·hm~(-2))혹과저(<1500주·hm~(-2))도역조성삼목절단,파향여파위대기영향교소,합리적밀도조공지관중요;4)삼목흉경대수손류형급정도적민감성교고,표현위조장삼목역발생단초화교경미적수관수손,세약삼목수불역절단,단일경절단칙수손엄중.괄의적첨삭도대유효예방화감경삼목수손십분중요.
Aims Forest ecosystems were seriously damaged by unusually heavy snow and ice in early 2008 in southern China. Chinese fir (Cunninghamia lanceolata), the main timber tree in southern China, was one of the most se-verely affected species. Our objective was to investigate and assess types and extent of damage to this tree species in plantation stands in northern Guangdong, analyze relationships among site condition, forest structure and dam-age, and provide a theoretical basis and technical guidance for protecting existing forest resources and restoring damaged forests.Methods The study was conducted in Chinese fir plantation in Tianjingshan forest farm of Guangdong, which was damaged by this snow and ice event. Thirteen plots 20 m × 30 m (or 15 m × 30 m)were placed in typical damaged areas in August 2008. Site factors such as altitude, aspect, slope position and slope steepness were re-corded, and forest structure factors such as trunk diameter at breast height (DBH), tree height, crown size, lowest height of living branches, trunk taper (diameter/height)and stand density were measured. Important findings Over 80% of the Chinese fir trees at 500-900 m elevation were damaged. There were three types of damage: crown broken (65.09%), uprooted (18.37%)and trunk bent (3.20%). The crown broken category was divided into five grades corresponding to extent of damage: top broken, crown fracture from the top to the central part, crown fracture from the top to the lower part with serious injury, entire crown broken, trunk broken off near the base or tree death after trunk broken. Plantation density was very important for the resistance of Chi-nese fir to the snow and ice storms, because trees were more severely broken where stand density was > 3 500 per hm~2 or < 1500 per hm~2. DBH was a sensitive index of the type and extent of damage. Stunted trees tended to show mild damage. Trunk taper was an important factor for Chinese fir in the prevention and mitigation of snow and ice damage.