摘要
通过对巨柏天然分布区的样地调查,并结合实验与长期的观测,研究了巨柏的地理分布、物候特性、繁殖特性和光合特性以及个体生态学和群落学特性。结果表明:(1)巨柏分布范围极其狭窄,个体数量十分有限;(2)巨柏雌雄花期不同步,结实率低,种子千粒重仅为2.70g;(3)巨柏种子活力最高只有39.8%,平均只达到34.6%,室内条件下,种子发芽率较低,平均只达到32.67%,巨柏在自然分布区的条件下,种子萌发困难;(4)巨柏苗木适合在23℃、相对湿度60%左右的条件下生长,巨柏自然分布区的条件不利于苗木生长;(5)自然环境条件下,巨柏光合速率表现为单峰形曲线,能有效积累光合产物,为巨柏在逆境中生长创造了有利条件;(6)巨柏群落科属组成丰富,乔木层树种组成单一,种群结构多为衰退型。种子萌发困难、结实率低、外界干扰是导致巨柏濒危的主要原因。除了对迁地保护进行深入研究,扩大繁殖和栽培外,对巨柏的保护应立足于就地保护。
Cupressus gigantea is a rare species endemic to Tibet. Now it is in endangered condition and have been classified as national first - rate protective plant. The studies on the geographic distribution, phenology, reproduction, photosynthesis, individual ecology and community characteristics of C. gigantea were conducted by plots investigation, experiment, and long field observation of C. gigantea in natural condition. The results showed that： （1） the distributive scope of C. gigantea was very narrow and its quantity was rather limited; （2） the florescence of female flower and male flower＇s were out of step, fruiting rate was low, and thousand seeds weight only 2.70g; （3） the maximum of seeds vigor was 39.5 % and its average percentage was only up to 34.6 %, the germinstion percentage of seeds in laboratory was low, the average of which was only 32.67%, it was diffcult to sprout if the seed was in natural condition; （4） the nursery stock grew well in the condition that temperature was 23°C and relative humidity was about 60 %, but it didn＇t grow well in natural environment conditions ; （5） the diurnal course of photosynthetic rate of C. gigantea showed one single peak in natural environment conditions, which increased the amount of photosynthesis in daily course and made advantage to the growth of C. gigantea; （6） the composition of family and genus was rich in the community of C. gigantea, the composition of species was single in the storey of tree, and the community was on the decline. Low germinatingrate, low fruiting rate, and severe disturbance were the major causes resulting in the endangered situation of C. gigantea. We suggest that the preservation strategies should be centred on in situ conservation, besides ex situ conservation, exoanding propagation and cultivation.
出处
《林业科技》
北大核心
2006年第2期1-5,共5页
Forestry Science & Technology
基金
国家自然科学基金项目(30260020)资助
关键词
巨柏
生物学特性
生态学特性
濒危
保护
Cupressus gigantea
Biological characteristics
Ecological characteristics
Being endangered
Conservation
