摘要
先锋生态系统的小气候效应是评价它们在植被生态恢复过程中恢复效能的主要指标之一。对 1 4龄的马占相思 ( Acacia mangium)、荷木 ( Schima superba)、湿地松 ( Pinus elliotii)人工林小气候效应的对比研究表明 ,荷木林的降温保湿效应最好。气温 (最高温、最低温和平均温 )和土壤温度 (地表最高温、最低温和平均温度 )均为 3种林分中最低。荷木林林内气温一般比马占相思林和湿地松林低 0 .1～ 0 .5℃ ,地表和土壤温度一般低 0 .3～ 2 .5℃ ,相对湿度高 1 .2 %。对荷木林和湿地松林温、湿度垂直方向上 4个层次 (距地0 .5 m,2 .0 m,4.0 /5 .0 m,9.0 m)上的观测结果表明 ,湿季林内温度随高度增加而增加 ;在最冷月 ( 1月份 )时 ,林内温度随高度增加而减小。无论是干季还是湿季 ,林内湿度都随林分高度的增加而减小。结合林分结构调查、森林土壤养分含量等资料 ,初步认为 ,南亚热带地带性森林植被人工恢复实践中 ,荷木等本地树种更为适宜。
Regulation of microclimate is one of the major functions of forest ecosystems. After establishment of pioneer forest ecosystems to restore the regional primary forest vegetation, the function of pioneer ecosystems needs to be monitored in order to assess the successfulness of the restoration projects. Microclimate regulating capability is among the important facets of the assessment. Different types of pioneer forests were established in the abandoned subtropical grass slope of Heshan of Guangdong province in order to restore subtropical evergreen broad-leaf forest. Three forest ecosystems established in 1984 were chosen for this study. Our goal was to assess the performance of the three plantations in terms of regulating microclimate, and discuss which one should be planted as the best pioneer community in restoring the primary forest vegetation of the region. Three sets of air and soil thermometers were installed in the three forests in 1997. Sensors of air thermometers were 1.5 m above the surface. Soil thermometers were located at the depth of 0 cm, 5 cm, 10 cm, 15 cm, and 20 cm. Dry and wet ball air temperatures (average, minimum, and maximum), surface and soil temperatures were recorded manually three times a day at 8:00, 14:00, and 20: 00. Relative humidity was derived from wet and dry ball air temperatures based on standard meteorological methods. Two meteorological towers were also established in 1997 inside the Schima superba and Pinus elliotii forests in order to observe the vertical gradients of air temperature and relative humidity, with the sensors locating at 0.5 m, 2.0 m, 4.0 m and 9.0 m above the surface. Hourly temperature and humidity data were recorded automatically by the dataloggers (AMRS-I). We compared air and soil temperatures and air relative humidity among the three forests. The results showed that the Schima superba forest had the most significant capacity in decreasing both air and soil temperature and increasing air moisture. Air and soil temperatures within the Schima superba plantation were 0.1~0.5℃ and 0.3~2.5℃ lower than those within the Acacia mangium and Pinus elliotii plantations, respectively. The average moisture in Schima superba plantation was 1.2% higher than that of the other two forests, which had the similar annual average relative humidity (81.2%). Analysis on vertical temperature and humidity gradients showed that temperature increased with the increasing height in the wet season, but decreased in the cold dry season. Moisture decreased with increasing height both in the wet season and dry season. Possible impacts of microclimatic differences among the three forests on ecosystem structure, function, and ongoing successional process were discussed. Tree growth, forest structural changes, and soil properties of the three forests were analyzed based on the data from literature and other sources. We found that Schima superba forest also had better performance in retaining quality structural characteristics and improving soil status. Thus, we suggested that native plant species, such as Schima superba, should be chosen as pioneer species in restoring the primary forest vegetation in lower subtropical China.
出处
《生态学报》
CAS
CSCD
北大核心
2003年第8期1657-1666,共10页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目 ( 3 0 1 0 0 0 2 1 )
广东省自然科学基金资助项目 ( 0 1 0 5 5 1 )
中国科学院鹤山站开放基金资助项目
中国科学院知识创新工程项目资助项目~~
