以福建省长乐市大鹤国有防护林场的6种相思为对象,进行叶绿素荧光参数的冬季日变化规律观测。结果显示:各相思树种黑暗中最大可变荧光强度(FV)均于午间及午后达到1 d中相对较大值;1 d内PSⅡ最大光能转换效率和PSⅡ潜在活性,肯氏相思整体要高于其余5种相思,而厚荚相思、大叶相思、马占相思相对较低。结合其林分保存率可知,肯氏相思、纹荚相思、卷荚相思在冬季较适应闽东沿海沙地生境。

This paper compared the winter diurnal variation rules of chlorophyll fluorescence parameters of 6 Acacia species in Dahe State-Owned Shelterbelts Field in Changle City of Fujian Province.The result showed that the chlorophyll fluorescence parameters Fv of all Acacia tree species from midday to afternoon achieved a relatively large value of the day ;in one day ,the maximum light conve-rtion efficiency of PSII and its potential activity of Acacia cunninghamii was higher than the rest of the 5 kinds of Acacia on the whole,however,Fv/Fm and Fv/Fo values of A.crassicarpa,A.auriculiformis and A.mangium were relatively low.Combined with the preserving rate of trees , A.cunninghamii,A.aulacocarpa and A.cincinnata were more adapt to the coastal sand in the winter.

以东南沿海防护林6种相思树种为研究对象，通过跟踪测定其不同季节叶绿素荧光参数，进一步评价各树种对沿海沙地气候环境的适应能力。结果显示：卷荚相思夏季和冬季PSⅡ最大光能转化率和潜在活性均低于春季和秋季，表明夏季高温干旱和冬季低温均会制约其生长；大叶、厚荚及马占相思冬季PSⅡ最大光能转化率和潜在活性较小，生长状况较差；肯氏相思和纹荚相思的Fv/Fm及Fv/Fo 值冬季相对较高，其中季节更替对肯氏相思Fv/Fm 及Fv/Fo 值变化影响最小，整体生长状况较好。结合林分生长情况可知，大叶、厚荚及马占相思对东南沿海沙地环境适应能力较差；肯氏相思和纹荚相思能够适应沿海防护林的复杂环境，具有较高的推广种植潜力。

The adaptability to the climate and coastal sand environment of six species from genus Acacia grow-ing in the coastal shelterbelt in southeast China was evaluated by successive determination of the seasonal change in chlorophyll fluorescence parameters of each specie.The results showed that the maximum light conversion efficiency of PSII and its potential activity of Acacia cincinnata in the summer and winter seasons were lower than those of in the spring and autumn,indicating that either the high temperature and drought in the summer or the low tempera-ture in the winter would restrain the growth of A.cincinnata.The maximum light conversion efficiency of PSII and the potential activity of A.crassicarpa,A.auriculiformis and A.mangium were relatively lower,and these species grew poorer than the others.The Fv/Fm and Fv/Fo values of A.cunninghamii and A.aulacocarpa were relatively higher,while these indexes were not much influenced by the change in seasons,so these two species generally g

为研究马占相思在早期的生长规律,为其保护、培育和指导规模化生产提供理论依据,以福建漳浦中西国有林场15 a生马占相思为研究对象,通过树干解析,求出树高、胸径、材积与年龄之间的关系曲线.结果表明:15 a生的马占相思在早期生长中生长速度较为恒定,干形削尖.研究结果可用于指导马占相思的规模化生产.

In order to study the growth low of Acacia mangium in early,for protecting,nurturing and guidance to provide a theoretical basis for large-scale production,the Western State Forest Farm in Zhangpu,Fujian regarded the A. mangium,15 years old,as the research object.The author obtained relationship curve between the tree height,breast diameter,volume and age through the stem analysis,thus achieving the growth law of A. mangium.The results showed that 15 years old A. mangium had constant rate of growth in the early growth,sharpened stem form.The study on the growth rule of A. mangium could be used to guide the large-scale production.

为了找出最适宜于越南中部山区、预期综合环境效益最佳的、更利于生态平衡的农林复合模式，该研究以越南和平水电站库区4种主要农林复合模式：马占相思树（Acacia mangium）-玉米（Zea mays）、马占相思树-木薯（Manihot esculenta crantz）、赤桉树（Eucalyptus camandulensis）-旱稻（Oraza sativa）和马占相思树-木薯-玉米为研究对象，采用盖度、土壤理化性质、土壤蓄水能力、水土保持能力等指标进行环境效益的比较，最后得出的结论为：在4种农林复合模式中，马占相思树-木薯-玉米复合模式具有最高的水土保持效益和综合环境效益；赤桉树-旱稻复合模式的水土保持效益和综合环境效益均最低；实践中应该增加前者的种植面积，限制和减小后者的种植面积。在马占相思树-木薯-玉米复合模式的基础上加以改进，提出了预期综合环境效益更好的马占相思树-木薯-玉米-肉桂（Cinnamomum cassia）复合模式，为农林复合系统在和平水电站库区的应用提供更好的选择，同时也为世界上有类似气候环境条件的地区农林复合模式的采用提供参考。

Nowadays, agroforestry farming is a major issue in Vietnamat midland and mountainous region as it has to satisfy the demand of forest production and ecosystem protection. Compared to some other types of forest, agroforest has demonstrated outstanding strength as it provides landowners with early and fast income generation. Therefore, developing agroforest becomes a trend when the research on land use gets much attention. However, environmental efficiency of agroforest is quite varied and closely reliable on the structure of the forest system. Taking into consideration of both environmental condition and the efficiency at the same time is significant not only in evaluating the current situation of the forest but also in improving its structure, thereby reaching environmental goals. Nevertheless, there is a shortage of research on above problem in Hoa Binh hydropower reservoir environment. Due to this restriction many agroforests were in failure to enhance their economic and pr

相思树和桉树等树种因其生长迅速、耐性好以及适合制作纸浆等特点,近年来在华南地区大面积种植,带来了巨大的经济利益,但是相思树和桉树如何影响林下土壤生物多样性和土壤肥力还不清楚,科学评价其林下土壤健康水平十分必要。土壤线虫的种类和数量十分丰富,在土壤食物网各营养级中占据重要位置,对土壤环境变化反应敏感,作为土壤健康的指示生物被广泛应用。本文以幼龄厚荚相思Acacia crassicapa和尾叶桉Eucalyptus urophylla人工林为研究对象,于干季和湿季分别对2个林分根区和非根区土壤线虫进行研究,探讨土壤线虫这种指示生物的数量、各营养类群比例和多样性的变化规律,以及它们和环境因子的关系。主要结果表明:(1)厚荚相思土壤线虫总数为每公斤干土6 741条,显著高于尾叶桉线虫总数的28.3%。厚荚相思人工林土壤食细菌线虫的百分比相比尾叶桉人工林高6.3%,且差异显著。(2)土壤线虫的群落组成变化具有明显的季节波动,湿季土壤食细菌线虫比例上升,而植物寄生线虫的比例下降,多样性指数由干季的0.87减小到0.75,统计差异均达到了显著水平。(3)根区比非根区显著提高了线虫数量的89.1%,这是由根区积累更多的有机碳和总氮引起的。总之,厚荚相思人工林为土壤自由生活线虫提供了优良环境,且在幼龄期没有表现出土壤酸化,生态效应优于尾叶桉人工林,在华南地区人工林营林过程中可适当增加厚荚相思林分面积。

Wide areas of Acacia crassicapa and Eucalyptus urophylla were planted in South China recently due to their rapid growth, strong tolerance and suitability for paper pulp. However, it is still not clear how these two tree species impact soil biodiversity and fertility. It is necessary to evaluate their soil health condition scientifically. The number and variety of soil nematodes are abundant. Soil nematodes occupy the key positions in trophic levels of soil food web and are sensitive to environmental changes. As indicator of soil health, nematodes are used in ecology widely. In this study, soil nematodes were investigated in young Acacia crassicapa and Eucalyptus urophylla plantations with different seasons and sampling positions, to analyze the patterns of soil nematode individuals, community composition and diversity index, as well as relationships with environmental factors. The main results showed that:(1) Total nematode individuals in Acacia crassicapa plantation were 674.1/100 g d