莫宗明 譚長(zhǎng)強(qiáng) 方小玉 李偉彬

摘 要 為調(diào)整森林樹(shù)種結(jié)構(gòu)，提高森林質(zhì)量和綜合效益，廣西東部的國(guó)有大桂山林場(chǎng)從桂西北天然分布區(qū)引種香合歡（Albizia odoratissima）。對(duì)其4 年生引種林分進(jìn)行了調(diào)查，結(jié)果表明：香合歡具有較好的適應(yīng)性，林木保存率達(dá)到95.3%，平均樹(shù)高4.19 m，平均胸徑4.6 cm，平均冠幅2.36 m，郁閉度0.5，樹(shù)高和胸徑均呈正態(tài)分布，主干通直和較通直的林木比例高達(dá)77.4%，林木沒(méi)有遭受中度及以上林業(yè)有害生物為害，適宜培育用材林。

關(guān)鍵詞 林木引種；人工造林；造林成效；香合歡

中圖分類號(hào)：S725.1?????? 文獻(xiàn)標(biāo)識(shí)碼：A?? doi：10.13601/j.issn.1005-5215.2024.04.012

Preliminary Report on the Afforestation Effect of Albizia odoratissima Introduced to the East of Guangxi

Mo Zongming1，Tan Changqiang2，F(xiàn)ang Xiaoyu3，Li Weibin4

（1. State-owned Daguishan Forest Farm of Guangxi Zhuang Autonomous Region，Hezhou 542899，China; 2. Institute of Forestry Sciences of Guangxi Zhuang Autonomous Region，Nanning 530002，China; 3. Center for Rescue Research of Terrestrial Wildlife and Monitoring of Epidemic Diseases in Guangxi Zhuang Autonomous Region，Nanning 530028，China; 4. Nanning Wildlife Conservation Station of Guangxi Zhuang Autonomous Region，Nanning 530022，China）

Abstract In order to adjust the structure of forest species and improve forest quality and comprehensive benefits，the State-owned Daguishan Forest Farm located in the east of Guangxi introduced Albizia odoratissima from its natural distribution area in the northwest of Guangxi. The four-year-old introduced forest stands were investigated. The results showed that Albizia odoratissima had good adaptability，the preservation rate of trees reached 95.3%，the average tree height was 4.19 m，the average DBH was 4.6 cm，the average crown width was 2.36 m，and the canopy density was 0.5. The tree height and DBH showed normal distribution，and the proportion of straight and straighter trunk trees was as high as 77.4%. The trees were not damaged by moderate and above forestry pests，and were suitable for cultivating timber forests.

Key words forest tree introduction; artificial afforestation; afforestation effect; Albizia odoratissima

香合歡（Albizia odoratissima）又名土格木、黑格、鐵掖蒿、香須樹(shù)等，是豆科（Leguminosae）合歡屬落葉喬木，列入《主要栽培珍貴樹(shù)種參考名錄（2022年）》，在廣西壯族自治區(qū)主要天然分布于桂西北[1]，根系發(fā)達(dá)，萌芽力強(qiáng)，耐貧瘠、耐干旱，具有根瘤固氮作用[2]，能改良土壤和保持水土。其木材堅(jiān)硬[3]，紋理致密，心材顏色較深，多呈巧克力色、褐色，抗蟲耐腐，不容易開(kāi)裂和變形，是家具、木地板、建筑等優(yōu)質(zhì)用材，具有極高的經(jīng)濟(jì)價(jià)值。冠形良好，具有較高的園林觀賞價(jià)值。

廣西國(guó)有大桂山林場(chǎng)位于廣西東部，部分林地由于長(zhǎng)時(shí)間營(yíng)造單一樹(shù)種桉樹(shù)（Eucalyptus spp.），林地土壤出現(xiàn)輕度退化，土壤有機(jī)質(zhì)、全氮、銨態(tài)氮、硝態(tài)氮、全鉀、速效鉀等多種養(yǎng)分含量均不同程度下降[4]，養(yǎng)分供應(yīng)不平衡，桉樹(shù)生長(zhǎng)不良，單位面積木材產(chǎn)量低，森林生態(tài)系統(tǒng)穩(wěn)定性不高。因此，適當(dāng)引種香合歡等高價(jià)值珍貴樹(shù)種，合理調(diào)整森林樹(shù)種結(jié)構(gòu)，充分發(fā)揮森林生態(tài)效益、經(jīng)濟(jì)效益、社會(huì)效益等多功能效益，對(duì)促進(jìn)森林可持續(xù)經(jīng)營(yíng)和助力鄉(xiāng)村振興具有重要意義。

1 材料與方法

1.1 材料

1.1.1 試驗(yàn)地概況 香合歡引種造林試驗(yàn)地位于廣西壯族自治區(qū)東部的賀州市八步區(qū)國(guó)有大桂山林場(chǎng)六排分場(chǎng)，111°41′54″E， 24°8′21″N，海拔245 m。地處南亞熱帶季風(fēng)氣候區(qū)，年平均氣溫19.7? ℃，7月份平均氣溫30? ℃，1月份平均氣溫14? ℃；無(wú)霜期300 d，冬暖夏涼，年平均日照時(shí)數(shù)1 751 h；年平均降水量1 551 mm，降雨主要集中在5—8月，雨熱同季。林地成土母巖為砂頁(yè)巖，土壤類型為赤紅壤，土層厚度45 cm，土壤pH為5.5。造林前林地類型為桉樹(shù)商品林采伐跡地。