浙江不同河口滩涂秋茄树幼苗生长适应性试验

2019年5-6月,采用浙江龙港种质和福建泉州种质的1年生秋茄树Kandelia obovata容器苗和胚轴在浙江省沿海的宁波钱塘江河口、台州椒江河口和温州瓯江河口滩涂进行种植试验,2020年4月,调查了幼苗生长及土壤化学性质,对比分析秋茄树幼苗生长指标、叶片参数和生物积累量的差异。结果表明,瓯江河口土壤含盐量、有机质、水解氮、有效磷、速效钾与钱塘江河口和椒江河口土壤间存在显著差异(P<0.05),但均满足秋茄树正常生长要求;在三个试验地中,龙港秋茄树种质的保存率均显著高于泉州种质(P<0.05);在钱塘江口,龙港秋茄树种质容器苗和胚轴苗的保存率分别为72.92%和82.78%,而泉州种质仅有33.47%和15.28%,且龙港种质容器苗的分枝数显著高于泉州容器苗(P<0.05),但泉州种质胚轴苗的高生长显著大于龙港种质(P<0.05);在三个试验地中,龙港秋茄树种质容器苗的叶片数和叶面积均显著高于泉州种质(P<0.05),胚轴苗则相反,而泉州秋茄树种质的叶片长和叶片宽在瓯江河口最大,椒江河口最小,龙港种质在三个试验地间均无明显差异;秋茄树幼苗的根、茎、叶干质量和生物积累量均表现出瓯江河口>钱塘江河口>椒江河口,龙港秋茄树容器苗各生物量指标均高于泉州种质,而胚轴苗正好相反。因此,在宁波和台州河口滩涂开展红树林营建适合选择龙港秋茄树种质容器苗,而在温州适合选择龙港秋茄树种质胚轴苗。

Experiment of Kandelia obovata Seedlings in Different Estuaries in Zhejiang

In May and June 2019,1-year container seedlings and hypocotyl of Kandelia obovata which were from Quanzhou city,Fujian Province and Longgang city,Zhejiang Province were planted on estuaries of the Qiantang River in Ningbo,Jiaojiang River in Taizhou and Oujiang River in Wenzhou.In April 2020,the seedling growth and soil chemical properties were investigated,and the differences of growth indexes,leaf parameters and biomass of K.obovata seedlings were analyzed..The results showed that the content of soil salt,organic matter,hydrolyzed nitrogen,available phosphorus and available potassium in the Oujiang river estuary had significantly difference with that in the Qiantang river estuary and Jiaojiang river estuary,but K.obovata could grow well in tested estuaries.In the three experimental sites,the preservation rate of K.obovata germplasm from Longgang was significantly higher than that from Quanzhou K.obovata germplasm(P<0.05).The preservation rate of container seedlings and hypocotyl of Longgang germplasm in the Qiantang river estuary was 72.92%and 82.78%,respectively,while that of Quanzhou was only 33.47%and 15.28%.The branching number of container seedlings of Longgang germplasm was significantly higher than that of Quanzhou germplasm in the Qiantang river estuary,but the height growth of hypocotyl seedlings was the opposite.Compared with Quanzhou germplasm,container seedlings of the Longgang exhibit higher increases in leaf number and leaf area in the three experimental sites,the hypocotyl seedlings were reverse.The leaf length and leaf width of the Quanzhou germplasmwere the largest in the Oujiang River,and the smallest in the Jiaojiang River,while the Longgang germplasm had no significant difference in the three experimental sites.The sequence of root,stem,leaf dry weight and bioaccumulation of K.obovata from high to low was:Oujiang River>Qiantang River>Jiaojiang River.The biomass indexes of K.obovata container seedlings from Longgang were all higher than those from Quanzhou germplasm,but the hypocotyl seedlings were the opposite.Therefore,the container seedlings of Longgang K.obovata germplasm should be selected for mangrove construction in Ningbo and Taizhou estuarine tidal flat,while hypocotyl seedlings of K.obovata germplasm are preferred in Wenzhou.