盐沼草对桐花树人工林污损动物危害的生物防治研究

以3个树高规格的桐花树(Aegiceras corniculatum)苗木与茳芏(Cyperus malaccensis)、沟叶结缕草(Zoysia matrella)、芦苇(Phragmites australis)和南水葱(Scirpus validus var.laeviglumis)4种盐沼草为材料,在广西北仑河口区高程约为220cm的新造潮间带裸滩上树-草混种,探索利用盐沼草减轻污损动物对人工红树林危害的生物防治效果。结果显示:沟叶结缕草和茳芏适应人造潮间带生境,南水葱和芦苇长势较差。附着盐沼和红树的污损动物有19种,其中潮间藤壶(Balanus littoralis)、白条地藤壶(Euraphia withersi)、黑口滨螺(Littorina melanostoma)和粗糙滨螺(L.scabra)为优势种。4种盐沼草中长势较好的茳芏和沟叶结缕草丛受污损程度较轻,南水葱和芦苇丛显著较严重。表明混种茳芏和沟叶结缕草可有效减轻桐花树苗木受污损程度,这两类树-草混种处理区苗木的高度、叶数、枝数、枝下高和存活率等指标均较优于其他处理区。综合而言,茳芏混种桐花树构建"盐沼草-红树协同生态修复体系"对于裸滩红树林防污有较高应用价值。

Biological Prevention Method for Reducing the Fouling Fauna Damage to the Young Transplanted Aegiceras corniculatum Mangrove Trees by Mix-culturing with Saltmarsh

Mix-culturing of Aegiceras corniculatum (AC) trees in three height grades with four species of saltmarsh on the man-made intertidal bare flat at an elevation of about 220 cm Yellow Sea Datum in Beilun estuarine area of Guangxi, China, to which the seaward and landward single-species treatment areas were designated as contrast, was carried out to explore the biological method for reducing the fouling fauna threatening on mangrove trees.The results showed that Cyperus malaccensis (CM) and Zoysia matrella (ZM) adapted better to the man-made intertidal flat, while Scirpus validus var.laeviglumis (SV) and Phragmites australis (PA) grew worse.19 species of fouling fauna occurred on saltmarsh and mangroves, among which Balanus littoralis, Euraphia withersi, Littorina melanostoma and L.scabra were the major dominant species.Among the four saltmarsh species, the fouled degrees on CM and ZM were significantly less than those on other two species.The mix-culturing of saltmarsh CM or ZM with mangrove tree AC could efficiently reduce the fouling damage, resulting in better tree growth indexes i.e.tree height, leaf number, branch number, branch conservation and survival rate than those in single-species treatment areas.In general, a saltmarsh-mangrove cooperating ecological conservation system jointly acted by CM and AC could be a more practical solution to fouling reduction for the mangrove afforestation on bare flat.