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[目的]为了了解洞庭湖区喜旱莲子草的发生、分布和危害情况。[方法]对洞庭湖区的6个不同生境的喜旱莲子草的分布、发生及危害情况进行了随机取样调查研究。[结果]喜旱莲子草普遍分布于河道、沟渠、路边、水塘、湿地、水田和旱地等生境,其发生频率均为100%。分布量多的生境是沟渠和湿地,其盖度平均为70.5%和88.4%。生长在河道和活水沟渠较其他生境表现为茎蔓长(分别为301 cm2、24 cm)、粗壮、组织幼嫩,茎蔓节间长(分别为9.7 cm8、.0 cm),其最长分枝多在中部且最长分枝长度(分别为93 cm6、6 cm)也相应较长。[结论]喜旱莲子草是河道、沟渠、水塘、湿地生境内发生量最大的优势种群,严重阻塞河道、沟渠,影响水产养殖,降低物种丰富度,防除困难,增加农业生态经济系统成本。
[Objective] To understand the occurrence, distribution and harm of Alternanthera philoxeroides in Dongting Lake. [Method] The distribution, occurrence and damage of Alternanthera philoxeroides in six different habitats in Dongting Lake area were randomly sampled and investigated. [Result] Alternanthera philoxeroides was widely distributed in habitats such as rivers, ditches, curbs, reservoirs, wetlands, paddy fields and drylands, with the frequency of 100%. Habitats distributed more are ditches and wetlands, with an average cover of 70.5% and 88.4%. Growing in the river channels and living ditches than other habitats showed stems and vines (301 cm 2 and 24 cm, respectively), sturdy, with young tissue and long stems (9.7 cm 8, .0 cm, respectively) Branches in the middle and the longest branch length (93 cm6,6 cm, respectively) are also correspondingly longer. [Conclusion] Alternanthera philoxeroides was the dominant species in the rivers, ditches, reservoirs and wetlands habitat. It seriously blocked rivers and ditches, affected aquaculture, reduced the species richness, prevented and eliminated the difficulties and increased the cost of agro-ecological economic system.