题干

紫茎泽兰是我国危害严重的外来入侵植物,调查其在不同入侵生境中的生长情况,结果如表:

入侵生境

幼苗密度(株/m2

成熟植株密度(株/m2

成熟植株高度(cm)

草地

468

123

120

人工林

548

95

115

自然林

688

64

84

回答下列问题:

(1)紫茎泽兰的种群密度可采用____ 法调查.紫茎泽兰可产生大量种子,其生态适应性很强,如果侵入地区能提供理想的生长环境,其群众数量将呈____ 型增长.

(2)从不同生境的幼苗密度来看,最适宜紫茎泽兰定居的生境是____ ;从成熟植株的密度和高度来看,最容易受紫茎泽兰入侵的生境是____ ,综合来看,与草地和人工林相比自然林具有较强的____ 稳定性.

(3)泽兰实蝇是紫茎泽兰的专食性天敌.泽兰实蝇将卵产生在植株的茎尖,孵化后的幼虫蛀食幼嫩部分,并在植株顶端形成虫瘿,阻碍植株生长和繁殖.两者的种间关系属于____ .

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答案(点此获取答案解析)

样方,J,自然林,草地,抵抗力,寄生

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