Management of a Population of the Federally Endangered Xyris tennesseensis (Tennessee Yellow-Eyed Grass)
Management of a Population of the Federally Endangered Xyris tennesseensis (Tennessee Yellow-Eyed Grass)
复制标题
联邦濒危田纳西黄眼草种群的管理
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
R. Boyd
中科院分区：
文献类型：
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作者：
J. M. Moffett;R. Boyd
摘要一项为期3年的研究，以确定削减灌木的影响，遮蔽了一个人口的Xyris tennesseensis Kral居住的石灰质渗漏沼泽的山脊和山谷生态区。灌木被削减到地面水平的小地块和Xyris开花，分株数（分株被定义为产叶茎）和幼苗数量进行了监测，在三个后处理季节。访花也被记录下来，以确定是否灌木切割增加了可能授粉花的昆虫访花的可能性。此外，还对该地点的种子库进行了描述和定量。灌木切割显着增加开花的Xyris网站上，但只有前两个赛季：第三个赛季开花下降，可能是由其他草本植物的竞争，响应增加的光照水平。灌木扦插也显著增加了幼苗产量，但没有发现Xyris分株数量的显著增加。没有Xyris种子银行。我们的结论是，切割灌木可以刺激Xyris繁殖的短期内，但长期管理必须平衡这种好处与其他非Xyris graminoids的竞争增加。沼泽的管理应努力使不同程度的木质植被覆盖和暴露的矿物质土壤的微生境镶嵌。
ABSTRACT A 3-yr study was conducted to determine effects from cutting shrubs that were shading a population of Xyris tennesseensis Kral inhabiting a calcareous seepage fen of the Ridge and Valley Ecoregion. Shrubs were cut to ground level on small plots and Xyris flowering, ramet numbers (a ramet is defined as a leaf-producing stem) and seedling numbers were monitored during three post-treatment seasons. Floral visitation was also documented to determine if shrub cutting increased the likelihood of floral visits by insects that might pollinate flowers. In addition, the seed bank of the site was described and quantified. Shrub cutting significantly increased flowering of Xyris on the site, but only for the first two seasons: by the third season flowering declined, likely caused by competition from other herbaceous species responding to the increased light levels. Shrub cutting also significantly increased seedling production, but no significant increase in the number of Xyris ramets was found. Floral visits were significantly more frequent to Xyris flowers located on cut plots. There was no Xyris seed bank. We conclude that cutting shrubs can stimulate Xyris reproduction for a short period but that long term management must balance this benefit with the resulting increased competition from other non-Xyris graminoids. Management of the fen should strive for a mosaic of microhabitats with varying degrees of woody vegetative cover and exposed mineral soil.