Effect of cultivating croplands and grazing in arid grassland habitats on the conservation of melita

来源 :Science in China(Series C:Life Sciences) | 被引量 : 0次 | 上传用户:woaizhmx
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
In the study area (Yanjiaping Village, Hebei Province, China), grazing extensity varies at different loca-tions, small and discontinuous croplands are imbedded in some arid grassland, which are habitats for the melitaeine butterflies, Euphydryas aurinia and Melitaea phoebe. These two species of butterflies coexist in this area, in which grazing and cultivation are the main disturbances. Grazing and cultivation have a reciprocal effect on E. aurinia, rather than M. phoebe. We observed that E. aurinia preferred to occupy patches with moderate grazing and imbedded with small and discontinuous croplands, where E. aurinia also has high population density. The percentage of E. aurinia larval groups in the ribbings was significantly higher than that of M. phoebe, whereas larvae of both species tended to increase in recent years. Our data also showed that the population density and the patch occupancy rate of both E. aurinia and M. phoebe were the highest under moderate grazing. It indicates that cultivation of small and dis-continuous croplands within the patch has a significant effect on the population density of both spe-cies of melitaeine butterflies. Thus, to artificially create or maintain semi-natural habitats, comple-mented by moderate grazing, might be an ecological strategy to conserve melitaeine butterflies effec-tively. Considering the distinct impacts of cultivation and grazing on the population distribution and dynamics of the two different species, human disturbance in the mountainous area might be strategi-cally involved in proposing conservation plans for the target species in the future. In the study area (Yanjiaping Village, Hebei Province, China), grazing extensity varies at different loca-tions, small and discontinuous croplands are imbedded in some arid grassland, which are habitats for the melitaeine butterflies, Euphydryas aurinia and Melitaea phoebe. These two species of butterflies coexist in this area, in which grazing and cultivation are the main disturbances. Grazing and cultivation have a reciprocal effect on E. aurinia, rather than M. phoebe. We observed that E. aurinia preferred to occupy patches with moderate grazing and The percentage of E. aurinia larval groups in the ribbings was significantly higher than that of M. phoebe, than larvae of both a species tended to increase in recent years. Our data also showed that the population density and the patch occupancy rate of both E. aurinia and M. phoebe were the highest under moderate grazing. It indicates t hat cultivation of small and dis-continuous croplands within the patch has a significant effect on the population density of both spe-cies of melitaeine butterflies. Thus, to artificially create or maintain semi-natural habitats, comple-mented by moderate grazing, might be an ecological strategy to conserve melitaeine butterflies effec-tively. Considering the distinct impacts of cultivation and grazing on the population distribution and dynamics of the two different species, human disturbance in the mountainous area might be strateg-cally involved in proposing conservation plans for the target species in the future.
其他文献
针对我国工业锅炉燃煤细屑日趋增多,飞灰、漏煤损失及大气污染愈来愈严重的实际问题.率先提出了工业锅炉自身成型型煤的加工及燃烧方式,经大量的实验研究,得出了影响锅炉无粘结剂
9月20日 晴  每当我站在讲台上,我总会想起那平生第一次口语命题测试时的情景。   那是我们刚抽了序号和题目时,有的人暗暗高兴,有的人却愁眉苦脸。而我沾沾自喜地想:“关于考试的文章我还是读过不少的,选最精华的一段上去不就完了,真简单!”可是,口语命题测试并没有我想象的那么简单,因为,老师还要求5分钟以内讲完,而且准备的时间也只有5分钟。于是我用起了术语,这是我在今年全国新概念英语大赛上用过的,非
针对水暖改地热的方法和注意事项进行了论述。 For plumbing to geothermal methods and precautions are discussed.
8月5日晴在烈日炎炎的夏日,去河中玩一阵是最好不过的了。今天,我就和妹妹一起去河里玩摸鱼,一路上,妹妹开玩笑地说:“姐,你可别输给我啊!”我酷酷一笑:“小样,你还是等我给
货运管理信息化迫在眉睫大型企业铁路专用线承担企业内外铁路货物的运输,其运输组织主要由铁路行车组织和铁路货运组织构成。近年来,不少企业在行车组织管理方面投入一定 Fr
当品牌的树立和企业利益、社会责任发生矛盾时,企业该如何选择主持人:很多人在谈到品牌树立的时候说,品牌发展的下一个空间是社会责任,而社会责任是21世纪树立品牌的必由之路
心性修养的卓逸,以及海派文化的浸润,带来一种中西合璧的东西方文化结晶。办孩子喜欢的学校、教孩子喜欢的课程,学校以草根的情怀,致博雅的追求。走近华漕学校,你会发现校园
9月9日 晴  今天,我们在教室举行了一场别开生面的扳手腕对抗赛,老师分别为两队起了个响亮的名字——“飞龙队”“飞虎队”。呵,光听这名字,就能猜出比赛会有多么精彩了!同学们目睹了双方选手的风采。  比赛共分为三场,采取三局两胜制。第一局上场的选手是刘树杰和贾子剑同学。随着老师的一声令下,比赛开始了。他两的双手紧紧握在一起,手上的青筋暴起,如龙虎相争,互不相让。贾子剑同学紧咬牙关,眉头紧皱,好像要把
本文根据土中水势理论和室内、现场吸力试验结果指出:当WW_s时,毛细吸力等于晶层间吸力,也等于此种状态下的膨胀压力;在有上覆压力且充分供水时,用热传导吸力探头无法测出土
1.晚稻留高桩冬绿肥直播还田在晚稻收获前将红花草、满园花、腊菜等种子均匀直插于晚稻田中,晚稻采用留高桩或机械收割还田。其中留桩高度40厘米~45厘米,约80%稻草还田;机械收