Ontogenetic changes in dietary carbon sources and trophic position of two co-occurring horseshoe crab species in southwestern China
Ontogenetic changes in dietary carbon sources and trophic position of two co-occurring horseshoe crab species in southwestern China
复制标题
中国西南地区两种共存鲎的膳食碳源和营养位置的个体发育变化
DOI：
10.3354/ab00670
复制
发表时间：
2017-01-01
期刊：
影响因子：
1.4
通讯作者：
Hsieh, Hwey-Lian
中科院分区：
文献类型：
--
作者：
Fan, Lan-Feng;Chen, Chang-Po;Hsieh, Hwey-Lian
了解哪些食物来源是营养重要的苗圃场是至关重要的，在亚洲的马蹄蟹种群减少的保护。我们使用Δ C-13和Δ N-15值来定义生活阶段的饮食碳源和营养位置的变化的2个共存的马蹄蟹种，中国，广西，珠江湾的红树林和海草植被的河口，中国。δ C-13信号在T. tridentatus和C.圆尾虫在种间和种内不同的生活阶段之间存在差异，最大的差异发生在较早的生活阶段（5-7龄; 20-30 mm的前体宽度）。生活阶段特定的饮食是一致的，已知的栖息地使用的2马蹄蟹物种，与T。tridentatus反映了海草碳源的轻微富集，C.反映较轻的沉积物颗粒有机物的影响的圆尾（POM; -15.1 vs.类似于-15.8%）。总体而言，海草贡献最大的两个物种的膳食碳（类似的60%），其次是沉积物POM（35%）。δ N-15标记在种间相似（相似率为11.6%），C.圆尾蟹成虫比幼蟹的信号稍丰富（12.7%比11.6%），所有鲎都处于次级消费者营养级。珠江湾马蹄蟹的三角洲N-15签名比那些更城市化的沃茨，可能是由于较低的人为氮负荷轻。我们的数据和以前的研究表明，有效的国际和国家战略，保护受威胁的亚洲马蹄蟹将受益于纳入努力，保护海草和红树林栖息地。
Understanding which food sources are nutritionally important at nursery grounds is critical in the conservation of the dwindling populations of horseshoe crabs in Asia. We used delta C-13 and delta N-15 values to define life-stage changes in dietary carbon sources and trophic position of 2 co-occurring horse-shoe crab species, Tachypleus tridentatus and Carcinoscorpius rotundicauda, in a mangrove- and sea-grass-vegetated estuary, Pearl Bay, in Guangxi, China. delta C-13 signatures in tissues of T. tridentatus and C. rotundicauda varied between species and among life stages within species, with the greatest differences occurring among earlier life stages (instars 5-7; 20-30 mm prosomal width). Life-stage specific diets were consistent with known habitat use by the 2 horseshoe crab species, with T. tridentatus reflecting slightly enriched seagrass carbon sources and C. rotundicauda reflecting influences of lighter sediment particulate organic matter (POM; -15.1 vs. similar to -15.8%). Overall, seagrass contributed most to dietary carbon of both species (similar to 60%), followed by sediment POM (35%). delta N-15 signatures were similar between species (similar to 11.6%), with C. rotundicauda adults exhibiting a slightly more enriched signal than juveniles (12.7 vs. 11.6%), and all horseshoe crabs occupied secondary consumer trophic levels. The delta N-15 signatures in horse-shoe crabs at Pearl Bay were lighter than those from more urbanized waters, likely due to lower anthropogenic nitrogen loading. Our data and those of previous studies suggest that effective international and national strategies for conserving threatened Asian horseshoe crabs would benefit from incorporating efforts to protect seagrass and mangrove habitats.