Restoration of native mangrove wetlands can reverse diet shifts of benthic macrofauna caused by invasive cordgrass
Restoration of native mangrove wetlands can reverse diet shifts of benthic macrofauna caused by invasive cordgrass
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DOI：
10.1111/1365-2664.12987
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发表时间：
2018-03-01
影响因子：
5.7
通讯作者：
Lin, Guanghui
中科院分区：
文献类型：
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作者：
Feng, Jianxiang;Huang, Qian;Lin, Guanghui
1.利用本地红树林进行生态置换并结合物理处理已成为控制互花米草入侵的有效方法。为了重建生态系统功能，在恢复过程中必须考虑大型底栖动物与其潜在食物资源之间的营养相互作用。在此，我们研究了大型底栖动物在中国南方3个不同入侵历史的红树林生态系统中的食物变化。对主要大型动物的碳和氮稳定同位素比率及其潜在食物来源进行了分析。计算了不同碳源对底栖动物食物的相对贡献，并比较了各采样点的大型底栖动物群落的同位素生态位宽度（包括凸形船体面积和标准椭圆面积）.研究结果表明，在3个地区互花米草群落中，来自米草的碎屑占优势大型动物有机碳源的80%以上。互花米草群落的外凸船体面积和标准椭圆面积均小于天然红树林，表明不同消费种群间存在明显的资源竞争。用本地红树林种秋茄替代互花米草可以逆转这些大型底栖动物物种的饮食，导致从同质的米草为主的饮食转变为更异质的藻类为基础的饮食。可能需要几十年的时间才能将食物网的相互作用恢复到受影响前的状态。即使是成熟红树林（> 40年）的大型底栖动物的食物也受到米草源有机质的影响.合成与应用。研究表明，利用本地红树林物种对入侵互花米草进行生态替代，可以逐步恢复食物网功能。然而，这种拆除和更换方法是一个漫长的过程，需要大量的人力和资源。此外，只要附近的大面积湿地被互花米草占据，本地生态系统将继续受到绳草的影响。因此，防止互花米草的定殖应成为中国南方海岸带生态系统管理的优先事项。
1. Ecological replacement using native mangrove species combined with physical treatments has become an effective method in controlling the spread of invasive cordgrass Spartina alterniflora. To re-establish ecosystem functions, trophic interactions between macrofauna and their potential food resources must be considered during the restoration process.2. Here, we examined the changes in the diets of macrofauna in three restored mangrove ecosystems with different invasion histories following the removal of S.alterniflora in southern China. Carbon and nitrogen stable isotope ratios for dominant macrofauna, as well as their potential food sources, were analysed. The relative contributions of the different carbon sources to the diets of benthic macrofauna and isotopic niche width, including convex hull areas and standard ellipse areas of the macrofaunal community, were then calculated and compared among sampling sites in each region.3. Our results indicated that Spartina-derived detritus contributed to >80% of the organic carbon sources of dominant macrofauna in the S.alterniflora communities in all three regions. Spartina alterniflora communities had lower convex hull areas and standard ellipse areas than natural mangrove forests, indicating significant resource competition among different consumer populations. Replacing S.alterniflora with the native mangrove species Kandelia obovata could reverse the diets of these macrofaunal species, resulting in a shift from homogeneous Spartina-dominated diets to more heterogeneous algae-based diets. It could take several decades to restore food web interactions to a pre-impacted state. Even the diets of macrofauna in mature mangrove (>40years) remained affected by the Spartina-derived organic matter.4. Synthesis and applications. Our study reveals that the ecological replacement of invasive Spartina alterniflora using native mangrove species could restore food web function gradually. However, this removal and replacement approach is a long process and requires significant manpower and resources. Furthermore, the native ecosystem will continue to be influenced by the cordgrass as long as large areas of wetland nearby are occupied by S.alterniflora. Consequently, preventing the colonization of S.alterniflora should be a priority for coastal ecosystem management in southern China.