Biocrusts benefit from plant removal
Biocrusts benefit from plant removal
复制标题
DOI：
10.1002/ajb2.1120
复制
发表时间：
2018-07-01
影响因子：
3
通讯作者：
Rudgers, Jennifer A.
中科院分区：
文献类型：
--
作者：
Dettweiler-Robinson, Eva;Sinsabaugh, Robert L.;Rudgers, Jennifer A.
研究前提：旱地的生产力可能取决于植物和生物结壳之间相互作用的敏感性。鉴于未来的气候变化，这是必不可少的，以了解如何相互作用可能是依赖于上下文与降水制度。此外，人们对这些生产者与地下生物群的额外相互作用知之甚少（例如，根、真菌、微型节肢动物）。我们评估的效果去除（如可能发生以下干扰）和净相互作用的植物和生物壳，并另外操纵的非生物和生物context.METHODS：我们建立了现场围隔包含草（Bouteloua gracilis）和周围的生物壳，然后修剪植物或热消毒的生物壳模拟旱地生产者的损失。为了测试降水模式的上下文依赖性，我们施加了一个大的，罕见的或小的，频繁的降水制度。网状屏障用于阻止可能耦合生产者动态的地下连接。生产力进行了评估，植物生物量和生物壳叶绿素含量。关键结果：生物壳叶绿素含量增加植物被删除时，比当他们在第一年，但只有在小，频繁的降水制度。与此相反，植物生长略有下降，生物结壳去除。第二年，植物生物量和生物壳叶绿素含量呈负相关，表明净竞争。地下连通性对整体生物结壳相对生产力的促进作用较弱，但对植物相对生产力的损害通常较弱。结论：改变的降水模式可以放大植物去除对生物结壳生产者的积极影响。此外，我们发现，地下网络有助于旱地生产力，促进生物结壳的性能。
PREMISE OF THE STUDY: Productivity in drylands may depend on the sensitivity of interactions between plants and biocrusts. Given future climate variability, it is essential to understand how interactions may be context-dependent with precipitation regime. Furthermore, little is known about the additional interactions of these producers with the belowground biota (e.g., roots, fungi, microarthropods). We evaluated the effect of removal (such as could occur following disturbance) and net interaction of plants and biocrusts and additionally manipulated the abiotic and biotic context.METHODS: We established field mesocosms containing grass (Bouteloua gracilis) and surrounding biocrusts, then clipped the plant or heat-sterilized the biocrust to simulate the loss of dryland producers. To test for context-dependency on the precipitation pattern, we imposed a large, infrequent or small, frequent precipitation regime. A mesh barrier was used to impede belowground connections that may couple the dynamics of producers. Productivity was assessed by plant biomass and biocrust chlorophyll content.KEY RESULTS: Biocrusts increased chlorophyll content more when plants were removed than when they were present in the first year, but only in the small, frequent precipitation regime. In contrast, plant growth slightly declined with biocrust removal. Plant biomass and biocrust chlorophyll content were negatively correlated in the second year, suggesting net competition. Belowground connectivity weakly promoted overall biocrust relative productivity, but was generally weakly detrimental to plant relative productivity.CONCLUSIONS: Altered precipitation patterns can amplify positive effects of plant removal on biocrust producers. Furthermore, we discovered that belowground networks contributed to dryland productivity by promoting biocrust performance.