Data from: Enhancing plant diversity in a novel grassland using seed addition

1.Restoration of novel ecosystems to a historical benchmark may not always be possible or advisable. Novel ecosystems may be managed by targeting specific components and accepting the novelty of other ecosystem attributes. The feasibility of this component-wise management of novel ecosystems has rarely been tested.

2.In a novel grassland, where C3 grasses have replaced C4 grasses, nutrients have been elevated, and diversity has been lost due to a history of agricultural land use, we aimed to return diversity using seed addition, without altering the dominant grass matrix or nutrient status. Using direct seeding, with and without soil disturbance, we assessed the ability of 10 species of native forbs to establish.

3.Eight of the ten seeded species established in the first year. Soil disturbance increased establishment success by 50%, while high levels of exotic cover decreased it by 24%. Establishment was inversely related to total plant cover at sowing, with a 10% increase in initial plant cover decreasing establishment by 47%.

4.By the third year, six of the eight species persisted and five were flowering. Survival and reproduction in the third year was not associated with the soil disturbance treatment or plant cover.

5.Synthesis and applications. We show that native plant species can be re-established in grasslands where abiotic and biotic conditions are novel relative to their reference state. This suggests that the conservation value of novel ecosystems can be enhanced using simple restoration tools that target specific ecosystem components.

1. 将新型生态系统（novel ecosystem）恢复至历史基准状态往往并非总能实现，也未必适宜。新型生态系统可通过靶向特定组分、保留其余生态系统属性的新颖性来进行管理。目前极少有研究对这种分组分管理新型生态系统的可行性开展验证。
2. 本研究针对一处因历史农业土地利用，出现C3草本取代C4草本、养分水平升高、物种多样性丧失的新型草原，旨在通过添加种子的方式恢复物种多样性，且不改变优势草本群落结构或养分状态。我们设置了有、无土壤扰动的直接播种处理，评估了10种本土非禾本科草本植物的定植能力。
3. 十个播种物种中有八个在第一年成功定植。土壤扰动使定植成功率提升了50%，而高外来物种盖度则使其降低了24%。定植成功率与播种时的总植物盖度呈负相关：初始植物盖度每增加10%，定植成功率便会下降47%。
4. 至第三年，八个定植物种中有六个存活，其中五个开花。第三年的植株存活与繁殖情况与土壤扰动处理及植物盖度均无关联。
5. 综合与应用：本研究证实，在非生物与生物条件相较于参照状态发生改变的草原中，仍可重新定植本土植物物种。这表明，通过靶向特定生态系统组分的简易恢复手段，可提升新型生态系统的保护价值。