Integrating trees into agricultural landscapes to enhance biodiversity and associated ecosystem services

植树造林是当前缓解气候变化和生物多样性危机的环境议程的首要任务。例如，苏格兰政府目前的目标是每年种植12,000公顷的树木，从2024年起增加到15,000公顷。农业用地覆盖了英国70%以上的土地，因此很可能很大一部分树木覆盖面积将扩大到农田。考虑到我们对乡村景观的诸多要求，以及树木覆盖的半永久性，确定能够最大限度地发挥生物多样性和树木带来的更广泛环境效益的空间安排至关重要。树木可以沿着土地节约（例如建立林地斑块）到土地共享（例如在将树木与作物或牲畜结合起来的农林业系统中）的梯度以一系列空间配置种植。虽然这两种战略都有可能带来一系列生物多样性效益，但它们不太可能是等同的。该研究的目的是评估将树木与粮食生产分离或整合的相对优点，以提供最大的生物多样性利益（重点关注无脊椎动物群落，因为它们具有不同的生态角色，支撑着对粮食生产至关重要的生态系统功能和服务）。需要解决的具体研究问题包括：1)农业景观中的无脊椎动物群落如何受到不同空间配置的树木的影响，代表了土地节约到土地共享管理方法的梯度？2)具有不同生活史和功能特征的无脊椎动物如何响应沿着土地共享-节约连续体植树，这对生态系统服务提供有什么影响？3)土地管理者是否更愿意在特定的空间配置中植树？这对植树策略的实施有什么影响？为了解决这些问题，将在种植树木的农业场地进行实地调查，这些树木在一系列空间配置中包括土地节约梯度到土地共享梯度。数据收集将侧重于地面捕食者（如瓢虫和蜘蛛），也有可能包括昆虫传粉者（如食蚜蝇、蜜蜂和蝴蝶），以涵盖更广泛的功能特征和生态系统服务。该学生将有机会访问现有的甲虫数据集（130种30000只）和蜘蛛数据集（103种4000只），这些数据集是在60个种植在前农业用地上的林地上记录的（WrEN项目的一部分），以及SRUC编制的甲虫功能特征数据库。

Tree planting is at the forefront of the current environmental agenda to mitigate climate change and the biodiversity crisis. For instance, the Scottish Government has a current target of planting 12,000 ha of trees per year, increasing to 15,000 ha from 2024. Agricultural land covers over 70% of the UK, so it is likely that a large proportion of tree cover expansion will take place on farmland. Given the many demands we place on rural landscapes, alongside the semi-permanency of tree cover, it is crucial to determine the spatial arrangements that maximise the biodiversity and wider environmental benefits derived from trees. Trees can be planted in a range of spatial configurations along a gradient of land-sparing (e.g. creating woodland patches) to land-sharing (e.g. in agroforestry systems that integrate trees with crops or livestock). Whilst both these strategies have the potential to deliver a range of biodiversity benefits, they are unlikely to be equivalent.The aim of this studentship is to assess the relative merits of separating versus integrating trees with food production to provide the greatest benefits for biodiversity (with a focus on invertebrate communities because of their diverse ecological roles which underpin ecosystem functions and services vital to food production). Specific research questions to address include:1) How are invertebrate communities in agricultural landscapes influenced by trees in various spatial configurations, representing a gradient of land-sparing to land-sharing management approaches?2) How do invertebrates with varying life histories and functional traits respond to tree planting along the land sharing-sparing continuum, and what implications does this have for ecosystem service provision?3) Are land managers more amenable to planting trees in certain spatial configurations than in others, and what implications does this have for the implementation of tree planting strategies? To address these questions, fieldwork will be conducted in agricultural sites where trees have been planted across a range of spatial configurations encompassing a gradient of land-sparing to land-sharing gradient. Data collection will focus on ground-dwelling predators (e.g. carabid beetles and spiders), with the potential to also include insect pollinators (e.g. hoverflies, bees and butterflies) to encompass a wider range of functional traits and ecosystem services. The student will have access to an existing dataset of beetles (30,000 individuals of 130 species) and spiders (4,000 individuals of 103 species) which have been recorded at 60 woodlands planted on former agricultural land (part of the WrEN project , and to a beetle functional traits database compiled by SRUC.