Managing landscapes for biodiversity during rapid climate change.

随着气候变暖，所有野生物种都必须适应或适应，才能生存下来。我们通过研究以前冰河时代之后的气候变化得知，地球上所有温带地区的物种都通过改变自己的地理范围来适应，跟随着气候的指引。我们也有证据表明，许多物种现在正在改变它们的活动范围，但大多数似乎没有跟上气候的步伐。问题是，与农业集约化和工业化之前的时代相比，大多数物种的自然(或半自然)栖息地现在很少，而且高度分散。当一个物种的栖息地被限制在陆地面积的一小部分时，它就很难在其活动范围的凉爽边缘入侵新的领土：它很容易被困在孤立的栖息地碎片中，最终随着气候变得不适合而灭绝。这是对保护组织和政府重建和恢复栖息地的重大刺激，以重新连接潜在的孤立种群。然而，认为我们可以将某些栖息地的面积恢复到史前水平是不现实的。例如，在英国，林地曾经是主要的栖息地。为了有效地保护英国的生物多样性，我们需要就以下问题做出明智的决定：(A)多少林地足以保护大多数物种，以及(B)如何在最有利于范围转移的地方创造林地。我们还必须找到一种方法，当我们不知道现在限制每个物种分布的所有因素(从温度和降雨到与其他物种的相互作用)，也不能可靠地预测它们需要转移的方向和距离时，我们必须找到一种继续进行的方法。这项研究将通过找到一种通用的栖息地创建策略来帮助这一决策，该策略将适用于大多数景观中的大多数物种。我们将测试一些策略-所有策略都以数字规则的形式来决定，在给定现有地貌的情况下，下一步选择哪个地块进行转换。作为现有景观的例子，我们将使用英国的真实景观，栖息地信息来自我们的项目合作伙伴森林研究和来自卫星的“2007年土地覆盖地图”。我们将根据动植物物种入侵景观的模拟来判断这些策略(假设它们从任何一个边缘的少量种群开始)。我们模拟物种特征的差异(例如栖息地专门性、繁殖率和扩散能力)将基于在所有已有数据的物种中观察到的差异。我们希望这将产生代表整个社区的结果，而不是只关注几个经过充分研究的物种。我们还将在我们的模拟中包括遗传信息-遗传多样性是生物多样性的一个重要方面，有时被忽视，随着种群在范围扩大期间通过栖息地“瓶颈”，这一方面可能会急剧减少。基于模拟结果，我们将能够根据生存物种的比例和这些种群中生存的遗传多样性比例对景观进行排名。我们的研究结果将对规划者和保护组织有用，也对任何有兴趣创造栖息地以造福野生动物的土地所有者有用。我们将开发的排名工具将能够评估拟议生境斑块(例如林地面积)对生物多样性的未来价值，从而加强在存在其他相互竞争的土地使用需求时收购和维护最佳地点的理由。

As the climate warms, all wild species will have to adjust or adapt if they are to survive. We know from studying climate change after previous ice ages, that species all over the temperate parts of the earth adapted by shifting their geographic ranges, following where the climate led them. We also have evidence that numerous species are shifting their ranges now, but most do not seem to be "keeping up" with the climate. The problem is that natural (or seminatural) habitat for the majority of species is now rare and highly fragmented compared to the era before agricultural intensification and industrialisation. When a species' habitat is restricted to a tiny fraction of the land area, it becomes very difficult for it to invade new territory at the cool edge of its range: it could easily get stuck in isolated fragments of habitat and eventually go extinct as the climate becomes unsuitable. This is a major stimulus for conservation organisations and governments to recreate and restore habitats in order to reconnect potentially isolated populations. However it is unrealistic to suppose we could restore the areas of some habitats to their prehistoric levels. For example, in the UK woodland used to be the dominant habitat. To provide effective conservation of biodiversity in the UK, we need to make informed decisions about (a) how much woodland is enough to preserve the majority of species and (b) how to target woodland creation where it will be most beneficial in allowing range shifting to occur. We also have to find a way of proceeding when we don't know all the factors that limit each species' distribution now (factors ranging from temperature and rainfall to interactions with other species), and cannot reliably predict the direction and distance they will need to shift. This piece of research will assist this decision-making by finding a general-purpose strategy for habitat creation that will work for most species in most landscapes. We will test a number of strategies - all in the form of a numerical rule for deciding, given an existing landscape, which land parcel to choose next for conversion. As examples of existing landscapes we will use real landscapes in the UK, with habitat information from our project partner Forest Research and from the satellite derived "Land Cover Map 2007". We will judge the strategies based on simulations of animal and plant species invading the landscape (assuming they start from a small population at any one edge). The variation in traits of our simulated species (e.g. habitat specialism, reproduction rate and dispersal ability) will be based on the variation observed across all species for which data exists. We hope that this will produce results that are representative of the whole community, rather than focussing just on a few well-studied species. We will also include genetic information in our simulations - genetic diversity is an important, and sometimes overlooked, aspect of biodiversity, and one which may be dramatically reduced as the population passes through habitat "bottlenecks" during range expansion.Based on the simulation results we will be able to rank the landscapes both in terms of the proportion of species that survive, and the proportion of genetic diversity that survives in these populations. Our results will be useful to planners and conservation organisations, but also to any land owners who are interested in creating habitat to benefit wildlife. The ranking tool we will develop will be able to estimate the future value of a proposed habitat patches (e.g. areas of woodland) to biodiversity, and therefore strengthen the case for acquiring and maintaining the best sites when there are other competing demands on land use.