Collaborative Research: Climatic and Anthropogenic Forcing of Wetland Landscape Connectivity in the Great Plains

动物在景观中的存在和持久性取决于是否有合适的栖息地，以及单个动物找到这个栖息地的能力。因此，在任何景观中，动物都会遇到合适的栖息地斑块或垫脚石的排列，它们位于不合适的栖息地矩阵中。这些垫脚石的空间排列被称为“栖息地网络”。人类发展和气候变化造成的这些垫脚石的损失可能会改变这些栖息地网络，影响物种在面对快速气候和土地利用变化时的持久性。美国大平原的湿地栖息地嵌入了草原和农业的混合景观中。美国大平原的气候年复一年地发生着巨大的变化。气候驱动地表过程，如水文循环，而水文是控制湿地生境质量和湿地生境网络存在的最重要因素。因此，大平原湿地栖息地网络的空间布局在不断变化；一些湿地(垫脚石)随着其他湿地的重新出现而消失。土地用途的变化增加了额外的复杂性。越来越多的农民正在将大平原上剩余的草原转化为行作物，其中大部分转化发生在靠近湿地的地方。草原栖息地的丧失干扰了一些生物在邻近湿地之间移动的能力，而其他物种则倾向于避开没有足够草原覆盖的湿地。该奖项将使用大平原高度动态的湿地景观作为探索与栖息地连通性相关的一般原则的示范系统。特别是，这些资金将使私人投资机构能够研究气候变化和土地利用变化可能如何影响湿地栖息地网络的连通性，直至下个世纪。这项研究将集中在水鸟和两栖动物这两类模式生物上，它们在湿地之间传播的能力差异很大。量化栖息地连通性的方法将借鉴社会网络和被称为图论的数学分支的研究。来自卫星图像的湿地状况和土地利用趋势的时间序列、湿地水文学的计算机模拟和缩小尺度的气候变化预测将被用于：1)研究土地利用变化和气候变化对这两类动物在湿地之间分散的能力的影响；2)确定这些运动的障碍；3)确定在预测的变化下最有可能持续存在的湿地栖息地网络。结果将传播给公私合作伙伴关系，如美国内政部的景观保护合作社网络，以及由美国鱼类和野生动物服务机构领导的草原坑洞、雨水流域和普拉亚湖联合企业，以及州管理机构和非政府组织，如Ducks UnLimited和自然保护协会，以支持其湿地和草原地役权购买战略。该项目将支持四名共同执行主任在职业生涯早期和中期的发展，他们都来自任职人数不足的群体。通过支持外部培训和实验室交流，一个由四名博士后研究员和一名博士生组成的干部将接受跨学科、合作研究方面的培训。这项研究将通过利用其他不同学科的支持来推动大系统生物学领域的发展，例如高级水文建模、大气科学和图论，以解决以前无法解决的生物学问题。在该项目过程中开发的方法以及可能发现的一般原则，预计将广泛适用于全球其他类型栖息地网络的保护。

The presence and persistence of animals in a landscape is a function of the availability of suitable habitat and the ability of individual animals to find this habitat. Thus, in any landscape, animals encounter an arrangement of suitable habitat patches, or stepping-stones, located within a matrix of unsuitable habitat. The spatial arrangement of these stepping-stones is known as a "habitat network." Losses of these stepping-stones stemming from human development and climate change can alter these habitat networks, affecting persistence of the species in the face of rapid climate and landuse change. Wetland habitats in the U.S. Great Plains are embedded within a mixed grassland and agricultural landscape. The Great Plains experiences dramatic year-to-year variability in weather. Climate drives surface processes such as the hydrologic cycle, and hydrology is the most important factor controlling the quality of wetland habitats and the presence of wetland habitat networks. Thus the spatial arrangement of wetland habitat networks in the Great Plains is constantly changing; some wetlands (stepping stones) disappear as others reappear. Land use change adds an additional level of complexity. Increasingly, farmers are converting remnant grasslands in the Great Plains to row crops, with most of this conversion occurring in close proximity to wetlands. This loss of grassland habitat interferes with the ability of some organisms to move between neighboring wetlands, while other species tend to avoid wetlands not surrounded by sufficient grassland cover. This award will use the highly dynamic wetland landscapes in the Great Plains as model systems for exploring general principles related to habitat connectivity. In particular, the funds will allow the PIs to examine how both climate change and land use change will likely influence the connectivity of wetland habitat networks into the next century. This study will focus on two groups, water birds and amphibians, as model organisms that vary widely in their abilities to disperse between wetlands. Methods for quantifying habitat connectivity will be adapted from the study of social networks and a branch of mathematics known as graph theory. Temporal series of wetland condition and land use trends from satellite imagery, computer simulations of wetland hydrology, and downscaled climate change projections will be used to: 1) examine the effects of land use change and climate change on the ability of these two groups of animals to disperse between wetlands, 2) identify barriers to these movements, and 3) identify those wetland habitat networks most likely to persist under projected changeFindings from this study will be used in support of regional conservation planning. Results will be disseminated to public-private partnerships like the U.S. Department of Interior's network of Landscape Conservation Cooperatives and the Prairie Pothole, Rainwater Basin, and Playa Lakes Joint Ventures led by the U.S. Fish and Wildlife Service, and to state management agencies and nongovernmental organizations like Ducks Unlimited and The Nature Conservancy in support of their wetland and grassland easement purchasing strategies. This project will support the early- to mid-career development of four co-PIs, all of whom are from under-represented groups. Through support of external training and lab exchanges, a cadre of four Postdoctoral Fellows and one Ph.D. student will be trained in inter-disciplinary, collaborative research. This research will advance the field of Macrosystem Biology by leveraging support from other different disciplines, e.g., advanced hydrologic modeling, atmospheric science, and graph theory to address previously inaccessible biological questions. Methods developed over the course of this project, and general principles potentially discovered, are anticipated to be broadly applicable to conservation of other types of habitat networks, globally.