Mid-19th Century Land Use on the Southern New England and New York Coasts 1832-1886

The widespread influence of land use and natural disturbance on population, community, and landscape dynamics and the long-term legacy of disturbance on modern ecosystems requires that a historical, broad-scale perspective become an integral part of modern ecological studies and conservation assessment and planning. In previous studies, the Harvard Forest Long Term Ecological Research (LTER) program has developed an integrated approach of paleoecological and historical reconstruction, meteorological modeling, air photo interpretation, GIS analyses, and field studies of vegetation and soils, to address fundamental ecological questions concerning the rates, direction, and causes of vegetation change, to evaluate controls over modern species and community distributions and landscape patterns, and to provide critical background for conservation and restoration planning. In the current study, we extend this approach to investigate the link between landscape history and the abundance, distribution, and dynamics of species, communities and landscapes of the Cape Cod to Long Island coastal region, including the islands of Martha's Vineyard, Nantucket, and Block Island. The study region includes many areas of high conservation priority that are linked geographically, historically, and ecologically. This data package includes GIS layers digitized by Harvard Forest researchers from copies of the US Coastal Survey “T-Sheet” maps available from the National Archives in College Park, Maryland. The US Coastal Survey, and then the US Coast and Geodetic Survey mapped the region, or specific parts of it, several times between 1832 and the 1960s. In this project we digitized the earliest T-Sheet available for each location. The original maps were surveyed between 1832 and 1886, with most of them made between 1835 to 1855. The original maps showed features such as roads, farm walls, railroads, buildings, some industrial buildings, saltworks, wharfs, and land cover including woodlands, sandplains, grasslands, open agricultural fields, cultivated areas, fruit tree orchards, wetlands, etc. Many sheets had symbols which differentiated conifer trees from hardwoods. There were some inconsistencies in what features were mapped or how they were drawn between the original T-Sheets. Since we digitized the maps over the course of several different research projects, we did not always digitize all of the same features in each geographic area, therefore users of this data are encouraged to look at scans of the original T-Sheets for their specific areas of interest (links below). We always digitized land cover and roads and occasionally buildings and fences as mentioned in the datasets below.土地利用与自然干扰对种群、群落及景观动态的广泛影响，以及干扰对现代生态系统的长期遗留效应，要求将历史、大尺度视角纳入现代生态学研究、保护评估与规划的核心组成部分。过往研究中，哈佛森林长期生态学研究（Long Term Ecological Research, LTER）项目已发展出一套整合古生态学与历史重建、气象建模、航空照片解译、地理信息系统（GIS）分析以及植被与土壤野外调查的研究方法，用以解答植被变化的速率、方向与成因等核心生态学问题，评估现代物种与群落分布及景观格局的调控机制，并为保护与修复规划提供关键背景支撑。本研究将此方法拓展至科德角至长岛沿海区域（包括玛莎葡萄园岛、楠塔基特岛与布洛克岛），旨在探究景观历史与该区域物种、群落及景观的丰度、分布与动态之间的关联。该研究区域包含诸多具有高度保护优先级的区域，这些区域在地理、历史与生态学层面均存在关联。本数据包包含哈佛森林研究人员从马里兰州学院公园国家档案馆获取的美国海岸测量局（US Coastal Survey）"T-Sheet"地图副本中数字化得到的GIS图层。美国海岸测量局及其后的美国海岸与大地测量局，于1832年至20世纪60年代期间多次对该区域及其部分区域开展测绘工作。本项目中，我们对每个点位可获取的最早"T-Sheet"地图进行了数字化处理。原始测绘地图的测绘时间介于1832年至1886年之间，其中大部分完成于1835年至1855年。原始地图标注了道路、农场围墙、铁路、建筑、部分工业建筑、盐场、码头等要素，以及林地、砂质平原、草原、开阔农田、耕作区、果园、湿地等土地覆盖类型。多数图幅配有区分针叶树与阔叶树的符号。不同原始"T-Sheet"地图之间，在测绘要素类型与绘制方式上存在部分不一致之处。由于我们在多个不同研究项目中分批完成了地图数字化工作，并非所有地理区域均完整数字化了全部要素，因此本数据的使用者可查阅下方链接中对应研究区域的原始"T-Sheet"地图扫描件。如下数据集所述，我们始终对土地覆盖类型与道路进行了数字化处理，部分情况下也会包含建筑与围栏要素。