Marine Corps Base Camp Lejeune Onslow Beach Sidescan

Critical military training and testing on lands along the nation’s coastal and estuarine shorelines are increasingly placed at risk because of development pressures in surrounding areas, impairments due to other anthropogenic disturbances, and increasing requirements for compliance with environmental regulations. The U.S. Department of Defense (DoD) intends to enhance and sustain its training and testing assets and to optimize its stewardship of natural resources through the development and application of an ecosystem-based management approach on DoD installations. To accomplish this goal, particularly for installations in estuarine/coastal environments, the Strategic Environmental Research and Development Program (SERDP) launched the Defense Coastal/Estuarine Research Program (DCERP) as a minimum 10-year effort at Marine Corps Base Camp Lejeune (MCBCL) in North Carolina. The results of the first six years of the program (DCERP1) are presented here.The overarching objectives of DCERP are to: (1) understand the effects of military training activities, infrastructure development, and other coastal military installations; (2) develop models, tools, and indicators to evaluate ecosystem health; and (3) recommend adaptive management strategies to sustain ecosystem natural resources within the context of an active military installation.Sidescan data are from the shallow (-2 to -11.5m, NAVD88) nearshore region of Onslow Beach. Data were collected in 2007 using a high-resolution (234 kHz) Sea Swath Plus Interferometric swath bathymetric profiler with co-registered side-scan sonar. Line spacing ranged from 25-75m to allow for nearly complete coverage of the seafloor, minimizing data holidays. The position of each data point was related to NAD83 using RTK-GPS. Vessel heave, pitch, and roll were corrected in real-time using an IXSEA Octans motion sensor. Amplitude data were extracted as backscatter values from the bathymetric files and processed using Chesapeake Technology SonarWiz MAP5. Geotif images were generated using SonarWiz MAP5. In order to keep the file size manageable, two geotiff images were created for the data.

美国沿海及河口岸线区域的重要军事训练与测试活动正日益面临风险，原因包括周边地区的开发压力、其他人为干扰造成的生态损害，以及遵守环境法规的要求不断提高。美国国防部（DoD）旨在通过在其设施上开发和应用基于生态系统的管理方法，增强并维持其训练与测试资产，优化自然资源管理。为实现这一目标，特别是针对河口/沿海环境中的设施，战略环境研究与发展计划（SERDP）在北卡罗来纳州的勒琼海军陆战队基地（MCBCL）启动了国防沿海/河口研究计划（DCERP），该计划至少持续10年。

DCERP的总体目标包括：（1）了解军事训练活动、基础设施建设及其他沿海军事设施的影响；（2）开发用于评估生态系统健康的模型、工具和指标；（3）提出适应性管理策略，以在现役军事设施背景下维持生态系统自然资源。

侧扫声呐数据来自昂斯洛海滩（Onslow Beach）的浅水区（NAVD88基准下-2至-11.5米）。数据于2007年采集，使用高分辨率（234 kHz）Sea Swath Plus干涉式条带测深仪及共配准侧扫声呐。测线间距为25-75米，以实现近乎完整的海底覆盖，减少数据空缺。每个数据点的位置通过实时动态全球定位系统（RTK-GPS）与北美大地坐标系1983（NAD83）关联。使用IXSEA Octans运动传感器实时校正船体的升沉、俯仰和横滚。从测深文件中提取振幅数据作为反向散射值，并使用切萨皮克技术公司的SonarWiz MAP5软件进行处理。GeoTIFF图像通过SonarWiz MAP5生成。为控制文件大小，数据被分为两幅GeoTIFF图像。