2005-004-FA_SAMPLES.SHP: Sediment sample and textural properties at 40 sample locations collected by the U.S. Geological Survey in Moultonborough Bay, Lake Winnipesaukee, New Hampshire in 2005 (Geographic, WGS 84, Esri point shapefile)

In freshwater bodies of New Hampshire, the most problematic aquatic invasive plant species is Myriophyllum heterophyllum or variable leaf water-milfoil. Once established, variable leaf water-milfoil forms dense beds that can alter the limnologic characteristics of a waterbody, impacting natural lacustrine communities and their habitats. Variable leaf water-milfoil infestations also disrupt recreational uses of waterbodies and have negatively affected swimming, boating, fishing, and property values in and around several lakes and ponds in New Hampshire. In 1965, Moultonborough Bay, Lake Winnipesaukee became the first waterbody in New Hampshire where variable leaf water-milfoil was observed. Variable leaf water-milfoil is native to the Southeastern and Midwestern areas of the United States where more alkaline waters appear to limit the growth of this plant. Outside its native range, however, it adapts well to the relatively acidic, low-alkalinity, and nutrient-poor conditions of oligotrophic lakes and bays similar to Moultonborough Bay. In 2005, the New Hampshire Department of Environmental Services (NHDES) collaborated with the U.S. Geological Survey to investigate the distribution (presence and density) of variable leaf water-milfoil in Moultonborough Bay. This study utilized geophysical systems and conventional water-quality measurements to identify lake-floor environments that may provide suitable habitat for the establishment and growth of variable leaf water-milfoil. The results of the study are intended to assist resource managers in federal and state agencies by providing methods for detecting variable leaf water-milfoil and for identifying areas susceptible to infestation. Ultimately, this information may lead to early detection, prevention, and more effective mitigation strategies.在美国新罕布什尔州的淡水水体中，危害最为严重的水生入侵植物物种为异叶狐尾藻（Myriophyllum heterophyllum，variable leaf water-milfoil）。该物种一旦成功定殖，便会形成密集的水生草床，可改变水体的湖沼学特征，进而干扰自然淡水湖泊群落及其栖息生境。异叶狐尾藻的入侵还会破坏水体的休闲使用功能，对新罕布什尔州多座湖泊及周边池塘的游泳、划船、垂钓活动以及区域地产价值均造成了负面影响。 1965年，温尼佩绍基湖（Lake Winnipesaukee）的莫尔顿伯勒湾（Moultonborough Bay）成为新罕布什尔州首个发现异叶狐尾藻的淡水水体。该物种原产于美国东南部与中西部地区，在其原生分布区内，较高的水体碱度似乎会抑制其生长。而在原生分布范围之外，它能够很好地适应寡营养湖泊及海湾（如莫尔顿伯勒湾）相对酸性、低碱度且营养匮乏的生境条件。 2005年，新罕布什尔州环境服务部（New Hampshire Department of Environmental Services, NHDES）与美国地质调查局（U.S. Geological Survey）合作，针对莫尔顿伯勒湾内异叶狐尾藻的分布情况（包括存在范围与种群密度）开展了调查研究。本研究借助地球物理探测系统与常规水质测量手段，识别出可能适宜异叶狐尾藻定殖与生长的湖底环境。该研究成果旨在为联邦及州级机构的资源管理者提供检测异叶狐尾藻以及甄别易受入侵区域的方法，以辅助其开展管理工作。最终，这些研究信息有望助力实现早期入侵检测、预防管控，并制定更为高效的入侵缓解治理策略。