tailieunhanh - Estuarine Research, Monitoring, and Resource Protection - Chapter 4

Đại dương và Khí quyển Quốc gia (NOAA) Nghiên cứu các cửa sông Delaware quốc gia dự trữ (DNERR) là một cửa sông nghiên cứu quốc gia Hệ thống dự trữ (NERRS) trang web chương trình vào ngày 21 tháng 7 năm 1993. DNERR bao gồm hai trang web thành phần deÞned về 32 km (xem Hình ): 1. St thấp hơn Jones sông dự trữ trang web nằm ở phía nam của Dover eastcentral Kent County, Delaware 2. Blackbird Upper Creek dự trữ trang web nằm giữa Odessa và Smyrna ở miền nam New Castle County, Delaware Cả hai. | Case Study 3 Copyright 2004 CRC Press LLC 4 Delaware National Estuarine Research Reserve INTRODUCTION The National Oceanic and Atmospheric Administration NOAA designated the Delaware National Estuarine Research Reserve DNERR as a National Estuarine Research Reserve System NERRS program site on July 21 1993. The DNERR consists of two well-dehned component sites about 32 km apart see Figure 1. The Lower St. Jones River Reserve site located south of Dover in eastcentral Kent County Delaware 2. The Upper Blackbird Creek Reserve site located between Odessa and Smyrna in southern New Castle County Delaware Both the Lower St. Jones River Reserve site and the Upper Blackbird Creek Reserve site are subestuaries of the Delaware River estuary. Tidal marshes and tidal streams comprise the primary habitats of both reserve sites. The Lower St. Jones River Reserve site covers a 1518-ha area along the lower portion of the St. Jones River watershed. Here agricultural land use predominates in the watershed. The St. Jones River stretches for km across the Delmarva Peninsula and it discharges to the mid-Delaware Bay zone. The Trunk Ditch Beaver Branch and Cypress Branch are the largest tributaries of the Lower St. Jones River which is characterized by mesohaline salinity conditions. The lower boundary of the reserve site extends km into the open waters of Delaware Bay it encompasses a 1036-ha area of subtidal bottom. The Upper Blackbird Creek Reserve site which covers an area of 477 ha lies to km upstream of the Blackbird Creek mouth. This site is characterized by low salinity brackish or freshwater tidal creek habitat. Woodlots croplands and upland helds also occur within the designated boundaries of the reserve. Forested wetlands with coastal plain ponds blanket much of the land area upstream of the reserve site notably in the Blackbird State Forest. Forested and agricultural land cover dominates much of the Blackbird Creek watershed. Extensive tidal mud