Among the 63 U.S. national parks , few are as defined by a single river’s floodplain as Congaree National Park in South Carolina. While the features are also prominent in other parks , a full 80 percent of Congaree National Park lies within the Congaree River floodplain.
在美国 63 个国家公园中，很少有国家公园像南卡罗来纳州的康加里国家公园一样由单一河流的洪泛区定义。虽然这些特征在其他公园中也很突出，但康加里国家公园 80% 的面积都位于康加里河漫滩内。
It’s a place home to one of the largest intact tracts of old-growth bottomland hardwood forests in the United States. In this image captured by the OLI (Operational Land Imager) on Landsat 9 , the river winds through the forested plain, along with curving bands of green that trace old channels, ridges, and swales left behind as the river gradually migrated across it. Slight differences in elevation in these paleochannels and other landforms affect how frequently they flood, producing distinct ecosystems that appear in contrasting shades of green.
这里拥有美国最大的完整原始低地硬木森林之一。在 Landsat 9 上的 OLI（操作陆地成像仪）拍摄的这张图像中，河流蜿蜒穿过森林覆盖的平原，沿着河流逐渐迁移穿过它时留下的古老河道、山脊和洼地的弯曲绿色带。这些古河道和其他地貌的海拔细微差异会影响它们洪水的频率，从而产生呈现出对比鲜明的绿色色调的独特生态系统。
The river flows through flat, soft terrain, which encourages the formation of bends and meanders . Water typically flows faster on the outside of bends, leading to more rapid erosion as the channel carves into the outer riverbank. It moves more slowly on the inside of bends, resulting in the deposition of sediment and the growth of sandy features called point bars . Over time, this process can cut off a bend from the main river channel, forming U-shaped oxbow lakes .
河流流经平坦、松软的地形，这有利于形成弯曲和曲流。水流通常在弯道外侧流动得更快，当河道切入外河岸时，会导致更快的侵蚀。它在弯曲内侧移动得更慢，导致沉积物沉积和称为点坝的沙质特征的生长。随着时间的推移，这个过程会切断主河道的一个弯道，形成U形的牛轭湖。
The National Park Service lists Weston Lake, 1.2 miles (1.9 kilometers) from the visitor center, as one of the park’s most permanent oxbow lakes, noting that it is relatively deep and lacks the shallow clay and silt layer found in most of the park’s other oxbow lakes, such as Devil’s Elbow . On the right side of the image is Bates Old River, a roughly 4-mile-long abandoned channel of the Congaree River and one of the longest oxbow lakes in South Carolina. Over time, abandoned channels and oxbow lakes can fill with sediment and become shallow wetlands. Some of these low-lying, water-filled features are known as sloughs , where flood-tolerant cypress-tupelo forests tend to grow.
国家公园管理局将距离游客中心 1.2 英里（1.9 公里）的韦斯顿湖 (Weston Lake) 列为公园内最永久的牛轭湖之一，并指出该湖相对较深，并且缺乏公园内大多数其他牛轭湖（例如魔鬼肘湖）所具有的浅粘土和淤泥层。图片右侧是贝茨旧河 (Bates Old River)，这是康加里河 (Congaree River) 上一条约 4 英里长的废弃河道，也是南卡罗来纳州最长的牛轭湖之一。随着时间的推移，废弃的河道和牛轭湖会充满沉积物，变成浅湿地。其中一些低洼、充满水的地貌被称为沼泽，那里往往生长着耐洪的柏树-图珀洛森林。
While loggers targeted forests along the Congaree in the 1880s, challenges such as frequent flooding, interminably muddy roads, and mosquito-plagued conditions meant that most of the floodplain forests escaped the widespread logging that transformed other parts of the Southeast. By the 1950s, conservationists had begun to recognize how rare old-growth forests of this type had become in the region. Congress designated the area a national monument in 1976, and it became a national park in 2003.
1880 年代，伐木者以康加里河沿岸的森林为目标，但频繁的洪水、泥泞的道路和蚊虫肆虐的环境等挑战意味着，大部分洪泛区森林都躲过了大范围的砍伐，而这种砍伐改变了东南部其他地区的情况。到 20 世纪 50 年代，自然资源保护主义者开始认识到该地区这种类型的原始森林已变得多么稀有。国会于 1976 年将该地区指定为国家纪念碑，并于 2003 年成为国家公园。
As the river snakes its way through the park’s mostly flat terrain, it overflows its banks several times per year, usually in the winter and early spring but also in the summer and fall after hurricanes and major rainstorms. These floods distribute broad layers of nutrient-rich silt throughout the floodplain, nourishing the forests and contributing to the high concentration of unusually large trees in the park.
由于河流蜿蜒穿过公园大部分平坦的地形，因此每年都会多次溢出河岸，通常是在冬季和早春，但也会在飓风和大暴雨过后的夏季和秋季发生。这些洪水在整个洪泛区散布了大片营养丰富的淤泥，滋养了森林，并导致公园内异常高大的树木高度集中。
Over the decades, Congaree National Park has harbored a remarkable array of giant “champion” trees that have held national and state size records for their species. Though individual trees have gained and lost champion status as they have been damaged, have died, or been surpassed by newly measured trees elsewhere, Congaree trees such as the possumhaw ( Ilex decidua ), water hickory ( Carya aquatica) , loblolly pine ( Pinus taeda ), laurel oak ( Quercus laurifolia ), swamp tupelo ( Nyssa biflora ), and sweetgum ( Liquidambar styraciflua ) have held records at times.
几十年来，康加里国家公园拥有一系列引人注目的巨型“冠军”树木，这些树木保持着国家和州树种大小的记录。虽然个别树木因受损、死亡或被其他地方新测量的树木超越而获得或失去了冠军地位，但Congaree树如负鼠（Ilex decidua）、水山核桃（Carya Aquatica）、火炬松（Pinus taeda）、月桂橡（Quercus laurifolia）、沼泽图珀洛（Nyssa biflora）和枫香（Liquitambar） styraciflua ）曾多次保持记录。
During this National Park Week , celebrate by exploring Earth Observatory’s U.S. National Parks from Space collection . You can also check out the offerings of Earth to Sky , a collaborative program that connects NASA science with park service rangers across the nation.
在这个国家公园周期间，通过探索地球观测站的太空美国国家公园收藏来庆祝。您还可以查看 Earth to Sky 的产品，这是一个将 NASA 科学与全国各地的公园服务护林员联系起来的合作项目。
NASA Earth Observatory image by Michala Garrison, using Landsat data from the U.S. Geological Survey . Story by Adam Voiland.
NASA 地球观测站图像，由 Michala Garrison 拍摄，使用美国地质调查局的陆地卫星数据。亚当·沃伊兰的故事。