Suspended particulate organic matter composition of three marsh ponds in PIE-LTER (Rowley, MA) from 2014.

<p>The three ponds are located in the high marsh (1.43-1.46 m above North American Vertical Datum of 1988) of the Plum Island Ecosystems – Long Term Ecological Research (PIE-LTER) site. Suspended POM in pond surface waters was collected weekly in 1 L combusted glass bottles and filtered through combusted glass fiber filters (June 25-August 13, November 11-25, 2014) and analyzed for TOC, TN, δ¹³C, and δ¹⁵N. All samples were frozen (-20 ℃) until analysis. Samples were prepared for elemental and isotopic analyses by drying to constant mass (60 °C) and fuming with hydrochloric (HCl) acid to remove carbonates (Hedges and Stern 1984). Analyses were performed by the Stable Isotope Laboratory at the Marine Biological Laboratory (Woods Hole, MA). Isotopic data are reported in the conventional δ-notation in units of per mil (‰).</p>三处池塘位于普拉姆岛生态系统-长期生态研究（Plum Island Ecosystems – Long Term Ecological Research, PIE-LTER）站点的高潮汐滩，其高程高于1988年北美垂直基准面（North American Vertical Datum of 1988）1.43~1.46米。本研究于2014年6月25日至8月13日、11月11日至25日期间，每周使用1升经灼烧处理的玻璃瓶采集池塘表层水体中的悬浮颗粒有机物（Particulate Organic Matter, POM），经灼烧玻璃纤维滤膜过滤后，针对总有机碳（Total Organic Carbon, TOC）、总氮（Total Nitrogen, TN）、碳同位素δ¹³C及氮同位素δ¹⁵N开展分析。所有样品均保存于-20℃冷冻环境直至上机分析。样品前处理采用60℃烘干至恒重、盐酸（HCl）熏蒸脱除碳酸盐的方法（Hedges与Stern, 1984），以满足元素与同位素分析要求。同位素分析工作由美国马萨诸塞州伍兹霍尔海洋生物实验室（Marine Biological Laboratory）稳定同位素实验室完成。同位素数据采用常规δ符号表示，单位为千分比（‰）。