Predawn Leaf Water Potential of Oak-Hickory Forest at Missouri Ozark (MOFLUX) Site: 2004-2020

Measurements of predawn leaf water potential (PLWP) have been made at weekly to biweekly intervals during the 2004 to 2020 growing seasons of the second-growth upland oak-hickory forests at the Missouri Ozark AmeriFlux (MOFLUX) site. The MOFLUX site is located in the University of Missouri Baskett Wildlife Research area (BWREA), situated in the Ozark Border Region of central Missouri, USA. More recent data will be added periodically. This January 25, 2021 release appends data through October 16, 2020. There were no changes to the previously released data and the format and structure of this release are the same. Data citation title was updated to be inclusive of year 2020 data. In each year, except for 2004, the first measurements occurred in mid-May. In all years, the last measurements took place in late October. Leaf samples were collected weekly or biweekly before dawn from canopy and sapling individuals of the common tree species at the site. A total of 20–21 samples were obtained each day with 6–7 taken from white oak (Quercus alba L.), and the rest, with at least two samples per species, distributed among black oak (Q. velutina Lam.), sugar maple (Acer saccharum Marsh.), shagbark hickory (Carya ovata (Mill.) K. Koch), white ash (Fraxinus americana L.), and eastern redcedar (Juniperus virginiana L.), roughly in proportion to their relative stem abundance in the stand.本数据集针对美国密苏里奥索卡通量网（AmeriFlux）MOFLUX站点内的次生山地栎-山核桃林，于2004至2020年生长季期间以每周至每两周的间隔开展黎明前叶水势（predawn leaf water potential, PLWP）观测。 该MOFLUX站点坐落于美国密苏里州中部奥索卡边境区域的密苏里大学巴斯克特野生动物研究区（BWREA）内。 后续将定期增补最新观测数据。本次2021年1月25日发布的数据涵盖至2020年10月16日的观测结果；既往发布的数据集未作任何修订，本次发布的数据格式与结构与此前完全一致；数据引用标题已完成更新，以纳入2020年的观测数据。 除2004年外，其余年份的首次观测均始于5月中旬；所有年份的末次观测均在10月下旬完成。 观测于黎明前开展，针对站点内常见树种的冠层个体与幼树个体采集叶片样品，采样频率为每周或每两周一次。每日共采集20~21个样品，其中6~7个取自白栎（Quercus alba L.）；剩余样品按林分中各树种的相对茎干丰度比例分配，涵盖黑栎（Q. velutina Lam.）、糖枫（Acer saccharum Marsh.）、薄壳山核桃（Carya ovata (Mill.) K. Koch）、白蜡（Fraxinus americana L.）与东部红桧（Juniperus virginiana L.），且每个物种至少采集2个样品。