FSML: Improved research infrastructure to monitor ecosystem dynamics under ongoing climate change at the La Selva Research Station, Costa Rica

在过去十年中，热带研究组织（OTS）拥有和经营的位于哥斯达黎加的一个低地潮湿热带森林-拉塞尔瓦林冠塔网络（La Selva Canopy Tower Network）-这是一个五塔林冠接入系统，配备了电力、光纤连接和无线网络连接以及一系列气象和地球物理传感器-为拉塞尔瓦研究站（http：//www.ots.ac.cr/）的广泛研究提供了支持。La Selva对森林动态和气体交换的研究，其中大部分是利用这些树冠塔进行的，在帮助了解气候变化条件下热带森林碳动态的重要性方面发挥了领导作用。La Selva林冠塔网络是热带雨林综合通量监测的理想场所，因为它已被深入研究，长期数据集记录了生态和生态系统动态，以及广泛的正在进行和计划中的研究项目。根据该合同部署的第二代塔网络将提供关于生态系统通量的连续数据以及同时详细的冠层和土壤环境条件，这些数据对于广泛的数据分析，合成和建模工作具有重要价值。这些塔已经为研究生和本科生提供了一个宝贵的体验式学习平台。每年，La Selva都会举办超过10，000天的学生参观车站。OTS课程带来了大约150名本科生和150名研究生到拉塞尔瓦学习如何进行自己的研究。OTS教育计划的一个重要组成部分是强调招收和提升在STEM学科中代表性不足的学生。在过去的五年中，OTS教育项目中24%的美国本科生来自STEM学科中代表性不足的群体。此外，每年有来自美国、欧洲和哥斯达黎加的120多个学院领导的学术团体访问该站。一些课程，特别是OTS开设的课程，鼓励学生使用塔及其传感器进行短期项目。OTS还为本科生提供暑期研究体验，其中80%以上是少数民族学生。这些学生将在空间站度过10周，并有机会使用塔网络进行夏季研究。最近，树冠塔网络因树木倒塌而受到挫折，影响了三座塔的功能。OTS正在拆除和重建倒塌的塔楼。虽然具有破坏性，但这一事故也提供了一个机会，可以解决以前系统的局限性，重建树冠塔和传感器网络，以创建最先进的生态系统通量和生物气象学（biomet）监测系统，可以显着扩大塔网络的研究机会。此外，重新设计塔楼走道和安装更新的安全设备将使新的天篷塔楼网络更加安全，不易受到未来中断的影响。具体而言，随着三个受损塔的复活，我们建议开发第二代冠层塔系统，增加以下通量-生物网仪器和安全功能：（1）涡度相关系统，包括声波风速计，CO2-H2O分析仪和冠层CO2-H2O剖面系统，以连续测量生态系统的碳，水和能量通量;（2）用于连续测量冠层空气湿度和温度的冠层监测传感器，包括四分量净辐射计和PAR传感器;（3）用于连续测量土壤CO2和O2浓度、湿度和温度的土壤监测传感器;（4）增设塔节，将两塔的高度提高到50米（该地区最高树冠树木的高度）;（5）加建树冠中段行人通道，以增加通往新树冠层的通道;（6）增加安全设施，包括可拆卸螺栓和锚栓;以及（7）改进WiFi和光纤系统的连通性，以提高数据收集和管理的远程可操作性。新的通量-生物网监测系统与改进和更强大的塔基础设施相结合，从而为La Selva的研究设施提供了综合升级，这将广泛用于热带生态学和生态系统科学的现有和新的研究计划。这些塔还将大大扩展培训体验，并提高美国和拉丁美洲学生使用塔的安全性。

For the past decade, the La Selva Canopy Tower Network, a five-tower canopy-access system equipped with electricity, connectivity through fiber-optics and WiFi connection, and a range of meteorological and biogeophysical sensors, has supported a wide range of research at La Selva Research Station (http://www.ots.ac.cr/), a lowland wet tropical forest in Costa Rica owned and operated by the Organization for Tropical Studies (OTS). La Selva research on forest dynamics and gas exchange, much of which has been carried out using these canopy towers, has played a leadership role in helping understand the significance of carbon dynamics in tropical forests under changing climatic conditions. The La Selva Canopy Tower Network is an ideal site for integrated flux monitoring of a tropical rainforest, given that is has been intensively studied with long-term datasets documenting ecological and ecosystem dynamics, and a wide range of ongoing and planned research projects using the towers. The second-generation tower network to be deployed under this award will provide continuous data on ecosystem fluxes and concurrent detailed canopy and soil environmental conditions valuable for a broad range of data analysis, synthesis, and modelling efforts. These towers already provide a valuable platform for experiential learning for both graduate and undergraduate students. Each year, La Selva hosts more than 10,000 days of student visitation to the station. OTS courses bring approximately 150 undergraduates and 150 graduate students to La Selva to learn how to conduct their own research. An important component of the OTS education programs is its emphasis on recruiting and advancing students underrepresented in the STEM disciplines. Over the last five years, 24% of all U.S. undergraduates in the OTS education programs are from under-represented groups in the STEM disciplines. Additionally, more than 120 faculty-led academic groups from the US, Europe, and Costa Rica visit the station each year. Some courses, especially those run by OTS, encourage students to conduct short-term projects using the towers and their sensors. OTS also runs summer Research Experiences for Undergraduates comprised of more than 80% minority students. These students spend 10 weeks at the station and have the opportunity to conduct their summer research using the tower network.The canopy tower network had a recent setback caused by a treefall that affected the functionality of three towers. OTS is in the process of dismantling and re-establishing the fallen towers. While disruptive, this accident has also presented an opportunity to address the limitations of the previous system and rebuild the network of canopy towers and sensors to create a state-of-the-art ecosystem flux and bio-meteorology (biomet) monitoring system that can significantly expand the research opportunities of the tower network. In addition, a redesign of the tower walkway and installation of updated safety equipment will allow the new canopy tower network to be safer and less vulnerable to future disruptions. Specifically, as the three damaged towers are resurrected, we propose to develop a second-generation canopy tower system by adding the following flux-biomet instrumentation and safety features: (1) Eddy covariance system including a sonic anemometer, CO2-H2O analyzer, and canopy CO2-H2O profile system in order to continuously measure ecosystem fluxes of carbon, water and energy; (2) Canopy monitoring sensors for continuous measurements of canopy air humidity and temperature including four component net radiometers and PAR sensors; (3) Soil monitoring sensors for continuous measurements of soil CO2 and O2 concentration, moisture, and temperature; (4) Additional tower section to increase the height of two the tower to 50 meters (the height of the tallest canopy trees in the area); (5) Addition of mid-canopy walkway to increase access to new canopy levels; (6) Additional safety features including break-away bolts and anchors; and (7) Improved connectivity in WiFi and fiber-optic systems to increase the remote-operability of data collection and management. The new flux-biomet monitoring system combined with the improved and more robust tower infrastructure thus provide an integrated upgrade in the facilities for research at La Selva that will have broad use for existing and new research programs in tropical ecology and ecosystem science. The towers will also significantly expand the training experience and increase the safety of US and Latin American students using the towers.