Large woody debris survey between Tocumwal and Echuca 2024

The survey was undertaken via boat and has an extent of approximately 190kms. The survey involved counting all visible fallen trees and assigning each a condition, complexity, and orientation or aggregations of wood (>1m in length and 10cm in diameter) located below the high bank level (not floodplain). The information was captured using the field maps application on a mobile device and includes, photo(s), GPS locations, individual tree or aggregation of wood (>1m in length and 10cm in diameter), size scoring, complexity scoring and volume. Each score is in accordance with established state-wide assessments (Kitchingman et al. 2013). The survey was scheduled for completion once river flows fell below 8000ML/d at Yarrawonga Weir Method The survey will involve counting all visible fallen trees located within the regulated river channel between Tocumwal and Echuca. Timber that has fallen on the riverbank above the regulated flow height will only be included if it protrudes into the regulated river channel. Timber on the riverbank that lies above the regulated flow level and does not protrude into the channel will not be counted. This will predominantly occur in project zones 1 and 3 where the river is incised, and banks can be more than 10m high (see below). Living willows within the channel will not be counted as part of the survey (a separate methodology is required). All information will be captured using the field maps application on a mobile device. Information to be collected includes, photo(s), GPS locations, individual tree or aggregation of wood (>1m in length and 10cm in diameter), size scoring, complexity scoring, alignment and volume. Methodologies will be in accordance with established state-wide assessments (Kitchingman et al. 2013). Alignment methodology for in-stream woody habitat will be in accordance with NSW DPE (2015), Fish and Flows in the Northern Basin. The survey will be broken into three distinct project zones to enable the capture of data when river flows are conducive. 1) Tocumwal (ch1886) through to Kynmer regulator (VIC) (ch1850) 36kms This area will be surveyed once environmental flows cease and releases from Lake Mulwala are reduced to around 8,000ML/d. Survey to be scheduled late November/ December. 2) Kynmer regulator (ch1850) through to Barmah township (ch1762) 88kms This area will be surveyed when regulators into the forest are open, ideally there will be a small window when the regulators remain open and flows from Lake Mulwala are reduced. This survey will be scheduled in late October, early November (SCS will continue to liaise with the MDBA operators to ensure the most appropriate time can be selected). 3) Barmah township (ch1762) to Echuca-Moama Bridge (ch1713) 49kms This area will be surveyed once environmental flows cease and releases from Lake Mulwala are reduced to around 8,000ML/d. Survey to be scheduled late November/ December. One new question will be added to indicate if timber is partially within the channel, and two additional categories in the alignment methodology will be added to account for timber that has fallen in an upstream direction. An unknown category will be added to all questions in the survey to account for timber that cannot be accurately categorised. We anticipate the project will have a duration of 10 days and will be conducted in conjunction with a full bank condition assessment. This has provided considerable savings to the survey. All raw data files and notes will be compiled and provided to MDBA post the survey being completed本次调查采用乘船方式开展，作业范围约190公里。调查内容为统计所有可见的倒木，并为每一处倒木赋值状态、复杂度与朝向；同时统计高岸水位以下（非洪泛平原区域）长度大于1米、直径大于10厘米的木质堆积物。所有信息通过移动设备上的野外地图应用（Field Maps）采集，包含照片、GPS定位信息、单株倒木或木质堆积物（长度＞1m、直径＞10cm）、尺寸评分、复杂度评分与体积数据。各项评分均遵循已确立的全州评估标准（Kitchingman等人，2013）。本次调查计划在亚拉温加水坝（Yarrawonga Weir）的河道流量降至8000兆升/日以下时完成。 调查方法：本次调查将统计托库姆瓦尔（Tocumwal）至埃丘卡（Echuca）之间受控河道内所有可见的倒木。仅当河岸上的倒木突出于受控河道内时，才纳入统计；若倒木位于受控水位以上的河岸且未伸入河道，则不予统计。该情况主要出现在项目1区与3区，此处河道为下切型，河岸高度可达10米以上（详见下文）。河道内的活柳树不计入本次调查（需采用单独的调查方法）。所有信息均通过移动设备上的野外地图应用采集，需收集的内容包括照片、GPS定位信息、单株倒木或木质堆积物（长度＞1m、直径＞10cm）、尺寸评分、复杂度评分、朝向与体积数据。评估方法遵循已确立的全州评估标准（Kitchingman等人，2013）。河道内木质栖息地的朝向评估方法参照新南威尔士州规划与环境部（NSW DPE，2015）发布的《北流域鱼类与流量》报告。 本次调查将划分为3个独立的项目区块，以便在河道流量适宜时开展数据采集： 1. 托库姆瓦尔（河段编号ch1886）至金默调节器（维多利亚州，ch1850）：全长36公里。本次调查将在生态流量停止、马尔瓦拉湖（Lake Mulwala）泄流量降至约8000兆升/日时开展，计划于11月下旬至12月进行。 2. 金默调节器（ch1850）至巴马镇（ch1762）：全长88公里。本次调查将在林区河道调节器开启时开展，理想情况为调节器保持开启且马尔瓦拉湖泄流量降低的窗口期。计划于10月下旬、11月上旬开展（SCS将与墨累-达令盆地管理局（MDBA）运营方保持沟通，以选定最佳时段）。 3. 巴马镇（ch1762）至埃丘卡-莫伊马桥（ch1713）：全长49公里。本次调查将在生态流量停止、马尔瓦拉湖泄流量降至约8000兆升/日时开展，计划于11月下旬至12月进行。 本次调查将新增一个问题，用于标识木质堆积物是否部分位于河道内；同时在朝向评估方法中新增两个分类，以涵盖朝上游倒伏的木质堆积物。此外将为所有调查问题新增“未知”分类，用于处理无法准确归类的木质堆积物。 预计本次项目工期为10天，将与全面河岸状态评估同步开展，此举可大幅降低调查成本。所有原始数据文件与记录将在调查完成后汇总并提交给墨累-达令盆地管理局（MDBA）。