QGIS调用SAGA生成河网与流域图层失败问题求助

问题现象 #

• 在QGIS 3.34.0中调用SAGA Next Gen的Channel Network and Drainage Basins工具从DEM提取流域时，弹出The following layers were not correctly generated错误
• 尝试将输出改为非临时文件、更换工作目录后问题仍未解决

核心错误原因 #

从执行日志可定位两个关键问题：

1. 版本不兼容：当前安装的SAGA版本为7.3.0，而该工具要求最低版本为9.1
2. 参数不匹配：QGIS向SAGA传递了SUBBASINS参数，但SAGA 7.3.0的该工具不支持此参数，导致命令执行失败

解决方案 #

方案1：升级SAGA到兼容版本 #

• 卸载现有SAGA 7.3.0版本
• 安装SAGA 9.1或更高版本（需确保与QGIS 3.34.0兼容）
• 重启QGIS后重新运行工具，此时SUBBASINS参数可被正确识别

方案2：使用替代工具（无需升级） #

若暂时无法升级SAGA，可选择以下兼容方案：

• 使用无Next Gen标识的旧版SAGAChannel Network and Drainage Basins工具
• 改用QGIS原生的Watershed工具（无需依赖SAGA）

完整错误日志 #

QGIS version: 3.34.0-Prizren
QGIS code revision: ffbdd678812
Qt version: 5.15.3
Python version: 3.10.12
GDAL version: 3.4.1
GEOS version: 3.10.2-CAPI-1.16.0
PROJ version: Rel. 8.2.1, January 1st, 2022
PDAL version: 2.3.0 (git-version: Release)
SAGA Next Gen version: 1.0.0
Algorithm started at: 2023-11-04T13:02:37
Algorithm 'Channel network and drainage basins' starting…
Input parameters:
{ 'BASIN' : 'TEMPORARY_OUTPUT', 'BASINS' : 'TEMPORARY_OUTPUT', 'CONNECTION' : 'TEMPORARY_OUTPUT', 'DEM' : '/tmp/processing_jFVHbY/c71f7863c5cd40b98a83e56596437892/TARGET_OUT_GRID.sdat', 'DIRECTION' : 'TEMPORARY_OUTPUT', 'NODES' : 'TEMPORARY_OUTPUT', 'ORDER' : 'TEMPORARY_OUTPUT', 'SEGMENTS' : 'TEMPORARY_OUTPUT', 'SUBBASINS' : True, 'THRESHOLD' : 5 }

Problem with SAGA installation: unsupported SAGA version (found: 7.3.0, required: >=9.1.).
ta_channels "5" -DEM "/tmp/processing_jFVHbY/35f004a1f92d49288c8836a5943964d4/TargetGrid.sgrd" -THRESHOLD 5 -SUBBASINS true -DIRECTION "/tmp/processing_jFVHbY/26054a9b76bc4e2694fd7c85891223af/DIRECTION.sdat" -CONNECTION "/tmp/processing_jFVHbY/8f09f4a88306449b81f7f0f244fe973f/CONNECTION.sdat" -ORDER "/tmp/processing_jFVHbY/4b99f7ff5a414954b4bb1b0e50766cba/ORDER.sdat" -BASIN "/tmp/processing_jFVHbY/69b59a2344fa4524b20cae335ceb4d19/BASIN.sdat" -SEGMENTS "/tmp/processing_jFVHbY/6a47017369c84ccfaa2f03f81c4e09cc/SEGMENTS.shp" -BASINS "/tmp/processing_jFVHbY/5813a16995c8486280959a1abffa86a7/BASINS.shp" -NODES "/tmp/processing_jFVHbY/63312dc8e86f405284e478ce48ce888b/NODES.shp"

SAGA Version: 7.3.0

Unknown option 'SUBBASINS'
____________________________
library path: /usr/lib/x86_64-linux-gnu/saga/
library name: libta_channels
library : ta_channels
tool : Channel Network and Drainage Basins
identifier : 5
author : O.Conrad (c) 2003
processors : 16 [16]
____________________________


Usage: saga_cmd ta_channels 5 [-DEM <str>] [-DIRECTION <str>] [-CONNECTION <str>] [-ORDER <str>] [-BASIN <str>] [-SEGMENTS <str>] [-BASINS <str>] [-NODES <str>] [-THRESHOLD <num>]
-DEM:<str> Elevation
Grid (input)
-DIRECTION:<str> Flow Direction
Grid (optional output)
-CONNECTION:<str> Flow Connectivity
Grid (optional output)
-ORDER:<str> Strahler Order
Grid (optional output)
-BASIN:<str> Drainage Basins
Grid (optional output)
-SEGMENTS:<str> Channels
Shapes (output)
-BASINS:<str> Drainage Basins
Shapes (output)
-NODES:<str> Junctions
Shapes (optional output)
-THRESHOLD:<num> Threshold
Integer
Minimum: 1
Default: 5
Execution completed in 0.19 seconds
Results:
{'BASIN': '/tmp/processing_jFVHbY/69b59a2344fa4524b20cae335ceb4d19/BASIN.sdat',
'BASINS': '/tmp/processing_jFVHbY/5813a16995c8486280959a1abffa86a7/BASINS.shp',
'CONNECTION': '/tmp/processing_jFVHbY/8f09f4a88306449b81f7f0f244fe973f/CONNECTION.sdat',
'DIRECTION': '/tmp/processing_jFVHbY/26054a9b76bc4e2694fd7c85891223af/DIRECTION.sdat',
'NODES': '/tmp/processing_jFVHbY/63312dc8e86f405284e478ce48ce888b/NODES.shp',
'ORDER': '/tmp/processing_jFVHbY/4b99f7ff5a414954b4bb1b0e50766cba/ORDER.sdat',
'SEGMENTS': '/tmp/processing_jFVHbY/6a47017369c84ccfaa2f03f81c4e09cc/SEGMENTS.shp'}

Loading resulting layers
The following layers were not correctly generated.
• /tmp/processing_jFVHbY/26054a9b76bc4e2694fd7c85891223af/DIRECTION.sdat
• /tmp/processing_jFVHbY/4b99f7ff5a414954b4bb1b0e50766cba/ORDER.sdat
• /tmp/processing_jFVHbY/5813a16995c8486280959a1abffa86a7/BASINS.shp
• /tmp/processing_jFVHbY/63312dc8e86f405284e478ce48ce888b/NODES.shp
• /tmp/processing_jFVHbY/69b59a2344fa4524b20cae335ceb4d19/BASIN.sdat
• /tmp/processing_jFVHbY/6a47017369c84ccfaa2f03f81c4e09cc/SEGMENTS.shp
• /tmp/processing_jFVHbY/8f09f4a88306449b81f7f0f244fe973f/CONNECTION.sdat
You can check the 'Log Messages Panel' in QGIS main window to find more information about the execution of the algorithm.

内容的提问来源于stack exchange，提问作者ASJ