Erosion processes in degraded argan-tree populations in South Morocco

摩洛哥南部退化的摩洛哥坚果树种群的侵蚀过程

• 批准号: 388485989
• 负责人: Dr. Irene Marzolff
• 金额: --
• 依托单位: Institut für Physische Geographie (IPG)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/388485989?language=en
• 关键词: Erosion; processes; degraded; argan; tree

Soil and vegetation in the endemic argan-tree population in Morocco is increasingly being degraded by expansion and intensifying agriculture as well as overgrazing. Areas with canopy cover decrease while areas without cover between the argan trees increase. Due to reduced infiltration, runoff and soil erosion rates rise drastically. Thus, it is more difficult for young stands to establish themselves on these degraded soils, and undergrowth remains patchy. We will study argan-tree populations in different stages of degradation to establish threshold values to describe the initiation as well as the dynamisation of erosion processes, especially rill and gully erosion. In three study areas in the High Atlas and the Anti-Atlas, fenced-in reforestation areas will be compared to unprotected areas on differing slopes. The development of population densities will be quantified with high-resolution CORONA satellite photographs from 1968 and large-scale aerial photographs from 2017/18 that will be taken during the project using unmanned aerial vehicles (UAV). Characteristic tree crowns will be documented and classified using structure from motion (SfM)-techniques (3D models derived from multicopter images). Analyses of grain sizes, aggregate stability, soil organic matter and soil nutrients will show the decreasing influence of the crown covered area, with an increasing distance between trees, on an expanding intertree area. The erodibility and the infiltration capacity of the intertree areas in different stages of degradation will be studied using infiltration measurements and rainfall simulation experiments. Volumes of linear erosion forms will be quantified using SfM-monitoring with 3D-modelling. Stone cover and cattle trails can be identified from the UAV photographs. Cattle counts as well as interviews with key informants will complement the knowledge of the grazing pressure by sheep and goats on the areas with argan-tree populations. By studying the degradation of population densities, intertree and tree areas, the argan-tree populations can be classified into stability classes defined by values acquired through this multi-method-concept. The threshold values describe the dynamisation of erosion processes under argan trees and prove that certain erosion processes correlate with certain degradation states or population densities. This is the vital prerequisite for a sustainable cultivation of the argan-tree populations.

摩洛哥特有的阿甘树种群的土壤和植被由于农业的扩张和强化以及过度放牧而日益退化。有树冠覆盖的地区减少，而没有覆盖的地区之间的阿甘树增加。由于渗透减少，径流和土壤侵蚀率急剧上升。因此，幼林更难在这些退化的土壤上立足，林下植被仍然是零星的。我们将研究阿甘树种群在不同阶段的退化，以建立阈值来描述的启动以及动态的侵蚀过程，特别是细沟和沟壑侵蚀。在High Atlas和Anti-Atlas的三个研究地区，将把围栏内的重新造林地区与不同斜坡上未受保护的地区进行比较。人口密度的发展将通过1968年的高分辨率CORONA卫星照片和2017/18年的大型航空照片进行量化，这些照片将在项目期间使用无人机（UAV）拍摄。将使用运动结构（SfM）技术（来自多旋翼图像的3D模型）记录和分类特征树冠。对粒径、团聚体稳定性、土壤有机质和土壤养分的分析表明，随着树间距离的增加，树冠覆盖面积对树间面积的影响逐渐减小。将利用入渗测量和降雨模拟试验研究不同退化阶段的林间地区的可蚀性和入渗能力。线性侵蚀形式的破坏将使用SfM监测和3D建模进行量化。从无人机拍摄的照片中可以识别出石头覆盖物和牛迹。牛的数量以及与关键线人的访谈将补充绵羊和山羊对阿甘树种群地区的放牧压力的知识。通过研究种群密度、树间和树面积的退化，可以将阿甘树种群划分为由通过这种多方法概念获得的值定义的稳定类。阈值描述了阿甘树下的侵蚀过程的动态化，并证明某些侵蚀过程与某些退化状态或人口密度相关。这是阿甘树种群可持续种植的重要先决条件。

项目成果

Geomorphodynamics in Argan Woodlands, South Morocco

• DOI: 10.3390/w11102193
• 发表时间: 2019-10
• 期刊: Water
• 影响因子: 3.4
• 作者: Mario Kirchhoff;L. Engelmann;L. Zimmermann;M. Seeger;I. Marzolff;Ali Aït Hssaine;J. Ries

Soil Degradation in Argan Woodlands, South Morocco

摩洛哥南部阿甘林地的土壤退化

• DOI: 10.5194/egusphere-egu2020-11249
• 发表时间: 2020
• 作者: Kirchhoff;Engelmann;Zimmermann;Marzolff;Seeger;Aït Hssaine
• 通讯作者: Aït Hssaine

Relative quantification of wind erosion in argan woodlands in the Souss Basin, Morocco

• DOI: 10.1002/esp.5002
• 发表时间: 2020-09
• 期刊: Earth Surface Processes and Landforms
• 影响因子: 3.3
• 作者: M. Marzen;Mario Kirchhoff;I. Marzolff;Ali Aït Hssaine;J. Ries

Land use in the Souss region, South Morocco and its influence on wadi dynamics

摩洛哥南部苏斯地区的土地利用及其对河道动态的影响

• DOI: 10.1127/zfg_suppl/2019/0525
• 发表时间: 2019
• 期刊: Zeitschrift für Geomorphologie, Supplementary Issues
• 作者: Kirchhoff;Aït Hssaine
• 通讯作者: Aït Hssaine

Spatial distribution of argan tree influence on soil properties in southern Morocco

• DOI: 10.5194/soil-7-511-2021
• 发表时间: 2021-08
• 期刊: SOIL
• 影响因子: 6.8
• 作者: Mario Kirchhoff;Tobias Romes;I. Marzolff;M. Seeger;Ali Aït Hssaine;J. Ries