This page has only limited features, please log in for full access.
Non-forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, and are highly sensitive to climatic changes. Yet these ecosystems are poorly represented in remotely sensed biomass products and are undersampled by in situ monitoring. Current global change threats emphasize the need for new tools to capture biomass change in non-forest ecosystems at appropriate scales. Here we developed and deployed a new protocol for photogrammetric height using unoccupied aerial vehicle (UAV) images to test its capability for delivering standardized measurements of biomass across a globally distributed field experiment. We assessed whether canopy height inferred from UAV photogrammetry allows the prediction of aboveground biomass (AGB) across low-stature plant species by conducting 38 photogrammetric surveys over 741 harvested plots to sample 50 species. We found mean canopy height was strongly predictive of AGB across species, with a median adjusted R2 of 0.87 (ranging from 0.46 to 0.99) and median prediction error from leave-one-out cross-validation of 3.9%. Biomass per-unit-of-height was similar within but different among, plant functional types. We found that photogrammetric reconstructions of canopy height were sensitive to wind speed but not sun elevation during surveys. We demonstrated that our photogrammetric approach produced generalizable measurements across growth forms and environmental settings and yielded accuracies as good as those obtained from in situ approaches. We demonstrate that using a standardized approach for UAV photogrammetry can deliver accurate AGB estimates across a wide range of dynamic and heterogeneous ecosystems. Many academic and land management institutions have the technical capacity to deploy these approaches over extents of 1–10 ha−1. Photogrammetric approaches could provide much-needed information required to calibrate and validate the vegetation models and satellite-derived biomass products that are essential to understand vulnerable and understudied non-forested ecosystems around the globe.
Andrew M. Cunliffe; Karen Anderson; Fabio Boschetti; Richard E. Brazier; Hugh A. Graham; Isla H. Myers‐Smith; Thomas Astor; Matthias M. Boer; Leonor G. Calvo; Patrick E. Clark; Michael D. Cramer; Miguel S. Encinas‐Lara; Stephen M. Escarzaga; José M. Fernández‐Guisuraga; Adrian G. Fisher; Kateřina Gdulová; Breahna M. Gillespie; Anne Griebel; Niall P. Hanan; Muhammad S. Hanggito; Stefan Haselberger; Caroline A. Havrilla; Phil Heilman; Wenjie Ji; Jason W. Karl; Mario Kirchhoff; Sabine Kraushaar; Mitchell B. Lyons; Irene Marzolff; Marguerite E. Mauritz; Cameron D. McIntire; Daniel Metzen; Luis A. Méndez‐Barroso; Simon C. Power; Jiří Prošek; Enoc Sanz‐Ablanedo; Katherine J. Sauer; Damian Schulze‐Brüninghoff; Petra Šímová; Stephen Sitch; Julian L. Smit; Caiti M. Steele; Susana Suárez‐Seoane; Sergio A. Vargas; Miguel Villarreal; Fleur Visser; Michael Wachendorf; Hannes Wirnsberger; Robert Wojcikiewicz. Global application of an unoccupied aerial vehicle photogrammetry protocol for predicting aboveground biomass in non‐forest ecosystems. Remote Sensing in Ecology and Conservation 2021, 1 .
AMA StyleAndrew M. Cunliffe, Karen Anderson, Fabio Boschetti, Richard E. Brazier, Hugh A. Graham, Isla H. Myers‐Smith, Thomas Astor, Matthias M. Boer, Leonor G. Calvo, Patrick E. Clark, Michael D. Cramer, Miguel S. Encinas‐Lara, Stephen M. Escarzaga, José M. Fernández‐Guisuraga, Adrian G. Fisher, Kateřina Gdulová, Breahna M. Gillespie, Anne Griebel, Niall P. Hanan, Muhammad S. Hanggito, Stefan Haselberger, Caroline A. Havrilla, Phil Heilman, Wenjie Ji, Jason W. Karl, Mario Kirchhoff, Sabine Kraushaar, Mitchell B. Lyons, Irene Marzolff, Marguerite E. Mauritz, Cameron D. McIntire, Daniel Metzen, Luis A. Méndez‐Barroso, Simon C. Power, Jiří Prošek, Enoc Sanz‐Ablanedo, Katherine J. Sauer, Damian Schulze‐Brüninghoff, Petra Šímová, Stephen Sitch, Julian L. Smit, Caiti M. Steele, Susana Suárez‐Seoane, Sergio A. Vargas, Miguel Villarreal, Fleur Visser, Michael Wachendorf, Hannes Wirnsberger, Robert Wojcikiewicz. Global application of an unoccupied aerial vehicle photogrammetry protocol for predicting aboveground biomass in non‐forest ecosystems. Remote Sensing in Ecology and Conservation. 2021; ():1.
Chicago/Turabian StyleAndrew M. Cunliffe; Karen Anderson; Fabio Boschetti; Richard E. Brazier; Hugh A. Graham; Isla H. Myers‐Smith; Thomas Astor; Matthias M. Boer; Leonor G. Calvo; Patrick E. Clark; Michael D. Cramer; Miguel S. Encinas‐Lara; Stephen M. Escarzaga; José M. Fernández‐Guisuraga; Adrian G. Fisher; Kateřina Gdulová; Breahna M. Gillespie; Anne Griebel; Niall P. Hanan; Muhammad S. Hanggito; Stefan Haselberger; Caroline A. Havrilla; Phil Heilman; Wenjie Ji; Jason W. Karl; Mario Kirchhoff; Sabine Kraushaar; Mitchell B. Lyons; Irene Marzolff; Marguerite E. Mauritz; Cameron D. McIntire; Daniel Metzen; Luis A. Méndez‐Barroso; Simon C. Power; Jiří Prošek; Enoc Sanz‐Ablanedo; Katherine J. Sauer; Damian Schulze‐Brüninghoff; Petra Šímová; Stephen Sitch; Julian L. Smit; Caiti M. Steele; Susana Suárez‐Seoane; Sergio A. Vargas; Miguel Villarreal; Fleur Visser; Michael Wachendorf; Hannes Wirnsberger; Robert Wojcikiewicz. 2021. "Global application of an unoccupied aerial vehicle photogrammetry protocol for predicting aboveground biomass in non‐forest ecosystems." Remote Sensing in Ecology and Conservation , no. : 1.
The endemic argan tree (Argania spinosa) populations in South Morocco are highly degraded due to overbrowsing, illegal firewood extraction and the expansion of intensive agriculture. Bare areas between the isolated trees increase due to limited regrowth, but show lower soil quality than their neighbouring tree areas. Hypothetically, spatial differences of soil quality of the intertree area should result from translocation of litter or soil particles (by runoff and erosion or wind drift) from canopy-covered areas to the intertree areas. 385 soil samples were taken around the tree from the trunk along the tree drip line (within and outside the tree area) as well as the intertree area between two trees in four directions (upslope, downslope and in both directions parallel to the slope) and analysed for soil moisture, pH, electrical conductivity, percolation stability, total nitrogen content, content of soil organic carbon and C / N ratio. 74 tension-disc infiltrometer experiments were performed near the tree drip line, within and outside the tree area, to measure the unsaturated hydraulic conductivity. We found that the tree influence on its surrounding intertree area is limited, with e.g., Corg- & N-content decreasing significantly from tree trunk to tree drip line. However, intertree areas near the tree drip line differed significantly from intertree areas between two trees, yet only with a small effect. Trends for spatial patterns could be found in eastern and downslope directions due to wind drift and slope wash. Soil moisture was highest in the north due to shade from the midday sun, the influence extended to the intertree areas. The unsaturated hydraulic conductivity also showed significant differences between areas within and outside the tree area near the tree drip line. Although only limited influence of the tree on its intertree area was found, the spatial pattern around the tree suggests that reforestation measures should be aimed around tree shelters in northern or eastern directions with higher soil moistures, N- or Corg-content to ensure seedling survival.
Mario Kirchhoff; Tobias Romes; Irene Marzolff; Manuel Seeger; Ali Aït Hssaine; Johannes B. Ries. Spatial patterns of argan-tree influence on soil quality of intertree areas in open woodlands of South Morocco. 2021, 2021, 1 -26.
AMA StyleMario Kirchhoff, Tobias Romes, Irene Marzolff, Manuel Seeger, Ali Aït Hssaine, Johannes B. Ries. Spatial patterns of argan-tree influence on soil quality of intertree areas in open woodlands of South Morocco. . 2021; 2021 ():1-26.
Chicago/Turabian StyleMario Kirchhoff; Tobias Romes; Irene Marzolff; Manuel Seeger; Ali Aït Hssaine; Johannes B. Ries. 2021. "Spatial patterns of argan-tree influence on soil quality of intertree areas in open woodlands of South Morocco." 2021, no. : 1-26.
The endemic argan tree (Argania spinosa) in Morocco, which is the source of the valuable argan oil, forms open-canopy forests that are highly degraded due to overgrazing, illegal cutting of firewood and the expanding intensive agriculture. Because of the high grazing pressure young sprouts cannot establish themselves, reforestation measures are often unsuccessful and the bare areas between the isolated trees are expanding. In a previous study, we could already show that these intertree areas are more degraded than the areas under the trees, regarding various soil parameters as well as their erodibility and infiltration capacity.
The spatial extent of argan trees on soil quality from the trunk to the intertree area is so far unknown. Hypothetically, the tree influences the soil of the intertree area by wind drift of tree litter and soil material towards the East, i.e. main wind direction, and downhill by runoff and erosion processes of soil material downslope. Tree shadow in the hot midday and afternoon sun should have positive influences on soil moisture in northern or northeastern directions. To test this hypothesis, we took 424 soil samples around 31 argan trees in four directions, uphill, downhill and in both directions parallel to the slope towards the nearest neighbouring tree in that direction. Samples along these transects were taken near the trunk, just inside and just outside the area covered by the tree crown and in the intertree area in the middle between two trees. The soil samples were analysed for various soil parameters (C/N, percolation stability, electrical conductivity, pH, soil moisture).
The first results show that the influence of the trees is not limited to the crown-covered area but for some trees extends further into the intertree area in specific directions according to the hypothesis (East due to wind drift, North due to shade and downslope due to slope runoff). For other trees the influence of the trees does not even encompass the whole crown-covered area, where we found similarly lower soil quality as for the bare intertree areas. These differences may result from the degradation state of the tree as well as from the different characteristics of the study areas. Understanding the way argan trees influence their surrounding intertree areas would enable structured reforestation measures with a higher chance of successful rejuvenation of the argan forest.
Mario Kirchhoff; Tobias Romes; Irene Marzolff; Manuel Seeger; Ali Aït Hssaine; Johannes B. Ries. Spatial patterns of argan-tree influence on soil quality of intertree areas in open woodlands in South Morocco. 2021, 1 .
AMA StyleMario Kirchhoff, Tobias Romes, Irene Marzolff, Manuel Seeger, Ali Aït Hssaine, Johannes B. Ries. Spatial patterns of argan-tree influence on soil quality of intertree areas in open woodlands in South Morocco. . 2021; ():1.
Chicago/Turabian StyleMario Kirchhoff; Tobias Romes; Irene Marzolff; Manuel Seeger; Ali Aït Hssaine; Johannes B. Ries. 2021. "Spatial patterns of argan-tree influence on soil quality of intertree areas in open woodlands in South Morocco." , no. : 1.
In semi-arid to arid South-west Morocco, the once ubiquitous endemic argan tree (Argania spinosa) forms the basis of a traditional silvo-pastoral agroforestry system with complex usage rights involving pasturing and tree-browsing by goats, sheep and camels, smallholder agriculture and oil production. Widespread clearing of the open-canopy argan forests has been undertaken in the 12th–17th century for sugarcane production, and again in the 20th century for fuelwood extraction and conversion to commercial agriculture. The remaining argan woodlands have continued to decline due to firewood extraction, charcoal-making, overgrazing and overbrowsing. Soil and vegetation are increasingly being degraded; natural rejuvenation is hindered, and soil-erosion rates rise due to reduced infiltration and increased runoff. Numerous studies indicate that tree density and canopy cover have been generally decreasing for the last 200 years. However, there is little quantitative and spatially explicit information about these forest-cover dynamics.
In our study, the tree-cover change between 1967 and 2019 was analysed for 30 test sites of 1 ha each in argan woodlands of different degradation stages in the provinces of Taroudant, Agadir Ida-Outanane and Chtouka-Aït Baha. We used historical black-and-white satellite photography from the American reconnaissance programme CORONA, recent high-resolution multispectral imagery from the commercial WorldView satellites and ultrahigh resolution small-format aerial photography taken with an unmanned aerial system (UAS) to map the presence, absence and comparative crown-size class of 2610 trees in 1967 and 2019. We supplemented the remotely-sensed data with field observations on tree structure and architecture.
Results show that plant densities reach up to 300 argan trees and shrubs per hectare, and the mean tree density has increased from 58 trees/ha in 1967 to 86 trees/ha in 2019. While 7% of the 1967 trees have vanished today, more than one third of today’s trees could not be observed in 1967. This positive change has a high uncertainty, however, as most of the increase concerns small trees (< 3 m diameter) which might have been missed on the lower-resolution CORONA images.
When combined with our field data on tree architecture, tree count – albeit a parameter easily attained by remote sensing – is revealed as too simple an indicator for argan-forest dynamics, and the first impression of a positive development needs to be revised: The new small trees as well as trees with decreased crown sizes clearly show much stronger degradation characteristics than others, indicating increased pressures on the argan ecosystem during recent decades. Structural traits of the smaller trees also suggest that the apparent increase of tree count is not a result of natural rejuvenation, but mostly of stump re-sprouting, often into multi-stemmed trees, after felling of a tree. The density of the argan forest in the 1960s, prior to the general availability of cooking gas in the region and before the stronger enforcement of the argan logging ban following the declaration of the UNESCO biosphere reserve, may have marked a historic low in our study area, making the baseline of our change analysis far removed from the potential natural state of the argan ecosystem.
Irene Marzolff; Mario Kirchhoff; Robin Stephan; Manuel Seeger; Ali Aït Hssaïne; Johannes B. Ries. Degradation or recovery of argan woodlands in South Morocco? Tree count from satellite imagery between 1967–2019 may underestimate pressures on dryland forests status. 2021, 1 .
AMA StyleIrene Marzolff, Mario Kirchhoff, Robin Stephan, Manuel Seeger, Ali Aït Hssaïne, Johannes B. Ries. Degradation or recovery of argan woodlands in South Morocco? Tree count from satellite imagery between 1967–2019 may underestimate pressures on dryland forests status. . 2021; ():1.
Chicago/Turabian StyleIrene Marzolff; Mario Kirchhoff; Robin Stephan; Manuel Seeger; Ali Aït Hssaïne; Johannes B. Ries. 2021. "Degradation or recovery of argan woodlands in South Morocco? Tree count from satellite imagery between 1967–2019 may underestimate pressures on dryland forests status." , no. : 1.
The endemic argan woodlands cover large parts of South Morocco and create a characteristic landscape with areas of sparsely vegetated and bare soil surfaces between the single trees. This unique ecosystem has been under extensive agrosilvopastoral management for centuries and is now at risk of degradation caused by overgrazing and increasing scarcity and variability of rainfall. To investigate susceptibility to wind erosion, we conducted an experimental‐empirical study including wind tunnel tests and a drone generated digital elevation model and quantified wind erodible material on five different associated surface types by means of sediment catchers. The highest emission flux was measured on freshly ploughed surfaces (1875 g m‐2 h‐1), while older ploughed areas with a re‐established crust produced a much lower emission flux (795 g m‐2 h‐1). Extensive tillage may have been a sustainable practice for generations, but increasing drought and uncertainty of rainfall now leads to an acute risk of severe soil erosion and dust production. The typical crusted surfaces characterised by residual rock fragment accumulation and wash processes produced the second highest emission flux (1354 g m‐2 h‐1). Collected material from tree‐shaded areas (933 g m‐2 h‐1) was revealed as a considerable source of organic material possibly affecting substrate conditions positively on a larger regional scale. Lowest flux was measured on rock fragment covered surfaces (301 g m‐2 h‐1). The data show that open argan woodland may be a considerable source for wind erosion and dust production, depending on surface characteristics strongly related to management. An adapted management must include the conservation of the argan trees to offer a promising approach to prevent severe wind erosion and dust production and mitigate possible impacts of land‐use change and climate‐change related shifts in wind and rainfall patterns.
Miriam Marzen; Mario Kirchhoff; Irene Marzolff; Ali Aït Hssaine; Johannes B. Ries. Relative quantification of wind erosion in argan woodlands in the Souss Basin, Morocco. Earth Surface Processes and Landforms 2020, 45, 3808 -3823.
AMA StyleMiriam Marzen, Mario Kirchhoff, Irene Marzolff, Ali Aït Hssaine, Johannes B. Ries. Relative quantification of wind erosion in argan woodlands in the Souss Basin, Morocco. Earth Surface Processes and Landforms. 2020; 45 (15):3808-3823.
Chicago/Turabian StyleMiriam Marzen; Mario Kirchhoff; Irene Marzolff; Ali Aït Hssaine; Johannes B. Ries. 2020. "Relative quantification of wind erosion in argan woodlands in the Souss Basin, Morocco." Earth Surface Processes and Landforms 45, no. 15: 3808-3823.
Non-forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, yet are highly sensitive to climatic changes. Yet these ecosystems are poorly represented in remotely-sensed biomass products and are undersampled by in-situ monitoring. Current global change threats emphasise the need for new tools to capture biomass change in non-forest ecosystems at appropriate scales. Here we assess whether canopy height inferred from drone photogrammetry allows the estimation of aboveground biomass (AGB) across low-stature plant species sampled through a global site network. We found mean canopy height is strongly predictive of AGB across species, demonstrating standardised photogrammetric approaches are generalisable across growth forms and environmental settings. Biomass per-unit-of-height was similar within, but different among, plant functional types. We find drone-based photogrammetry allows for monitoring of AGB across large spatial extents and can advance understanding of understudied and vulnerable non-forested ecosystems across the globe.
Andrew M Cunliffe; Karen Anderson; Fabio Boschetti; Richard E Brazier; Hugh A Graham; Isla H Myers-Smith; Thomas Astor; Matthias M Boer; Leonor Calvo; Patrick E Clark; Michael D Cramer; Miguel S. Encinas-Lara; Stephen M Escarzaga; Jose M Fernandez-Guisuraga; Adrian G Fisher; Katerina Gdulov; Breahna M Gillespie; Anne Griebel; Niall P Hanan; Muhammad S Hanggito; Stefan Haselberger; Caroline A Havrilla; Philip Heilman; Wenjie Ji; Jason W Karl; Mario Kirchhoff; Sabine Kraushaar; Mitchell B Lyons; Irene Marzolff; Marguerite E Mauritz; Cameron D McIntire; Daniel Metzen; Luis A Mendez-Barroso; Simon C Power; Jiri Prosek; Enoc Sanz-Ablanedo; Katherine J Sauer; Damian Schulze-Bruninghoff; Petra Simov; Stephen Sitch; Julian L Smit; Caiti M Steele; Susana Suarez-Seoane; Sergio A Vargas; Miguel L Villarreal; Fleur Visser; Michael Wachendorf; Hannes Wirnsberger; Robert Wojcikiewicz. Drone-derived canopy height predicts biomass across non-forest ecosystems globally. 2020, 1 .
AMA StyleAndrew M Cunliffe, Karen Anderson, Fabio Boschetti, Richard E Brazier, Hugh A Graham, Isla H Myers-Smith, Thomas Astor, Matthias M Boer, Leonor Calvo, Patrick E Clark, Michael D Cramer, Miguel S. Encinas-Lara, Stephen M Escarzaga, Jose M Fernandez-Guisuraga, Adrian G Fisher, Katerina Gdulov, Breahna M Gillespie, Anne Griebel, Niall P Hanan, Muhammad S Hanggito, Stefan Haselberger, Caroline A Havrilla, Philip Heilman, Wenjie Ji, Jason W Karl, Mario Kirchhoff, Sabine Kraushaar, Mitchell B Lyons, Irene Marzolff, Marguerite E Mauritz, Cameron D McIntire, Daniel Metzen, Luis A Mendez-Barroso, Simon C Power, Jiri Prosek, Enoc Sanz-Ablanedo, Katherine J Sauer, Damian Schulze-Bruninghoff, Petra Simov, Stephen Sitch, Julian L Smit, Caiti M Steele, Susana Suarez-Seoane, Sergio A Vargas, Miguel L Villarreal, Fleur Visser, Michael Wachendorf, Hannes Wirnsberger, Robert Wojcikiewicz. Drone-derived canopy height predicts biomass across non-forest ecosystems globally. . 2020; ():1.
Chicago/Turabian StyleAndrew M Cunliffe; Karen Anderson; Fabio Boschetti; Richard E Brazier; Hugh A Graham; Isla H Myers-Smith; Thomas Astor; Matthias M Boer; Leonor Calvo; Patrick E Clark; Michael D Cramer; Miguel S. Encinas-Lara; Stephen M Escarzaga; Jose M Fernandez-Guisuraga; Adrian G Fisher; Katerina Gdulov; Breahna M Gillespie; Anne Griebel; Niall P Hanan; Muhammad S Hanggito; Stefan Haselberger; Caroline A Havrilla; Philip Heilman; Wenjie Ji; Jason W Karl; Mario Kirchhoff; Sabine Kraushaar; Mitchell B Lyons; Irene Marzolff; Marguerite E Mauritz; Cameron D McIntire; Daniel Metzen; Luis A Mendez-Barroso; Simon C Power; Jiri Prosek; Enoc Sanz-Ablanedo; Katherine J Sauer; Damian Schulze-Bruninghoff; Petra Simov; Stephen Sitch; Julian L Smit; Caiti M Steele; Susana Suarez-Seoane; Sergio A Vargas; Miguel L Villarreal; Fleur Visser; Michael Wachendorf; Hannes Wirnsberger; Robert Wojcikiewicz. 2020. "Drone-derived canopy height predicts biomass across non-forest ecosystems globally." , no. : 1.
The argan tree (Argania spinosa) populations, endemic to South Morocco, have been highly degraded. Although the argan tree is the source of the valuable argan oil and is protected by law, overbrowsing and -grazing as well as the intensification and expansion of agricultural land lead to tree and soil degradation. Young stands cannot establish themselves; undergrowth is scarce due to the semiarid/arid climate and thus, goats, sheep and dromedaries continually browse the trees. Canopy-covered areas decrease and are degraded while areas without vegetation cover between the argan trees increase.
On 30 test sites, 60 soil samples of tree and intertree areas were studied on their soil physical and chemical properties. 36 rainfall simulations and 60 single-ring infiltration measurements were conducted to measure potential differences between tree/intertree areas in their runoff/erosion and infiltration properties. Significant differences using a t-test were found for the studied parameters saturated hydraulic conductivity, pH, electric conductivity, percolation stability, total C-content, total N-content, K-content, Na-content and Mg-content. Surface runoff and soil erosion were not statistically significant, but showed similar trends due to the higher complexity of runoff formation. The soil covered by argan trees generally showed less signs of degradation than intertree areas. With ever-expanding intertree areas due to the lack of rejuvenation of argan trees a further degradation of the soil can be assumed.
Mario Kirchhoff; Lars Engelmann; Lutz Leroy Zimmermann; Irene Marzolff; Manuel Seeger; Ali Aït Hssaine; Johannes B. Ries. Soil Degradation in Argan Woodlands, South Morocco. 2020, 1 .
AMA StyleMario Kirchhoff, Lars Engelmann, Lutz Leroy Zimmermann, Irene Marzolff, Manuel Seeger, Ali Aït Hssaine, Johannes B. Ries. Soil Degradation in Argan Woodlands, South Morocco. . 2020; ():1.
Chicago/Turabian StyleMario Kirchhoff; Lars Engelmann; Lutz Leroy Zimmermann; Irene Marzolff; Manuel Seeger; Ali Aït Hssaine; Johannes B. Ries. 2020. "Soil Degradation in Argan Woodlands, South Morocco." , no. : 1.
The endemic argan tree (Argania spinosa) populations in South Morocco are highly degraded due to their use as a biomass resource in dry years and illegal firewood extraction. The intensification and expansion of agricultural land lead to a retreat of the wooded area, while the remaining argan open woodlands are often overgrazed. Thus, canopy-covered areas decrease while areas without vegetation cover between the argan trees increase. In total, 36 rainfall simulation experiments as well as 60 infiltration measurements were conducted to investigate the potential difference between tree-covered areas and bare intertree areas. In addition, 60 soil samples were taken under the trees and in the intertree areas parallel to the contour lines. Significant differences using a t-test were found between tree and intertree areas for the studied parameters Ksat, Kh, pH, electric conductivity, percolation stability, total C-content, total N-content, K-content, Na-content, and Mg-content. Surface runoff and soil losses were not as conclusive but showed similar trends. The results showed that argan trees influence the soil underneath significantly, while the soil in intertree areas is less protected and more degraded. It is therefore reasonable to assume further degradation of the soil when intertree areas extend further due to lack of rejuvenation of argan trees.
Mario Kirchhoff; Lars Engelmann; Lutz Leroy Zimmermann; Manuel Seeger; Irene Marzolff; Ali Aït Hssaine; Johannes B. Ries. Geomorphodynamics in Argan Woodlands, South Morocco. Water 2019, 11, 2193 .
AMA StyleMario Kirchhoff, Lars Engelmann, Lutz Leroy Zimmermann, Manuel Seeger, Irene Marzolff, Ali Aït Hssaine, Johannes B. Ries. Geomorphodynamics in Argan Woodlands, South Morocco. Water. 2019; 11 (10):2193.
Chicago/Turabian StyleMario Kirchhoff; Lars Engelmann; Lutz Leroy Zimmermann; Manuel Seeger; Irene Marzolff; Ali Aït Hssaine; Johannes B. Ries. 2019. "Geomorphodynamics in Argan Woodlands, South Morocco." Water 11, no. 10: 2193.