Landslides and Erosion

   

Our heartfelt condolences to everyone affected by the sudden landslide in Gofa, Southern Ethiopia, and our thoughts are with those who have lost their lives and their loved ones. We commend the ongoing rescue efforts to support families in grief and to re-establish society on a familiar and emotionally stable foundation.

CAUTION: The Slopes' Dangerous Restoration

Highly Contradictory Effects from Water

Sudden influxes of water, most often caused by human interference, can destabilize and damage the vacuum-anchoring suction effect in mountainous landscapes. This phenomenon, driven by human mismanagement, results in the accumulation of gravitational water pressure within the soil layers of hillsides over time, creating a dangerous, floating, and lubricating mass that exerts a driving force toward the settlements, a devastating threat of landslides and lahars. Furthermore, a previous reduction in trees removes root reinforcement, making the slopes more fragile due to the loss of root strength, and creates an additional hazard from water lubrication that ultimately saturates the ground. Furthermore, the root systems of indigenous vegetation help mitigate the potentially harmful effects of waterlogging on degraded land. Hence, the roots of indigenous trees' soil suction reduces the lubrication of the clay layers in the slopes, thereby reducing the risk of landslides. Furthermore, native vegetation and tree roots also block water from building up strong erosive forces, which otherwise accelerate and generate devastating torrential flows that tear up the ground beneath buildings and penetrate deeply into the riverbanks of settlements.

 

A complex and challenging problem can often require simple examples that appear adequately illustrated. To claim, for instance, that a soil mass on the mountainside weighing down with water can both be stabilising on a steep slope and, at the same time, fatally dangerous under other circumstances seems to invite misunderstandings that can be extremely serious.  

 Therefore, if a smaller shipping container: 

• 1. is placed on a steep mountain slope and weighed down by a certain mass of soil; while attempts to push it further down the hill, its downward motion is limited and most often to only a few centimetres with great effort. 

• 2. Conversely, if the container is emptied of all its soil, the situation changes dramatically, indicating that the container can now slide down the mountain slope more easily. 

• 3. It is now relatively easy to imagine that a container with soil will be even more difficult to push when weighed down by water on the top of its already heavy soil load.

• 4. Then, both soil and saturated with top water pressure, this container is given a drastic treatment: its bottom section becomes pierced with continuous perforating holes, and it is then again placed on the steep rock slope. 

• 5. When this perforated container, with its soil and top water pressure, is placed on the same mountain slope as the previous containers, it becomes evident that a highly slippery, muddy slurry (Soil liquefaction) immediately exudes with a positive overpressure, thus the opposite of vacuum suction. This lubrication of mud and soil liquefaction under positive overpressure between the container and the mountain slope constitutes, then, a slightly advancing experiment on the classic sliding grease bed, historically used to launch larger ships.

• 6. To visualize a vacuum suction between the bedrock and the small shipping container, imagine a machine-driven vacuum suction heavy-duty rubber bell being air-tightly closed over the upper section of the shipping container. The powerful, machine-driven vacuum-suction rubber bell is firmly attached, and the suction pressure then increases in the upper section of the small shipping container. This overlying vacuum pressure then propagates downward through the container, finally reaching the bedrock below. Depending on the strength and air-tightness of the vacuum suction technology and the toughness of the clay mass surrounding the shipping container on the bedrock, an adhesive vacuum suction may appear unavoidable. In many ways, the image described here provides insight into the deep, extensive roots of the endemic trees' ability to draw water and create a local vacuum suction at their contact with the bedrock.

The vacuum-anchoring suction effect results from the gravity pressure
built up over time in the layers of the hillside, where the evolution 
is a candidate for suspecting large trees as essential for gravity
 anchoring suction on the mountainside. 
Water and Land Restoration

Landscape Restoration

Thus, from Nature's ancient past, the mechanical compression of moraine and clay towards the mountainside provided Nature with the required strength for an evolutionary and mechanical suction base, facilitating the continued prehistoric build-up of the ancient soil layer. Reproducing Nature's prehistoric and evolutionary reinforcement of a barren, eroded slope by using shallowly planted, fragile indigenous saplings certainly poses a hazard to settlements beneath them. Usually, decades before any reinforcements from the root reinforcement of planned saplings arrive. In contrast, the use of technology, such as gabions with cliff anchors, offers a safer means of preventing dangerous landslides while also providing an essential base for the growth of endemic saplings. As an intervention that artificially rebuilds millions of years of accumulated ground stability in concert with soil layers and the evolution of organisms, it often seems impossible to recreate a lost ancient ground within a single generation.  

Nature Restoration with Modern Technology

However, some modern technologies, such as gabion baskets and mountain anchors, can frequently replace lost ancient stabilizing sediments and the crucial reinforcing strength of lost ancient tree roots. Gabion technology and rock anchors are current techniques that can enhance safety for settlements by providing new stable ground for plant growth on slopes. By backfilling and imitating ancient sediments, supported by gabions and rock anchors, the growth of Nature's basics may provide sufficient time for a landscape damaged by human hazards such as landslides and prehistoric erosion to heal.

The Importance of Domestic Trees

Reinforcement of Native Roots Against Erosion

The composite image series above invites a more
comprehensive study with explanatory images
of the water's flow and ground infiltration.
The Torrential Rains and Erosion

Erosion: The soil-holding capacity of Eucalyptus is relatively low compared to the original Ethiopian ground cover and trees that initially covered the slopes of Entoto. Because there is no ground cover in the foreign-implanted Eucalyptus forest, the only thing to hold the soil is the sporadic web of roots of the trees. This lack of soil-stabilizing undergrowth causes severe erosion, as evidenced by the water that runs through Addis during the rainy seasons. During each rainfall event, torrential runoff erodes valuable nutrients, and the fertile soil layer becomes thinner. Without proper care and preservation, within a few years, there will be no fertile ground for new vegetation, and the erosion will be irreversible.

Flooding: On Entoto, people collect every fallen leaf and branch, whereas in a natural forest with endemic vegetation, organic material from leaves, wood, roots, etc., is left to decompose in the soil. The organic compost from endemic vegetation improves soil structure, leading to higher infiltration rates and greater water storage capacity, and, of course, provides the fragile saplings with a primary foundation for growth. The picture series (4) - (7) to the left simplifies the connection between land and water, which can be seen by the vertical connection in the study of the infiltrating movements of the water in pictures (5 ) and (7).   Technology for Building Strength on Slopes

Civilisation's Hazardous Repair of the Mountains' Slopes

Restoring Nature with Concealed Technology

It is quite strange that a natural restoration approach appears directly inappropriate for addressing erosion damage that has ravaged deep into the mountain's soil layers and moraine. Therefore, attempting to restore the mountain to its original natural habitat on a steep slope through highly hazardous methods may, unfortunately, reflect humanity's superficial shortcomings, often sustained by corrupt undercurrents. Hence, such well-known shortcomings in the last century's legacy of dam disasters provide a stark backdrop to a behaviour that poses an imminent danger to downstream villages from landslides and lahars, especially when located beneath steep mountain massifs. Therefore, during steep slope restoration, recreating and replicating Nature's unique habitat, which Nature has formed over millions of years, may require additional stabilizing methods derived from ground technology. Such heavy-duty ground technical management appears appropriate here, where methods are often supported by civil engineering measures, including gabions anchored in the underlying rock, retaining walls, terracing and other stabilizing measures. The anchored gabions can provide an underground stabilizing foundation against landslides and further erosion, while simultaneously providing a base for reconstructing soil layers required for native vegetation. Thus, these underground anchored gabions in the landscape represent a possible replacement in terms of reliability and strength, aiming to recreate the original landscape and Nature.

The Environment,
Culture and Prosperity

The Importance of Indigenous Trees

Ethiopia's Prehistory of Natural Wealth

The native Ethiopian vegetation served as a highly effective physical barrier, blocking the country's water masses from rushing down its slopes toward Egypt. From Nature's ground, a picture of the soil's water-absorbing structure and root configurations emerges. Thus, along with the strength of the intricate network of endemic vegetation and the native undergrowth, the seasonal deluges had sophisticated water-holding capacity in Ethiopia's thick soil layers.

Natural Reservoirs (Aquifers) within the Landscape

Therefore, after the downpours, with their root reinforcement, the deep soil layers and ground moraine delivered purified water into the terrain's deep aquifers as groundwater. Hence, this original vegetation functioned as numerous efficient water collectors, with an intricate network of stems and deeply anchored roots, thereby stabilizing the soil and providing substantial resistance to erosion. 

 

Nature's Precious Cradle of Noble Life

Within this hidden enigma at the beginning of life lies the precious synergy between the ground and plants, enabling them to build tremendous strength within the ground's structure. This ground, formed by Nature in the remote past, served as the evolutionary cradle for the origin of more complex organisms. Therefore, all high-level living organisms today exist because of the preceding development of plants with their roots and the surrounding earth. Hence, the organism became intricately interdependent, with plants and their roots serving as the primary soil stabilizers and purifiers of the soil and aquifers. Therefore, historically, Ethiopia's considerable rainfall resources were less contentious, mainly because the abundant natural vegetation in its highlands still enabled the deluges to remain stable within the depths of this mountainous landscape.

The History of the Environment

The History of the Environment

The Prehistoric Legacy of Water and Plants 

The prosperity of civilizations across cultures and regions of the World indicates a clear connection between in-depth knowledge of biology and a culture's potential for development. Undoubtedly, this role is considered healthy in this context and in other sciences as well. Still, it is particularly evident in biology, as it is so closely related to human health and well-being. However, the insidious hierarchical governing terror of the past caused severe scares among many nations, inflicting humiliation in severe starvation and fearful aversions, thus damaging the population's most critical needs for safety. 

Ethiopia's Indigenous Vegetation 

A Heritage with Tremendous Potential

In the past, endemic vegetation served as a natural barrier, preventing precious water from being wasted by violent torrents. This seasonal water flow over the Ethiopian Highlands then historically, and even more prehistorically, infiltrated the deluges into soil permeability and vertically delivered this mass of purified water to be stored as natural groundwater within ancient aquifers. Hence, the fabric of these original vegetation's roots and soil functioned as numerous efficient conduits for deluges, directing them into Ethiopia's deep soil layers and the country's mountain massifs' aquifers, thereby preventing groundwater shortages during prolonged droughts.

 

The Healing Nature of the Native Forest

 Restoration With Original Trees and Plants

Benefits from the Establishment of the Park

Indigenous Trees: A Legacy Of National Importance

The natural health and fertile beauty of this indigenous Juniper forest illuminate, with precision, the healing capacity of a native forest and the severe destruction of nature and habitats that occurred with the introduction of the Eucalyptus tree. Due to these shortcomings in the Eucalyptus plantation's water-retention capacity, it cannot counterbalance the uneven distribution of rainfall. Therefore, this eucalyptus poisoning of the ground creates a highly water-repellent fabric in the upper soil layer, all too often followed by torrential flash floods and flooding in downslope areas. 

A Historical Nature Of  Environmental Importance

The Indigenous Vegetation To Groundwater

The native forest and scrub are essential for creating groundwater in the natural mountain reservoirs of underground aquifers. This original ground occurs in natural areas with dense undergrowth and indigenous biological structures, unique to places such as established national parks, which are well adapted to withstand erosion. This phenomenon of tree-ground interaction appears best described as a synergy in which indigenous vegetation is crucial for distributing rainfall and preventing environmental degradation. These careful considerations of the native Nature appear in a complex and beautiful picture of lifeforms, where they have optimized their genetic code over aeons of evolutionary symbiotic networks. Thus, through this evolution in antiquity, the natural forest developed immense strength in generating groundwater and in its exceptional capacity to withstand erosion. Furthermore, it's essential to understand the precarious synergy between the native plants' highly advanced biology and the ground they have shaped over aeons.

The Indigenous Podocarpus falcatus

The Highland's Clean Air & Clean Water

Sanctuaries and Museums, and Studies

The experience of Ethiopia's original, naturally fertile beauty near Addis Ababa, with fashionable facilities and historically significant Sanctuaries and museums, will attract many people every season. Schoolchildren will be actively using the Park for environmental education purposes (or to find a peaceful spot to do homework. Restaurants and amenities at Entoto Kidane Mehret (1), Entoto Maryam (43), Entoto Park (Z) 

A Source of Health for the Capital
A Natural Park for Weekends and Tourism
Tourists (mainly international) will enjoy views of Addis, a visit to a restaurant on a hot afternoon, and the calm of the juniper forest. Regular citizens of the Capital will mainly come on weekends. Still, visiting parks in Addis Ababa is a cultural habit, so visitors are expected to be high on Saturdays and Sundays.  (Håkan Blanck and a Englund, Entoto Natural Park 1995).  Accommodation and Other Services

The Torrential Rains & Erosion

Historical Background: [Foreign Chemical]

This chemical component in the foreign Australian Eucalyptus tree causes severe erosion, as evidenced by the water running through Addis during the rainy seasons. Regretably, for every rain period, the layer of fertile soil gets thinner. However, with the introduction of the Park in 1995, Ethiopia's obvious duty led to a genuine commitment, as the revival of a historical Nature found the country's true cradle by restoring a landscape capable of creating healthy freshwater, reflecting a nation's natural character. 

Erosion: Caused by this Eucalyptus tree's chemical, the only thing to hold the soil was the sporadic roots of the trees. Due to erosion caused by Eucalyptus trees, the reintroduction of indigenous trees reached a critical point. Videos: Soil Erosion Demo

Pinterest: Ethiopia's Work and Obligations

 

Grandiose Waterways in the Landscape

𝑊𝑎𝑡𝑒𝑟 𝐶𝑟𝑒𝑎𝑡𝑖𝑜𝑛 𝑤𝑖𝑡ℎ 𝐺𝑟𝑎𝑛𝑑 𝐵𝑒𝑎𝑢𝑡𝑦

The historical records reveal several practical and aesthetic possibilities for restoration. These options for an aesthetic restoration include water management, ground stability, and the most attractive recreation paths. Another way to describe these methods for natural conservation is the effectiveness of the irrigation method when combined with gentle, scenic hiking trails above precipices. Through these micro canals' associated need for strength and reliability, this need for reinforced waterways coincides with the suitability of dramatically beautiful and safe hiking trails where the steep slopes above or beneath these paths deliver an extraordinary beauty over grand views of often impossible precipices. 📸: From Wikimedia Commons, Fasilides Bath, Gondar, Ethiopia.

CAUTION: The Slopes' Restoration

Sudden influxes of water in the mountains can cause instability and damage to the vacuum-anchoring suction effect, which results from the gravity pressure that accumulates over time in the hillside layers, further driven by the vacuum suction of large indigenous trees' roots into deep soil layers. Furthermore, historical mismanagement, including severe deforestation and reduced tree cover, removes root reinforcement, which over time increases the slope's hazard and makes it more susceptible to erosion and failure due to reduced root strength and increased water lubrication (soil liquefaction). Furthermore, the stability of native vegetation and tree roots also prevents water forces from accelerating and producing devastating torrential flows, in which water masses erode the ground beneath buildings and penetrate deeply into the riverbanks of settlements.

Restoring a severely eroded landscape through the reintroduction of native vegetation can be a complex process. Because soil layers formed over millions of years have lost their original strength, the tremendous stability provided by the tree roots and compact sediment has often disappeared. It is, therefore, a colossal project to remedy these prehistorically formed soil layers, which have been tested by aeons of Nature's hardship during ages of severe rainstorms, flash floods, or drought, and thus evolved to optimize their environment, along with the natural environment of the underlying mountain slope. Therefore, when considering a natural mountain slope in terms of health, the conclusion follows with a significant probability that the most resistant soil layers remain; however, the caveat is that they only exist due to the vegetation's roots, assisted by vacuum pressure and organisms that created their own rock gripping anchor points underneath their soil layers. Thus, since prehistoric times, trees' roots have provided mountain slopes with a robust, reinforcing biological structure whose strength and toughness can surpass that of much of everyday infrastructure.

Over millions of years, a mountainside subjected to severe environmental stresses yields a moraine with soil layers and vegetation that are highly resilient and often evolutionarily optimized to survive the specific environmental conditions of varying rainfall, drought, landslides, or lahars. After these lengthy trials over aeons of Nature's trial and error, what remains is a highly optimized habitat, and therefore very difficult to surpass. These are insurmountable circumstances, and attempting to replicate ancient ground and Nature's risks is an overwhelming safety concern and is likely to result in failure when restoring a steep hillside. If human civilizations are to overcome these difficulties, a great effort of human resources and technological stabilization measures is often required, such as 

Terracing | Gabion Baskets  |  Retaining Walls |  Mountain Anchors.

Pinterest: Planting Saplings

Keyline Design Permaculture

Terraced Micro-Basins

Planting Technology

Check Dam Swales

Soil Suction: https://www.sciencedirect.com/topics/engineering/soil-suction