Sepp holzers ponds.
ponds as water cisterns, fish farms, irrigation, drainage, to break the downward push of landslides the land above them is sepeartaed form the soil bleow them, the continuity of the top soil is. broken , as silt traps.
They also reflect the sunlight on to trees as the mirror surfaces in solar
cookingcreat more heat because they reflect the sun light so htat your pot not only heats form exposure to direct sunlight but also from the lsunlight reflected on to it from oother surfaces the mirrors you have set up. if however you put in you rond so it is shaded from the sun by trees it will cool rather htan heat your space.
The forth types of hollows made to better water permeation in land used to grow food are ponds.
There is the series of ponds on Sepp Holzer land that serve as cisterns but double up as fish ponds. In Germany they eat fresh water fish not habitually eaten in England. My parents were there once and got served pike, if I remember right.
Making sure water permeates your land well helps rivers, it drips out of the land slowly and so helps people lower down the stream receive an steady flow of water instead of being awash with water after a storm and later having none.
The ponds like swales help the water to really permeate the earth. Sepp Holzer has a number of ponds that constitute a irrigation system as the water from them seeps into the landscape slowly. This according to him creates damp soil without creating those excesses of water that move through the soil leaching nutrients out of the soil with the water that washes through the soil. Too much water that leaches goodness out of the soil can be one of the disadvantages of irrigation
The ponds also mean the trees have a supply of water whether or not Sepp is there to water them.
He also uses the water that flows out of them to turn a water wheel and provide his house with electricity.
The overflow from the Sepps ponds goes down pipes into the next pond down or to drive his water wheel. I don’t know exactly how he works it.
In a youtube video of Sepp Holzers, “ work in the Ecuador against natural disasters”, He says that ponds stop landslides. This is another aspect of ponds on hills.
If the wet mud starts to slide pushing the wet mud in front of it, then, if you have a eaten out a bite of the slope where you have built a pond, the mud can only slide till it falls into the pond the pond will break the chain reaction, the falling mud can’t push the mud downhill from the falling mud it will have fallen in to the pond. Instead of going on pushing the mud in front of it there wont be more mud in front of it until the otherside of the pond a place the falling mud will never get to. The ponds will shorten landslides. So ponds to break the flow of mud slides.
If mud falls into a pond most of the mud will sink into the pond so it will be water that overflows from the pond not mud, The mud will displace the water in the pond. If the overflow pipe is big enough a lot of the extra will go down the pipe and not wet the already soaked hill. This must also reduce the damage a landslide can do.
Sediment Ponds that reduce flooding down stream.
In engineering swales can be used to carry water into a sediment trap which is a pond where the sediment will fall to the bottom and the clean water will be on top. In a building site you would not want all the sand of the site to end up on other peoples land so you construct a a sediment trap and a swale to carry your sandy water to the trap. You can find a description of this if you tap into youtube the words “ dikes berms
and swales. Erosion and sediment control fact sheet”.
As one reason for flooded rivers can be that the mountain slopes near the rivers source have been bared of protective vegetation by over exploitation, overgrazing, and rainfall causes a lot of erosion carrying mud into streams that carry it into rivers. With the earth bared though there is not an actual mud slide the rain fall is going to carry a lot of mud downhill to the streams with it and so a lot of sediment into the rivers. If rivers get silted up there is much less room for water in them, so that if there is a big water event a lot of rainfall the rivers are more likely to overflow, their courses no longer big enough to carry the water from a heavy rainfall event . So stopping mud getting into rivers helps stop disasters.
Sediment ponds can stop the mud that has eroded off hills getting into rivers as the sediment sinks to the bottom of the ponds and does not get to the rivers only silts up the ponds.
This function of his ponds is given in Sepps video, on you tube “ work in Ecuador against natural disasters”
In Sepps ponds we know the water that drains off the pond is taken off from the surface water as it flows down an overflow pipe is taken from the surface. His overflow pipes head is near the surface of the pond so when the pond level rises, the water ¡rises above the top of the pipe and flows down it. A plug hole in the air. So in Sepps pond, the drainage, the water that flows down pipe comes from the clean, sediment free
, top part of the pond. This must mean that the pond slowly fills up with sediment and needs to be cleaned.
So sediment ponds such as Sepps as well irrigating the slopes of the hills they are embedded in in dry weather can catch sediment coming off the slope and stop flooding,down stream, be disaster saving ponds. The sediment falling off the hill ending up in the bottom of the ponds instead of in the rivers .
Also they are part of a drainage system, if you control the water flowing out of them providing channels for it to go down the slope in or water pipes, Sepp has big water pipes to carry of the overflow from his ponds, you reduce the water that wets the mud making it too heavy to stay put, by draining the water down hill away from the slopes.
A lot of rain will fall in the ponds instead of onto the banks and be siphoned of into channels or pipes. This is a third reason ponds can stop mudslides.
So. cisterns, irrigation, fish ponds, , electric power source, a break to mud slides, drainage and sediment trap.
The ponds are cut deep into the slope so they are far from the surface of the slope and from the part of the slope likely to be part of a mud slide. Though I suppose there must always be the really bad occasion when half the slope will fall down ponds and all.
If you look at the diagram of the ponds on a slope in Sepps video, work in Ecuador against natural disasters , you will see the ponds are set way into the slope, their weight and water content is not on top of that last two or three meters of land that wet through and precipitate down the slope in a land slide .
All these ponds change your landscape which might be a struggle if you have got fond of the land as it was. Agri rose macaskie.