Balanced Forest

How the forest is protecting the water you drink

Do you know where the water you drink is coming from? If your water is coming from an area covered by forests, you are a lucky one as chance are that you are enjoying a very high quality water. You don't know it, but the quality of the water you drink comes from the quality of the forest it went through. The forest and its soil have huge impact on the quality of the water.

First, what is good water? You basically have three points to check to verify the quality of your water:

• Does it contain the right oligo elements and minerals?
• Is it free from bad chemicals?
• Is it free from deposits?

So, clear water does not mean good water, because it can easily contain bad chemicals. The well known problematic ones are nitrates. The nitrates are used a lot in agriculture to carry Nitrogen to the plants which is a fertilizer. The main problem is that if you put an excess of nitrate based fertilizers on your field, the plants are not going to absorbe everything and it will go through the ground and then will end up in the water you drink. Or maybe the water you were used to drink because now it is polluted and you can't drink it anymore. Nitrates have different sources, it can be produced by chemical reactions or simply using animal dejections. For example, in Britany in France, you cannot drink anymore the local water because so much porc dejections were spread on the fields to evacute them that the water is completely saturated by nitrates. It will take years to be able to recover the quality of the water.

Then of course you want your water to be clear, that is, whitout deposits, to do that you need to mechanically filter it. And you want to have the right chemicals into it, like calcium.

How forests are helping to have this high quality water? The soil of the forest, when developed in a sustainable manner, is very rich in micro organisms. These micro organisms are decomposing the complex molecules as they are using them as a source of energy (it is food for them). As bad chemicals are complex molecules micro organisms are cleaning the water from chemicals. Of course, it is always a questions of balance, if you saturate the forest with polluted water, you cannot expect miracles, you can kill the bacteries and the forest all at the same time. So please do not dump the old chemicals you have at home in the forest, you have specialized places to deposit them.

The soil of the forest is also acting as a very big mechanical filter, all the little stuff are getting stuck into it, and then at the end you have clear water. In fact in water plant, they are using the same technics to clear the water by pushing it through sand to fix the deposits.

The presence or not of the nice elements is not really coming from the forest, as the quality of the minerals is coming from the deep under quality of the soil. That is why you have some mineral waters which are richer than others in given minerals. But the forest is helping the water to get absorbed in the ground at a low speed, without forest, the water is washing the ground and end up in rivers without going first through the soil to be loaded with the good minerals.

In fact forest is so good for the water, that in Switzerland, they are directly using the forest to clean the water. The page is not available in English, but basically, they are pumping the water out of the Rhin river to let it recover some special area of the forest and collect it under the ground downhill. They do not need any treatment of the water, the water is ready to be enjoyed.

# Published by Loïc, December 9, 2006 | 138 commentaires.

The satellite to observe the forest

Today, I will show you an area of the forest from above. The area I will talk about is basically on parcel 22 and a little on parcel 23. You can see an even better resolution when going directly on the Géoportail website. Saddly, first, the website is in French, and second, it is not possible to give a direct link to the map like with Google. So to simplify, here is a screen capture of the area:

This is an aerial photo taken in 2001 by the IGN, which is the French national institute for all the things related to geography. They are basically the ones making maps. I have labelled 3 zones from 1 to 3, with zone 3 being part of the zone 2.

The satellite to observe different technics

Zone 1 show a very rational management technic. The principle is to have a complete parcel being mature and ready to be cut at the same time. So you harvest everything and then you start again with new young trees. Rince and repeat every 40 to 70 years depending on the growth speed of the spieces. You can easily spot in this zone parcels with different level of maturity. This goes from very young trees (or maybe nothing because coming out of the harvest) to older ones, here on the North of the zone.

When they are cutting, they are doing a white cut, that is, they are cutting everything. This is very practical, because it is decreasing the cost of production because when you cut, you basically do not have to take care of the younger trees and you do not have to ensure that the trees are falling in the right direction to minimize the damages when they are taken out of the forest.

If you push this technic to its maximum, you can find the result here in Canada as shown on this Google map. Take a look at the scale, it is impressive, the white lots are not few hundreds square meters like on the shot I just described, but thousands. They are doing that directly on many hectares. This has been found by Dave Shea.

The ecological impact of a white cut is hard to assess, but it has been shown that during 10 to 12 years after the white cut, the Carbone balance of the lot is negative, that is the ground is releasing more CO2 in the atmosphere than what it is absorbing, even with young trees on it. It is also perturbing the animal life and can weaker the trees left as they are making tunnels for the wind which can damage the trees on the border. Oh, it is also very hugly a white cut.

On the other side, zone 2 is not that interesting from above, it looks nearly the same from everywhere. But please, come and take a look at the ground, the level of diversity under the roof is high as we are doing sustainable forestry management, that is, we harvest not everything at the same time and we ensure that when the old ones need to be cut, already some younger trees are there, big enough to stabilize the soil and ready to take over. The parcel will give not a lot, but every few years (not every 40 to 70 years).

But zone 3 shows that it is not always possible to do that, even if we take great care, diseases can spread, a storm can break a lot or simply the quality of the ground was such that it was not possible to foster younger trees under cover. It may also be the case that the manager decided to make a big change the species, so yes sometimes we do white cut, but they are the exceptions not the rule.

The satellite to track the others

Today you cannot hide. Even if the forest is closed because of private hunting lot, you can always use satellite imagery to see what is going on. The Géoportail website is really impressive, simple (ok, not as simple as Google Maps) and with really high resolution pictures.

# Published by Loïc, December 8, 2006 | 12 commentaires.

Welcome on Balanced Forest

Welcome on Balanced Forest! If you are interested in sustainable development and CO2 sequestration. Especially CO2 sequestration by the forest, you will find here quite some useful resources. Enjoy!

# Published by Loïc, November 30, 2006 | 10 commentaires.