The Conservation and Improvement of Sloping Lands

by Peter Storey

is the title of a set of books I have written. I will give some points from it.

1. Soil conservation.

Shortly after arriving in Taiwan in 1963 I observed horrific soil erosion in the mountains caused during Typhoon Gloria. My first experience of soil conservation was in 1965. At that time I was involved in agricultural extension work, and in teaching, at the Yu Shan Mountain Peoples Agricultural Training Centre.

    I set up a soil conservation trial with different conservation practices, with all details such as labour required and crop yield for each method recorded on sign boards. That and subsequent work came to be of interest not only to our own students but also to other mountain people who came to visit the farm, observe and ask questions. The trials showed clearly that the different contour strips and half terraces were losing fertility while the terraces were not.

    When I took on the job of farm manager in 1966 the farm was scarcely using its mountain side land, and what was used was an example of 'how not to farm it'. I set about reversing that situation. The razor grass (Imperata cylindrical) covering the land was cut and composted, appropriate terrace lines were marked out and the larger rocks moved onto them. Terraces were then built keeping most of the top soil on top. Where the land was too rocky the soil was scraped off and put into the spaces between the rocks and bananas and Green leaf Desmodium planted. We heard that Government experts were puzzled as to why mountain farmers were starting to make terraces, which they would not do when they had been directed by the 'experts'. Later a high level group including FAO representatives and the Government Minister of the Interior on a tour of agricultural establishments visited the farm and were very complementary.

After further study and working in another part of Taiwan I was sent to start a new project which grew to cover 45 villages and again developed a piece of hillside. By that time labour costs had risen, however most villages had at least one walking tractor. I designed a bulldozer conversion kit which could be fitted to any of the walking tractors in Taiwan. It proved very effective in making terraces and could also be used for making paddi fields. fish ponds farm tracks etc.

    We used the bulldozer to make terraces by the throwing down method, it was quick and relatively easy. The bulldozer was amazingly stable and in fact when starting each strip we could use it crabwise where a conventional bulldozer would be likely to turn over. Once in fact, the lower wheel did slip into a hole and the tractor turned over onto the terrace below, however we easily rolled it back over and continued. The result a terraced hillside with the terraces not a set of wedges resting on a slope, and so liable to slide as sadly occurs too often, but terraces keyed into the hillside, and the topsoil on top instead of all or most of it being buried, I have seen grandiose schemes in both Taiwan and Nepal where the latter has happened.

In 1979 I handed over the developed project to local people and took some further training .

    In 1980 when I went to Nepal I wanted to try various methods of soil and water conservation as steep erodible slopes were used to grow maize and wheat; with a high degree of rainy season soil loss, up to 2.5 inches (6.4cm) per year. Pictures of Nepal and so called studies of soil conservation there are only from certain untypical areas. In 1982 I was able to establish soil conservation trials on laterite soil, comparing the normal slope cultivation with the government promoted contour strips, half terraces and full terraces.

     The following year we developed another piece of land with very different soil conditions, it was very stony. We again included soil conservation trials, simultaneously I was observing what was happening to other land in the district. That experience confirmed that good terracing was the only sustainable way for crops to be grown on hillsides. Now we had to develop a method which was feasible for local farmers using manual labour. Terracing is often regarded as unsuitable or inpractical because of the way it is usually carried out. However I know from experience that terracing can and should be both suitable, practical and economical. Fair criticism of dry terrace construction is that:

. (A) they are most often made by simply dragging the soil down hill until there is a level wedge of loose soil. In the rainy season this loose soil may become waterlogged and heavy and start a landslide. The precious topsoil is lost and the land below is also spoilt.

(B) The first soil loosened and moved is the fertile topsoil which form the bottom of the wedge. Next is the poorer half fertile under soil; and lastly the infertile subsoil becomes the infertile surface of the terrace. Even with heavy manuring this soil gives poor crops, while the rich topsoil is wasted underneath.

(C,) Such terraces are usually created by outside projects rather than by the farmers themselves. So the work is done poorly, and there is often little interest in maintaining them.

(D) The terracing is often highly labour intensive, or uses expensive earth moving equipment, both methods being uneconomical.

There are several ways of constructing terraces, but few are created for dry conditions, most are used for the making of paddy fields.

The reasons are that : -

I. Paddy fields usually grow more valuable crops than dry land crops, so the labour of making them is considered to be more worthwhile.

2. When terraces have been made for paddy fields, water is run into the field and mixed with the soil to make mud. The mud is trodden by bullocks and or people to consolidate the terrace. The mud is further stirred and trodden down until the terrace is sealed and pond like to make it into a paddy field. Because of this water does not soak through into the soil underneath risking slippage, and so terraces made into paddy fields are usually successful.

The Good News Terrace System was developed in response to the need to develop credibility quickly, a method which is feasible for ordinary farmers to manage with the help of a neighbour.

    The concept behind it is to stop the loss of soil and plant nutrients as quickly, simply and effectively as possible. This is done by first making pilot terraces at what will eventually be one out of three or four terrace spacings. The pilot terraces are not made full width and so can progress quite quickly. The loss of water, soil and plant nutrients is stopped by the pilot terraces, so that as most farmers in countries like Nepal have less than 0.5 hectare the loss of soil and nutrients across the sloping fields is checked in one or two years. The crops on the terraces grow much better, giving the farmers the incentive to continue the terrace making. Later, as the farmers have time and resources, they convert all their remaining slope land by stages into sustainable fully terraced: fields. With oxen to plough to loosen the soil Good News Terracing can be done by only two people or even one person, it results in:

a) stable terraces, and

b) terraces where most of the topsoil will be on top,

c) better crops, the ability to improve the soil and hope for the future.

2  Bamboo for soil conservation.

On arriving in Nepal after 16 years in Taiwan I noticed the relative scarcity of bamboo. Degraded land and landslide areas which are covered in useful bamboo forest in Taiwan were bare and worsening. The results of careful research work in Taiwan in the early 1960s had shown that: On very steep hill sides, gullies, eroding and landslide areas, and on very poor land, it was best to grow bamboo. The government then designated such land as bamboo areas and nothing else could be grown there. The bamboo planting proved to be a very good policy, transforming areas which were, or were becoming, useless and dangerous, into valuable income generating land, so conserving water and soil and improving the soil.

Bamboo has many commercial uses, paper and card manufacture, bamboo plywood, laminated boards, and cheap building materials, it is used for scaffolding, furniture manufacture and the manufacture of baskets, matting and handicrafts. The leaves provide good quality fodder for animals. In addition there is great potential for its use in soil conservation and in rapid replacement of forests on land unfit for crops.

    Bamboo can be grown on landslides and check their development. It can be grown on denuded areas absorbing the run-off from them, which is a common cause of landslides, so preventing them. These bamboo forests have the additional benefits of being quick to mature, producing a regular crop which is easy to harvest; and of being CO2 sinks. I decided to try to find out how to propagate bamboo. Later I was given a bare rocky hillside for a trial area. This grew to be a demonstration of different propagation techniques with 24 species of Bamboo. The work expanded to halting landslides and teaching bamboo culture to people from other projects. Later I wrote two books, one for Nepal which is also available in Nepali, and a more recent book for wider use in warm countries. This was favourably reviewed in the December TAA Newsletter.

3.  Soil improvement.

While 1 was directing the East Taiwan Aborigines Agricultural Service Project. I discovered that the aborigines' best land had been taken over by large agricultural corporations such as the Taiwan Sugar Corporation. They cropped it with pineapples and sugar cane, using soil analysis and balanced fertiliser application, until it became uneconomical to grow crops, it was then given back to the tribal farmers. After several years rest it had become covered in 5-6 feet high razor grass.

    I wondered why the farmer was clearing poorer steeper land for cropping while not using what seemed obviously much better land? He told me 'the land is now useless! it was not only that the soil was worn out, but it was uneconomical to dig out that persistent stoloniferous razor grass. I was informed that there were many such areas of land which had been good before they had been used for commercial farming. When the fertility declined more fertiliser was used, instead of resting it as the tribal farmers would do.

    I thought that it would be good if we could rehabilitate such land, and so we agreed that we could have the land rent free for 4 years to try to improve it. After trials of herbicide to remove the razor grass we planted maize and grew a normal crop. However the second crop was very poor, so we again sowed maize applying three times the normal amount of fertiliser, but the result was even worse. We could not show other farmers what we were doing as it was too embarrassing. The land owner said he knew that would happen after the first year. I did discover how to restore the land economically and without using fertiliser by adding soil microorganisms, and later we had open days to demonstrate practical ways of soil conservation and soil improvement.

    The four areas of land I used in Nepal were all poor but different soils, all improved considerably. First I had a sloping vegetable garden with only 1 inch of topsoil at the top end. Two years later I was given the use of land in a hospital compound where the topsoil had been removed over twenty years previously. All that was growing were a few clumps of thin grass and odd thorn bushes, it looked hopeless, hard crusted bare red laterite subsoil. Farmers looking over the wall said we were wasting our time as we started to construct terraces, half terraces and bunds. We also planted grass and legume trial plots. On the slightly better area we dug out holes and planted fruit and nut trees.

    The following year we were able to lease an area of very stony waste slope land, again by the side of the road. As before we were told by passers by that it was a complete waste of time. I replied we were trying to see if the only land available to landless people could be made economically viable. For the second time in Nepal we made trials in that area, digging holes between the most stony land, adding what soil there was and planting the most likely fruit and nut trees. We planted a range of grasses and legumes and combinations and also constructing three replications each of full terraces, half terraces, contour strips and control bare slopes. Two or three years later, when showing some visitors round, two old farmers called me over to the roadside. They informed me that they had said two years before, I was a fool, that land will never be worth bothering with. Now we are amazed, we know that you have not used chemical fertilisers, nor used more compost than ordinary farmers use. If you can get as good results on this land any land could be improved. How did you do it? could you show our village? The government should be doing this kind of work, they only use good land.

    Unfortunately government regulations prevented me from working outside of the trial area for several years. Though I did advise a village project which as a result grew vegetables for sale on land previously unfit. Both areas of land were transformed, 34 kinds of fruit and nuts were planted, vegetables, field crops, fodder grasses and legumes grown well. After some years the district agricultural officer brought his staff to see our work; and later arranged for us to do soil conservation trials in nearby areas. He pointed out that the farmers were starting to dig up the contour strips the government had been promoting and so it was important to show successful methods. Unfortunately as the work was taking off my visa ran out because I do not have a degree in Agriculture.

4. The lack of research into soil improving plants and micro organisms, and into lasting soil improvement and conservation. Then applying it and relating in simple language what is found to be effective and permanent.

Most hill soils in the tropics are acid, adding fertilisers make the soil more acid and so less favourable to the beneficial soil micro organisms. Without the microorganisms the plant foods become locked up and unavailable to most plants. The result is that more and more fertiliser has to be applied to obtain the same crop yield. By adding organic matter and micro organisms to the soil the micro organisms thrive and break down and release the locked up plant foods. There has been work in the late 1930s and 40s showing that there are plants other than legumes which make nitrogen and other plants which make phosphate and potash available to crop plants, why have we not heard more of such information? Why is there not more work on sustainable land management?

    To quote from The 1992 Earth Summit at Rio which had Agenda 21 as the centre piece.

    Humanity stands at a defining moment in History, we are confronted with a perpetuation of disparities between and within nations, a worsening of poverty, hunger, ill health and illiteracy, and the continuing deterioration of the ecosystems on which we depend for our well being---

Land degradation is the most important environmental problem affecting extensive areas of land in both developed and developing countries.     A similar statement was made on 31 st of August 01 by an astronaut who is horrified at the changes in the earth seen from space since 1990.

    There is now much optimism about new varieties and new crops developed as a result of genetic engineering. Genetic Engineering is going to save the future by producing super plants which have all sorts of qualities built in, high yield, disease resistance etc. It sounds hopeful but we need to think about it. Suppose a new high yielding variety of cassava produces three times the yield of traditional varieties. Surely that means that it is taking more from the soil than the traditional varieties; so how long will it be possible to maintain the soil fertility?. We might just remember the sayings 'You can't eat your cake and still have it.' and 'you must put back what you take out'.

    Hill farmers in Taiwan know that cassava exhausts the soil, and so if possible only grow it when they particularly need money, and only grow once in 7 - 10 years.

    Unless we can reverse the loss of soil quantity and quality, the genetic engineering will only bring about a short lived yield increase; followed by worn out soil, famine, disease and war, as desperate people use desperate measures. The improved plants will still need soil, and it is no use breeding efficient plants if they die of thirst due to the lands reduced capacity to attract and retain moisture.

    My book discusses the requirements and gives a comprehensive description of methods to obtain sustainable soil and water management So allowing us to use the land in cultivation more effectively so that the need to destroy the natural habitats that plants, animals, and people need to survive is at least reduced. The livelihood of rural people will be improved, resulting in reduced need for large families, so contributing to balancing the world's population with the world's resources.

What have soil scientists been concentrating on for the last 50 years?

    The following is an abstract of a paper presented at the British Society of Soil Science Easter meeting, 31 st March 1992. by Professor Michael. Stocking of the School of Development studies University of East Anglia. Norwich, UK.

    Soil scientists claim a competence in studies of soil erosion and the practice of soil conservation. Yet Soil science has manifestly failed to relate this competence to the challenge of developing sustainable land management systems in the tropics. At best science is the passive provider of data sets, at worst it is by-passed directly. The potential demand on soil science by land managers, soil conservationists, agriculturists, rural development planners and other clients is huge. For tropical and developing countries, the key issues in land degradation and rehabilitation centre around the development of land use systems that:

1) provide the goods and services needed by land users;

2) are practical.

3) are within the resources of land, labour and capital of land users;

4) produce an acceptable economic return with the minimum of risk- and

5) ensure the maintenance of the resource base and long term productivity.

To varying degrees, the knowledge of soil scientists is applicable to all five, but sadly the provision of information has been lumpy, inadequately presented, indigestible to the user, hidebound by specialised terminology and un interpreted..

The "Good News step by step terracing system", can provide a method for two or three farmers to cooperate and stop the loss of soil and plant nutrients quickly. The process continues until all their land is developed into a fertile and sustainable system of terraces.  The"Good News multi-use level" and the"GoodNews Bulldozer conversion for walking tractors" are other developments which could be of much value in many places. Our trials and demonstrations showed that in the whole range of conditions from steep infertile landslide areas to rice paddies, there could be sustainable transformation and increase in production, the promise of a very different, but much better future for the area.