I am glad you guys are starting to take an interest in the little ocean Islands; I have been pushing for more work in these areas for years now, here is an extract copy of a letter I wrote to our Minister of Foreign Affairs in April 05:
“The NZ govt has agreed to support Niue and now Puka Puka in its efforts to rehabilitate these tiny Islands. The Island of Niue, 260 square kilometres in size has 4,108 ha of arable land of which 470 ha are, or were in permanent crops. For sustained viability, this land and the surrounding marginal land will need stabilising to prevent soil loss and runoff. This can only be done in the tropics using the vetiver system of hedges which, once established, is permanent and cheap.
Ocean Islands depend on rainfall to replenish their aquifers. In their natural state, these little Islands had some jungle cover which provided fuel wood and building material, but more importantly the jungle’s undergrowth spread the rainfall run-off out, slowed it down, gave it a chance to seep in and replenish the natural aquifers before it ran in to the sea.
These jungles and especially the undergrowth have been destroyed in recent years. With greater population pressure, gardens which used to produce sufficient food to mix with the fish and shell fish from the reef and lagoons are now producing little. Run-off is uncontrolled and where it enters the sea, polluted, it kills the reef. Not only are food stocks going down but fish stocks are diminishing also. Where the reef is damaged, there is no protection from the next hurricane, and the waves can now be devastating.
In their present state, these islands can be supplied with food and infrastructure, but we cannot supply them with sufficient water, nor keep up the supply. Rainfall must be controlled so that it doesn’t runoff and is wasted; this is the only way to ensure water supplies to these little islands and keep them habitable.
Vetiver hedgerows can be very valuable in preventing erosion and water damage within housing areas, and in protecting roads. The hedgerows should be coupled with urban tree planting in housing areas, which could serve as shade as well as a source of food, fuel or forage. When planted along embankments and in catchment areas, vetiver hedgerows can also reduce erosion of roadsides. If there are streams in the country, the hedgerows are also extremely important in reducing stream bank erosion and sediment loads in streams and harbors. The massive root system of vetiver (measured down to six meters in Thailand) forms an extremely dense underground bio-dam along the contour or across the slope, and is capable of clarifying water and not only maintaining but increasing year around water flow of springs and streams.
By periodic pruning of the hedgerows, vetiver can provide voluminous amounts of mulch for composting to improve soil texture and carbon content in the natural terraces formed behind the hedgerows. Old-growth from vetiver hedgerows makes excellent thatching can be used for compost; however, young regrowth is tender and makes good livestock feed.”
The vetiver system is the only system that will give these little ocean islands any chance of survival, lets really work on somebody to get an Island for demonstration purposes.