In this backdrop, those who deal to protect and improve the natural environment including rivers, lakes, forest and wildlife should deeply concern the environmental challenges and the possible remedies. The unique design of nature has provided scavenger species, which keep the environment free of such wastes. In the countries which have long been the seat of civilisation it is not always a simple matter to reconstruct the "original" vegetation. But this can usually be done with a fair degree of certainly when sufficient detailed knowledge of the behavior of the native plants and communities they forms has been obtained and a comparison made with neighbouring countries having a similar climate and flora, but perhaps with different methods of forestry and agriculture. On the other hand, man is always unwittingly performing ecological experiments on a small or large scale, experiments which the ecologists can watch and the result of which he can trace out and record, thus slowly gaining an extensive knowledge of the capacities of plants, of their reactions to changed conditions, which the observer in a "virgin country" cannot easily acquire. It is that the farmer, landowner, or "local authority" sometimes carries his experiments further than the ecologist would desire. The observation of the process of recolonisation of a piece of cleared land, for instance, many be rudely interrupted by digging for grave, road-making or building. Interesting and instructive bits of vegetation are often destroyed by some fresh outburst of energy on the part of "higher powers", all the move irritating when it is clearly not wisely directed. But the observer who can put up with such disappointments, and who will never lose an opportunity of observing and comparing what is going on, can leave a great deal if he will adapt himself to the conditions of the countryside in which he lives.
