Read the passage given below and answer the questions that follow: A conservation problem is equally important as that of soil erosion is to loss of soil fertility. Most agriculture was originally supported by the natural fertility of the soil; and, in areas in which soils were deep and rich in minerals, farming could be carried on for many years without the return of any nutrients to the soil other than those supplied through the natural breakdown of plant and animal wastes. In river basins, such as that of the Nile, annual flooding deposited a rich layer of silt over the soil, thus restoring its fertility. In areas of active volcanism, such as Hawaii, soil fertility has been renewed by the periodic deposition of volcanic ash. In other areas, however, natural fertility has been quickly exhausted. This is true of most forest soils, particularly those in the humid tropics. Because continued cropping in such areas caused a rapid decline in fertility and therefore in crop yields, fertility could be restored only by abandoning the areas and allowing the natural vegetation to return. Over a period of time, the soil surface would be rejuvenated by parent materials, new circulation channels would form deep in the soil, and the deposition of forest debris would restore minerals to the top soil. Primitive agriculture in such forests was of shifting nature: areas were cleared of trees and the woody material burned to add ash to the soil; after a few years of farming, the plots would be abandoned and new sites cleared. As long as populations were sparse in relation to the area of forestland, such agriculture methods did little harm. They could not, however, support dense populations or produce large quantities of surplus food.Starting with the most easily depleted soils, which were also the easiest to farm, the practice of using various fertilizers was developed. The earliest fertilizers were organic manures, but later, larger yields were obtained by adding balanced combinations of those nutrients (e.g. Potassium, nitrogen, phosphorus, and calcium) that crop plants require in greatest quantity. Because high yields are essential, most modern agriculture depends upon the continued addition of chemical fertilizers to the soil. Usually, these substances are added in mineral form, but nitrogen is often added as urea, an organic compound.Early in agricultural history, it was found that the practice of growing the same crop, year after year in a particular plot of ground not only caused undesirable changes in the physical structure of the soil but also drained the soil of its nutrients. The practice of crop rotation was discovered to be a useful way to maintain the condition of the soil and also to prevent the build- up of those insects and other plant pests that are attracted to a particular kind of crop. In rotation systems, a grain crop is grown in the first year, followed by a leafy vegetable crop in the second year, and the third usually contains legumes as they can restore nitrogen to the soil through the action of the bacteria that live in nodules of their roots.In irrigation agriculture, in which water is brought in, to supply the needs of the crops in an area with insufficient rainfall, a particular soil management problem that develops is the salinization of the surface soil. This most commonly results from inadequate drainage of the irrigated land; because the water cannot flow freely, it evaporates and the salts dissolved in the water are left on the surface of the soil. Even though the water does not contain a large concentration of dissolved salts, the accumulation over the years can be significant enough to make the soil unsuitable for crop production. Effective drainage solves the problem; in many cases, drainage canals must be constructed and drainage tiles must be laid beneath the surface of the soil. Drainage also requires the availability of an excess of water to flush the salts from the surface of the soil. In certain heavy soils with poor drainage, this problem can be quite severe, for example large areas of formerly irrigated land in the Indus Basin, in the Tigris Euphrates region, in the Nile Basin, and in the Western United States, have been seriously damaged by salinization.Choose the correct answer from the options given:1). Natural fertility exhausts most quickly in ------ (a) river valley lands. (b) humid tropical forest lands. (c) volcanic areas. (d) river basins.2). The areas most prone to heavy salinization are: --------------- (a) those irrigated with plenty of well water. (b) those in which crop rotation is practised (c) sub-tropical forests with shifting cultivation (d) poor drainage system in heavy soils.3). Crop rotation helps to i) increase the farmers seasonal income ii) preserve soil condition iii) desalinize the soil iv) destroy pests a) i, ii, iii, and iv b) i, ii and iv c) ii and iv d) ii, iii and iv4). Which of the statements is/are not true. i) Volcanic ash maintains soil fertility. ii) Annual flooding decreases soil fertility iii) In forest soils of humid tropics, the fertility decreases with time. iv) Growing different crops always increases soil fertility. a) i, iii and iv b) i , ii and iv c) ii and iii d) ii and iv5). The best possible solution for salinization is a) shifting agriculture b) crop rotation c) drainage system which is effective d) adding manure and fertilizers to the land6). The best and natural way of supplying Nitrogen to the crop is by a) adding urea b) adding chemical fertilizers c) planting a pasture crop or legumes d) adding organic manures7). Study the pictures given below carefully and choose the option that suits bestThe pictures above are the best examples for (i) crop rotation (ii) shifting cultivation and organic cropping (iii) crop rotation and shifting cultivation (iv) organic/ chemical cropping (a) option i (b) option ii (c) option iii (d) option iv8). (a) With wrong farming methods we turn fertile land into desert. Unless we go back to organic farming and save the soil, there is no future. Jaggi Vasudev(b) Agriculture is the foundation of the manufacturers, since the productions of nature are the materials of art. Edward Gibbon(c) If everybody switched to organic farming, we couldn’t support the earth’s current population. Neena Fedoroff(d) Farming is not just growing crops, it’s about cultivation of human beings. Masanobu Fukuoka