In a dry area it may be sensible to increase surface storage to improve crop yield in most years, but in a wet year this could cause waterlogging and reduce the yield. Agrostological Measures — Planting grass in heavily eroded areas is called an agrostological measure. An important component of the system is an ox-drawn wheeled tool bar, which can be used with ridgers to form the raised bed and also later for carrying precision seeders or planters Plate 5. These methods, developed for regions with winter rainfall, may not be suitable for the semi-arid tropics. As well, these crops may result in the soil being inadequately protected by vegetation from rainfall and snowmelt erosion for extended periods of the year. Ridges warm up and dry out quickly. This practice keeps soils anchored in place rather than having bare ground exposed to wind and water.
Shanan and Tadmor 1979 quote the following average run-off yield from 100 mm annual rainfall: Less than 0. · Smooth slopes are an advantage where large mechanized farming can be made more convenient by constructing all the terraces parallel and of equal width. Maintaining the correct value of soil pH, is thus essential for soil conservation. Deep-rooted crops should be rotated by shallow-rooted crops. Soil erosion has been continuing over, such a large part of India for such a long time that it has assumed alarming proportions.
Fertilizers Not all fertilizer products are effective for conservation efforts. During the season an additional 200 mm of water results in good crops on the pans, so that the installation costs can be repaid in three to five years. Conservation Practices Soil conservation practices are commonly used in during harvesting and replanting operations. There are natural occurrences, like storms, that cause their fair share of erosion problems. Biodiversity relies on soil at all times. Large catchment areas are more likely to have places where there is temporary storage of run-off in surface depressions. This a1lows double cropping instead of the traditional practice of the vertisols lying fallow during the monsoon, and only being cropped in winter on the stored moisture.
They are also known collo- quially as 'one-day soils' because they are difficult to cultivate when dry and hard, and also unworkable when saturated and sticky, but they do have a short window while drying out when the moisture is just right for cultiva- tion. Conservation approaches are a benefit to individual communities and the entire Earth. Reduction Of Impervious Surfaces — Driveways patios and paved pathways allow precipitation to flow freely off them. This is especially important in areas where rivers exist. Soil under a vegetative cover is saved from erosion due to wind as this cover acts as a wind barrier.
These organisms boost soil fertility and help in soil conservation. Excessive deposition of salts in the soil makes it unsuitable for plant growth. It will be almost impossible to support the animal and human life without land. The soil then ends up in aquatic resources bringing in pesticides and fertilizers used on agricultural land. In addition to the vagaries of rainfall, there are a host of other variables, the soil, the land use, the farming system, and the social patterns. The situation is similar in Ethiopia Plate 5. The possibility of increasing run-off through surface applications of bentonite or sediment from tanks was possible but unlikely to be economic.
As the roots of trees spread deep into the layers of soil, they hold it tightly, thus preventing soil erosion. Broadly categorizing there are two methods of soil conservation. The almost-omnipresent soil is taken for granted. The mica-laden melt waters from the glaciers of the Himalaya are used to build up the physical volume of soil by spreading the water onto gravel beds. Both engineering and biological methods have been used to check the soil erosion but it is still without a plausible check.
The experience in Africa has been well summarized by El-Swaify et al. Personal constraints are that people naturally do not like to put a lot of effort into schemes which have a low success rate, nor if their tenure is insecure. Using beneficial soil organisms like earthworms, helps in aeration of soil and makes the macro-nutrients available for the plants. Mulch also serves as a good source of nutrients for plants and helps them sustain in times of drought and dry weather. The process of tilling is beneficial in mixing fertilizers in the soil, making rows and preparing the surface for sowing.
The intensive production of and vegetable crops has further reduced organic matter levels, damaged soil structure and led to severe soil erosion on sloping land. It is done to prevent the accumulation of pathogens, which occur if the same plants are grown in the soil, and also to avert depletion of nutrients. The soil must therefore have sufficient soil moisture storage capacity to keep the crop growing between run-off events. Afforestation: The best way to conserve soil is to increase area under forests. These are native crop options that enhance the soil.