Soil healthcare is fundamental to sustainable agriculture. Ideal soil heath care includes provision of optimum soil reactions, soil moisture content and addition of organic matter. All these factors aid in improving soil fertility and hence lead to the evergreen revolution. Vermiculture, green manures and bio-fertilizers enhance soil fertility and maintain its sustainability.
Crop diversification is the most important factor in enhancing production and maintaining sustainability on all fronts. Crop diversification methods like crop rotation, mixed cropping and intensive cropping are required to improve soil fertility, enhance yield, reduce erosion and the need for chemical fertilizers.
Crop diversification methods
Crop rotation: The practice of growing different crops in succession on a piece of land is called crop rotation. The basic aim of crop rotation is to maintain soil nutrient balance. It will also ensure maximum profit with least investment.
Mixed cropping: It is growing of two or more crops together in the same piece of land. One of the most important advantages of mixed cropping is that even under adverse conditions all the crops do not get destroyed. For example gram with wheat or pigeon pea with jowar.
Intensive cropping: A situation where a number of crops are grown simultaneously in the some piece of land in one agricultural year. It can be achieved by multiple and relay cropping.
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Radio direction finding is the
Radio direction finding is the technique of measuring radio wave angle of arrival (AOA.) A transmitting antenna radiates radio energy toward the direction finding site. At distances greater than ten wavelengths from the transmitting antenna, the radio wave can be represented as a plane wave, with linear contours of constant amplitude perpendicular to the direction of propagation. Ideally, the radiated sharepoint hosting energy propagates along the most direct path from the transmitter to the receiver. The receiving system is conventionally called a direction finder, or DF for short. A direction finder employs one or more antennas in a DF array, used to detect the incoming radio wave. The output of each antenna is applied to a radio receiver, and this signal is sampled and input to a DF computer processor for determining AOA. The DF processor may either (1) determine the direction of energy flow toward the direction finder, (2) measure the direction of maximum rate of phase change across the DF array, or (3) estimate the direction of the velocity vector, normal to the plane wave fronts. A well-known ftp hosting example of a simple DF system, which is still in use, is a rotatable loop antenna connected to a radio receiver. AOA is measured by determining the direction of energy flow toward the DF antenna. This is accomplished by rotating the loop for minimum audible output as indicated by the headphones, and thereby placing the null response of the loop on the AOA of the received signal. Thus, the direction to the transmitter is indicated by the broadside angle of the loop. The loop also has a null response on the reciprocal bearing, 180◦ from the true AOA. This problem of ambiguity can be resolved with an auxiliary “sense antenna.” The advent of radio communication in the late 1890s launched the asp web hosting development of direction finding techniques for navigation and radio transmitter location. Radio navigation and radio location are complimentary technologies exploiting a common methodology. For example, signals received at sea from known shore-based radio beacons are used for navigation by triangulation to fix the position of a ship. Conversely, two or more direction finders at known locations can be used to locate a radio transmitter by triangulation.