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8085 MICROPROCESSOR RAMESH GAONKAR NOTES
THE NOTES OF MICROPROCESSOR 5TH SEM ETC
MD ALI HASNAIN
abc Institute
Trebuchet
A trebuchet is a type of catapult that uses a swinging arm to throw a projectile. It was a common powerful siege engine until the advent of gunpowder. There are two main types of trebuchets. The first is the traction trebuchet, or mangonel, which uses manpower to swing the arm
Arun Thomas
Introduction of refrigeration
To study about the introduction of refrigeration
Yerraboina Srikanth
Asclepius Consulting
Asclepius Consulting is a case in the course of Sales Management which is taught across premier B-Schools across India. This presentation captures the vital points given in the case and also answers a few relevant questions.
Satyaki Kundu
MATHS 3-SEMISTER Question Paper
MATHS 3-SEMISTER Question Paper
Anirudh Pareek
Workforce Employment Issues pt.4
The objective of this chapter is to elaborate on the concept of workforce employment issues. These methods will assist students to understand the concept of workforce employment issues.
Divya Bhatt
Cellular system design and Frequency reuse
Cellular system fundamentals, Frequency reuse , Channel assignment strategy and Handoff strategies explained
Jayanth Jastin
UNIX PROGRAMMING R16 OCT 2018
Reference purpose
Sivasai Lella
Sample paper of Business Environment
Sample paper
Rishika Jain
Transmission Lines objective type questions
Transmission Lines objective type questions
Last 10 years question bank for 2nd year mbbs.
Get access to all the relevant questions for forensic medicine and help yourself score better.
Srijita Mandal
Drought and its Types in Agriculture
Droughts and Drought ManagementDrought is a climatic anomaly, characterized by deficient supply of moisture resulting either from sub-normal rainfall, its erratic distribution, higher water requirement or a combination of all these factors. Understanding mechanisms of plant adaptation under severe water stress is very essential. Adaptation of rainfed crops to the changing environment is assessed on the basis of stability in yield over years. The factors contributing to the yield stability of any crop are root system, morphological characteristics, stomatal mechanisms, metabolic adaptation, canopy architecture and drymatter partitioning (Gangadhar Rao et al., 1999). The National Commission on Agriculture (Anon., 1976) categorized droughts into three types, viz., 1.meteorological, 2.hydrological and3.agricultural drought. Meteorological drought is the negative departures of kharif rainfall in different parts of the country. Hydrological drought is the extended dry period leading to marked depletion of surface water and consequent drying up of reservoirs, lakes, streams, rivers, cessation of spring flows, and depletion of ground water levels. Agricultural drought refers to extended dry period in which the lack of rainfall results in insufficient moisture in the root zone, causing adverse effects on arable crops. The spatial and temporal variations in such droughts are of paramount importance particularly when it occurs at any critical phenological stage of a crop.Agricultural drought is said to occur when the actual evaporation (AE)/ potential evaporation (PE) is <0.25 at the critical phenological stage of the crop. The critical stages in case of pearlmillet are tillering, flowering and grain formation stages.The studies on probabilities of meteorological droughts in different regions of the country were reviewed by Singh and Ramana Rao (1988) based on their occurrence from 1875 to 1987. They observed that about 70% of the geographical area was affected during the disastrous drought years, 1918 and 1899. Though the worst drought of 1987 had affected over 83% of area till the end of July, the good rainfall received in the following month (August) had saved the crops. Thus the impact of droughts on our food production could be minimized through later rains together with improved kharif and rabi crop management strategies.Drought managementThe risk involved in successful cultivation of crops depends on the nature of drought (chronic and contingent), its probable duration, and periodicity of occurrence within the season. In the arid region where mean annual rainfall is less than 500 mm, drought is almost an inevitable phenomenon in most of the years (Ramakrishna, 1997). In semi-arid region (mean annual rainfall 500-750 mm), droughts occur in 40 to 60% of the years due to deficit seasonal rainfall or inadequate soil moisture availability between two successive rainfall events. Even in dry sub-humid regions (annual rainfall 750-1200 mm), contingent drought situations occur due to break in monsoon conditions. Therefore, drought management strategies need to be identified separately for each climatic region and for each major crop. Types of agricultural droughtsCrop production in rainfed areas is generally affected by five distinct categories of drought, viz., early season, mid-season, late season, chronic and apparent drought (Rao, et al., 1999).• Early season drought generally occurs either due to delayed onset of monsoon or due to prolonged dry spell soon after the onset, resulting in seedling mortality, need for re- sowing or poor crop stand and seedling growth. The early withdrawal of monsoon results in reduced water availability period for crop growth. Thus, the crops suffer from acute shortage of water during reproductive stage.• Mid-season drought occurs due to inadequate soil moisture availability between two successive rainfall events during crop growth. Its impact depends on crop growth stage, duration and intensity of the drought spell.• Late season or terminal drought occurs as a result of early cessation of monsoon, mainly during the years with late commencement or weak monsoon activity. Terminal droughts are more critical as the crop yield is strongly related to water availability during the reproductive stage. Rainfed rice in dry sub-humid regions is often subjected to terminal droughts due to failure of September rains with 40 to 50% of dry spells of over 5 days during that month.• Chronic drought is common in arid areas where rainfall and stored soil moisture are inadequate to meet crop water requirement during most of the years. Here, the assured growing period is hardly 6 to 7 weeks. These are characterized as chronic drought or highly drought prone areas.• Apparent drought conditions are observed in low to medium rainfall regions due to mis-matching of the cropping pattern in relation to rainfall / moisture availability.
Yimpangakum Imsong