Influences on Soil Nitrogen Mineralization: Implications for Soil Restoration and Revegetation
Introduction
Nitrogen is a macronutrient essential to the growth of plants and is also one of the most deficient nutrients in most soils. Insufficient levels of available soil nitrogen limit microbial growth and decay and growth of the plants themselves. Because site disturbance adversely affects the flow of nitrogen through soil-plant-microbial systems, the re-establishment of the cycle of nitrogen flow in the soil is crucial to revegetation attempts. Mineralizable nitrogen--nitrogen in forms readily usable by plants--is dependent upon a number of factors. According to Stanford and Smith (1972), those factors include soil moisture, pH level, temperature, microbial biomass, and amounts of other nutrients. Three of the more significant and interrelated influences--microbial biomass, temperature, and moisture--are discussed here. This is certainly not an exhaustive list of factors influencing soil nitrogen mineralization, but instead, a general overview of the more significant considerations.
Microbial Processes
Microbial decay of organic material is the main release process of soil nitrogen. Nitrogen is released from microbial decay in the form of ammonium, but can also be immobilized by microbes which take up nitrate and ammonium to satisfy their own requirements. The mobilization or immobilization of nitrogen is dependent upon the amount of N the decomposing material itself provides; insufficient nitrogen released from decaying organic matter will result in the absorption of ammonium and nitrate by the microbes. An excess of N will satisfy the requirements of the microbes and provide a surplus to be released into the soil...
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The play is set at the back porch of a house in Chicago .It starts off when Robert wakes Catherine up at 1am past midnight, because it is Catherine’s 25th birthday. They decide to celebrate Catherine’s 25th birthday by having champagne that was lying on the table behind Robert. They have the typical birthday conversation a normal father-daughter would have.
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... campus but at camp too. Another exceptional display of leadership during the semester was by our cadre. Handling certain situations that arose over disputes between cadets or amidst the government shut down conveyed to myself the skills taught in ROTC like mental agility and innovation happen daily. For instance, configuring multiple plans to continue through with a fall FTX for the MSIII. Reinforcing my trust within my cadre to best prepare my peers and myself to excel both at camp and during our careers in the U.S. Army.
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William Shakespeare’s Macbeth tells the story of a general who commits regicide in order to become king. Early in the play, Macbeth is conflicted as to weather or not he wants to kill his kinsman the king. In the first two acts Macbeth is not portrayed as a ruthless killer; he is a sympathetic character who succumbs to the provocation of his wife and a prophecy foretold by three mysterious witches. In contrast, Lady Macbeth is a manipulative, immoral woman. Her ambition is so strong that she is willing to do anything to see her husband succeed. However, in the third act things begin to change. The death of the king and lord and lady Macbeth’s rise to power catalyze profound transformation in their personalities.
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