Dissertation > Excellent graduate degree dissertation topics show

Research on Effects of Nitrogen and Phosphorus of Disposing the Waste on Large-Scale Breeding Farm

Author: WangBo
Tutor: BianXinMin
School: Nanjing Agricultural College
Course: Crop Cultivation and Farming System
Keywords: large scale farm solid waste planting breeding nitrogen and phosphorus fecal returning field
CLC: X713
Type: Master's thesis
Year: 2008
Downloads: 168
Quote: 2
Read: Download Dissertation

Abstract

The waste of farm(feces) is an important factor which plagues the sustainable development of agriculture,its output has been far greater than the emissions of industrial waste and it has become a major source of the pollution in China’s rural areas.This experiment is studying the physiological tolerance of different crops,dynamic monitoring nitrogen and phosphorus of the water covers the rice field,analyzing the ability of processing the farm waste of different crops by determining and estimating the losses and loss rate of the nitrogen and phosphorus,comparing the ability of different crops of processing farm waste(feces) during filling the farm waste(feces) to rice field.In order to deal with the abundant waste in the large-scale farms.This experiment provides a basis for large-scale farms waste-treatment,and avoids the environmental problems caused by their reckless emissions and excessive filling of the waste to rice field.We get following conclusions through this experiment:1.Barley,rye and Pennisetum what are used as forage have not shown being victims at the highest volume of excreta disposal.The pot rice in P7 is the only victim(when the pig manure capacity is 300000 kg/hm~2).2.In a certain range,with the increase of manure amount applied to crops,the absorption of nitrogen and phosphorus of crop plants increases,but the amount of nitrogen and phosphorus absorption between the adjacent processing is almost the same,with the amount of manure applied multiplied Increase the loss of nitrogen and phosphorus multiplied increase,the loss rate of nitrogen and phosphorus increase as well.Through the comprehensive consideration of these factors,we find that the processing of pig manure to barley should be controlled from 15000 kg/hm~2 to 60000 kg/hm~2.Cow dung Should be controlled from 18750 kg/hm~2 to 150000 kg/hm~2.The amount of pig manure to Ryegrass processing should be controlled from 15000 kg/hm~2 to 60000 kg/hm~2,the amount of cow dung to Ryegrass processing should be controlled from 18750 kg/hm~2 to 150000 kg/hm~2. The amount of pig manure to Pennisetum processing should be controlled from 15000 kg/hm~2 to 60000 kg/hm~2,the amount of cow dung to Pennisetum processing should be controlled from 24465 kg/hm~2 to 48930 kg/hm~2.The amount of pig manure to rice processing should be controlled from 15000 kg/hm~2 to 60000 kg/hm~2,the amount of cow dung should be controlled from 24465 kg/hm~2 to 48930 kg/hm~2.3.With the amount of manure to crops increase,the content of nitrogen and phosphorus in the soil,the residue of nitrogen and phosphorus in the farming stratum increases, especially for the maximum handling and neighboring handling comparison,increase significantly.Both pot and field experiments indicate that once the application of nitrogen and phosphorus are multiplied,the loss of nitrogen and phosphorus are multiplied,so the excessive use of manure will inevitably increase the risk of environmental pollution.After abundant application of organic fertilizer(manure)for two consecutive quarters compare the amount of nitrogen and phosphorus farming stratum(soil depth 30 cm-50cm),it shows that the amount of next quarter is just like first quarter,the increase is not obvious,This may specify that the amount of nitrogen and phosphorus Infiltration slightly.4.In the point of environmental view,nitrogen and phosphorus are the important factors what cause eutrophication of water.With the increasing amount of applied manure,the amount of nitrogen and phosphorus in the water of rice fields increase significantly,and this is a potential foe of the surrounding waters and groundwater.By the dynamic study of nitrogen and phosphorus of Rice field surface water we find that there is peak of nitrogen and phosphorus content of the water after about 15 days of the application of manure,after then it decreases,so it is the critical period to control the loss of nitrogen and phosphorus when it is 15 days after fertilizing manure to crops.5.When the nitrogen application is almost the same,the loss amount is nitrogen Rice＞barley＞Pennisetum＞ryegrass in large field,it shows that the effect of waste disposal is rice＜barley＜Pennisetum＜ryegrass.

Related Dissertations

CLC: > Environmental science, safety science > Processing and comprehensive utilization of waste > Processing and comprehensive utilization of agricultural waste > Livestock
© 2012 www.DissertationTopic.Net Mobile