【作者】 裴立新；

【导师】 胡立勇； 王亚莉；

【作者基本信息】 华中农业大学 ， 农业推广， 2008， 硕士

【摘要】 近年来,农业生产上大量施用化肥而忽视有机肥投入的现象非常普遍,这不仅降低了肥料的利用率和施用效益,加剧土壤养分失衡,而且污染地下水,降低农作物品质,影响农作物的可持续生产和生态环境安全。本研究对信阳不同土地利用形式下土壤养分进行了测定,为信阳测土施肥、平衡施肥提供理论依据和实践指导。主要结果如下:1.土壤有机质含量是土壤肥力分级的重要指标和肥力高低的综合表现。信阳不同土地利用形式土壤有机质水平较低,其中绿化带、旱地、稻田、茶园有机质含量分别为9.9g/kg、14.8g/kg、17.6 g/kg和16.3g/kg,因此有必要加大有机肥的投入,提高土壤有机质含量。2.信阳不同土地利用形式下土壤速效氮含量分布不同,其中绿化带速效氮含量较低,平均为33.4mg/kg,缺乏严重,绿化带土壤样品的88.1%处于极低或低水平;旱地土壤和稻田土壤速效氮含量分别为中等偏低和偏高,平均含量分别为90.6 mg/kg和104.6 mg/kg,旱地和稻田土壤中速效氮含量处于中等水平的分别占各自样品的62.5%和64.0%,而旱地缺氮占31.3%;茶园土壤中速效氮水平较高,平均含量为169.7mg/kg,占整个样本的94%处于高或极高水平。因此,在氮肥的施用上要根据土壤中氮素的情况进行针对性施肥。3.信阳不同土地利用形式下土壤速效磷的分布极不均衡。绿化带土壤缺磷严重,平均含量为18.6mg/kg,有51.5%的土壤样品缺磷;茶园土壤平均为35.8mg/kg,51.6%处于极低和低水平,磷素营养缺乏,38.7%处于高和极高水平,磷素较丰富;稻田土壤平均为42.3mg/kg,处于极低和低水平的分别占整个样品的20.0%和24.0%,处于高和极高水平的占16.0%和15.0%,旱地土壤平均为46.5mg/kg,缺磷土壤占整个样品的37.5%,而56.3%的土壤磷素较高。4.信阳市土壤速效钾含量处于中等偏高水平,大部分土壤钾素并不缺乏。其中绿化带、旱地、稻田、茶园含量分别为136.9 mg/kg,90.6mg/kg,104.8mg/kg和119.5mg/kg.更多还原

【Abstract】 In the past few years,the role of organic fertilizer in agronomic practices has long been replaced by chemical fertilizer.It has also brought about some unfavorable results. Besides the impairment of soil environmental and vegetable quality in protected field,this practice also caused a decline in soil productivity through excessive soil erosion,nutrient runoff,imbalanced nutrient,and deteriorated soil chemical properties.Since the human activities vary greatly with the different land use type,it is important to assess the soil nutrient quality under the different land use types.Xinyang,a city in south of Henan province,is suffering the huge changes in land use.Unfortunately,the effects of such changes on the soil nutrient still remain unknown.Through the investigation on 4 land-use types,which include the vegetable field,paddy field,tea garden,greenbelt,280 soil samples for organic matter,available nitrogen,available phosphorus and available potassium were obtained.The results are summarized as follows:1.Soil organic matter content is low in different land-use types.So it is necessary to increase the application rate of organic fertilizer,which increases the organic matter content in soil of Xinyang City.The average content in green belt,vegetable field,paddy soils and tea garden soils were 9.9、14.8、17.6和16.3mg/kg.2.The difference of soil available nitrogen content in 4 different land-use types is obvious.The average content in green belt,vegetable field,paddy soils and tea garden soils were 33.4,90.6,104.6 and 169.7mg/kg.88.1%of the soil in greenbelt is deficient in soil available nitrogen content,which in vegetable field is 31.3%,but available nitrogen content of most soil in vegetable field and paddy field is moderate,which in percent is 64.0%and 62.5%,over 94%of the soil in tea garden is high in soil available nitrogen content.Therefore,we should consider the difference of available nitrogen content in different land-use types to use nitrogen fertilizer.3.The difference of soil available phosphorus content in 4 different land-use types is obvious.The average content in green belt,vegetable field,paddy soils and tea garden soils were 18.6,35.8,42.3 and 46.5mg/kg.Much soil deficient in available phosphorus content,which in greenbelt is 51.5%,in tea garden is 51.6%,in vegetable field is 37.5%, paddy field is 44.0%,but 38.7%in tea garden,56.3%in vegetable field and 29.0%in paddy field is rich in available phosphorus content. 4.The content in available potassium in Xinyang soil is in moderate and high level, most soil sample is not deficient in K.The average content in green belt,vegetable field, paddy soils and tea garden soils were 136.9,90.6,104.8 and 119.5mg/kg更多还原