有效氮

亚高山针叶林土壤有机层有效氮动态及其对外源C、N增加的响应

Dynamics on soil available nitrogen in organic layer and its responses to carbon and nitrogen supply in two subalpine coniferous forests of western Sichuan

不同施肥处理对土壤有机质、有效氮、磷、钾、钙和镁元素含量和PH值都有不同的影响。

Different fertilization treatments have different effects on the content of organic matter , available nitrogen , phosphorus , potassium , calcium and magnesium and pH value on soil .

火烧迹地在降第一场雨后土壤pH值升高，有机质减少，全氮、全磷、钾、钙等含量减少，而有效氮、镁含量增加。

Soil pH , available N and Mg increase on burnt sites following the first rainfall , however , soil organic matter , total N , total P , K and Ca decrease .

短期培养试验中，CO2浓度倍增和不同土壤湿度下土壤全氮和有效氮的变异较小（变异系数分别是555%和384%），但可反映一定的变化趋势。

The short-term simulated experiment showed that doubled ambient CO_2 concentration and soil moisture regime had no significant effects on soil total and available nitrogen , the variation coefficients being 5.55 % and 3.84 % , respectively .

该地区一年的净有效氮矿化总量为159.23kgN·hm-2（土壤层0-15cm）。

Annual amount of net nitrogen mineralization was 159.23kgN · hm-2 ( for 0-15cm soil layer ) .

7采用差分式全球定位系统，网格法采集土壤样品，使用ASI系统研究法进行土壤有效氮和有机质含量的测试；

Directed by DGPS , soil samples were collected by certain grid in two fields and the content of soil available N and organic matter were tested by ASI soil nutrient system .

用SPSS软件进行分析表明，土壤磷酸酶活性与土壤pH、有机质、全氮、有效氮、有效磷和速效钾显著正相关，可以作为土壤肥力评价的一个指标。

Correlations were analyzed by SPSS software , and soil phosphatase activity was related positively to soil pH , organic matter , total nitrogen , available nitrogen , available phosphorus and available potassium . Soil phosphatase activity was considered an indicator for soil fertility evaluations .

土壤中的有效氮、速效磷和速效钾分别平均增加38.49%、47.55%和26.81%，同时TOC也增加了7.96%。

Meanwhile , the values of available N , P and K in soil were increased by 38.49 % , 47.55 % and 26.81 % in average , respectively . TOC was also increased by 7.96 % .

将土壤样品置于康维皿外室，硼酸吸收液于内室，利用碱解扩散法直接测定土壤有效氮，最理想的还原剂是Devarda合金。

The ideal reducing agent in soil available nitrogen tests by Conway Method is Devarda alloy .

火烧后4a内，土壤氮的含量基本都比未烧林地有所下降（中强度火烧迹地土壤有效氮含量除外）。以后有逐年增加的趋势。

Within 4 years after fire , compared with unburned site , the content of nitrogen in soil showed a light decline , except the active nitrogen of soil in moderate burned sites , and had an increasing trend year by year after 4 years .

有效氮的含量在稀土含量较低时升高，高含量时则下降，实验确定外源稀土对旱培土壤有效氮作用的无观察效应浓度（NOEC）为443.8mg·kg-1。

The contents of soil available N increase when the concentrations of REs in soil are low whereas higher levels of REs have negative effects , and the NOEC ( no observed effect concentration ) of applied REs to it is 443.8 mg · kg ~ ( - 1 ) .

土壤全氮含量平均为0.082%，有效氮含量平均为57.7mg/kg，有76.3%的土壤有效氮在30～65mg/kg之间；

The average contents of total N and rapidly available N were 0.082 % and 57.7mg/kg respectively while the contents of rapidly available N of 76.3 % soil samples were among 30 ~ 65mg / kg .

土壤中有效氮、磷、钾测定方法相关性研究

Interrelation among Determination Methods of Effective N P K in Soil

测定土壤有效氮的康维法改进

Modification of the Conway Method for Soil Available Nitrogen Testing

河北平原土壤有效氮测定方法的改进及其相关研究

A Modified Analytical Procedure for Predicting Nitrogen Supply of Soils in Hebei Plain

土壤有效氮的含量多少与有机质含量关系不明显。

The available nitrogen of soil has no significant relationship with organic matter .

该地区土壤有机质含量不高.有机质和有效氮含量偏高；

The high content of soil organic matter and available nitrogen was found .

土壤有效氮测定方法研究

Study for Measurement of Available N in Soil

评价土壤有效氮测定方法的生物指标

The biological indices for evaluation of chemical extraction methods determing available nitrogen in soils

泉州湾湿地土壤水解酶特征及其与土壤有效氮磷的关系

Soil Hydrolase and the Interaction with Available Nitrogen and Phosphorus at Quanzhou Bay Wetland

秸杆腐解过程中有效氮保护的研究

Research on Effective Nitrogen Protection in Straw Decomposition

新民市农田土壤有效氮、磷、钾含量变化分析

Evolution Trend of Soil Available N , P and K Contents in Xinmin District

细根的中位值寿命与土壤有效氮含量的季节相关性呈现明显的正相关，其与土壤有效氮垂直相关性呈现明显的负相关。

It presented significant positive seasonal correlation between MRL and the content of available nitrogen .

施氮处理后，樟树林的土壤有效氮含量存在减少的趋势。

The available nitrogen content in forest soil could decrease with the treatment of nitrogen fertilization .

滴灌随水施肥对土壤有效氮动态的影响

Effect of Fertilization through Drip Irrigation Systems on Available Nitrogen Dynamics in the Different Soil Layers

三种纤毛虫对土壤微生物量和有效氮磷含量的影响

The influence of three ciliates on soil microbial biomass and soil available N and P content

长白山原始林和次生林土壤有效氮含量对模拟氮沉降的响应

Responses of Soil Available Nitrogen of Natural Forest and Secondary Forest to Simulated N Deposition in Changbai Mountain

20%NaGl提取蒸馏法相关性都极显著，这四种方法均适用于灌漠土有效氮的测定。

All of those 4 methods are available in the analysis of available nitrogen in the irrigated-desert soil .

不同化肥施用方式对鄂西南植烟土壤有效氮时空动态的影响

Effect of Different Fertilization Pattern on Available Nitrogen Space-time Dynamic Balance of Planting Tobacco Soil in the Southwest Hubei

四川洪雅几种退耕还林模式土壤有效氮的动态研究

The Dynamic of Soil Available Nitrogen Under Several Patterns of the Coverting Lands into Forests in Hongya , Sichuan