速效磷

• The normal analytic technique was adopted to mensurate the basical nutrients such as total n , total p , total k , available n , available p , available k , organic matter , ph and so on . meanwhile , various techniques were employed to mensurate the soil dissoluble carbon , finally the technique of water saturating - h2so4 - agso4 - circumfluence - feso4 titration was used in this experiment
  测定土壤的基本养分状况全氮、全磷、全钾、速效氮、速效磷、速效钾、有机质、 ph等采用常规分析法，对土壤可溶性碳的测定方法进行了多方面的探索，最后采用水提? h _ 2so _ 4 - ag _ 2so _ 4回流? feso _ 4滴定这一方法。
• The data used in this dissertation originate from 3 regions in china - the northeast , the north china plain and the mid - lower yangtze river - and cover 6 provinces , 15 counties , and 180 sample plots . the data include information on soil fertility , quality , and corresponding socio - economic data for the households farming the sample plots . the primary soil fertility indicators analyzed are soil organic matter , total nitrogen , effective phosphorus , and effective potassium
  本文选择有机质、全氮、速效磷和速效钾4个与农作物生长发育密切相关的土壤化学指标作为土壤肥力的基本分析指标；选取东北、华北和长江中下游3个地区，包括黑龙江、吉林、北京、河北、江苏和浙江6个省份15个县市180个样本地块。
• The result indicated that straw mulching could increase soil porosity by 2 . 88 % - 5 . 76 % , reduce soil bulk density by 1 . 86 % - 3 . 73 % and the content of soil water with straw mulching was higher than that with no straw mulching treatment ( ck1 ) at different growth stage , improve water - stable aggregate ; and increase soil organic matter , available n , available p , available k , improve soil perviousness and soil retention of water and fertilizer
  研究结果表明，与对照ck1 ，相比，秸秆覆盖可使土壤总孔隙度增加2 . 88 % ~ 5 . 76 % ，土壤容重降低1 . 86 % ~ 3 . 73 % ，并且各生育期覆盖处理的土城含水量均比对照高，并且秸秆覆盖还田对促进土壤团粒结构形成具有较大作用，改善了土坡通透性和保水保肥性；同时秸秆覆盖还田使土壤有机质、全氮、速效氮、速效磷、速效钾得到明显提高，从而培肥地力。
• This research investigated the variability and the quantitative relationships among soil nutrients ( soil ph , total n , organic matter , available p ) , growth status ( spad , lai and spad lai ) and yield of rice . all data were analyzed by both classical statistics and geostatistics based on gis . by further integrating gis , gps and crop management knowledge model , a decision support system for precision farming ( dsspf ) was developed , which laid a technical foundation for the practical application of precision farming system
  本研究基于gis技术，以经典统计和地统计学为分析手段，确立了田区土壤养分(土壤ph 、全氮、有机质、速效磷、速效钾) 、水稻作物长势( spad 、 lai 、 spad * lai )和产量的空间变异特征及定量关系；进一步以作物管理知识模型为智能决策支撑，提出了gis与模型及gis与gps的组件化集成技术，构建和实现了基于田区作物产量、土壤养分和苗情监测差异的精确农作决策支持系统( dsspf ) ，为精确农作系统的应用奠定了技术基础。
• ( 5 ) the organic matter , total nitrogen , available phosphorus content were different between different land use types in 1980 and 1999 , the order of these nutrients content in different land use types was irrigated land > rained farmland > grassland in 1980 ; the order of these nutrients content in different land use types in 1999 was vegetable land > irrigated land > rained farmland ; the changes of organic matter , total nitrogen , available phosphorus content were different between different land use types from 1980 to 1999 , the order of these nutrients content change was vegetable land > irrigated land > rained farmland > grassland
  ( 5 ) 1980年，土壤有机质、全氮、速效磷三种养分含量在旱地、水浇地、荒草地三种用地类型间的变化规律是水浇地旱地荒草地，而速效钾含量在三种用地类型之间的变化规律为旱地水浇地荒草地。 1999年，土壤有机质、全氮、速效磷含量在不同用地类型之间的变化顺序为菜地水浇地旱地；而速效钾含量的变化顺序却为旱地菜地水浇地。
• Though the study on the long - term of no - tillage and ridge culture in this dissertation , the research results are as follows : 1 ) nt can change the wee terrain and change the conditions of air and water , which leads to the seasonal fluctuation of the main kinds of microbes such as bacterica , foungi , azotobacter and cellulose decomposing bacteria
  3 ，聚土垄作（包括冬水垄作、兔耕垄作、免耕厢作）的平均增幅为156 2 ，有机质和速效氮也有同样的趋势；全磷和速效磷、全钾和速效钾随作物的种类、生长周期、水分和气温的变化而变化。
• ( c ) land natural productivity increase from 7843 kg / ( hm2 - a ) to 17335 kg / ( hm2 - a ) relate to altitude closely , and the mean rate of enhancing yield is 23 . 53 percent in this region with annual enhancing - rate of 0 . 64 percent in last 15 years . ( d ) there are many facters that have been influe ncing soil effective coefficient that ' s soil organic matter , total nitrogen , effective phosphine and soil texture in turn . in a word , attenuation cause of land productivity is the result of water and soil . ( e ) the forestland potential productivity change from 3986 kg / hm2 to 15034 kg / hm2 , but it has a high distinction between southern aera and north area in yaan city . ( f ) the grassland potential productivity increase from 4085 kg / ( hm2 - a ) to 16973 kg / ( hm2 - a ) , but it has a high classification of potential productivity , ( g ) ditribution map was formed of potential land productivity . ( h ) it could be act as decision support for agriculture development , national land planning and ecotop constructive , etc
  5 、土地自然生产潜力水平的主要土壤限制因素为有机质、全氮，其次为速效磷和土壤质地；区域潜在生产力差异的制约因素，主要为土壤，次为水分，水、土两项衰减合计为45 . 99 ，石棉、汉源两县水、土衰减达到60左右。 6 、林地潜力在3986 15034kg / hm ~ 2之间，高等级林地比重小，以大相岭为界，北部的各县林地生产力水平高，南部的两县林地生产力水平较低。 7 、天然草地生产潜力水平高，潜力在16973 4085kg / ( hm ~ 2 ? a )之间，以高产的一、二、三级草地为主，且近10年来该比例变化不大。
• 2 . soil properties varied sharply , with available potassium showing the highest cv ( 106 % ) , available iron the relative higher ( 98 . 5 % ) , and soil ph the lowest ( 12 . 9 % ) , with others the medium values . cv of total nutrients did not change greatly , which meant total nutrients are stable
  养分的变异系数范围在12 . 9 106之间，速效磷的变异系数最高，为106 ，有效铁的变异系数也较高，为98 . 5 ， ph值的变异系数最低，为12 . 9 ，其它大多数养分的变异系数属中等强度变异。