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1.
片麻岩新成土中氮素淋溶迁移的模拟研究 总被引：3，自引：1，他引：2
采用室内土柱模拟的方法,研究片麻岩新成土中不同肥料、不同施氮量对氮素垂直运移的影响。结果表明,随着施氮量增加,硝态氮和铵态氮淋溶浓度增大,氮素淋失量增多。中等施氮量下施用有机无机混合肥可以减少氮素淋失。尿素、有机无机混合肥、氮磷复合肥中硝态氮淋失总量比值为671∶583∶629。尿素硝态氮淋失率平均为29.0%,氮磷复合肥硝态氮淋失率平均为27.8%,有机无机混合肥硝态氮淋失率平均为23.7%。随着土层深度的增加,60cm处和90cm处硝态氮淋失量差异不显著,两处硝态氮淋失量比值为1∶1.03,铵态氮的淋失量增加显著,两处铵态氮淋失量比值为1∶2.4。在片麻岩新成土壤地区,土壤培肥应本着少量多次原则。 相似文献
2.
采用室内土柱模拟的方法,研究河北省太行山片麻岩新成土中不同肥料、不同施氮量对硝态氮垂直运移的影响。结果表明,尿素、有机无机混合肥、氮磷复合肥中硝态氮淋失总量比值为1∶0.87∶0.94。中等施氮量下,有机无机复混肥可以降低氮素淋失。尿素硝态氮淋失率平均为29%,氮磷复合肥平均为27.8%,有机无机混合肥平均为23.7%。60 cm和90 cm处硝态氮淋失量比值为1∶1.03,差异不显著。淋溶结束后,有机无机混合肥在不同土层各处理中硝态氮含量最高,尿素硝态氮含量最低。 相似文献
3.
模拟酸雨对施肥条件下赤红壤氮磷淋失特征的影响 总被引：3，自引：0，他引：3
通过土柱模拟淋洗试验,研究了施用等量有机复合肥条件下,不同酸度模拟酸雨对赤红壤氮磷淋失特征的影响。结果表明,铵态氮、硝态氮、无机氮和总氮淋失量均随酸雨pH值增大而下降;pH 2.0模拟酸雨和对照(pH 6.5)的无机氮和总氮淋失量差异不显著,但均显著高于pH 3.0、pH 4.0和pH 5.0酸雨;pH 5.0模拟酸雨无机氮和总氮淋失量均最低,表明强酸性酸雨和中性淋洗液均促进氮淋失,而酸度与土壤接近的酸雨减少氮淋失。与对照相比,模拟酸雨对DP淋失无显著影响,但显著降低PP和TP淋失;不同模拟酸雨各形态磷淋失量均无显著差异,表明酸雨对赤红壤磷淋失影响有限。酸雨对淋滤液氮磷浓度动态变化和氮磷累计淋失量动态变化等均无显著影响。 相似文献
4.
通过土柱模拟淋洗试验,研究了施用等量有机复合肥条件下,不同酸度模拟酸雨对赤红壤氮磷淋失特征的影响。结果表明,铵态氮、硝态氮、无机氮和总氮淋失量均随酸雨pH值增大而下降;pH 2.0模拟酸雨和对照（pH 6.5）的无机氮和总氮淋失量差异不显著,但均显著高于pH 3.0、pH 4.0和pH 5.0酸雨;pH 5.0模拟酸雨无机氮和总氮淋失量均最低,表明强酸性酸雨和中性淋洗液均促进氮淋失,而酸度与土壤接近的酸雨减少氮淋失。与对照相比,模拟酸雨对DP淋失无显著影响,但显著降低PP和TP淋失;不同模拟酸雨各形态磷淋失量均无显著差异,表明酸雨对赤红壤磷淋失影响有限。酸雨对淋滤液氮磷浓度动态变化和氮磷累计淋失量动态变化等均无显著影响。 相似文献
5.
不同施肥处理对三峡库区柑橘园土壤氮磷淋失影响 总被引：1，自引：0，他引：1
在2017年8月利用原状土柱模拟淋溶试验对三峡库区秭归县柑橘园土壤的氮磷淋溶流失进行研究,探讨不同施肥处理对土壤氮、磷淋失的影响,为三峡库区农业面源污染的防控提供理论依据。试验设置6个处理,分别为不施肥处理(T0)、减量施肥(T1)、常量施肥(T2)、增量施肥(T3)、常量复合肥A施肥(T4)和常量复合肥B施肥(T5)。结果表明:(1)不同施肥处理下,柑橘园土壤淋滤液中总氮(TN)、总磷(TP)、硝态氮(NO_3~-—N)和铵态氮(NH_4~+—N)的淋溶浓度范围分别为37.16~163.07,0.61~6.69,27.54~79.38,2.37~7.10mg/L。(2)施肥量和施肥种类皆为土壤中氮磷淋溶的影响因素。在相同施肥种类下,土壤氮磷淋溶浓度随施肥量增加而显著增加,但施肥量高到一定程度后,淋溶浓度增长幅度会降低。在相同施氮量下,硝态氮的淋失受施肥种类影响最大,铵态氮最小。(3)在土壤淋滤液中,硝态氮为可溶性氮主要淋失形态,其淋失量占TN淋失量的比率为29.72%~46.18%,NH_4~+—N淋失量的比重为1.09%~2.05%。从研究结果推论,常量复合肥A施肥处理更有利于肥料氮向供植物吸收可溶性氮转化并降低施肥后土壤中氮素累积的风险。 相似文献
6.
控释复合肥配施保水剂的盆栽月季节水保肥效果 总被引：6，自引：3，他引：3
该文旨在探究肥料配施保水剂对土壤节水保肥能力的影响及其在盆栽月季中的实际应用效果,为其科学施用提供依据。采用土柱模拟和盆栽月季试验,研究普通复合肥与包膜型控释复合肥搭配0、0.25‰和0.5‰土壤质量的保水剂对土壤水、氮、钾淋失率及月季生长生理性状的影响。结果表明:土柱淋溶条件下,与普通复合肥配施等量保水剂处理相比,控释复合肥处理的氮、钾淋失率分别降低了72.4%~75.6%和81.5%~84.2%;普通复合肥两处理间的氮淋失量无差异,但随着保水剂用量的增加,钾淋失量显著减少11.6%~26.3%;月季盆栽试验中,与普通复合肥配施等量保水剂处理相比,控释复合肥配施保水剂的处理使月季初花期提前5~7 d,盛花期延长5~10 d,株高增加12.8%~36.0%,茎粗增加5.4%~15.2%,分别提高了月季叶片的超氧化物歧化酶SOD、过氧化氢酶POD活性12.6%~33.0%和14.5%~31.1%。控释复合肥配施0.25‰土壤质量保水剂能显著提高土壤节水、保肥能力和盆栽月季观赏价值,更能满足盆栽月季的生长及生理需求。 相似文献
7.
施氮模式对冬小麦/夏玉米产量及氮素利用的影响 总被引：7，自引：1，他引：6
采用大田试验,在小麦季N 250kg /hm2和玉米季N 200kg /hm2氮肥供应条件下,连续2年度（2007～2009）观测了不同施氮模式对冬小麦/夏玉米产量及氮素利用的影响。结果表明,与对照相比,常规施肥、有机无机复合肥、控释复合肥、控失复合肥以及改变氮肥基追配比处理均显著提高冬小麦/夏玉米子粒产量和干物质积累量,小麦季各处理产量大小依次为:控释复合肥控失复合肥有机无机复合肥改变氮肥基追配比常规施肥,提高幅度在107.5%～147.4%;玉米季各处理产量大小依次为:控释复合肥控失复合肥有机无机复合肥常规施肥改变氮肥基追配比,提高幅度在28.5%～56.1%。与常规施肥处理比较,控释复合肥、控失复合肥和有机无机复合肥处理冬小麦氮肥偏生产力和氮肥农学效率提高2.2～5.1 kg/kg,夏玉米提高3.6～7.6 kg/kg;但改变基追配比处理在小麦季高于常规处理,在玉米季则低于当地常规施肥处理。从产量和氮肥利用率方面综合分析,有机无机复合肥、控释复合肥、控失复合肥均可作为适宜研究区域推广的肥料品种,而改变基追配比处理相对较适宜冬小麦季。 相似文献
8.
控释肥对坡地农田地表径流氮磷流失的影响 总被引：7，自引：0，他引：7
2010年5-9月降雨季,在鲁中山区种植春花生的坡地农田中进行野外降雨径流观测试验,研究了不同坡度下,施用普通复合肥(CCF)和纯控释肥(CRF)对地表径流液和径流泥沙中铵态氮、硝态氮、可溶性磷、颗粒态氮和磷、总氮和总磷的影响。结果表明,花生生长前期,与CCF相比,施用CRF的坡地地表径流中可溶性养分流失含量较低,其中铵态氮含量低5.0%~74.2%,硝态氮含量低3.9%~37.0%,可溶性磷含量低7.1%~94.1%;CRF处理径流中颗粒态氮和磷含量在花生生长前期低于CCF处理,花生生长后期CRF处理径流液总氮、总磷含量高于CCF处理;在整个监测期内,CRF处理径流中总氮和总磷含量低于CCF处理。不同坡度下,随着坡度的增大,CCF和CRF的径流养分流失量变化为15°>10°>5°>0°,表明在坡地条件下,CRF能维持作物生长后期较高土壤养分含量,有利于提高氮磷的利用效率,减少雨季氮磷地表径流养分流失,降低农业面源污染。 相似文献
9.
通过田间径流微区定位试验,以中亚热带3种典型母质(花岗岩、红砂岩、红黏土)发育红壤花生坡地为研究对象,以当地常规化肥用量处理为对照,连续3年研究了在常规化肥用量减半条件下配施6个不同用量腐熟猪粪(猪粪含有0,0.5,1,2,4,8倍的对照处理磷用量)对红壤花生坡地水土流失和磷素流失的影响,以期为典型红壤地区合理施用猪粪提供科学依据。结果表明:化肥减半配施猪粪处理能有效降低红壤坡地的产流产沙,但随着猪粪用量的增加,径流水和泥沙磷含量均呈线性增加,环境风险增大。径流量和泥沙量均为花岗岩红壤红砂岩红壤红黏土红壤。配施3 500kg/(hm~2·a)猪粪,花岗岩红壤的径流量减少了28.0%、泥沙量减少了6.3%,红砂岩红壤的径流量减少了23.2%、泥沙量减少了37.1%;而配施7 000kg/(hm~2·a)猪粪,红黏土红壤的径流量减少了40.7%,泥沙量减少了12.8%。当花岗岩红壤、红砂岩红壤、红黏土红壤的猪粪用量分别达到14 000,28 000,28 000kg/(hm~2·a)时,径流水总磷平均含量超过地表水环境质量标准V类限值。径流水总磷含量为花岗岩红壤红黏土红壤红砂岩红壤,而泥沙总磷含量则为红黏土红壤花岗岩红壤红砂岩红壤。在减半化肥用量条件下花岗岩红壤和红砂岩红壤配施与常规化肥处理等磷量[P含量40kg/(hm~2·a)]的猪粪、红黏土红壤配施2倍常规化肥处理磷含量[P含量80kg/(hm~2·a)]的猪粪,可有效减少水土流失,且3年内不会增加磷素流失风险。 相似文献
10.
本文采用盆栽试验,在自然降雨条件下,监测了不同化肥用量与猪粪梯度用量配施条件下,两种不同肥力红黏土母质红壤在花生-萝卜轮作模式下的氮、磷渗漏淋失特征,土壤养分积累和作物产量变化,据此估算不同肥力红壤的猪粪安全消纳量。结果表明,养分渗漏淋失以NO_3~–-N为主,基本无磷素淋失风险。渗漏水中NO_3~–-N高峰值出现在播种施肥一个月以后,此时表现出随着猪粪用量增加而增加的趋势,其后NO_3~–-N浓度迅速下降且均低于地下水(III类)质量标准限值。在渗漏水NO_3~–-N高峰期,高肥力红壤渗漏水NO_3~–-N浓度一般都显著高于低肥力红壤,在配施化肥和高用量猪粪条件下,容易出现超标风险。猪粪施用容易引起土壤有效磷积累,且高肥力红壤的积累明显高于低肥力红壤,但无机氮积累不明显。随着猪粪用量的增加,低肥力红壤的花生产量一直呈增加的趋势,但高肥力红壤花生产量在猪粪用量达到一定水平后趋于稳定。综合考虑猪粪施用对地下水环境、土壤环境和作物产量的影响,得出在不配施化肥条件下,低肥力与高肥力红黏土红壤的猪粪磷安全消纳量分别为P 400、100 kg/(hm~2·a)(相当于含水量750 g/kg堆腐猪粪91.2、22.8 t/(hm~2·a));在常规化肥用量减半条件下,低肥力和高肥力红壤的猪粪磷安全消纳量分别为P 400、25 kg/(hm~2·a)(相当于含水量750 g/kg堆腐猪粪91.2、5.7 t/(hm~2·a))。在南方红壤地区,猪粪应多施用于低肥力红黏土红壤。 相似文献
11.
B. Ulén 《Soil Use and Management》1999,15(1):56-61
Abstract. A long-term lysimeter experiment with undisturbed monoliths studied leaching behaviour and balances of phosphorus (P), potassium (K) and nitrogen (N) during a seven year crop rotation on four types of soil receiving inorganic fertilizers, manure and grass compost respectively. It was shown that application of manure did not lead to any direct change in nutrient leaching, unlike the application of fertilizers to soils of normal fertility. However, soil type considerably affected the nutrient concentrations in the drainage water.
Manure applied in amounts equal to the maximum animal density allowed by Swedish legislation slightly oversupplied P and N (0.5–3.5 and 18–38 kg ha−1 y−1 respectively) compared to the crop requirement and leaching losses for most of the soils. The relationship between lactate-soluble P in the topsoil and the concentrations of dissolved P in the drainage water was very strong. However the strength of this relationship was dependent on just one or two soils. P losses from a fertile sandy soil were large (1–11 kg ha−1 y−1 ) throughout the crop rotation and average crop removal (13 kg ha−1 y−1 ) plus the leaching losses were not balanced (average deficit 3–6 kg ha−1 y−1 ) by the addition of fertilizer, manure or grass compost. No decreasing trend was found in the P losses during seven years. However, the K deficit (average 26 kg ha−1 y−1 ) led to a significant reduction in the leaching trend from this soil. The other soils that had a smaller K deficit showed no significant reduction in the leaching of K. 相似文献
Manure applied in amounts equal to the maximum animal density allowed by Swedish legislation slightly oversupplied P and N (0.5–3.5 and 18–38 kg ha
12.
不同有机物及其堆肥与化肥配施对小麦生长及氮素吸收的影响 总被引：10，自引：5，他引：5
采用15N示踪技术,选用水稻土和灰潮土在宜兴进行小麦盆栽试验,研究了稻草、猪粪及其堆肥与化肥配施对作物生长及氮素吸收的影响。结果表明,在水稻土和灰潮土上,不同有机物及其堆肥与化肥配施分别比单施化肥增产4.46%～24.82%和1.01%～20.53%,稻草堆肥和猪粪堆肥配施化肥处理籽粒产量分别高于稻草和猪粪直接与化肥配施处理。稻草和猪粪堆肥后更利于作物吸收氮素,增加植物体内15N累积。两种土壤上15N回收率表现为相同配比的堆肥处理未堆肥处理单施化肥处理。随着小麦生育期的推进,土壤微生物量氮和矿质态氮含量均呈下降趋势,稻草和猪粪处理的微生量氮含量始终高于稻草堆肥和猪粪堆肥处理。有机无机肥配施处理土壤矿质态氮在小麦生育前期低于单施化肥,成熟期则高于单施化肥。整个生育期中,稻草堆肥和猪粪堆肥处理土壤矿质态氮含量分别高于稻草和猪粪处理。因此,有机物堆肥后与化肥配施更有利于提高产量,促进作物对氮素的吸收利用。 相似文献
13.
红壤的供氮能力及化肥氮的去向 总被引：14，自引：1，他引：14
采用盆栽试验 ,研究了由第四纪红色黏土和红砂岩发育的不同侵蚀程度红壤以及施用有机或无机肥 1 0年以上培肥的红壤在不加外源氮肥条件下的自然供氮能力 ,以及施用1 5N肥源后肥料氮在土壤 -作物系统中的去向。结果表明 :红砂岩发育红壤 (红砂土 )的矿化量和供氮量显著高于第四纪红黏土 (红黏土 ) ,同一母质中轻度侵蚀红壤的矿化量和供氮量又显著高于重度侵蚀红壤。培肥后红壤的矿化量和供氮量显著提高 ,其中有机培肥红壤高于无机培肥红壤。侵蚀红壤的氮肥利用率低 ,土壤残留氮率较高 ,氮肥损失率不大 ,其中红砂土的氮肥残留率明显低于红黏土 ,而氮肥损失率却显著高于红黏土。培肥后红壤的氮肥利用率明显增加 ,其中有机培肥红壤的氮肥利用率和残留率显著高于无机培肥的红壤 ,而氮肥损失率却明显低于无机培肥红壤。 相似文献
14.
土壤中可溶性氮和pH对有机肥和化肥的短期响应 总被引：3，自引：0，他引：3
通过温室盆栽试验,施用猪粪堆肥(PC)、污泥堆肥(SC)、菜籽饼肥(CM)和无机化肥(IF)后,对土壤pH值和不同形态氮素的短期响应进行研究,探讨土壤可溶性无机氮、有机氮及土壤pH值之间的相互关系。结果表明,CM,PC和IF处理的pH值都呈现先快速下降后缓慢回升的趋势,但PC处理下降幅度较小;而SC处理和不施肥对照(CK)处理的pH值基本不变;不同施肥处理均提高了土壤中氮素水平,3种有机肥中以CM处理最显著地提高了土壤中总可溶性氮(TDN)、NH4+-N、NO3--N和可溶性有机氮(DON)浓度,PC处理的次之,SC处理的最弱,而IF处理与CM处理提高幅度相似。不同施肥处理中土壤可溶性氮表现出不同的短期响应,IF处理和CM处理的TDN分别经过11,13d的稳定期后迅速上升到一个较高的水平,至31d开始下降;PC处理和SC处理未出现突然升高的现象,而是前20d较稳定在一定的范围内波动,之后缓慢下降,总体与对照趋势一致。不同处理土壤中NH4+-N均呈下降趋势;IF处理、CM处理的NO3--N呈增加趋势,PC处理的呈先增加后降低趋势,而SC处理的呈缓慢下降趋势,结果说明不同有机肥在土壤中的转化存在明显的差异。相关性分析显示,CM处理、IF处理的土壤pH值与NH4+-N呈极显著正相关,而与NO3--N呈极显著负相关;除PC处理外,其他处理的DON含量与TDN具有显著正相关性,而PC处理的DON同时与NH4+-N、NO3--N呈显著负相关。 相似文献
15.
中国洞庭湖区稻田土壤氮素淋溶损失的系统研究 总被引：5，自引：0，他引：5
A two-year lysimeter study was conducted to study the effects of different fertilizers and soils on nitrogen leaching loss in a double rice cropping system by considering three major types of paddy soils from the Dongting Lake area. The results showed that N concentration in the leachate did not differ significantly among the treatments of urea, controlled release N fertilizer and pig manure and that all these fertilizers produced higher total nitrogen (TN) concentrations in the leachate compared to the case where no fertilizer was applied. The TN leaching loss following urea treatment accounted for 2.28%, 0.66%, and 1.50% of the amount of N applied in the alluvial sandy loamy paddy soil (ASL), purple calcareous clayey paddy soil (PCC), and reddish-yellow loamy paddy soil (RYL), respectively. Higher TN loss was found to be correlated with the increased leachate volume in ASL compared with RYL, and the lowest TN loss was observed in the PCC, in which the lowest leachate volume and TN concentration were observed. Organic N and NH4+ -N were the major forms of N depleted through leachate, accounting for 56.8% and 39.7% of TN losses, respectively. Accordingly, soil-specific fertilization regimens are recommended; in particular, the maximum amount of fertilizer should be optimized for sandy soils with a high infiltration rate. To avoid a high N leaching loss from rice fields, organic N fertilizers such as urea or coated urea should primarily be used for surface topdressing or shallow-layer application and not for deep-layer application. 相似文献
16.
不同有机肥对花生营养吸收、土壤酶活性及速效养分的影响 总被引：10，自引：1，他引：9
通过盆栽试验,研究等养分投入条件下,施用化肥与不同有机肥(猪粪、牛粪、鸡粪、麸酸有机无机复混肥)对花生营养吸收、土壤酶活性及速效养分的影响。结果表明,与化肥相比,施用有机肥脲酶活性提高6.2%～22.1%,磷酸酶活性提高7.9%～27.9%,过氧化氢酶活性提高45.1%～65.2%,分别以猪粪、鸡粪、麸酸有机无机复混肥最高,而转化酶活性各处理表现不一。施用有机肥较化肥促进了N、P、K养分向花生果仁转移累积,果仁吸N量、吸P量、吸K量、吸S量分别较化肥提高22.7%～78.0%、47.1%～74.5%、65.2%～91.6%、5.6%～61.2%,其NPK养分总吸收量以麸酸有机无机复混肥最高。施肥均提高了种植花生后的土壤N、P、K速效养分含量,施用麸酸有机无机复混肥还明显改善了土壤S素营养。 相似文献
17.
不同肥料结构对红壤稻田氮素迁移的影响 总被引：14，自引：3，他引：14
不同肥料结构对红壤稻田淹水层、不同深度渗漏水、外排水和土壤剖面中氮素的含量、形态及其动态变化的影响研究结果表明 ,各处理淹水层、外排水和渗漏水中NH4+-N含量明显高于NO3--N。淹水层中N的含量 ,水稻生育前期以单施化肥的高 ,约相当于配施有机肥的 1.18～ 1.20倍 ,而水稻生育后期 ,后者为前者的 1.11～ 1.2 1倍。各处理外排水中N素的输出量均以苗期最高 ,单施化肥明显大于配施有机肥。土壤剖面中NH4+-N向下迁移比碱解N更为明显 ,且配施有机肥的远高于单施化肥的 ,而NO3--N则相反。不同深度渗漏水中NO3--N的比例 ,上层 (30cm)低于下层 (50cm) ,随水逸出的N量各处理渗漏水均小于外排水 ;随水输入的N量远低于随水输出的N量 ,且以单施化肥的N亏损最大。水稻未利用的N量也以单施化肥的最大 ,约为配施有机肥的 1.0 9倍。 相似文献
18.
Cheng-Long Wu Qi-Rong Shen Jing-Dong Mao Yang-Chun Xu 《Biology and Fertility of Soils》2010,46(2):127-137
The present study was carried out on pot experiments with rice (Oryza sativa L. cv. Wuyujing 7) and winter wheat (Triticum aestivum L. cv. Yangmai 6) rotation in a sandy and a clayey soil fertilized with 15N-labeled ammonium sulfate (AS) and 15N-labeled rabbit feces so as to study the mechanisms of reduction of fertilizer N loss by organic fertilizers. The treatments
included: (1) control without any N fertilizer application; (2) fertilization with 15N-labeled AS (IF); (3) fertilization with labeled rabbit feces (OF); (4) fertilization with either 40% 15N-labeled rabbit feces and 60% unlabeled AS (IOF1) or (5) 40% unlabeled rabbit feces and 60% 15N-labeled AS (IOF2). In the rice season, the IOF treatments compared to the IF treatment decreased the percentage of lost
fertilizer N from the sandy and clayey soils, whereas it increased the percentage of fertilizer N, present as mineral N and
microbial biomass N (MBN). During the second season, when soils were cropped to winter wheat, the IOF treatments in comparison
with the IF or OF treatment increased mineral N and MBN contents of soils sampled at tillering, jointing, and heading stages,
and such increases were derived from the organic N fertilizer in the sandy soil and from the inorganic N fertilizer in the
clayey soil. The increased MBN in the IOF treatments was derived from inorganic fertilizers applied both soils. Therefore,
in the IOF treatment, during the rice season, the organic N increased the immobilization of inorganic N in MBN, while the
inorganic N fertilizer applied to both soils stimulated the uptake of organic N and the organic N fertilizer increased the
uptake of inorganic N by winter wheat; the inorganic N increased the recovery of organic N in the plant-soil system after
harvesting the winter wheat. 相似文献
19.
A. Bu&#;ien&#; A. &#;lepetien&#; D. &#;imanskait&#; A. Svirskien&#; B. Butkut&#; 《Soil Use and Management》2003,19(4):291-297
Abstract. To determine the effects of low-input agriculture on soil properties, we compared several forms of arable land management in a rotation experiment lasting 8 years on a Cambisol in Lithuania. Conventional arable cropping with applications of inorganic fertilizers increased the potassium (K) status of the soil, but resulted in losses of nitrogen (N) from the soil by mineralization and leaching. With ley–arable integrated cropping, a similar fertilizer regime based on farmyard manure (FYM) augmented with inorganic fertilizers increased the phosphorus (P), K, organic matter and N in the soil, as well as increasing N loss by leaching. These two high-input regimes were compared to three systems with less or no input. A reference treatment with no input, which produced small crop yields, maintained its nutrient status and organic matter. An organic regime receiving FYM and green manure lost only P, but maintained its K and N status, while a second organic regime in which the FYM was replaced by composted sewage maintained its fertility. The microbial activity varied somewhat from treatment to treatment, with the largest numbers of almost all groups of microorganisms in the reference treatment. All treatments led to decreases in fulvic acid, and the soil managed conventionally lost humic acid, too. The content of humic acid increased in the treatments where FYM was applied and in the reference soil, and the fraction bound to calcium increased in the integrated and the first organic treatments. The soil structures under the integrated cropping and second organic regime were the most stable. Of the low-input systems, the second organic regime seemed the most sustainable. 相似文献