撒施液体复合肥后不同蓄水深度的水分管理对稻田养分流失潜力的影响

为探究施用液体复合肥水分管理对春耕稻田养分流失潜力的影响,采用滞水时间控制与单排单灌水分管理系统相结合的关键技术,对3(H_3)、6(H_6)和9 cm(H_9)3个蓄水深度处理小区田面水中氮、磷养分流失潜力进行了研究。结果表明:(1)H_3的NO_3~--N的相对流失量在第1 d后呈整体上升趋势,于第5 d达2.5 mg,而H_9和H_6则呈下降趋势;H_6于第3 d后呈反弹上升趋势,但3个蓄水处理NO_3~--N的流失潜力处于较低的水平。(2)H_6、H_3和H_9在第1 d,NH_4~+-N的相对流失量分别达151.26、90.75和48.24 mg,处于较高水平,之后则呈下降趋势,于第5 d达较低水平,但总体上呈H_6H_9H_3的态势。(3)H_6和H_9于第1~3 d,总磷相对流失量分别达105.88和118.29 mg,处于较高水平,第3 d后呈下降趋势,但幅度不大;H_3呈缓慢上升趋势,于第1 d和第3 d达峰值,分别为50.11和50.57 mg,之后则缓慢下降至第5 d的较低水平。(4)H_6、H_9和H_3田面水总氮的相对流失量,于第1 d达峰值,分别为521.64、372.06、293.12 mg,之后迅速下降至第3 d的较低水平,但总体上呈H_6H_9H_3。施用液体复合肥后,由于硝化作用不强,NO_3~--N的流失潜力不大;将H_3和H_9处理滞水至第5~7 d后排水,可有效减少NH_4~+-N的排放;将H_3处理滞水至第5 d后排水,可有效减少总磷的排放;将H_3和H_9处理,滞水至第5 d或第7 d排水,可有效减少总氮的排放。因此,就春耕稻田撒施液体复合肥而言,选择蓄水3 cm,并滞水至第5 d后排水,为一种清洁的水分管理模式。     

应用分形理论估算丹江口水库水源区总氮、总磷的流失量

[目的]掌握区域农业面源污染物的流失状况,证明分形计算结果的可靠性。[方法]采用分形理论对丹江口水库水源区河南省所在的区域2013年总氮(TN),总磷(TP)的流失量进行估算,并与输出系数法的值进行比较。[结果]研究区污染物的流失以氮为主,TN的流失量是TP的7.16倍;禽畜养殖引起的流失量最多,占了总量的69.93%,农田化肥中的流失量占21.99%;灌河产生的污染物最多,其次是丹江、淇河、滔河,但在流失强度上却是滔河最大,其次是灌河、丹江、淇河;通过配对t检验分析将分形方法计算的污染物总量与输出系数法相比,在0.1水平下有统计学意义,说明前者较后者更能反映实际。[结论]用分形方法估算区域污染物的面源污染是可行的,应当加强区域禽畜粪尿和农田化肥的管理,以确保丹江口水库水质。     

丹江口库区土壤氮磷养分流失特征

[目的]研究丹江口库区土壤的水土流失和非点源污染物氮磷流失的特点,为农业非点源污染模型的建立提供理论依据。[方法]通过室内人工模拟降雨试验,研究了坡度和施肥等处理对产流产沙、氮磷养分(硝态氮、铵态氮、总氮、有效磷和总磷)流失特点的影响。[结果](1)随着坡度的增加,平均入渗率和初始产流时间呈减小趋势,而径流总量和泥沙总量呈增加趋势。(2)相同施肥处理下,随着坡度的增加,泥沙中硝态氮、总氮、有效磷和总磷的流失浓度呈减小趋势,铵态氮流失浓度在不施氮肥条件下呈减小趋势,而在施氮肥处理下呈增加趋势。(3)在相同坡度条件下,随降雨时间推移,总氮浓度呈先减小后趋于稳定的趋势;铵态氮浓度随施肥处理的变化均呈现出波浪形变化;在施氮肥时,径流中硝态氮的浓度随着时间的推移,呈逐渐减小并趋于平缓的趋势,而在不施氮肥时几乎无变化。[结论]在不同施肥措施和坡度条件下,硝态氮主要随径流而流失,为随泥沙流失的8~11倍;铵态氮主要是随径流泥沙而流失,为随径流流失的1~17倍;总氮则是随径流和径流泥沙共同流失;有效磷和总磷都是以泥沙结合态流失为主,分别为随径流流失的1 000~6 200和1~3倍。     

Yield responses of cauliflower (Brassica oleracea L. var. Botrytis) to different water and nitrogen levels in a Mediterranean coastal area

Abstract

Global warming along with the increasing population and fresh water shortages necessitates a specific fertilization programme under water-scarce conditions. This study was conducted to investigate the effects of different irrigation and nitrogen levels on yield, growth components and water use characteristics of cauliflower (Brassica oleracea L. var. Botrytis cv. Tetris-F1) cultivated in a field for three consecutive years from 2005 to 2007 in the Eastern Mediterranean region of Turkey. Four irrigation (Kcp) levels with a drip irrigation system based on adjustment coefficients (0, 0.75, 1.0 and 1.25) of pan evaporation were used. Nitrogen (N) treatments were consisted of four different nitrogen rates (0, 75, 150 and 225 kg N ha^–1). The following yield and quality parameters were determined: curd weight, curd diameters, number of leaves per crop, above ground biomass (AGB) and curd/AGB ratio. Fertilizer use efficiency (FUE) and leaf mineral contents were also determined to clarify the productivity of N treatments. According to the results; the amount of irrigation water and/or total received water affects the plant water consumption, consequently, crop yield in a field grown cauliflower. The highest yield was obtained in Kcp1.0 irrigation level which represents full irrigation treatment. The excess water applications had negative effect on yield and AGB of cauliflower. Highest yield was obtained at 225 kg N ha^–1.

The water use efficiency and irrigation water use efficiency values increased with decreasing irrigation rate. However, lower Kcp coefficients resulted in lower total yield. The FUE in irrigation treatments showed linear increases from non irrigation to full irrigation plots. However, excessive irrigation caused a decrease in FUE. It can be recommended that the Kcp1.0 crop-pan coefficient with 225 kg ha^–1 nitrogen application can be used to achieve the highest yield for field grown cauliflower in the Eastern Mediterranean coastal region of Turkey.     

丹江口水库农业径流小区土壤氮磷流失特征

通过对丹江口水库小流域雨季(2013年8月)观测的降雨—径流农业小区试验数据,分析不同种植作物下农田地表产流规律,研究土壤氮磷流失特征,为库区农业面源污染控制提供依据。结果表明,农业小区径流总磷(TP)含量在0.13~0.82mg/L之间,颗粒态磷(PP)占TP比例超过60%,径流中TSS与PP也呈现极显著相关(p0.01),表明磷素流失主要以颗粒态流失为主。径流总氮(TN)含量范围为0.7~4.7mg/L之间,TN流失量与硝态氮极显著相关(p0.01),径流中硝态氮占TN比例也超过了50%,表明硝态氮是地表径流无机氮流失的主要成分。25°玉米、15°荒地径流小区的氮流失率超过了1.5%、磷流失率超过了0.12%,高于其它类型的小区,可能与这2种小区高坡度、低植被覆盖度有关。土壤氮的流失风险要高于磷,是面源污染的主要控制目标。利用梯田种植作物,同时在坡地上形成相对较高的植被覆盖密度是减少这一地区土壤养分流失有效手段。     

传统和优化水氮管理对蔬菜地土壤氮素损失与利用效率的影响

通过3年田间定位试验利用氮素平衡方程模拟了传统水氮管理和优化水氮管理下连作蔬菜地土壤无机态氮含量的变化,分析了两种水氮管理对土壤氮素损失量及氮素利用效率的影响。结果表明：优化水氮管理下花椰菜、苋菜和菠菜生长期内土壤平均(2年或3年)氮素损失量(氨挥发、反硝化和硝态氮淋洗的总和)只有传统水氮管理下花椰菜、苋菜和菠菜生长期内土壤平均氮素损失量的9%、8%和18%;氮素利用效率是传统水氮管理下各蔬菜氮素利用效率的2.3倍、3.2倍、1.7倍,而两处理间蔬菜平均产量并无显著差异。     

Drip fertigation and irrigation interval effects on growth,productivity, nutrient,and water economy in summer peanut

ABSTRACT

The present investigation was carried out to study the effect of irrigation intervals and fertigation on growth, yield, and quality of peanut as well as an account of fertilizer and water savings under drip irrigation combined with fertigation. Pod and haulm yields and economics of peanut with application of irrigation water at I_1, i.e. 4 day interval through drip (10 day in surface irrigation) did not differ significantly compared with I_2, i.e. 6 day interval through drip (15 day in surface irrigation). However, significantly higher kernel and oil yields were obtained at I₁ and also recorded higher partial factor productivity (PFP). Our study showed that drip irrigation saved 37.2% irrigation water over surface method. Fertigation at 75% Nitrogen & potassium (NK) through drip with 75% P in soil (F₃) significantly improved pod, haulm, kernel, and oil yields by 14.3%, 11.5%, 13.9%, and 12.3%, respectively, while net returns increased by INR 13,499 ha^?1 over 50% NK through drip with 50% P in soil (F₂) and at par with others. Fertigation at 50–100% NK with 50?100% P in soil (F₂ to F₄) could save 36.4–37.3% irrigation water over F₁. Maximum PFP was recorded under F₂.

Abbreviations: N: Nitrogen; P: phosphorus; K: potassium; M: million     

水氮管理对黑土稻作土壤碳氮磷化学计量特征的影响

为阐明不同水氮管理模式对黑土稻作产量和土壤碳氮磷化学计量特征的影响。设置3种灌溉模式（常规淹灌、浅湿灌溉、控制灌溉）和4种氮肥梯度（0、85、110、135 kg/hm2）,探究水稻产量、土壤碳氮磷含量、化学计量比及层化率对不同水氮管理模式的响应规律。结果表明：控制灌溉模式下,水稻通过形成足量大穗提高库容,小幅增加结实率,从而显著提高产量（p<0.05）。稻田土壤有机碳（SOC）、土壤总氮（STN）、土壤总磷 (STP) 含量随土层深度增加而降低,施氮处理可显著提升SOC、STN含量并降低STP含量（p<0.05）。常规淹灌模式增加SOC、STN含量,控制灌溉模式增加STP含量。土壤C/N随施氮量增加而降低,土壤C/P、N/P随施氮量增加而升高,施氮能提升不同土层平均C/N层化率,降低C/P、N/P层化率。相比常规淹灌,控制灌溉模式能提升不同土层SOC、STP含量层化率,在一定程度上说明控制灌溉配施适宜氮肥可以改善土壤质量,综合考虑CN2为最优水氮管理方式。     

南方丘陵地区生物黑炭和有机肥配施化肥的应用研究

研究生物黑炭和有机肥配施化肥对旱地作物种植和养分损失的影响,旨在进一步探索高温多雨的南方丘陵地区旱地作物合理施肥和高产高效种植以及资源优化利用的有效途径。采用田间小区试验,设置了5个处理:不施肥(CK)、单施化肥(CF)、化肥+生物黑炭(CF+B)、有机无机肥配施(OF+CF)和有机无机肥配施且添加生物黑炭(OF+CF+B),探讨了生物黑炭和有机肥施用对春玉米产量、地表氮磷径流损失、作物氮磷肥料利用率的影响。结果表明:生物黑炭或有机肥的施用可显著增产8.2%~11.1%,但有机肥和生物黑炭结合施用增产效果最佳,增产率可高达13.7%。相比CF处理,CF+B处理可显著降低15.9%的氮素径流损失和24.2%磷素径流损失,显著提高26.3%和11.8%的地上部氮磷累积量;OF+CF处理可显著降低17.5%的氮素径流损失和25.0%磷素径流损失,提高36.5%(P0.05)和8.2%(P0.05)地上部氮磷累积量;OF+CF+B处理可显著降低33.3%的氮素径流损失和35.2%磷素径流损失,显著提高52.1%和29.0%地上部氮磷累积量,且氮磷肥料利用率最高,分别达49.1%和26.4%。OF+CF+B处理施肥方式一方面可促进春玉米旺盛生长,增加地表植被覆盖度和增强土壤的抗蚀性,显著降低了地表的径流体积;另一方面可以全面降低土壤氮磷养分溶解态和颗粒态的径流损失,培肥了地力。因此,从产量经济效益和环境效益方面综合来看,认为添加生物黑炭和有机肥部分替代化肥结合化肥施入土壤是最合理的施肥方式,值得在该区域进行推广和应用。     

水肥管理及生物炭施用对作物产量和磷效率及磷淋失的影响

为探讨中国北方褐土区典型种植模式——冬小麦-夏玉米体系水分优化、养分优化以及生物炭施用对作物产量、磷效率和磷素淋失的影响,2016—2019年于陕西杨凌土(黄土母质,自然褐土发育)区进行田间渗漏池试验,设计习惯水肥(CP1、CP2, CP1处理渗漏池深为120～150 cm, CP2处理渗漏池深为100 cm)、灌水优化(CP1-W)、养分优化(CP1-F)、水分养分优化(OPT)、习惯水肥+生物炭(CP2+B)以及水分养分优化+生物炭(OPT+B)7个处理,研究作物产量、磷肥偏生产力和磷素淋失的响应。结果表明,CP1-W、CP1-F和OPT处理3年平均冬小麦、夏玉米及作物总产量均与CP1处理无显著差异。CP1-F和OPT处理较CP1处理均显著增加磷肥偏生产力,平均增幅分别为69.3%和56.4%。与CP1处理相比, CP1-W和CP1-F均没有显著影响各形态磷的淋失量,而OPT处理的颗粒磷淋失量显著减少58.4%。施用生物炭对3年平均作物总产量无显著影响,而在CP2+B处理磷肥偏生产力显著提高43.6%;在OPT+B处理磷肥偏生产力无显著变化。CP2+B处理各形态磷素的淋失量均与CP2处理相似, OPT+B处理第1年可溶性有机磷、颗粒磷和总磷淋失量较OPT处理分别显著降低60.0%、57.1%和62.4%,但后两年OPT+B处理总磷淋失量却显著增加。综合3年的结果发现,在不同条件下施用生物炭对各形态磷素淋失均无显著影响。上述结果表明,褐土区在农户水肥的基础上合理降低水肥用量,可以提高磷肥利用率,降低磷素淋失量,保障作物产量;而施用冬小麦秸秆生物炭对作物产量、磷素淋失无显著影响,对磷肥偏生产力的影响结果不一致,有待进一步研究。     

灌溉模式和供氮水平对水稻氮素利用效率的影响

以Ⅱ优838为材料,湖北潮土为供试土壤,通过2年稻麦轮作柱栽试验研究了2种灌溉模式（FW: 土表淹水3 cm; CW: 保持土壤湿润但土表不积水）和4个供氮水平(N 0、126.0、157.5、 210.0 kg/hm2）对水稻地上部干物重、 氮素积累量、 氮素利用效率的影响。结果表明,灌溉模式和供氮水平对水稻产量、 地上部氮素积累量和氮素利用效率均有显著（P0.05）或极显著影响（P0.01）。其中,淹水处理下水稻产量、 地上部氮素积累量、 水稻氮素农学利用率、 氮肥吸收利用率、 氮肥偏生产力和氮素生理利用率显著高于控水处理;地上部生物量及氮素积累量随供氮水平的提高而增加趋势明显; 氮肥农学利用率、 氮肥偏生产力和氮素生理学利用率均表现为随施氮量提高而下降的趋势,但减氮25%处理（N 157.5 kg/hm2）与常规施氮量处理（N 210.0 kg/hm2）间的差异并不显著。综合分析水稻产量与氮素吸收利用效率的各项指标,在8个供试处理中,淹水灌溉模式并减氮25%的处理为值得推荐的稳产高效水氮运筹模式。     

不同滴灌施肥模式对棉花产量及养分吸收的影响

通过等养分和等成本施肥田间试验,研究不同滴灌施肥模式对棉花产量及养分吸收的影响。试验设4种滴灌施肥模式,分别为常规基施(CK)、常规追施(DCK)、普通滴灌专用肥(F1)和高磷钾滴灌专用肥(F2)。结果表明,在等养分施用条件下,高磷钾滴灌专用肥和普通滴灌专用肥处理的棉花干物质重、养分吸收量和产量均显著高于常规基施处理,但普通滴灌专用肥和常规追施处理差异不大;常规基施处理的氮肥和磷肥的利用率最低,普通滴灌专用肥和常规追施处理的氮肥和磷肥利用率差异不显著,高磷钾滴灌专用肥可显著提高磷肥利用率。在等成本施用条件下,常规追施处理的棉花干物质重、养分吸收量和产量最高,而高磷钾滴灌专用肥、普通滴灌专用肥和常规基施处理无显著差异。因此,滴灌专用肥尤其是高磷钾滴灌专用肥具有较好的应用效果,但是如何降低肥料成本是滴灌专用肥技术面临的重要问题。     

三峡库区坡耕地磷素流失特征分析

Eutrophication in the Three Gorges Reservoir has become a serious issue, and phosphorus (P) is the nutrient thought to be primarily responsible although there are few studies about P loss from the mostly sloping farmlands of the area. This work investigated the amounts and forms of P loss from 9 farmlands with the slopes of 4°, 9°, and 17° in a small watershed, Wangjiagou in Fuling District, Chongqing of China. The slope of the relationship between runoff and rainfall increased with field slope; i.e., there was a significant interaction between the effects of rainfall and field slope on water export. For sediment export by surface runoff, there was no interaction between field slope and rainfall, and the intercept of the relationship between rainfall and sediment loss was significantly different for the 3 slopes. The main P loss was from sediments, regardless of slope. In the runoff water, particulate P was the largest P fraction, and its loss was greatest from the steepest land and least from the flattest. The release of total P and available P from sediments followed the same trend. The P loss during May to July in Wangjiagou was more than 60% of the annual total.     

中国滇池流域土地利用方式对土壤侵蚀和养分状况的影响

Soil erosion and loss of soil nutrients have been a crucial environment threat in Southwest China. The land use and its impact on soil qualities continue to be highlighted. The present study was conducted to compare soil erosion under four land use types(i.e.,forestland, abandoned farmland, tillage, and grassland) and their effects on soil organic carbon(SOC), total nitrogen(TN) and total phosphorus(TP) in the Shuanglong catchment of the Dianchi Lake watershed, China. There were large variations in the erosion rate and the nutrient distributions across the four land use types. The erosion rates estimated by137 Cs averaged 2 133 t km-2year-1under tillage and abandoned farmland over the erosion rate of non-cultivated sites, and the grasslands showed a net deposition. For all sites, the nutrient contents basically decreased with the soil depth. Compared with tillage and abandoned farmland, grassland had the highest SOC and TN contents within 0–40 cm soil layer, followed by forestland. The significant correlations between137 Cs, SOC and TN were observed. The nutrient loss caused by erosion in tillage was the highest. These results suggested that grassland and forestland would be beneficial for SOC and TN sequestration over a long-term period because of their ability to reduce the loss of nutrients by soil erosion. Our study demonstrated that reduction of nutrient loss in the red soil area could be made through well-managed vegetation restoration measures.     

节水控肥下有机无机肥配施对日光温室黄瓜–番茄轮作体系土壤氮素供应及迁移的影响

本试验以日光温室秋冬茬番茄-冬春茬黄瓜轮作体系为研究对象,采用田间小区试验,研究了5季节水控肥（冬春茬黄瓜和秋冬茬番茄季N-P2O5-K2O总投入量分别为600-300-525 kg/hm2和450-225-600 kg/hm2）有机无机肥配施对 040 cm（根区）土壤硝态氮供应、 40100 cm（根区以外）硝态氮残留和 0100 cm土体不同形态氮素淋失的影响,探索了设施蔬菜生产中节水节肥潜力,为构建设施蔬菜合理水肥管理下土壤肥力培育和土壤质量提升模式提供技术支持。试验结果表明, 1）农民习惯水肥管理节水节肥潜力较大; 节水控肥后0100 cm土体硝态氮积累量、 矿质氮和有机氮渗漏量均明显下降,种植蔬菜经济效益显著增加。2）商品有机肥猪粪与化肥在土壤无机氮供应方面的效果接近; 节水控肥1/41/2 猪粪氮替代1/41/2 化肥氮后,040 cm土体硝态氮供应和40100 cm土体硝态氮残留均无显著变化,但是随着猪粪氮配施比例的增加,土壤溶液渗漏量及养分淋失量呈增加趋势。3）施用秸秆促进了土壤无机氮固持,降低根区土壤硝态氮供应水平,提高土壤养分保蓄能力; 节水控肥1/2秸秆氮替代1/2化肥氮后,040 cm土壤硝态氮供应量平均下降34.3%~56.2%,40100 cm土体硝态氮残留量下降42.5%~87.8%, 0100 cm土体土壤溶液渗漏量下降65.0%,硝态氮淋失量下降 82.0%,而产量和经济收入无显著差异。根据本试验结果,对于新建温室可采用单施化肥、 化肥与猪粪配施方案,能在短时间内提高土壤无机氮供应强度,满足蔬菜氮素需求; 对于种植了一段时间的温室,可采用冬春茬黄瓜季化肥配施猪粪秋冬茬番茄季化肥配施秸秆方案,能固定积累于土壤中的无机氮,提高土壤养分容量,保证根层土壤氮素的稳定供应,降低环境风险,维护设施农业的可持续发展。     

太湖地区稻田田面水氮磷动态特征及径流流失研究

为探讨稻田氮磷养分地表径流流失特征,以太湖地区典型稻田为研究对象,通过在溧阳、宜兴两地实施田间试验,对稻田施肥后田面水氮磷动态变化特征及径流流失进行了研究。结果表明：两试验点田面水总氮浓度均在施肥当日达到最高,然后迅速下降,基肥在施肥7 d后逐渐趋于稳定,而追肥则在施肥5 d后逐渐趋于稳定;田面水总磷浓度也是在施肥后的当日达到最高,而后迅速下降,8 d后基本趋于稳定;施肥后田面水总氮及总磷浓度与施肥天数均可用指数方程进行拟合,且均达极显著水平;溧阳和宜兴两试验点稻季总氮径流量分别为8.21,10.73 kg/hm^2,分别占稻季氮肥总投入量的2.49%和3.25%,总磷径流量分别为0.58,0.75 kg/hm^2,分别占稻季磷肥总投入量的0.97%和1.25%。     

碎石含量对三峡库区坡耕地土壤氮磷流失特征的影响

坡耕地是三峡库区水土流失的主要来源,导致土壤养分的损失,严重影响库区生态环境建设与社会经济可持续发展。库区坡耕地土壤浅薄化和砾质化特征明显,但目前对含碎石坡耕地土壤侵蚀和养分流失特征的研究尚不多见。该研究通过设置3个降雨梯度（60、90、120 mm/h）和4种碎石含量（0、10%、20%、30%）,开展人工模拟降雨试验,分析各试验条件下含碎石土壤产流产沙和氮磷流失特征。结果表明：1）碎石主要通过改变土壤结构以增大产流产沙量来促进氮磷流失,而对相应流失速率与流失浓度的变化规律影响较小,不同碎石含量下泥沙产量的变异系数更高,且泥沙中不同碎石含量下的氮磷流失量显著性差异更强（P<0.05）;2）泥沙中累计磷流失量略微大于氮流失量,有效磷几乎不随泥沙流失,有效氮约占全氮流失量的15%;径流中氮素流失量几乎为磷素的10倍且以有效氮为主,占总氮流失量的75%,有效磷占总磷流失量的25%;3）不同碎石含量下有效氮流失规律大致相同,径流中硝态氮约占有效氮流失量的70%,而泥沙中则以铵态氮为主,约占65%;4）不同碎石含量下土壤中氮磷元素均以随侵蚀产沙流失为主,累计产沙量与氮磷元素随侵蚀产沙流失...     

不同施肥对雷竹林渗漏水中可溶性有机碳、氮流失的影响

【目的】雷竹(Phyllostachys praecox f. preveynalis)是一种在我国亚热带地区被广泛引种栽培的优良笋用竹。为了提高竹笋产量,农民不合理地大量施用化肥,已造成土壤盐化、酸化,地力破坏,导致土壤磷钾大量残留,特别是氮磷的大量流失已造成了周边水体严重污染。虽然土壤DOC和DON在土壤全碳、全氮含量中所占的比例很小,但却是土壤有机质中最重要和最活跃的部分。因此本研究的目的旨在通过全年动态监测雷竹林渗漏水中溶解性有机碳(DOC)和溶解性有机氮(DON)浓度的变化,探明减量施用化肥和有机肥对减少雷竹林氮渗漏淋失负荷的作用,以便为解决雷竹生产上的面源污染问题提供理论依据。【方法】试验设置了5个处理为对照(CK)、常规施肥(CF)、减量有机肥(DO)、减量无机肥(DI)和减量有机无机肥(DOI),3次重复,随机区组设计,小区面积为100 m2。试验于5月18日、 9月7日、11月9日分别施用肥料总量的40%、30%和30%,施肥后均进行浅翻,深度5 cm左右。【结果】 不同施肥雷竹林中DOC及DON平均浓度为33.7~45.5 mg/L和6.6~12.6 mg/L,DOC和DON的渗漏流失负荷为84.5~138.2 kg/hm2和17.2~46.3 kg/hm2。DOC渗漏流失负荷大小顺序为常规施肥(138.2 kg/hm2)减量有机肥(133.7 kg/hm2)减量无机肥(120.9 kg/hm2)不施肥(99.8 kg/hm2)减量有机无机肥(84.5 kg/hm2),而DON渗漏流失负荷大小顺序为减量有机肥(46.3 kg/hm2)常规施肥(35.3 kg/hm2）减量有机无机肥(34.8 kg/hm2)减量无机肥(31.1 kg/hm2)不施肥(17.2 kg/hm2)。渗漏水中DOC(mg/L)与DON(mg/L)之间不存在显著相关性。【结论】大幅减少化肥和有机肥用量,并推广有机肥和无机肥配施,不仅维持了雷竹竹笋的较高产量,还能减少土壤养分损失,具有经济和环境双重效益,是雷竹合理施肥的发展方向。     

Yield and quality of tomato grown under organic and conventional nutrient management

Nutrient management plays an important role in yield and quality of tomatoes. A field experiment was conducted during the years 2008–09 and 2009–10 to analyze the effect of organic and conventional sources of fertilizer on yield and quality of tomatoes in an acid lateritic soil of India. The organic sources of fertilizer were vermicompost (VC), crop residue (CR), vermiwash (VW) and biofertilizer (BF). The conventional input was chemical fertilizer (CF) applied at recommended dose of 100:80:60 kg ha^?1 of N:P₂O₅:K₂O for the tomato. The organic source VC was used to supply 100% N recommendation as single source or 50% N recommendation when combined with CF or organic sources. Maximum fruit yield was recorded when CF was applied at full dose, which was on a par with VC at full recommendation. A higher percentage of large-size fruits (>7 cm) was obtained in VC-based treatments compared with CF treatment. Vermicompost at full dose increased ascorbic acid, beta carotene, total soluble solids and color value compared with its half dose along with other organic sources (CR, BF). The potential exists to improve tomato fruit quality through a better nutrient management, whether it be conventional, organic or a combination of both.     

不同施肥与生物质炭配施对水稻田面水氮磷流失及产量的影响

通过研究减氮施肥及施用生物质炭对田面水氮磷流失风险和水稻性状的影响,结果表明:不同施肥处理田面水总氮、溶解性氮、铵态氮浓度均在施肥后第2天达到最高,然后迅速下降,并于7d后趋于稳定,稳定后浓度分别是顶峰值的5.6％～16.3％,8.4％～23.7％和25.0％～46.1％;不同施肥处理田面水总磷浓度在施肥后第3天达到最高,而后迅速下降,一周后趋于稳定;可溶磷浓度在施肥后4～5 d内处于一个平稳的状态,而后平缓下降至施肥前水平.氮磷浓度在减氮(20％)施肥条件下与常规施肥相比均降低.减氮施肥对产量的影响不大,但减氮施肥结合生物质炭处理水稻产量与常规施肥相比提高了24.6％,达到7 391.5 kg/hm2;减氮施肥降低了氮素流失风险,但减氮施肥结合生物质炭处理则明显提高田面水中总磷的浓度,增加磷素流失的风险.在施肥后1周内是控制氮磷流失风险的最佳时期,此时若遇暴雨,将导致氮磷随径流大量流失.