發(fā)布時(shí)間：2018-04-12 09:32

  本文選題：半干旱區(qū) + 土壤水分�。� 參考：《西北農(nóng)林科技大學(xué)》2017年博士論文

【摘要】：水肥是限制旱區(qū)作物產(chǎn)量提升的兩大重要因子,而合理密植是作物高產(chǎn)栽培的基礎(chǔ)。農(nóng)田集雨種植模式是一種適用于西北旱作農(nóng)田的高效用水栽培措施,可有效提高降雨利用效率,改善旱地作物的水分狀況。為完善和拓展集雨種植技術(shù)在旱區(qū)的運(yùn)用,進(jìn)一步挖掘其在旱地農(nóng)田的水分生產(chǎn)潛力,本研究以半干旱區(qū)傳統(tǒng)栽培作物-谷子為對(duì)象,從施肥量?jī)?yōu)化和群體調(diào)控兩方面著手,對(duì)我國(guó)西北典型的半干旱區(qū)(寧夏彭陽(yáng)縣)農(nóng)田集雨種植模式下谷子的高效栽培方案進(jìn)行了探索。通過(guò)研究不同種植方式下(集雨種植和平作)施肥量(無(wú)肥、低肥、中肥和高肥)和密度(低密度、中密度和高密度)對(duì)農(nóng)田水分養(yǎng)分狀況、谷子生長(zhǎng)、產(chǎn)量形成、水肥利用效率的影響,取得如下主要研究結(jié)果:1、不同種植模式下施肥量和密度對(duì)農(nóng)田水分的影響(1)相較于平作,集雨種植方式通過(guò)壟面覆膜可有效的蓄積降雨減少農(nóng)田水分的無(wú)效損失,無(wú)論在豐水年還是平水年,均可提高谷子各生育階段0-200 cm土層的土壤水分含量。在平水年,集雨種植提高了谷子間苗期和孕穗期0-60 cm土層的土壤含水量,分別較平作提高了6.8-7.0%和6.5-30.7%,隨生育進(jìn)程的推進(jìn),谷子的耗水深度增加,在灌漿和收獲期集雨種植改善了深層土壤水分含量。集雨種植減少了農(nóng)田總蒸散量,在2013-2015年分別平均較平作減少了5.4%(27.7 mm)、11.1%(41.4 mm)和8.5%(35.1mm)。(2)增施肥料和加大種植密度均會(huì)增加谷子對(duì)土壤水分的消耗,降低耗水深度土層的土壤水分含量,年際間的表現(xiàn)受降雨特征和農(nóng)田基礎(chǔ)肥力的影響。在2013年,由于拔節(jié)期降雨較多,施肥量和密度處理對(duì)土壤水分的影響主要表現(xiàn)在灌漿期和收獲期,隨施肥量和種植密度的增大,谷子耗水量均呈顯著增加趨勢(shì),從而導(dǎo)致土壤水分含量的降低;在2014年,施肥處理間的土壤水分差異主要表現(xiàn)在灌漿期和收獲期,各施肥量水平下,土壤水分含量隨種植密度的增加表現(xiàn)為明顯降低趨勢(shì);在2015年,密度對(duì)谷子耗水的影響主要表現(xiàn)在營(yíng)養(yǎng)生長(zhǎng)階段,施肥對(duì)谷子耗水的影響則表現(xiàn)在全生育階段,孕穗和灌漿期的土壤水分隨種植密度和施肥量的增大而降低,但在收獲期,平作模式下土壤水分受種植密度因素的影響不明顯,集雨種植下中密和高密處理間的土壤水分含量差異不明顯,但均小于低密度。2、不同種植模式下施肥量和密度對(duì)谷子生長(zhǎng)的影響(1)三年試驗(yàn)均表明施肥可促進(jìn)谷子的生長(zhǎng),顯著增大了谷子的株高、莖粗、單株葉面積和葉面積指數(shù)(LAI),進(jìn)而提高了個(gè)體和群體的干物質(zhì)積累量,當(dāng)施肥超過(guò)中等施肥量(n186kg·ha-1+p2o596kg·ha-1)后,進(jìn)一步增大施肥量對(duì)谷子植株生長(zhǎng)的促進(jìn)效果不明顯。種植密度對(duì)谷子個(gè)體生長(zhǎng)指標(biāo)的影響大致表現(xiàn)為顯著的負(fù)效應(yīng),但群體生長(zhǎng)指標(biāo),如lai和群體干物質(zhì)積累量均隨密度的增大大致呈增加趨勢(shì),在2015年由于農(nóng)田水肥條件較差,密度處理對(duì)群體干物質(zhì)積累量的影響不明顯。同一密度水平下,集雨種植促進(jìn)谷子個(gè)體生長(zhǎng),株高、莖粗、單株葉面積均顯著高于平作,但由于單位面積群體數(shù)量低于平作,lai、群體干物質(zhì)積累量等群體指標(biāo)均顯著低于平作。(2)在平水年,營(yíng)養(yǎng)器官干物質(zhì)的轉(zhuǎn)運(yùn)量和轉(zhuǎn)移率均隨施肥量的增大大致呈先增加后降低的趨勢(shì),在低量或中量施肥下達(dá)到最大,過(guò)高的施肥量不利于營(yíng)養(yǎng)器官干物質(zhì)向籽粒的轉(zhuǎn)運(yùn),導(dǎo)致轉(zhuǎn)換率的降低。增大密度能夠增大營(yíng)養(yǎng)器官的群體干物質(zhì)轉(zhuǎn)運(yùn)量,轉(zhuǎn)移率和轉(zhuǎn)換率的表現(xiàn)因施肥量不同而異。相較于平作,集雨種植顯著提高了各營(yíng)養(yǎng)器官的干物質(zhì)轉(zhuǎn)移率,促進(jìn)了干物質(zhì)向籽粒的轉(zhuǎn)運(yùn),營(yíng)養(yǎng)器官干物質(zhì)的轉(zhuǎn)換率在2014和2015年分別提高了14.7%和61.0%。3、不同種植模式下施肥量和密度對(duì)谷子產(chǎn)量形成及水分利用效率的影響(1)施肥可顯著提高谷子產(chǎn)量和水分利用效率(wue),當(dāng)施肥量超過(guò)中肥(n186kg·ha-1+p2o596kg·ha-1)后,收獲指數(shù)呈下降趨勢(shì),肥料的農(nóng)學(xué)利用效率和偏生產(chǎn)力均顯著下降,兩種種植模式下的谷子產(chǎn)量和wue在平水年的增幅不顯著,而平作模式下的谷子產(chǎn)量和wue在豐水年增幅顯著(p0.05)。施肥較不施肥顯著提高谷子千粒質(zhì)量,但進(jìn)一步增大施肥量主要是通過(guò)提高穗粒數(shù)來(lái)實(shí)現(xiàn)增產(chǎn)的。(2)在養(yǎng)分充足的條件下,增大種植密度可顯著提高豐水年型下谷子的產(chǎn)量、wue及肥料利用效率;在平水年,過(guò)高的種植密度會(huì)導(dǎo)致?tīng)I(yíng)養(yǎng)生長(zhǎng)對(duì)土壤水分的過(guò)度消耗,不利于最終谷子籽粒產(chǎn)量的形成,導(dǎo)致收獲指數(shù)和wue的顯著下降。同一種植密度水平下,本研究集雨種植下單位面積的留苗株數(shù)較平作減少了25%,在施肥量充足的條件下,應(yīng)通過(guò)適當(dāng)增大種植密度來(lái)增加集雨種植下單位面積的成穗數(shù)來(lái)提高產(chǎn)量和wue,豐水年建議采取高密度種植(行距30cm、株距5.5cm),平水年應(yīng)適當(dāng)降低種植密度,以中密度(行距30cm、株距7.5cm)為宜;對(duì)平作種植而言,種植密度超過(guò)中密度后,進(jìn)一步增密對(duì)產(chǎn)量和wue的提升效果不顯著,在地力偏差的農(nóng)田甚至減產(chǎn)。(3)在豐水年,集雨種植較平作呈減產(chǎn)趨勢(shì),隨施肥量和密度的增大,產(chǎn)量及wue的減幅呈增大趨勢(shì),在高肥高密水平下,r較t的產(chǎn)量和wue分別降低14.3%和11.4%;在平水年,在適宜的種植密度下,集雨種植表現(xiàn)為增產(chǎn)趨勢(shì),在中量施肥和公頃留苗株數(shù)均為33.3萬(wàn)株的種植密度下,2014和2015年產(chǎn)量較平作分別提高了8.0%和6.1%。4、不同施肥量對(duì)集雨種植和平作模式下谷子養(yǎng)分吸收、轉(zhuǎn)運(yùn)及利用效率的影響(1)隨施肥量的增大,谷子植株各器官的氮磷養(yǎng)分積累量均呈增大趨勢(shì),而氮磷素對(duì)籽粒的貢獻(xiàn)率呈先增加后降低的趨勢(shì),在低量或中量施肥下達(dá)到最大;花前氮磷素的轉(zhuǎn)移率、氮磷素的吸收效率(nupe/pupe)、收獲指數(shù)(nhi/phi)和利用效率(nue/pue)均呈降低趨勢(shì)。(2)在單位面積留苗株數(shù)一致的水平下(33.33萬(wàn)株/公頃),在平水年,集雨種植較平作提高了開(kāi)花期谷子植株各器官的氮磷素積累量及氮磷素的花前轉(zhuǎn)移率;在收獲期,集雨種植下各營(yíng)養(yǎng)器官的氮磷素積累量均低于平作,籽粒的氮磷素積累量顯著高于平作,提高了花前氮磷素對(duì)籽粒的貢獻(xiàn)率,但兩種種植方式下的植株總氮磷素的積累量差異不顯著;集雨種植下的氮磷素吸收效率、收獲指數(shù)和利用效率均高于平作。在豐水年,兩種種植模式間的氮磷素積累量和利用效率差異不明顯。5、不同施肥量對(duì)集雨種植和平作模式下速效養(yǎng)分殘留的影響(1)施肥可增加谷子抽穗期土壤硝態(tài)氮?dú)埩袅?為生殖生長(zhǎng)提供充足的養(yǎng)分環(huán)境。硝態(tài)氮淋溶深度隨生育期降雨量的增多而加深,收獲期硝態(tài)氮淋溶的最大積累峰均在60cm以下土層,豐水年可達(dá)120 cm,當(dāng)施肥量超過(guò)中肥水平后,硝態(tài)氮的殘留濃度呈明顯的增加趨勢(shì);相較于平作,在中高施肥量水平下,集雨種植下土壤硝態(tài)氮的殘留濃度明顯增大,淋溶深度較平作增加了20 cm左右,過(guò)量施肥會(huì)相對(duì)增大集雨種植模式下土壤硝態(tài)氮的深層淋溶風(fēng)險(xiǎn)。(2)收獲期土壤有效磷主要集中在0-20 cm土層,隨施肥量的增加含量呈顯著增加趨勢(shì),在中量施肥水平下,有效磷的含量即可達(dá)到5.0 mg kg-1以上,能夠維持土壤磷素的平衡。通過(guò)施肥量?jī)?yōu)化和種植密度調(diào)控可有效提升谷子集雨種植模式下的產(chǎn)量及水肥利用效率,綜合分析認(rèn)為,在年降雨量為400 mm左右的半干旱區(qū),谷子高產(chǎn)栽培的適宜施肥水平大致為中肥,即每公頃施氮186 kg、施磷96 kg,可兼顧高產(chǎn)與肥料的高效利用;集雨種植模式下應(yīng)當(dāng)通過(guò)適當(dāng)增大種植溝內(nèi)的種植密度來(lái)提升谷子增產(chǎn)潛力及水肥利用效率,大同29號(hào)品的適宜種植密度為行距30 cm、株距7.5 cm,即公頃留苗數(shù)為33.33萬(wàn)株。
[Abstract]:Water and fertilizer are two important limiting factor in arid crop yield improvement, which is the basis of rational close planting cultivation of crops. Farmland planting pattern is suitable for northwest dry farmland cultivation measures of high efficient water use, can effectively improve the rainfall use efficiency, improve water status of dryland crops. In order to improve and expand the planting technology in the arid areas of application, further mining in water production potential of farmland, based on the traditional cultivation crop in semi arid area of millet as the object, from two aspects of fertilizer optimization and population control on China's North West typical semi-arid region (Ningxia Pengyang county) in farmland cultivation scheme of planting pattern under the millet was explored. Through the way of study under different planting (planting peace) fertilization (no fertilizer, low fat, high in fertilizer and fertilizer) and density (low density, high in density and density) of agricultural Water and nutrient status of field millet growth, yield formation, effect of water and fertilizer use efficiency, obtained the following results: 1, the influence of fertilization and density on soil moisture under different planting patterns (1) compared with flat planting, planting way through the ridge covered with plastic can effectively reduce the loss of soil moisture accumulation rainfall is invalid no matter, or in the wet year water level, can improve the soil moisture content of millet in different growth stages of 0-200 cm soil layer. The water level, planting millet increased between seedling stage and booting stage 0-60 cm soil layer soil moisture, respectively compared with the flat was increased by 6.8-7.0% and 6.5-30.7%, along with the growth of the to promote, millet water consumption depth increased, in filling and harvest planting improved soil water content. Planting reduced evapotranspiration, in 2013-2015 years were reduced by 5.4% than the average level (27.7 mm), 11.1 % (41.4 mm) and 8.5% (35.1mm). (2) increasing fertilizer and increasing planting density increased millet consumption of soil moisture, the soil water content decreased water consumption depth, the annual performance influenced by rainfall characteristics and basic farmland fertility. In 2013, the feast of pulling more rain and the effect of fertilization and density on soil moisture mainly in the grain filling period and harvest period, with the increase of the amount of fertilizer and planting density, millet water consumption increased significantly, resulting in the reduction of soil moisture content; in 2014, soil moisture difference between fertilization mainly in the grain filling period and harvest the level of each period, fertilization, soil moisture content increased with the increase of planting density showed obvious decreasing trend; in 2015, the effect of density on water consumption of millet mainly in the vegetative stage, effects of Fertilization on water consumption of millet in the performance The whole growth stage, soil moisture at booting and filling stage decreased with the increase of planting density and fertilizer quantity, but in the harvest period, average soil moisture patterns affected by planting density factors is not obvious, planting density and differences in soil moisture content and high density treatments was not obvious, but less than the low the density of.2, the effect of fertilization and density on growth of millet under different planting patterns (1) three years test showed that fertilization could promote the growth of millet, millet significantly increased the plant height, stem diameter, leaf area and leaf area index (LAI), and then improve the individual and collective accumulation the material, when fertilization over medium fertilization (n186kg ha-1+p2o596kg HA-1), further increase of the amount of fertilizer on Millet plant growth promoting effect is not obvious. The effect of planting density on the growth index of millet individual is approximately expressed as a significant negative effect, but the group The growth index, such as dry matter accumulation increased with the density increasing and increased Lai Group in 2015 due to poor soil fertility conditions, the density effect on dry matter accumulation of groups is not obvious. The same density level, planting millet to promote individual growth, plant height, stem diameter, leaf the area was significantly higher than that of flat, but because of the number of groups per unit area is lower than that of flat, Lai, dry matter accumulation and population index were significantly lower than that of flat groups. (2) the water level, vegetative organs dry matter translocation amount and transfer rate increased with the increase of the amount of fertilizer was increased first and then decreased the trend, reached the maximum in low volume or amount of fertilization, fertilization is not conducive to high dry matter translocation to grain nutritional organs, cause the conversion rate decreased. Increasing the density of vegetative organs of groups can increase the amount of dry matter transferred, the transfer and conversion rate. The performance for fertilization varies. Compared with flat planting, planting significantly increased the vegetative organs dry matter transfer rate, promote the dry matter translocation to grain, vegetative organs dry matter conversion rate of 14.7% and 61.0%.3 were increased in 2014 and 2015, different planting mode of fertilization and density formation and water use efficiency of Millet Yield (1) fertilization can significantly increase the yield and water use efficiency of Millet (WUE), when the amount of fertilizer than in fertilizer (n186kg ha-1+p2o596kg HA-1), harvest index decreased, fertilizer agronomy utilization efficiency and partial factor productivity decreased significantly, growing two under the mode of Millet Yield and WUE was not significant in the average year increase, while flat mode Millet Yield and WUE in wet year increased significantly (P0.05). Compared with the treatments of fertilization significantly increased millet 1000 grain weight, but further increase of the amount of fertilizer Mainly by increasing the grain number per spike increase. (2) in nutrient rich conditions, the increase of planting density can significantly improve the rainy years under Millet Yield, WUE and fertilizer use efficiency; the water level, high planting density will lead to excessive consumption of vegetative growth on soil moisture, is not conducive to the formation of the final grain yield of millet, resulting in a significant decrease in harvest index and WUE. The same planting density levels in the study area, planting under the unit number of the left seedling is flat as reduced by 25% in the amount of fertilizer in adequate condition should be set to increase the area of planting unit's spike to improve the yield and WUE by increasing planting density, wet year recommended high planting density (row spacing of 30cm, 2 and 5.5cm), water level should be reduced to planting density, medium density (row spacing of 30cm, 2 and 7.5cm) is appropriate; planting on flat, planting density Over the medium density, further increasing the density on the yield and enhance the WUE effect is not remarkable, even cut in fertility of farmland. The deviation (3) in wet year, planting a flat declined with the increase of the amount of fertilizer and density, yield and WUE reduction increases in high fertility high level, R is t and WUE yield were reduced by 14.3% and 11.4%; the water level, the suitable planting density, planting showed increase trend in fertilization and the number of the left seedling were 333 thousand hectares were planting density, the yield is flat in 2014 and 2015 respectively increased by 8% and 6.1%.4, different fertilization on planting mode for peace millet nutrient absorption, transport and utilization efficiency (1) with the increase of the amount of fertilizer, nitrogen and phosphorus accumulation in different organs of Foxtail Millet plant increased, and nitrogen and phosphorus in the contribution rate to grain increased after reduce 鐨勮秼鍔，

本文編號(hào)：1739170