本文選題：豆科綠肥　切入點(diǎn)：冬小麥　出處：《西北農(nóng)林科技大學(xué)》2016年博士論文　論文類型：學(xué)位論文

【摘要】：作為一個(gè)典型的雨養(yǎng)農(nóng)業(yè)地區(qū),我國(guó)黃土高原地區(qū)農(nóng)業(yè)生產(chǎn)的可持續(xù)發(fā)展不斷面臨著水分虧缺和土壤貧瘠所帶來(lái)的挑戰(zhàn)。夏閑期種植并翻壓綠肥作物不僅可以有效培肥地力、促進(jìn)后茬作物生長(zhǎng)和產(chǎn)量形成,同時(shí)能在時(shí)間和空間層面上提高養(yǎng)分、水分、光熱等自然資源的利用率,因此,本研究通過(guò)在渭北旱塬地區(qū)開(kāi)展長(zhǎng)期的田間定位試驗(yàn)(2008年~至今),深入研究黃土高原地區(qū)種植不同豆科綠肥(長(zhǎng)武懷豆、大豆和綠豆,夏季裸地休閑為對(duì)照)以及冬小麥生長(zhǎng)季不同施氮水平(0,108,135,162 kg N/ha)對(duì)土壤水分和氮素供應(yīng)的影響,初步探究豆科綠肥協(xié)調(diào)土壤水分和氮素供應(yīng)的效應(yīng)及機(jī)理,旨在為恢復(fù)并發(fā)展我國(guó)綠肥產(chǎn)業(yè)體系提供科學(xué)的理論依據(jù)和技術(shù)支撐。取得的主要結(jié)果如下:(1)通過(guò)4年的田間定位試驗(yàn)數(shù)據(jù),研究發(fā)現(xiàn)旱地連續(xù)多年種植并翻壓豆科綠肥較傳統(tǒng)的裸地夏休閑能夠有效促進(jìn)后茬冬小麥苗期的生長(zhǎng)(冬季單株分蘗數(shù)和春季總莖數(shù))、后期的產(chǎn)量形成(產(chǎn)量、生物量和公頃穗數(shù))和養(yǎng)分吸收狀況。然而,由于需要額外的勞動(dòng)成本和田間管理投入,豆科綠肥體系較高的生產(chǎn)成本嚴(yán)重影響該體系的經(jīng)濟(jì)效益。此外,施用氮肥較不施氮顯著提高旱地冬小麥生長(zhǎng)狀況、產(chǎn)量形成、養(yǎng)分吸收和經(jīng)濟(jì)效益,然而三種氮肥施用量間無(wú)顯著差異;(2)通過(guò)6年的田間定位試驗(yàn)結(jié)果并結(jié)合當(dāng)?shù)?7年的降雨氣象資料,詳細(xì)分析我國(guó)渭北旱源冬小麥種植區(qū)降雨時(shí)空分布特征,初步研究黃土高原地區(qū)不同降雨年型條件下應(yīng)用豆科綠肥對(duì)后茬冬小麥產(chǎn)量和水分利用效率的影響,同時(shí)探究豆科綠肥協(xié)調(diào)旱地土壤水分平衡的內(nèi)在機(jī)理。發(fā)現(xiàn)連續(xù)多年夏閑期種植豆科綠肥的確會(huì)消耗土壤水分,同時(shí)該措施會(huì)因降雨年型的不同而對(duì)后茬冬小麥產(chǎn)量帶來(lái)不同程度的影響。當(dāng)年降雨量較為豐沛時(shí),種植豆科綠肥所引起的夏閑期土壤水分虧缺能夠得到及時(shí)補(bǔ)充,豆科綠肥可增加旱地冬小麥生產(chǎn)量;反之,干旱年份則該措施將帶來(lái)嚴(yán)重的減產(chǎn)效果。整體來(lái)看,試驗(yàn)期間種植并翻壓豆科綠肥較夏休閑顯著提高冬小麥產(chǎn)量和水分利用率,平均提高幅度分別為13%和27%。同時(shí),豆科綠肥對(duì)促進(jìn)旱地土壤水分平衡也發(fā)揮著重要的作用;(3)結(jié)合長(zhǎng)達(dá)374天的豆科綠肥的腐解試驗(yàn),進(jìn)一步探究了豆科綠肥生育期所累積的氮素在旱地傳統(tǒng)的冬小麥種植體系中吸收、轉(zhuǎn)化和利用的內(nèi)在機(jī)制。研究發(fā)現(xiàn),試驗(yàn)期間平均每年豆科綠肥在其盛花期通過(guò)其地上部和根系生物量積累共計(jì)53~76 kg N/ha氮素,通過(guò)一年的翻壓還田,至少有32 kg N/ha綠肥氮素經(jīng)過(guò)土壤微生物的分解礦化作用釋放到周圍環(huán)境中;其中,約有7~27 kg N/ha最終被后茬的冬小麥吸收利用。整體來(lái)看,豆科綠肥體系平均每年氮素總投入量為164 kg N·ha-1·yr-1,氮素?cái)y出量平均為114 kg N·ha-1·yr-1,最終導(dǎo)致該體系每年約有50 kg N·ha-1·yr-1的氮素盈余在土壤中。旱地夏閑期應(yīng)用豆科綠肥能夠有效替代13~48%(平均為31%)的冬小麥生長(zhǎng)季無(wú)機(jī)氮肥用量。此外,連續(xù)4年種植豆科綠肥可降低夏閑期間土壤硝態(tài)氮向深層(100~200 cm)淋溶的風(fēng)險(xiǎn),平均降低硝態(tài)氮淋溶19.6 kg N/ha;(4)通過(guò)5年的田間試驗(yàn)結(jié)果,探究我國(guó)黃土高原地區(qū)應(yīng)用豆科綠肥對(duì)旱地麥田土壤碳庫(kù)和氮庫(kù)庫(kù)容的影響;同時(shí)采用One-compartment模型,對(duì)土壤有機(jī)碳庫(kù)周轉(zhuǎn)的動(dòng)態(tài)機(jī)制進(jìn)行了擬合。發(fā)現(xiàn)在黃土高原地區(qū)的夏閑期種植短期的豆科綠肥,其生物量及碳、氮養(yǎng)分累積與生長(zhǎng)周期呈極顯著的冪函數(shù)關(guān)系。經(jīng)過(guò)一年的腐解礦化,旱地麥田土壤中豆科綠肥地上部和根系的平均碳素殘留率分別為26%和33%;而相應(yīng)的平均氮素殘留率分別為31%和52%。與基礎(chǔ)土樣相比,夏閑期連續(xù)多年種植并翻壓豆科綠肥顯著提高旱地麥田表層土壤有機(jī)碳、活性有機(jī)碳和全氮含量以及相應(yīng)的庫(kù)容儲(chǔ)量。此外,試驗(yàn)第5年表層土壤有機(jī)碳庫(kù)儲(chǔ)量與平均每年作物碳還田量間呈現(xiàn)顯著的正相關(guān)關(guān)系,并且每年至少需要0.68 Mg C·ha-1·yr-1的作物碳還田量才能夠基本維持基礎(chǔ)土壤的有機(jī)碳庫(kù)儲(chǔ)量(19.04 Mg C/ha)。通過(guò)One-compartment模型,本研究計(jì)算出我國(guó)黃土高原地區(qū)旱地土壤有機(jī)質(zhì)的礦化速率(1%)和腐殖化系數(shù)(23%)。此外,我們預(yù)測(cè)需要近22年的時(shí)間該類型土壤的有機(jī)碳庫(kù)容才能達(dá)到周轉(zhuǎn)平衡狀態(tài),說(shuō)明目前土壤有機(jī)碳庫(kù)尚未達(dá)到飽和狀態(tài),還有繼續(xù)固持碳素的潛力和空間。整體來(lái)看,在黃土高原地區(qū)傳統(tǒng)的冬小麥-夏休閑體系中長(zhǎng)期引入綠肥作物能夠有效促進(jìn)冬小麥生長(zhǎng)和養(yǎng)分吸收、提高冬小麥生產(chǎn)力水平和水分利用效率,并能夠替代部分冬小麥生長(zhǎng)季的無(wú)機(jī)氮肥施用量;同時(shí),種植豆科綠肥能夠有效降低土壤礦質(zhì)氮向深層淋溶的風(fēng)險(xiǎn),并顯著提高旱地表層土壤肥力水平。因此,在黃土高原地區(qū)發(fā)展綠肥產(chǎn)業(yè)體系具有一定的可行性,同時(shí)將對(duì)我國(guó)發(fā)展穩(wěn)產(chǎn)高效、環(huán)境友好型的現(xiàn)代化農(nóng)業(yè)帶來(lái)深遠(yuǎn)的影響。
[Abstract]:As a typical rainfed agriculture area, sustainable development of agriculture in the Loess Plateau of China are facing water shortage and poor soil brought challenges. During the summer fallow period and planting green manure crops can not only effectively improve soil fertility and crop growth and yield formation to promote, and can improve the nutrient in time and space aspects of water, utilization of natural resources such as heat rate, therefore, this study was carried out through the long-term test in Weibei dryland (2008 - present), different planting green manure legume research area of the Loess Plateau (Huai bean, soybean and mung bean, summer fallow and winter wheat as control) the growing season of different nitrogen levels (0108135162 kg N/ha) effects on soil water and nitrogen supply, preliminary study on effect and mechanism of coordination of leguminous green manure soil moisture and nitrogen supply, to The recovery and development of China's green industry system to provide theoretical basis and technical support of science. The main results are as follows: (1) through the field test data of 4 years, the study found that in successive years and planting leguminous green manure than the traditional bare summer leisure can effectively promote the following winter wheat seedling growth (winter the number of tillers per plant and total stem number), spring late yield (yield, biomass and spike number) and nutrient uptake. However, due to the need for additional labor cost and field management system, serious leguminous green manure higher production costs affect the system economic benefits. In addition, less nitrogen fertilizer nitrogen fertilization significantly improve dryland winter wheat growth status, yield, nutrient absorption and economic benefits, however, there was no significant difference between the three kinds of nitrogen fertilizer; (2) through 6 years of field test results when combined with Rainfall meteorological data of 57 years, a detailed analysis of the Weibei Dry land winter wheat planting characteristics of temporal and spatial distribution of rainfall area, the yield and water use efficiency of winter wheat using leguminous green manure in different rainfall years preliminary study on the condition of loess plateau area, and explore the internal mechanism of leguminous green manure in upland soil water balance and coordination for many consecutive years. Found in summer fallow period of leguminous green manure will deplete the soil moisture at the same time, the measures for different rainfall types and the yield of winter wheat stubble bring about different effects. When the rainfall is abundant, planting leguminous green manure in summer fallow period caused by soil water deficit can be added in a timely manner, Leguminosae green manure can increase the yield of Winter Wheat in dryland; on the contrary, the drought measures will bring serious production effects. Overall, during the test of planting and turning over green fertilizer than legume The summer fallow significantly increased winter wheat yield and water utilization rate, the average increase rate was 13% and 27%. respectively. At the same time, green manure on soil water balance in Dryland promotion also plays an important role; (3) with 374 days of leguminous green manure decomposition test, nitrogen and further explore the growth period of leguminous green manure accumulated in planting system of Winter Wheat in Dryland in the traditional absorption mechanism of transformation and utilization. The study found that the average annual leguminous green manure during the test in its flowering through the shoot and root biomass accumulation of total nitrogen by 53~76 kg N/ha, returning pressure over a year, at least 32 kg N/ha nitrogen mineralization after decomposition of green manure the soil microorganisms released to the surrounding environment; among them, there are about 7~27 kg N/ha was eventually after the winter wheat crop absorption and utilization. Overall, the average annual total investment of legume nitrogen 1 system 64 kg N - HA-1 - yr-1, nitrogen uptake averaged 114 kg N - HA-1 - yr-1, eventually lead to nitrogen surplus of approximately 50 kg of N - HA-1 - yr-1 system of the year in the soil. In summer fallow period application of leguminous green manure can effectively replace 13~48% (average 31%) season of inorganic nitrogen fertilizer the growth of winter wheat. In addition, 4 consecutive years of leguminous green manure in summer fallow period can reduce soil nitrate nitrogen to the deep layer (100~200 cm) leaching risk, reduce the average nitrate leaching to 19.6 kg N/ha; (4) through the field test results of 5 years, to explore the application of leguminous green manure on the Loess Plateau in China effect of dry soil carbon and nitrogen storage capacity; at the same time using the One-compartment model, the dynamic mechanism of soil organic carbon turnover fitting. Found in the Loess Plateau during summer fallow planting short bean green manure, biomass and carbon, nitrogen accumulation and growth cycle A very significant power function relationship. After a year of decomposition of carbon mineralization, average shoot and root soil in dryland wheat, the residual rate of legumes were 26% and 33%; and the average nitrogen corresponding residual rate was 31% compared with 52%. and foundation soil samples in summer fallow period and planting pressure over consecutive years leguminous green manure significantly improve dryland wheat, soil organic carbon, labile organic carbon and total nitrogen content and storage reserves accordingly. In addition, there is a significant positive correlation between the test surface fifth years reserves of soil organic carbon pool and the average annual crop carbon residue amount, organic carbon storage and annual crop carbon returning amount of at least 0.68 Mg C HA-1 yr-1 can maintain the basic foundation soil (19.04 Mg C/ha). Through the One-compartment model, this study calculates the mineralization rate in China Loess Plateau Dryland Soil organic matter (1%) and rot Colonization factor (23%). In addition, we predict the need for nearly 22 years the soil organic carbon storage in order to achieve turnover equilibrium, the soil organic carbon library has not yet reached saturation, and continue holding carbon potential and space. Overall, the introduction of long-term green manure crops can effectively promote the growth and nutrition of winter absorption of wheat in the Winter Wheat Yellow Soil Plateau traditional summer fallow system, improve Winter Wheat Productivity and water use efficiency, and can replace part of winter wheat growing season of inorganic nitrogen; at the same time, the risk of leguminous green manure can effectively reduce soil mineral nitrogen to deep leaching, and significantly improve the fertility level of the surface Dryland Soil in the Loess Plateau region. Therefore, the development of green industry system has certain feasibility, while the stable development of our country's modern efficient, environment friendly Agriculture has a far-reaching impact.

【學(xué)位授予單位】：西北農(nóng)林科技大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：S55;S512.11
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本文編號(hào)：1628977