长期轮作与施肥对土壤肥力的影响及其综合评价

发布时间：2018-01-12 06:25

  本文关键词：长期轮作与施肥对土壤肥力的影响及其综合评价　出处：《西北农林科技大学》2016年博士论文　论文类型：学位论文

  更多相关文章： 轮作 土壤肥力 数值化 综合评价

【摘要】：轮作与施肥是旱作农业区提高粮食产量、促进土壤养分平衡、提高水肥资源利用效率的重要措施。论文针对黄土高原旱作农田土壤肥力需要提升这一核心问题,在长期轮作与施肥定位试验基础上,对耕层土壤的物理、养分及生物学性质进行全面的比较和分析,探讨长期定位施肥对构成土壤肥力水平各因素的影响,采用模糊数学综合评价法对不同轮作系统的土壤肥力进行了数值化综合评价,探讨了不同轮作与施肥系统27年后的土壤肥力水平,并分析了土壤肥力水平与作物产量的相关性。取得的主要结论如下:1.作物长期轮作与施肥能改善土壤的紧实度和通气状况。轮作27年后,休闲地的土壤紧实度偏紧(容重为1.29 g·cm-3),苜蓿单施磷肥(容重为0.97 g·cm-3)及施NPM(容重为0.99 g·cm-3)的土壤过松。苜蓿连作条件下单施有机肥、施NPM的土壤孔隙度比休闲地分别增加了11.39%、10.20%;小麦连作条件下单施有机肥的土壤孔隙度比休闲地高9.15%;在NPM配施条件下粮豆轮作的土壤孔隙度比休闲地高8.87%,粮饲轮作的土壤孔隙度比休闲地高7.95%。2.苜蓿连作比其他轮作系统更有利于土壤有机质的积累;不同轮作系统中,NPM配施比其他施肥处理更有利于土壤有机质的积累。苜蓿连作不施肥、单施磷肥及施NPM的土壤有机质含量分别为29.87 g·kg-1、28.08 g·kg-1、41.04g·kg-1,苜蓿连作施NPM的土壤有机质含量最高;小麦连作8个施肥处理中,施NM及施NPM较有利于土壤有机质的积累,分别为20.37 g·kg-1和20.98 g·kg-1。苜蓿连作比其他轮作系统更有利于土壤氮素的积累;不同轮作系统中,均为施NPM比其他施肥方式更有利于土壤氮素的积累。苜蓿连作条件下,不施肥、单施磷肥及施NPM的土壤全氮含量分别为2.05 g·kg-1、1.86 g·kg-1、2.59g·kg-1,土壤速效氮含量分别为129.27 mg·kg-1、114.86 mg·kg-1、163.34 mg·kg-1;小麦连作8个施肥处理中,施NM、NPM的全氮含量分别为1.31 g·kg-1和1.40 g·kg-1,速效氮含量分别为75.13mg·kg-1和73.98 mg·kg-1。施NPM有利于土壤磷的积累;施NPM条件下,试验中不同轮作系统对磷素的累积效应依次是苜蓿连作粮豆轮作粮饲轮作小麦连作玉米连作。在施NPM条件下,苜蓿连作的土壤全磷含量为1.13 g·kg-1,速效磷含量为68.14 mg·kg-1;小麦连作的土壤全磷及速效磷含量分别为1.03 g·kg-1和40.64 mg·kg-1;玉米连作的全磷及速效磷含量分别为0.92 g·kg-1和26.76 mg·kg-1;粮豆轮作的土壤全磷及速效磷含量分别为1.07g·kg-1和47.29 mg·kg-1,粮饲轮作的土壤全磷及速效磷含量分别为1.03 g·kg-1和42.95 mg·kg-1。施用有机肥的土壤速效钾含量较高,土壤速效钾含量达到一级水平;未施用有机肥的土壤速效钾含量较低,为二级或三级水平;施NPM条件下,苜蓿连作、小麦连作的土壤速效钾含量高于玉米连作、粮豆轮作及粮饲轮作。苜蓿连作施NPM的土壤速效钾含量为488.34 mg·kg-1,小麦连作施有机肥的处理M、PM、NM、NPM的土壤速效钾含量分别为470.50 mg·kg-1、309.58 mg·kg-1、547.02 mg·kg-1、500.53 mg·kg-1;粮豆轮作及粮饲轮作系统中施NPM的土壤速效钾为301.82 mg·kg-1、427.61 mg·kg-1。3.土壤蔗糖酶、磷酸酶及脲酶的酶活性对轮作与施肥措施响应敏感;苜蓿连作有利于土壤蔗糖酶、磷酸酶、脲酶活性提高;施用有机肥有利于磷酸酶活性的提高。4.土壤蔗糖酶活性、磷酸酶活性、脲酶活性及过氧化氢酶活性均与土壤有机质、全氮及速效氮含量呈极显著线性相关;土壤磷酸酶活性与土壤全磷、速效磷及速效钾均呈极显著线性相关;土壤过氧化氢酶活性与土壤全磷及速效钾含量显著线性相关。土壤蔗糖酶活性与土壤速效氮含量相关性最高,相关系数为0.4462(P0.01);土壤磷酸酶活性与速效氮含量的相关性最高,相关系数为0.7228(P0.01);土壤脲酶活性与土壤速效氮含量相关性最高,相关系数为0.6379(P0.01);土壤过氧化氢酶活性与全氮含量的相关性最高,相关系数为0.3345(P0.01)。5.粮草8年轮作8个处理间的土壤细菌、真菌、放线菌数量差异明显,粮草3年轮作的3个处理间的土壤细菌、真菌、放线菌数量差异不明显。轮作与施肥系统的土壤细菌、真菌、放线菌数量普遍高于休闲地,小麦连作单施N的土壤真菌,粮草8年轮作系统中马铃薯茬土壤放线菌数量均略低于休闲地,其原因有待于进一步研究。6.苜蓿连作或施用有机肥有利于培肥土壤,苜蓿连作条件下不施肥、单施磷肥及施NPM的土壤肥力IFI分别为71.35、71.20、87.87,小麦连作、玉米连作、粮草8年轮作、粮草3年轮作、粮豆轮作、粮饲轮作的土壤肥力IFI低于70.00。有机肥与化肥合理配合施用能更好的发挥肥料培肥土壤的作用。小麦连作施肥8个处理中,施用有机肥(M、PM、NM、NPM)处理的土壤肥力IFI分别为55.15、54.92、60.62、63.13,未施有机肥(CK、N、P、NP)处理的土壤肥力IFI分别为40.02、39.65、46.43、47.46。
[Abstract]:Crop rotation and fertilization is to increase food production in dry farming areas, improving soil nutrient balance, an important measure to improve the utilization efficiency of water and fertilizer. The soil fertility of dry farmland in the Loess Plateau to enhance the core problem, based on long-term rotation and fertilization experiment, the soil physical, conduct a comprehensive comparison and analysis of nutrients and to investigate the biological properties, effect of long-term fertilization on the composition of soil fertility factors, the numerical evaluation on soil fertility of different rotation system by using fuzzy comprehensive evaluation method, discusses the soil fertility level after 27 years of different fertilization and rotation system, and analyzes the relationship between soil fertility and crop yield. The main conclusions are as follows: 1. crop long-term rotation and fertilization can improve soil compactness and ventilation conditions. After 27 years of rotation, leisure places The soil compaction tight (bulk density is 1.29 G - cm-3), alfalfa P (bulk density was 0.97 G - cm-3) and NPM (bulk density was 0.99 G - cm-3) of the soil loose. Alfalfa under organic fertilizer application, soil porosity NPM than fallow were increased by 11.39%, 10.20%; continuous wheat under soil porosity of organic fertilizer is 9.15% higher than fallow soil porosity; crop legume rotation conditions than fallow 8.87% in NPM with high porosity, soil grain and forage rotation than leisure more than other high 7.95%.2. alfalfa cropping rotation system for soil organic matter accumulation in different rotation system; NPM than other treatments, more conducive to the accumulation of soil organic matter. Alfalfa continuous cropping without fertilization, soil organic matter content of P and NPM were 29.87 G - kg-1,28.08 G - kg-1,41.04g - kg-1, the soil organic matter of Alfalfa NPM The highest content of wheat cropping; 8 fertilizer treatments, NM and NPM fertilizer was beneficial to the accumulation of soil organic matter, were 20.37 g kg-1 and 20.98 g kg-1. more than other alfalfa continuous cropping rotation system for soil nitrogen accumulation; different rotation systems, both for the application of NPM to more than other treatments the soil nitrogen accumulation. Under the conditions of continuous cropping alfalfa, fertilization, soil total nitrogen content P and NPM were 2.05 G - kg-1,1.86 G - kg-1,2.59g - kg-1, the content of soil available nitrogen were 129.27 Mg - kg-1114.86 Mg - kg-1163.34 Mg - kg-1; small as Ludovic Magnin in the 8 fertilization treatments NM the total nitrogen content of NPM was 1.31 g kg-1 and 1.40 g kg-1, the content of available nitrogen were 75.13mg kg-1 and 73.98 mg kg-1. NPM applied to soil phosphorus accumulation; application of NPM under the condition of test in different rotation system on the effect of phosphorus accumulation should be followed Continuous cropping alfalfa crop legume rotation forage rice rotation continuous wheat maize continuous cropping. Under NPM conditions, the soil total phosphorus content of alfalfa was 1.13 G - kg-1, available phosphorus content was 68.14 mg kg-1; the content of total phosphorus and available phosphorus in wheat continuous cropping soil were 1.03 g kg-1 and 40.64 mg kg-1; total phosphorus and available phosphorus content in maize continuous cropping were 0.92 g kg-1 and 26.76 mg kg-1; the content of total phosphorus and available phosphorus in the soil crop legume rotation were 1.07g kg-1 and 47.29 mg kg-1, the content of total phosphorus and available phosphorus in forage rice rotation soil were 1.03 g and 42.95 Mg - kg-1. - kg-1 the application of organic fertilizer soil available potassium content, soil available potassium content did not reach the first level; the content of available potassium in soil organic fertilizer was low, two for grade three or NPM; under the condition of continuous cropping alfalfa, the content of soil available potassium was higher than that of continuous wheat continuous cropping of corn grain, soybean rotation And forage crops. Soil available potassium of Alfalfa NPM application was 488.34 Mg - kg-1, M continuous wheat fertilizer, organic fertilizer PM, NM, NPM content of soil available potassium was 470.50 Mg - kg-1309.58 Mg - kg-1547.02 Mg - kg-1500.53 Mg - kg-1; soil available potassium NPM grain soybean rotation and forage rice rotation system was 301.82 mg - kg-1427.61 Mg - kg-1.3. soil invertase, phosphatase and urease activity in response to sensitive to rotation and fertilization measures; continuous cropping alfalfa is beneficial to soil invertase, phosphatase, urease activity increased; organic fertilizer is beneficial to improve the activity of the.4. phosphatase activities of soil invertase, phosphatase the activity of urease activity and catalase activity and soil organic matter, was a significant linear correlation between the total nitrogen and available nitrogen content; soil phosphatase activity and soil total phosphorus, was a significant linear correlation between available phosphorus and available potassium soil; The soil catalase activity and soil total phosphorus and available potassium content were significant linear correlation. Soil invertase activity and soil available nitrogen content in the highest correlation, the correlation coefficient was 0.4462 (P0.01); soil phosphatase activity and available nitrogen content in the highest correlation, the correlation coefficient was 0.7228 (P0.01); soil urease activity and soil available nitrogen content correlation the highest correlation coefficient was 0.6379 (P0.01); catalase activity and total nitrogen content in soil had the highest correlation, the correlation coefficient was 0.3345 (P0.01) of soil bacteria,.5. forage 8 years rotation among the 8 treatments of fungi, actinomycetes significantly, soil bacteria, 3 forage processing 3 years rotation between fungi the number of actinomycetes, the difference is not obvious. Soil bacteria, crop rotation and fertilization system of fungi, actinomycetes was higher than that of fallow, soil fungi in wheat continuous cropping single nitrogen N, potato food 8 years rotation system Stubble soil actinomycetes were slightly lower than that of leisure, the reasons need to be further studied.6. or alfalfa organic fertilizer to the soil fertility, alfalfa continuous cropping without fertilization, soil fertility and fertilizer P IFI NPM 71.35,71.20,87.87 respectively, wheat continuous cropping, maize continuous cropping 8 years, forage rotation, forage 3 years of crop rotation, crop legume rotation, soil fertility IFI forage rice rotation was lower than that of 70.00. organic fertilizer and chemical fertilizer combined application can better play the role of soil fertilizer. 8 wheat continuous fertilization treatment, application of organic fertilizer (M, PM, NM, NPM) IFI soil fertility were 55.15,54.92,60.62,63.13. No organic fertilizer (CK, N, P, NP) soil fertility IFI treatment were 40.02,39.65,46.43,47.46.

【学位授予单位】：西北农林科技大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S158
，

本文编号：1413090