滴灌条件下土壤酸化对石灰性土壤磷锌有效性影响及其生物效应

发布时间：2018-04-30 03:08

本文选题：石灰性土壤 + 酸化　；参考：《石河子大学》2015年硕士论文

【摘要】：目的:石灰性土壤p H值较高,导致土壤养分有效性低,不利于作物对土壤储备养分资源的利用。施用酸化剂能降低土壤p H,提高养分有效性,但成本高,在实际生产中难以应用。滴灌施肥局部、高频、少量、定点施肥的特点,为酸化剂施用提供了新的手段。本试验通过研究不同类型酸性物质和酸性物质不同施用方式下土壤p H、养分有效性的变化、作物对养分吸收和产量的响应,探讨酸化剂作用下滴灌棉田磷锌的活化效果,以期为滴灌条件下提高石灰性土壤磷锌的资源利用效率提供新方法。方法:采用等量酸性物质、不同施用方式设计了酸性物质一次施用(S)和分6次施用(M),对照(CK)三个处理(微区模拟试验)。大田滴灌试验少量多次施用酸化剂设计了不施磷肥(NK),常规灌溉施肥(NPK),常规灌溉施肥配施硫酸(SA)、磷酸脲(UP)和硫酸铵+氯甲基吡啶(ASN)五个处理,各处理NPK养分用量一致(NK处理除外),部分酸化剂含有N,P养分则从其他类型肥料中扣除相同数量的同类养分。供试作物为棉花Huiyuan 710(Gossypium hirsutum L.)。微区试验通过土壤p H、磷和锌的动态变化及无机磷组分的变化,研究不同施用方式对土壤养分有效性的变化及可能的活化机制。大田试验通过土壤磷和三叶期棉花根系形态及根活等的变化研究播种期施用酸化剂对棉花的影响;酸化剂不同施用次数下不同土层深度土壤p H、有效磷和锌及棉花干物质,磷锌吸收量及产量的变化研究不同酸化剂对滴灌棉田磷锌的活化效果。结果:1.在与大田条件基本一致的模拟滴灌条件下,少量多次施用酸化剂(M)相比单次施用(S)显著降低局部土壤p H,土壤p H降低对应土壤有效磷含量的增加,对有效锌含量的增加表现不明显。各处理土壤p H降低量与土壤有效磷含量的增加量呈极显著正相关(R2=0.6334**),表明提高土壤中磷的有效性主要是通过酸溶作用。对土壤无机磷组分的分析发现少量多次施用酸化剂显著提高土壤中Water-P、Olsen-P与Ca2-P的含量,Ca2-P与Olsen-P、Water-P含量存在极显著正相关关系,相关系数分别为0.901和0.725,表明Ca2-P是试验土壤有效磷的主要磷源供给。2.播种期配施酸化剂显著降低了局部土壤p H,SA、UP和ASN处理降幅分别为0.19、0.14和0.16个单位;酸化处理局部土壤有效磷含量显著提高,SA、UP和ASN增幅分别为7.98、6.66和6.58 mg·kg-1,表明播种期施用酸化剂通过降低局部土壤p H提高了土壤中磷的有效性。三叶期棉花根系活力,各根系形态指标(根长,表面积,体积,根长密度)显著高于NPK处理,根平均直径有减小趋势。3.滴灌施肥条件下,随酸化剂施用次数增加,酸化效果得到强化,显著降低局部土壤0-10和10-20 cm土层深度p H,SA、UP和ASN最大降幅分别为0.20、0.24和0.32个单位,对应有效磷的显著增加,最大增幅分别为5.44,6.56、6.97 mg·kg-1,其中磷酸脲和硫酸铵效果较好;而在20-40 cm各处理p H变化不显著,但酸化剂处理有效磷和锌含量显著增加。表明滴灌条件下酸化剂施用具有一定的累积效应。4.酸化剂的施用显著促进了棉花干物质积累量、磷和锌吸收量,收获时SA、UP和ASN处理磷和锌的吸收量分别比NPK处理增加21.1%、18.8%、28.0%,130.82、87.09、142.10 g·hm-2;在等养分用量下,配施酸化剂处理棉花籽棉增产12-16%,其中ASN增产幅度最大;磷肥农学利用率(AEP)、表观利用率(REP)和偏生产力(PFPP)显著高于常规施肥,干物质生产效率(DMPEP)和生理利用率(PEP)降低。结论:1.施用化学酸性物质可降低石灰性土壤p H和提高土壤磷的有效性,Ca2-P是化学酸化剂活化石灰性土壤磷的主要给源,其活化机制可能是酸溶作用抑制Ca2-P向难溶态磷酸盐的转化。2.播种期配施酸化剂通过降低土壤p H,提高磷有效性,促进了三叶期棉花根系的生长,利于根系吸收养分和抵御出苗期低温,为植株后续生长奠定基础。3.在滴灌条件下,少量多次施用酸化剂能降低近根区0-20 cm土层深度土壤的p H。通过酸溶作用显著提高了近根区0-40 cm土层深度磷的有效性,促进植株对磷的吸收。土壤锌有效性的影响虽在各土层表现不一致,但促进了植株的吸收。4.在相同养分用量投入和管理水平下,滴灌下少量多次局部配施酸化剂棉花产量和磷肥利用效率显著高于常规滴灌施肥。滴灌下少量多次施用酸化剂是实现石灰性土壤上磷肥高效利用的一种有效途径。5.在三种酸化剂中,硫酸铵表现出了最强的酸化作用。
[Abstract]:Objective: the high P H value in calcareous soil leads to low soil nutrient availability and is not conducive to the utilization of soil reserve nutrient resources. Application of acidifier can reduce soil P H and improve nutrient availability, but it is difficult to apply in practical production. Drip irrigation is applied to local, high frequency, small amount, fixed fertilization and application of acidifier. In this experiment, we studied the changes in soil P H, nutrient availability and the response of crop to nutrient absorption and yield under different types of acid and acid application in different types of acid and acidic substances, and discussed the activation effect of phosphorus and zinc on the drip irrigation cotton field under the action of acidifying agent in order to improve the utilization efficiency of phosphorus and zinc in the calcareous soil under drip irrigation. A new method was provided. Methods: the acid substance was used in the same amount of acid (S) and 6 times of application (M), and three treatments (CK) were used as control (microarea simulation test). A small amount of acidifying agents were used in the drip irrigation test in the field. The phosphorus fertilizer was designed without NK, the conventional irrigation and fertilization (NPK), the routine irrigation and fertilization and the application of sulphuric acid (SA). Five treatments of urea phosphate (UP) and ammonium sulfate + chloromethyl pyridine (ASN) were treated with the same amount of nutrients (except for NK treatment). The partial acidifying agent contained N, and the P nutrient was deducted from the same amount of similar nutrients from other types of fertilizer. The test crops were cotton Huiyuan 710 (Gossypium hirsutum L.). The dynamics of soil P H, phosphorus and zinc were dynamic in the microzone test. Changes in soil nutrient availability and possible activation mechanism of soil nutrients were studied by different application methods. The effect of acidifying agent on cotton in sowing period was studied by soil phosphorus and cotton root form and root activity in the soil of soil phosphorus and three leaf stage; P H, effective phosphorus and zinc and cotton dry matter, phosphorus and zinc absorption and yield changes to study the effects of different acidifying agents on the activation of phosphorus and zinc in drip irrigated cotton fields. 1. under the simulated drip irrigation conditions, a small amount of acidifying agents (M) significantly reduced local soil P H compared with single application (S), and soil P H decreased to the corresponding soil. The increase of effective phosphorus content was not obvious to the increase of the content of effective zinc. The decrease of P H in soil was very significant positive correlation with the increase of soil effective phosphorus content (R2=0.6334**). It showed that the availability of phosphorus in the soil was mainly through acid dissolution. The content of Water-P, Olsen-P and Ca2-P in soil, Ca2-P and Olsen-P, Water-P content have a very significant positive correlation, the correlation coefficients are 0.901 and 0.725 respectively, indicating that Ca2-P is the main source of available phosphorus in the test soil to supply.2. sowing date with acidification agent, which significantly reduces the P H, SA, UP and decreasing amplitude of.2. 14 and 0.16 units, the content of effective phosphorus in the local soil improved significantly, the increase of SA, UP and ASN was 7.98,6.66 and 6.58 mg. Kg-1 respectively, indicating that the application of acidification agent in the sowing period improved the availability of phosphorus in the soil by reducing the local soil P H. Degree) significantly higher than NPK treatment, the average diameter of root mean decreased trend.3. drip fertilization conditions, with acidification increase, acidification effect was enhanced, significantly reduced local soil 0-10 and 10-20 cm soil depth P H, SA, UP and ASN, respectively, the maximum decline of 0.20,0.24 and 0.32 units, corresponding to the significant increase of effective phosphorus, the maximum increase, respectively For 5.44,6.56,6.97 mg kg-1, the effect of urea phosphate and ammonium sulfate is better, but the changes of P H in the treatment of 20-40 cm are not significant, but the content of effective phosphorus and zinc is significantly increased by acidifying agent. It shows that the application of acidifying agent with a certain cumulative effect.4. acidifying agent under drip irrigation shows the accumulation of dry matter in cotton, phosphorus and zinc absorption. The absorption of phosphorus and zinc at harvest SA, UP and ASN increased by 21.1%, 18.8%, 28%, 130.82,87.09142.10 G. Hm-2, respectively. Under the same amount of nutrients, the yield of cotton seed cotton was added with acidification agent to increase the yield 12-16%, and the increase in ASN yield was the greatest. The utilization ratio of phosphate fertilizer (AEP), apparent utilization ratio (REP) and partial productivity (PFPP) were significantly higher. In conventional fertilization, dry matter production efficiency (DMPEP) and physiological utilization rate (PEP) decrease. Conclusion: 1. chemical acidity can reduce the P H of calcareous soil and increase the availability of soil phosphorus. Ca2-P is the main source of chemical acidifying agent to activate calcareous soil phosphorus, and its activation mechanism may be the inhibition of Ca2-P to refractory phosphate by acid dissolution. The application of Acidifier in.2. seeding period by reducing soil P H, improving the availability of phosphorus, promoting the growth of root of cotton in the three leaf period, absorbing nutrients and resisting the low temperature of the seedling stage, laying the foundation for the following growth of the plant, under the drip irrigation condition, a small amount of acidifier can reduce the P H. in the depth of the 0-20 cm soil layer of the near root zone. The effect of excess acid solubilization significantly increased the availability of phosphorus in the 0-40 cm soil layer in the near root zone and promoted the absorption of phosphorus. The effect of soil zinc efficiency was inconsistent in the various soil layers, but it promoted the plant absorption of.4. under the same nutrient input and management level, and the yield of acidifying agent cotton and phosphate fertilizer were few times under drip irrigation. The utilization efficiency is significantly higher than that of the conventional drip irrigation. A small amount of acidifying agent under drip irrigation is an effective way to achieve high efficiency utilization of phosphate fertilizer on calcareous soil.5.. In the three acidifying agents, ammonium sulfate shows the strongest acidification effect.

【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S275.6;S153.6

【参考文献】