發(fā)布時(shí)間：2018-04-08 13:27

  本文選題：水稻土　切入點(diǎn)：~(15)N同位素　出處：《浙江大學(xué)》2017年碩士論文

【摘要】：硝化作用是土壤氮循環(huán)過程中的關(guān)鍵過程,不同磷源輸入將對(duì)土壤氮循環(huán)產(chǎn)生多方面的影響。本文以兩種典型酸性稻田土壤S_1與S_2為研究對(duì)象,利用~(15)N穩(wěn)定同位素示蹤技術(shù)與乙炔抑制技術(shù)進(jìn)行實(shí)驗(yàn)室培育實(shí)驗(yàn),考察施加4個(gè)濃度梯度處理:不施肥處理(M0,0g/kg)、低施用量處理(Low,3.1g/kg)、中施用量處理(Medium,6.2 g/kg)、高施用量處理(High,12.4 g/kg)的常見磷源(無機(jī)磷源、有機(jī)磷源與糞源生物炭)對(duì)土壤的理化性質(zhì)、N_2O釋放與自養(yǎng)/異養(yǎng)硝化過程的影響。本論文的主要研究結(jié)果如下:(1)不同磷源施加后,土壤NH_4~+-N與NO_3~-N濃度發(fā)生變化。當(dāng)自養(yǎng)硝化過程未被抑制時(shí),土壤NH_4~+-N濃度在S_1與S_2中隨無機(jī)磷源、糞源生物炭磷源施加量的增加而降低,隨有機(jī)磷源施加量的增加而升高。施加無機(jī)磷源后S_1土壤NH_4~+-N平均濃度由施加量由低到高分別為13.51、12.38與11.13 mg/kg;在S_2土壤中,則分別為12.83、11.12與10.06mg/kg。施加生物炭后,其濃度在S,與S_2土壤中分別為13.51、12.38、11.13與12.83、11.12、10.06mg/kg。施加有機(jī)磷源后,土壤NH_4~+-N濃度在S_1中隨施加量增加分別較空白組增加了4.25、8.45與11.32mg/kg,在S_2中則分別增加了5.51、10.00與13.39mg/kg;而土壤NO_3~--N濃度在S,與S_2中隨三種磷源的施加量增加而增加。施加無機(jī)磷源后S_1土壤NO_3~--N平均濃度由施加量由低到高分別為13.40、14.64與15.44mg/kg;在S_2土壤中,則分別為15.48、16.49與19.65mg/kg。施加有機(jī)磷源后,土壤NO_3~--N濃度在S,中隨施加量增加分別為16.03、17.62與19.84mg/kg;在S_2中則分別為16.78、17.99與20.09 mg/kg。施加生物炭后,其濃度在S,與S_2土壤中分別為15.01、16.03、17.29與115.87、16.91、17.81 mg/kg。當(dāng)自養(yǎng)硝化過程被抑制時(shí),磷源種類與施加量對(duì)土壤NH_4~+-N濃度均無顯著影響;土壤NO_3~--N濃度在S,與S_2中隨三種磷源的施加量增加無明顯變化。土壤總氮濃度(Total-N)濃度在施加無機(jī)磷源后在兩種土壤中均無變化;隨有機(jī)磷源施加量的增加而增加,在S_1與S_2中分別平均增加了1.62與1.92 g/kg;與生物炭的施加僅較小程度增加,在S_1與S_2中分別平均增加了0.03與0.01 g/kg;土壤C/N比值在施加無機(jī)磷源與生物炭后呈現(xiàn)上升趨勢(shì)施加無機(jī)磷源后其值在S,與S_2中分別平均增加了1.11與0.128;施加生物炭后其對(duì)應(yīng)值則為9.04與3.61;施加有機(jī)肥后則較空白組降低,在S_1與S_2中分別降低了4.02與8.18;三種磷源施加后兩種土壤Total-P與Olsen-P均增加。(2)施加無機(jī)磷源與有機(jī)磷源均促進(jìn)兩種土壤N_2O、CO_2排放。施加無機(jī)磷源后,在S_1與S_2中N_2O釋放通量分別較空白組高出1.72與2.51mg/m~2h;在S_1與S_2中CO_2釋放通量分別較空白組高出58.07與75.04 mg/m~2h。施加有機(jī)磷源后,N_2O釋放通量對(duì)應(yīng)增加了2.25與2.72mg/m~2h;CO_2釋放通量分別較空白組增加了132.91與198.46 mg/m~2h。而糞源生物炭抑制土壤N_2O、CO_2排放,施加糞源生物炭后,在S_1與S_2中N_2O釋放通量分別較空白組降低0.09與0.138 mg/m~2h;CO_2釋放通量對(duì)應(yīng)降低14.105與13.58 CO_2 mg/m~2h。高施加量無機(jī)磷源促進(jìn)土壤NH3釋放,在S_1與S_2中最高施加量的無機(jī)磷源實(shí)驗(yàn)組中NH3釋放通量較空白組分別高出0.10與0.55 mg/m~2h;有機(jī)磷肥施加促進(jìn)土壤NH3釋放,在S_1與S_2中其平均值較空白組分別高出0.58與0.80 mg/m~2h;生物炭對(duì)土壤NH3釋放的促進(jìn)作用不如有機(jī)磷源顯著,其值在S,與S_2中分別高出0.42與0.55 mg/m~2h。(3)自養(yǎng)硝化反應(yīng)為本研究所涉及的酸性稻田土壤中NO_3~--N產(chǎn)生的主要途徑,而異養(yǎng)硝化貢獻(xiàn)率僅為2%左右。土壤S_1與S_2中總硝化率差異明顯,在土壤S_1與S_2中分別為25.394與35.233 mg kg~(-1)d~(-1);三種磷源施加對(duì)土壤S_1總硝化率的影響大于S_2。三種磷源施加后土壤總硝化速率增加,而有機(jī)磷源對(duì)于土壤總硝化速率促進(jìn)效果最大,在S,與S_2其平均值為49.66與59.26其;次為無機(jī)磷源與生物炭,其值對(duì)應(yīng)分別為42.80、41.70與42.52、45.65 mg kg~(-1)d~(-1)。三種磷源的施加均促進(jìn)土壤自養(yǎng)硝化過程。磷源類影響土壤異養(yǎng)硝化速率,生物炭提高異養(yǎng)硝化速率,施加生物炭后S_1與S_2異養(yǎng)硝化速率為0.63與0.62 mg kg~(-1)d~(-1);其次為有機(jī)磷源,其值對(duì)應(yīng)為0.46與0.53 mg kg~(-1)d~(-1)。磷源種類對(duì)土壤異養(yǎng)硝化貢獻(xiàn)率不同,無機(jī)磷源與有機(jī)磷源對(duì)土壤異養(yǎng)硝化貢獻(xiàn)率無影響,而施加生物炭后土壤異養(yǎng)硝化貢獻(xiàn)率則較空白組升高,在S_1與S_2中增量分別為0.20與0.23。
[Abstract]:Nitrification is the key process of soil nitrogen cycle in the process of different phosphorus input will have a great influence on the soil nitrogen cycle. In this paper, two kinds of typical acidic paddy soil S_1 and S_2 as the research object, using ~ (15) N stable isotope tracer technique and acetylene inhibition technique in laboratory experiment, applied study 4 concentration gradient: no fertilization (M0,0g/kg), low dosage treatment (Low, 3.1g/kg), in the fertilization treatments (Medium, 6.2 g/kg), high dosage treatment (High, 12.4 g/kg) of the common source of phosphorus (sources of inorganic phosphorus, organic phosphorus and manure derived biochar) in science chemical properties of soil, effects of N_2O and autotrophic / heterotrophic nitrification release process. The main results are as follows: (1) after applying different phosphorus sources, soil NH_4~+-N and NO_3~-N concentration changes. When autotrophic nitrification process has not been inhibited, the soil NH_4~+-N concentration in S_1 and S_2 with Inorganic phosphorus sources, increasing manure derived biochar applied phosphorus source decreases, with the increase of organic phosphorus amount increased. Applying inorganic phosphorus source after S_1 soil NH_4~+-N average concentration by applying amount from low to high were 13.51,12.38 and 11.13 mg/kg; in S_2 soil, respectively 12.83,11.12 and 10.06mg/kg. applied biochar, the concentration of S in soil and S_2, respectively 13.51,12.38,11.13 and 12.83,11.12,10.06mg/kg. applied organic phosphorus source, soil NH_4~+-N concentration in S_1 with the amount of increase were increased compared with the normal group of 4.25,8.45 and 11.32mg/kg in S_2 were increased by 5.51,10.00 and 13.39mg/kg; and the soil NO_3~--N concentration in S, increased with the increase in applied amount with three kinds of phosphorus sources in S_2. The application of inorganic phosphorus source after S_1 soil NO_3~--N average concentration by applying amount from low to high were 13.40,14.64 and 15.44mg/kg; in S_2 soil, while Don't 15.48,16.49 and 19.65mg/kg. applied organic phosphorus source, soil NO_3~--N concentration in S, with the amount of increase were 16.03,17.62 and 19.84mg/kg respectively; in S_2 16.78,17.99 and 20.09 mg/kg. biochar, the concentration of S in soil and S_2, respectively 15.01,16.03,17.29 and 115.87,16.91,17.81 mg/kg. when autotrophic nitrification process was inhibited when the source of phosphorus species and quantity had no significant effect on soil NH_4~+-N concentration; soil NO_3~--N concentration in S did not change significantly with the increase in applied amount with three kinds of phosphorus S_2. Soil total nitrogen concentration (Total-N) concentration in the application of inorganic phosphorus sources in two soils showed no changes with increasing; the amount of organic phosphorus increased in S_1 and S_2 respectively increased by 1.62 and 1.92 g/kg; with biochar only small degree increases, in S_1 and S_2 respectively increased by an average of 0.03 and 0.01 g/kg soil; The soil C/N ratio showed a rising trend in the application of inorganic phosphorus source and biochar applied inorganic phosphorus source whose value in S, and S_2 were increased by an average of 1.11 and 0.128; biochar after the corresponding values were 9.04 and 3.61; the application of organic fertilizer was lower than those in the control group, in S_1 and S_2 reduce by 4.02 and 8.18; three kinds of phosphorus sources after applying two kinds of soil Total-P and Olsen-P were increased. (2) applied inorganic phosphorus source and organic phosphorus source could promote the two kinds of soil N_2O, CO_2 emissions. The application of inorganic phosphorus source, in S_1 and S_2 in N_2O flux respectively higher than those in control group a 1.72 and 2.51mg/m~2h; S_1 and S_2 in CO_2 flux respectively compared with the blank group was 58.07 higher and 75.04 mg/m~2h. applied organic phosphorus source, N_2O flux increased by 2.25 and the corresponding 2.72mg/m~2h; CO_2 flux were increased compared with the normal group of 132.91 and 198.46 mg/m~2h. and fecal source of biochar inhibited soil N_2 O, CO_2 emission, applying manure derived biochar, in S_1 and S_2 in N_2O flux respectively lower than those in the control group 0.09 and 0.138 mg/m~2h; CO_2 flux corresponding decrease 14.105 and 13.58 CO_2 mg/m~2h. high amount of inorganic phosphorus sources to promote soil NH3 release of inorganic phosphorus sources, the experimental group was the highest in S_1 and applied in S_2 the NH3 release flux than the blank group respectively at 0.10 and 0.55 mg/m~2h; organic fertilizer applied to promote the release of NH3 in soil, S_1 and S_2 in the average 0.58 higher than the control group respectively and 0.80 mg/m~2h; biochar significantly on soil NH3 release role as organic phosphorus source, and its value in the S. S_2 were higher than 0.42 and 0.55 mg/m~2h. (3) autotrophic nitrification reaction as the main pathway of NO_3~--N involved in the research of acidic paddy soil produced by heterotrophic nitrification, the contribution rate is only about 2%. S_1 and S_2 in the soil gross nitrification rate difference is obvious, in the soil S_1涓嶴_2涓垎鍒負(fù)25.394涓，

本文編號(hào)：1721837