Continuous applications of biochar to rice: Effects on grain yield and yield attributes

Biochar is considered as a beneficial soil amendment for crop production. However, limited information is available on the effects of continuous applications of biochar on rice. In this study, a fixed field experiment was conducted in the early and late rice-growing seasons from 2015 to 2017. Grain yield and yield attributes with a widely-grown rice cultivar Zhongzao 39 were compared, with and without applications of biochar in each season. The results showed that grain yield initially decreased with biochar applications in the first three seasons due to decreases in grain weight and harvest index. Although there were further relative decreases in grain weight and harvest index for rice that was supplied with biochar in the fourth to sixth seasons, grain yield was increased(by 4–10%) because of increases in sink size(spikelets per m2) and total biomass. The increased sink size in rice whose soil had been supplied with biochar in the fourth to sixth seasons was achieved by increasing panicle size(spikelets per panicle) or number of panicles, or both. Our study suggests that the positive effects of biochar application on rice yield and yield attributes depend on the duration of biochar application. Further investigations are needed to determine what are the soil and physiological processes for producing yield responses associated with ongoing applications of biochar. Also, it should be evaluated the performance of biochar application combined with other management practices, especially those can increase the grain weight and harvest index in rice production.

Crop Yield and Soil Properties in the First 3 Years After Biochar Application to a Calcareous Soil

It remains unclear whether biochar applications to calcareous soils can improve soil fertility and crop yield. A long-term field experiment was established in 2009 so as to determine the effect of biochar on crop yield and soil properties in a calcareous soil. Five treatments were： 1） straw incorporation; 2） straw incorporation with inorganic fertilizer; 3）, 4） and 5） straw incorporation with inorganic fertilizer, and biochar at 30, 60, and 90 t ha-l, respectively. The annual yield of either winter wheat or summer maize was not increased significantly following biochar application, whereas the cumulative yield over the first 4 growing seasons was significantly increased. Soil pH, measured in situ, was increased by a maximum of 0.35 units after 2 yr following biochar application. After 3 yr, soil bulk density significantly decreased while soil water holding capacity increased with adding biochar of 90 t ha^-1. Alkaline hydrolysable N decreased but exchangeable K increased due to biochar addition. Olsen-P did not change compared to the treatment without biochar. The results suggested that biochar could be used in calcareous soils without yield loss or significant impacts on nutrient availability.

Effect of biochar on grain yield and leaf photosynthetic physiology of soybean cultivars with different phosphorus efficiencies

This study was conducted with two soybean cultivars, Liaodou 13 (L13, phosphorus (P)-efficient) and Tiefeng 3 (T3, P-inefficient), to investigate the effects of biochar on soybean yield and photosynthetic physiological parameters, at four biochar application rates (0, 1, 5, and 10%, w/w), and two fertilization treatments (0 and 150 kg ha–1). Grain yield, plant biomass, P accumulation, leaf net photosynthetic rate (Pn), chlorophyll index (Chl), nitrogen balance index (NBI), sucrose phosphate synthase (SPS), and sucrose synthase (SS) activities, soluble sugar, sucrose and starch contents, and leaf area duration (LAD) were measured. Biochar had positive effects on Pn, Chl, NBI, SPS, and SS activities, and leaf soluble sugar, sucrose, and starch contents of both genotypes, these effects increased with biochar application rate. L13 benefited more efficiently from biochar than T3 did, as the grain yield of L13 significantly increased by 31.0 and 51.0%, at 5 and 10% biochar, respectively, while that of T3 increased by 40.4 at 10% biochar application rate, as compared with controls. The combined application of biochar and fertilizer boosted the positive effects described, but no difference was found for grain yield in L13 among biochar application rates, while grain yield of T3 continually increased with biochar rate, among which, 1% biochar combined with 150 kg ha–1 fertilizer resulted in T3 yield increment of more than 23%, compared with the application of 150 kg ha–1 fertilizer alone. Altogether, our results indicated that the application of biochar enhanced carbon assimilation in soybean, resulting in increased biomass accumulation and yield. Differences in genotypic responses to biochar highlight the need to consider specific cultivars and biochar rate, when evaluating the potential responses of crops to biochar.

Effects of Biochar Based Fertilizer on Soil Nutrient Content and Maize Yield of Acidic Soil in Heilongjiang Province

Unreasonable fertilizer input and low fertilizer utilization seriously restrict the development of maize in Heilongjiang province. In this paper, the effects of biochar based fertilizer on the nutrient content of acidic soil and corn yield in Heilongjiang province were studied. The random block design was adopted, and seven treatments were set with four repetitions. The results showed that biochar based fertilizer increased the soil organic matter content in the mature stage of maize. The S1 (The biochar biobased fertilizer treatment 1 in acid soil), S2 (The biochar biobased fertilizer treatment 2 in acid soil), and S3 (The biochar biobased fertilizer treatment 3 in acid soil) treatments organic matter contents increased by 15.96%, 11.06% and 10.03% than SCK (The Acid Soil Control Check) respectively. The total nitrogen, total phosphorus, total potassium, total calcium of S1 treatment corn plants increased 16.81%, 15.34%, 31.20% and 22.96% than SCK. The S1 treatment increased the yield of corn, which was 1.94% higher than SCK. There was no significant difference between the yield of S2, S3 with SCK treatments, which achieved the effect of fertilization reducing.

Biochar as a Soil Amendment Tool: Effects on Soil Properties and Yield of Maize and Cabbage in Brong-Ahafo Region, Ghana

Ghana’s soil is continuously declining in fertility due to continuous cultivation and rapid mineralization of its soil organic matter. Previous studies have touted the potential of biochar to help improve soil properties and increase the yield of crops. This study investigated the effects of the application of biochar on physicochemical properties of soil and the yield of maize and cabbage in Ghana. The study indicated that application of biochar significantly increased soil organic matter (SOM) from 3.88% (for control) to 5.72% (for biochar application rate 20 ton/ha and 0 ton/ha of NPK). It also increased soil pH from 6.55 in (for control) to 7.30 (for biochar application rate 20 ton/ha) and 0 ton/ha of nitrogen (N), phosphorus (P) and potassium (K) which can help ameliorate the soil acidity problem of Ghanaian soils. This field study, demonstrated that addition of biochar from sawdust increased the yield (between the control (0 ton/ha of biochar, 0% of recommended dose of NPK) and 20 ton/ha, 0% recommended dose of NPK) of maize and cabbage by 6.66% and 7.57% respectively. This study concluded that application of biochar offers a great potential to improve soil quality and the yield of maize and cabbage in Ghana.

Residual Effect of Biochar on Soil Properties and Yield of Maize (<i>Zea mays L.</i>) under Different Cropping Systems

A field experiment was conducted to examine the residual influence of biochar applied previously to an established experiment at the Agriculture University Research Farm, Peshawar on soil properties and yield of maize crop during summer 2016. The experiment was established in RCB design with split plot arrangements having cropping systems (CS) in main plots and biochar (BC) in sub-plots. Cropping systems were: 1) wheat-mung bean;2) wheat-maize;3) chickpea-maize;and 4) chickpea-mung bean. During the past three seasons, each cropping system received biochar at 0, 40, 60 and 80 t&#183ha&#451 along with recommended dose of NPK in each season. For this study, maize was planted after chickpea and wheat in summer 2016. The results showed that grain yield, cobs weight and total N uptake of maize was significantly greater for chickpea-maize than for wheat-maize cropping system. Soil organic C was also significantly higher in soil under chickpea-maize than under wheat-maize cropping system. However, other yield components such as stover yield, harvest index and N concentration in grain and stover of maize and soil properties such as pH, EC and mineral N were non-significantly affected by cropping systems. With respect to residual effect of biochar grain yield of maize and bulk density of soil were maximum for treatment receiving biochar at 40 t&#183ha&#451 whereas cobs weight soil pH and mineral N were highest receiving biochar at 60 t&#183ha&#451. Moreover, N concentration in stover, N uptake and soil organic C were maximum for treatment receiving biochar at 80 t&#183ha&#451. However, stover yield, harvest index, N concentration in grain, and soil EC were non-significantly affected by biochar treatments. However interactions between CS × BC were significant for yield and yield parameters of maize and for soil properties (bulk density mineral N), while non-significant for harvest index, soil organic C, pH and EC. It was concluded that chickpea-maize cropping system performed better in terms of improving yield and yield components of maize and in improving soil properties. Application of biochar to previous crops also improved yield and yield parameters of the following maize as well as soil properties. Thus we recommend that legumes must be involved in cropping system for sustainable and higher productivity and improved soil properties. However, further studies are suggested to find out suitable dose of biochar for sustainable and economic crop productivity and soil fertility.

化肥减施下不同生物质炭对大棚辣椒生长及产量品质的影响

通过田间试验,考察化肥减施条件下两种小麦秸秆生物质炭在辣椒生产上的应用效果。结果表明,在氮磷钾总养分量减少30%以上的条件下,生物质炭1号(T1)、生物质炭2号(T2)均可明显改善土壤理化性质,提高大棚辣椒的产量与品质。与不施生物质炭(CK)相比,T1和T2处理的土壤有机质含量分别提高了15.57%和30.54%,辣椒产量分别提高了16.28%和12.66%,差异均显著;T1处理辣椒果实干物质、VC含量均最高,T2处理的可溶性糖、蛋白质含量均最高。综合对比两种生物质炭施肥处理效果,T1处理促进辣椒增产的效果较好,T2处理提升辣椒品质的效果较好。

减氮配施生物炭对北疆小麦产量品质及固碳减排的影响

为研究生物炭在北疆灌区农田应用的稳产增产及固碳减排综合潜力,探索农田氮肥优化施用途径,该研究于2021年4月—2022年7月在新疆奇台设置常规施氮(N1:300 kg/hm^(2))、氮肥减量15%(N2:255 kg/hm^(2))、氮肥减量30%(N3:210 kg/hm^(2))、单施生物炭(B:20 t/hm^(2))、常规施氮+生物炭(N1B)、氮肥减量15%+生物炭(N2B)、氮肥减量30%+生物炭(N3B)7个处理,分析两季小麦(春小麦、冬小麦)种植期间不同处理下麦田土壤有机碳含量、土壤呼吸速率、小麦品质及产量变化。结果表明,与单施常规氮肥相比,施用生物炭后土壤总有机碳(soil total organic carbon,SOC)、活性有机碳(active organic carbon,AOC)、碳库管理指数(carbon pool management index,CPMI)和小麦产量、籽粒水分及蛋白(干基)含量均呈提高趋势。综合表现以氮肥减量15%配施生物炭(N2B)处理最优,较氮肥常规单施(N1)相比,AOC、SOC均有显著提高,2 a产量分别显著提高22.12%、36.17%(P<0.05)。与常规施氮相比,氮肥减量15%配施生物炭(N2B)处理下,2022年冬小麦蛋白(干基)、面筋(湿基)、Zeleny沉降值均有提高,而2021年各处理间差异不显著(P>0.05)。同时,除单施生物炭(B)处理(2021年)和除单施生物炭(B)及减氮15%(N2)处理外(2022年),其他处理下土壤CO_(2)累积排放量较单施常规氮肥均有所升高。综上,氮肥减量15%(255 kg/hm^(2))配施20 t/hm^(2)生物炭时其农田土壤固碳减排效果及小麦产量品质综合表现较好,建议作为北疆灌区麦田氮肥优化配施生物炭的理想施肥方案。

生物炭与氮肥共施对甘蔗产量和糖分质量的影响

【目的】探求生物炭对大田新植甘蔗生长的效应,从而为甘蔗生产上应用生物炭和制定氮肥高效管理提供理论基础。【方法】试验以甘蔗品种‘GT11’和‘B8’为材料,设置低氮N 120 kg/hm^(2)和高氮N 600 kg/hm^(2)2个氮水平,生物炭C0、C10和C20 t/hm^(2)3个水平,调查测定炭氮配施对甘蔗农艺生长、氮积累量和氮利用率及产量构成因素的影响。【结果】生物炭可适当增加甘蔗出苗率、分蘖率和株高,生物炭虽对产量增加无明显效应,但能够提高甘蔗糖分0.19%~0.82%,从而使产糖量增加了1.93%~10.77%。高炭处理下甘蔗氮累积量增加了0.41%~4.74%,但对氮利用率未起到显著提高作用。【结论】生物炭对新植甘蔗的分蘖、氮累积量及糖度累积起到了一定的促进作用,但这种效应因品种而异,氮在其中的作用大于生物炭的作用。

秸秆和生物炭对紫色土坡耕地产流产沙与氮素流失的影响

[目的]探究不同添加量的秸秆和生物炭对紫色土坡耕地的具体改良效果,从而为合理防治三峡库区水土流失提供理论参考。[方法]采用人工模拟降雨的方法,以裸坡为对照,研究了紫色土中添加水稻秸秆(施用量4,7,10 t/hm^(2))和生物炭(含量13,39,65 t/hm^(2))对紫色土坡耕地产流产沙与氮素流失的影响。[结果](1)高强度降雨条件下,紫色土混掺生物炭加快了坡面产流进程,而施加碎混秸秆能延长起始产流时间、削减产流速率;(2)紫色土添加生物炭后累积产沙量较对照增加了0.64%~66.29%,而施加碎混秸秆后减少了42.58%~70.27%,且施加碎混秸秆对坡面产沙的抑制效应远强于对坡面产流的控制作用;(3)地表径流中氮素流失过程以NO-3-N为主,且TN,NO-3-N和NH+4-N的流失量和养分流失模数整体表现为生物炭处理最大,碎混秸秆处理最小。[结论]紫色土坡耕地施加碎混秸秆能促渗阻流、有效控制水土及养分流失,而短期施加生物炭可能会产生负面影响。

不同蔗叶生物炭施用量对甘蔗产量及养分吸收利用的影响

【目的】研究蔗叶源生物炭不同施用量对甘蔗产量及氮磷钾养分吸收利用的影响,以期为蔗叶生物炭在甘蔗生产中的科学施用及实现养分高效利用提供理论依据。【方法】于2021—2022年开展田间试验和15N同位素示踪桶栽试验,以桂柳05136和桂糖42为供试品种,设CK(对照,不施蔗叶生物炭)、T1(蔗叶生物炭用量2.7 t/ha)、T2(蔗叶生物炭用量5.4 t/ha)和T3(蔗叶生物炭用量10.8 t/ha)4个处理,对比分析不同蔗叶生物炭用量对甘蔗收获期蔗茎和蔗叶产量、氮磷钾养分含量和吸收累积量、氮肥吸收量及氮肥利用率的影响。【结果】与CK相比,施入不同用量的蔗叶生物炭对蔗叶产量无显著影响(P>0.05,下同),但均可不同程度提高甘蔗蔗茎产量,且随蔗叶生物炭施用量增加,蔗茎产量呈先升高后降低的变化趋势,在T2处理达最高,且差异达显著水平(P<0.05,下同)。施用蔗叶生物炭,蔗茎与蔗叶氮、磷含量及地上部氮、磷吸收累积量均无显著变化,T2处理显著提高2022年大田试验蔗叶磷吸收累积量及桶栽试验蔗茎氮、磷吸收累积量。大田试验下,施用蔗叶生物炭较CK显著提高蔗茎钾含量,2021年和2022年增幅分别为31.3%~38.2%和10.5%~29.5%。蔗茎钾含量T2处理与T1处理相当,并在2022年显著高于T3处理。但在桶栽试验下,施用蔗叶生物炭对蔗茎、蔗叶及尾梢钾含量均无显著影响。施用蔗叶生物炭提高了大田试验蔗茎及地上部钾吸收累积量,其中,蔗茎增幅18.2%~45.6%,地上部增幅13.5%~32.8%,且以T2处理最高。施用蔗叶生物炭对甘蔗氮、磷养分生理利用效率无显著影响,但大田试验的钾养分生理利用效率显著降低14.7%~23.1%(2021年)和6.0%~19.5%(2022年)。15N同位素示踪进一步表明,蔗茎的氮肥吸收量最高,占总吸收量的46.5%~54.2%,蔗叶和尾梢的氮肥吸收量相当,分别占总吸收量的23.3%~27.5%和22.6%~28.0%。施用不同用量蔗叶生物炭,蔗叶与尾梢的氮肥吸收量差异不显著。T2处理较其他处理显著提高蔗茎氮肥吸收量36.5%~37.5%及氮肥利用率18.1%~24.2%。【结论】施用不同用量蔗叶生物炭对氮、磷的吸收因不同年份有所差异,但有利于提高甘蔗产量及蔗茎对钾的吸收,5.4 t/ha生物炭用量下蔗茎产量及钾吸收量最高,且显著促进蔗茎对氮肥的吸收及提高氮肥利用率,可作为推荐的适宜施用量。

减氮配施生物炭对土壤肥力和水稻产量的补偿效应与机制

氮素是水稻生长所必需的营养元素。为了提高产量往往过量施加氮肥,这不仅导致氮肥利用率低,还破坏了土壤质量,减少氮肥施用则会导致水稻减产。为探究土壤改良剂(生物炭)能否补偿减氮带来的负面影响,本研究采用盆栽试验,设置常规施氮(氮肥施用量110 kg/hm^(2),CK)、减氮10%(C1)及减氮10%条件下配施2.5%生物炭(C2)和5%生物炭(C3)4个处理,探讨在减少氮肥使用条件下生物炭对土壤肥力及水稻产量的补偿效应及机制。结果表明:减氮10%对土壤综合肥力无显著影响,施加生物炭可有效地提高土壤肥力,且添加5%生物炭对土壤肥力的提升效果优于添加2.5%生物炭。减氮10%导致水稻产量显著降低,而生物炭施加可一定程度补偿减氮造成的减产,其中添加2.5%生物炭对水稻产量的补偿效果优于添加5%生物炭,但仍未恢复到常规施氮水平。采用结构方程探究减氮和施加生物炭条件下水稻产量的驱动因素,结果表明,减氮配施生物炭通过改变土壤pH值、全钾含量、铵态氮含量和硝态氮含量,进而直接或间接影响水稻产量,其中铵态氮含量和硝态氮含量是主要的调控因子,其不仅直接影响水稻产量,还可通过调控每穗粒数、有效穗数和千粒质量间接影响水稻产量的形成;pH值和全钾含量对水稻产量有负面效应。本研究可为东北黑土区水稻种植业化肥减量和生物炭的高效利用提供科学依据。

氮肥与生物质炭配施对春小麦生长、产量及品质的影响

为了解氮肥和生物质炭配施对北疆灌区春小麦生长、产量及品质的影响,采用随机区组试验设计,以春小麦品种新春37号为供试材料,设置3个氮肥水平[不施氮肥(N0:0 kg·hm^(-2))、常规施氮(N1:300 kg·hm^(-2))、减量施氮(N2:255 kg·hm^(-2))]和4个生物质炭水平[不施生物质炭(B0:0 kg·hm^(-2))、低量生物质炭(B1:10×10^(3)kg·hm^(-2))、中量生物质炭(B2:20×10^(3)kg·hm^(-2))、高量生物质炭(B3:30×10^(3)kg·hm^(-2))],分析了不同处理下春小麦干物质积累与转运特性、籽粒产量及品质指标的差异。结果表明,生物质炭与氮肥配施可增加春小麦单株干物质积累量,提高花前同化物转运量、转运效率和对籽粒产量的贡献率,促进籽粒灌浆和产量形成,改善加工、营养品质。对小麦生长、品质及产量指标进行综合分析,减量施氮配施中量生物质炭(N2B2)处理综合表现最好,且该处理下成熟期单株干物质积累量最高,达5.12 g·株^(-1),花前同化物转运量、转运效率和对籽粒产量的贡献率分别为0.46 g·株^(-1)、15.32%、17.41%,产量较单施氮肥(N1B0)处理提高22.12%,蛋白质(干基)含量、淀粉(湿基)含量、面筋(湿基)含量、Zeleny沉降值和硬度分别为16.59%、62.12%、31.31%、46.95 mL和63.79。综上所述,在本试验条件下,减量氮肥配施中量生物质炭(N2B2)有利于北疆灌区春小麦高产优质生产。

旱作农田覆膜和秸秆碳投入对土壤团聚特性及作物产量的影响

研究秸秆还田形式对旱作覆膜农田土壤团聚特性、有机碳含量及玉米产量的影响,为优化覆膜耕作措施,实现旱作覆膜农田可持续性生产提供理论依据。以长期定位旱作玉米覆膜农田(始于2012年)为研究对象,设置双垄沟覆膜(P)和传统平作(T),分别施加秸秆(S)和生物质炭(C),以不还田为对照(N),共形成6个处理:覆膜秸秆还田(PS)、覆膜生物质炭还田(PC)、覆膜不还田(PN)、平作秸秆还田(TS)、平作生物质炭还田(TC)和平作不还田(TN)。测定土壤团聚体组成及团聚体有机碳含量,并分析了双垄沟覆膜和不同秸秆碳投入对土壤有机碳含量、团聚体稳定性及玉米产量的影响。研究结果表明,各秸秆还田处理较不还田处理均可显著(P<0.05)改善各粒级团聚体分布及其稳定性,其中>0.25mm团聚体含量平均显著(P<0.05)提高47.32%,各双垄沟覆膜处理MWD和GMD较平作处理分别平均提高9.19%和4.15%;各还田处理可显著(P<0.05)提高0~60 cm土层土壤有机碳含量,其中PC和TC处理分别较对应PS和TS处理土壤有机碳含量提高2.60%和2.73%;各处理团聚体有机碳含量均随粒径增大而增大,秸秆碳投入可显著(P<0.05)提高各粒级团聚体有机碳含量,而双垄沟覆膜处理则降低了土壤有机碳及团聚体有机碳含量;还田方式、种植方式及土壤有机碳对玉米产量有促进作用,施加秸秆及生物质炭均能显著(P<0.05)提高旱作覆膜农田玉米产量,平均提高14.6%,而秸秆直接还田处理与生物质炭还田处理的增产效果无显著差异。综合分析,在双垄沟覆膜条件下投入秸秆碳能够明显提高土壤稳定性、土壤有机碳含量和作物产量,其中,双垄沟覆膜与生物质炭还田的耦合效应对改善农田土壤质量及地力提升有积极作用。

木醋液配施生物炭对盐碱土壤理化特性和甜菜产量及品质的影响

以甜菜品种KWS 1176为试验材料,在黑龙江省肇东市尚家镇五间村盐碱地(Na+含量为203.33 mg·kg^(-1),pH值8.92)进行小区试验。试验设4个处理,不施加木醋液(CK)、木醋液300 kg·hm^(-2)(BW1)、600 kg·hm^(-2)(BW2)和900 kg·hm^(-2)(BW3),各个处理均施用生物炭(玉米秸秆),用量为600 kg·hm^(-2)。研究表明,木醋液配施生物炭显著提高土壤比表面积(提升1.39%~4.86%)和含水率,降低土壤pH和电导率;显著提高当季土壤有机质和养分(碱解氮、有效磷)含量,播后58 d土壤有机质和养分提升效果显著,其中碱解氮含量、有效磷含量和有机质含量分别提升14.24%~26.87%、21.17%~32.09%和2.51%~41.19%。BW2处理土壤中Ca^(2+)、Mg^(2+)、SO_(4)^(2-)和Cl^(-)含量显著提高,可溶性Na^(+)和HCO_(3)^(-)含量显著降低;显著提高甜菜块根产量和品质,降低块根中钠盐含量、钾盐含量和α-氨基态氮含量,比CK处理块根产量提升5.32%~15.29%,块根含糖率提升0.31%~0.84%。综合分析,BW2对改善当季盐碱土壤理化特性及甜菜块根产量和品质效果最佳。

施加生物炭对谷子干物质积累、转运、分配和土壤理化性质的影响

谷子是我国北方重要的杂粮作物,研究表明施加生物炭显著提高谷子产量,但生物炭施用对谷子干物质积累转运及沙地土壤理化性质的影响缺乏详细研究。因此,为研究生物炭对谷子干物质积累转运及分配和土壤的影响,以“榆谷抗1”为试验材料,于2021—2022年在毛乌素新开垦沙地开展田间试验,共设置1个对照组(CK,生物炭添加量0.0 t hm^(-2))和3个试验组3.0 t hm^(-2)(C1)、4.5 t hm^(-2)(C2)和6.0 t hm^(-2)(C3)。结果表明,与CK相比,新开垦沙地施加生物炭可以显著提高谷子产量和总干物质量,增长幅度分别为12.22%~53.70%和9.62%~40.62%。与CK相比,施加生物炭处理显著提高了花后0(开花期)、7、14、21、28和45 d谷子倒一叶(旗叶)至倒十三叶的叶片干重。施加生物炭提高了开花期净光合速率,花后同化物积累量、花后同化物积累量对籽粒产量的贡献率以及收获期穗的干物质分配比例,但是后三者随生物炭施用量的增加呈现略微下降的趋势。收获期茎、叶总干物质分配比例随生物炭用量增加而降低,千粒重和收获指数随生物炭施用量的增加呈现先增加后减小的趋势。相关性分析显示,谷子产量与收获期茎重(R2=0.68)、收获期地上部总重(R2=0.71)和收获期全株总重(R2=0.70)呈显著正相关。施加生物炭能有效提高土壤过氧化氢酶、脲酶和蔗糖酶的活性,并且显著提高土壤有效氮和有效磷的含量,其中C2(4.5 t hm^(-2))处理改善效果较大。综上,施加生物炭改善土壤质量,提高开花期谷子净光合速率,增加花后营养器官光合产物的积累,提高穗部干物质分配比例,最终实现谷子增产。

覆膜稻田施用炭基肥对水稻产量及氮素利用的影响

【目的】研究炭基肥及增施生物炭对覆膜水稻产量、氮素利用的影响,以期为水稻覆膜技术可持续发展应用提供理论依据。【方法】以优质粳型常规水稻品种浙禾香2号和籼粳杂交稻甬优538为材料,2021年覆膜机插种植设置CK(不施氮)、T1(施用缓释肥)和T2(施用炭基肥)处理。2022年覆膜机插种植设置CK(不施氮)、T2(施用炭基肥)、T3(炭基肥增施6t/hm^(2)生物炭)和T4(炭基肥增施12t/hm^(2)生物炭)处理,研究覆膜稻田施用炭基肥对水稻干物质积累、产量及产量构成和氮素吸收利用的影响。【结果】炭基肥促进了覆膜水稻的生长,提高了覆膜水稻产量。炭基肥显著增加水稻干物质积累量,与T1相比干物质积累显著增加5.40%~29.69%,增施生物炭与T2相比增加了覆膜水稻干物质积累量9.28%~46.91%。浙禾香2号整个生长期效果明显,甬优538在后期作用更显著。与T1相比,炭基肥能显著提高水稻产量3.84%~4.65%。增施生物炭较T2进一步提高了覆膜水稻产量7.97%~15.06%;炭基肥促进了覆膜水稻对氮素的吸收利用,提高水稻氮素利用效率。施用炭基肥显著增加覆膜水稻各生长关键时期的氮素积累量4.87%~31.68%,且氮素积累量随炭基肥增施生物炭量的增加而提高,炭基肥增施12 t/hm2生物炭(T4)氮素积累最高,较施炭基肥(T2)增加11.87%~40.59%。炭基肥降低了覆膜水稻氮素干物质生产率和氮素稻谷生产率,提高了氮肥偏生产力、氮肥农学效率和氮肥吸收利用效率。增施生物炭处理进一步提高氮素利用,减少氮素损失。【结论】覆膜稻田施用炭基肥有利于水稻干物质量和氮素积累量增加,增施生物炭能够进一步提高其效果,从而增加产量,提高氮素利用效率。浙禾香2号增产主要通过增加穗数和每穗粒数,甬优538则通过增加穗数增产,炭基肥增施12t/hm2生物炭增产效果最好。

生物炭对松嫩平原盐碱土玉米生长、养分积累及产量的影响

为了探索生物炭施用量对盐碱化土壤种植玉米的效果,进行了田间小区试验,研究了生物炭不同施用量(0,10,20,40和80 t·hm^(-2))对玉米生长、养分积累及产量的影响。结果表明,生物炭增加了花后干物质积累量,促进了籽粒灌浆速率,提升了玉米植株及籽粒对养分(C、N、P、K)的吸收,进而提高了玉米产量,改善了玉米品质。因此,在松嫩平原西部碱化玉米田上生物炭施用量40 t·hm^(-2)时玉米植株叶茎鞘养分积累最为充足,籽粒灌浆活跃期长,玉米产量最高,为最经济有效的用量。

等碳量配施玉米秸秆和生物炭对玉米生长及氮、磷、钾吸收的影响

明晰等碳量配施玉米秸秆源有机物料对玉米生长及氮、磷、钾吸收利用的影响,对于合理利用农田有机资源具有重要的指导意义。在黄土高原东部石灰性褐土上开展玉米田间试验,设置单施化肥对照(NPK)、化肥配施玉米秸秆(NPKS)、化肥配施生物炭(NPKB)3个处理,有机物料按C 4 t/hm^(2)施用,探讨等碳量配施条件下玉米拔节期农艺性状、光合参数、叶绿素荧光参数以及收获期产量构成和养分吸收特征。结果表明,NPKS处理玉米株高和叶面积较NPK处理分别增加14.8%和29.2%;NPKS和NPKB处理玉米干物质重分别增加80.8%和14.1%。与NPK处理相比,NPKS处理显著提高了玉米叶片的蒸腾速率和气孔导度以及最大光化学效率和实际光化学效率;NPKB处理显著提高了玉米叶片气孔导度以及最大光化学效率和实际光化学效率,但对净光合速率和蒸腾速率无显著影响;NPKS和NPKB处理的玉米叶片胞间CO_(2)浓度和非光化学猝灭系数呈降低趋势。与NPK处理相比,NPKS处理的玉米穗重、百粒重和产量分别增加36.4%、31.1%和45.5%;NPKB处理的玉米穗重和百粒重较NPK处理分别增加18.5%和15.2%。NPKS处理显著提高了玉米秸秆氮、磷、钾吸收量和籽粒氮、钾吸收量,NPKB处理仅显著提高了玉米籽粒氮吸收量和秸秆钾吸收量。综上所述,等碳量配施玉米秸秆源有机物料对玉米生长和养分吸收均具有促进作用;等碳量配施玉米秸秆较生物炭更有利于玉米对磷素吸收,从而促进玉米生长并提高产量。

鸟粪石基载镁生物炭对干湿交替灌溉水稻产量与品质的影响

鸟粪石(MgNH4PO_(4)·6H2O)普遍存在于镁改性生物炭对废水氮磷去除后的回收产物中,其可以作为缓释肥料使用。为探究鸟粪石基载镁生物炭(struvite-based magnesium modified biochar,MAP-BC)在农田中的应用效果以及对不同灌溉和施肥模式的适用性,该研究依托大田试验,以东研18号(粳稻)为供试材料,设置常规淹灌(ICF)、干湿交替(IAWD)2种灌溉模式,以及常规施肥(conventional fertilization,N_(1)B_(0))、常规施肥+5 t/hm^(2)MAP-BC(conventional fertilization+5 t/hm^(2)MAP-BC,N_(1)B_(1))、常规施肥+10 t/hm^(2)MAP-BC(conventional fertilization+10 t/hm^(2)MAP-BC,N_(1)B_(2))、减施氮磷肥25%+5 t/hm^(2)MAP-BC(25%less nitrogen and phosphate fertilizer+5 t/hm^(2)MAP-BC,N_(3/4)B_(1))和减施氮磷肥25%+10 t/hm^(2)MAP-BC(25%less nitrogen and phosphate fertilizer+10 t/hm^(2)MAP-BC,N_(3/4)B_(2))5种施肥模式。结果表明:与ICF相比,IAWD显著提高了乳熟期叶片叶绿素含量,并显著降低了2021年无效分蘖数(P<0.05);MAP-BC不仅能够高效弥补减施氮磷肥对水稻叶绿素含量的不利影响,还具有一定的超补偿效果;MAPBC中高纯度的鸟粪石组分通过缓释氮磷素,保障了对植株氮磷养分的长期供应。与N_(1)B_(0)相比,N_(3/4)B_(2)不仅可以满足水稻生长后期对氮磷养分的需求,还使穗部吸氮量和吸磷量分别显著增加(P<0.05)4.77%~7.06%和4.26%~12.69%;与N_(1)B_(0)相比,施加10 t/hm^(2)MAP-BC使2a的最高分蘖数和最终分蘖数分别显著增加(P<0.05)6.75%~9.64%和13.16%~16.88%;2 a试验中,在IAWD模式下,与N_(1)B_(0)相比,N_(1)B_(1)和N_(1)B_(2)的产量分别显著提高(P<0.05)了7.66%~8.43%和11.49%~12.64%,并且10 t/hm^(2)的MAP-BC可以弥补减施25%氮磷肥对产量造成的不利影响;IAWD模式下N_(3/4)B_(1)和N_(3/4)B_(2)可以显著降低消减值、垩白粒率和垩白度,显著提高崩解值,从而显著改善(P<0.05)水稻外观品质与食味值;此外,N_(1)B_(1)和N_(1)B_(2)较N_(1)B_(0)处理显著提高(P<0.05)稻米蛋白含量2.66%和5.79%,表明施用MAP-BC有助于改善稻米的营养品质。因此,在IAWD模式下减施氮磷肥25%配施10 t/hm^(2)MAP-BC可在节水条件下实现减施氮磷肥、增产、提质,从而为水稻绿色高效生产提供理论依据。