生物质炭土壤改良效应研究进展

生物质炭对全球碳的生物地球化学循环和缓解全球气候变化具有重要的影响,已被认为是大气CO2的重要储库。现有研究表明,施用生物质炭在进行碳固持的同时,还可以通过改善土壤理化性质、提高土壤肥力、修复土壤污染等形式对区域及全球土壤生态系统功能产生影响。本文在文献资料调研的基础上,系统论述了生物质炭的主要性质以及生物质炭用于改良土壤的研究现状,评价了生物质炭化还田技术所具有的突出优势,并提出了今后研究中需要解决的关键问题。     

生物质炭施用量对旱地酸性红壤理化性质的影响

我国南方旱地酸性红壤区,土壤酸化与干旱等问题突出。近几年生物质炭在土壤改良方面的研究应用已有较多的文献报道,但针对南方旱地酸性红壤区土壤改良方面的研究与应用相对较少。对此,本研究设置了生物质炭施加量分别为1%、2%、3%、4%及对照CK共5个处理,每个处理5次重复的室内盆栽试验;每盆一次性均匀浇洒1 L蒸馏水后在温室内自然放置,模拟干旱30 d,随后测定土壤含水量、p H、电导率与氮、磷含量。结果表明:土壤pH、电导率、有效磷含量随生物质炭施加量的增加而显著提高,NH₄⁺-N含量降低,而NO₃^–-N含量无显著影响;模拟干旱后的土壤含水量与生物质炭施加量呈二次函数曲线关系,施加低量生物质炭(1%)显著降低了土壤含水量,而高量生物质炭(4%)的施加则使土壤含水量显著提高。本研究为生物质炭在我国南方旱地酸性红壤区土壤改良方面的应用提供了试验依据。     

生物质炭基肥缓释性能及对土壤改良的研究进展

生物质炭基肥是以生物质炭为基质,与有机、无机肥料配制而成的新型生态环保缓释肥料,也作为土壤改良剂应用于农业生产中,近年来受到农业与环保领域的广泛关注和研究应用.本文讨论了生物质炭基肥缓释性能机制及影响因素,生物质炭基肥的缓释性能在很大程度上取决于磷、氮、钾元素与生物质炭的结合方式.主要结合方式包括静电吸附、络合、矿化等...     

秸秆生物质炭对红壤酸度的改良作用:回顾与展望

回顾了近年来用秸秆生物质炭改良红壤酸度和钝化污染红壤中重金属等方面的研究进展,并对该领域未来的发展趋势作简要展望。     

生物质炭对茶园土壤改良及茶叶品质的影响

近年来,茶树种植过程中化肥的超量施用造成茶园土壤酸化加剧和有机质含量降低等一系列问题,进而影响到茶叶的产量和品质。生物质炭一般呈碱性,具有含碳量高、比表面积大、高度生物化学稳定性和较强的吸附性能等特性,能够增加土壤碳储量,提高土壤pH值和养分有效性,对于茶园土壤固碳、土壤改良和抑制土壤氮磷流失、改善农产品品质等方面有较大作用。针对我国茶园土壤存在的主要问题,以生物质炭的特性及生物质炭改良土壤的作用机理为研究对象,重点阐述了生物质炭在茶园酸化土壤改良、土壤氮素淋失阻控、土壤固碳增汇等方面的效应,以及生物质炭提高茶叶产量和提升茶叶品质方面的作用机理。基于以上研究,展望了生物质炭在茶园管理方面的理论研究方向,为生物质炭在农业生产中的应用和推广提供科学依据。     

生物质炭改良土壤及对作物效应的研究进展

生物质炭是作物秸秆等有机物质在限制供氧的条件下加热而成。生物质炭具有养分含量丰富、碱性和高稳定性等特点,因此可以降低土壤酸度,有效截留土壤养分,并在一定程度上促进养分吸收而提高作物产量。本文主要综述了生物质炭制备的影响因素及其施用后对土壤理化性质、作物生长发育和养分吸收等方面的影响。由于生物质炭在国内外的研究仍处于起步阶段,研究过程中所采取的方法、所用不同来源的生物质炭以及研究的具体对象等不尽相同,研究的结果显示生物质炭在某些方面的作用仍存在不同结论。目前,生物质炭的研究多集中在表面宏观现象上,对其深入的机理研究仍较欠缺,因此,需要科技工作者的进一步探索,文章最后阐述了未来对该领域研究的一些观点。     

生物质炭改良酸性土壤的电化学特性研究

设置五种有机物料（水稻秸秆、玉米秸秆、小麦秸秆、稻壳和竹子）制备的生物质炭改良酸性土壤的田间试验,以不施生物质炭为对照（CK）,运用电化学阻抗谱法研究不同生物质炭对酸性土壤电化学特性的影响。结果表明,不同处理的等效电路拓扑结构一致,但电路元器件参数存在差异;Nyquist图表现为高频区圆弧和低频区斜线的形式,各曲线与横坐标的截距对应等效电路中土壤多孔层电阻R2,圆弧半径对应电荷转移电阻R3,Bode图中不同生物质炭改良酸性土壤的阻抗模值随频率增大整体呈减小趋势。采用Z-view软件拟合出等效电路图可知,不同生物质炭改良酸性土壤对各元件参数值的影响为孔隙溶液电阻R1减小,土壤多孔层电阻R2增大和电容C1减小,电荷转移电阻R3和扩散阻抗系数W增大,以及CPE-T值减小。其中,R1的减小表示土壤水溶性盐含量和CEC的增加;R2增大和C1减小表示土壤介质体系的导电能力降低;R3、W和CPE-T值的变化表示土壤体系的转移电荷能力降低和整体稳定性的提高。拟合参数值在一定程度上揭示了改良酸化对土壤pH和可溶性盐基离子含量的影响,同时丰富了电化学阻抗谱的研究范围。     

生物质炭对旱作土壤生物性状及养分有效性的调控效应

通过盆栽试验研究了生物质炭施用对贵州中部地区旱作土壤微生物群落数量、酶活性和土壤养分有效性的影响。结果表明:对不同类型旱作土施用5%～15%(炭/土质量比)的生物质炭后,黄泥土、黄砂土中真菌、放线菌、细菌数量和硝化细菌、氨化细菌数量以及磷酸酶、过氧化氢酶、脲酶活性均表现出明显的增加,特别是黄砂土;而大泥土中放线菌、真菌数量和硝化细菌数量以及磷酸酶和过氧化氢酶活性出现较明显的提高,但氨化细菌数量及脲酶活性出现大幅度降低。此外,黄泥土、黄砂土施生物质炭后有效N、P、K、Ca、Mg、B含量表现出不同程度的增加,但土壤有效Fe、Mn、Cu、Zn含量则出现不同程度的下降;而大泥土中有效P、K、Fe、Mn、Cu、B的含量呈现不同程度的提高,但土壤有效N、Ca、Mg、Zn的含量出现不同程度的减少;其中这3类旱作土壤施炭后土壤有效Zn含量均表现出显著的下降。黄泥土、黄砂土及大泥土施用5%～15%的生物质炭后均能明显提高白菜及莴笋的产量,其中黄砂土施生物质炭的增产效果最好,其次是大泥土。不同类型旱作土壤施炭后土壤有效性养分数量变化存在较大的差别,施用生物质炭时要根据土壤特性配合使用一定比例的氮、磷、钾及适量的微量元素肥料,更有利于促进作物的生长。     

两种生物质炭对酸性紫色土腐殖质组成的影响

生物质炭的性状与原料中木质纤维含量密切相关,为探明不同原料生物质炭对土壤腐殖质组成的影响,选取玉米秸秆和紫茎泽兰分别作为纤维类和木质类原材料制备生物质炭,向酸性紫色土分别添加5%玉米秸秆生物质炭（MB）和5%紫茎泽兰生物质炭（EB）,测定90 d室内培养期间土壤胡敏酸（HA）、富里酸（FA）、胡敏素（HM）含量以及HA光学性质和元素组成变化。结果表明：MB和EB的比表面积分别为2.32 m²·g^-1和0.72 m²·g^-1,总孔体积分别为42.71 mm³·g^-1和12.59 mm³·g^-1,碳与氢元素摩尔比（C/H）分别为1.91和1.46,氧、硫之和与碳元素摩尔比[（O+S）/C]分别为0.09和0.16,玉米秸秆生物质炭的吸附能力更强、有机质成分的缩合度更大且氧化度更小。与对照（不添加生物质炭,CK）相比,培养结束后,施入生物质炭的土壤HA、FA和HM含量分别显著增加（P<0.05）65.59%~102.82%、85.87%~118.54%和137.25%~161.23%,MB处理对这3种腐殖质含量的增加效应较EB处理更明显。培养结束时添加生物质炭的土壤HA/土壤有机碳（SOC）降低13.53%~27.06%,FA/SOC降低6.81%~18.03%,其中EB处理的降低效应达显著水平;HM/SOC则增加4.58%~11.40%,其中MB处理的增加效应达显著水平。添加生物质炭的土壤HA色调系数（ΔlgK）增加2.40%~5.60%,HA的缩合度（C/H）降低3.51%~11.81%,（O+S）/C增加1.51%~8.74%。总体来看,施入生物质炭均能相对增加腐殖质各组分含量,降低C/H,提高HA的氧化度[（O+S）/C],且纤维类原料（玉米秸秆）生物质炭的效果更明显。纤维类原料（玉米秸秆）生物质炭显著提高了稳定性较高的土壤胡敏素碳比例（HM/SOC）,但降低了土壤HA的稳定性[HA的C/H降低,（O+S）/C增加];木质类原料（紫茎泽兰）生物质炭显著降低土壤胡敏酸碳比例（HA/SOC）和富里酸碳比例（FA/SOC）,对HM/SOC增加效益不显著,反之提高了土壤易分解有机碳比例。     

制炭温度对玉米和小麦生物质炭理化性质的影响

通过缓慢高温裂解方式生产不同温度的小麦和玉米生物质炭,并对其性质进行分析.结果显示,生物质炭性质受裂解温度和生物质种类的影响而表现出差异.当裂解温度从300℃升高到500℃时,小麦生物质炭产率从44.3％降低到38.4％,其生物质炭碳含量从617.9 g/kg升高到674.0 g/kg;玉米生物质炭产率从42.8％(300℃)降低到29.7％(500℃),其生物质炭碳含量从574.8 g/kg(300℃)升高到651.1 g/kg(500℃).生物质炭pH、灰分含量、全磷含量等也随制炭温度升高而升高,小麦生物质炭pH从7.59(300℃)上升到10.51(500℃),灰分含量从186.1 g/kg(300℃)升高到268.2 g/kg(500℃),全磷含量从0.70 g/kg(300℃)升高到1.10 g/kg(500℃);玉米生物质炭pH从9.35(300℃)升高到10.12(500℃),全磷含量从2.34 g/kg(300℃)升高到4.37 g/kg(500℃).说明制炭温度和生物质种类对生物质炭理化性质具有决定性作用.     

三种植物物料对两种茶园土壤酸度的改良效果

用室内培养实验研究了稻草、花生秸秆和紫云英在 5、10 和 20 g/kg 的加入量水平下对茶园黄棕壤和茶园红壤酸度的改良效果.结果表明:除了黄棕壤加入紫云英处理会降低土壤的 pH 外,其余所有加入植物物料的处理均使土壤 pH 有不同程度的增加,使土壤交换性酸和交换性Al的数量减小,使土壤交换性盐基阳离子和盐基饱和度增加.有机物料对土壤酸度的改良效果与有机物料灰化碱和N含量有关,灰化碱和有机N的矿化使土壤 pH 升高,NH4+-N的硝化使土壤 pH 降低.3种植物物料中花生秸秆对土壤酸度的改良效果优于紫云英和稻草.加入植物物料使红壤中有毒形态Al的浓度显著减小,说明植物物料能够缓解红壤中Al对植物的毒害.     

Effects of biochars and hydrochars produced from lignocellulosic and animal manure on fertility of a Mollisol and Entisol

Biochar and hydrochars (HC) are emerging soil fertility amendments; however, their ability to improve fertility levels in soils possessing vastly different pedogenic characteristics has not been well investigated. In this study, several plant and manure biochars and two blended HC applied at 3.84 g/kg (ca.10 t/ha) were incubated in pots containing a highly fertile‐Mollisol (Waukegan series; Sandy‐skeletal, mixed, superactive, mesic Typic Hapludoll) and an infertile Entisol (Margate series; Siliceous, hyperthermic, Mollic Psammaquent). During the 124–125 day laboratory incubations, pots were leached four times with deionized H₂O with the leachates analysed for the concentrations of dissolved phosphorus (DP) and potassium (DK). After the incubations, both soils were analysed for fertility characteristics (i.e. pH, cation‐exchange capacity (CEC), and extractable P and K). In both soils after biochar additions, there were mixed pH and CEC responses. Both the Mollisol and Entisol treated with swine solid biochar had greater plant extractable P and K contents, which was reflective of the elevated P and K contents in the swine solid biochar. However, most biochars and HC additions to the Mollisol and Entisol had minimal impact on soil fertility characteristics indicating a low direct fertilization potential. These nutrient contents could be altered through feedstock blending to target a particular fertilizer requirement.     

炭化生活污水污泥对酸化红壤的改良效果

从南京市、马鞍山市和丹阳市的3个污水处理厂采集污泥,在500℃下热解制备炭化污泥,测定了污泥和炭化污泥的性质和重金属含量,研究了污泥和炭化污泥对酸性红壤改良效果,并探讨了炭化污泥中重金属的环境风险。结果表明,污泥和炭化污泥中含有一定量的碱,添加炭化污泥可提高红壤的p H和交换性钙、镁和钾含量,降低土壤交换性铝和交换性H+含量。但污泥中大量铵态氮的硝化作用释放质子,抵消了污泥对红壤酸度的改良作用。添加污泥和炭化污泥提高了土壤有机碳、有效磷和速效钾的含量,提高了土壤肥力。污泥炭化后重金属含量有所增加,但大部分重金属的有效态含量下降,说明热解过程可以降低部分有毒重金属的活性。与对照相比,添加炭化污泥会增加土壤中部分重金属有效态含量,特别是有效态锌含量显著增加,因此炭化污泥农业利用存在一定的环境风险。建议将炭化污泥用于酸化的森林红壤的改良。     

The amelioration effects of low temperature biochar generated from nine crop residues on an acidic Ultisol

Biochar was prepared using a low temperature pyrolysis method from nine plant materials including non‐leguminous straw from canola, wheat, corn, rice and rice hull and leguminous straw from soybean, peanut, faba bean and mung bean. Soil pH increased during incubation of the soil with all nine biochar samples added at 10 g/kg. The biochar from legume materials resulted in greater increases in soil pH than from non‐legume materials. The addition of biochar also increased exchangeable base cations, effective cation exchange capacity, and base saturation, whereas soil exchangeable Al and exchangeable acidity decreased as expected. The liming effects of the biochar samples on soil acidity correlated with alkalinity with a close linear correlation between soil pH and biochar alkalinity (R² = 0.95). Therefore, biochar alkalinity is a key factor in controlling the liming effect on acid soils. The incorporation of biochar from crop residues, especially from leguminous plants, can both correct soil acidity and improve soil fertility.     

Effect of crop residue biochar on soil acidity amelioration in strongly acidic tea garden soils

Strongly acidic soil (e.g. pH < 5.0) is detrimental to tea productivity and quality. Wheat, rice and peanut biochar produced at low temperature (max 300 °C) and differing in alkalinity content were incorporated into Xuan‐cheng (Ultisol; initial pH_{soil/water = 1/2.5} 4.12) and Ying‐tan soil (Ultisol; initial pH _{soil/water = 1/2.5} 4.75) at 10 and 20 g/kg (w/w) to quantify their liming effect and evaluate their effectiveness for acidity amelioration of tea garden soils. After a 65‐day incubation at 25 °C, biochar application significantly (P < 0.05) increased soil pH and exchangeable cations and reduced Al saturation of both tea soils. Association of H⁺ ions with biochar and decarboxylation processes was likely to be the main factor neutralizing soil acidity. Further, biochar application reduced acidity production from the N cycle. Significant (P < 0.05) increases in exchangeable cations and reductions in exchangeable acidity and Al saturation were observed as the rate of biochar increased, but there were no further effects on soil pH. The lack of change in soil pH at the higher biochar rate may be due to the displacement of exchangeable acidity and the high buffering capacity of biochar, thereby retarding a further liming effect. Hence, a significant linear correlation between reduced exchangeable acidity and alkalinity balance was found in biochar‐amended soils (P < 0.05). Low‐temperature biochar of crop residues is suggested as a potential amendment to ameliorate acidic tea garden soils.     

农业废弃物制备的生物质炭对红壤酸度和油菜产量的影响

利用自行研制的生物质炭化炉在田间条件下制备花生秸秆炭和油菜秸秆炭,采集秸秆气化站产生的稻壳炭,研究了这3种生物质炭对酸性土壤的改良效果和对油菜产量的影响。结果表明:施用稻壳炭、花生秸秆炭和油菜秸秆炭均可提高土壤p H,降低土壤交换性酸含量,效果随施用量的增加而增强。生物质炭对酸性土壤的改良效果主要决定于其本身的含碱量,施用花生秸秆炭和油菜秸秆炭显著增加土壤交换性盐基阳离子、有效磷、有效阳离子交换量和盐基饱和度,并提高油菜籽产量。田间条件下施用花生秸秆炭和油菜秸秆炭3年后土壤p H仍明显高于对照处理,说明生物质炭对土壤酸度的改良具有持续性。因此,花生秸秆炭和油菜秸秆炭是优良的酸性土壤改良剂。     

减氮条件下生物质炭施用对珠三角地区生菜产量、品质及土壤性质的影响

生物质炭(biochar,BC)施用具有改良土壤、提高作物产量等效应。本文探究了生菜产量、品质和土壤性质等对化肥氮(N)减施和生物质炭施用1年后的响应，以期为珠三角地区露地蔬菜生产中化肥合理减量和生物质炭科学施用提供依据。通过在佛山市三水区开展田间小区试验，观测了常规施氮(N100%)、减氮20%(N80%)、减氮40%(N60%)、减氮40%+生物质炭10 t/hm²(N60%+BC10)和减氮40%+生物质炭20 t/hm²(N60%+BC20)处理下生菜产量、品质、叶片SPAD值及土壤养分等指标的变化。结果表明：(1)较N100%处理，N60%处理生菜产量显著降低13.5%。减氮40%条件下，配施10～20 t/hm²生物质炭可提高生菜产量9.5%～22.7%，与N100%处理产量相当，说明生物质炭施用对生菜产量具有显著提升效果。(2)氮肥减量和生物质炭施用对生菜单株鲜重、直径和水分含量等均无显著影响，而对叶片SPAD值在不同生育期有不同影响。减氮条件下施用生物质炭处理生菜的氮和磷吸收量提高，是其增产机理之一。(3...     

Localisation of nitrate in the rhizosphere of biochar-amended soils

A wheat seedling rhizobox approach was used to differentiate between the rhizosphere and non-rhizosphere (bulk) soil amended with low and high rates of biochar (20 and 60 t ha⁻¹ vs. control). Nitrate (NO₃⁻) was added as the main nitrogen (N) source because emerging biochar research points to reduced NO₃⁻ loss through leaching and gaseous loss as nitrous oxide. The rhizosphere under the different treatments were distinct (P = 0.021), with greater soil-NO₃⁻ and biochar-NO₃⁻ contents in the high biochar treatment. Biochar addition increased wheat root length ratio (P = 0.053) and lowered root N uptake (P = 0.017), yet plant biomass and N content were similar between treatments. The results indicate localisation of NO₃⁻ within the rhizosphere of biochar-amended soils which has implications for NO₃⁻ loss and improved nitrogen use efficiency.     

农业废弃物及其制备的生物质炭对酸性土壤的改良作用

The liming potential of some crop residues and their biochars on an acid Ultisol was investigated using incubation experiments. Rice hulls showed greater liming potential than rice hull biochar, while soybean and pea straws had less liming potential than their biochars. Due to their higher alkalinity, biochars from legume materials increased soil pH much compared to biochars from non-legume materials. The alkalinity of biochars was a key factor aflecting their liming potential, and the greater alkalinity of biochars led to greater reductions in soil acidity. The incorporation of biochars decreased soil exchangeable acidity and increased soil exchangeable base cations and base saturation, thus improving soil fertility.     

湖南省几种稻田土壤微生物区系的研究

对湖南省3个国家水稻工程基地的7种水稻土微生物区系的分析结果表明,7种水稻土中3类微生物总数依次为黄沙泥>紫沙泥>河沙泥>紫泥田>红黄泥>潮沙泥>黄泥田,特殊生理群的微生物数量也以河沙泥和紫沙泥等通气性好、质地好的土壤中最多,而黄泥田和红黄泥等紧实土壤中微生物数量较少。农业生产中要因土壤类型采取相应的农业技术措施。