不同秸秆还田方式对红壤性质及花生生长的影响

通过田间小区试验研究化肥配合不同秸秆还田方式对红壤养分、生物学特性和作物生长的影响。结果表明,与其他(NPK、NPKD1、NPKD2)处理相比,氮磷钾化肥配合秸秆直接还田(NPKJG)处理土壤碱解氮降低了7.88%~31.37%,速效磷降低了7.72%~23.81%。各处理土壤脲酶活性在花生的生长期间先降低后升高,而转化酶活性先升高后降低(除NPK处理的转化酶活性持续降低外)。氮磷钾化肥配合Fe SO4促腐秸秆堆肥还田处理(NPKD2)提高了土壤脲酶活性26.14%,而配合碱渣促腐秸秆堆肥处理(NPKD1)提高了土壤转化酶活性66.13%。氮磷钾化肥配合Fe SO4促腐秸秆堆肥处理土壤微生物生物量碳含量较高,且提高了花生各农艺性状指标和产量。     

利用秸秆堆肥过程处理猪场废水的研究

进行了以玉米秆、稻草、麦秆为载体吸收猪场废水的堆肥发酵试验，以探讨利用堆肥过程处理猪场废水的可行性。结果表明：秸秆与猪场废水联合堆肥发酵可以有效地处理利用猪场废水，秸秆吸收利用粪水的吸水比为1∶5.94～1∶6.65。秸秆吸收猪粪水堆肥的温度以及50℃、55℃以上持续时间比吸收猪粪水厌氧消化液的高。玉米秆、稻草堆肥温度以及50℃、55℃以上的持续时间高于麦秆的堆肥。以玉米秆、稻草为载体的堆肥，经历了一个pH下降的酸化过程，然后再上升至8以上；以麦秆为载体的堆肥几乎一直处于酸化过程中。堆肥过程中氮、磷、钾是一个累加的过程。以稻草为载体的堆肥，其钾的含量明显高于其余两种。秸秆吸收猪粪水的堆肥，氮、磷、钾含量高于吸收猪粪水厌氧消化液的堆肥。以猪粪水厌氧消化液或麦秆为原料的堆肥不利于腐殖酸，特别是胡敏酸的形成，而玉米秆+猪粪水、稻草+猪粪水的堆肥有利于胡敏酸的形成。结果证明采用堆肥过程处理利用猪场废水是可行的。     

污泥及其混合堆肥对番茄土壤性质和N_2O排放的影响

目前关于污泥及其生物质堆肥的土地利用过程中土壤性质变化和温室气体排放数据十分缺乏,难以满足农田土壤氮素保存和温室气体减排的需求。该研究通过在番茄种植过程中添加800 kg/hm2新鲜污泥(S-H)、400 kg/hm2新鲜污泥(S-L)、800 kg/hm2秸秆堆肥(VM-S)和800 kg/hm2猪粪堆肥(VM-M),开展土壤性质、无机氮形态、作物生长以及N2O排放特征的研究。结果表明:堆肥处理显著增加了土壤电导率(electric conductivity,EC)(P0.05),其中猪粪堆肥时土壤EC值最大。添加污泥和堆肥都使土壤p H值显著上升(P0.05),最终趋于中性,且VM-M对土壤酸化的抑制效果略优于VM-S。污泥和堆肥处理时土壤NO3--N浓度显著高于对照,且各处理组NO3--N浓度均随时间逐渐下降,NO3--N主要被番茄吸收,部分NO3--N从土壤上层淋溶至下层;NH4+大多数被氧化为NO3-,部分NH4+被植物吸收。在施入的无机氮量相等情况下,VM-M、VM-S、S-H处理组中番茄地上部分生物量分别为1 515、1 383、1 103 g/株,株高分别为56.8、54.5、51.3 cm,对番茄生长的促进效果为VM-MVM-SS-H,而S-H比S-L多施入的氮肥对番茄生长并未起到明显促进作用(P0.05)。与对照相比,污泥或生物质堆肥都显著提高了土壤N2O的排放(P0.05),各处理组N2O的排放均集中于施肥后的前20天,且土壤N2O的排放通量大小顺序为S-L(0.76 kg/(hm2·a))VM-M(0.95 kg/(hm2·a))VM-S(1.19 kg/(hm2·a))S-H(1.71 kg/(hm2·a))。因此,在进行污泥及其生物质堆肥的土地利用时,应考虑有机肥的种类及其施用量,以在提高作物产量的同时改善土壤并减少温室气体排放,在进行污泥的农田利用时可先将污泥与畜禽粪堆肥。     

Vernachlässigte Phosphor‐ und Kaliumdüngung im ökologischen Landbau senkt die biologische Stickstofffixierung bei Rotklee und den Kornertrag bei nachfolgendem Hafer

Neglected P and K fertilization in organic farming reduces N₂ fixation and grain yield in a red clover‐oat rotation N₂ fixation is the most important N source in organic farming. An insufficient P, K, and S supply to legumes may reduce their N₂ fixation capacity. Consequently, the total yield of plant production may also be reduced. This problem was studied in a pot experiment with red clover followed by oat. Soil was taken from a field where organic farming had been practiced for more than 30 years without applying any mineral fertilizers or buying additional fodder. The soil (luvisol from loess) was characterized by: pH (CaCl₂) 5.4; lactate‐soluble (CAL) P 5 mg kg^–1 and K 110 mg kg^–1. 6 kg dry soil were mixed with 400 mg P applied as (i) triplesuperphosphate (TSP), (ii) rock phosphate (RP) or (iii) compost from organic household residues (BAK). An additional treatment (iv) with TSP received 1000 mg K as K₂SO₄ (TSP+K) and an additional treatment with RP (v) received only 200 mg P (RP/2). A control treatment received no fertilizer. P application significantly improved the P nutritional status of the plants (P content) and increased the N amount in the shoots of red clover (with 400 mg P per pot by 64 % to 139 % as compared to the control) and the dry matter (DM) yield by 60 % to 130 %. No significant differences between TSP and RP were found. The application of BAK resulted in a significantly higher N yield than the application of RP and TSP. The treatment TSP+K resulted in the highest DM yield (230 %), removal of P was 343 %, of K 228 %, and of N 239 % as compared to the control plants. This indicates a synergistic effect of P, K, and S on N₂ fixation, which was also found with BAK. Oat grown after red clover increased its grain yield by 132 % (200 mg P as RP) to 165 % (400 mg P treatments). This was mainly due to a higher P uptake (up to 172 %) and a higher N uptake (up to 172 %) as compared to the control.     

Effect of Application of Coir Compost, Enriched Farm Yard Manure and an Hydrophilic Polymer on Soil Moisture Content, Growth and Yield of Rainfed Sorghum in Association with Azospirillum

Field experiment was conducted to study the effect of application of new organic manures and an hydrophilic polymer in combination with fertilizer application and Azospirillum inoculation on soil moisture content, growth and yield of rainfed sorghum. Application of enriched farm yard manure with urea mixed either 24 hours before sowing or at the time of sowing produced the highest LAI, DMP and grain yield. High soil moisture content was noticed due to incorporation of coir compost. Split application of nitrogen and Azospirillum inoculation besides increasing the LAI and DMP gave 15.2 per cent and 14.5 per cent increase in yield respectively.     

玉米芯生料栽培平菇菌株筛选研究

利用半地下式塑料菇棚,进行了平菇菌株品比、接种后处理方法和栽培方式三因素的试验.结果表明:23个平菇菌株的发菌期存在显差差异,扎孔处理的显著加快菌丝生长速度,缩短发苗期,并减少杂菌污染;菌株间子实体产量差异显著。覆土栽培倡显著提高于实体产量.通过试验筛选出了适合玉米芯栽培的高产优质平菇菌株菜平1号、莱平4号、8903和pI802.     

Incorporation of heavy metals by the mud snail,Cipangopaludina chinensis malleata Reeve,in submerged paddy soil treated with composted sewage sludge

Summary The biomass of newborn snails was higher in paddy soil without rice plants than in the soil with rice plants. There was an inverse correlation between shell width and concentratins of Zn and Cu in snail flesh. The Zn and Cu concentrations in snail flesh were extremely high compared with those in the paddy soil surrounding the snails, possibly because snails ingest sludge, one of the main components of the composts. These results suggest that this type of snail may be used to eliminate Zn and Cu from paddy soil when composted sewage sludge has been applied.     

A mini-bag technique for evaluation of fungicide effects on Trichoderma spp in mushroom compost

An in vivo technique was developed to observe colonisation of mushroom compost by Trichoderma spp. Isolates of T. harzianum (Th2), T. harzianum (Th1), T. koningii (Tk) and T. viride (Tv) were artificially introduced into compost using a mini-bag system. Wheat grains, colonised by Trichoderma spp, were placed centrally on a layer of compost at the bottom of 1-litre polythene bags which were then filled with 350 g of spawned or un-spawned compost, and partially sealed. After 14 and 21 days incubation at 27 degrees C, the bags were assessed for recovery of Trichoderma from middle and top zones using a needle stab re-isolation technique and a visual colonisation scoring system. Visible green mould contamination, similar to that observed in practice, developed within 21 days. The visual colonisation scoring was reliably related to the re-isolation success. In this evaluation, Trichoderma spp showed considerable differences in their relative abilities to colonise spawned and un-spawned compost, with Th2 isolates being consistently superior to the other isolates of Th1, Tk and Tv in colonising spawned compost. This technique was employed to evaluate the effects of fungicides on the colonisation of mushroom compost by three Trichoderma spp: Th2, Th1 and Tk, using 1-litre and 5-litre mini-bag systems. Aqueous suspensions of benomyl, carbendazim, thiabendazole, prochloraz and prochloraz+carbendazim incorporated into the compost at 50 mg litre(-1), or applied to spawn at 50 mg kg(-1), reduced the colonisation by Trichoderma spp. Prochloraz and prochloraz+carbendazim were superior to benomyl, carbendazim or thiabendazole in reducing compost colonisation by Th2, Th1 and Tk, with Th2 being the most persistent type, capable of colonising treated compost in the presence of all five fungicides. The prochloraz+carbendazim mixture, not normally used in mushroom production, was equal to or better than prochloraz alone. The incidence of green mould colonisation by Th2 was as extensive in the 5-litre compost bags as in the 1-litre bags, but colonisation by Th1 and Tk was more apparent in the 5-litre bags. The in vivo mini-bag evaluations using wheat grain Trichoderma inoculum and needle stab re-isolation procedures proved an efficient method for studying colonisation and screening for effectiveness of fungicides applied to mushroom compost or spawn.