辣椒秸秆还土及蚯蚓对辣椒土壤的影响

为探究辣椒(Capsicum annuum L.)秸秆与蚯蚓对土壤的影响,试验设置3个处理,分别是钵中放入粉碎的辣椒秸秆40 g(秸秆组)、6条蚯蚓(蚯蚓组)、粉碎的辣椒秸秆40 g+6条蚯蚓(混合组),每个处理4钵土壤,共计12钵。结果表明,秸秆组土壤蔗糖酶、脲酶、纤维素酶和蛋白酶活性分别是混合组的1.69、1.68、0.93、1.60倍,是蚯蚓组的1.80、2.37、0.57、1.42倍;土壤铵态氮含量蚯蚓组最高,硝态氮含量秸秆组最高,氨基酸含量秸秆组最高;秸秆组和混合组的土壤可溶碳含量分别是蚯蚓组的1.90倍和3.25倍,秸秆组和蚯蚓组微生物碳含量分别是混合组的11.20倍和3.13倍;细菌菌落数从大到小依次为蚯蚓组、秸秆组、混合组,真菌菌落数从大到小依次为秸秆组、混合组、蚯蚓组,放线菌菌落数最多的是蚯蚓组,其次是混合组,最小的是秸秆组。辣椒生物量从高到低依次为秸秆组、混合组、蚯蚓组,表明辣椒秸秆还土对辣椒的生长有促进作用。

绿肥聚垄秸秆还土培肥增产添效作用的研究

在“毕节百万亩粮食高产工程”项目区内黄壤和石灰土上进行了３个点的定位试验。１９９７年～１９９８年度试验结果表明，在施用一定量的氮、磷、钾肥的基础上，绿肥聚垄、秸秆还土和绿肥聚垄＋秸秆还土均能提高土壤有机质和氮、磷、钾养分合量，增加土壤水稳性团聚体含量，改善土壤物理特性，提高土壤肥力；能够促进作物生长发育，改善作物经济性状，提高产量，增加经济效益，各处理的多点平均粮食复合产量比对照增加２８．２～９４．８ｋｇ／６６７ｍ２，增产５．６６％～１９．０３％，平均纯收入比对照增加１７．１～９９．０元／６６７ｍ２，增产３．８％～２６．１％。其培肥增产添效作用显著。

不同作物秸秆还土对玉米及土壤肥力的影响

为了研究不同作物秸秆培肥地力的作用，进而提高旱地地力水平，对不同作物秸秆还土对玉米及土壤肥力的影响进行了试验。结果表明．不同作物秸秆还土后具有一定的增产作用，其中，玉米秸秆和烤烟秸秆还土的增产效果最显著，比CK增产24．82％～25．69％，其次是油菜秸秆和马铃薯秸秆的还土处理，比CK增产18．40％～19．44％，小麦秸秆比CK增产8．33％。不同秸秆还土能不同程度增加土壤的有机质、全氮、碱解氮，保持速效磷、速效钾的平衡，其中，烤烟秸秆增加速效钾量能力强；玉米秸秆对提高土壤有机质、增加氮素作用较强；油菜秸秆由于腐熟快，增加氮素能力最强；马铃薯秸秆和小麦秸秆相对其他秸秆培肥地力能力稍差。秸秆还土可以改善玉米的生育性状，从而促进玉米增产。

绿肥聚垄秸秆还土对玉米及土壤的影响

通过大方县绿肥聚垄秸秆还土对玉米产量及土壤肥力的影响初步研究表明 ,绿肥聚垄、秸秆还土增加了土壤有机质及养分含量 ,改善了土壤环境 ,提高了土壤肥力 ,促进作物高产、稳产。

不同秸秆还土效果的研究

用玉米、烤烟秸秆还土种玉米产量较高,增产效果较为明显。建议充分用好作物桔杆,在玉米主产区、烤烟区,尤其是玉米、烤烟轮作区可以大面积采用玉米、烤烟秸秆还土,对培肥地力,提高玉米产量方面均有一定效果。

小麦秸秆还土甘薯垄作免耕高产栽培技术初探

在麦-玉-薯耕制下,忠县新生镇农业服务中心2008-2009年度通过在甘薯栽培上采用小麦秸秆还土甘薯垄作免耕高产栽培技术试验示范,摸索出了最佳的栽培方式,2010年在全县大面积推广,平均亩产鲜薯1452kg,比常规栽植亩增288kg,增产率达24.7%,亩增效115元左右。实践证明,此项技术是一项能够取得良好生态效益和经济效益的简单适用技术,值得大面积推广。

小麦秸秆还土施用腐熟剂对玉米和红薯产量的影响

为探索秸秆腐熟剂对秸秆的腐熟效果、对土壤微生物的影响,及其对粮食作物的增产效果,特在铜梁县东城街道安全村实施小麦秸秆还土施用腐熟剂后种植玉米和红薯的试验。结果表明:(1)小麦秸秆还土施用秸秆腐熟剂对玉米增产有一定效果,对红薯增产效果显著;(2)小麦秸秆还土施用秸秆腐熟剂有明显加速秸秆腐熟的效果,土壤微生物数量增加的速度特别明显;(3)在小麦秸秆还土施用腐熟剂的基础上,加碳氮比调节剂(6kg/667m2尿素),对玉米、红薯增产效果最显著。

贵州喀斯特山区旱地绿肥聚垅秸秆还土的培肥增产效应研究

在贵州喀斯特山区黄壤和石灰土上进行定位试验 .研究结果表明 ,绿肥聚垅、秸秆还土和绿肥聚垅 +秸秆还土均能在一定程度上提高土壤有机质及养分含量 ,改善土壤物理性状 ,提高土壤肥力 ;促进作物 (特别是玉米 )生长发育 ,改善作物经济性状 ,提高产量 ,各处理的年平均粮食复合产量比对照增加36 .3～ 1 1 7.0kg/ 6 6 7m2 ,增加 5.6 8%～ 2 0 .97% .

绿肥与秸秆混合还土效果试验

为改进干秸秆还土见效慢的不足,采用田间小区试验的方法,在贵州省黔西县进行了绿肥与秸秆混合还土的效果试验。结果表明:在垄作、规范化种植的基础上绿肥与秸秆混合施用玉米增产效果明显,粗蛋白含量明显提高,土壤有机质、全量氮、磷、钾比对照土壤略有增加,土壤pH、有效磷略有增加。综合考虑,初步认为绿肥与秸秆混合施用是比单一秸秆还土更好的秸秆还土技术。

毕节地区小麦秸秆覆盖还土试验研究

通过 1999～ 2 0 0 1连续 3年的定点研究表明 :小麦秸秆覆盖还土可以提高土壤有机质含量 ,增加土壤有效养分 ,改善土壤物理性状 ,且有保墒、保温、疏松土壤等特点。小麦秸秆还土比对照未覆盖的玉米增产 ,尤以覆盖小麦秸秆 +酵素菌催腐后增产效果最优 ,比对照增产 11.7% ,差异达显著水平。

四川秸秆资源农田综合利用成效显著

四川省农业厅组织土肥科技人员,结合四川耕作制度的实际,摸索、完善、规范了五大秸秆还田实用技术,即秸秆覆盖技术、两季田固定厢沟双免耕秸秆还田技术、旱地做垄秸秆还土技术、秸秆快速腐熟技术、食用菌生产菌渣还田技术。

Effects of Straw Returning to Fields on Soils and Current Status in Anhui Province

In the research, effects of straw returning to fields on soil temperature, water, volume-weight, porosity, trace elements, and organic matters were reviewed and countermeasures were proposed to promote straw returning on basis of straw resources and present status in Anhui Province.

Mixing Alfalfa Straw and Maize Straw to Enhance Nitrogen Mineralization, Microbial Biomass and Enzyme Activity: A Laboratory Study

The quality of straw affects N release after straw retention. As straw with high C： N ratio could result in N immobilization, additional N is needed to compensate N demand of crops. However, more and more N fertilizers have been applied to the soil to improve crop yields in China, which not only increases production cost but also reduces soil quality. Therefore, reasonable application of N fertilizer becomes a key problem after straw retention. This study aimed to assess the effects of applying maize straw with high quality alfalfa straw on mineral N content, microbial biomass and enzyme activity under controlled conditions. The effect of applying maize straw with alfalfa straw was compared with that of maize straw in combination with N fertilizer under the same C： N ratio （25：1）. The laboratory incubation experiment consisted of four treatments： （1） soil with no addition （CK）; （2） soil amended with maize straw （M）; （3） soil amended with alfalfa straw and maize straw with an adjusted C： N ratio of 25：1 （MM）; （4） soil amended with inorganic nitrogen fertilizer and maize straw with an adjusted C：N ratio of 25：1 （MF）. The results showed that application of maize straw leaded to an N immobilization during the 270 d of incubation. Combined application of alfalfa and maize straw and or mineral N fertilizer alleviates the N immobilization and increase soil mineral N content. Compared to MF treatment, MM treatment prolonged N availability during the incubation. MM and MF treatments increased the soil microbial biomass carbon and nitrogen contents, and soil invertase and β-glycosidase activities. There was no difference between MM and M treatment in soil urease activity. MF treatment had significantly negative influence on soil urease activity compared with M treatment. The amount of added N significantly affected mineral N content, soil microbial biomass and enzyme activity. The mixture of alfalfa straw and maize straw sustains higher level of mineral N content, microbial biomass and enzyme activity as it had high N input compared to maize straw in combination with N fertilizer. It is concluded that alfalfa straw may be a better N source than N fertilizer in alleviating N immobilization caused by maize straw retention.

Effect of Long-Term Rice Straw Return on Soil Glomalin, Carbon and Nitrogen

A long-term experiment was conducted to investigate how long-term fertilization and rice straw incorporation into soil affect soil glomalin, C and N. The combined application of chemical fertilizer and straw resulted in a significant increase in both soil easily extractable glomalin (EEG) and total glomalin (TG) concentrations, as compared with application of only chemical fertilizer or no fertilizer application. The EEG and TG concentrations of the NPKS (nitrogen, phosphorus, and potassium fertilizer application + rice straw return) plot were 4.68% and 5.67% higher than those of the CK (unfertilized control) plot, and 9.87% and 6.23% higher than those of the NPK (nitrogen, phosphorus, and potassium fertilizer applied annually) plot, respectively. Application of only chemical fertilizer did not cause a statistically significant change of soil glomalin compared with no fertilizer application. The changes of soil organic C (SOC) and total N (TN) contents demonstrated a similar trend to soil glomalin in these plots. The SOC and TN contents of NPKS plot were 15.01% and 9.18% higher than those of the CK plot, and 8.85% and 14.76% higher than those of the NPK plot, respectively. Rice straw return also enhanced the contents of microbial biomass C (MBC) and microbial biomass N (MBN) in the NPKS plot by 7.76% for MBC and 31.42% for MBN compared with the CK plot, and 12.66% for MBC and 15.07% for MBN compared with the NPK plots, respectively. Application of only chemical fertilizer, however, increased MBN concentration, but decreased MBC concentration in soil.

Effects of different long-term crop straw management practices on ammonia volatilization from subtropical calcareous agricultural soil

Ammonia(NH3)volatilized from agricultural production and its secondary aerosols contribute greatly to air pollution.Different long-term crop straw management practices may significantly affect the soil fertility and soil nitrogen cycle,however,the effect on NH3 volatilization has not been well studied.Therefore,a one-year field experiment was conducted to evaluate the effect of straw incorporation on NH3 volatilization from subtropical calcareous agricultural soil from a longterm perspective,including four treatments:synthetic fertilizer(CK);synthetic fertilizer incorporation with 100%or 50%of the previous season’s crop straw(SI1 and SI2,respectively);and synthetic fertilizer incorporation with 50%burned crop straw(SI2B).Soil NH3 volatilizations were monitored through a wheat–maize rotation year by using a dynamic chamber method.The results demonstrated that NH3 volatilization primarily occurred within 38 days and 7–10 days following nitrogen fertilization events for the wheat and maize seasons,respectively.Different crop straw management practices mainly impacted the NH3 flux of the basal fertilization rather than the topdressing fertilization;long-term crop straw incorporation effectively lowered NH3 loss(35.1%for SI1 and 16.1%for SI2 compared to CK;and the inhibiting effect increased with increasing straw amount,possibly contributed by the high straw carbon/nitrogen ratio,and enhanced microbial activity,which contributed to inorganic nitrogen immobilization and lower ammonium content in the topsoil.However,SI2B significantly increased(29.9%)the annual NH3 flux compared with SI2,indicating that long-term 100%straw incorporation could be a promising straw management practice for mitigating NH3 loss and increasing soil fertility.

Microbial Biomass Carbon Trends in Black and Red Soils Under Single Straw Application: Effect of Straw Placement, Mineral N Addition and Tillage

Quantifying trends in soil microbial biomass carbon (SMBC) undercontrasting management conditions is important in understanding thedynamics of soil organic matter (SOM) in soils and in ensuring theirsustainable use. Against such a background, a 60-day greenhousesimulation experiment was carried out to study the effects of strawplacement, mineral N source, and tillage on SMBC dynamics in twocontrasting soils, red sol (Ferrasol) and black soil (Acrisol). Thetreatments included straw addition + buried (T1); straw addition +mineral N (T2); and straw addition + tillage (T3).

Effects of Rice Straw Incorporation and Soil Pre－Flooding on the Fate of Applied （^（15）NH_4）_2SO_4－N and Growth of Rice

A pot experiment was conducted to investigate the effects of straw incorporation and soil pre-flooding on the fate of (￣(15)NH_4)_2SO_4-N and the growth of rice. Excessive application of rice straw when incorporated with (￣(15)NH_4)_2SO_4 at the C/N ratio of 40 reduced the loss of (￣(15)NH_4)_2SO_4-N and retarded the growth and development of rice significantly, while no adverse effects were observed on dry weight of panicle and the total recovery of (￣(15)NH_4)_2SO_4-N when rice straw was incorporated with (￣(15)NH_4)_2SO_4 at a C/N ratio less than 25. There were no significant effects of duration of soil pre-flooding within 6 weeks on (￣(15)NH_4)_2SO_4-Nuptake by rice and on rice growth, but, less loss of (￣(15)NH_4)_2SO_4-N was observed in the soil with a longer period of pre-flooding.