长效有机肥与烟草专用肥配施对烟草产量和品质的影响

化肥在提高农业单位面积产量的同时造成了一定的环境污染,长效有机肥的可以在一定程度上解决化肥所造成的环境压力,同时可以提高农业作物的产量和品质。本研究采用长效有机肥与烟草专用肥配施,探究不同肥料配施比例对烟草产量和品质的影响。结果表明,腐殖酸肥与烟草专用肥配合施用,能够增强烟株对气候斑病和赤星病等病害的抗病性,提高烟叶的均价、上等烟比例和上中等烟比例,促进烟叶总植物碱、氧化钾等含量的增加,降低还原糖等含量,化学成分更协调,外观质量和感官质量等有所提高,减少用工量和肥料投入,降低总投入,提高产投比,但同时表现出从移栽到团颗期的生长发育较缓慢。     

平原沙土区不同林分类型下土壤有机碳库特征及其影响因子

目的 明晰不同林分类型下土壤有机碳库特征,以期为平原沙土区土壤碳库的提高和生态恢复提供理论依据。 方法 以江苏省平原沙土区丰县16年生杨树纯林、柳树纯林、杨柳混交林3种林分类型及相邻的撂荒地（对照）为对象,测定0～20、20～40、40～60、60～80、80～100 cm等5个土壤层次有机碳及活性组分和土壤酶活性,计算土壤碳库管理指数,并对土壤有机碳库特征和环境因子进行相关性分析。 结果 （1）3种林分类型及对照各土层有机碳含量和储量范围分别为1.03～5.88 g·kg−1和3.53～17.55 t·hm−2。与对照相比,0～100 cm土层,3种林分类型土壤有机碳含量增加了45.2%～82.2%。杨树纯林0～100 cm土层有机碳储量分别是柳树纯林、杨柳混交林和对照的1.23、1.24、1.83倍。（2）与对照相比,0～100 cm土层,3种林分类型的土壤易氧化有机碳、可溶性有机碳和微生物生物量碳含量分别提高了28.6%～48.0%、6.8%～9.7%和21.6%～33.4%。3种林分类型土壤碳库管理指数显著高于100%（P<0.05）。（3）林分类型显著影响土壤蔗糖酶和多酚氧化酶活性（P<0.05）,杨柳混交林0～100 cm土层多酚氧化酶活性显著高于杨树纯林和对照（P<0.05）。（4）相关性分析表明,土壤有机碳库特征受多酚氧化酶和β-葡萄糖苷酶活性显著影响,有机碳含量和储量、易氧化有机碳含量及碳库管理指数受蔗糖酶、过氧化物酶活性显著影响,微生物生物量碳受蔗糖酶活性显著影响。冗余分析表明,土壤碳氮比和细根生物量是土壤有机碳库特征的主要影响因素。 结论 平原沙土区营造人工林提高了土壤有机碳及活性组分和有机碳库稳定性,杨树纯林提高土壤有机碳储量效果最好。     

Short term soil priming effects and the mineralisation of biochar following its incorporation to soils of different pH

The aim of this work was to determine the magnitude of the priming effect, i.e. short-term changes in the rate (negative or positive) of mineralisation of native soil organic carbon (C), following addition of biochars. The biochars were made from Miscanthus giganteus, a C4 plant, naturally enriched with ¹³C. The biochars were produced at 350 °C (biochar350) and 700 °C (biochar700) and applied with and without ryegrass as a substrate to a clay-loam soil at pH 3.7 and 7.6. A secondary aim was to determine the effect of ryegrass addition on the mineralisation of the two biochars.After 87 days, biochar350 addition caused priming effects equivalent to 250 and 319 μg CO₂-C g⁻¹ soil, in the low and high pH soil, respectively. The largest priming effects occurred at the start of the incubations. The size of the priming effect was decreased at higher biochar pyrolysis temperatures, which may be a way of controlling priming effects following biochar incorporation to soil, if desired. The priming effect was probably induced by the water soluble components of the biochar. At 87 days of incubation, 0.14% and 0.18% of biochar700 and 0.61% and 0.84% of biochar350 were mineralized in the low and high pH soil, respectively. Ryegrass addition gave an increased biochar350 mineralisation of 33% and 40%, and increased biochar700 at 137% and 70%, in the low and high pH soils, respectively. Certainly, on the basis of our results, if biochar is used to sequester carbon a priming effect may occur, increasing CO₂-C evolved from soil and decreasing soil organic C. However, this will be more than compensated for by the increased soil C caused by biochar incorporation. A similar conclusion holds for accelerated mineralisation of biochar due to incorporation of fresh labile substrates. We consider that our results are the first to unequivocally demonstrate the initiation, progress and termination of a true positive priming effect by biochar on native soil organic C.     

有机肥对石灰性土壤中锌,锰生物有效性的影响

本研究发现，有机肥猪粪，牛粪和腐熟玉米秸秆具有一定的提供锌、锰能力；石灰性土壤施有机肥能显著提高土壤锌锰的有效性；有机肥对土壤中锌、锰具有一定的活力能力；锌肥与有机肥配施可降低土壤对锌肥的固定能力，提高锌肥的利用率。     

柔毛野豌豆根瘤菌接种效果试验研究

对柔毛野豌豆进行了根瘤菌接种,使柔毛野豌豆的产草量提高了６０％－６９％,土壤多固氮３０ｋｇ／ｈｍ＾２,改良了土壤,增加了绿肥效果,为促进生态农业和生态畜牧业的有机结合开辟了新途径。     

复合有机铁对母猪繁殖性能及其抗氧化能力的影响

为研究复合有机铁对母猪繁殖性能、血液理化指标及抗氧化能力的影响,试验选用体重接近、胎次接近、预产期一致的健康“长×白”二元杂母猪30头,随机分为3组,每组10个重复,每个重复1头母猪,3个处理组分别在基础日粮中补充硫酸亚铁、甘氨酸亚铁、复合有机铁。结果显示:较硫酸亚铁组,复合有机铁组产程缩短23.57%、胎产健仔数增加14.00%、初生窝重增加14.14%(P < 0.05);母猪血红蛋白含量、红细胞数和红细胞压积分别提高19.88%、10.53%、8.33%(P < 0.05);母猪抗氧化酶活性和机体抗氧化能力提高47.33%(P < 0.05),丙二醛含量降低37.05%(P < 0.05)。综上所述,母猪日粮中额外补充复合有机铁源能提高母猪繁殖性能,改善血液理化指标,增强母猪抗氧化能力。     

Comparison of Metabolic Energy Content of Organic Cereal Grains for Chickens and Turkeys

Although there is an extensive database on the nutrient content of conventionally produced feedstuffs, there is very little published research on the nutrient content of feedstuffs that are organically grown. Industrial and organic crop production differ in both crop and soil management. There are data to suggest that these differences may result in differences in the nutrient content of organic grown feedstuffs. The purpose of this study was to determine the ME content of organically grown amaranth, buckwheat, white corn, yellow corn, and wheat samples obtained from the University of Minnesota's organic research farm. Both chickens and turkeys were used in the assays to compare the ME content for these 2 species. The TME_n content, on an as-fed basis, of amaranth, buckwheat, yellow corn, white corn, and wheat for chickens were found to be 3,146, 3,072, 3,603, 3,324, and 3,592 kcal/kg, respectively. The TME_n content of the same samples, on an as-fed basis, determined with turkeys were found to be 2,748, 2,227, 2,810, 2,757, and 2,959 kcal/kg, respectively. True ME content of the organically grown feed ingredients was found to be greater when chickens were used in the bioassay as compared with turkeys and differed significantly from published values for the same cereals grown using conventional means.