活性生物颗粒有机肥生产技术与成型设备的研究

针对我国当前有机肥生产技术工艺现状与关键加工成型设备的局限性以及成型过程中出现的问题,研究开发活性生物颗粒有机肥生产新工艺与空心对辊式成型设备。论述了生物颗粒有机肥生产新工艺的特点及该成型设备的结构组成和工作原理。通过应用表明,该工艺和成型机具结构和参数设计合理,能满足生物颗粒有机肥生产的要求,该技术的研究和成型机具的研制有效地提高了我国生物颗粒有机肥成型的品质和成型率。     

中药材中农药残留现状及标准体系建设研究进展

药用植物凭借其独特、显著的疗效而被作为中医药治疗的主要原材料,然而因其种植及加工过程不规范造成农药残留问题突出。本文对我国中药材中农药残留现状及检测方法的研究进展进行了分析和总结,并对比了不同地区和国家有关农药残留限量标准体系建设情况,提出了我国中药材中农药残留标准体系建设的建议,以期加快我国药用植物农药登记和限量标准制修订,提升中药材质量安全,促进中药产业发展。     

不同增稠剂对农药可分散油悬浮剂稳定性的影响

为明确不同增稠剂对以矿物油为分散介质的油悬浮体系稳定性的影响,以12.5%丙炔·吡嘧(丙炔噁草酮·吡嘧磺隆)可分散油悬浮剂为对象,通过流变学和多重光散射方法,研究了有机膨润土、有机高分子和气相二氧化硅3类增稠剂单独使用及有机膨润土和其他两类增稠剂分别搭配使用对可分散油悬浮剂物理稳定性的影响。结果表明:所有样品的流动特性指数(n)均小于1,为假塑性流体,具有触变性。除有机膨润土和高分子增稠剂Atlox Rheostrux100组合使用时体系更符合Casson方程外,其余样品均更符合Herschel-Bulkley方程。单独使用时,有机膨润土对保证体系稳定的效果相对较好;Atlox Rheostrux 100和Atlox Rheostrux200两种高分子增稠剂的效果差别较大,其中Atlox Rheostrux 100效果更好,这可能是由分子结构差异造成;两种气相二氧化硅类增稠剂由于不能有效形成氢键,效果较差。将有机膨润土和有机高分子增稠剂组合使用时,体系的稳定性有所提升,其中有机膨润土869和Atlox Rheostrux 100组合使用效果更好,体系具有较高的黏度,且具有良好的触变性,物理稳定性优异;有机膨润土869和疏水气相二氧化硅R974组合使用时则效果没有明显的提升。研究表明,流变学和多重光散射两种方法均能较好地表征可分散油悬浮剂的物理稳定性;新型高分子增稠剂和有机膨润土具有协同作用,将二者合理组合添加能大幅提升可分散油悬浮剂的稳定性。     

利用菜青虫细胞检测几种有机溶剂和有机磷农药的毒力

用MTT法研究了5种有机溶剂对菜青虫细胞生长的影响及3种有机磷农药对细胞的毒力。并用微量点滴法测定了3种农药对菜青虫3龄幼虫的毒力。结果表明,5种有机溶剂除二甲苯外,其余4种二甲亚砜、乙醇、丙酮、乙酸乙酯对菜青虫细胞低浓度处理时均无很大毒性。1％浓度处理16小时后细胞存活率仍分别可达99.8％、98％、97.2％、91％。分别用菜青虫细胞测得3种有机磷农药的LC_(50)为:甲基对硫磷,106μs/ml;克线磷,147μg/ml;水胺硫磷,183μg/ml。用微量点滴法测得3种有机磷农药对菜青虫3龄幼虫的LD_(50)分别为:甲基对硫磷,0.458μg/头,克线磷,45.012μg/头;水胺硫磷,0.505μg/头。     

基于土地利用结构优化的土壤有机碳储量预测分析——以内蒙古多伦县为例

土地利用/覆盖变化对陆地生态系统碳循环有着显著影响。基于模糊求解的多目标线性规划,对2020年多伦县土地利用最优结构进行求解,估算了此情景下的土壤有机碳储量。结果表明:多伦县2020年最优土地利用结构为:耕地3.31×104hm~2,林地1.37×105hm~2,草地1.84×105hm~2,水域2 300 hm~2,建筑用地5 600 hm~2,难利用土地2.89×104hm~2。最优土地利用结构下,多伦县耕地、林地和草地土壤有机碳储量分别为2.11×109kg、7.76×109kg和1.03×1010kg;3种土地利用方式下总有机碳储量比2009年增加了1.85×109kg。     

绿洲化过程中塔里木地区农田土壤固碳速率与驱动因素分析

通过对不同时期塔里木北部灌区农田样地土壤采样及剖面分析,结合第二次全国土壤普查和塔里木北部灌区相关农业资料,利用Arc GIS软件分析农田土壤有机碳储量和碳密度变化,揭示绿洲化过程中塔里木北部灌区农田土壤有机碳库的演变规律,分析影响土壤有机碳固存的主要因素。结果表明:1灌区不同类型土壤的固碳能力差异显著,有机碳含量从高至低依次为草甸土、盐土、潮土和风沙土;剖面土壤有机碳含量自上而下递减,其中表层土壤有机碳含量高达2~8 g·kg~(-1)。2剖面0~20 cm和20~40 cm深度的平均土壤有机碳密度分别为(1.36±0.09)kg·m~(-2)和(1.10±0.07)kg·m~(-2),其中风沙土的土壤有机碳密度远低于该区平均水平。3与1981年相比,2011年塔里木北部灌区土壤有机碳密度增量不明显,固碳速率为-0.01~0.03 kg·m~(-2)·a~(-1);不同类型土壤的有机碳密度变化差异显著。总体而言,在绿洲化过程中,新疆塔里木北部灌区的土壤有机碳含量呈增加趋势,土地开发年限及农田管理措施是影响该变化的主要因素。     

Cropping systems modify soil biota effects on wheat (Triticum aestivum) growth and competitive ability

Plants alter soil biota which subsequently modifies plant growth, plant–plant interactions and plant community dynamics. While much research has been conducted on the magnitude and importance of soil biota effects (SBEs) in natural systems, little is known in agro‐ecosystems. We investigated whether agricultural management systems could affect SBEs impacts on crop growth and crop–weed competition. Utilising soil collected from eight paired farms, we evaluated the extent to which SBEs differed between conventional and organic farming systems. Soils were conditioned by growing two common annual weeds: Amaranthus retroflexus (redroot pigweed) or Avena fatua (wild oat). Soil biota effects were measured in wheat (Triticum aestivum) growth and crop–weed competition, with SBEs calculated as the natural log of plant biomass in pots inoculated with living soil divided by the plant biomass in pots inoculated with sterilised soil. SBEs were generally more positive when soil inoculum was collected from organic farms compared with conventional farms, suggesting that cropping systems modify the relative abundance of mutualistic and pathogenic organisms responsible for the observed SBEs. Also, as feedbacks became more positive, crop–weed competition decreased and facilitation increased. In annual cropping systems, SBEs can alter plant growth and crop–weed competition. By identifying the management practices that promote positive SBEs, producers can minimise the impacts of crop–weed competition and decrease their reliance on off‐farm chemical and mechanical inputs to control weeds, enhancing agroecosystem sustainability.     

内蒙河套灌区盐碱低产田建立有机质富积层改土培肥效果

通过连续四年在内蒙古河套灌区低产盐碱地定点、定位试验与定时测土分析，明确了土壤耕层增施有机物料建立有机质富积层，能够改善土壤理化性状，尤其是能降低土壤表层含盐量，提高作物保苗率和显著增加作物产出量。     

Plant protection means used in organic farming throughout the European Union

Following the obligatory implementation of integrated pest management in the European Union (EU), the plant protection means suitable for application in organic agriculture attracted the attention of quite a wide group of potential users. In spite of the common rules of organic production, as well as the uniform principles of placing plant protection products on the market, the availability of products that can be legally used in organic crop protection differs significantly among the Member States. There is a uniform list of 10 basic substances that can be used in the protection of organic crops throughout the entire EU. Twelve Member States have official registers of plant protection products for use in organic agriculture, and the total number of qualified products per country varies from 11 in Lithuania to 576 in Italy. Some products that improve plant vigour or resistance and may be of use in protection of organic crops are placed on the market as biostimulants. They fall under the law that governs fertilisers and the systems of their registration vary widely among the Member States. In addition, there exist a number of products that have been legally introduced onto the markets of some Member States without registration as a consequence of a loophole in the law. The use of unregistered products in organic agriculture raises some doubts, but currently it seems that there is no legal basis on which to explicitly prohibit the practice. © 2017 Society of Chemical Industry