Could biochar amendment be a tool to improve soil availability and plant uptake of phosphorus? A meta-analysis of published experiments

Environmental Science and Pollution Research - As one of the most important nutrients for plant growth, phosphorus was often poorly available in soil. While biochar addition induced improvement of...     

Adsorption of Ammonium by Graphene Oxide-Based Composites Prepared by UV Irradiation and Using as Slow-Release Fertilizer

A novel sodium alginate-grafted poly(acrylic acid)/graphene oxide (NaAlg-g-PAA/GO) composite hydrogel was prepared via ultraviolet irradiation, and characterized by infrared spectroscopy spectrometer. X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy. It was employed to adsorb NH₄⁺ from aqueous solution and used as slow-release nitrogen fertilizers (SNFs). Result indicated that the adsorption process for NH₄⁺ reached equilibrium within 50 min, with the adsorption capacity of 6.6 mmol g^?1 even if 30 wt% GO was incorporated. The results of adsorption kinetic and isotherm were well described by the pseudo-second-order and Freundlich model. The thermodynamics analysis showed the adsorption process was spontaneous. The study indicated excellent water-holding ratio of soil with 2 wt% SNFs was 81.2%, and nitrogen release was up to 55.1% within 40 days in soil. Overall, NaAlg-g-PAA/GO could be considered as an efficient adsorbent for the recovery of nitrogen with the agronomic reuse as a fertilizer.     

榆林市某园区兰炭企业存在问题及解决对策

兰炭是榆林市的重要产业之一,但由于兰炭"粗放"的生产方式,对区域环境产生一定影响。为推进兰炭绿色健康发展,本文针对榆林市某园区内兰炭企业进行调研,了解该企业存在的主要问题,并提出相关建议。     

RF多功能芯片on-wafer评估系统的研究

评估RF多功能芯片在不同环境温度下的性能指标是十分重要的,从分析射频多功能芯片功能和主要性能指标出发,研制了一款自动化芯片在片评估系统。采用上位机进行多种芯片工作状态和设备仪器状态控制,实现了芯片在各种不同工作状态不同温度下的测试数据采集、判断和保存。经实际评估验证,该评估系统能高效高可靠性的完成射频多功能芯片在不同环境温度下的on-wafer级性能评估。     

绿黄隆在麦茬土壤中的残留及其对后茬水稻的影响

应用核素示踪技术，以１４Ｃ－绿黄隆进行麦茬土壤残留及其对后茬水稻影响的盆栽试验研究。结果表明，施于麦地的绿黄隆经过麦季（２０６ｄ）后有２５％～３０％残留于土壤；经过麦－稻两季（３２６ｄ）后仍有约１５％的绿黄隆残留在土壤中；麦茬土壤中残留的绿黄隆严重影响后茬水稻根系生长，进而影响植株的生长发育；水稻植株残留量和转移系数是根系＞＞茎叶＞稻谷，在各部位的分布是不均匀的。     

新垦赤红壤不同轮作的养分变化

五年的研究结果是:赤红壤耕垦之后只要采取合理的轮作和结合适当的秸秆返回措施,它的肥力就可以得到保持,而且还可以获得显著提高。在四种轮作形式中,效果最明显的为1:1,它的土壤有机质、全量N、P、K含量比轮作前分别提高了L 22、1.84、2.27和0.06倍1:2和2:1的效果较差,分别提高了0.57、0.83、2.08、0.39倍和1.02、0.91、1.46、-0.07倍,0:1的由于没有轮作,加上每年把长好的草皮铲走,导致了土壤有机质、全氮量反而比轮作前下降了6.5％和25.0％。随着轮作土壤养分的提高,土壤物理和微生物状况也获得了改善。     

垃圾堆肥在北方潮土地区的农用研究

研究结果表明：垃圾堆肥具有促进作物增产的作用，并不会引起重金属污染。但在北方潮土地区，垃圾肥施用量以４０～５０ｔ·ｈｍ－２·茬－１为宜。过量施用垃圾肥不仅会引起施肥经济效益明显降低，且会引起土壤砂化。研究还表明，粘质土壤对垃圾肥有更大的容纳量。     

Na_2CO_3/H_2O_2“稳定”的CO_2的型体研究(Ⅱ)——“稳定性二氧化氯”溶液的UV吸收光谱、纸层析特性、微观结构和离子色谱分析

本文对以稳定剂H_2O_2和Na_2CO_3与ClO_2制备的所谓"稳定性二氧化氯"溶液的UV吸收光谱、纸层析特性、微观结构及离子色谱进行了分析,并与纯NaClO_2及ClO_2溶液做了对比.结果表明,“稳定性二氧化氯” 与NaClO_2在UV吸收光谱、层析比移值、微观结构、离子色谱这几方面都具有很好或极其相似的一致性 表明“稳定性二氧化氮’与NaClO_2溶液中氯氧化物存在型体的一致性.因此,认为“稳定性二氧化氯“溶液中ClO_2是以亚氯酸盐ClO_2~-的型体存在的.