Phosphorus Transfer and Distribution in a Soybean-Citrus Intercropping System

来源 :Pedosphere | 被引量 : 0次 | 上传用户:ESC_liangzi
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
A mini-plot field experiment was conducted on a loamy clay Oxisol to compare and evaluate P absorption and transfer in plant organs and P movement in soil profile at three P application depths under the soybean-citrus intercropping versus the monoculture using a 32P tracer technique. Total P absorption (Pt) by soybean and P accumulation (Pa) in soybean organs decreased significantly (P < 0.05) under the intercropping in contrast to the monoculture. With intercropping, when 32P was applied in topsoil (15 cm soil layer), total 32P absorption (32Pt) in soybeans was significantly lower (P < 0.05), but when 32P was applied to deeper soil layers (35 or 55 cm soil layer), 32Pt in soybeans was significantly greater (P < 0.05). The percentage of P in leaves to total P (Pa/Pt) and 32P in leaves to total 32P (32Pa/32Pt) for soybean were (?) 25% and those of root (?) 12%. When P was applied in topsoil and 55 cm soil layer, no significant differences were found between intercropping and monoculture for Pt of citrus. The P absorbed by citrus was transferred rapidly to the growing organs of aboveground during the experiment, and the speed of transferring to the growing organs slowed when P was applied to the deeper soil layers. In intercropping, P mobility was heightened in the soil profile, and P in deeper soil layers moved up to topsoil more rapidly. A mini-plot field experiment was conducted on a loamy clay Oxisol to compare and evaluate P absorption and transfer in plant organs and P movement in soil profile at three P application depths under the soybean-citrus intercropping versus the monoculture using a 32P tracer technique. Total Psorption (Pt) by soybean and P accumulation (Pa) in soybean organs decreased significantly (P <0.05) under the intercropping in contrast to the monoculture. With intercropping, when 32P was applied in top soil (15 cm soil layer) 32Pt in soybeans was significantly lower (P <0.05), but when 32P was applied to deeper soil layers (35 or 55 cm soil layer), 32Pt in soybeans was significantly greater (P <0.05). The percentage of P in leaves to total P (Pa / Pt) and 32P in leaves to total 32P (32Pa / 32Pt) for soybean were 25% and those of root (?) 12%. When P was applied in topsoil and 55 cm soil layer, no significant differences were found between intercropping and monoculture for Pt of citrus. The P absorbed by citrus was transferred rapidly to the growing organs of aboveground during the experiment, and the speed of transferring to the growing organs slowed when P was applied to the deeper soil layers. in the soil profile, and P in deeper soil layers moved up to topsoil more rapidly.
其他文献
田家英,原名曾正昌,1922年1月生于四川成都。他自幼失去父亲,就在他刚刚读完初中一年级之后,母亲病故,家庭经济困难。田家英不得不中途辍学,在一家药铺当学徒。但他并不屈从
根据《音乐课程标准》中关于“课程资源的开发与利用”方面的要求,学校组织一支符合自身实际的铜管乐队,为丰富学校课外活动,提高学生文化艺术修养,促进学校“两个文明”建设等方面都能起到积极的推动作用。但是,针对高中的学习课程多学习任务重的实际情况,组建一支高中生的铜管乐队也是相当不易的。现以我校35人的铜管乐队为例,谈谈我的体会:  一、组织编配科学合理  铜管乐队(BrassBand)有固定的乐队编制
【摘 要】现代篮球运动迅猛发展,竞争日趋激烈,战术变化极为复杂,对裁判员的要求也越来越高。强大的自信心;稳定的情绪状态;丰富的临场经验等更应该成为当代大学生裁判员的基本素质。篮球裁判员在临场工作中会受到各种因素的影响,会出现“怯场”的现象,导致常常会出现误判、漏判、错判。本文为能够迅速提高裁判能力,确实准确判断比赛的合法进攻与防守,为现代篮球高素质裁判员的培养提供理论指导。  【关键词】篮球学生裁
在制造业,服务器作为信息化系统的硬件载体,已经广泛应用于各种企业信息化项目当中。然而在经历了经济危机的阵痛后,国内制造业对于服务器的需求已趋于理性。虽然企业在信息化方
体育,是一个民族崛起的重要标志。为进一步提高我国竞技体育水平,体育中专生的培养就显得尤为重要。但就目前来说,我国体育中专生暴露出了许多问题,其中诸多问题与其心理健康状况直接相关,亟待解决。  因此,重视体育中专生的心理健康教育,研究他们的心理健康现状并找出相应对策,使他们能有一个健康的心理,人格、文化、训练得到和谐、全面的发展,是摆在体育中专教育工作者面前的一个十分紧迫、严肃的问题。  一、体育中
期刊
管理层业绩预测对于证券定价和投资决策都具有重要作用,是资本市场理论研究和实务分析中关注的热点问题。但是,长期以来,以上市公司营收计划为代表的管理层未来展望信息却被理论
【摘 要】现代社会对大学生的要求越来越高,学生面临的心理和身体压力也越来越大。学校为了培育出能够适应激烈社会生活的优秀大学生,也在不断推进教学改革。而体育教学改革正是学校面临的改革任务之一。虽然体育教学改革正在稳步前进,但其中仍然存在着一些问题,阻碍着体育教学改革的发展。因此,本文主要围绕当前大学体育教学改革的现状和其中的问题作简要分析,希望为我国体育教学事业建言献策。  【关键词】大学体育 教学
通过直觉模糊覆盖概念将覆盖粗糙集模型进行推广,提出一种基于直觉模糊覆盖的直觉模糊粗糙集模型.首先,介绍了直觉模糊集、直觉模糊覆盖和直觉模糊逻辑算子等概念;然后,利用