农业四旋翼飞行器的研究

作为农业大国,农林业病虫害的发生对我国农作物产量造成了巨大的损失。当前,我国农田病虫的防范治理大部分依靠人力进行,劳动任务重,危险性也很大。由于农田农作物自身的一些限制条件,一些大型机械难以进行农药喷洒,而四旋翼飞行器的应用可以很好地克服这些缺点。为此,进行了农用四旋翼飞行器的研制,利用单片机作为主控的四旋翼飞行器,可实现自动对农作物进行农药的喷洒,使得农药喷洒变得容易,极大提高了工作效率。     

粮食多场协同干燥系统设计与技术模式应用

以提高粮食干燥过程去水速率、改善干燥品质、减少干燥能耗为目的,基于干燥系统热能结构分析及客观能势利用,综合考虑粮食干燥过程中的多种势场,设计了一种红外热辐射、引风逆混流多场协同干燥系统。结合粮食产地区域特征及农业经营模式,采用了双干燥主塔联机的形式形成干燥装备,实现了系统节能和模式节能。试验结果表明:系统内粮食干燥过程的平均去水速率为2. 95%w. b./h,较传统的横流干燥方式提高2倍以上,粮温降低约11℃,爆腰增率低于1%。     

关于玉米高产栽培技术要点及病虫害防治

在常见的农产品当中,玉米,小麦以及水稻,为人们的生存提供了更加可靠的保障。玉 米在我国分布广泛。因地域和气候的差异,使得玉米的产量也有着非常明显的差别。为促进产 量提升,应结合科学技术的发展,选择更加具备针对性和科学性的栽培技术,并且要加强对玉米 在生长过程中遇到的各种病虫害现象。     

十八大以来中国共产党谋划农民美好生活的认识和探索

十八大以来,党中央始终高度关注着农村民生的发展状况,积极探索谋划农民美好生 活的可行路径,带领全体人民创造美好的幸福生活。本文将梳理十八大以来党对农村建设的探 索和政策演进,为全面建成小康社会提供重要启示。     

邵东县双季晚稻机插秧最佳施肥量试验初报

通过在邵东县魏家桥镇侯家村开展双季晚稻田间"3415"肥效试验,得出每亩最佳施肥 量为氮肥施8.31kg,磷肥3.11 kg,钾肥3.87 kg。N、P、K 比例为1:0.37:0.47。     

玉米新品种选育与栽培技术分析

本文对玉米的新品种的选育和栽培进行分析,以沈育801 为例,分析了该玉米品种的选 育工作和高产栽培技术,为玉米的种植培育提供了一些理论知识,希望可以促进玉米的高产丰 收。     

底墒差异对夏玉米生理特性及产量的影响

研究了底墒差异对夏玉米生理特性及产量的影响。试验结果表明,在夏玉米生育期间极度干旱的条件下,以冬小麦生育期间灌拔节水和抽穗水(各40mm),夏玉米生育期间灌两水(共计100mm)的处理夏玉米产量最高,达7466.58kg/hm2。而且该处理的叶面积、光合速率、蒸腾速率等生理指标高于其余各处理,气孔阻力和叶温等生理指标则低于其余各处理,以上各生理指标的变化是由于前茬冬小麦不同生育期灌溉而造成的。本试验同时表明,研究作物的水分问题应与特定的种植制度相结合。     

去除取样法估算鳄蜥的种群数量

一直以来对野外鳄蜥种群数量的调查主要使用样线法和标志重捕法。为了更好地估算鳄蜥的种群数量,本研究在2016年7月25日至31日使用去除取样法对广西大桂山鳄蜥国家级保护区内鱼散冲的1.9 km的样线进行了调查。结果显示,鱼散冲的鳄蜥种群数量为101只,种群密度为53只/km。鳄蜥由于其特殊的栖息环境和生活习性,适合于采用去除取样法调查其种群数量和密度。     

不同种源丝栗栲种子性状变异

为了探讨丝栗栲(Castanopsis fargesii)种子的变异规律,对采自贵州省荔波县、都匀市和三都县3个地理种源13个家系的丝栗栲种子的长、宽、长宽比和百粒重进行对比分析。结果表明:3个不同地理种源的丝栗栲种子的种子长、种子宽、长宽比和种子百粒重的性状差异达到极显著水平;种源间各性状指标的变异幅度较大,分别为种子长0.176%～4.034%、种子宽1.443%～6.389%、长宽比1.392%～4.808%、百粒重2.773%～13.470%。荔波种源的各项指标变异系数均为最大,都匀种源各项指标的变异系数均为最小;各指标间均具有极显著相关性,种子长与种子宽、百粒重呈极显著正相关,与种子长宽比呈极显著负相关;种子宽与种子长宽比呈极显著负相关,与百粒重呈极显著正相关;种子长宽比与百粒重呈极显著负相关。3个种源中,都匀种源的综合指标最优,可作为优良种源进行良种培育。     

Effects of different green manure treatments on soil apparent N and P balance under a 34-year double-rice cropping system

Purpose

Although green manure rotation is often used to promote soil fertility and crop yield, the effects of this management practice on the nitrogen or phosphorus balance and the relationship between nutrient balance and the increase in soil nutrients have not been systematically studied.

Materials and methods

We investigated the apparent nitrogen and phosphorus balances and their associations with soil nitrogen and phosphorus increases, respectively, in a 34-year-old experimental site with various green manures and rice rotations using linear and logistic models. Cropping treatments included a rice-rice-winter fallow treatment as a control (RRW) and three green manure rotation treatments: rice-rice-ryegrass (RRR), rice-rice-oil rape (RRO), and rice-rice-Chinese milk vetch (RRC).

Results and discussion

We found that apparent nitrogen and phosphorus balances of RRR, RRO, and RRC were 164, 162, and 149 kg hm^?2, which were all significantly lower than 200 kg hm^?2 of RRW (P <?0.05). Moreover, the optimal fitted model of the relationship between cumulative nutrient balance and the increase in soil nutrients was different among treatments. Specifically, the correlation coefficients of cumulative nitrogen balance and soil nitrogen increase of RRR, RRO, and RRC in the linear model (0.49, 0.80, and 0.63) were all significantly lower than in the logistic model (0.81, 0.90, and 0.82). The correlation coefficients of cumulative phosphorus balance and increase in soil phosphorus of RRW in the linear model (0.81) were significantly lower than in the logistic model (0.91). Parameter analysis of the optimal fitted model revealed that RRC would increase the storage capacity of soil nitrogen and decrease the rate of soil phosphorus accumulation.

Conclusions

Our results suggested that long-term rice-rice-green manure rotation could significantly change the apparent nitrogen and phosphorus balance and their association with soil nitrogen and phosphorus content, respectively. Our study highlights the importance of green manure rotation in an agro-ecological environment and soil fertility in a double rice cropping system in red paddy soil.