Nanoagroparticles emerging trends and future prospect in modern agriculture system

Increment of technical knowledge has remarkably uplifted logical thinking among scientific communities to shape the theoretical concepts into near product-oriented research. The concept of nanotechnology has overwhelmed almost all forms of lives and has traded its applications in myriad fields. Despite rapid expansion of nanotechnology, sustainable competitions still do exist in the field of agriculture. In current scenario, agriculture is a manifestation demand to provide adequate nutrition for relentless growing global population. It is estimated that nearly one-third of the global crop production is destroyed annually. The loss owes to various stresses such as pest infestation, microbial pathogens, weeds, natural calamities, lack of soil fertility and much more. In order to overcome these limitations, various technological strategies are implemented but a majority of these have their own repercussions. Hence there is a scrawling progress on the evaluation of nanoparticles into agriculture sector which can reform the modern agricultural system. Applications of these nanomaterials can add tremendous value in the current scenario of a global food scarcity. Nanotechnology can address the adverse effects posed by the abundant use of chemical agrochemicals which are reported to cause biomagnification in an ecosystem. Based on these facts and consideration, present review envisages on nanoparticles as nanoherbicides, nanopesticides, onsite detection agro-pathogens and nanoparticles in post harvest management. The review also elucidates on the importance of nanoparticles in soil fertility, irrigation management and its influence on improving crop yield. With scanty reports available on nanotechnology in agriculture system, present review attributes toward developing nanoagroparticles as the future prospect which can give new facelift for existing agriculture system.     

污灌土壤中有机污染物的成分分析及对小鼠的脂质过氧化作用

目的研究某污灌区土壤中有机污染物的组成成分及其对小鼠的脂质过氧化作用。方法以某污灌农田土壤为研究对象,以地下水灌溉农田的土壤为对照,采用超声振荡法提取土壤中的有机污染物,采用气相色谱-质谱联用仪对土壤中的有机物进行分析。选择清洁级昆明小鼠40只,雌雄各半,随机分为溶剂对照组(二甲亚砜)、对照区低剂量组、对照区高剂量组、污灌区低剂量组、污灌区高剂量组。高、低剂量组染毒剂量分别为25、5g土壤干重/(kg·d)。采用灌胃法染毒,每日1次,连续染毒2周。采用试剂盒进行小鼠血清中总超氧化物歧化酶(T-SOD)活力、谷胱甘肽过氧化物酶(GSH-Px)活力、丙二醛(MDA)含量的测定。结果污灌区土壤样品中检测出菲、芘、联苯、芴、萘、2-甲基萘、2,3,6-三甲基色氨酸萘、蒽、2-甲基蒽、1,4-二甲基蒽、荧蒽、4-甲基芘、硫芴、4-甲基氧芴、氧芴、丁基-羟基甲苯、十二烷、新戊基环己烷、3-甲基庚烷、1,2-二甲基环己胺、巴比妥,含量分别为14.3、2.1、1.3、1.1、0.8、1.3、0.4、2.9、7.2、2.3、9.1、0.2、0.4、1.4、1.7、0.37、0.9、0.11、0.02、0.02、0.13mg/kg。对照区土壤样品中检测出3-甲基庚烷、2-甲基庚烷、1,2-二甲基环己胺,含量均为0.01mg/kg。与溶剂对照组比较,对照区高剂量组的T-SOD活力和GSH-Px活力降低,污灌区各组的T-SOD活力、GSH-Px活力均降低,差异均有统计学意义(P<0.05)。污灌区高剂量组T-SOD活力低于对照区高剂量组,差异有统计学意义(P<0.01)。各组MDA含量间比较,差异均无统计学意义(P>0.05)。结论该污灌区土壤已受到一定程度的有机物污染,且可对小鼠体内的脂质过氧化作用产生了一定程度的影响。     

葛根及其种植土壤中钼的单扫描极谱测定法

目的 建立一种新的测量葛根及其种植土壤中钼含量的方法.方法 于2005年11月,在江西省上饶横峰葛基地种植区采集葛根及其所在地区的土壤,采用微波消解单扫描极谱法测定葛根及其种植土壤中钼元素的含量,并与原子吸收法测定结果进行比较、分析.结果 该方法钼的一阶导数电流与钼的浓度的关系曲线的回归方程为:y=0.004 1 000x;线性范围为0.010-1.0μg/ml,r=0.999 0,其检出限为6.0x10-3μg/ml.加标回收率为98.0%-106.0%,RSD为2.2%-4.8%.该法与原子吸收法测定结果比较,经t检验,差异均无统计学意义(P＞0.05).结论 采用单扫描极谱法测量土壤及葛根钼含量,具有结果准确可靠,方法简便快速等特点,值得推广.     

矿化垃圾的重金属淋溶试验研究

通过土柱实验模拟矿化垃圾以及矿化垃圾与污泥混合物在淋溶条件下重金属的淋失情况,并利用污染综合指数法分析矿化垃圾中重金属迁移对地下水的影响.结果表明淋溶的不同阶段对地下水易造成污染的金属元素有所不同,需要分阶段进行监控.淋溶初期需监测[As]、[Cr]、[Co]、[Cu]和[Mn];淋溶中期需监测[Ni]和[Pb];淋溶末期需对[Fe]进行监测.综合污染指数评价表明矿化垃圾以及矿化垃圾与污泥混合土壤的淋溶液对地下水造成潜在污染的最关键因子为Mn,其次是Fe.     

苏州工业园区土壤与蔬菜中重金属污染调查研究

调查研究苏州市常见的12种蔬菜及土壤,并按照国家标准对蔬菜中重金属污染情况进行了评价。结果表明,苏州市工业园区的蔬菜重金属尚未受到相应土壤重金属污染元素的污染,只有少数蔬菜受到了Zn、Pb的污染。     

三峡库区涪陵段库底卫生清理效果

目的探讨三峡水库涪陵段库底卫生清理的方法并评价效果.方法于2002年5-12月开展涪陵区库底卫生清理,范围为坝前135 m抵抗20 a一遇洪水回水线(又称二期迁移线)以下的库底.库底卫生清理对象分为一般性污染源(5 882座)和传染性污染源(68座).一般性污染源包括1 786座畜厩、2 316座粪池、233座化粪池、188座沼气池、202座公共厕所、1 157座普通坟墓;传染性污染源包括22家医疗卫生机构和18座医院垃圾、13座屠宰场、5座兽医站、4座牲畜交易所、6座传染病疫源地、因传染病死亡的人畜墓地.灭鼠与鼠密度监测的范围包括拆迁区、耕作区、人群居住地、仓库、码头、垃圾堆等场所共1 308.62×104m2.主要采用生石灰搅拌、净土回填、漂白粉消毒等方法.结果完成全部库底卫生清理对象的卫生清理工作.灭鼠前农耕区、城市拆迁区鼠密度分别为3.97%和2.97%,灭鼠后农耕区、城市拆迁区鼠密度分别为0.65%和0.33%,分别下降83.63%和88.89%.结论通过库底卫生清理,清除了移民区的传染性污染源和一般性污染源,减少了污染源对三峡水体的污染;通过灭鼠工作的开展,降低了鼠密度,控制了鼠介传染病的流行.     

砷污染区植物种植的筛选研究

目的探讨砷污染区植物种植的筛选.方法于1996-1997年,采集某砷污染区土壤及其种植的玉米、水稻、花生等22种可食植物的新鲜样品测定总砷以及As(Ⅲ)、As(Ⅴ)、甲基胂酸(MMA)、二甲基胂酸(DMA)的含量.结果按测定的土壤的总砷含量排序,由高至低分成A、B、C、D 4个含量范围区,A区为1 301～1 077μg/g,B区为727～504μg/g,C区为127～94μg/g,D区64～28μg/g.同种植物所在的土壤砷含量越高,植物含砷量也越高.同一砷含量区,不同植物品种对砷的富集程度差异很大.植物的不同部位含砷量差异很大,其砷分布一般是根＞叶＞茎＞果.果实的砷含量未超过GB4810-1994<食品中砷限量卫生标准>(0.5μg/g).不同作物中As(Ⅲ)所占4种砷的主要化学形态的构成比顺位是,A区:黄豆＞玉米＞红薯,B区:大米＞玉米＞红薯＞花生.结论在该砷污染区种植果树类植物是相对较安全的,在种植品种选择上除考虑物种对总砷的富集外,还应考虑可食部分As(Ⅲ)的含量构成比.     

土壤氡与室内氡浓度关系的研究

目的了解土壤氡对底层房间的贡献.方法采用ERS1000和RAD7环境测氡仪测量土壤氡及析出率,根据析出率与室内氡关系公式计算了室内氡浓度的变化范围,对所得结果进行了实验验证.结果调查区域土壤氡浓度为(18 000±3 100)Bq·m-3;氡析出率为(8.15±5.55)Bq·m-2·s-1;混凝土地面的氡析出率为(0.72±0.19)Bq·m-2·s-1,普通混凝土结构房屋中氡浓度理论计算范围为11.5～42.4Bq·m-3.实际测量结果(18.9～40.6)Bq·m-3,预测值与实测结果一致.结论在土壤氡浓度低于20000Bq·m-3地区,采用传统建筑方式,不会引起室内氡浓度增高.     

Environmental and serological evidence for the presence of toxocariasis in the urban area of Ancona, Italy

To evaluate the Toxocara spp. eggs environmental contamination of the soil of the urban or suburban area Ancona (Italy), 22 public playgrounds were selected and several cores of soil were taken from any selected areas. To study the Toxocara seroprevalence in the inhabitants of Ancona, blood samples were collected from selected groups of individuals. One hundred and sixty-three blood samples were tested using an enzyme linked immunosorbent assay (ELISA) technique (Lofarma Lab, Milan, Italy) for the detection of IgG-specific antibodies to T.canis excretory–secretory antigens. Toxocara spp. eggs were found in the soil samples from 14 (63.6%) playgrounds. Toxocara seroprevalence was detected in blood specimens from six (8.1%) out of 74 symptomatic individuals and from one (1.1%) out of 89 asymptomatic controls. Among symptomatic individuals, the association between Toxocara seroprevalence and eosinophilia resulted statistically significant (p = 0.029). The high environmental contamination frequency found make necessary to prompt preventive public health measures, such as control of stray animals, treatment of infected pets and hygiene education of the population.     

An enquiry into the respiratory health effects on a rural community of a soil mound erected close to residential property

The health concerns of a rural community were investigated following the erection of a soil mound in close proximity to residential property. Retrospective comparisons were made of respiratory and non-respiratory consultations with general practitioners between the exposed population and a sociodemographically similar comparison population. A 2-year period was examined, 1 year before and 1 year after the mound was erected. In the 1-year period prior to erection of the mound, similar consultation rates for both respiratory and non-respiratory conditions were observed in both populations. In the 1-year period following erection of the mound, the exposed population was more likely to consult for respiratory conditions than the comparison population (OR=4.10, 95% CI 2.26-7.44). No differences were observed for non-respiratory conditions. We identified a significant increase in respiratory consultations in the exposed population following erection of the soil mound. Limitations associated with this type of study should be considered when interpreting the results.