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1.
蚂蚁有爱     
我喜欢各种各样的小动物,昆虫,天上的飞鸟,以及四季的更替,无论刮风,下雨,晴天,雪天,只要在自然的环境里,我就会感到很幸福。 这与我的童年有关,那时候没有玩伴,一切不会讲话的事物都是我的朋友,他们教给我许多做人的道理,他们很忠诚,如果让我选择,我更喜欢他们。  相似文献   

2.
青山孕绿水,绿水生奇景。从拥挤烦嚣的大都市步入三水云东海,一种绿的色彩,绿的空气,绿的气氛向我们袭来,浑身顿觉清爽和快慰,一种自得其乐的心情油然而生,使我们感到绿的温馨,绿的情怀,绿的快感。踏羊肠小道,穿深山密林,我们置身于“曲径通幽”的诗境中,抬头望天,天高云淡;举目远眺,群山逶迤,古木参天;俯视碧湖,清澈见底。一畦畦桑林,一间间茅舍。一派田园风光,一片诗情画意。攀树枝,跨小溪,翻小丘,终于,“大塱涡之水天上来”美景呈现在我们面前。大塱涡舒展柔情,以妩媚、清丽、温柔、纯朴的姿容展示着大自然的神功造化。湖里的水剔透玲珑,纤尘不染,湖中倒影,树影婆娑相映成趣。碧水上欢游的小鸭,“呷呷呷”地唱着自己的歌,  相似文献   

3.
1993年5月5日,农历癸酉年闰3月14日,为立夏节气,对西北地区东部的人们,这天是一个“黑色”的日子,大自然暴虐地在中国灾害史上写下了残酷的一页.春夏之交,腾格里沙漠东南的中卫县呈现出一派生机盎然,朝气蓬勃的景象,天气晴朗,微云淡抹,暖意宜人.但是,在下午6时许,沙漠东北部的天际突然竖起一道黑墙,越升越高,迅速向前推进.黑色的帏幕很快向两边拉开,帏幕后边窜起无数沙云,转眼将夕阳吞没,同时,地面上升起黑色的、灰色的、黄色的尘云交织在一起,翻滚着,变幻着,现出千奇百怪的形象.接着,帏幕四合,一声巨响,一瞬间白昼变成黑夜,强大的气流卷着沙尘横扫过来,室内尘土弥漫,呛得人喘不过气来,这就是黑风!沙暴!  相似文献   

4.
初中阶段的学生,虽然已经具备了一定的判断能力,但他们的思想还不够成熟,容易冲动,因此,作为初中思想品德教师,不仅要注重教学效率,更要重视对学生思想行为的引导,使他们树立良好的人生观、世界观以及价值观,养成良好的生活习惯,最终成为高综合素质的人才。但是当前的初中思想品德教学存在各种问题,教学质量不高,学生不够重视,因此,思想品德教师要采用有效方法,提高教学效率,提升学生的思想。  相似文献   

5.
纵观中外古今,许多著名的作家、诗人、作曲家、画家、发明家,都有漫游名山胜川、热爱大自然之爱好。有趣的是,大自然的山光水色,奇花异草,鱼虫鸟兽,幽美的环境,葱绿的大地,往往能触发他们创作或发明的灵感,写出佳作妙篇,流芳千古,或在科学发明方面又有新招。奥地利作曲家、“世界圆舞曲之王”约翰·施特劳斯,有一次他在风光迷人的维也纳森林里,翠绿的景象,和煦的阳光,悦耳的鸟鸣,低吟的和风,淙  相似文献   

6.
三三 《环境》2006,(8):39-40
建筑,一首凝固的音乐。 一首用所有的石头和建材筑成的,如雕塑般,如诗歌般,既静态又动感的音乐。 好的艺术是不由亵渎的,更需要读懂它性灵的人。好的建筑更需要仰望,那些思想的碎片、艺术的精华、生活的智慧,藏在片瓦只木中,因为无语,故由人评说。 建筑,代表着一个时代,又常跨越一个时代。它用一个时代的语言和思想来诠释,却在另一个时代得到全新的诠释。每一个时代的评说各有千秋,建筑又白成一格,但千百年过去了,若干个时代变迁了,民族的建筑,却总有一种传承的核心及同质的文化。 犹如一栋栋凝固的音乐史诗,尽管历尽桑田,却独自屹立无言,让历史洗礼。 留给我们的,是无限的注脚……以及更多的仰望。于是,我们期待从仰望建筑开始,解读每一个建筑的心声,通过那个时代的语言,了解我们历史的内核与文化的传承。[编者按]  相似文献   

7.
山林怪兽     
在古老而广袤的中华大地上,栖息着许多山林怪兽,如“两不像”的马虎,“四不像”的麋鹿,“五不像”的貘,“六不像”的扭角羚……然而,随着岁月的流逝,环境的变迁,特别是人为的原因,今天,这些动物有的灭绝了,有的为数极少,濒临灭绝。  相似文献   

8.
一、课题的提出背景 污水处理技术,经过广大从业人员的努力,得到了飞速的发展,使水体污染的发展速度,得到了很大程度的抑制.但是,纵观我国的整个治污形势,仍然不容乐观,经常出现一些企业,违反国家的环保政策,把没有经过任何处理的生产污水,直接排放到自然水系,使当地的环境污染更加严重,甚至给当地人的生活造成很大的困难,更有甚者,一些大型的企业,也常发生偷排污水的情况.这些问题的一再暴光,使人们看到了政府对环境污染进行治理的决心,也暴露出所有这些违法排污的原因,无怪乎就是利益的驱动.  相似文献   

9.
从我做起     
受尽浑浊空气的困扰、隆隆噪声的煎熬以及污泥臭水的侵袭,富裕了的人们幡然觉悟,渐渐摒弃那对灯红酒绿的追求,厌恶那对权力与金钱的膜拜,人之本性开始回归,乐于与大自然和谐共处。劳碌终日,难得偷闲,双休假日,要么举家大小,要么邀朋聚友,或野餐,或垂钓,或漂流,或漫步。更有甚者,当上个“业余农夫”,亲尝一下“锄禾日当午”的滋味。返璞归真,向往环境美,已成为一种绿色的潮流,绿色的享受。  相似文献   

10.
<正>阅读是准备,写作是启程远行;准备不好,必然行之不远;良好的阅读习惯、正确的读书方法为写作打下坚实的基础,否则,写作犹如空中楼阁,教学有年,履职尽责,天长日久,积累经验点滴,列举如下。一、认识读书的重要性阅读是写作的基础,只有有了一定的阅读积累,在写作中才能泉思如涌。读书之妙,如人饮水冷暖自知,读书久了,能够深入其中,会感觉到"外物之味,久则可厌;读书之味,愈久愈深";读书能够丰富思想,打造完全的人格,形成敏捷的思维,增进理解能力,提高语言素养,升华人生智慧;无论是刀笔小吏还是国学大师,其语言的素养和文化的修为大都是"读"出来的。读诵不辍者,话语天成,言辞有味说理深刻有丰富的文化内涵能  相似文献   

11.
An investigation of gaseous elemental mercury concentration in atmosphere was conducted at Beijing and Guangzhou urban, Yangtze Delta regional sites and China Global Atmosphere Watch Baseline Observatory (CGAWBO) in Mt. Waliguan of remote continental area of China. High temporal resolved data were obtained using automated mercury analyzer RA-915 . Results showed that the overall hourly mean Hg0 concentrations in Mt. Waliguan were 1.7± 1.1 ng/m3 in summer and 0.6±0.08 ng/m3 in winter. The concentration in Yangtze Delta regional site was 5.4±4.1 ng/m3, which was much higher than those in Waliguan continental background area and also higher than that found in North America and Europe rural areas. In Beijing urban area the overall hourly mean Hg0 concentrations were 8.3±3.6 ng/m3 in winter, 6.5±5.2 ng/m3 in spring, 4.9±3.3 ng/m3 in summer, and 6.7±3.5 ng/m3 in autumn, respectively, and the concentration was 13.5±7.1 ng/m3 in Guangzhou site. The mean concentration reached the lowest value at 14:00 and the highest at 02:00 or 20:00 in all monitoring campaigns in Beijing and Guangzhou urban areas, which contrasted with the results measured in Yangtze Delta regional site and Mt. Waliguan. The features of concentration and diurnal variation of Hg0 in Beijing and Guangzhou implied the importance of local anthropogenic sources in contributing to the high Hg0 concentration in urban areas of China. Contrary seasonal variation patterns of Hg0 concentration were found between urban and remote sites. In Beijing the highest Hg0concentration was in winter and the lowest in summer, while in Mt. Waliguan the Hg0 concentration in summer was higher than that in winter. These indicated that different processes and factors controlled Hg0 concentration in urban, regional and remote areas.  相似文献   

12.
根据1979年5月,8月,11月胶州湾水域调查资料,并且与近几十年来的调查资料进行对比分析,探讨和研究胶州湾重金属Hg的平面分布、垂直分布、季节分布以及发展趋势.结果表明:胶州湾东北部海域春季污染较为严重,西南部的污染程度相对较轻;春季和夏季的表层含量大于底层含量,秋季时底层含量高于表层含量;而且春季Hg污染较为严重,秋季水质状况最好.从历史资料来看,1979年到1982年,Hg污染在加剧;1982年到1997年,从污染严重到缓和,在1997年就达到了一类水质的要求;1997年到1999年,水质更加清洁.  相似文献   

13.
刁江水体多相介质中As,Zn和Pb的空间和季   总被引:5,自引:0,他引:5  
调查了广西刁江河水中As,Zn和Pb的溶解态、悬浮颗粒态分布情况及季节变化,以及3种重金属在不同粒级沉积物中的分布情况. 结果表明:刁江流域河水与沉积物中3种重金属污染在流域尺度上的分布存在差异,沉积物污染更为严重. 与土壤污染一致,沉积物中3种重金属的污染范围扩散延伸到距离污染源近200 km的下游区域,其中车河矿区对As污染的贡献率明显高于大厂矿区,而对Pb污染的贡献率明显小于大厂矿区;不同重金属在水体中的赋存形态存在差异,河水中悬浮颗粒态Pb所占比例远高于As和Zn,这与3种重金属矿物的稳定性以及在不同粒级沉积物中的富集特征有关;河水中重金属的赋存形态存在季节差别,丰水期悬浮颗粒态重金属所占比例明显高于枯水期.   相似文献   

14.
Oxidative stress and DNA damages induced by cadmium accumulation   总被引:22,自引:0,他引:22  
Experimental evidence shows that cadmium (Cd) could induce oxidative stress and then causes DNA damage in animal cells, however, whether such effect exists in plants is still unclear. In the present study, Vicia faba plants was exposed to 5 and 10 mg/L Cd for 4 d to investigate the distribution of Cd in plant, the metal effects on the cell lipids, antioxidative enzymes and DNA damages in leaves. Cd induced an increase in Cd concentrations in plants. An enhanced level of lipid peroxidation in leaves and an enhanced concentration of H2O2 in root tissues suggested that Cd caused oxidative stress in Vicia faba. Compared with control, Cd-induced enhancement in superoxide dismutase activity was significant at 5 mg/L than at 10 mg/kg in leaves, by contrast, catalase and peroxidaseactivities were significantly suppressed by Cd addition. DNA damage was detected by neutral/neutral, alkaline/neutral and alkaline/alkaline Comet assay. Increased levels of DNA damages induced by Cd occurred with reference to oxidative stress in leaves, therefore, oxidative stress induced by Cd accumulation in plants contributed to DNA damages and was possibly an important mechanism of Cd-phytotoxicity in Vicia faba plants.  相似文献   

15.
The aerosol number concentration and size distribution were measured with the newly developed Wide-range Particle Spectrometer in summer and winter of 2006 at the urban site of Jinan City.Here reported the characteristics of fine particles of the different observation seasons.Relative high number concentrations for the particles in the diameter range of 10-500 nm were observed in both seasons.It was found that the dominant number distributed in particle diameter smaller than 100 nm and the percentage over the number concentration of all air particles is much higher than what has been measured in other urban sites over the world.The number mean diameter in summer was much smaller than in winter,strongly suggesting the different origin of ultrafine particles in different seasons.That is, particles in ultrafine mode mainly came from nucleation and new particle formation in summer while from traffic emission in winter. The diurnal variation also supported this point.Number concentration in the diameter range of 10-200 nm got their peak values at noontime,well correlated with the mixing ratio of SO_2 and the intensity of solar radiation in summer.While in winter,those in the same diameter range showed the main peaks during the traffic hours happened in the morning and evening.  相似文献   

16.
IntroductionAtrazine(2chloro4ethylamino6isopropylaminostriazine)isoneofthemostwidelyusedselectivepreandpostemergenceherbicidesforthecontrolofbroadleafandgrassyweeds.ThisherbicideisprimarilyusedincorncroppingsysteminNortheastandNorthofChina,andasoftentim…  相似文献   

17.
Massive amounts of pig manure are produced by intensive pig farm in China, and the composition of pig manure has changed much due to the use of feed additives. However, little is known about the exact Cu (copper) feed as additives or present as contaminants in pig feed and the residues in feces. One hundred and thirty-seven feeds and one hundred and forty-two fecal samples from 48 pig farms were collected in Beijing and Fuxin cities in 1999 and 2005, respectively. The concentrations of Cu were in the range of 6.86-395.19 mg/kg in the feed samples, and the mean values were in the order of weaner〉 grower-finisher〉 sow's feeds. The high concentrations over EU recommendations implied that excessive levels of Cu are fed on many pig farms in Beijing and Fuxin. Cu was also present in high concentrations in feces, and concentrations were highly variable. Cu concentrations in the feces from grower-finisher and weaner pigs were significantly greater than feces of sows. The super-intensive and small-scale farms had higher levels of Cu in feces than the middle farms. Cu concentrations in pig feces were approximately 5-times greater than in pig feeds. Feed management in grower-finisher pigs on super-intensive and small-scale pig farms is needed to reduce high Cu concentrations in feces and risks to soil contamination while feces are land-applied.  相似文献   

18.
The aim of this study was to characterize mercury (Hg) contamination in the coastal waters of the Southern Baltic Sea, and to investigate transformations of Hg in the initial links of the marine food chain. Concentrations of Hg in water, particulate matter, plankton and macrophytes at various stations in the coastal zone (a bay with restricted water exchange, near an industrial city, river mouths, and the open sea) were measured in 2006–2008. Hg concentrations observed in the Southern Baltic varied greatly, showing the highest average values in all environmental compartments near the river mouths. In shallow, sheltered parts of the gulf, where water exchange is restricted, Hg concentrations in the water and in macrophytes were elevated relative to those in the coastal zone of the deeper part of the bay and in the open Baltic. Distance to the river mouth, terrestrial runo , and quantity and quality of organic matter were more important than seasonal variations in controlling Hg and HgSPM concentrations in water samples. Mercury concentrations in the surface microlayer at the air/sea interface were over 10 times higher than those in the bulk surface water. Concentrations of Hg in macrophytes in the winter were significantly higher than those in the warm seasons (spring, summer, autumn). This was probably the combined e ect of higher availability of Hg in porewaters and leaf growth inhibition.  相似文献   

19.
青岛大气气溶胶水溶性无机离子的粒径分布特征   总被引:7,自引:0,他引:7       下载免费PDF全文
为了解大气颗粒物中水溶性离子的来源及环境效应,利用安德森采样器连续采集青岛近海2008年1~12月大气颗粒物分级样品,用离子色谱法分析其中主要的水溶性离子,并讨论其粒径分布特征.结果表明, NH4+、K+、Cl-、NO3-、PO43-、SO42-主要存在于粒径小于2.1μm的细粒子中,Na+、Mg2+、Ca2+、F-则主要存在于粒径大于2.1μm的粗粒子中.各离子的粒径分布存在明显的季节变化.NH4+、K+和SO42-四季均主要分布于细粒子中,而Mg2+和Ca2+则主要分布在粗粒子中,两者均在3.3~4.7μm出现峰值;Na+在春、夏、秋3个季节主要存在于粗粒子中,集中分布在3.3~7.0μm粒径范围内,而在冬季则集中分布于0.43~1.1μm且细粒子含量高于粗粒子;春季Cl-在粗粒子中分布较多,尤以2.1~3.3μm范围内的最为突出,而其他3个季节均是细粒子比例明显偏高;NO3-春、夏两季在粗、细粒子中的含量各占50%,秋、冬季节均为细粒子占多数;PO43-夏季只出现在0.65~1.1μm以及>11μm的粒径范围内,粗粒子占95%,其他3个季节则是细粒子含量较高;春季F-在3.3~4.7μm出现峰值,夏季各粒径均未检出,而秋、冬两季粗、细粒子各占50%.K+、NH4+、F-、Cl-、NO3-、SO42-和PO43-受供暖期燃煤取暖的影响较大.K+和NH4+在供暖期和非供暖期峰值均出现在0.43~0.65μm粒径范围;F-供暖期在0.43~0.65μm和3.3~4.7μm粒径段出现峰值;供暖期Cl-的峰值出现在0.43~0.65μm粒径段,而在非供暖期,则出现在2.1~3.3μm的粗粒径段;SO42-和NO3-在供暖期和非供暖期的峰值均出现在0.43~0.65μm和3.3~4.7μm粒径段;供暖期PO43-的最大峰值出现在0.43~0.65μm粒径段,而在非供暖期其最大峰值出现在3.3~4.7μm粒径段.  相似文献   

20.
主要调查研究环渤海湿地芦苇对TC、TN、TP的吸收通量。调查表明,2008年环渤海湿地的芦苇面积为20.08×104hm2。2009年,芦苇总生物量在7月、10月和11月的调查结果分别为267.2×104t、183.4×104t和138.0×104t。7月、10月和11月,芦苇对TC的吸收通量分别为115.58×104t、80.68×104t、64.23×104t;对TN的吸收通量分别为4.03×104t、1.45×104t、0.84×104t;对TP的吸收通量分别为0.37×104t、0.10×104t、0.031×104t。  相似文献   

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