土地资源是三大地质资源(矿产资源、水资源、土地资源)之一，是人类生产活动最基本的资源和劳动对象。人类对土地的利用程度反映了人类文明的发展，但同时也造成对土地资源的直接破坏，这主要表现为不合理垦植引起的水土流失、土地沙漠化、土地次生盐碱化及土壤污染等，而其中水土流失尤为严重，乃当今世界面临的又一个严重危机。据估计，世界耕地的表土流失量约为230亿吨/年。

有人认为酸雨是一场无声无息的危机，而且是有史以来冲击我们最严重的环境威胁，是一个看不见的敌人。这并非危言耸听。随着工业化和能源消费增多，酸性排放物也日益增多，它们进入空气中，经过一系列作用就形成了酸雨。

赤潮虽然自古就有，但随着工农业生产的迅速发展，水体污染日益加重，赤潮也日趋严重。我国自1933年首次报道以来，至1994年共有194次较大规模的赤潮，其中60年代以前只有4次，1990年后则有157起。石油类污染对水质和水生生物有相当大的危害。漂浮在水面上的油类可迅速扩散，形成油膜，阻碍水面与空气接触，使水中溶解氧减少。油类含有多环芳烃致癌物质，可经水生生物富集后危害人体健康。二氧化硫主要由燃煤及燃料油等含硫物质燃烧产生，其次是来自自然界，如火山爆发、森林起火等产生。二氧化硫对人体的结膜和上呼吸道粘膜有强烈刺激性，可损伤呼吸器管可致支气管炎、肺炎，甚至肺水肿呼吸麻痹。短期接触二氧化硫浓度为0.5毫克/立方米空气的老年或慢性病人死亡率增高，浓度高于0.25毫克/立方米，可使呼吸道疾病患者病情恶化。长期接触浓度为0.1毫克/立方米空气的人群呼吸系统病症增加。另外，二氧化硫对金属材料、房屋建筑、棉纺化纤织品、皮革纸张等制品容易引起腐蚀，剥落、褪色而损坏。还可使植物叶片变黄甚至枯死。

保护环境，人人有责。

演讲稿大全字篇2

what would you do if you failed? many people may choose to give up.however, the surest way to success is to keep your direction and stick to yourgoal.

on your way to success, you must keep your direction. it is just like alamp, guiding you in darkness and helping you overcome obstacles on your way.otherwise, you will easily get lost or hesitate to go ahead.

direction means objectives. you can get nowhere without an objective inlife.

you can try to write your objective on paper and make some plans to achieveit. in this way, you will know how to arrange your time and to spend your timeproperly. and you should also have a belief that you are sure to succeed as longas you keep your direction all the time.

演讲稿大全字篇3

hello, everyone.

" dad, mom" is a very kind call, fatherly motherly love, a contains unlimited touching words. in this world, only the mother's love for her children is the most sincere, the most selfless. however, parents know love, parents know dedication, why can't we have a heart of thanksgiving? therefore, the topic of my speech today is "the heart of thanksgiving".

thanksgiving is a virtue, is a long history of cultural heritage. its source is like the flowing streams of love. memories of history, we were so touched by the story of a mother to son: ancient, can become the big industry, at three moves, for future generations to leave" told " the story. in modern times, a well-known anti-japanese general ma jingzhai 's mother, she was arrested, the face of the japanese threat, without fear, decided to allow her son to the war of resistance against japan, then fast to death. ma jingzhai wrote the" great mother, live on in spirit, son of bearing mother, continue to struggle.". this one case, a hymn to love, do not reflect a mother do great?

my mother is an ordinary, but, she is in a breezy morning gave me life; she is in transverse oblique rain on the road of life, gave me strength; she is, in my setbacks, gave me confidence; and she was, in my be big with pride when my humble church. from the bottom of my grateful to her for years, although lost her youth and beauty, but she in my mind forever is cupid, aphrodite. hard although took her beautiful singing voice, but her every word is in my heart jin yan rhyme, it is the mother of its own actions tell me one of the most common sense: love is selfless dedication.

remember the summer morning, it was raining hard, i said:" my mother, the rain is so big, don't go to school, " she said, holding the umbrella, said:" so little rain, will scare you, quickly, come on!" said mother squat body, wait for me, i hesitate to say:" mom, don't get me," because i know that, mom's leg was not good, but the day before yesterday just had a cold, my mother said with a smile:" are you afraid of her mother to carry you?" i laughed, resigned over mother strong back, rain hit the ground, they have numerous blisters, i hold up the umbrella, tightly over the mother's back, mother in the rain with a deep, shallow kick to move forward, she said:" umbrella the next play, or wet your back." i cried, i cannot find the words to describe the feelings at the time, the very next day, mother's illness, but she said happily:" you did not catch a cold!"

i know, our happiness is the smile on your face, our pain is your eyes deep sorrow. we can go far, far away, but never go out of your mind the square, what affects my soul, always inspire me is your sincere and selfless love, you are like the world all mothers love their children. i wish to be a cup of tea, you thirsty, let you drink, i would like to turn into a breeze, blowing your because of the work and sweat, but, i am not, i can only give you every end of herbal tea, give you fan. can you forgive me?

now i know: thanksgiving, is the heart and the heart of the impact, which can burst out of the spark of love, i sincerely hope that all children have a thankful heart.

你好,每个人。

爸爸,妈妈是一个很善良,慈爱的母爱,包含无限动人的词。在这个世界上,只有妈妈对孩子的爱是最真挚,最无私的。然而,父母知道爱,父母知道奉献,为什么我们不能有一颗感恩的心吗?因此,我今天演讲的主题是感恩的心。

感恩是一种美德,是一个历史悠久的文化遗产。其来源就像爱的流水。历史的记忆,我们感动一个母亲对儿子的故事:古代,可以成为大产业,三个动作,为后人留下告诉的故事。在现代,一个著名的抗日马将军jingzhai年代的母亲,她被逮捕,面对日本人的威胁,没有恐惧,决定让她的儿子到抗日战争,然后迅速死亡。马jingzhai写道伟大的母亲,生活在精神上,轴承的儿子的母亲,继续斗争。。这一个案例中,一个爱的赞美诗,不能反映一个母亲伟大吗?

我的母亲是一个平凡的,但她在一个轻松的早晨给了我生命,她是横向斜雨中在路上的生活,给我力量,在我挫折,她给了我自信,自豪地和她,在我被大当我卑微的教堂。从心底里感谢她多年来,尽管失去了她的青春和美丽,但她在我心中永远是丘比特,阿佛洛狄忒。困难虽然把她美丽的歌声,但她的每一个字我的心金严韵,这是自己的行为告诉我的母亲最常见的一种意义:爱是无私奉献。

记得夏天的早上,雨下得很大,我说:我的母亲,雨太大,不去上学,她说,拿着雨伞,说:这么少雨,会吓到你,很快,加油!母亲说蹲下身体,等待我,我犹豫地说:妈妈,别让我,因为我知道,妈妈的腿不太好,但前天感冒了,妈妈笑着说:你害怕她母亲带你吗?我笑了,辞职的母亲强回来,雨落到地面,他们有大量的水泡,我拿着雨伞,紧紧地在妈妈的背上,妈妈在雨中深、浅踢前进,她说:把伞下玩耍,或湿你的背部。我哭了,我找不到词来形容当时的感觉,就在第二天,母亲的病,但她高兴地说:你没有感冒!

我知道,我们的幸福是你脸上的微笑,我们的痛苦是你的眼睛深深的悲伤。我们可以去很远很远的地方,但从来没有走出你的头脑广场,什么影响我的灵魂,总是激励着我是你的真诚和无私的爱,你就像世界上所有的母亲都爱自己的孩子。我想要一杯茶,你渴了,让你喝,我想变成一个微风,吹你因为工作和汗水,但我不是,我只能给你每一个草药茶,给你的粉丝。你能原谅我吗?

现在我知道:感恩节,是心脏和心脏的影响,可以爆发出爱的火花,我衷心希望所有的孩子都有一颗感恩的心。

演讲稿大全字篇4

尊敬的各位领导，亲爱的各位同仁们:

大家好！

今天我演讲的题目是《以无私之吾辈，成泱泱之大国》。方圆九州，泱泱大国，五千年的历史文化浩如烟海。中华儿女，用自己的勤劳和智慧，缔造了强汉盛唐，领世界风骚几千年，何等风光!直到鸦片战争爆发，洋枪火炮轰开了国门，中国沦为半殖民地半封建社会。各帝国列强肆虐神州大地，国家蒙难，前路茫茫，中华民族处于水深火热之中。是中国共产党成立于乱世之时，担负起了复兴中华之使命。2021年是中国共产党的百年华诞，百年前，中国山河破碎，国弊民穷；百年后，中国山河无恙，国泰民安。

忆往昔，红色基因，力挽狂澜。1921年7月，浙江嘉兴南湖的一艘红船上传出巨人的呐喊，犹如春雷唤醒了沉睡已久的东方雄狮，拨开了数百年来笼罩于千万仁人志士心头的迷雾，亮出了共产主义的伟大旗帜，点燃了神州大地上的星星革命之火。从此，炎黄子孙们有了值得付托的领导人。党照亮了黎明前的黑暗，指引着前进的方向。

回首眺望过去的历程，却是那样的曲折不平凡，你看那洒满鲜血的路上，一个个脚印记载着多少风雨与沧桑。从艰苦卓绝的井冈山斗争到千难万险的长征路，从硝烟弥漫的抗日战争到摧枯拉朽的的解放战争，无数先烈抛头颅洒热血，前仆后继，进行艰苦卓绝的斗争，才赢得了国家的独立、人民的解放和中国的强盛。

看今朝，风雨兼程，初心未改。去年的新冠疫情严峻，中国顶住了压力，用行动证明了大国风范，让世界为之惊叹。而在这背后，是许许多多勇敢的中国人以生命负生命，用挚爱守护苍生，每当危难时刻总会有英雄挺身而出，这是中华民族伟大精神的体现，中国人民以敢于斗争、敢于胜利的大无畏气概，铸就了生命至上,举国同心、舍生往死、尊重科学、命运与共的伟大抗疫精神。

作为一名普通而又神圣的教师，我们深深的懂得，要继承和发扬这些先辈们的先锋精神，衷心热爱自己的职业。耿耿园丁意，拳拳育人心；身于幽谷处，孕育兰花香。让我们发起青春的誓言:任凭岁月更迭，世事沧桑，任凭青春流逝，红颜憔悴，我会永守心中这盏希望之灯，不断努力。树万世之师表，铸不朽之师魂！

演讲稿大全字篇5

亲爱的老师，同学们：

大家好！我是__班学生__，我演讲的题目是《壮我中华》。

当2008年北京奥运圣火点燃，13亿中国人引以为豪的瞬间；当2010年上海世博会盛大开幕，全世界爱好和平的人士都为之赞叹；当舟曲泥石流肆虐成灾，子弟兵奋不顾身英勇救援；当嫦娥奔月神七飞天，千年梦想一朝实现；亲爱的同学们，你是否感受到民族复兴的车轮滚滚向前，你是否感受到中华振兴的航船正在扬帆？

作为一个中国人，78年改革开放的伟大成就，我们都能感受，我们都为之自豪。

但是，你可曾想到，共和国前进的道路并非鲜花遍地，而是荆棘丛生，暗流涌动。

同学们，这些年，我们虽然取得了巨大成就，但是和发达国家相比，还有很大的差距。这也是那些反华势力之所以敢于明目张胆地挑衅的根源所在。同学们，作为一个中国人，未来的建设者，我们应该怎样做呢？

我们要有强烈的历史责任感，牢记“生于忧患，死于安乐”的古训，忘我学习，顽强拼搏，苦练本领，为中国的强盛而奋斗。同学们，来，让我们一起宣誓：“兴我民族，强我国家，血荐轩辕，壮我中华”。

演讲稿大全字篇6

同学们：

你们好!今天我的演讲的内容是有关环保的。