UOI Group by Michelle

michellemayixin — 2019-02-19 10:13:56 UTC

Hi! someone is here ?

elainetan_sh — 2019-02-19 13:47:25 UTC

Hi! I am finally in!

elainetan_sh — 2019-02-21 09:51:22 UTC

Hi, is there anyone?

elainetan_sh — 2019-02-21 11:26:57 UTC

 Acid Rain

Acid rain, also called acid precipitation or acid deposition, precipitation possessing a pH of about 5.2 or below primarily produced from the emission of sulfur dioxide (SO₂) and nitrogen oxides (NO; the combination of NO and NO₂) from human activities, mostly the combustion of fossil fuels. In acid-sensitive landscapes, acid deposition can reduce the pH of surface waters and lower biodiversity. It weakens trees and increases their susceptibility to damage from other stressors, such as drought, extreme cold, and pests. In acid-sensitive areas, acid rain also depletes soil of important plant nutrients and buffers, such as calcium and magnesium, and can release aluminum, bound to soil particles and rock, in its toxic dissolved form. Acid rain contributes to the corrosion of surfaces exposed to air pollution and is responsible for the deterioration of limestone and marble buildings and monuments.

When gases emitted by motor vehicles and industrial processes encounter clouds, the water vapour in the clouds combines with them to form acids, which are then returned to Earth as acid precipitation.

 The Effect of Acid Rain on Human

Acid rain looks, feels, and tastes just like clean rain. The harm to people from acid rain is not direct. Walking in acid rain, or even swimming in an acid lake, is no more dangerous than walking or swimming in clean water. The air pollution that causes acid rain is more damaging to human health. Sulfur dioxide and nitrogen oxides, the major sources of acid rain, can irritate or even damage our lungs.

 The Effects of Acid Rain on Ecosystems

Graph showing level of acidity that is tolerable to various species of aquatic life

This figure illustrates the pH level at which key organisms may be lost as their environment becomes more acidic. Not all fish, shellfish, or the insects that they eat can tolerate the same amount of acid.

An ecosystem is a community of plants, animals and other organisms along with their environment including the air, water and soil. Everything in an ecosystem is connected. If something harms one part of an ecosystem – one species of plant or animal, the soil or the water – it can have an impact on everything else.

 Effects of Acid Rain on Fish and Wildlife

The ecological effects of acid rain are most clearly seen in aquatic environments, such as streams, lakes, and marshes where it can be harmful to fish and other wildlife. As it flows through the soil, acidic rain water can leach aluminum from soil clay particles and then flow into streams and lakes. The more acid that is introduced to the ecosystem, the more aluminum is released.

Some types of plants and animals are able to tolerate acidic waters and moderate amounts of aluminum. Others, however, are acid-sensitive and will be lost as the pH declines. Generally, the young of most species are more sensitive to environmental conditions than adults. At pH 5, most fish eggs cannot hatch. At lower pH levels, some adult fish die. Some acidic lakes have no fish. Even if a species of fish or animal can tolerate moderately acidic water, the animals or plants it eats might not. For example, frogs have a critical pH around 4, but the mayflies they eat are more sensitive and may not survive pH below 5.5.

Effects of Acid Rain on Plants and Trees

Dead or dying trees are a common sight in areas effected by acid rain. Acid rain leaches aluminum from the soil. That aluminum may be harmful to plants as well as animals. Acid rain also removes minerals and nutrients from the soil that trees need to grow.

At high elevations, acidic fog and clouds might strip nutrients from trees’ foliage, leaving them with brown or dead leaves and needles. The trees are then less able to absorb sunlight, which makes them weak and less able to withstand freezing temperatures.

Buffering Capacity

Many forests, streams, and lakes that experience acid rain don’t suffer effects because the soil in those areas can buffer the acid rain by neutralizing the acidity in the rainwater flowing through it. This capacity depends on the thickness and composition of the soil and the type of bedrock underneath it. In areas such as mountainous parts of the Northeast United States, the soil is thin and lacks the ability to adequately neutralize the acid in the rain water. As a result, these areas are particularly vulnerable and the acid and aluminum can accumulate in the soil, streams, or lakes.

Episodic Acidification

Melting snow and heavy rain downpours can result in what is known as episodic acidification. Lakes that do not normally have a high level of acidity may temporarily experience effects of acid rain when the melting snow or downpour brings greater amounts of acidic deposition and the soil can’t buffer it. This short duration of higher acidity (i.e., lower pH) can result in a short-term stress on the ecosystem where a variety of organisms or species may be injured or killed.

Nitrogen Pollution

It’s not just the acidity of acid rain that can cause problems. Acid rain also contains nitrogen, and this can have an impact on some ecosystems. For example, nitrogen pollution in our coastal waters is partially responsible for declining fish and shellfish populations in some areas. In addition to agriculture and wastewater, much of the nitrogen produced by human activity that reaches coastal waters comes from the atmosphere.

Effects of Acid Rain on Materials

Not all acidic deposition is wet. Sometimes dust particles can become acidic as well, and this is called dry deposition. When acid rain and dry acidic particles fall to earth, the nitric and sulfuric acid that make the particles acidic can land on statues, buildings, and other manmade structures, and damage their surfaces. The acidic particles corrode metal and cause paint and stone to deteriorate more quickly. They also dirty the surfaces of buildings and other structures such as monuments.

The consequences of this damage can be costly:

Damaged materials that need to be repaired or replaced,
Increased maintenance costs, and
Loss of detail on stone and metal statues, monuments and tombstones.

elainetan_sh — 2019-02-21 11:29:03 UTC

Actions to Stop Acid Rain: (actions that we can do)

1. Buy Air Cleaning Machine: the acid rain is cause by some air pollution, we can buy Air Cleaning Machine to make the air cleaner

2. Ride More Bikes and Buses: we can ride a bike to decrease the level of tail gas that a car give out, we can also take a bus because a bus can carry a lot of people so we can decrease the level of tail gas too

elainetan_sh — 2019-02-21 11:32:08 UTC

WEBSITES

https://www.britannica.com/science/acid-rain https://www.epa.gov/acidrain/effects-acid-rain http://www2.gsu.edu/~mstnrhx/EnviroBio%20Projects/AcidRain/humans.html

chiaralee — 2019-02-21 13:43:32 UTC

Phew I am finally here

elainetan_sh — 2019-02-21 13:44:41 UTC

Chiara, do you have more actions?

chiaralee — 2019-02-21 13:45:40 UTC

I can think of more I guess wait

chiaralee — 2019-02-21 13:46:36 UTC

chiaralee — 2019-02-21 13:46:50 UTC

Stop using boilers

elainetan_sh — 2019-02-21 13:47:26 UTC

what is a boiler?

elainetan_sh — 2019-02-21 13:47:41 UTC

does it effect the enviorment?

chiaralee — 2019-02-21 13:48:02 UTC

Yes

chiaralee — 2019-02-21 13:48:22 UTC

I think boiler also makes air pollution

chiaralee — 2019-02-21 13:49:20 UTC

Boiler is a kind of machine inside your home’s ground which makes your house warm☺️

elainetan_sh — 2019-02-21 13:50:37 UTC

I never heard of it before

elainetan_sh — 2019-02-21 13:50:51 UTC

Is it like a air conditional?

chiaralee — 2019-02-21 13:51:14 UTC

Oh
Okay 👌
Sorry

elainetan_sh — 2019-02-21 13:51:49 UTC

You don't hve to say sorry

chiaralee — 2019-02-21 13:52:14 UTC

No it is placed on the ground in your house 🏠

chiaralee — 2019-02-21 13:52:57 UTC

I guess now days, most of the people are using boilers

elainetan_sh — 2019-02-21 13:56:59 UTC

...Me too...

2019-02-22 08:52:46 UTC

We have to buy it

2019-02-22 08:56:52 UTC

Hello anyone

michellemayixin — 2019-02-22 09:49:19 UTC

hello

michellemayixin — 2019-02-22 09:49:34 UTC

is anybody here?

michellemayixin — 2019-02-22 09:50:59 UTC

we need to change a topic isn't it

michellemayixin — 2019-02-22 09:51:52 UTC

I need somebody talk to me, we will do what things ?

michellemayixin — 2019-02-22 09:52:10 UTC

Can anyone tell me ?

michellemayixin — 2019-02-22 09:55:30 UTC

please, are you here Elaine, Chiara and Mickey Yang?

michellemayixin — 2019-02-22 09:58:24 UTC

Can we just not change a topic, because I don't know what is our new topic.

michellemayixin — 2019-02-22 09:58:37 UTC

hello

michellemayixin — 2019-02-22 09:58:40 UTC

hello

michellemayixin — 2019-02-22 09:59:28 UTC

hello!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

michellemayixin — 2019-02-22 10:11:35 UTC

we can do 沙漠化

michellemayixin — 2019-02-22 10:12:36 UTC

I don't know the English of it sit was about desert

chiaralee — 2019-02-22 11:28:30 UTC

We already planned a new topic

chiaralee — 2019-02-22 11:34:53 UTC

I guess we were doing something about pollution

michellemayixin — 2019-02-22 11:36:56 UTC

2019-02-22 13:51:10 UTC

I forgot

2019-02-22 13:57:36 UTC

Hey anyone here

2019-02-22 13:57:51 UTC

Or did you guys all got to sleep

2019-02-22 14:01:28 UTC

Answer me please, somebody come on

2019-02-22 14:03:30 UTC

A I have to go to sleep bye-bye

chiaralee — 2019-02-22 14:04:40 UTC

Sorry

chiaralee — 2019-02-22 14:04:55 UTC

I guess I also forgot

chiaralee — 2019-02-22 14:05:16 UTC

Let’s ask Elaine tomorrow

chiaralee — 2019-02-22 14:05:34 UTC

So I mean bye 👋

elainetan_sh — 2019-02-22 14:38:30 UTC

Michelle, do you mean a drought?

elainetan_sh — 2019-02-22 14:38:58 UTC

Sorry, I went out

elainetan_sh — 2019-02-22 14:50:51 UTC

What is a drought?

A drought is when there is a lack of precipitation over an extended period of time, usually a season or more, resulting in a water shortage for some activity, group, or environmental sector. Its impacts result from the interplay between the natural event (less precipitation than expected) and the demand people place on water supply, and human activities can exacerbate the impacts of drought.

What causes a drought?

Drought has many causes. It can be caused by not receiving rain or snow over a period of time. If you live in a place where most of the water you use comes from a river, a drought in your area can be caused by places upstream from you not receiving enough moisture. There would be less water in the river for you and other people who live along the river to use. People can also play a big role in drought. If we use too much water during times of normal rainfall, we might not have enough water when a drought happens.

Can scientists predict if a drought is going to happen?

No! Studies conducted over the past century have shown that meteorological drought is never the result of a single cause. It is the result of many causes including, global weather patterns, high pressure, the tropical outlook and other global-scale variables.

Are there places in the United States that experience drought?

Yes! The Western United States is experiencing an exceptional and extreme drought at this time. To see the map, Click Here to see the current U.S. Drought Monitor.

What was the Dust Bowl?

Of all the droughts that have occurred in the United States, the drought events of the 1930s are widely considered to be the “drought of record” for the nation. The 1930s drought is often referred to as if it were one episode, but it was actually several distinct events occurring in such rapid succession that affected regions were not able to recover adequately before another drought began. The term Dust Bowl was coined in 1935 to describe the drought-affected south central United States in the aftermath of horrific dust storms. Although it technically refers to the western third of Kansas, southeastern Colorado, the Oklahoma Panhandle, the northern two-thirds of the Texas Panhandle, and northeastern New Mexico, the Dust Bowl has come to symbolize the hardships of the entire nation during the 1930s.

How bad was the drought in the Dust Bowl years?

In the 1930s, drought covered virtually the entire Plains for almost a decade. The drought’s direct effect is most often remembered as agricultural. Many crops were damaged by deficient rainfall, high temperatures, and high winds, as well as insect infestations and dust storms that accompanied these conditions. The resulting agricultural depression contributed to the Great Depression’s bank closures, business losses, increased unemployment, and other physical and emotional hardships. Although records focus on other problems, the lack of precipitation would also have affected wildlife and plant life, and would have created water shortages for domestic needs.

What was the Black Sunday Dust Storm?

The 1930s were times of tremendous hardship on the Great Plains. Settlers dealt not only with the Great Depression, but also with years of drought that plunged an already-suffering society into an onslaught of relentless dust storms for days and months on end. They were known as dirt storms, sand storms, black blizzards, and “dusters.” It seemed as if it could get no worse, but on Sunday, the 14th of April 1935, it got worse. The day is known in history as “Black Sunday,” when a mountain of blackness swept across the High Plains and instantly turned a warm, sunny afternoon into a horrible blackness that was darker than the darkest night. Famous songs were written about it, and on the following day, the world would hear the region referred to for the first time as “The Dust Bowl.”

How does a drought affect our lives?

Drought affects our lives in many different ways because water is such an important part of so many of our activities. We need water to live, and animals and plants do too. We need water to grow the food we eat. We also use water for many different things in our lives, like washing dishes, cooking, bathing, and swimming or river rafting. Water is also used to help make the electricity we use to run the lights in our houses and the video games you may like to play. When we don’t have enough water for these activities because of a drought, many people and many different things will be affected in many different ways.

How can we help if we’re in a drought?

One of the easiest steps we can take to help mitigate the impacts of drought is conserving water. If we use water wisely at all times, more water will be available to us and to plants and wildlife when a drought happens. We can lose a lot of water doing simple everyday tasks. Did you know that turning off the water while you brush your teeth can save more than 100 gallons of water a month? If you have a leaky faucet, the drips can add up to 300 gallons of wasted water a month.

elainetan_sh — 2019-02-22 14:51:05 UTC

http://www.weatherwizkids.com/?page_id=89

elainetan_sh — 2019-02-22 14:52:25 UTC

干旱是什么?

夏季是当有呜呼沉淀一段时间,通常一个赛季甚至更多,导致水资源短缺对一些活动,组织,或环保部门。间相互作用的结果,其影响自然事件(降水比预期少)和人们对水的需求供应,和人类活动会加剧干旱的影响。

导致干旱的原因是什么?

干旱的原因有很多。可能是由于不接受在一段时间内的降雨或降雪。如果你住在一个地方,大部分您所使用的水来自河流,你所在地区的干旱可能是由于上游的地方你没有得到足够的水分。对你会有更少的水在河里和其他沿河居民使用。人们可以在干旱也扮演着重要的角色。如果我们使用太多的水在正常降雨,我们可能没有足够的水当发生干旱。

科学家预测如果干旱会发生什么?

不!研究在过去的一个世纪已经表明,气象干旱从来都不是单一原因的结果。这是很多原因的结果,包括全球气候模式,高压、热带前景和其他全球范围内变量。

有在美国经历干旱的地方?

是的!美国西部正在经历一个特殊和极端干旱。看地图,点击这里查看当前美国干旱监测。

沙尘暴是什么?

所有的干旱发生在美国,1930年代的干旱事件被广泛认为是“创纪录的干旱”的国家。1930年代的干旱通常被称为如果其中一集,但它实际上是几个不同的事件发生在如此快速的连续影响地区另一个干旱开始之前未能充分恢复。沙尘暴在1935年创造了这个词来形容美国遭受干旱影响中南部后可怕的沙尘暴。虽然从技术上讲是指西部第三的堪萨斯州,科罗拉多东南部,俄克拉荷马狭长地带,北部三分之二的德州狭长地带,新墨西哥东北部,沙尘暴来象征着苦难的整个国家在1930年代。

多么糟糕的干旱尘暴年?

在1930年代,干旱覆盖几乎整个平原差不多有十年了。干旱的直接影响是最常想起农业。许多农作物受损缺乏降雨,高温、大风、虫害和沙尘暴,这些条件。导致农业萧条导致了大萧条的银行倒闭,企业损失,增加失业和其他生理和情感上的困难。尽管记录关��其他问题,缺乏降水也会影响野生动物和植物的生命,并为国内需求创造了水资源短缺。

黑色星期天的沙尘暴是什么?

1930年代*大平原上的巨大困难。移民不仅处理大萧条时期,但也有多年的干旱已经遭受社会陷入无情的冲击的沙尘暴几天,几个月。他们被称作污垢风暴、沙尘暴、黑色暴风雪,和“抹布。”似乎没有得到更糟糕的是,但在周日,1935年4月14日,情况更糟了。一天在历史上被称为“黑色星期天”,当堆积如山的黑暗横扫平原和高立刻变成一个温暖,晴朗的下午到一个可怕的黑暗,是最黑暗的夜晚。著名歌曲写,第二天,世界将首次听到该地区称为“沙尘暴”。

干旱是如何影响我们的生活?

干旱影响等许多不同的方式,因为水是我们生活的重要组成部分,所以我们的许多活动。我们生活需要水,动物和植物也是。我们需要水来增长我们所吃的食物。我们也使用水做很多不同的事情在我们的生活中,像洗碗、做饭、洗澡、游泳或者漂流。水还用于帮助我们使用的电力运行灯在我们的房子,你可能会喜欢的游戏去玩。当我们没有足够的水,这些活动,因为干旱,许多人,许多不同的东西在许多不同的方式将受到影响。

我们怎样才能帮助如果我们在干旱吗?

我们可以采取最简单的步骤来帮助减轻干旱保护水的影响。如果我们明智地使用水,更多的水对植物和野生动物将提供给我们,当发生干旱。我们可以失去很多水做简单的日常任务。你知道关掉水刷牙的时候可以节省超过100加仑的水一个月?如果你有一个漏水的水龙头,滴下可以添加多达300加仑的水浪费了一个月。

elainetan_sh — 2019-02-23 01:52:34 UTC

Hello?

elainetan_sh — 2019-02-23 01:52:41 UTC

Is there anyone?

2019-02-23 04:08:12 UTC

Sorry I slept in till 11:00

mickey13661966807 — 2019-02-23 04:13:31 UTC

mickey13661966807 — 2019-02-23 04:14:16 UTC

笑点很低？在吗

elainetan_sh — 2019-02-23 12:12:24 UTC

If you guys don't answer me in the last 10 minutes, I am going to tell Ms. Aish that drought is our topic

mickey13661966807 — 2019-02-24 04:59:37 UTC

mickey13661966807 — 2019-02-24 05:02:44 UTC

Someone there

michellemayixin — 2019-02-24 05:28:52 UTC

hello

michellemayixin — 2019-02-24 05:33:20 UTC

is there any body

michellemayixin — 2019-02-24 05:33:49 UTC

here??????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????

elainetan_sh — 2019-02-24 05:45:50 UTC

Guys, do we have actions to stop the drought?

elainetan_sh — 2019-02-24 05:46:04 UTC

Don't waste water?

michellemayixin — 2019-02-24 05:47:00 UTC

maybe the drought

michellemayixin — 2019-02-24 05:47:32 UTC

沙漠化

michellemayixin — 2019-02-24 05:49:00 UTC

实际上，土地沙漠化（又称土地荒漠化）是全球性的环境问题，同时也是地球上所有居民面临的十大生态环境问题之一。因此我们应该从日常生活的点滴做起，防止沙漠化。
荒漠化的扩展，沙尘暴的肆虐，最根本的原因是生态系统出现了故障。在治理荒漠化的同时，我们更应该做好预防措施，做到防治结合、标本兼治。
  防是治本之道，主要指防止人类活动产生的负面环境效应。因此，我们必须整合全社会的力量，合理利用各个地方的资源，建立适宜的生产结构。而治是应急之路，主要指通过一些工程手段，对已经荒漠化的土地进行重建和修复。
防治土地荒漠化是国家的一项重要决策，政府不断加强防治荒漠化的法律体系，建立有效的法律保障体系。
  同时，也必须组织广大群众防沙治沙，做到有规划、有步骤、求规模、求效益，加速治理荒漠化土地，坚持做到经济建设和环境建设同步规划、同步实施、同步发展。治理荒漠化时应考虑加强多学科合作研究，运用多学科知识实施防治结合政策。根据各个地方的特点，因地制宜做好规划工作，加强理论研究和实际工作的结合，应用高新技术，发挥科技人员的作用，重视防沙的科研和推广工作。
  此外，也应广泛开展宣传工作，提高公众防治荒漠化的意识，动员全社会力量广泛参与到相关工作中。

michellemayixin — 2019-02-24 05:49:38 UTC

蚂蚁森林在做这种事情

elainetan_sh — 2019-02-24 05:49:52 UTC

Indoors:

Check faucets and pipes for leaks
Dishwashers typically use less water than washing dishes by hand
Run the dishwasher only when full to save water and energy
Install low-flow showerheads and save 2.5-15 gallons of water during a 10-minute shower
Take five-minute showers instead of 10-minute showers and save 12.5-25 gallons of water
Nearly 22 percent of indoor home water use comes from doing laundry, save water by using it for full loads only
Turn water off when brushing teeth to save approximately 10 gallons a day
Turn water off while washing your hair and save up to 150 gallons a month
Plug the sink instead of running the water to rinse your razor and save up to 300 gallons a month
When washing your hands, turn the water off while you lather
Buy water-saving devices like high-efficiency toilets and clothes washers
Install aerators on the kitchen faucet to reduce flows to less than 1 gallon per minute

elainetan_sh — 2019-02-24 05:50:24 UTC

Cutting down on personal water use:

Outdoors: Most water is used outside of the home—mainly to irrigate landscaping. Nearly 60 percent of a person’s household water footprint can go toward lawn and garden maintenance.

Water early in the morning or later in the evening when temperatures are cooler and save 25 gallons each time you water
Use a broom instead of a hose to clean driveways and sidewalks
Garden with native species
Don't just landscape, xeriscape:

Xeriscape gardening methods can reduce your water usage by up to 40 percent. To xeriscape, practice the following:

Use mulch to reduce evaporation
Till your soil so it absorbs more water
Use turf sparingly and only when necessary
Choose native plants that use less water
Raise the height of your lawnmower

elainetan_sh — 2019-02-24 05:50:37 UTC

Protecting our water future

We all need to do our part to solve the drought—from saving water by changing our personal habits, to advocating for water efficiency reforms statewide.

We also need to promote the most practical solutions to global warming, so this megadrought doesn't become the new normal. That's why Environment California is promoting cleaner cars and clean energy—solutions that clean up our air and save water. And this drought is just another big reason why we need to ban fracking statewide. Fracking is a dirty form of drilling that not only turns landscapes into industrial zones, but it also uses million of gallons of water we just can't spare.

michellemayixin — 2019-02-24 05:51:54 UTC

OK'

michellemayixin — 2019-02-24 05:52:26 UTC

I need to go to the class bye

elainetan_sh — 2019-02-24 05:52:47 UTC

I'll send the action to Ms. Aish

elainetan_sh — 2019-02-24 05:52:48 UTC

Byr

chiaralee — 2019-02-24 12:54:43 UTC

Sorry I was out

chiaralee — 2019-02-24 12:55:10 UTC

So do you mean our topic is drought??

chiaralee — 2019-02-24 12:55:16 UTC

Okay

chiaralee — 2019-02-24 12:55:22 UTC

Bye

michellemayixin — 2019-02-25 11:15:41 UTC

mickey13661966807 — 2019-02-25 12:38:03 UTC

michellemayixin — 2019-02-25 12:39:25 UTC

干旱是对人类社会影响最严重的气候灾害之一，它具有出现频率高、持续时间长、波及范围广的特点。干旱的频繁发生和长期持续，不但会给社会经济，特别是农业生产带来巨大的损失，还会造成水资源短缺、荒漠化加剧、沙尘暴频发等诸多生态和环境方面的不利影响。我国1949到2006年平均每年受旱面积2122万公顷，约占各种气象灾害受灾面积的60％。可造成以下几大方面的危害：

（一）干旱是危害农牧业生产的第一灾害

气象条件影响作物的分布、生长发育、产量及品质的形成，而水分条件是决定农业发展类型的主要条件。干旱由于其发生频率高、持续时间长，影响范围广、后延影响大，成为影响我国农业生产最严重的气象灾害；干旱是我国主要畜牧气象灾害，主要表现在影响牧草、畜产品和加剧草场退化和沙漠化。

干旱对作物危害程度与其发生的季节、作物的种类、品种、生育期有关。春季干旱影响春播，或造成春播作物缺苗断垄并影响越冬作物的正常生长。

7~8月份的伏旱，在中国北方影响玉米、高粱、水稻的正常生长，造成棉花的蕾铃脱落。在南方影响早、中稻的正常灌浆和晚稻的移栽成活。

秋旱影响秋作物的产量及越冬作物的播种。伏旱和秋旱都会使土壤的底墒不足而加剧翌年的春旱。

作物对干旱的抵抗能力称为抗旱性，不同作物的抗旱性不同，水稻的抗旱性最差，遇干旱无灌溉的条件时减产严重，陆稻其次，大麦、小麦、黑麦、燕麦、花生等作物抗旱性中等，糜子、高粱、胡流、粟、马铃薯、甘薯、绿豆等作物抗旱性较强。

作物对不同类型干旱的反应是不同的，例如一些豆科作物根系发达，抗土壤干旱的能力强，但不能忍受大气干旱；玉米抗大气干旱能力强而不能忍受土壤干旱。我国发生干旱最严重的地区是甘肃中部、宁夏南部、山西和陕西北部、内蒙古自治区的中西部以及河北省坝上地区等。防御干旱主要靠发展水利灌溉事业、植树造林、改革农业结构、改进耕作制。度以及加强农田基本建设等。

（二）干旱促使生态环境进一步恶化

1、气候暖干化造成湖泊、河流水位下降，部分干涸和断流。由于干旱缺水造成地表水源补给不足，只能依靠大量超采地下水来维持居民生活和工农业发展，然而超采地下水又导致了地下水位下降、漏斗区面积扩大、地面沉降、海水入侵等一系列的生态环境问题。

2、干旱导致草场植被退化。我国大部分地区处于干旱半干旱和亚湿润的生态脆弱地带，气候特点为夏季盛行东南季风，雨热同季，降水主要发生在每年的4-9月。北方地区雨季虽然也是每年的4-9月，但存在着很大的空间异质性，有十年九旱的特点。由于气候环境的变迁和不合理的人为干扰活动，导致了植被严重退化，进入21世纪以后，连续几年，干旱有加重的趋势，而且是春夏秋连旱，对脆弱生态系统非常不利。

3、气候干旱加剧土地荒漠化进程

（三）气候暖干化引发其他自然灾害发生

冬春季的干旱易引发森林火灾和草原火灾。自2000年以来，由于全球气温的不断升高，导致北方地区气候偏旱，林地地温偏高，草地枯草期长，森林地下火和草原火灾有增长的趋势。

michellemayixin — 2019-02-25 12:42:39 UTC

http://youth.wmo.int/zh/met-subpages/%E8%8D%92%E6%BC%A0%E5%8C%96#tab4

mickey13661966807 — 2019-02-25 12:56:57 UTC

you there

mickey13661966807 — 2019-02-25 13:22:10 UTC

see you tommorow

chiaralee — 2019-02-26 12:32:05 UTC

chiaralee — 2019-02-26 12:32:58 UTC

We need to talk at 8:30 right???

chiaralee — 2019-02-26 12:34:11 UTC

Is there anybody right now??

chiaralee — 2019-02-26 12:34:21 UTC

We have to plan

chiaralee — 2019-02-26 12:34:53 UTC

Is there anybody I could talk to???

chiaralee — 2019-02-26 12:35:31 UTC

I could tell you guys the roots and shoots website

chiaralee — 2019-02-26 12:35:37 UTC

Wait

chiaralee — 2019-02-26 12:36:21 UTC

Here you are

chiaralee — 2019-02-26 12:36:51 UTC

http://srschina.org/en/

chiaralee — 2019-02-26 12:38:05 UTC

So can I contact the Roots and Shoots because there are nobody I could talk to

chiaralee — 2019-02-26 12:38:22 UTC

Can I or...

chiaralee — 2019-02-26 12:40:54 UTC

Sorry but I think there are no time for sending the email to Roots and Shoots together because Ms Aish said we can't bring the devices execpt the last day of our project

chiaralee — 2019-02-26 12:41:02 UTC

Hello

chiaralee — 2019-02-26 12:41:43 UTC

Can you guys pls reply

chiaralee — 2019-02-26 12:41:48 UTC

Please

michellemayixin — 2019-02-26 22:56:07 UTC

hello

michellemayixin — 2019-02-27 09:37:27 UTC

Hello

michellemayixin — 2019-02-27 09:37:40 UTC

Anybody here

chiaralee — 2019-02-27 09:43:01 UTC

chiaralee — 2019-02-27 09:43:17 UTC

I am here

michellemayixin — 2019-02-27 09:43:29 UTC

michellemayixin — 2019-02-27 09:44:08 UTC

what we will do in this weeklend will we go out

chiaralee — 2019-02-27 09:49:35 UTC

We need to ask our parents first

michellemayixin — 2019-02-27 09:49:49 UTC

chiaralee — 2019-02-27 09:50:10 UTC

Or else we can’t go MS AISH said

michellemayixin — 2019-02-27 11:02:27 UTC

Did you contact with Roots and shoot yesterday @Chiara?

mickey13661966807 — 2019-02-28 09:30:36 UTC

mickey13661966807 — 2019-02-28 09:41:20 UTC

Anyone there

mickey13661966807 — 2019-02-28 09:41:47 UTC

My mom agreed to send me

mickey13661966807 — 2019-02-28 09:51:03 UTC

To the subway station

mickey13661966807 — 2019-02-28 09:53:30 UTC

Anyone one is ok as long as there is someone

mickey13661966807 — 2019-02-28 09:54:55 UTC

Hello

mickey13661966807 — 2019-02-28 09:59:35 UTC

If you see this send me a email and tell me if you are going or not

mickey13661966807 — 2019-02-28 09:59:52 UTC

Bye

chiaralee — 2019-02-28 10:19:31 UTC

I am not sure so I will ask my mom right now

chiaralee — 2019-02-28 10:20:11 UTC

But when are we going?????

chiaralee — 2019-02-28 10:20:35 UTC

I need the date first

chiaralee — 2019-02-28 10:20:54 UTC

Mickey YANG???

chiaralee — 2019-02-28 10:21:11 UTC

chiaralee — 2019-02-28 10:21:21 UTC

Pls

michellemayixin — 2019-02-28 10:27:28 UTC

michellemayixin — 2019-02-28 10:27:51 UTC

Is anybody here?

michellemayixin — 2019-02-28 10:28:23 UTC

MY, Chiara and Elain

mickey13661966807 — 2019-03-01 09:15:37 UTC

Michelle!!!!!!!!!!!!!!

michellemayixin — 2019-03-01 10:09:21 UTC

Sorry am here now

michellemayixin — 2019-03-02 04:50:31 UTC

Hello

michellemayixin — 2019-03-02 04:50:47 UTC

Is there any body here

michellemayixin — 2019-03-02 05:01:44 UTC

My mother agree that I can go

mickey13661966807 — 2019-03-03 03:22:39 UTC

mickey13661966807 — 2019-03-03 03:31:11 UTC

Elaine ,Chiara you there

mickey13661966807 — 2019-03-03 03:34:45 UTC

Anyone

mickey13661966807 — 2019-03-03 03:34:53 UTC

Here

mickey13661966807 — 2019-03-03 03:36:10 UTC

mickey13661966807 — 2019-03-03 03:37:10 UTC

Please tell me if you can go

mickey13661966807 — 2019-03-03 03:47:32 UTC

If you see it then please tell me if you can go or not

mickey13661966807 — 2019-03-03 03:55:59 UTC

bye

elainetan_sh — 2019-03-04 11:05:25 UTC

My mom said that I can go

chiaralee — 2019-03-06 13:16:32 UTC

chiaralee — 2019-03-06 13:16:54 UTC

did you showed the permission???

chiaralee — 2019-03-06 13:17:22 UTC

to ms aish?

chiaralee — 2019-03-06 13:17:35 UTC

is there any body here?

chiaralee — 2019-03-06 13:17:43 UTC

please