海洋中塑料论文英语翻译综述
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为什么海洋污染越来越严重英语作文英语作文:English Version:Why is Marine Pollution Becoming Increasingly Severe?In recent decades, the issue of marine pollution has garnered significant attention, as it poses a growing threat to the health of our oceans and the biodiversity they sustain. The reasons for this ever-escalating concern are manifold and range from industrial waste discharge,塑料pollution, overfishing, to climate change.Industrial waste discharge remains a significant contributor to marine pollution. Factories and manufacturing plants often release toxic chemicals and untreated waste into nearby water bodies, eventually draining into the oceans. These pollutants can cause long-term damage to marine ecosystems, affecting both plant and animal life.The ubiquitous presence of plastic in our daily lives has led to a significant increase in plastic pollution in our oceans. Single-use plastics, such as bags, bottles, and straws, often find their way into the sea, either through landfills that leak into groundwater or through direct littering. These plastics can choke marine life, disrupt food chains, and cause long-term damage to the ecological balance.Overfishing has depleted many marine species to the brink of extinction,.This practice not only leads to the depletion of fish stocks but also disrupts the food chain, affecting predator species that depend on them for survival.Climate change is another significant factor driving marine pollution. Rising sea levels, changing weather patterns, and ocean acidification are all having a profoundimpact on the health of our oceans. These changes can lead to coral bleaching, altered fish migrations, and decreased biodiversity.The increasing severity of marine pollution is a result of a combination of industrial waste discharge, plastic pollution, overfishing, and climate change. To address this issue, we need to take urgent action to reduce our carbon footprint, reduce plastic usage, enforce sustainable fishing practices, and improve waste management systems. Only through collective effort and commitment can we ensure the health and sustainability of our oceans for future generations.中文翻译:为什么海洋污染越来越严重?近几十年来,海洋污染问题备受关注,因为它对我们的海洋健康及其维持的生物多样性构成了越来越大的威胁。
海洋塑料排放英文作文英文回答:Plastic pollution in our oceans is a serious environmental problem that threatens marine life, damages ecosystems, and affects human health. Every year, millions of tons of plastic enter the ocean, either directly from coastal sources or indirectly through rivers and waterways. This plastic can take hundreds of years to decompose, andit can accumulate in the environment, harming wildlife and disrupting food chains.Marine animals, such as sea turtles, whales, and dolphins, are particularly vulnerable to plastic pollution. They can ingest plastic bags and other items, mistaking them for food. This can lead to blockages in theirdigestive systems, starvation, and even death. Plastic can also entangle marine animals, restricting their movement and making them more vulnerable to predators.In addition to its direct impacts on marine life,plastic pollution can also damage marine ecosystems. Coral reefs, for example, are sensitive to plastic pollution, which can smother corals and block sunlight from reaching them. This can lead to the decline of coral reefs, whichare important habitats for a variety of marine species.Plastic pollution also affects human health. Microplastics, which are small pieces of plastic less than5 millimeters in size, can be ingested by humans through seafood and drinking water. Microplastics can contain harmful chemicals that can accumulate in the body over time, leading to a variety of health problems.To address the problem of plastic pollution in our oceans, it is important to reduce the amount of plasticthat enters the environment. This can be done by reducing our consumption of plastics, recycling plastics whenever possible, and properly disposing of plastics. We also needto invest in research and development of new materials that are biodegradable or compostable.By working together, we can reduce plastic pollution in our oceans and protect marine life, ecosystems, and human health.中文回答:海洋塑料垃圾是一个严重的环境问题,它威胁着海洋生物,破坏生态系统,并影响人类健康。
塑料袋环保作文英语带翻译Title: The Environmental Impact of Plastic Bags。
Plastic bags have become an indispensable part of our daily lives, but their widespread use comes at asignificant cost to the environment. In this essay, we will delve into the environmental impact of plastic bags and explore potential solutions to mitigate their harmful effects.First and foremost, plastic bags pose a serious threat to wildlife. When not properly disposed of, these bags often end up in natural habitats such as oceans, rivers, and forests. Marine animals, in particular, are highly vulnerable to plastic pollution. Many sea creatures mistake plastic bags for food and ingest them, leading tointestinal blockages, starvation, and ultimately death. Additionally, birds and land animals can become entangled in plastic bags, resulting in injury or suffocation.Furthermore, the production of plastic bags contributes to the depletion of finite resources and exacerbates climate change. Plastic is derived from non-renewablefossil fuels such as oil and natural gas. The extraction and processing of these resources emit greenhouse gases, which contribute to global warming and climate instability. Moreover, the manufacturing process itself consumes vast amounts of energy and water, further straining the environment.In addition to their environmental impact, plastic bags also have economic implications. Municipalities spend millions of dollars each year on litter clean-up and waste management, much of which is attributable to plastic bags. Moreover, the tourism industry suffers when natural landscapes are marred by litter, deterring visitors and diminishing revenue.To address these challenges, several strategies can be implemented. Firstly, governments can enact legislation to restrict or ban the use of single-use plastic bags. Several countries and municipalities have already implemented suchmeasures, resulting in significant reductions in plastic pollution. Additionally, consumers can adopt eco-friendly alternatives such as reusable cloth bags or biodegradable bags made from plant-based materials. By making conscious choices at the individual level, we can collectively reduce our reliance on plastic bags and lessen their environmental impact.Education and awareness also play a crucial role in combating plastic pollution. By educating the public about the environmental consequences of plastic bags and promoting sustainable alternatives, we can foster a culture of environmental stewardship and responsible consumption. Schools, community organizations, and businesses can all play a role in raising awareness and promoting behavior change.In conclusion, plastic bags pose a significant threat to the environment, wildlife, and human health. However, by implementing legislative measures, adopting eco-friendly alternatives, and raising awareness, we can mitigate the harmful effects of plastic bags and move towards a moresustainable future.标题,塑料袋对环境的影响。
这很重要英语作文海洋垃圾英文回答:Marine pollution from plastic waste is a global issue that has become increasingly pressing in recent years. Plastic waste accumulates in our oceans, breaking down into microplastics that are ingested by marine life and enterthe human food chain. The consequences of marine pollution are far-reaching and include damage to marine ecosystems, loss of biodiversity, and potential health risks for humans.To address the problem of marine pollution, it iscrucial to reduce the amount of plastic waste produced andto improve waste management practices. This can be achieved through a combination of policy measures, technological innovation, and consumer awareness.Policy measures can play a significant role in reducing the consumption of single-use plastics and promoting more sustainable alternatives. For example, governments canimpose taxes on plastic bags, ban the use of certainsingle-use plastics, and set targets for the reduction of plastic waste.Technological innovation is also essential for developing more sustainable plastic products and waste management systems. This includes research into new materials that are biodegradable or compostable, as well as the development of more efficient recycling technologies.Consumer awareness is vital for changing behaviors and encouraging individuals to reduce their own plastic consumption. Public education campaigns can raise awareness about the environmental impact of plastic pollution and provide tips for reducing waste.In addition to these measures, international cooperation is necessary to address the global issue of marine pollution. This includes sharing of knowledge and best practices, as well as the development of global standards for waste management.By implementing these strategies, we can significantly reduce marine pollution and protect our oceans for future generations.中文回答:近年来,来自塑料废弃物的海洋垃圾已成为一个日益严峻的全球性问题。
塑料污染给海洋的带来危害英语作文英文回答:Plastic Pollution Destroys Marine Ecosystems.Plastic pollution is a major threat to marine ecosystems, harming marine life and disrupting the delicate balance of the ocean. This ubiquitous material infiltrates all levels of the food chain, from microscopic plankton to large marine mammals.Ingestion and Starvation.Marine animals often mistake plastic debris for food, leading to ingestion and starvation. Indigestible plastic accumulates in the animals' digestive tracts, blocking nutrient absorption and causing malnutrition. This can lead to emaciation, reduced growth rates, and even death.Entanglement.Plastic entanglement is another significant hazard to marine life. Animals can become entangled in discarded fishing gear, plastic bags, and other debris, restricting their movement and causing injuries. Entangled animals may struggle to feed, swim, or breathe, leading to prolonged suffering or death.Chemical Leaching.Plastic materials contain a variety of chemical additives and plasticizers that can leach into the marine environment. These chemicals can have toxic effects on marine organisms, disrupting their hormonal balance, reproductive systems, and immune functions.Habitat Degradation.Plastic pollution accumulates in marine habitats, smothering coral reefs, seagrass beds, and other vital ecosystems. This degradation reduces biodiversity, disrupts food chains, and impairs the overall health of the ocean.Ghost Fishing.Abandoned or lost fishing gear made of plastic continues to capture and kill marine life in a process known as "ghost fishing." These nets and traps entangle fish, sea turtles, and other animals, leading to population declines and ecosystem disruption.Plastic Pollution Endangers Human Health.Marine plastic pollution can also pose risks to human health. Microplastics, tiny pieces of plastic less than 5mm in size, are ingested by marine organisms and can accumulate in the food chain, eventually reaching human consumers. These microplastics may contain harmful chemicals that can have adverse effects on human health.Addressing the Plastic Pollution Crisis.Addressing the plastic pollution crisis requires a multifaceted approach that involves reducing plasticproduction, improving waste management, and promoting sustainable alternatives. Governments, industries, and individuals must collaborate to implement effectivesolutions and protect marine ecosystems for future generations.中文回答:塑料污染破坏海洋生态系统。
关于海洋塑料垃圾的问题和建议英语作文关于海洋塑料垃圾的问题和建议英语作文 1Directions:Water pollution is a serious problem threatening the survival of human beings,plants and animals.It is urgent that some strong measures be adopted to deal with the problem.There has been a discussion recently on the issue in a newspaper.Write a letter to the newspaper based on the following outline:1.Present situation2.Suggested measures to be taken3.Future prospectWrite an essay of about 200 words within 40 minutes on the ANSWER SHEET.关于海洋塑料垃圾的问题和建议英语作文 2These days, we discuss about how to protect the environment and built the harmonious society. Many students give us their ways and I think theses ways will be helpful.In my opinion, how to dispose of rubbish is a very important thing. First, rubbish is a great pollutionin city, and how to deal with them has been a big problem .There are many ways such as classify ,collect, sometimes we can buy the rubbish and don’ t forget to deal with the polluted water .Also, the ways ofprovide against the pollution is very important .We should make laws to stop people from throwing away the rubbish and make city more beautiful.Anyway ,the society is ours, the world is ours.All of us should make contributions to protect the environment, protect everything around us. I believe, if everyone an help. we can make a harmonious society in a short time.关于海洋塑料垃圾的问题和建议英语作文 3Protect environment, you and me from the startGarbage divides a lot of kinds such as: food bag, peel, wastepaper, white plastic bags, leaves, leftover residue, various bottles, etc.;The garbage can is divided into, recyclable and unrecyclable recyclable two, are: all kinds of bottles, glass, cardboard, unrecyclable are: food bag, peel, paper scraps, etc..Dad said: "recyclable garbage, recycling use, unrecyclable garbage landfill or incineration, directly, it can reduce the waste of resources, butalso protect environment. I hope you can take good care of our planet关于海洋塑料垃圾的问题和建议英语作文 4With the developement the society,the rubbish are getting more and more.It is harmful to the environment and health.So we must to take some measures to handle this serious problem.According to the report,thounds of tons rubbish were made in a city,and do you know how many cities in China,it will bring us a lot of problems.First,I think the goverement should build some factories to handle the rubbish,and we could divide the rubbish into different parts.Because some of them could be reused.Like iron and glasses.Secondly,as a person.We shoud not throw them everywhere.It is very simple to put the rubbish into the dustin.I believe with the help of the goverement and all the people,our Earth Mother will bee more and more beautiful.Let us do it together.关于海洋塑料垃圾的问题和建议英语作文 5Society produces a lot of rubbish, such asleftover food, waste paper, plastic bottles and batteries every day. It has bee a big headache in every city. How to solve this problem? I think rubbish classification is a good way of dealing with it.Firstly, rubbish classification can reduce the amount of rubbish and the rubbish pollution to the environment. What is more, it can recycle resources, which will do good to our environmental protection.Since rubbish classification has so many advantages, our government should take effective measures and immediate actions. Different dustbins should be placed in public places so that residents can leave their sorted rubbish in them.关于海洋塑料垃圾的问题和建议英语作文 6The Significance of Waste SortingPeople are producing waste every day, which is a huge burden on the planet's habitat.Some waste is not degradable naturally, which will exist forever, but some waste can be recycled and reused again.Waste sorting can help divide the reusable waste from the rest.And there are two reasons for doing this.Firstly, the earth is limited in its natural resources, and many products are made from finite resources, which cannot be generated by nature in a short period of time.Simply dumping this kind of products is wasting resources.Secondly, some part of the waste is of value.To reuse and recycle this kind of waste is to save resources to a large extent, which also contributes to environmental protection.Sorting waste is a meaningful deed. If everyone can do it, small things can make a big positive impact on the environment.。
塑料污染给海洋带来的危害英文作文The Harm of Plastic Pollution to the Ocean.Plastic pollution has become a major threat to the health and well-being of our oceans. It is causing significant harm to marine life and ecosystems, and the consequences are far-reaching. In this essay, I will discuss the dangers of plastic pollution in both English and Chinese.英文回答,Plastic pollution poses a grave threat to the ocean. The sheer volume of plastic waste that ends up in the ocean each year is staggering. It is estimated that 8 million metric tons of plastic enter the ocean annually. This plastic waste is harmful to marine life in several ways.Firstly, marine animals often mistake plastic debrisfor food. Sea turtles, for example, may confuse plastic bags with jellyfish and ingest them. This can lead tointestinal blockages, malnutrition, and even death. Similarly, seabirds often consume small plastic particles, which can accumulate in their stomachs and cause starvation.Secondly, plastic pollution can also entangle marine animals, leading to injury or death. Fishing gear, such as discarded nets and lines, is a major contributor to this problem. Whales, dolphins, and seals are particularly vulnerable to entanglement, which can restrict their movement, cause injuries, and even drown them.Moreover, plastic pollution disrupts marine ecosystems. Coral reefs, for instance, are vital habitats that supporta diverse range of marine species. However, plasticpollution can smother and damage coral reefs, leading to their decline and loss of biodiversity. Additionally, microplastics, which are tiny plastic particles, can contaminate the water and be ingested by plankton, the foundation of the marine food chain. This can havecascading effects on the entire ecosystem.In conclusion, plastic pollution poses a significantthreat to the ocean and its inhabitants. It endangersmarine life through ingestion and entanglement, anddisrupts delicate ecosystems. Urgent action is needed to reduce plastic waste and prevent further harm to our oceans.中文回答,塑料污染给海洋带来了严重的危害。
Title: Tackling Marine Plastic Pollution: AnIntegrated ApproachMarine plastic pollution has become a global concern, threatening the health of our oceans and the survival of marine life. With the increasing use of plastics in ourdaily lives, the amount of plastic waste entering our oceans is also on the rise. It is imperative that we take action to reduce this menace and protect our preciousmarine environment.One effective way to reduce marine plastic pollution is to promote the use of reusable alternatives to single-use plastics. For instance, encouraging the use of reusable water bottles, shopping bags, and containers cansignificantly reduce the amount of plastic waste entering our oceans. Additionally, promoting the use ofbiodegradable plastics or materials that can be easily recycled can also help in mitigating the problem.Another crucial step is to improve waste management systems, especially in coastal areas. Improper waste disposal is a major contributor to marine plastic pollution. By improving waste collection, sorting, and recyclingfacilities, we can ensure that plastic waste is effectively managed and does not end up in our oceans.Moreover, public awareness and education are key to tackling this issue. People need to understand the impact of their actions on the environment and be motivated to make sustainable choices. Campaigns and initiatives that highlight the dangers of marine plastic pollution and promote sustainable living practices can help raise awareness and encourage people to act.Additionally, innovative technologies and policies can play a crucial role in reducing marine plastic pollution. For instance, developing better waste-to-energy technologies can convert plastic waste into useful energy, reducing the need for landfilling or incineration. Similarly, implementing strict regulations on the production and use of plastics can help reduce the overall demand for these materials.In conclusion, reducing marine plastic pollution requires a comprehensive approach that involves promoting sustainable alternatives, improving waste management systems, raising public awareness, and leveraginginnovative technologies and policies. By working together, we can protect our oceans and ensure a sustainable futurefor ourselves and the planet.**减少海洋塑料污染的综合方法**海洋塑料污染已成为全球关注的问题,威胁着我们的海洋健康和海洋生物的生存。
海洋污染英语定义作文英文回答:Ocean Pollution。
Ocean pollution is the introduction of harmful materials into the ocean environment. These materials can include chemicals, plastics, waste, and noise. Ocean pollution can have a devastating impact on marine life, ecosystems, and human health.Sources of Ocean Pollution。
There are many different sources of ocean pollution, including:Land-based sources: These are pollutants that enter the ocean from land-based activities, such as sewage, industrial waste, and agricultural runoff.Marine-based sources: These are pollutants that enter the ocean from activities that take place in the ocean, such as shipping, fishing, and oil and gas exploration.Types of Ocean Pollution。
There are many different types of ocean pollution, including:Chemical pollution: This is the introduction of harmful chemicals into the ocean environment. Chemical pollutants can include pesticides, herbicides, industrial chemicals, and heavy metals.Plastic pollution: This is the introduction of plastic materials into the ocean environment. Plastic pollution can include plastic bags, bottles, straws, and toys.Waste pollution: This is the introduction of waste materials into the ocean environment. Waste pollution can include sewage, food waste, and medical waste.Noise pollution: This is the introduction of noiseinto the ocean environment. Noise pollution can be caused by ships, construction, and military activities.Impacts of Ocean Pollution。
塑料污染给海洋的带来危害英语作文The Hazards of Plastic Pollution on the Ocean.The ocean, the vast blue expanse that covers over 70% of our planet's surface, is a crucial component of the Earth's ecosystem. It provides a habitat for an immense diversity of marine life, regulates the climate, and supports the livelihoods of billions of people. However, the serene beauty and intricate balance of the ocean are being threatened by a seemingly innocuous but increasingly menacing enemy: plastic pollution.Plastic pollution in the ocean is a global crisis that is rapidly gaining attention due to its pervasive nature and devastating consequences. Plastic debris, ranging from microscopic particles to large floating islands, is being dumped into the ocean every day, originating from both land-based and marine sources. This pollution not only degrades the aesthetic beauty of the ocean but also poses significant threats to marine life, human health, and theoverall functioning of the ocean ecosystem.One of the most immediate impacts of plastic pollution on the ocean is the harm it inflicts on marine life. Many marine animals, including.。
海洋环境中的塑料微粒本文综述了塑料微粒在海洋环境中的生成机制和潜在影响。
降解塑料在海滩上的风化作用导致其表面发生脆化和微裂缝,产生的微粒由风或波浪带入水中。
与存在于海水中的无机粉末不同,塑料微粒常被划分为持久性有机污染物(pop)。
常见的持久性有机污染物的相关分布系数是几个数量级的,塑料介质更是如此。
因此这些高水平的持久性有机污染物被海洋生物群所摄取。
人们对于持久性有机污染物在营养摄取水平方面的利用度和传输效率还不太了解,导致了这些微粒对海洋生态系统造成的潜在危害尚未量化和统一。
在海洋中增加一定水平的污染塑料能更好的了解其在海洋食物网中的影响.关键词:塑料微粒,纳米塑料,持久性有机污染物,塑料,食物网1.介绍第一个报道海洋塑料垃圾的是在1970年代早期,在科学界引起了小小的关注。
在接下来的几十年中,随着越来越多的对生态后果的碎片数据的积累,这一话题得到了持续的研究兴趣。
大多数的研究都集中在海洋哺乳动物,鲸类和其他在垃圾和被废弃的齿轮中的物种之间的纠缠。
摄取塑料的鸟类在世界范围内广为记载和至少有44%的海洋鸟类摄取塑料。
已被证实的有黑脚信天翁雏鸟被喂食塑料颗粒。
随着对北太平洋环流的塑料碎片出人意料的高发现率的报道,这种一开始的兴趣最终成为在海洋生物研究学领域的优先研究课题。
小块的,包括那些肉眼看不见的塑料碎片,被称为微塑性,它在世界上的海洋中是特别令人关注的。
本文试图解决塑料在海洋环境中的命运,分析其在海洋中的机制和潜在的生态影响。
1.1塑料在海洋环境中的使用最近几年全球对塑料的需求一直在增加,目前约为2.45亿吨。
塑料作为一个有多种功能的,重量轻,强大和潜在透明材料,适合各种各样的学术应用。
其低成本、优良的氧化/防潮性能,生物惰性和重量轻使它们优秀的包装材料。
传统的材料,如玻璃,金属和纸被设计优越的塑料包装所取而代之。
近三分之一的塑料树脂生产因被此转化为消费者的包装材料,包括在海滩上常见的一次性物品的塑料碎片。
据不可靠估计,在全球范围内每年大约有70~8000万吨的包装塑料最终流向海洋。
一些塑料被广泛的应用于包装类:聚乙烯(PE)、聚丙烯(PP)、聚苯乙烯(PS),聚对苯二甲酸乙二醇酯(PET),聚氯乙烯(PVC)。
他们的生产数据反映了其大规模的使用,如表1所示,因此这些提高了海洋环境结束的可能性。
广泛的渔业,休闲和海上使用,以及支持移民到沿海地区的人口变化,将增加废塑料未来流入海洋。
约80%的塑料碎片来自陆地和海滩垃圾。
整个全球渔船队现在使用塑料齿轮,有些齿轮在使用过程中必然会丢失甚至丢弃在海上。
聚烯烃(PE和PP),以及尼龙主要应用于渔具。
海洋环境中发现的塑料碎片约有18%是由于捕鱼业。
水产养殖也可以说是塑料碎片在海洋里的一个重要贡献者。
其余大部分来自陆地,包括海滩垃圾。
纯树脂颗粒,碎片的共同组成部分,经常在海洋运输或通过径流处理设施进入海洋。
通过技术排除的漂浮塑料碎片的数量(通常用漂浮生物网来收集水表面的碎片)对于沉积在海洋中的数量来说是非常微不足道的。
碎片作为残核的可见性需要塑料明确的漂浮在海面上(海水比重是1.025)。
然而,从表1中可以看出通常只有少数用于海洋环境的塑料比重低于海水。
(这个比重通常是纯树脂;塑料产品往往是混合填料和其他添加剂,可能会改变他们的比重力)。
密度比较高的品种如尼龙往往淹没在海水中,有的甚至甚至到达海岸泥沙中。
1.2在海洋中的塑料微粒最近有一项重大发现,微小的的塑料碎片,称为微塑料,在世界各地的海洋中出现甚至包括南极洲。
微塑料,一种人造的垃圾,在海洋中至少已经积累了四十年。
从地表水或沙滩上中的垃圾来进行采样,这一部分垃圾包括纯树脂颗粒,复合颗粒和来自较大塑料碎片中的较小颗粒。
不同的研究人员对“microplastcs”和“microlitter”这两个词有不同的定义。
Gregory和Andrady定义“microlitter”为几乎不可见的微粒,它可以通过500 um 但不低于67um的筛子(直径0.06~0.5毫米),大于这个被称为“mesolitter”粒子。
其他人,包括最近的一个相关的研讨会对于微粒的定义是尺寸范围小于5毫米的粒子(用不小于333 um的漂浮生物网来进行抽样)。
海水中塑料粒子的直径通常都是从几微米到500 微米(5毫米)。
为了更清楚的描述,这个尺寸范围被称为“塑料微粒”;更大的粒子如纯树脂颗粒在Gregory和Andrady之后被称为“mesoplas-tics”。
持久性有机污染物(pop)在海水浓度比较低的时候通常被分为中/微塑料。
持久性有机污染物的疏水性,能促进它在中/微垃圾颗粒中的浓度维持在一个水平上,其浓度与它在海水中的浓度相比,高出了好几个数量级。
这些摄入污染塑料的海洋物种为持久性有机污染物可以进入海洋食物网提供了一个可靠的路线。
对于持久性有机污染物中塑料微粒在生物中被溶解的程度和其在食物网中被潜在的放大这一方面并没有被详细研究过。
大塑料微粒是不容易用肉眼见到;甚至树脂颗粒与砂的混合物也是不容易辨别的。
净抽样当然不仅仅是只收集小塑料微粒,就目前来说,还没有可接受的标准程序来计算微粒在水或沙子中数量。
以下只是根据出版报告商以及作者的个人经验所提出的一个建议。
水样通过粗过滤器过滤去除。
在盐水中的沉渣和沙样变为泥浆,让塑料微粒浮到海面。
有一种可以在收集到的海水或泥浆样品中溶解的矿物盐,它加入以后可以增加水的密度,从而使塑料碎片充分的漂浮在水面上。
这样一来就可以对地表水样品与浮动微粒来进行仔细的研究。
浓缩海水样品的蒸发也可以浓缩在海水表面的塑料垃圾。
用亲脂性的染料(如尼罗红)对在地表水样品中的塑料微粒进行染色,使其在能在显微镜下看到。
水样中也会有微生物群存在,例如相同大小的浮游生物,这些将不会被亲脂性的染料染色。
在样品中加入热稀酸对其进行消解可用于去除生物质中的杂质,当然,它不会对微塑料产生任何影响。
塑料微粒悬浮体可以用光学显微镜、电子显微镜、拉曼光谱和红外光谱来进行观察。
下面的图1显示了这一建议抽样方法所分离出来的塑料微粒的图像。
作为学习塑料微粒生殖机制的前提,了解海洋环境中的光致降解和塑料的生物降解是很重要的。
1.3海洋条件下的塑料降解降解是一种化学变化,它大大降低了聚合物的平均分子量。
由于塑料的机械完整性总是取决于其高的平均分子量,任何明显程度的降解都不可避免地削弱了材料。
广泛降解的塑料变得易碎,足以瓦解成粉状碎片得以处理。
即使这些片段,通常肉眼不可见,可以进一步进行降解(一般通过微生物介质进行降解)与聚合物的碳被转化成二氧化碳(并纳入海洋生物量)。
当这一过程完成后,所有的有机碳聚合物都被转换,它被称为完整的矿化。
降解通常根据其降解机制进行分类。
(a)生物降解——生物有机体通常的行动。
(b)光降解——行动的光(通常在户外曝晒的阳光)。
(c)热氧化降解——在中等温度下缓慢的氧化分解。
(d)热降解——高温作用。
(e)水解——与水反应(不是环境降解机制)普通聚合物如LDPE、HDPE、PP和尼龙暴露在海洋环境中主要是太阳光的紫外线辐射,启动光氧化降解。
一旦开始,对于没有进一步暴露在紫外线辐射下的聚合物也可以被降解。
只要系统中含有氧气,催化降解反应便可以进一步进行。
在聚合物中,其分子量下降,聚合物的含氧官能团便会减少。
其他类型的降解过程是数量级的慢光致氧化相比。
相比光诱导氧化,其它类型的降解过程是比较慢的。
在海水中水解通常不是一个重要的机制。
而所有的生物材料,包括塑料,在海洋环境中都是进行生物降解,即使对于深海沉积物来说,它的生物降解速率比光降解速率要慢几个数量级。
在塑料暴露在空气或躺在沙滩表面的时候,太阳紫外线辐射是一种非常有效的机制。
但是,当相同的塑料材料在相同的位置上暴露在阳光下,如果在海水中漂浮,降解速率会明显降低。
在同一地点,比较了几种常见的包装塑料和齿轮分别在空气和海水中的机械完整损失。
如图2(左)所示,聚丙稀的降解速率在急剧下降。
拉伸伸长率(%)作为研究降解机制的一个参数,在海洋环境中,塑料脆化然后被哺乳动物吞噬作为其降解的终点。
其他种类的塑料暴露在海滩或水也经历了类似的降解。
例如,渔具降解的研究。
齿轮的风化作用如聚乙烯网片,暴露在海洋空气中的尼龙丝缠绕都已经被报道。
在海水上漂浮的塑料,其中的元素降解速率较低是由于在相对较低的温度下,环境中的氧浓度较低的结果。
与样品暴露在空气中不同,当它在较低的水环境温度下,会延缓它的反应。
空气和浮动风险之间降解率的差异,使污垢对于它的影响进一步加深。
漂浮的塑料表面会产生大量的污垢,它会迅速的产生藻膜覆盖碎片表面,然后覆盖到一群无脊动物表面。
污损生物的初始速率取决于塑料表面能,5-25nm/m的材料是最小界限范围。
在Biscayne表面的演替依次为细菌-硅藻-水螅-藤壶-水云目藻类苔藓虫。
但是,结构序列和动力学是强烈依赖与水的条件和曝光的季节的。
塑料碎片中都镶有金属物,随着污染过程其密度会逐渐增加,一旦密度大于海水,便会沉到水面以下。
在一定深度的水中,漂浮塑料碎片的密度变化是由于其缓慢循环摆动的生态系统,这种机理在后来得到了证实。
不规则碎片会随着其密度的增加,最终会到达底栖区。
在海底会经常发现塑料。
即使是一个广泛的风化,脆塑料材料(即分崩离析处理),其分子量仍有千克/摩尔。
图3说明了拉伸生长率(%)与聚乙烯的平均分子量的对数的关系。
即使在图的最左边(对应于广泛的降解或催化材料),Mn的含量也为1000~10000克/摩尔。
这些低分子量的塑料并没有进行生物降解。
同时也对锰含量为500可克/摩尔进行了观察。
光氧化所导致的粒径减小对塑料碎片的后续降解并没有一定的帮助。
高分子塑料中的许多物质在微生物的降解速率是不一样的。
因此,它能在微生物中聚合是非常罕见的。
在海洋环境中尤其如此,除了生物聚合物如纤维素和甲壳素。
然而,最近的研究已经确定了几个品种的微生物能降解聚乙烯和聚氯乙烯。
在实验室中培养浓缩液体,放线菌红球菌使聚烯烃的干重在30天的潜伏期内减少了约8%。
漆酶分泌的物种减少平均分子证明了GPC表明降解聚合物的重量通过切断主链。
然而,在足够高的浓度下,这个过程不会在发生土壤微生物或海洋环境中,但竞争营养来源是永远存在的。
在海洋环境中,几乎没有任何的关于塑料矿化动力学的数据。
然而,生物聚合物如甲壳素和一些合成聚合物在海中能快速的生物降解。
淀粉填充的聚烯烃有时被错误地称为“降解”,但淀粉只有在海洋环境中的矿化中才存在。
理想情况下,聚合物材料的处理环境应该完全生物降解释放碳碳循环。
矿化是塑料完整的转换成二氧化碳、水和生物质能。
尼龙等聚合物包含C、H、O、N的化学反应,转换如下:在实验室用呼吸法模拟海洋暴露下的碳转化率。
很好的聚合物在生物介质中培养,如沿海海洋沉积物和二氧化碳气体进化生物降解被量化。