英语翻译9.2.2 Carbon Fixation and Energy FlowThe ability to phot

英语翻译
9.2.2 Carbon Fixation and Energy Flow
The ability to photosynthesize allows sunlight energy to be trapped and stored.In this process carbon dioxide is fixed into organic matter (Fig.9.1).Photosynthetic organisms,also called primary producers,include plants and microorganisms such as algae,cyanobacteria,some bacteria,and some protozoa.As shown in Fig.9.2,the efficiency of sunlight trapping is very low; less than 0.1% of the sunlight energy that hits the earth is actually utilized.As the fixed sunlight energy moves up each level of the food chain,up to 90% or more of the trapped energy is lost through respiration.Despite this seemingly inefficient trapping,photoautotrophic primary producers support most of the considerable ecosystems found on the earth.Productivity varies widely among different ecosystems depending on the climate,the type of primary producer,and whether the system is a managed one (Table 9.5).For example,one of the most productive natural areas is the coral reefs.Managed agricultural systems such as corn and sugarcane systems are also very productive,but it should be remembered that a significant amount of energy is put into these systems in terms of fertilizer addition and care.The open ocean has much lower productivity,but covers a majority of the earth's surface and so is a major contributor to primary production.In fact,aquatic and terrestrial environments contribute almost equally to global primary production.Plants predominate in terrestrial environments,but with the exception of immediate coastal zones,microorganisms are responsible for most primary production in aquatic environments.It follows that microorganisms are responsible for approximately one half of all primary production on the earth.

9.2.2固碳和能量流
在光合作用的能力让阳光能源将被困和储存.在这一过程中的二氧化碳固定成有机物质（图9.1 ） .光合生物,也称为初级产品生产者,包括植物和微生物,如藻类,蓝藻,一些细菌,以及一些原生动物.正如图所示.9.2 ,效率的阳光捕获非常低;不到0.1 ％的太阳光能量,地球安打实际上是利用.作为固定的阳光能源上升每个级别的食物链,高达90 ％或以上的被困能源是失去呼吸.尽管这个看似低效的陷阱,光合初级产品生产者支持大多数生态系统发现大量地球上.生产力差别很大不同生态系统之间的不同气候类型的主要生产国,以及是否系统是一个管理一（表9.5 ） .举例来说,一个最富有成效的自然区是珊瑚礁.管理农业系统,如玉米,甘蔗,系统也非常有成效的,但应该记住,大量的能源投入这些系统而言,除了化肥和照顾.开放的海洋生产力低得多,但涵盖了大部分的地球表面,因此作出了重要贡献初级生产.事实上,水和陆地环境作出贡献几乎同样对全球初级生产.植物主要在陆地环境,但除立即沿海地区,微生物负责生产最初级的水环境.因此,微生物负责大约有一半的初级生产在地球上.