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1、B3 B3 生生 态态 位位 要 点 有机体的生态位（niche）是它在它的环境中所处的位 置，包括它发现的各种条件、所利用的资源和在那里 的时间。 有机体的栖息地（habitat，或译生境）是它所处的物理 环境，例如，温带阔叶林。每一个栖息地提供许多生 态位。 定义有机体生态位的每一个条件和资源，对于有机体 能出现的空间提供一个维度。一起考虑所有维度，全 面确定的有机体的生态位，是多维生态位空间，或“n- 维超体积”。 生 态 位 栖 息 地 多维生态位空间 The ecological niche of an organism is the position it fills in its
2、 environment, comprising the conditions under which it is found, the resources it utilizes and the time it occurs there. Key Notes The habitat of an organism is the physical environment it is found in, for example, a temperate broad-leaved woodland. Each habitat provides. Each condition or resource
3、which defines the niche of an organism contributes one dimension to the space in which the organisms niche, and is the multidimensional niche space, orn-dimensional hypervolume. B3 B3 T T HE NICHEHE NICHE Niche Habitat Multidimensional niche space 基础生态位 在没竞争和捕食条件下，有机体的生态位空间叫做基 础生态位（fundamental niche
4、）。 相关主题竞争的性质（见I1） 资源分配（见I3） 种内竞争（见I2） 实际生态位 当有竞争和捕食出现时，有机体所占有的生态位空间 是实际生态位（realized niche），实际生态位始终是基 础生态位的一个子集。 The niche space an organism can fill in the absence of competition or predation is known as the fundamental niche. The niche space occupied by an organism when competition and predation oc
5、cur is the realized niche, which is always a subset of the fundamental niche. The nature of competition (11) Resource partitioning(13) Intraspecific competition (12) Fundamental niche Realized niche Related topics G1 G1 资源与循环资源与循环 要 点 营养物资源 群落以形形色色的方式获得和损失营养物。机械风化 、化学腐蚀，特别是碳酸化作用，都是重要的过程。 矿物质在水中的简单溶解
6、也使营养物从岩石和土壤中 获得成为可能。在水流中水可能携带着营养物，给下 流地区提供一个重要的资源。大气也提供营养物，特 别是二氧化碳和氮。大气中其他营养物可能以湿降落 （雨，雪和雾）和干降落（干燥期间的颗粒沉淀物） 的方式回到群落。 G1 G1 S SOURCES AND CYCLESOURCES AND CYCLES Nutrients are gained and lost by communities in a variety of ways. Mechanical weathering, chemical weathering, particularly carbonation, a
7、re important processes. Simple dissolution of minerals in water also makes nutrients available from rock and soil. Water may carry nutrients in watercourses providing an important source in downstream areas. Atmospheric gases provide nutrient sources too, particularly carbon dioxide and nitrogen. Ot
8、her nutrients from the atmosphere become available to communities as wetfall (rain, snow and fog) and dryfall (settling of particles during dry periods). Key Notes Nutrient sources 陆地群落营 养物预算 有机体吸收的特定营养物微粒可连续地循环，直到营 养物最终损失，这是通过许多过程中的任一个过程把 营养物从系统中除去。营养物释放可直接到达空气或 通过细菌作用（如甲烷）。对于许多元素来说，最重 要的是丢失途径是在水流中
9、。营养物损失的其他途径 包括火灾、庄稼的收获和森林砍伐。 A particular nutrient atom taken up by an organism may cycle continuously until eventually the nutrient will be lost through any one of a number of processes that remove nutrients from the system. Release may be direct to the atmosphere or via bacterial action (as in the
10、 case of methane). For many elements, the most substantial pathway of loss is in streamflow. Other pathways of nutrient loss include fire, the harvesting of crops and deforestation. Nutrient budgets in terrestrial communities 水生群落营养 物预算 水生系统从水流中得到它们所需的大量营养物。在具 有流出口的溪流、河流和湖泊中，水流出是个重要因 素。通常，无机营养物置换阶段与
11、营养物固定在生物 量中的时期是交替进行的。浮游生物在湖泊中的营养 物循环中起关键作用。海洋含有温暖的表层水，生活 着大多数的植物，还有冷的深层水（占总水容量的90% ）。表层水的营养物来源于两种方面：（i）深层水的 上涌流（组成物预算的95%以上），（ii）河流的输入 。 Aquatic systems obtain the bulk of their supply of nutrients from streamflow. In streams, rivers and lakes with a stream outflow, export in outgoing stream water i
12、s a major factor. Commonly, phases of fast inorganic nutrient displacement alternate with periods when the nutrient is locked in biomass. In lakes, plankton play a key role in nutrient cycling. Oceans contain warm suface waters, where most plant life is found and cold deep waters (which make up 90%
13、of the total water volume). Nutrients in the suraface waters come from two sources: (i) upwelling from deep water (which comprise over 95% of the nutrient budget),and (ii) river input. Nutrient budgets in aquatic communities 地球化学 地球上的化学元素库存在于各种圈层（compartments） 中：在岩石（岩圈）和土壤水、溪流、湖泊或海洋（ 可组合构成水圈）中。在上述情况
14、下，化学元素以无 机形式存在。同时，生命有机体和已死亡及腐烂的有 机物质是在含有有机元素的圈层里。研究在这些区域 内发生的化学过程和圈层间元素的流动（通过生物过 程产生了功能性的改变和影响），称为生物地球化学 。 The pools of chemical elements on earth exist in various compartments: in rocks (the lithosphere), and soil water, streams, lakes or oceans (whish, combined, constitute the hydrosphere). In all
15、 these cases, the chemical elements exist in the inorganic form. In contrast, living organisms and dead and decaying organic matter are compartments which contain elements in the organic form. Studies of the chemical processes occurring within these compartments and the flux of elements between them
16、 (which are fundamentally altered and affected by biotic processes) is termed biogeochemistry. Geochemistry 全球生物地化 循环 陆地植物利用空气中CO2作为光合作用的碳源，而水生 植物使用溶解的碳酸化合物（水圈的碳）。呼吸作用 把固定在光合产物中的碳，再释放到气圈和水圈的碳 圈层中。在全球氮循环中，气相是占优势的，其中， 氮的固定和微生物的脱氮作用特别重要。磷主要储存 在土壤水、河流、湖泊、岩石和海洋沉淀物中，而硫 储存在大气和岩石的组分中。 相关主题植物与消费者（G2） 土壤形成、特性和分类（G3节 ）初级和次级生产力（P2） Terrestrial plants utilize atmospheric CO2 as their carbon source for photosynthesis, whereas aquatic plants use dissolved carbonates (hydrospher
