生物多样性不是奢侈品,而是必需品

Encyclopédie environnement - biodiversité - biodiversity

  生物多样性(biodiversity)是英文中“生物的”(biological)和“多样性”(diversity)的合成词,在1992年举办的“地球峰会”上首次出现在公众领域。这个词有两种含义:在生命科学领域,关注其生物组成;在人文和社会科学领域,关注社会对其管理以及内在价值的思考。生态系统功能和服务的概念确立后,在物种生物学与社会福祉之间建立动态联系成为可能。结合“全球变化”一词,导致生物多样性丧失的几个因素对社会福祉带来严重风险,新的生态治理形式应减轻此类风险。

1. 什么是生物多样性?

环境百科全书-生物多样性不是奢侈品,而是必需品-地球上有多少物种
图1. 地球上有多少物种?目前已被描述的物种大约有200万种,但实际数量可能在1000万到3000万种之间。如图所示,不同类群之间已描述的物种数量差异很大。尽管人们已经相当了解脊椎动物,但每年仍有新的一些哺乳动物和鸟类得到描述,更不用说两栖动物、爬行动物和鱼类。但人类对真菌、线虫和昆虫等类群的多样性仍然知之甚少,这些类群中的很大一部分物种甚至在被发现和被描述之前就已经灭绝了。这种统计没有将原核生物(没有细胞核的生物)考虑在内,如细菌和古生菌,它们有数十亿个不同的实体或菌株,其功能对于生命的存在具有重要作用。
Described species 已被描述物种
Undescribed species 未被描述物种
Nematodes 线虫
Crustacean 甲壳动物
Protozoan 原生动物
Algae 藻类
Vertebrates 脊椎动物
Molluscs 软体动物
Fungi 真菌类
Arachnids 蛛形纲动物
Plants 植物
Insects 昆虫

  “生物多样性”一词于1986年在美国举行的生物多样性论坛上首次提出,当时科学界意识到全球生物多样性正在减少,这一现象令人担忧。但是,直到1992年6月联合国召开环境与发展会议,即里约热内卢地球峰会,“生物多样性”一词才被公众和媒体熟知。它最初被定义为生态系统、物种(图1)和基因在空间和时间上的多样性,以及它们在这些结构层级内部和之间的相互作用,后来被广泛应用于各个领域,因此很难再为其找到一个能被广泛接受的正式且简单的定义。

  实际上,“生物多样性”一词有两个互补的含义。

  • 第一个是将生物多样性视为一个实体层级结构(基因、个体、种群、物种、生态系统),作为永久进化(时间维度)的交互系统,受动态(空间维度)驱动并发挥功能。该定义反映了三个基本概念,即生物多样性要素之间的相互作用、它们在空间中的动态(即生态)和它们的时间轨迹(即进化)(见《什么是生物多样性?》)。
  • 第二个是将生物多样性视为一种社会、经济、法律、政治和哲学结构,其面临的挑战与和人类社会的互动有关:人类从生物多样性获取资源、利用资源、受益于其资源、共享并管理生物多样性、维系生物多样性的可持续性。

  因此,从实际层面来看,生物多样性是一个科学界的优先事项,需要通过了解其起源、进化、组织和在生态系统中的功能,竭尽所能阻止其受到侵蚀。这就是生命科学界正在做的事情。但这也是一个经济和社会问题,因为它所代表的生物和遗传资源必须在个人和国家层面得到重视和公平共享。最后,这是一个伦理问题,因为它引发了物种生命权的问题,环境伦理等几个活跃的哲学思潮认为,这不受法令约束也不可剥夺。

  环境伦理学质疑以西方人类中心主义制定物种和自然系统的开发和管理标准是否合理。根据非人类中心主义的观点,每个生物都是“目的论的生命中心”,因此必须将其本身视为目的,这是使其成为道德考量对象并承认其内在价值的必要和充分条件。正是在这种背景下,几个立场之间出现了哲学上的分歧,特别是在“生物中心主义和“生态中心主义之间,前者在个体层面上捍卫生命、每一种生命体,而后者倡导生物群落的完整性,即一个包括所有其组成的有机体(包括人类)的复杂生态系统。生态中心主义是目前思考人类社会与自然系统之间关系的首选方案

  因此,生物多样性显然也属于人文和社会科学的一部分。

2. 功能、服务和价值

  经过了长期的割裂,目前生物多样性研究倾向于整合生态系统功能和生态系统服务,尤其是在联合国倡议下为《生物多样性公约》(CBD)进行千年生态系统评估之后。该国际条约于1992年在里约热内卢举行的地球峰会通过,旨在(i)保护生物多样性,(ii)确保其组成部分的可持续利用,以及(iii)公平和公正地共享使用遗传资源所产生的惠益。《生物多样性公约》是可持续发展的重要文件,其中生物多样性被列为一个关键性问题。自2012年以来,由联合国环境规划署(UNEP)发起的政府间生物多样性和生态系统服务平台(IPBES)召集了一个专家小组,类似于联合国政府间气候变化专门委员会(IPCC)。

环境百科全书-生物多样性不是奢侈品,而是必需品-生物多样性、生态功能、服务与社会的关系
图2. 生物多样性、生态系统功能、生态系统服务与社会的关系。过大压力会导致几种类型的损害(全球变化)。
global changes 全球变化
biodiversity 生物多样性
services 生态系统服务
functions 生态系统功能

  生物多样性与人类社会之间关系的逻辑基于生态系统功能和服务的概念(图2):生态系统功能是支持生态系统的基本过程,例如授粉、初级生产力、营养级之间的关系(食物链)、有机物质循环、种群调节等。生态系统服务是人类从这些功能中获得的好处,即衣食住行、健康等所需的一切,还包括许多其他服务,如气候调节、水净化、碳封存、病原体控制等等。当生态系统承受的压力过大时,会随物种的丧失、相互作用中断而退化,导致功能的改变和服务的匮乏。如今,生物多样性的丧失是全球各地普遍面临的一个重大问题。物种以人类历史上罕见的速度消失,令人痛惜,但最令人担忧、最可怕的影响是空间碎片化、基因贫瘠化(genetic impoverishment)和在景观层面本地种群的消失,这是一种对生命结构的磨损,影响了生态系统的功能。

环境百科全书-生物多样性不是奢侈品,而是必需品-生物多样性被认可的不同类型的价值
图3. 生物多样性被认可的不同类型的价值。来源:Chevassus-au-Louis等人(2009)。
Economic Value of biodiversity 生物多样性的经济价值
Use 使用价值
Value of direct use 直接使用价值
Value of indirect use 间接使用价值
Value of option 可选价值
directly consumable 直接消耗
functional advantages 功能优势
potential future use 潜在的未来用途
food 食物
wood 木材
biomass 生物量
externalities 外部效应
protection functions 保护功能
ecological functions 生态功能
hydrologic functions 水文功能
climatic functions 气候功能
conservation 生态保护
durability 持久性
diversity production 多样性生产
habitats conservation 生境保护
landscapes 景观
Non-use 非使用价值
inheritance value 继承价值
existence value 存在价值
conservation for the future generations 保护后代
valeurs placees sur le non-usage 非使用价值
habitats & ecosystems 生境和生态系统
irreversible changes 不可逆变化
landscapes 景观
habitats & ecosystems 生境和生态系统
endangered species 濒危物种
tangibility 有形性

  根据生物多样性的服务和资源的概念,同时也为了保护生物多样性,经济界掌握了这一概念并赋予了不同层次的价值,这具有一定难度,因为“价值”一词的不同含义可能导致相互矛盾的做法(图3)。当人类通过金融交易赋予生物多样性实体货币价值时,这个价值与人类认可生物多样性作为独特生命实体的价值没有关系。

3. 全球变化及生物多样性

  “全球变化”一词是指对生态系统产生过度压力导致的所有退化因素,这种压力已经成为“人类世”一词的由来,该词语以人类足迹为标志的一个新的地质时代,其影响遍及全球。全球变化分为六个主要部分:(i)生境改变和破碎化,(ii)污染(各种形式),(iii)化学投入(农药、化肥),(iv)入侵物种(包括转基因生物),(v)资源过度开发,以及(vi)气候变化。这些压力导致的生物多样性丧失难以估计,但可以通过几个指标评估。我们正在谈论的这种生物多样性丧失是第六次大灭绝危机,其他五次从泥盆纪(距今3.7亿年前)一直蔓延到白垩纪末期(距今6500万年)。后者导致了恐龙的灭绝,但促进了鸟类和哺乳动物的发展。

  由于许多现已众所周知的原因,人类社会的福祉取决于他们能否融入生态系统且生态系仍能发挥功能,这需要制定新的、更有利于环境的管理标准。保护科学有助于确定这些标准,并为制定有效的空间和物种管理政策提供必要的专业知识。在制度层面,欧盟正在采取或已经采取许多措施,例如1992年栖地指令Habitats Directive),自然保护区网络(Natura 2000)和2009年鸟类指令(Birds Directive)。法国也通过多项举措致力于保护生物多样性,特别是通过1976年的自然保护法以及在格勒诺布尔环境会议后的立法。2007年,法国启动了一个蓝绿基础设施项目。最近,随着《重新征服生物多样性、自然和景观法》(,Law for the Reconquest of Biodiversity, Nature and Landscapes(2016年)的颁布,法国生物多样性局也成立了,这是一个关于生物多样性的专业知识和管理机构,将有助于国家生物多样性战略的实施。另一个有效的研究和专业知识机构是法国生物多样性基金会。希望所有这些措施都将取得成果,但目前确实进展有限,除个别地方外,趋势指标仍未显示世界范围内的生物多样性状况得到改善。

 


参考资料及说明

封面照片:《粉红火烈鸟》(1907年,私人收藏)


环境百科全书由环境和能源百科全书协会出版 (www.a3e.fr),该协会与格勒诺布尔阿尔卑斯大学和格勒诺布尔INP有合同关系,并由法国科学院赞助。

引用这篇文章: BLONDEL Jacques (2024年3月8日), 生物多样性不是奢侈品,而是必需品, 环境百科全书,咨询于 2024年10月11日 [在线ISSN 2555-0950]网址: https://www.encyclopedie-environnement.org/zh/vivant-zh/biodiversity-is-not-a-luxury-but-a-necessity/.

环境百科全书中的文章是根据知识共享BY-NC-SA许可条款提供的,该许可授权复制的条件是:引用来源,不作商业使用,共享相同的初始条件,并且在每次重复使用或分发时复制知识共享BY-NC-SA许可声明。

Biodiversity is not a luxury but a necessity

Encyclopédie environnement - biodiversité - biodiversity

Biodiversity, a contraction of the term “biological diversity”, appeared in the public sphere at the Earth Summit (1992). Two meanings are recognized in the word. The first in Life sciences concerns its biological component, while the second in Human and Social sciences is concerned with how society manages it, including consideration for its intrinsic value. The concepts of ecosystem functions and services make it possible to establish operational links between the biology of species and the welfare of society. Several factors of biodiversity loss, combined under the term “global change”, are serious risks to the well-being of societies that new forms of ecological governance should mitigate.

1. What is biodiversity?

Figure 1. How many species are there on Earth? Approximately 2 million species are currently described, but the actual number is probably in the order of 10 to 30 million. As illustrated in this figure, the number of species described varies greatly between groups. While vertebrates are fairly well known, although several species of mammals and birds are described each year, not to mention amphibians, reptiles and fish, the diversity of groups such as fungi, nematodes and insects remains very poorly known to the extent that a large part of the species in these groups will be extinct before having even been discovered and described. This balance does not take into account prokaryotes (organisms without a cell nucleus) such as bacteria and archaea, which number in billions of distinct entities or strains and whose functional role is fundamental to life

The neologism Biodiversity was coined at a forum on biological diversity held in the United States in 1986 in the context of a scientific community’s awareness of the worrying erosion of biological diversity around the world. But it was the United Nations Conference on Environment and Development, better known as the Rio de Janeiro Earth Summit in June 1992, that popularized the term among the general public and the media. Initially defined as the diversity of ecosystems, species (Figure 1) and genes in space and time, as well as their interactions within and between these organizational levels, it is used in such a wide range of situations that it is no longer possible to give it a formal and simple definition that is accepted by all.

Actually, the word “biodiversity” has two complementary meanings.

  • The first is to consider biodiversity as a hierarchy of entities (genes, individuals, populations, populations, species, ecosystems) organized as interactive systems in perpetual evolution (dimension of time), driven by dynamics (dimension of space) and performing functions. This definition reflects three essential concepts, namely, the interactions between elements of biodiversity, their dynamics in space (i.e. ecology) and their temporal trajectory (i.e. evolution) (see What is biodiversity?).
  • The second is to consider biodiversity as a social, economic, legal, political and philosophical construct whose challenges are related to its interactions with human societies: access to resources, uses, benefits, sharing, management, sustainability.

From an operational point of view, biodiversity is therefore a scientific priority aiming at understanding its genesis, evolution, organization and functions within ecosystems, as well as stopping its erosion whenever and wherever possible. This is what the scientific community in the Life Sciences is doing. But it is also an economic and social issue because of the biological and genetic resources it represents, which must be valued and shared equitably at the level of individuals and States. Finally, it is an ethical issue because it raises the question of the right to life of species, which can be considered imprescriptible, as advocated by several active philosophical currents such as environmental ethics.

Environmental ethics raises the question of the legitimacy of Western anthropocentrism in the construction of standards for the exploitation and management of species and natural systems. According to a non-anthropocentric vision, every living being is a “teleological centre of life” and must, as such, be considered as an end in itself, a necessary and sufficient condition for it to be recognized as having an intrinsic value that makes it a subject of moral consideration. It is in this context that a philosophical cleavage emerged between several postures, in particular between “biocentrism” which defends the living, every living item, at the individual level and “ecocentrism” which advocates the integrity of the biotic community, a complex ecological system that includes all the organisms that compose it, including humans. Ecocentrism is currently a preferred option for thinking about the relationships between human societies and natural systems.

Biodiversity is therefore also explicitly part of the Humanities and Social Sciences.

2. Functions, services and values

For a long time compartmentalized, biodiversity research is currently tending to integrate functions and services, particularly following the work of the Millennium Ecosystem Assessment prepared at the initiative of the UN for the Convention on Biological Diversity (CBD). This international treaty, adopted at the Earth Summit in Rio de Janeiro in 1992, aims to (i) conserve biodiversity, (ii) ensure the sustainable use of its components and (iii) share fairly and equitably the benefits arising from the use of genetic resources. The CBD is a key document for sustainable development in which biodiversity is considered a key issue. Since 2012, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), launched by the United Nations Environment Programme (UNEP), is bringing together a panel of experts launched as a group something like the Intergovernmental Panel on Climate Change (IPCC).

Figure 2. Relationships between biodiversity, ecological functions, services and society. Excessive pressure can lead to several types of damage (global change)

The logic of the relationships between biodiversity and human societies is based on the concepts of ecosystem functions and services (Figure 2): functions are the basic processes that support ecosystems such as pollination, primary productivity, relationships between trophic levels (food chains), organic matter recycling, population regulation, etc. Services are the benefits that humans derive from these functions, namely everything they need to feed, clothe or health themselves, but also a multitude of services such as climate regulation, water purification, carbon sequestration, pathogen control, etc. When pressures on ecosystems are excessive, they degrade through loss of species, disruptions of interactions, and thus alteration of functions and impoverishment of services. The erosion of biodiversity is now a major concern everywhere on Earth. While the disappearance of species at a rate never seen before in human history is rightly deplored, the most worrying and pernicious effect of this erosion is the fragmentation in space, genetic impoverishment and the disappearance of local populations at the landscape level, a kind of fraying of the fabric of life that affects the functioning of ecosystems.

Figure 3. The different types of values recognized for biodiversity. According to Chevassus-au-Louis et al (2009).

In line with the notion of services and capital attributed to biodiversity, but also admittedly for conserving it, the economic world has captured the concept to assign various levels of values, which is not without difficulties because the different meanings of the word value can lead to contradictory practices (Figure 3). When we monetize the value of a biodiversity entity through a financial transaction, the value we attribute to it has nothing to do with the value we recognize it as a unique living entity.

3. Global change and biodiversity

The term “global change” refers to all the factors of degradation resulting from excessive pressure on ecosystems, this pressure having become such as the term “AnthropoceneNeologism associating the Greek words “man” and “recent”, coined by the meteorologist and atmospheric chemist Paul Crutzen, Nobel Prize for Chemistry in 1995, to designate a new geological era. The anthropocene would have begun with the industrial revolution and would thus succeed the Holocene, the geological era after the last glaciation and which covers the last ten millennia.” as been coined as a new geological era marked forever by a human footprint whose effects are felt throughout the planet. The global change is divided into six main components: (i) habitat alteration and fragmentation, (ii) pollution (in all its forms), (iii) chemical inputs (pesticides, fertilizers), (iv) invasive species (including GMOs), (v) overexploitation of resources, and (vi) climate change. These pressures lead to biodiversity loss that is difficult to estimate but can be assessed by several metricsUnits or measurement indicators used to judge the effectiveness of an activity.. This erosion is such that we are talking about a sixth major extinction crisis, the other five having spread from the Devonian (370 million years before the present) to the latest at the end of the Cretaceous (65 million years). The latter led, among other things, to the extinction of dinosaurs but encouraged the development of birds and mammals.

For many reasons that are now well known, the well-being of human societies depends on their integration into ecological systems that are as functional as possible, which requires new and more environmentally friendly management standards. Conservation science helps to define these standards and provides the expertise necessary to develop effective policies for managing space and species. At the institutional level, many measures are being taken or are in the process of being taken at the European Union level. This is the case, for example, of the 1992 Habitats Directive and its network of protected sites Natura 2000 and the 2009 Birds Directive. France has committed itself to biodiversity through numerous initiatives, notably through the 1976 law on the protection of nature and then through the laws of the Grenelle de l’Environnement, in 2009 and 2010. A project for a green and blue grid has been launched in 2007. More recently, Law for the Reconquest of Biodiversity, Nature and Landscapes (2016) has been accompanied by the creation of the French Biodiversity Agency, a place of expertise and management of biodiversity that will contribute to the implementation of the National Biodiversity Strategy. Another effective research and expertise tool is the French Foundation for Biodiversity. It is to be hoped that all these measures will bear fruit, which is not yet the case, as the trend indicators do not yet show, but with local exceptions, any improvement in the state of biodiversity worldwide.

 


References and notes

Cover image. The pink flamingos, Douanier Rousseau (1907, private collection)


环境百科全书由环境和能源百科全书协会出版 (www.a3e.fr),该协会与格勒诺布尔阿尔卑斯大学和格勒诺布尔INP有合同关系,并由法国科学院赞助。

引用这篇文章: BLONDEL Jacques (2020年3月2日), Biodiversity is not a luxury but a necessity, 环境百科全书,咨询于 2024年10月11日 [在线ISSN 2555-0950]网址: https://www.encyclopedie-environnement.org/en/life/biodiversity-is-not-a-luxury-but-a-necessity/.

环境百科全书中的文章是根据知识共享BY-NC-SA许可条款提供的,该许可授权复制的条件是:引用来源,不作商业使用,共享相同的初始条件,并且在每次重复使用或分发时复制知识共享BY-NC-SA许可声明。