生物多样性及其价值: 生物多样性是生物及其与环境形成的生态复合体以及与此相关的各种生态过程的总和，还有包括数以百万计的动物、 植物、 微生物和它们所拥有的基因以及它们与其生存环境形成的复杂的生态系统，就是生命系统的基本特征。生命系统是一个等级系统，不仅包括多个层次或水平：基因、细胞、组织、器官、种群、物种、群落、生态系统、景观，并且每一个层次都具有丰富的变化，即都存在着多样性。但在理论与实践上重要且研究较多的主要有基因多样性（或遗传 多样性） 、物种多样性、生态系统多样性和景观多样性。现在，人们往往把生物多样性视为生命实体本身，而不仅仅看作生命系统的重要特征之一。生物多样性是人类赖以生存的物质基础，其价值可以从下列两个方面得以了解。

• 直接价值。

• 间接价值。

随着时间的推移， 生物多样性的最大价值可能在于为人类提供适应 当地和全球变化的机会。 生物多样性的未知潜力为人类的生存与发展展示了不可估量的美好前景。但是近年来，物种灭绝的加剧，遗传多样性的减少，以及生态系统特别是热带森林的大规模破坏，引起了国际社会对生物多样性问题的极大关注。 生物多样性丧失的直接原因主要有 生境丧失、外来种的侵入、生物资源的过度开发、环境的污染、全球气候的变化和工业化的农业及林业等。但这些还不是问题的根本所在，根源在于人口的剧增和自然资源消耗的高速度、不断狭窄的农业、林业和渔业的贸易谱、经济系统和政策未能评估环境及其资源的价值、 生物资源利用和保护产生的惠益分配的不均衡、知识及其应用的不充分以及法律和制度的不合理。总而言之，人类活动是造成生物多样性以空前速度丧失的根本原因。中国是生物多样性特别丰富的国家之一。据统计，中国的生物多样性居世界第八位，北半球第一位。同时，中国又是生物多样性受到最严重威胁的国家之一。中国的原始森林长期受到乱砍滥伐、毁林开荒等人为活动的影响，其面积以每年0．5×104km2 的速度减少；草原由于超载过牧、毁草开荒的影响，退化面积达 87×104km2。生态系统的大面积破坏和退化，不仅表现在总面积的减少，更为严重的是其结构和功能的降低或丧失使生存其中的许多物种已变成濒危种或受威胁种。高等植物中有 4000—5000 种受到威胁，占总种数的 15％ —20％。在“濒危野生动植物种国际贸易公约”列出的 640个世界性濒危物种中，中国就占156 种，约为其总数的 1／4，形势是十分严峻的。 生物多样性保护关系到中国的生存与发展。

Biodiversity and its value: biodiversity is the sum of organisms and their ecological complexes formed with the environment and various ecological processes related to it. There are also millions of animals, plants, microorganisms and their genes as well as the complex ecosystem formed by them and their living environment, which is the basic characteristics of life system. Life system is a hierarchical system, not only including multiple levels or levels: gene, cell, organization, organ, population, species, community, ecosystem, landscape, and each level has rich changes, that is, there are diversity. However, in theory and practice, genetic diversity (or genetic diversity), species diversity, ecosystem diversity and landscape diversity are the main research areas. Nowadays, people tend to regard biodiversity as the life entity itself, not only as one of the important characteristics of the life system. Biodiversity is the material basis for human survival, and its value can be understood from the following two aspects.

 

First, direct value.

 

Second, indirect value.

 

Over time, the greatest value of biodiversity may lie in providing opportunities for humans to adapt to local and global changes. The unknown potential of biodiversity shows an immeasurable bright future for human survival and development. However, in recent years, the aggravation of species extinction, the reduction of genetic diversity, and the large-scale destruction of ecosystems, especially tropical forests, have aroused great concern of the international community on biodiversity. The direct causes of biodiversity loss include habitat loss, invasion of alien species, overexploitation of biological resources, environmental pollution, global climate change and industrialized agriculture and forestry. But these are not the root of the problem. The root causes lie in the sharp increase of population and the high rate of consumption of natural resources, the increasingly narrow trade spectrum of agriculture, forestry and fishery, the failure of economic systems and policies to assess the value of the environment and its resources The unbalanced distribution of benefits from the utilization and protection of biological resources, the inadequacy of knowledge and its application, and the irrationality of laws and systems. All in all, human activities are the root cause of the unprecedented loss of biodiversity. China is one of the countries rich in biodiversity. According to statistics, China's biodiversity ranks eighth in the world and the first in the northern hemisphere. At the same time, China is one of the countries with the most serious threat to biodiversity. For a long time, China's primitive forests have been affected by deforestation, deforestation and other activities, and their area has decreased at a rate of 0.5 × 104km2 per year. Due to the impact of overloading and overgrazing, grassland degradation area reaches 87 × 104km2. The large-scale destruction and degradation of ecosystem is not only manifested in the reduction of the total area, but also in the reduction or loss of its structure and function. Many species have become endangered or threatened species. 4000-5000 species of higher plants are threatened, accounting for 15% - 20% of the total species. Among the 640 endangered species listed in the Convention on international trade in endangered species of Wild Fauna and flora, China accounts for 156 species, accounting for about 1 / 4 of the total. Biodiversity protection is related to the survival and development of China.