生态

Due to its active and effective character,dissolved organic nitrogen plays an important role in the terrestrial nitrogen cycle.

本文就陆地生态系统DON的来源、组成、性质；森林生态系统DON的流动、季节动态以及DON在氮循环中的地位等方面作了概括和探讨。

This paper first report the distribution and role of four nitrogen cycle bacteria in the artificial ecosystem of Taihu Lake.

对太湖五里湖的以水生高等植物为主的湖泊人工生态系统，用最大可能数法，测定了该系统内各种生态类型水生高等植物群落内的4类氮循环细菌的分布。

Nitrogen cycle is very important for forest ecosystem,and soil N mineralization rate is often used as the index of soil N availability and its losses.

氮在森林生态系统的养分循环中很重要，常把土壤氮矿化速率作为生态系统中氮有效性和氮损失的指标。

A clone from each genotype was randomly selected as representative for sequencing. The obtained 16S rDNA gene sequences had a similarity of 87%-100% with those in the GenBank (www. ncbi. nlm. nih. gov), and more than half of them had a similarity lower than 97%, being of new species. Based on phylogenetic analysis, the bacteria in the two soils were classified into 10 groups, with 5 groups in common. The dominant bacterial groups in the two soils differed obviously. In primeval forest soil, the dominant group was Proteobacteria, which had 39 genotypes, occupying 58.0% of all the clones; while in the soil of degraded ecosystem the dominant groups were Acidobacteria and Proteobacteria, which had 19 and 15 genotypes occupying 32.5% and 30.5% of all the clones, respectively. In the soil of degraded ecosystem, Proteobacteria group decreased while Acidobacteria group increased markedly, compared with those in primeval forest soil.

从每种基因型中随机选择一个克隆子作为代表进行测序分析，所有序列与GenBank数据库中序列的同源性为87%~100%，且两样地中均有超过一半的基因型序列与数据库中已知序列同源性低于97%，属于分类在"种"地位上的新发现细菌；通过系统发育研究将两样地的细菌分为10大类群，两样地共同拥有5大类群，但两样地的细菌优势类群明显不同，原生土壤为Proteobacteria，含39种基因型，占总克隆子数的58.0%，退化生态系统土壤为Acidobacteria和Proteobacteria，分别含19种和15种基因型，占总克隆子数的32.5%和30.5%；与原生土壤细菌类群相比，退化生态系统土壤Proteobacteria类群明显减少，Acidobacteria类群明显增加。

System of compensation for ecological benefit of forest is a key measure ensuring sustainable development of non-industrial ecological forests.

bstract 森林生态效益补偿制度的建立是保证我国生态公益林可持续发展的关键性措施。

A system of compensation for ecological benefit of forest is a key measure ensuring sustainable development of non-industrial ecological forests.

森林生态效益补偿制度的建立是保证我国生态公益林可持续发展的关键性措施。

Public welfare forests in building forest ecosystem are possessed of nonexclusive characteristic of public goods, which leads to economic externality.

森林生态体系建设中的公益林，具有公共物品非排他性和非排斥性的特征，由此带来的外在性是市场失灵的一个重要因素，它将导致生态资源配置的长期低效。

Public welfare forests in building forest ecosystem are possessed of nonexclusive characteristic of public goods, which leads to economic externality. It is an important factor of market failures and causes law-efficient allocation of ecological resources for a long time.

森林生态体系建设中的公益林，具有公共物品非排他性和非排斥性的特征，由此带来的外在性是市场失灵的一个重要因素，它将导致生态资源配置的长期低效。

Due to the population pressure and the nonrational economic activities, the fragile karst ecological environment has become worsened, and the land rocky desertification has become one of the most serious ecological environment problems in the karst area, intimidating the survival and development of local residents.

脆弱喀斯特生态环境在人口压力和不合理经济活动作用下日益恶化，土地石漠化已成为喀斯特地区最严重的生态环境问题之一，直接威胁着当地居民的生存与发展。

The existence of biological, economic and optimum equilibrium of the system is examined.

证明了系统生态平衡点、生态经济平衡点和最适宜的平衡点的存在性。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。