primary productivity的用法和样例：
例句
- Ferns were the first terricolous vascular plants, and still comprise an important part of primary productivity of ecosystems.
蕨类植物是最早登陆的维管植物，至今仍然是生态系统初级生产力的重要组成部分。 - The results indicated that the aboveground net primary productivity of the ecosystem was more related to the dynamic changes of precipitation and temperature.
结果表明，高寒草甸净初级生产力的动态行为以对降水和气温的即时直接响应为主。
