关键词: 番茄, 氮肥, 养分吸收, 钙肥

Abstract: Forest divisions system, forestry divisions system and forest site types system are three main spatial management systems of China’s forestry sector, which have played key roles in the sector management traditionally focused on timber production. Forest divisions system is the most important system of organizing forestry production. The function of forestry divisions system, in essence, is to guide the production of China’ five-forest-category in different administrative zones. And, forest site types system is designed for evaluation purpose on the basis of topographic and soil factors. However, through analyzing the features and problems of the systems, the authors concluded that these systems can not effectively guide China’s future forest management that will focus more on sustainable and ecological use of forest resource instead of pure timber use, because these systems were basically timber-use-orientated and were not set up on explicit and scientific ecological principles when first designed. Innovation in this regard is very necessary and landscape approach of land classification(also used by other terms such as ecological land classification or just ecological classification system, the meaning of which are the same)was a good alternative. The alternative approach will be a bottom-up system, taking ecological system perception, applying landscape ecology principles and having clear ecological implications. The fixed cost of establishing such a new frame is very high. But in the long run, marginal cost of forestry sector management, especailly when taking all kinds of ecological factors into account, will be much lower than that of using old systems.

Key words: Tomato, Nitrogen fertilizer, Nutrient uptake, Calcium fertilizer