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一、世界上主要国家保护地的现状 1、保护地的类型与分布 保护地生产,是在外界环境条件不适合于植物正常的生长与发育时,用人工的办法,创造适合于植物生长发育的条件,以满足人类不断增长的经济生活的要求。保护地蔬菜生产的类型很多,大体上可以归纳为几种类型。(1)从播种到收获全部在保护地内进行,可以严格控制环境条件,缩短栽培时间,增加产量,这种设施一般称为温室;(2)在大多数情况下,只是苗期在覆盖条件下生产,然后定植于露地者称为温床;(3)用塑料薄膜做成高1
I. Status of Protected Areas in Major Countries in the World 1. Types and Distribution of Protected Areas Protected production is a method by which artificial conditions are not suitable for the normal growth and development of plants when the external environment is not suitable for the growth and development of plants Conditions to meet the requirements of mankind’s growing economic life. Protected vegetable production of many types, in general, can be grouped into several types. (1) From sowing to harvesting all in the protected area, environmental conditions can be strictly controlled, cultivation time can be shortened, and output can be increased. Such facilities are generally called greenhouses. (2) In most cases, Production, and then planted in the open field known as the hotbed; (3) made of plastic film high 1