为什么要耕地？这个问题涉及到农业生产和生态保护等多个方面，以下是基于这个问题的解析以及英文翻译对照：

首先，耕地是农业生产的基础。农业生产是指利用植物、动物和微生物等生物体来生产人类所需的食品、饲料、医药品和工业原料等物质。耕地是指经过翻耕、犁耕等农业活动而使土壤松软、土地平整、灌溉和水源充足，适合作物生长的田地。只有当土地经过耕整、疏松、平整、施肥等农业活动后，才能为农作物提供足够的养分和适宜的生长环境，从而提高农作物的产量和质量。英文翻译为: Why is farmland necessary? This question involves multiple aspects such as agricultural production and ecological protection. The following are the reasons and their English translations:

Firstly, farmland is the foundation of agricultural production. Agricultural production refers to the use of plants, animals, and microorganisms to produce foods, feed, medicine, and industrial raw materials for human use. Farmland refers to land that has been turned and flattened by agricultural activities such as plowing and harrowing, with sufficient irrigation and water sources suitable for crop growth. Only after the land undergoes agricultural activities such as fertilization, soil loosening, leveling, and watering can it provide enough nutrients and a suitable living environment for crops to achieve high yields and quality.

其次，耕地是保障国家粮食安全的重要手段。粮食是人类生存和发展的基础，而耕地则是保障粮食生产的重要手段。只有通过耕整、疏松、平整、施肥等农业活动，才能使土地保持肥力和生产力，为农作物提供足够的养分和适宜的生长环境，从而提高农作物的产量和质量，为国家粮食安全提供保障。英文翻译为: Secondly, farmland is an important means to ensure national food security. Food is the foundation of human survival and development, and farmland is an important means to ensure food production. Only through agricultural activities such as fertilization, soil loosening, leveling, and watering can land maintain its fertility and productivity, providing enough nutrients and a suitable living environment for crops to achieve high yields and quality, thereby ensuring national food security.