农田粮一菜轮作体系的生产效益与土壤养分特征

Production Efficiency and Soil Nutrient Characteristics in Food一Vegetable Rotation Systems

为关中平原地区探索、选择优化合理的农田轮作组合,在"商品经济"背景下以提高农民收入为目的的农业结构与作物布局调整提供参考。依据系统的田间定位试验数据,对关中平原常见的粮食作物小麦、玉米和蔬菜作物大蒜、辣椒、茄子、芹菜组成的不同轮作体系的经济产值、土地当量比、生物产量、经济系数、农田土壤环境效应进行了分析。结果表明:(1)就经济效益和土地产出效率而言,小麦和玉米组成的粮—粮轮作体系经济效益和土地产出效率是7种轮作体系中最低的,而由大蒜和辣椒、茄子、芹菜组成的蔬菜—蔬菜体系效益和土地产出效率最佳。(2)从生态学角度分析,大蒜和辣椒、茄子、芹菜组成的各个蔬菜—蔬菜体系生物产量较高,其次是小麦和玉米组成的粮—粮轮作体系,小麦和辣椒、茄子、芹菜组成的各个粮食—蔬菜体系生物产量较低。蔬菜—蔬菜轮作体系的有机物向人类所需品的转化率相对较高,其次是粮食—蔬菜轮作体系,小麦玉米粮-粮轮作体系转化率相对较低。(3)从土壤环境效应角度分析,基础养分基本表现为蔬菜—粮食轮作体系高于蔬菜—蔬菜轮作体系,传统的粮食轮作体系相对最低。各轮作体系的土壤呼吸速率,除了大蒜—辣椒体系较大之外,其余均表现为粮食—蔬菜轮作体系高于蔬菜—蔬菜轮作体系和粮食轮作体系。依据不同角度对几种轮作体系的生产效益、土壤环境效应的评估以及对关中平原地理、经济环境实际状况的调查,粮食—蔬菜轮作模式适宜引入大田轮作生产。就本研究的几种粮食—蔬菜轮作模式而言,小麦—辣椒轮作和小麦—茄子轮作模式有较好的种植前景。

In order to provide references for adjustments of agricultural structures and crop arrangements,which aim to improve farmers＇ income within a commodity economy,optimal combinations of crop rotation are needed for agricultural development in Guanzhong plain.According to field test data,the economic value,land equivalent ratio（LRE）,biological yield,economic coefficient and the effects of rotation on soil nutrients were analyzed in different rotation systems.The crops tested included food crops of wheat（Triticum aestivum） and corn（Zea mays）,and vegetables of garlic（Allium sativum）,pepper（Capsicum）,eggplant（Solanum melongena） and celery（Apium graveolens）,which are commonly found in the plain.The results show that the terms of economic benefits and land production efficiency,the rotation system of wheat-maize was the worst one while the vegetables—vegetable rotation systems of garlic—pepper,garlic—eggplant,garlic—celery were the superior ones.From the ecological point of view focusing on biological yield and net organic yield,the value of wheat—maize was lower than the values of the vegetable—vegetable systems of garlic—pepper,garlic—eggplant,and garlic—celery,and was higher than the values of the crop—vegetable systems of wheat—pepper,wheat—eggplant,and wheat—celery.In the terms of effects on soil available nutrients and soil respiration rates,the crop—vegetable systems were better than the vegetable—vegetable rotation systems and the traditional crop rotation systems.Considering the values,geographic conditions and economic environments,the crop—vegetable rotation systems were suitable for the plain.As for the trials of this study,the rotation modes of wheat—pepper and wheat—eggplant were promising with a comprehensive consideration.