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作 者 ：周艺敏;小仓宽典

期 刊 ：植物营养与肥料学报 1997年 3卷 4期 页码：315-322

关键词：半干旱地区；菜园土壤；肥力特征；

摘 要 ：本文通过对天津地区有代表性的200多个不同种植年限菜园土壤耕层及典型剖面调查研究表明:老菜园土壤具有良好的主体构造，熟化层深厚，三相比协调、呈团粒结构，土壤微团聚体形状圆润、表面粗糙、联结疏松;新开发菜田微团聚体之间联结很紧，孔隙少，边缘整齐，彼此不沟通。老菜园土壤养分富集明显，富集特点为速效P＞全N＞OM＞全P＞速效K＞速效N。全量分析与粘土矿物显示，烧失量、CaO整个主体高于对照2～3倍;MgO、MnO、Al₂O₃、Fe₂O₃、P₂O₅高于对照20％～60％;SiO₂、Na₂O下降20％～40％;TiO₂、K₂O变化不大。菜园土壤整个主体与对照比较矿物组成变化不大;土壤微生物丰富，细菌、真菌高于对照2～3倍，放线菌高于对照1倍以上;土壤酶活性强，4种土壤酶活性高于对照2～5倍。不同发育年限菜园土壤微生物区系变化趋向显示，老菜园土壤细菌、放线菌数量增多，真菌数量有减少倾向。用土壤养分状况系统研究法对11种营养元素丰缺诊断表明，老菜园土壤养分限制因子很少，限制因子位序N＞K＞Mn，无肥区相对产量为70％以上;新菜田土壤养分限制因子很多，无肥区相对产量仅20％以上，限制因子位序P＞N＞K＞Zn＞Fe＞Mn＞S，揭示了半干旱地区菜园土壤的肥力特征，为菜园土壤持续利用提供了一定依据。

Abstract:The characteristics of vegetable soils was lnvestigated through surveylng 200 different growth year vegetable soil samples and typical representative soil profiles in Tianjin area. It was found that old vegetable soil has good soil structure, thick arable level and maturation level, good proportion of three phases. It was observed through scanning electro microscope that microaggregate of soil is round, the surface is coarse, the bonds among them are loose, and has more pores compared to the new cultivated vegetable soils whose microaggregate has a tighter bonds among them, less pores,smoother surface and has no interrelated channels each other. The nutrient accumulation in soil arable level is obvious, the characteristic of accumulation is readily availible P>total N>OM>total P>readily availible N, and soil total potassium difference is not obvious. The distribution of nutrients in soil profiles showed the characteristic of deep level accumulation of nutrients, the order of accumulation ls approximately same with the arable level. The analytical results of soll total elements and clay minerals showed that ignition loss and Cao content of total soil body is twice or three times higher than.that of control treatment; the content of MgO, MnO, Al₂O₃, Fe₂O₃, P₂O₅ is 20%-60% higher and the cohtent of SiO₂. Na₂O is 2O%~4O% lower than that of control;the content of TiO₂. K₂O has almost no change. The total vegetable soil body mainly comprises of water-mica along with some quartz. mont morillolite and a little kaolonite.The mineral composition of the total soil body has .no change compared to the control treatment. Bacterias and fungi in soils are 2~3 times higher and actinomycetaceae is one time higher than control; soil enzyme activity is high, the activity of enzyme in 4 soils is 2-5 times higher than that of control. The changing trends of microflora in vegetable soils of different development ages showed that old vegetable soil has a trend that amount of bacteria, actinomycetaceae is more and amount of fungi is less. The diagnostic results of eleven nutrients abundance/ deficiency by using method of soil nutrients systematic approach indicated that in old vegetable soils, the order of limiting factors is N>K>P>Mn, the relative yield in no fertilizer plot reached over 70%, in new vegetabie solls, the order of limiting factors is P>N>K>Zn>Fe>Mn>S, the relative yield in no fertilizer plot reached only over 20%. There is a great difference in vegetable yield and productivity due to the different soil fertility. It‘s an urgent need to improve fertility of new cultivated vegetable fields for high yielding, good qualities, and high efficiency of vegetable production.

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