论文部分内容阅读
【目的】明确小农户经营模式下小麦施肥现状,为实现旱地小麦稳产增产和养分高效利用提供依据。【方法】通过连续5年对渭北旱地1 261个农户的养分管理调研,以维持旱地小麦可持续生产为出发点,基于小麦产量确定的养分需求量,评价农户施肥量,分析农户施肥的问题及减肥潜力。【结果】调研农户小麦籽粒产量介于750—9 000 kg·hm~(-2),平均4 243 kg·hm~(-2),属于低产(<2 640 kg·hm~(-2)),偏低(2 640—3 780 kg·hm~(-2)),中产(3 780—4 920 kg·hm~(-2)),偏高(4 920—6 060 kg·hm~(-2)),高产(>6 060 kg·hm~(-2))等级的农户依次占22.0%,22.2%,19.3%,22.8%,13.6%。农户氮肥用量介于33—454 kg N·hm~(-2),平均188 kg N·hm~(-2);磷肥介于0—435 kg P_2O_5·hm~(-2),平均125 kg P_2O_5·hm~(-2);钾肥介于0—201 kg K_2O·hm~(-2),平均19 kg K_2O·hm~(-2),农户的施氮、磷和钾量均与小麦产量无显著相关关系。从低产到高产,施氮过量(偏高+很高)的农户比例逐渐降低,由97.8%降低到18.0%;而施氮不足(偏低+很低)的农户逐渐增多,由0.7%增加到45.9%。与氮肥类似,随着产量水平提高,施磷过量的农户比例也逐渐降低,但降低幅度小,由99.3%仅降低到70.9%,即过量施磷普遍存在。与氮、磷不同,在各产量水平下至少有60%的农户施钾不足。因此,在低产、产量偏低水平,重点是施氮量偏高或很高的农户需减肥,减幅在24—144 kg N·hm~(-2)、28%—73%氮肥;在中产、偏高和高产水平,既有减肥,也有增肥,减肥的重点是施氮量偏高或很高的农户,减幅在50—181 kg N·hm~(-2)、26%—51%氮肥,增肥的重点是施氮量偏低或很低的农户,增幅在38—134 kg N hm~(-2)、41%—345%氮肥。针对农户普遍施磷过量的问题,在不同产量水平,施磷量偏高的农户应减少7—31 kg P_2O_5·hm~(-2)、23%—33%的磷肥投入;施磷很高的农户应减少85—118 kg P_2O_5·hm~(-2),61%—85%的磷肥投入。由于钾肥用量普遍不足,施钾很低或不施的农户首先应改变不施钾肥的习惯,根据不同产量水平施用钾肥13—50 kg K_2O·hm~(-2);施钾偏低的农户,应增加7—18 kg K_2O·hm~(-2)、35%—78%的钾肥。【结论】相比于传统的施肥评价中用统一的施肥量标准去评价不同产量水平的农户施肥,本文提出了基于产量的农户施肥评价和减肥潜力分析方法,适于目前中国小农户农田经营模式,可以客观、准确认识目前农户随意和过量施肥的问题,为进行有效调控施肥提供依据。
【Objective】 The current status of wheat fertilization in small-scale peasant households was clarified, which provided the basis for stable yield increase and efficient use of nutrients in dryland wheat. 【Method】 Based on the investigation of nutrient management of 1 261 farmer households in Weibei dryland in five consecutive years, in order to maintain sustainable production of wheat in dryland, based on the demand of nutrients determined by wheat yield, Weight loss potential. 【Result】 The results showed that the grain yield of the surveyed farmers was between 750-9 000 kg · hm -2 and average 4 243 kg · hm -2, which was a low yield (<2 640 kg · hm -2) (2 640-3 780 kg · hm -2), middle type (3 780-4 920 kg · hm -2) and high level (4 920-6 060 kg · hm -2) 2), and those with high yield (> 6 060 kg · hm -2) ranked 22.0%, 22.2%, 19.3%, 22.8% and 13.6% in turn. The amount of nitrogen fertilizer used by peasant households ranged from 33-454 kg N · hm -2, with an average of 188 kg N · hm -2. Phosphate fertilizer ranged from 0-435 kg P 2 O 5 · hm -2 with an average of 125 kg P 2 O 5 · Hm ~ (-2); Potash fertilizer ranged from 0-201 kg K_2O · hm -2, with an average of 19 kg K_2O · hm -2. The N, P, Significantly related. From low-yielding to high-yielding, the proportion of peasant households with excess nitrogen (high + high) decreased gradually from 97.8% to 18.0%; while those with low (low + low) nitrogen application increased gradually from 0.7% to 45.9%. Similar to nitrogen fertilizer, with the increase of production level, the proportion of peasants that overdosed with phosphorus decreased gradually, but the decrease ranged from 99.3% to 70.9%, that is, excess phosphorus was ubiquitous. Unlike nitrogen and phosphorus, at least 60% of farmers at each production level are under-fertilized. Therefore, in low-yielding and low-yielding areas, the emphasis is on farmers with high or very high N rates to reduce their diets by 24-144 kg N · hm -2, 28% -73% nitrogen fertilizers; , High and high yield level, both weight loss and weight gain. The key point of weight loss is that farmers with high or very high nitrogen application rate are in the range of 50-181 kg N · hm -2, 26% -51 % Nitrogen fertilizer, the key point of fertilizer increase is that farmers with low or very low nitrogen application rate increase 38-134 kgN hm -2, 41% -345% nitrogen fertilizer. In view of the problem of over-fertilization of phosphorus by farmer households, farmers with high phosphorus application rates should reduce the input of phosphate fertilizer by 7-31 kg P 2 O 5 · hm -2 and 23% -33% at different yield levels. Farmers should reduce 85-118 kg P_2O_5 · hm -2, 61% -85% of the phosphate fertilizer input. Due to the generally insufficient amount of potash fertilizer, farmers applying low or no K fertilizer should first change the habit of not applying K fertilizer, and apply 13-50 kg K 2 O · hm -2 of K fertilizer according to different yield levels; Should increase 7-18 kg K_2O · hm ~ (-2), 35% -78% of potash. 【Conclusion】 Compared with the traditional fertilization evaluation, the uniform fertilization rate was used to evaluate the fertilization rate of farmers at different yield levels. This paper proposed a method of fertilization evaluation and weight loss potential analysis based on yield, which is suitable for the current small-scale farmland management mode , We can objectively and accurately understand the current problems of random and over-fertilization of farmer households and provide the basis for effective regulation and fertilization.