水保所知识产出(1956---)知识库

为推进PAM 在农业生产中的实际应用，深入了解保水剂PAM 在旱地果园中的
作用和效果，确定田间应用技术参数，本研究将PAM 与尿素进行混施，通过室内土
柱试验，研究了其对土壤水分入渗、蒸发及养分淋溶的影响，通过大田果园试验，研
究了其对渭北旱塬土壤及苹果生产的影响，主要研究成果如下：
（1）采用一维垂直积水入渗法，分析了PAM 与尿素混施对土壤入渗性能的影响。
结果表明：PAM 和尿素处理，都降低了土壤的入渗能力；相对于尿素，PAM 对入渗
的抑制作用更强；随着PAM 用量的增加，入渗率、累积入渗量减小，达到稳渗所需
时间显著增加；在同一PAM 处理水平下，入渗率、累积入渗量总体上呈现随尿素用
量增加而减小的趋势，达到稳渗所需时间也有所增加，但是当PAM 用量超过0.1%时，
由尿素产生的这种差异不显著；采用Philip 入渗模型对各个处理入渗过程实测值进行
拟合，拟合效果较好，规律同上；入渗结束后，测量土柱各土层含水率，显示土壤含
水率随PAM 用量增大而增加，尿素对含水率的影响不显著。
（2）通过室内土柱模拟试验，分析了PAM 与尿素混施对土壤蒸发特性的影响。
结果表明：0~10 cm 浅层混施，在P1、P2 和P3 水平下，12 d 内尿素四个处理水平对
蒸发的影响无差异，12 d 后，差异开始逐渐凸显，总体呈现随着尿素施用量的增加蒸
发量减小的规律；在同一尿素水平下，累积蒸发量随着PAM 用量的增加而减小。
10~20cm 深层混施，在同一PAM 水平下，尿素四个处理中，N1 累积蒸发量最大；在
同一尿素水平下，累积蒸发量总体呈现随着PAM 用量的增加而减小。深施各处理土
壤总蒸发量普遍高于浅施各处理。0~10 cm 浅层混施，前5 d 日蒸发量迅速下降，5~25d
日蒸发量波动性缓慢下降，25 d 后日蒸发量趋于稳定；10~20cm 深层混施，前10 d
日蒸发量波动性保持近似水平，12 d 以后开始逐渐下降，25 d 以后又趋于稳定。总之，
PAM 和尿素处理，都抑制了土壤的蒸发；相对于尿素，PAM 对蒸发的抑制作用更强。
（3）通过室内土柱模拟试验，采用间歇淋溶法，分析了PAM 与尿素混施对土壤
养分淋溶特性的影响。结果表明：全氮淋溶量随着尿素施用量的增加而增加，并且第
一次淋溶全氮量较多，施氮量越高第一次淋溶液中全氮占总淋溶液全氮比例越高。本
研究中，只有部分处理呈现淋溶量随着PAM 施用量的增加而减小的规律，多数随着
PAM 用量的增加先增大后减小。
（4）以17 a 生富士苹果树为试材，采用二因素四水平完全随机设计，研究了PAM与尿素混施对渭北旱塬土壤及苹果树生长、产量及品质的影响，结果表明：新梢生长
量、单果重和果实横径随着尿素施用量的增加而增大，百叶重和产量随着尿素施用量
的增加先增大后减小；新梢生长量、单果重、果实横径和产量随着PAM 用量的增加
总体上表现出先增大后减小的趋势，并在P3 水平表现出最大值；果实中可溶性固形
物在P2N2 和P4N4 处理中含量较高，含酸量在P2 水平下相对较低；果园中施用的
氮肥经过一年的淋溶，100cm 深度以内，部分处理呈现出施肥量高则土层中硝态氮含
量高的规律，P2N1 和P3N2 两处理下PAM 对尿素的保蓄能力最强。在渭北旱塬苹果
园推广PAM 与尿素混施时，推荐PAM 与尿素最佳配比为P3N2，即尿素与PAM 的
质量比为6 左右。
关键词：PAM；尿素；土壤；苹果

With the purpose of promoting the practical application of PAM in agricultural field,
understanding the effect of PAM in droughty orchard, and determining the technical
parameters of field application, this study researched the effects of PAM mixed with Urea
on soil infiltration, evaporation and nutrients leaching by soil column experiment, and
studied the influence of PAM mixed with Urea on soil and apple production in Weibei
Rainfed Highland by orchard test. The main contributions are as follows:
（1）The effect of PAM mixed with Urea on soil infiltration was investigated through
one-dimensional vertical infiltration in laboratory experiment. The results showed that both
PAM and Urea inhibited soil infiltration process. The inhibition effect of PAM on soil
infiltration was greater than that of Urea. The infiltration rate and cumulative infiltration
gradually decreased with the increase of PAM amount. The time attained to stable
infiltration state was significantly lasted with the increase of PAM amount. The infiltration
rate and cumulative infiltration were decreased with the increase of Urea amount. However,
the difference caused by Urea was not significant when the ratio of PAM amount to soil
was more than 0.1%. The Philip Infiltration Model provided the best description of the
relationship between cumulative infiltration and elapsed time. Soil water content greater
with the increasing of PAM amount, thus the effect of Urea soil water content was not
significant. Therefore, PAM mixed with Urea in soil cores can reduce soil infiltration
process and deep water percolation, and increase soil moisture storage. PAM can easily
keep soil moisture and nutrients for the needs of crop growth. Thus, PAM as a reliable
material increases water and fertilizer use efficiency and reduces the effect of fertilizer
pollution on ground water. In the foregoing analysis, it would be better if PAM mixed with
fertilizer were applied to the bottom of the arable soil layer in an agricultural field. The  measurement can ensure water storage in arable soil layer, reduce deep water and nutrient
percolation, and inhibit soil evaporation.
（2）The effect of PAM mixed with Urea on soil evaporation was investigated through
soil column experiment. The results showed that when PAM and Urea were mixed using
within 10cm in the soil column, under the level of P1, P2 and P3, the effect of Urea on
evaporation was not significant at the beginning, after 12 days, the evaporation decreased
with the increase of Urea amount, besides, under the same level of Urea, the evaporation
decreased with the increase of PAM amount. When PAM and Urea were mixed using from
10cm to 20cm in the soil column, under the same level of PAM, the evaporation of N1 was
the biggest in the four levels of Urea, and under the same level of Urea, the evaporation
decreased with the increase of PAM amount. The total soil evaporation of deep application
was bigger than shallow application. Under the condition of shallow application, the daily
evaporation decreased rapidly in the first 5 days, then a slow decline in volatility from 5 to
25 days, and then tended to be stable. Under the condition of deep application, the daily
evaporation kept consistent grossly in the first 10 days, and then declined gradually, after
25days, tended to be stable. In a word, both PAM and Urea inhibited soil evaporation. The
inhibition effect of PAM on soil evaporation was greater than that of Urea.
（3）Through soil column experiment, and by spouted-spraying methods, this paper
studied the effect of PAM mixed with Urea on soil leaching. The results showed that the
leaching amount of total nitrogen increased with the increase of Urea amount, besides, the
leaching amount of the first time accounted for most of the total five leaching. In this study,
only a few treatments showed the law that the leaching amount decreased with the increase
of PAM amount, most treatments showed the leaching amount increased at first and then
decreased with the increase of PAM amount.
（4）Viewing the 17-year-old fuji apple trees as test material, using completely
randomized design with two factors and four levels to research the effects of PAM mixed
with Urea on soil and apple production in Weibei Rainfed Highland. The results showed
that: The shoot length, single fruit weight and the fruits' transect diameter increased with
the increase of Urea amount. The weight of 100 leaves and the fruit yield increased at first
then decreased with the increase of Urea amount. The shoot length, single fruit weight, the
fruits' transect diameter and the fruit yield increased at first then decreased with the  increase of PAM amount, and the maximum was present to the level P3.The soluble solids
content was higher in the treatment of P2N2 and P4N4. The acid content was lower in the
level P2. After leaching for one year, the nitrogen in the orchard soil had changed. Within
one meter, a part of treatments presented a law that the amount of nitrate nitrogen increased
with the increase of Urea amount. The retention of PAM to Urea was the strongest in the
treatments of P2N1 and P3N2. In this study, the best ratio of PAM and Urea is P3N2,
namely the mass ratio of Urea to PAM is about 6.
Key words: PAM; Urea; soil; apple