不同水氮管理下日光温室黄瓜季氮素淋失研究
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摘要
我国是蔬菜种植大国,更是蔬菜消费、出口大国。为了满足不断增长的蔬菜需求,日光温室发展迅速,成为世界上设施栽培面积最大的国家。由于受到传统蔬菜种植模式的影响,我国当前蔬菜生产体系中普遍存在着大水漫灌和过量施肥的不科学种植方式,直接导致水氮资源的浪费和环境污染问题,这成为制约设施蔬菜可持续发展的关键因素。因此,研究不同水氮管理下日光温室黄瓜季生育期氮素淋失对于日光温室氮的科学利用具有重要意义。针对日光温室蔬菜种植过程中不同水氮条件下土壤中无机氮淋失的问题,在河北省辛集市马庄农场日光温室内设置分区不同处理田间试验,系统、科学的研究不同水氮管理下保护地冬春季黄瓜种植过程中土壤无机氮损失规律及对黄瓜产量和品质的影响。本研究以河北地区辛集科园农场为试验基地,通过设计2个灌水水平下的不同施氮(尿素)处理,对黄瓜季重要生育期进行土壤无机氮淋失进行研究,探讨不同水氮处理对黄瓜产量、植株干物质积累以及氮利用率的影响,从而提出最佳水氮管理模式。主要研究结论如下：
1.灌水量增高,各土层的土壤含水量就相对越高。相比传统灌水处理(W1),节水灌溉处理(W2)在一定程度上降低了整个生育期的土壤含水量水平,这在苗期和初瓜期表现尤为明显。节水灌溉处理使黄瓜生育期0～40cm土层土壤含水量保持在20.0%左右,节水灌溉处理(W2)可以满足作物各个生育期正常生长水分需要,而节水效果明显。
2.相同灌水量下,随施氮量增加,各土层的硝态氮含量增加。减量施氮处理的土壤硝态氮累积量相比习惯施氮处理减少了18.0%～50.8%。而不施氮的两个处理其硝态氮含量一直维持在较低水平。
相同施氮量下,随灌水量增大,各土层土壤硝态氮含量有所降低。说明传统灌水更容易导致硝态氮的向深层流失。随着作物生长时间的延长及施肥次数的增加,各施氮处理的95cm土层深度土壤溶液硝态氮含量是平稳上升的。
所有施氮处理中,W2N600(节水灌溉下的减氮50%处理)处理土壤硝态氮含量平均水平最低。因此推荐水氮管理W2N600(节水灌溉下的减氮50%处理)能够降低土壤硝态氮含量。
3.相同施氮量中,习惯灌水处理的硝态氮淋失量明显高于减量灌水的硝态氮累积淋失量,其中W1N1200(习惯灌溉下的习惯施氮处理)比W2N1200(节水灌溉下的习惯施氮处理)增加了34.7%,W1N900(习惯灌溉下的减氮25%处理)比W2N900(习惯灌溉下的习惯施氮处理)增加了24.1%。这说明加大灌水量会明显增加硝态氮的整个生育期硝态氮淋失量,不施氮处理的硝态氮累积淋失量相比施氮处理明显降低。
相同灌水量下,减量施氮处理能减少硝态氮淋失量。在苗期、初瓜期、盛瓜期、末瓜期W1N1900处理比W1N1200处理硝态氮淋失量分别降低了23.1%、22.0%、20.5%、11.2%。
W2N600处理比W1N1200处理硝态氮淋失量分别降低了68.2%、61.6%、54.8%、46.0%,整个黄瓜生育期,节水灌溉、减量50%施氮处理(W2N600)比习惯水氮处理(W1N1200)硝态氮淋失量降低了57.8%。
所有施氮处理中,以W2N600(节水灌溉下的减氮50%处理)处理的硝态氮累积淋失量最低,为184.3kg/hm2。
4.黄瓜全生育期在95cm深度土壤含水量和硝态氮淋失量呈正相关,在1200kg/hm2施氮水平下,两者在盛瓜期呈显著相关；在900kg/hm2施氮水平下,在初瓜期、盛瓜期和末瓜期95cm深度土壤含水量和硝态氮淋失量呈线性显著相关。W2N600处理下,整个生长期都达到显著水平。一定施氮下,土壤含水量能显著影响硝态氮的淋失量,1200kg/hm2和900kg/hm2施氮水平下,以盛瓜期相关性系数最高。
在黄瓜生长全生育期内土壤剖面95cm深度硝态氮淋失量随着土壤硝态氮含量增加而增加,土壤硝态氮含量与硝态氮淋失量呈线性正相关。在初瓜期、盛瓜期、末瓜期内土壤硝态氮含量与硝态氮淋失量线性相关达到显著水平且以盛瓜期相关系数最高。
5.同一灌水量下,随着施氮量的增加,氮肥利用率逐渐降低。在所有处理中W2N600的氮素表观利用率最高。
6.2008年W2N600处理黄瓜产量最高,与农民传统水氮管理W1N1200相比,2008年、2009年和2010年W2N600处理黄瓜产量未出现显著降低,比农民传统水氮管理节氮50%节水30%左右,黄瓜产量未出现显著降低。
综上所述,本试验条件下,在减少用水30%、减施氮肥25%-50%的处理能够显著降低硝态氮淋洗量35.0%～57.8%,而黄瓜产量没有显著降低,氮肥利用率提高了4.92%～16.02%。氮素表观利用率提高了21.3%～27.3%。W2N600处理(节水灌溉下的减氮50%处理)在节水30%、减氮50%的条件下完全能够保证作物产量的稳定,为推荐水氮管理模式。
Our country is power in the vegetable planting, but also vegetable consumption and export power. To meet the increasing demand of vegetables, sunlight greenhouse developing rapidly, China has become the world's largest country facility culture area. Due to the influence of the traditional vegetable planting mode, there is a widespread use of water and fertilizer plant of excessive way in our current vegetable production system, it lead to the water and nitrogen waste of resources and environmental pollution, become the main facilities vegetables the key to the sustainable development of factors. Therefore, the study of leaching nitrogen of cucumber season growth period in sunlight greenhouse under different water and nitrogen management have the important meaning for sunlight greenhouse of nitrogen use science. To solve the problem of soil nitrogen leaching in sunlight greenhouse in the effects of different water and nitrogen amounts, set up different processing field experiment in a greenhouse in Xinji, Hebei province in2010, for the research of effects of different water and nitrogen management on nitrate leaching in sunlight greenhouse and the yields during cucumber growing season. The study was conducted in Xinji, Hebei province, design different nitrogen (urea) processing under two level of water, study nitrate nitrogen leaching during cucumber growing season to determine the effects of water and nitrogen management on yields, dry matter accumulation and nitrogen utilization, we can finally get the best water and nitrogen management mode. The main results were as follows:
1. With the increase of irrigation water, the value of soil moisture content rise. The water-saving treatments reduce the soil moisture content in the whole period with the conventional water treatment, especially in seeding stage and primary fruit stage. The water-saving treatment which maintains soil moisture contents at about20%in the whole period can meet the demand of water for cucumber growth, the treatment can save water30%with the conventional water treatment.
2. The same irrigation water, with the increase of nitrogen, the values of soil nitrate nitrogen contents were increased. The treatment with25%～50%reduction in nitrogen can reduce soil nitrate nitrogen contents by18.0～50.8%. The soil nitrate nitrogen contents maintain at low levels.
The same nitrogen used, with the increase of irrigation water, the values of soil nitrate nitrogen contents were reduced. It show that it's easy to cause soil nitrate nitrogen into deep soils. The value of soil nitrate nitrogen contents of95cm depth in soil is rising steadily along with the growth of the crop and the increase of number of fertilization.
All treatments of nitrogen used, the treatment is W2N600with30%reduction in water and50%reduction in nitrogen in soil nitrate nitrogen contents. It's therefore the treatment W2N600was the recommend treatment which can reduce the soil nitrate nitrogen contents.
3. The same nitrogen used, with the increase of irrigation water, the values of nitrate nitrogen contents leaching amount were increasing. The value of W1N1200(the conventional treament) increased by34.7%than W2N1200(30%reduction in water, conventional nitrogen); The value of W1N900(conventional water,25%reduction in nitrogen) increased by24.1%than W2N900(30%reduction in water,25%reduction in nitrogen). The nitrate nitrogen contents leaching amount was increasing with the increasing of irrigation water. They are stay at low level wtth no nitrogen used.
The same irrigation water, with the reduce of nitrogen, the values of the nitrate nitrogen leaching amount were reduced. At seeding stage、 primary fruit stage、 full fruit stage、 last fruit stage, The value of W1N900(conventional water,25%reduction in nitrogen) respectively reduced by23.1%、22.0%、20.5%、11.2%than W1N1200(the conventional treament). The value of W2N600(30%reduction in water,50%reduction in nitrogen) respectively reduced by68.2%、61.6%、54.8%、46.0%than W|N|200(the conventional treament). The nitrate nitrogen leaching amount of W2N600(30%reduction in water,50%reduction in nitrogen) is reduced by57.8%in the whole period. The lowest values of nitrate nitrogen leaching amount is184.3kg/hm2, the processing is W2N600(30%reduction in water,50%reduction in nitrogen)
4. The nitrate nitrogen leaching amount in the depth of95cm is closely related to soil moisture during cucumber growing season, especially of the full fruit stage under1200kg/hm" nitrogen treatment and the seeding stage、 full fruit stage、 last fruit stage under900kg/hm" nitrogen treatment. With certain nitrogen amount, the soil moisture can significantly affect the nitrate nitrogen leaching amount, especially of the full fruit stage.
The nitrate nitrogen leaching amount increase with the soil nitrate nitrogen contents in the depth of95cm during cucumber growing season, they are linear positive correlation. The nitrate nitrogen leaching amount in the depth of95cm is closely related to soil nitrate nitrogen contents during primary fruit stage、 full fruit stage、 last fruit stage, the highest values was in full fruit stage.
5. The same irrigation water, with the increase of nitrogen amount, the loss of nitrogen was increased, the utilization of nitrogen was reduced. In all processing, the utilization of nitrogen with the treatment W2N600was top.
6. The yields of treatments W2N600was the highest compared with the conventional treatment in2008. But, the yields of W2N600with30%reduction in water and50%reduction in nitrogen have no significantly reduced with the conventional treatment in2009、2010.
In conclusion, the treatment W2N600was much more reasonable management approach. Because this treatment with30%reduction in water and50%reduction in nitrogen can make the nitrate nitrogen leaching amount reduced by35.0%-57.8%in the whole period without the yields'reduce. The treatment W2N600can increase the utilization of nitrogen and reduce the nitrate nitrogen leaching amounts compared with the conventional treatment. So, the treatment W2N600with30%reduction in water and50%reduction in nitrogen was the best management approach.
1.灌水量增高,各土层的土壤含水量就相对越高。相比传统灌水处理(W1),节水灌溉处理(W2)在一定程度上降低了整个生育期的土壤含水量水平,这在苗期和初瓜期表现尤为明显。节水灌溉处理使黄瓜生育期0～40cm土层土壤含水量保持在20.0%左右,节水灌溉处理(W2)可以满足作物各个生育期正常生长水分需要,而节水效果明显。
2.相同灌水量下,随施氮量增加,各土层的硝态氮含量增加。减量施氮处理的土壤硝态氮累积量相比习惯施氮处理减少了18.0%～50.8%。而不施氮的两个处理其硝态氮含量一直维持在较低水平。
相同施氮量下,随灌水量增大,各土层土壤硝态氮含量有所降低。说明传统灌水更容易导致硝态氮的向深层流失。随着作物生长时间的延长及施肥次数的增加,各施氮处理的95cm土层深度土壤溶液硝态氮含量是平稳上升的。
所有施氮处理中,W2N600(节水灌溉下的减氮50%处理)处理土壤硝态氮含量平均水平最低。因此推荐水氮管理W2N600(节水灌溉下的减氮50%处理)能够降低土壤硝态氮含量。
3.相同施氮量中,习惯灌水处理的硝态氮淋失量明显高于减量灌水的硝态氮累积淋失量,其中W1N1200(习惯灌溉下的习惯施氮处理)比W2N1200(节水灌溉下的习惯施氮处理)增加了34.7%,W1N900(习惯灌溉下的减氮25%处理)比W2N900(习惯灌溉下的习惯施氮处理)增加了24.1%。这说明加大灌水量会明显增加硝态氮的整个生育期硝态氮淋失量,不施氮处理的硝态氮累积淋失量相比施氮处理明显降低。
相同灌水量下,减量施氮处理能减少硝态氮淋失量。在苗期、初瓜期、盛瓜期、末瓜期W1N1900处理比W1N1200处理硝态氮淋失量分别降低了23.1%、22.0%、20.5%、11.2%。
W2N600处理比W1N1200处理硝态氮淋失量分别降低了68.2%、61.6%、54.8%、46.0%,整个黄瓜生育期,节水灌溉、减量50%施氮处理(W2N600)比习惯水氮处理(W1N1200)硝态氮淋失量降低了57.8%。
所有施氮处理中,以W2N600(节水灌溉下的减氮50%处理)处理的硝态氮累积淋失量最低,为184.3kg/hm2。
4.黄瓜全生育期在95cm深度土壤含水量和硝态氮淋失量呈正相关,在1200kg/hm2施氮水平下,两者在盛瓜期呈显著相关；在900kg/hm2施氮水平下,在初瓜期、盛瓜期和末瓜期95cm深度土壤含水量和硝态氮淋失量呈线性显著相关。W2N600处理下,整个生长期都达到显著水平。一定施氮下,土壤含水量能显著影响硝态氮的淋失量,1200kg/hm2和900kg/hm2施氮水平下,以盛瓜期相关性系数最高。
在黄瓜生长全生育期内土壤剖面95cm深度硝态氮淋失量随着土壤硝态氮含量增加而增加,土壤硝态氮含量与硝态氮淋失量呈线性正相关。在初瓜期、盛瓜期、末瓜期内土壤硝态氮含量与硝态氮淋失量线性相关达到显著水平且以盛瓜期相关系数最高。
5.同一灌水量下,随着施氮量的增加,氮肥利用率逐渐降低。在所有处理中W2N600的氮素表观利用率最高。
6.2008年W2N600处理黄瓜产量最高,与农民传统水氮管理W1N1200相比,2008年、2009年和2010年W2N600处理黄瓜产量未出现显著降低,比农民传统水氮管理节氮50%节水30%左右,黄瓜产量未出现显著降低。
综上所述,本试验条件下,在减少用水30%、减施氮肥25%-50%的处理能够显著降低硝态氮淋洗量35.0%～57.8%,而黄瓜产量没有显著降低,氮肥利用率提高了4.92%～16.02%。氮素表观利用率提高了21.3%～27.3%。W2N600处理(节水灌溉下的减氮50%处理)在节水30%、减氮50%的条件下完全能够保证作物产量的稳定,为推荐水氮管理模式。
Our country is power in the vegetable planting, but also vegetable consumption and export power. To meet the increasing demand of vegetables, sunlight greenhouse developing rapidly, China has become the world's largest country facility culture area. Due to the influence of the traditional vegetable planting mode, there is a widespread use of water and fertilizer plant of excessive way in our current vegetable production system, it lead to the water and nitrogen waste of resources and environmental pollution, become the main facilities vegetables the key to the sustainable development of factors. Therefore, the study of leaching nitrogen of cucumber season growth period in sunlight greenhouse under different water and nitrogen management have the important meaning for sunlight greenhouse of nitrogen use science. To solve the problem of soil nitrogen leaching in sunlight greenhouse in the effects of different water and nitrogen amounts, set up different processing field experiment in a greenhouse in Xinji, Hebei province in2010, for the research of effects of different water and nitrogen management on nitrate leaching in sunlight greenhouse and the yields during cucumber growing season. The study was conducted in Xinji, Hebei province, design different nitrogen (urea) processing under two level of water, study nitrate nitrogen leaching during cucumber growing season to determine the effects of water and nitrogen management on yields, dry matter accumulation and nitrogen utilization, we can finally get the best water and nitrogen management mode. The main results were as follows:
1. With the increase of irrigation water, the value of soil moisture content rise. The water-saving treatments reduce the soil moisture content in the whole period with the conventional water treatment, especially in seeding stage and primary fruit stage. The water-saving treatment which maintains soil moisture contents at about20%in the whole period can meet the demand of water for cucumber growth, the treatment can save water30%with the conventional water treatment.
2. The same irrigation water, with the increase of nitrogen, the values of soil nitrate nitrogen contents were increased. The treatment with25%～50%reduction in nitrogen can reduce soil nitrate nitrogen contents by18.0～50.8%. The soil nitrate nitrogen contents maintain at low levels.
The same nitrogen used, with the increase of irrigation water, the values of soil nitrate nitrogen contents were reduced. It show that it's easy to cause soil nitrate nitrogen into deep soils. The value of soil nitrate nitrogen contents of95cm depth in soil is rising steadily along with the growth of the crop and the increase of number of fertilization.
All treatments of nitrogen used, the treatment is W2N600with30%reduction in water and50%reduction in nitrogen in soil nitrate nitrogen contents. It's therefore the treatment W2N600was the recommend treatment which can reduce the soil nitrate nitrogen contents.
3. The same nitrogen used, with the increase of irrigation water, the values of nitrate nitrogen contents leaching amount were increasing. The value of W1N1200(the conventional treament) increased by34.7%than W2N1200(30%reduction in water, conventional nitrogen); The value of W1N900(conventional water,25%reduction in nitrogen) increased by24.1%than W2N900(30%reduction in water,25%reduction in nitrogen). The nitrate nitrogen contents leaching amount was increasing with the increasing of irrigation water. They are stay at low level wtth no nitrogen used.
The same irrigation water, with the reduce of nitrogen, the values of the nitrate nitrogen leaching amount were reduced. At seeding stage、 primary fruit stage、 full fruit stage、 last fruit stage, The value of W1N900(conventional water,25%reduction in nitrogen) respectively reduced by23.1%、22.0%、20.5%、11.2%than W1N1200(the conventional treament). The value of W2N600(30%reduction in water,50%reduction in nitrogen) respectively reduced by68.2%、61.6%、54.8%、46.0%than W|N|200(the conventional treament). The nitrate nitrogen leaching amount of W2N600(30%reduction in water,50%reduction in nitrogen) is reduced by57.8%in the whole period. The lowest values of nitrate nitrogen leaching amount is184.3kg/hm2, the processing is W2N600(30%reduction in water,50%reduction in nitrogen)
4. The nitrate nitrogen leaching amount in the depth of95cm is closely related to soil moisture during cucumber growing season, especially of the full fruit stage under1200kg/hm" nitrogen treatment and the seeding stage、 full fruit stage、 last fruit stage under900kg/hm" nitrogen treatment. With certain nitrogen amount, the soil moisture can significantly affect the nitrate nitrogen leaching amount, especially of the full fruit stage.
The nitrate nitrogen leaching amount increase with the soil nitrate nitrogen contents in the depth of95cm during cucumber growing season, they are linear positive correlation. The nitrate nitrogen leaching amount in the depth of95cm is closely related to soil nitrate nitrogen contents during primary fruit stage、 full fruit stage、 last fruit stage, the highest values was in full fruit stage.
5. The same irrigation water, with the increase of nitrogen amount, the loss of nitrogen was increased, the utilization of nitrogen was reduced. In all processing, the utilization of nitrogen with the treatment W2N600was top.
6. The yields of treatments W2N600was the highest compared with the conventional treatment in2008. But, the yields of W2N600with30%reduction in water and50%reduction in nitrogen have no significantly reduced with the conventional treatment in2009、2010.
In conclusion, the treatment W2N600was much more reasonable management approach. Because this treatment with30%reduction in water and50%reduction in nitrogen can make the nitrate nitrogen leaching amount reduced by35.0%-57.8%in the whole period without the yields'reduce. The treatment W2N600can increase the utilization of nitrogen and reduce the nitrate nitrogen leaching amounts compared with the conventional treatment. So, the treatment W2N600with30%reduction in water and50%reduction in nitrogen was the best management approach.
引文
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