【作者】 缪宏超；

【导师】 黄晨；

【作者基本信息】 安徽农业大学 ， 特种经济动物饲养， 2008， 硕士

【摘要】 自70年代末我国从日本引进地膜覆盖技术以来,地膜在我国获得了迅速的发展。目前在我国地膜覆盖面积约在1400万公顷以上,用量已达100多万吨。预计到2010年,全国地膜覆盖面积将超过2000万公顷。由于目前使用的大多数地膜为聚乙烯或聚氯乙烯地膜,不易降解,并且具有毒性,残留在土壤中的碎片不能被土壤微生物降解,也不能被作物吸收利用。在我国农村,每年都有大量的秸秆产生,农民通常都是用焚烧的办法处理这些秸秆,但大量的焚烧带来了空气污染,严重影响了环境。本研究主要利用秸秆提取纤维并用非织造技术生产农用地膜,讨论了无污染、全降解地膜的原料选取、配比方案及对田间性能的测试,综合分析得出最佳方案为:废丝量为4.02g/m~2,平方米克重为80g/m~2,粘合剂浓度为8%。制成的样品主要性能为:横向断裂强度为35N,纵向断裂强度为32N,厚度为0.2641mm,透湿率为2346 g/m~2h,回潮率为5.6%。将以上地膜进行田间覆盖实验,并与普通塑料地膜进行对比。保温试验表明,天然纤维非织造地膜有较好的保温性,略低于塑料地膜。进行土壤保温性能的实验表明,天然非织造布地膜有较好的保温性,对表层土壤的最大增温可达3.6℃,增温效果岁土壤深度的增加而减小,白天的增温效果好于晚上,环境温度高的增温效果好于环境温度低的增温效果。非织造布地膜的增温效果没有塑料地膜好,但差异不大,在农业生产中不影响使用。保湿试验证明,非织造布地膜覆盖后能减少土壤水分蒸发量,比露天少,有明显的保湿作用。保湿实验证明,非织造布地膜覆盖后能减少水分的蒸发量,在土壤基础含水率为26.7%的情况下,覆盖非织造布地膜土壤的含水量减少7.5%,比塑料地膜的5.2%略小,具有明显的保湿作用。土壤降解试验证明,秸秆纤维农业地膜在自然状态下能发生降解,土埋30天后,地膜发生降解,土埋40天后,降解率十分明显,通过扫描电镜图像可看出秸秆纤维从束状分解成多根单纤维,有大部分的纤维消失。红外光谱吸收图表明纤维大分子链发生断裂,大分子有解聚现象发生。在完全降解前,地膜会分解成散纤维状态,不会因为片状结构而造成土壤板结。因为地膜中含有废蚕丝而且稻草纤维中含有大量的钾元素,所以地膜的部分降解产物能提高土壤的氮和钾元素的含量,在非织造布地膜被土埋30天后,土壤的全氮含量增加1.0%,全钾含量增加0.17%;土埋40天后全氮量增加1.5%,全钾量增加0.22%。实验表明,天然纤维的非织造布地膜与普通塑料地膜相比,前者厚度较大,透气透湿性较好,且有较好的保温、保熵作用,但效果较后者略差。但从降解性及解决大量焚烧产生的空气污染方面,普通塑料地膜不能降解而非织造布地膜可以完全降解。但非织造布地膜的制造成本较高,影响其推广。更多还原

【Abstract】 The mulching plastic technology has obtained the rapid development in our country since we intoducted this technology from Japan from the late 1970s. At present in our country mulching plastic cover areas approximately above 14,000,000 hectares,the amount used has amounted to more than 100 ten thousand tons. It is estimated that to 2010, the national mulching plastic cover area will surpass 20,000,000 hectares. As a result of the use of majority mulching plastic for polyethylene or polyvinyl-chloride mulching plastic at present,they are not easy to degrade and hai the toxicity, the remains cannot degrade in the soil for fragment by the edaphon, and also cannot absorpted by the crops.In our country countryside, there are many straw stalk producted every year, the farmers usually deal these straw stalk with burning. But massive burning have brought the air pollution, influence environment seriously. This article mainly use the straw stalk to extraction textile fiber and use them to make nonwovens for agricultural film. Discussed the selection of raw material the ratio of the programme and the performance of field tests for the pollution-free,full-degradation film. The generalized analysis obtains the preferred plan is: The waste silk quantity is 4.02 g/m~2, square Mick is again 80 g/m~2, the bond density is 8%. The sample main performance is: The transverse failure intensity is 35N, the longitudinal breaking strength is 32N, thickness is 0.2641mm, the soak rate is 2346 g/m2h, the regain is 5.6%.Carries on the field the above mulching plastic to the cover experiment, and carries on the contrast with the ordinary plastic mulching plastic. The heat preservation experiment indicated that the natural fiber must weaves the mulching plastic to have the good heat preservation, slightly is lower than the plastic mulching plastic. Carries on the soil heat preservation performance the experiment to indicate that the natural supatex fabric mulching plastic has the good heat preservation, may reach to the surface layer soil’s biggest warming 3.6℃, the warming effect year old depth of soil increases reduces, daytime’s warming effect good in evening, ambient temperature high warming effect good in ambient temperature low warming effect. The supatex fabric mulching plastic’s warming effect does not have the plastic mulching plastic to be good, but the difference is not big, does not affect the use in the agricultural production.Moisturizer experiment proof that after supatex fabric mulching plastic cover,the film can reduce the soil moisture transpiration rate, compared to open-air few, has the obvious moisturizer function. The moisturizer experiment proved that after supatex fabric mulching plastic cover, can reduce the moisture content the transpiration rate, in the soil foundation moisture content is in 26.7% situations, the cover supatex fabric mulching plastic soil’s water content reduces 7.5%, 5.2% is slightly smaller than the plastic mulching plastic, has the obvious moisturizer function.The soil degeneration experiment proof that the straw stalk textile fiber agriculture mulching plastic can have the degeneration under the natural state, the earth buries 30 days later, the mulching plastic has the degeneration, the earth buries 40 days later, the degeneration rate is very obvious, may see the straw stalk textile fiber through the scanning electron microscope image from to tie the shape to decompose Cheng Duogen the single textile fiber, has majority textile fiber vanishing. The infrared spectrum absorption chart indicated that the textile fiber macro-molecule chain has the break, the macro-molecule has the depolymerization phenomenon occurrence. Before complete degrades, the mulching plastic can decompose disperses the textile fiber condition, will not cause the soil because of the sheet structure to harden.Because in the mulching plastic includes in the waste natural silk and the straw textile fiber includes the massive potassium element, therefore the mulching plastic part degradation product can enhance the soil the nitrogen and the potassium element content, the supatex fabric mulching plastic is buried by the earth 30 days later, the soil entire nitrogen content increases 1.1%, the entire potassium content increases 0.17%; The earth buries 40 days later the entire nitrogen quantity increases 1.3%, the entire potassium quantity increases0.22%.The experiment indicated that natural fiber’s supatex fabric mulching plastic and the ordinary plastic mulching plastic compare, the former thickness is big, the ventilation moisture-penetrability is good, and has the good heat preservation, to guarantee the entropy function, but effect the latter slightly misses. But air pollution aspect which produces from the degradability and solution massive burning down, the ordinary plastic mulching plastic cannot degrade, but the supatex fabric mulching plastic may degrade completely. But the supatex fabric mulching plastic’s production cost is high, affects its promotion.更多还原