Utilisation of waste wool from mountain sheep as fertiliser in winter wheat cultivation

ABSTRACT

Coarse wool obtained from mountain sheep has low economic value and is treated as a troublesome by-product of sheep farming. To find ways to utilize it, waste separated from the better-quality wool during sheep shearing was used as a fertilizer in winter wheat cultivation. During the preliminary tests, it was stated that unwashed wool does not contain excessive amounts of heavy metals and environmentally unfriendly contaminations and can be safely used as a fertilizer. Then, the raw wool was cut into shorter segments and mixed with the soil, and its influence on winter wheat growth during two seasons was examined. Simultaneously, the progress of wool biodegradation and the nitrogen content in the soil were analyzed. It was stated that, during vegetation, nitrogen compounds are slowly released into the ground, and the content of nitrogen in the soil is strictly correlated with the progress of wool biodegradation. Released nitrogen positively impacts wheat growth in various stages, which is manifested by higher tillering degree, more intense leaf color, higher stems and finally, greater yield. Wool added into the soil reveals its positive influence on wheat development up to two harvests. Mountain sheep wool can be successfully used as a nitrogen-rich, organic fertilizer in organic farming. This enables utilization of coarse wool, which is not suitable for textile processing, according to the zero-waste strategy.

摘要

从山羊身上获得的粗羊毛经济价值较低，是养羊业的一种麻烦的副产品. 为了找到利用它的方法，在剪羊毛过程中从质量更好的羊毛中分离出来的废物被用作冬小麦种植的肥料. 在初步测试中，有人指出，未清洗的羊毛不含过量的重金属和对环境不友好的污染物，可以安全地用作肥料. 然后，将生羊毛切成较短的段并与土壤混合，研究其对两个季节的冬小麦生长的影响. 同时分析了羊毛的生物降解过程和土壤中的氮含量. 研究表明，在植被生长过程中，氮化合物缓慢释放到地面，土壤中的氮含量与羊毛生物降解的进展密切相关. 释放的氮对小麦各阶段的生长有积极影响，表现为分蘖度越高，叶色越浓，茎干越高，最终产量越高. 添加到土壤中的羊毛对小麦生长发育有积极影响，最多可收获两次. 山羊毛可以成功地用作有机农业中富含氮的有机肥料. 根据零浪费战略，这使得不适合纺织品加工的粗羊毛得以利用.

KEYWORDS:

• Sheep
• wool
• waste
• nitrogen
• fertilizer
• wheat

关键词:

• 羊
• 羊毛
• 浪费
• 氮
• 肥料
• 小麦

Acknowledgements

This research was funded by a Norway Grant titled “Polish sheep wool for improved resource utilisation and value creation.” NOR/POLNOR/WOOLUME/0007/2019.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Highlights

• The wool obtained from Polish mountain sheep does not contain any excess heavy metals and can be safely applied as a clean soil additive.

• During vegetation season, the compact wool’s keratin structure is gradually broken down, while nitrogen-rich compounds are gradually released into the soil.

• The slowly released compounds ensure nitrogen supply in different stages of winter wheat growth.

• At harvest, the remnants of wool still contain a significant amount of nitrogen, which supports re-growth of wheat in the second vegetation season.

Additional information

Funding

The work was supported by the EEA Grants/Norway Grants [NOR/POLNOR/WOOLUME/0007/2019].