Perennials are an important strategic sector for agriculture in Bulgaria. In order to obtain good results from their cultivation, a scientifically based system for the maintenance of the soil surface is needed. Existing technologies have been analyzed to support the selection of an appropriate soil maintenance system. The size of the agricultural holdings in Bulgaria for the most widespread perennial plantations, which are the vineyards and are substantiated by economically expedient technologies and machines for soil cultivation suitable for the majority of the agricultural producers, is analyzed. The advantages and disadvantages of the technologies and the machines for their realization are presented.
- AGROBIO TECHNIQUE - plant growing, animal breeding, bioenergy year VI, issue 1, 2018 http://agrobio.elmedia.net/bg/2018- 1/editorials/%D0%BA%D1%83%D0%BB%D1%82%D0%B8%D0 %B2%D0%B0%D1%82 % D0% BE% D1% 80% D0% B8-% D0% B7% D0% B0-% D0% BE% D0% B1% D1% 80% D0% B0% D0% B1% D0% BE% D1% 82 % D0% BA% D0% B0-% D0% BD% D0% B0-% D0% BF% D0% BE% D1% 87% D0% B2% D0% B0% D1% 82% D0% B0_01561.html
- NATIONAL PROGRAM FOR PEST CONTROL ON PERMANENT PLANTS DURING THE WINTER PERIOD, Sofia 2013, Annex to Order № RD 12-18 / 18.10.2013 of the Minister of Agriculture and Food http://babh.government.bg/uploads/File/Za_zem_proizvoditeli/ 13-0392-5-Prog_ovoshtni.pdf
- MAINTENANCE OF THE SOIL SURFACE IN THE WALNUT GARDEN Assoc. Dr. Eng. Kuman Kumanov http://www.fruitgrowinginstitute.com/UserFiles/HTMLEditor/ Koumanov/Koumanov_2010c.pdf
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- ИНОВАТИВНА ТЕХНОЛОГИЯ ЗА ОПАЗВАНЕ НА ЗЕМЕДЕЛСКИТЕ ЗЕМИ ОТ ДЕГРАДАЦИЯ Георги Митев Русенски университет, Русе, БългарияINTERNATIONAL SCIENTIFIC JOURNAL "MECHANIZATION IN AGRICULTURE" WEB ISSN 2534-8450; PRINT ISSN 0861-9638 https://stumejournals.com/journals/am/2015/6/3.full. pdf
- Dedousis, A., Bartzanas, Soil Engeneering, https://books.google.bg/books?hl=bg&lr=&id=AyLNvwX9hzcC&o i=fnd&pg=PA2&dq=+soil+tillage+machine+in+permanent+crops& ots=GFkJc6dnNn&sig=yylZOPc29p8jgK3J8Dyr89qTWBc&redir_ esc=y#v=onepage&q=soil%20tillage%20machine%20in%20perma nent%20crops&f=false
- Johan Arvidsson IngeHåkansson, A model for estimating crop yield losses caused by soil compaction Soil and Tillage Research Volume 20, Issues 2–4, June 1991, Pages 319-332