Study on impact of some chemical characteristics of top soil from vegetable and orchard gardens of Amphoe Damnoen Saduak, Changwat Ratchaburi on nitrogen mineralization
1997
Siriluck Jitacksorn
This thesis has 2 parts. Part one compared management practices of gardens in 11 modern gardens of different crops, 6 vegetable and 5 orchard gardens, and a check garden, an old coconut garden having no any chemical treatment for more than 30 years on such soil chemical characteristics as total contents of logical plant nutrients. The results indicated significantly higher contents of the characteristices in the modern garden soils over the check one especially on soil P which was so high that deficiencies of cationic micronutrients might be induced that is the average total P content in the modern and that of the old one were 1,220 and 624 mg/kg, respectively. Fractionations of both soil P and soil cationic micronutrients were also investigated but negative relationship between each P fractions and that of the cationic micronutrients extracted by common methods used were not clearly observed. Part two evaluated negative effects of the excess P forms, that might induced cationic micronutrients deficiencies and that of the persisted pesticides on soil ecosystem assessed by functioning of N mineralizers by incubation studied of the 12 gardens soils having another check by modification of the original check with P and K fertilizers and liming to similar levels in the modern garden soils, and activating microbial activities in this new check with 3 levels of compost at the equivalent rates of 0, 1.5 and 3.0 tons drymass per rai. Results indicated that relative ammonium, nitrate and total nitrogen mineralization in this, new check treatment were significantly higher that of the modern gardens soil and that relative benificial activities were negatively correlated to all soil P forms except that of the Fe-P especially Al-P which is recommended for soil pollution evaluation in the aspect of organic N mineralization. Other chemical characteristics indicated no clear impacts.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by Thai National AGRIS Centre, Kasetsart University
