We carried out a litterbag experiment to assess the characteristics of animal manure and Tithonia diversifolia and their nutrient release dynamics in un-amended soils under different tillage systems. We conducted the study in Meru South and Kandara sub-Counties during short rains 2016 (SR16) and long rains 2017 (LR17) seasons. The treatments were; conventional tillage (ConvT) and minimum tillage (MinT). Litterbags were buried vertically in the soil to a depth of 8 cm at planting. T. diversifolia had high nitrogen concentration resulting in a significantly low C/N ratio. The recalcitrant pool (cellulose, lignin and polyphenols) was higher in animal manure compared with T. diversifolia. Nutrients (N and P) remaining from litterbags with animal manure were generally higher under MinT while in T. diversifolia they were lower under MinT in both sites. Nutrient content in both organic resources declined as the cropping season progressed. N and P release rate from animal manure was significantly higher under ConvT compared with MinT on the 8th week at Meru South site. Nutrients' release rates in T. diversifolia were significantly higher under ConvT by 57 and 48% for N and P, respectively, compared with MinT on the 6th week during SR16 season in Meru South. At Kandara site, N release rates from animal manure were significantly higher under ConvT by 60% on the 2nd week and 30% on the 8th week compared with MinT during SR16 season. The phosphorous release rate was significantly high under ConvT by 62% on the 2nd week, 43% on the 8th week and 25% on the 10th week during SR16 season. During LR17 season, N and P release rates in animal manure were significantly higher under ConvT by 54% compared with MinT on the 8th week at Kandara. Nitrogen release rates from T. diversifolia were significantly higher under ConvT by 40% on the 4th week, 30% on the 6th week and 42% on the 10th week during SR16 season. P release rate from T. diversifolia was significantly higher under ConvT by 41% on the 4th week and 32% on the 10th week compared with MinT. During LR17 season, N and P release rate from T. diversifolia was significantly higher under ConvT by 29 and 28% respectively, compared with MinT on the 8th week. Therefore, tillage, as a soil management option, influences nutrient availability from organic resources and should be considered in soil fertility management.

我们进行了一个网袋试验来评估动物粪便和特点肿柄菊，并根据不同耕作方式未修正的土壤养分释放动态。我们在2016年短雨（SR16）和2017年长雨（LR17）季节在Meru South和Kandara县进行了研究。治疗方法是：传统耕作（ConvT）和最小耕作（MinT）。种植时，将小袋垂直埋在土壤中，深度为8厘米。宽叶锥虫的氮含量高，导致C / N比明显降低。动物粪便中的顽固池（纤维素，木质素和多酚）比三角叶草高。。在MinT下，带有动物粪便的垃圾袋中残留的营养素（N和P）通常较高，而在T. diversifolia中，在两个地点的MinT下均较低。随着种植季节的进行，两种有机资源中的养分含量均下降。在Merv South站点第8周，ConvT处理下动物粪肥中的N和P释放速率明显高于MinT。在营养成分释放率T. diversifolia在Meru South的SR16季第6周，在ConvT下N和P分别显着高于MinT 57％和48％。与SR16季的MinT相比，在ConvT下，坎达拉站点的动物粪便中的氮释放率显着提高，第二周提高了60％，第八周提高了30％。在SR16季节中，在ConvT下，磷释放速率显着较高，第二周为62％，第八周为43％，第十周为25％。在LR17季节，在康达特条件下，动物粪肥中氮和磷的释放率比在坎达拉第8周的MinT要高出54％。从养分释放率T. diversifolia是ConvT下显著高出40％，在第4周，每周六日30％，并在SR16赛季第10周的42％。P释放速率T. diversifolia是显著更高ConvT下通过在第4周为41％和对薄荷相比，第10周的32％。在LR17的季节，从氮和磷的释放速度T. diversifolia ConvT下显著较高是由分别为29％和28％，薄荷8日一周相比。因此，耕作作为土壤管理的一种选择，会影响有机资源的养分利用率，因此应在土壤肥力管理中加以考虑。