Straw mulching and nitrogen application altered ammonia oxidizers communities and improved soil quality in the alkaline purple soil of southwest China

Abstract

Microbe-mediated ammonia oxidation is a key process in soil nitrogen cycle. However, the effect of maize straw mulching on the ammonia oxidizers in the alkaline purple soil remains largely unknown. A three-year positioning experiment was designed as follows: straw mulching measures as the main-plot treatment and three kinds of nitrogen application as the sub-plot treatment. We found the contents of soil organic carbon (SOC), total nitrogen (TN), available potassium (AK), available nitrogen (AN), available phosphorus (AP), and NH4+-N were increased after straw mulching and nitrogen application in alkaline purple soil, so did the amoA genes abundance of ammonia-oxidizing archaeal (AOA) and bacterial (AOB). Terminal restriction fragment length polymorphism (T-RFLP) analysis revealed that Thaumarchaeote (448-bp T-RF) was dominated the AOA communities, whereas Nitrosospira sp (111-bp T-RF) dominated the AOB communities. The community compositions of both AOA and AOB were altered by straw mulching and nitrogen application in alkaline purple soil, however, the AOB communities was more responsive than AOA communities to the straw mulching and nitrogen application. Further analysis indicated that SOC and AP were the main factors affecting the abundance and community compositions of AOA and AOB in alkaline purple soil. The present study reported that straw mulching and nitrogen strategies differently shape the soil ammonia oxidizers community structure and abundance, which should be considered when evaluating agricultural management strategies regarding their sustainability and soil quality.

The Management of Agriculture Plastic Waste in the Framework of Circular Economy. Case of the Almeria Greenhouse (Spain)

“…The estimate of the average price of plastic waste management was found through the average cost for service, including transportation (€/kg). Finally, the estimate made in Objective 2 for the cost of alternatives was made through information available in the literature (cost + dose) [68,69], the technical documents of the Reinwaste project [63,66,67] and consultation in specialized supply centers to reach the cost increase in €/ha.…”

“…Its characteristics enable it to withstand production cycles of up to nine months, which makes it an ideal replacement for mulching used throughout the crop cycle [59,65,66,69]. Other types of biodegradable mulching, such as straw or rice husks, could also be used [68,69]. Biodegradable plastic mulches have shown variable effectiveness compared to conventional polyethylene material when used in soil disinfection by the solarization technique [100,101].…”

“…On the other hand, organic mulches, such as those formed by straw, offer partially analogous benefits. Their use also leads to an increased organic carbon content [68] and the richness of the fungal community in soil [113], although they should be combined with other amendments or nitrogen compounds to avoid an excessive increase in the carbon/nitrogen ratio.…”

“…E: sanding; D: bare soil; EM: mechanical sanding. Source: own elaboration based on data provided by other authors[68,69], documents obtained from the Reinwaste project website[63,66,67] and consultations with specialized supply centers.…”