Yang G.,Huazhong Agricultural University |
Yang G.,MOA Key Laboratory of Crop Ecophysiology |
Zhou X.,Huazhong Agricultural University |
Li C.,Huazhong Agricultural University |
And 3 more authors.
Industrial Crops and Products
Either canola (Brassica napus L.) or cotton (Gossypium hirsutum L.) production in China ranks the first in the world in planting area and/or output. Three quarters of Chinese canola are grown in Yangtze River Valley and half of cotton planting area is cropped with canola sequentially. Cotton stubble are normally removed from the field or burned in situ before canola sowing to facilitate field management, and potentially to reduce the incidence of diseases. However, the way of cotton stubble disposal is labor costing, resources wasting and/or air pollution contributing. Hence, two-growing-season field experiments were conducted to evaluate the effect of cotton stubble mulch with stalk remaining straight and lying down at elongation stage on canola grain yield, canopy temperature and soil nutrients status. The first experimental treatments were established following a split-plot design of a randomized complete block with cotton stubble mulching (0 and 3250kgha-1) as the main plot and canola planting density (22.5, 30.0, and 37.5plantsm-2) as the sub-plot. The results revealed that canola yield under cotton stubble mulching (CSM, 3250kgha-1) was 9.9% higher than that under no cotton stubble mulching (NCM, 0kgha-1) averaged across two growing seasons, possibly because canola canopy mean daily temperature (MDT) of CSM was 0.5°C higher than NCM during the winter. Planting density significantly affected canola yield as well, where moderate planting density (30.0plantsm-2) resulted the highest canola yield (2425kgha-1). The second experiment was designed to compare soil nutrient content between CSM and NCM, which revealed that soil nutrition, especially alkaline N and available K, was improved by cotton stubble mulching. The results suggest that cotton stubble mulching would be a multi-win alternative choice for cotton stubble disposal and 30.0plantsm-2 should be the optimal density for canola production in the region. © 2013 Elsevier B.V. Source
Zhang Z.S.,MOA Key Laboratory of Crop Ecophysiology |
Zhang Z.S.,Huazhong Agricultural University |
Cao C.G.,MOA Key Laboratory of Crop Ecophysiology |
Cao C.G.,Huazhong Agricultural University |
And 4 more authors.
Journal of Soil Science and Plant Nutrition
We conducted a 3-year feld experiment on an Anthrosol paddy soil to investigate changes in crop yield, P uptake and soil organic phosphorus (P) fractions after 3 years of conventional tillage (CT) conversion to no-tillage (NT) under a rape - rice rotation in central China. Treatments were established following a split-plot design of a randomized complete block with tillage practice as the main plot and fertilizer as the sub-plot treatment. The yields of rape and rice ranged from 1378 to 2264 kg ha-1 and from 5895 to 9453 kg ha-1 across 3 years, respectively. Moreover, P uptake for rape and rice (aboveground) varied from 3.9 to 10.4 kg ha-1 and from 9.5 to 32.0 kg ha-1, respectively. Fertilization significantly enhanced crop yields and P uptake, but tillage did not affect the yields and P uptake. Fertilization significantly increased total P concentrations, acid phosphatase activity, Bray-1 P and labile organic P in the 0-5 cm soil layer. Compared to the CT treatments, the NT treatments had significantly higher acid phosphatase activity, total P, Bray-1 P, total organic P and organic P fractions in the 0-5 cm soil layer but lower organic P fractions in the 5-20 cm soil layer. Therefore, our results suggest that short-term NT does not enhance organic P concentrations in the 0-20 cm soil layer, and only improve P availability on the soil surface. Source
Li C.,MOA Key Laboratory of Crop Ecophysiology |
Li C.,Huazhong Agricultural University |
Zhang Z.,MOA Key Laboratory of Crop Ecophysiology |
Zhang Z.,Huazhong Agricultural University |
And 6 more authors.
A two-year field experiment was conducted to investigate the effects of different tillage (no-tillage [NT] and conventional tillage [CT]) and seeding methods (transplanting seedlings [TPS] and throwing of seedlings [ST]) on methane (CH4) and carbon dioxide (CO2) emissions from double rice cropping systems in central China. The CH4 and CO2 fluxes for early rice ranged from-2.52mgm-2h-1 to 125.0mgm-2h-1 and from 99.3mgm-2h-1 to 1463.6mgm-2h-1, respectively, whereas the fluxes for late rice varied from-7.22mgm-2h-1 to 242.3mgm-2h-1 and from 180.6mgm-2h-1 to 2219.0mgm-2h-1, respectively. Compared with NT, CT significantly increased (P<0.05) the CH4 and CO2 emissions, where the seasonal total CH4 emissions from the CT treatment were 1.75-2.10 times of those from the NT treatment for early rice and 1.64-1.79 times for late rice. Moreover, compared with the CT treatment, the NT treatment significantly reduced seasonal total CO2 emissions by 19%-33% for early rice (P<0.05) and by 27%-31% for late rice (P<0.05). The seeding methods significantly affected CH4 and CO2 emissions. Compared with TPS, ST significantly decreased seasonal total CH4 and CO2 emissions by 15%-40% (P<0.05) and 19%-33% (P<0.05) for early rice, and by 38%-47% (P<0.05) and 19%-22% (P<0.05) for late rice, respectively. These results may be attributed to reduced root growth and aboveground biomass. Therefore, simplified cultivation technologies are effective for reducing carbon emissions from double rice cropping systems in central China, and the combination of NT with ST can more effectively decrease carbon emissions. © 2013. Source