Effects Of Mulching And Maize Intercropping Pasture On Soil Temperature, Respiration And Plants Production

The shortage of precipitation resources, underground water pollution and soil desertification were key factors, which constrain agriculture and husbandry sustainable production in the Shiyang River Basin in Gausu Province. To improve irrigation water use efficiency and land productivity and to find the suitable maize intercropping pattern and mulching materials, an experiment was conducted at the Huangyang Town, Wuwei City, Gansu Province, Gansu Agricultural University Experiment Station from March to October in 2014. The experiment followed a completely randomized split-plot design, taking intercropping patterns(maize monoculture, maize//hairy vetch intercropping and maize//common vetch intercropping) as main plot treatment and mulching methods(common plastic film mulching, biodegradable film mulching, straw mulching and no-mulching) as split-plot treatment. And effects of intercropping patterns and mulching methods on soil temperature, soil moisture, soil respiration, maize photosynthetic characteristics, legume nutritional value, crop yields and water use efficiency(WUE) were studied in the experiment. The results showed as following.Soil temperature increased for common plastic film mulching and biodegradable film mulching, but decreased for straw mulching. Compared with no mulching, topsoil(0-25 cm) temperature increased 1.1 and 0.7℃, respectively, for the common plastic film mulching and biodegradable film mulching, but decreased 0.6℃ for straw mulching. Soil water storage in the 120 cm depth increased 23, 18 and 8 mm, respectively, for common plastic film mulching, biodegradable film mulching and straw mulching. Maize Intercropping pasture increased soil water content, but decreased topsoil temperature. Compared with maize monoculture, topsoil temperature decreased 0.4 and 1.0℃, respectively, for maize intercropping pea and maize intercropping common vetch, while soil water storage in the 120 cm depth increased 9 and 16 mm.Soil respiration and rhizosphere microbes increased for the common plastic film mulching and biodegradable film mulching, but soil respiration decreased and rhizosphere microbes increased for straw mulching. Compared with no mulching, soil respiration increased 12.2% and 5.6%, respectively, for common plastic film mulching and biodegradable film mulching, but decreased 1.2% for straw mulching. Rhizosphere microbes increased 15.2%、73.3% and 132%, respectively, for common plastic film mulching, biodegradable film mulching and straw filming. Compared with maize monoculture, soil respiration increased 35% and 25%, respectively, for maize intercropping pea and maize intercropping common vetch, while rhizosphere microbes increased 38% and 85%.Compared with no mulching, photosynthetic rate increased 17%, 14% and 4%, respectively, for common plastic film mulching, biodegradable film mulching and straw filming, while solar energy utilization increased 7%, 6% and3%. Compared with maize monoculture, soil respiration increased 3%, respectively, for maize intercropping pea and maize intercropping common vetch, while changes of solar energy utilization were not distinct..Compared with no mulching, system hay yields increased 8%, 7% and 3%, respectively, for common plastic film mulching, biodegradable film mulching and straw filming, while legumes crude protein yields increased 4%, 6% and 9%. Compared with maize monoculture, system hay yields increased 6% and 7%, respectively, for maize intercropping pea and maize intercropping common vetch, while crude protein yields increased 701 and 472 kg ha-1.Compared with no mulching, system grain yields increased 10.0%, 6.9% and 4.2%, respectively, for common plastic film mulching, biodegradable film mulching and straw filming, while system WUE increased 16.5%, 9.9% and 8.7%. Compared with maize monoculture, system grain yields increased 2.0% and 1.4%, respectively, for maize intercropping pea and maize intercropping common vetch, while system WUE increased 4.8% and 7.6%.Considering for grain yields, hay yields and soil water content, common plastic film was the suitable mulching material. But considering for ecology and sustainable development, biodegradable film was the suitable mulching material. Maize intercropping legume, especial maize intercropping common vetch, increased irrigation water use efficiency and land productivity.