关键词: 施氮量,  , 秸秆还田,  , 晚播小麦,  , 养分平衡

Abstract: We analyzed the canonical correlation between environmental quality monitoring indicators of Guangxi and statistical indicators of yearbook such as nature, economy, population, energy, pollutant emissions at three time scales of 5 years (from 2011 to 2015), 10 years (from 2006 to 2015) and 15 years (from 2001 to 2015) by canonical correlation analysis (CCA). Results showed that: (1) The canonical correlation between factor’s environmental quality and nature, economy, population and energy of Guangxi had an upward trend with the increases of time scales. The correlation was statistically significant at the time scales of 10 and 15 years. However, establishing the canonical correlation at the time scale of 5 years needed a close increase in the time of quarterly samples. (2) The major loading of atmospheric environmental quality was charged by the comprehensive pollution index of air quality, sulfur dioxide, fine particulate matter (PM_2.5), and nitrogen dioxide. The major loading of water quality was charged by the comprehensive pollution index of water quality, COD_Mn, ammonia, DO, and Cd. The major loading of ecological environment was charged by ecological index, vegetation coverage index, and water network density index. The major loading of key pollutant sources monitoring indices was charged by the number of enterprises that discharge waste water, waste gas and municipal wastewater treatment plants, and standard discharge rate of sewage treatment. (3) Air quality indices including integrated pollution index of air quality, SO₂, PM_2.5, NO₂ as well as frequency of acid rain had positive correlation with water quality indices including integrated pollution index of water quality, COD_Mn, Cd, DO, ammonia, petroleum, and total phosphorus, while the pH of acid rain had negative correlation with these indices of air and water quality. The number of pollutant sources enterprises had positive correlation with the concentrations of main atmospheric and water quality indices. (4) Nature, economy, population, energy, and pollutant emissions were the driving forces for the changes of comprehensive environmental quality of Guangxi. The adjustment of environmental quality monitoring evaluation indicators had profound impacts on the dynamics of environmental quality. Our results provide reference to regional economic development, land use optimization, energy utilization, environmental protection, and environmental quality evaluation.

Key words: nitrogen application rate, straw returning, late sowing winter wheat, nutrient balance.