The Lerma River Upper Basin is located between Almoloya del Rio shallow lakes and Atlacomulco Municipality in the State of Mexico;is a natural resource essential to human activities in its surroundings and serves as a...The Lerma River Upper Basin is located between Almoloya del Rio shallow lakes and Atlacomulco Municipality in the State of Mexico;is a natural resource essential to human activities in its surroundings and serves as a source of electricity and drinking water for Mexico City. However, this river is threatened by over-exploitation of its aquifers, disappearance of many of its wellsprings and uncontrolled discharges of wastewater from all sorts. Thus, the aim of this work was to evaluate the water quality in the Upper Lerma River Basin using WQI proposed by the NSF and compare these results with those obtained by the National Water Commission of Mexico (CNA). WQI was calculated using seven parameters: dissolved oxygen, pH, DOB5, temperature change, total phosphates, nitrates, and total solids obtained in four different sampling campaigns carried out in 2005, 2006 and 2012. The results showed that water quality in the Upper Lerma River is bad, mainly associated with high levels of BOD5, nitrates and phosphates found. The results obtained with WQI yielded the same diagnosis that the studies carried out by the CNA, in which water quality was unacceptable. It is worth noting that there is a significant water quality deterioration in the Upper Lerma River Basin with the course of the years, because in 2012 were observed the lower index values regarding 2005 and 2006, so it is imperative to implement measures to restore and preserve the water quality of this important river.展开更多
In order to provide a more suitable environment for tobacco leaf growth, this study collected meteorological information and tobacco leaf quality information from the main tobacco-producing counties in the province an...In order to provide a more suitable environment for tobacco leaf growth, this study collected meteorological information and tobacco leaf quality information from the main tobacco-producing counties in the province and conducted relevant analysis to find out the main meteorological factors affecting the growth, development, yield, and quality of upper tobacco leaves. Clarify the suitable climatic conditions for the growth and development of the upper leaves, and clarify the influence of various meteorological factors on the quality of the upper leaves. The results showed that the nicotine and total nitrogen content of the upper leaves were significantly positively correlated with the average daily temperature during the maturity period, and negatively correlated with the rainfall during the maturity period;the rainfall in July was significantly positively correlated with the upper leaf clutter score, which was sufficient in the mature period. Moisture conditions are conducive to alleviating the upper leaf clutter;the number of sunshine hours in August is the main factor affecting the content of aroma substances in the upper leaves, and it is also significantly positively correlated with the content of aroma substances.展开更多
In order to improve the curing quality and industrial availability of upper tobacco leaves,the effects of different temperature differences between dry and wet bulbs in yellowing stage on the chemical composition,arom...In order to improve the curing quality and industrial availability of upper tobacco leaves,the effects of different temperature differences between dry and wet bulbs in yellowing stage on the chemical composition,aroma substances and economic characters of upper tobacco leaves were investigated using field test and indoor test. The results showed that when the dry bulb temperature was 38℃ and the temperature difference between dry and wet bulbs was 1. 5℃,the coordination of chemical constituents and the content of aroma substances in the upper tobacco leaves were increased,the appearance quality and sensory evaluation quality were significantly improved,and the economic characters after curing were improved,thereby improving the yield and quality of the upper tobacco leaves.展开更多
文摘The Lerma River Upper Basin is located between Almoloya del Rio shallow lakes and Atlacomulco Municipality in the State of Mexico;is a natural resource essential to human activities in its surroundings and serves as a source of electricity and drinking water for Mexico City. However, this river is threatened by over-exploitation of its aquifers, disappearance of many of its wellsprings and uncontrolled discharges of wastewater from all sorts. Thus, the aim of this work was to evaluate the water quality in the Upper Lerma River Basin using WQI proposed by the NSF and compare these results with those obtained by the National Water Commission of Mexico (CNA). WQI was calculated using seven parameters: dissolved oxygen, pH, DOB5, temperature change, total phosphates, nitrates, and total solids obtained in four different sampling campaigns carried out in 2005, 2006 and 2012. The results showed that water quality in the Upper Lerma River is bad, mainly associated with high levels of BOD5, nitrates and phosphates found. The results obtained with WQI yielded the same diagnosis that the studies carried out by the CNA, in which water quality was unacceptable. It is worth noting that there is a significant water quality deterioration in the Upper Lerma River Basin with the course of the years, because in 2012 were observed the lower index values regarding 2005 and 2006, so it is imperative to implement measures to restore and preserve the water quality of this important river.
文摘In order to provide a more suitable environment for tobacco leaf growth, this study collected meteorological information and tobacco leaf quality information from the main tobacco-producing counties in the province and conducted relevant analysis to find out the main meteorological factors affecting the growth, development, yield, and quality of upper tobacco leaves. Clarify the suitable climatic conditions for the growth and development of the upper leaves, and clarify the influence of various meteorological factors on the quality of the upper leaves. The results showed that the nicotine and total nitrogen content of the upper leaves were significantly positively correlated with the average daily temperature during the maturity period, and negatively correlated with the rainfall during the maturity period;the rainfall in July was significantly positively correlated with the upper leaf clutter score, which was sufficient in the mature period. Moisture conditions are conducive to alleviating the upper leaf clutter;the number of sunshine hours in August is the main factor affecting the content of aroma substances in the upper leaves, and it is also significantly positively correlated with the content of aroma substances.
文摘In order to improve the curing quality and industrial availability of upper tobacco leaves,the effects of different temperature differences between dry and wet bulbs in yellowing stage on the chemical composition,aroma substances and economic characters of upper tobacco leaves were investigated using field test and indoor test. The results showed that when the dry bulb temperature was 38℃ and the temperature difference between dry and wet bulbs was 1. 5℃,the coordination of chemical constituents and the content of aroma substances in the upper tobacco leaves were increased,the appearance quality and sensory evaluation quality were significantly improved,and the economic characters after curing were improved,thereby improving the yield and quality of the upper tobacco leaves.
