Study On The Comprehensive Effect Of Earthworm Breeding With Cow Dung Under Poplar Forest

Ecological technology for treating cow dung by breeding earthworms was an emerging technology in the plain formed by the flooding of the Yellow River.5 plots included bare ground?BG?,poplar woodland where earthworms had been breeding for 1 year?D₁?and the control area where was the poplar woodland without earthworms?CK₁?,poplar woodland where earthworms had been breeding for 5 years?D₅?and the control area where was the poplar woodland without earthworms?CK₅?were both used as research areas.This paper analyzed the hydrothermal condition,soil quality,poplar growth and physiological conditions of the five plots,and comprehensively evaluated the possible ecological and economic effects of the ecological technology for treating cow dung by breeding earthworms on forest land in the plain formed by the flooding of the Yellow River with a view to providing a reference for the promotion of this technology in the plain formed by the flooding of the Yellow River.The main research results were summarized as follows:?1?Earthworm breeding under the poplar forest could reduce the air temperature and the soil temperature at 0²0 cm depth at 8:00¹8:00 during the day,and increase the relative humidity of the air.The air temperature and 10 cm,15 cm,20 cm deep soil temperature were both significantly lower than the poplar woodland without earthworms?CK₁?all day in poplar woodland where earthworms had been breeding for 1 year?D₁?,and the 5cm deep soil temperature was lower than the poplar woodland without earthworms?CK₁?all day too,only the difference was not significant at 18:00 of the day.The air relative humidity was significantly higher than the poplar woodland without earthworms?CK₁?all day in poplar woodland where earthworms had been breeding for 1 year?D₁?.Earthworm breeding under the poplar forest could reduce the air temperature,air relative humidity,the 0²0 cm deep soil temperature at 8:00¹8:00 during the day.The size order of the daily range of the air temperature,relative humidity,and 0²0cm deep soil temperature was BG > CK₁ > D₁.?2?Earthworm breeding under the poplar forest could improve the physical and chemical properties of the soil,and the effect of breeding earthworms for 5 years was more significant than 1 year.The soil bulk density,p H,and organic matter were not significantly different from that of the poplar woodland without breeding earthworms?CK₁?in poplar woodland where earthworms had been breeding for 1 year?D₁?,but the soil moisture content was significantly increased by 63.15%?P<0.05?compared with poplar woodland breeding earthworms?CK₁?.The soil bulk density and p H were significantly reduced by 9.64% and 1.58%?P<005?in poplar woodland where earthworms had been breeding for 5 years?D₅?compared with poplar woodland without breeding earthworms?CK₅?,respectively.The water content and organic matter were significantly increased by 85.18% and 197.48%?P<0.05?in poplar woodland where earthworms had been breeding for 5 years?D₅?compared with poplar woodland without breeding earthworms?CK₅??P<0.05?.Breeding earthworms under the poplar forest could improve soil fertility,and the effect of breeding earthworms for 5 years was more significant than 1 year.There was no significant difference in total nitrogen,total potassium,available phosphorus and available potassium in poplar woodland where earthworms had been breeding for 1 year?D₁?compared with poplar woodland without earthworms?CK₁?,and total soil phosphorus significantly reduced by 12.31%?P<0.05?.Short-term earthworms breeding accelerated the mineralization of soil phosphorus,resulting in the loss of phosphorus without good soil structure for storage.There was no significant difference in soil total potassium in poplar woodland where earthworms had been breeding for 5 years?D₅?compared with poplar woodland without breeding earthworms?CK₅?,and the soil total nitrogen,total phosphorus,available phosphorus,and available potassium were significantly increased by 187.88%,36.54%,1257.06%,232.62%?P<0.05?respectively,compared with poplar woodland without breeding earthworms?CK₅?.The soil fertility comprehensive evaluation indicators were calculated from 7 indicators: soil bulk density,organic matter,total nitrogen,total phosphorus,total potassium,available phosphorus,and available potassium.The soil fertility comprehensive evaluation indicators in D₁,CK₁,D₅,and CK₅ plots were 0.538,0.462,1,and 0,respectively.Compared with the control areas?CK₁,CK₅?,the soil respiration carbon fluxes of the plots?D₁,D₅?for 1 and 5 years of earthworm breeding were significantly increased by 29.21% and 208.38%,respectively?P<0.05?.?3?Breeding earthworms under the poplar forest was beneficial to the growth of poplar trees,and the effect of breeding earthworms for 5 years was more significant than that for 1 year of poplar forests.The average tree height,canopy projection area,and volume of poplars in the plots breeding earthworms for 1 year?D₁?were not significantly different from the control area?CK₁?,and the breast diameter was significantly increased by 14.81%?P<0.05?.Compared with the control area?CK₅?,the average breast diameter,tree height,canopy projection area and volume of poplars in the plot?D₅?for earthworm breeding earthworm for 5 years were significantly increased by 17.14%,19.93%,32.97%,56.90%?P<0.05?.?4?The maximum net photosynthetic rates of poplar leaves in the plots where had been breeding earthworms for 2 and 6 years?D2,D6?were higher than that of the control plots?CK₂,CK₆?,that was,the maximum photosynthetic potential was greater than that of the poplar leaves in the control plots.The light compensation points of poplar leaves in the plots where had been breeding earthworms for 2 and 6 years?D2,D6?were both lower than that of the control area?CK₂,CK₆?,that was,the ability to use weak light was stronger than that of the control area.The dark respiration rates which could reflect the physiological activity of poplar leaves in the plots where had been breeding earthworms for 2 and 6 years?D2,D6?were lower than those in the control area?CK₂,CK₆?.?5?The ecological benefits included digesting feces and urine produced during livestock and poultry breeding,improving soil,and improving local water and heat conditions.Digesting feces and urine produced during livestock and poultry breeding could avoid the environmental pollution caused by its unreasonable pile,and its annual cow dung consumption was 100m3 125m3.Soil improvement could reduce local ecological and environmental problems such as soil erosion,continuous soil desertification,and soil salinization.Improving water and heat conditions could reduce the local wind and sand damage caused by the uneven distribution of water and heat conditions such as air temperature and relative humidity,soil temperature in space and time.?6?The direct economic sources of ecological technology for treating cow dung by breeding earthworms were earthworms / their dung and poplar volume.Earthworms and their dung could reach an annual net income of up to 8556 yuan per mu.If cutting down trees in summer,the plot?D₁?for breeding earthworms for 1 year could be 374.40 yuan more per mu than the control area?CK₁?,and the plot?D₅?for breeding earthworms for 5 years could have a total price of 718.93 yuan per mu more than the control area?CK₅?.The cost of using the high-temperature aerobic composting mode to produce organic fertilizer from livestock and poultry manure which had been consumed by breeding earthworms in the poplar forest was 12,000 to 26,300 yuan per mu,which was an indirect economic benefit.