Study On Soil Enzyme Activity And Physico-chemical Properties Of Shelterbelt In Regimental Farm 150 Of Shihezi

All biochemical processes and material circulation are run through the catalytic action of the soil enzyme in soil ecosystem. Soil physico-chemical properties can reflect the situation of soil moisture, air, heat, fertility. It is one important property of soil fertility. So, study on soil enzyme activity and soil physico-chemical properties are very significant, especially in studing soil fertility and improving soil conditions. The soil enzyme activity and physico-chemical properties of shelterbelts were analyzed in Regimental Farm 150 of Shihezi. The features of soil enzyme activity and physico-chemical properties of main shelterbelts were revealed in this region. The results showed as follows:(1) Among different layers of the same section, there is no obvious rule except the polyphenol oxidase in vertical distribution. The soil surface had the largest activity of the remaining 5 enzyme Meanwhile, the soil enzyme activity decreased with the increased depth of the soil layers. However, with varying degrees of diminishing.(2) In addition to the catalase, soil enzyme activity of the 4 year-old shelterbelts are less than other ages'shelterbelts. Overall, soil urease activity, soil invertase activity and soil alkaline phosphatase activity were increased with the increased ages of shelterbelts. The order of soil protease activity is as follows:28a>10a>12a>4a. The order of soil catalase activity is as follows: 12a>4a>28a>10a, and the order of soil polyphenol oxidase activity is as follows:10a>28a>12a>4a.(3) Different species have different enzyme activity of shelterbelt. Overall, Albag inaceae had higher soil enzyme activity of 4 year-old shelterbelts without soil invertase activity. Hamamelis virginiana also had high soil enzyme activity of 4 year-old shelterbelts. Furthermore, mixed forests of the same shelter forest had higher enzyme activity than pure forest. P.euphratica. xElacagnus is a good example. Without the activity of polyphenol oxidase,P.euphratica. xElacagnus had higher enzyme activity than their pure forest.. (4) Loam soil is the smajor soil type of the study area,which accout for 81.82%,and only 18.18% is clay. Overall, the soil fertility levels is poor in Regimental Farm 150 of Shihezi. The specific performance is as follows:Low organic matter content, lack of phosphorus, nitrogen and available Mn. Meanwhile rich in potassium and available Fe,Cu,Zn. At the same soil profile, the soil bulk density increased with the increased depth. The soil bulk density of one species is higher than mixed forests. The improvement soil physical properties is obvious by 4 year-old P.euphratica. xElacagnus.(5) The soil enzyme activity and physico-chemical properties of shelterbelt had close relationship.Soil bulk density and pH value have significant negative correlation with soil enzyme activity. Soil moisture, total nitrogen. organic matter, nitrogen.and soil enzyme activity have significant positive correlation with soil enzyme activity. The content of available Fe and available Zn have closed relation with soil enzyme activity. Overall, soil enzyme activity had positive correlation with soil nutrients. Multiple stepwise regression analysis showed that:Variety of enzyme activity had very close relationship with soil moisture, soil bulk density, alkali-hydro nitrogen, total phosphorus, organic matter, rapidly-available potassium and pH. Soil physico-chemical properties and soil available trace elements had very close relationship with the activity of soil urease, soil catalase, soil invertase, soil protease, soil alkaline phosphatase and soil polyphenol oxidase Therefore, we can use soil enzyme activity as evaluation index of soil fertility.