4-(4-羟基)苯乙基-1,2-二羟基苯对土壤脲酶的抑制作用

正尿素是我国农作物的主要氮肥之一,但由于土壤微生物所产生脲酶的作用,尿素施入土壤后,会迅速分解转化成氨气而造成流失,使得农作物对尿素的利用率不到40%1]。尿素无效分解,不仅降低肥效,而且过量产生氨,一方面会在各种因素的作用下转化为硝酸盐,对地下水造成污染2-3],成为环境恶化、人类患癌症的主要因素之一4];另一方面会对农作物生长造成不利影响,严重时会导致烧苗。土壤中氨含量增加,还会对正在发芽的种子产生毒性5]。

Inhibitory activity of 4-(4-hydroxyphenethyl)-1,2-dihydroxybenzene on soil urease

Leisure agriculture as a product of modern economic development has played a critical role in the development of modern agriculture. Current developments of leisure agriculture in China have been good. Despite the several methods of evaluation of leisure agriculture, this study developed a new method of evaluation of leisure agriculture in Hebei Province. This study was practically significant in promoting the development of leisure agriculture and rural tourism in Hebei Province. Leisure agriculture, a dual agriculture and tourism practice, basically characterized by marketing, science & technology, spectatorship, experience, culture, education, ecology, etc. Leisure agriculture and rural tourism demonstration sites have been typically selected by the Ministry of Agriculture and National Tourism Administration. Data Envelopment Analysis is a linear programming method for assessing the relative effectiveness of a set of conditions. It has often been used in multiple input-output scenarios. Efficiency of the input-output analysis and scale effect analysis were conducted in this study. Using a total of 12 leisure agriculture and rural tourism demonstration sites in Hebei Province for 2011, representative analyses and measures of comprehensive, economic and social benefits along with efficiency and scale benefit analyses were conducted. The results showed that overall efficiency of leisure agriculture in Hebei Province was low, and as such, needed increasing investment to attain rapid development. Six out of 12 leisure agriculture and rural tourism demonstration sites in Hebei Province was effective in comprehensive technology efficiency. As for economic or social benefits, only 2 sites were effective. Three sites were low in efficiency of investment in experience projects and tourism element type. Four sites were excessive in scientific and technological personnel. There was need to change small and fully equipped developmental patterns and to confirm scale development direction, especially for leisure experience projects. The main body of leisure agriculture management needed improving management level and service quality. According to social and economic evaluation, 1 site was deficient in employing population, and 4 sites were deficient in economic benefit. This required that based on park technology, relevant departments and main management body met not only economic benefits of improved leisure agriculture, but also increased social benefits of local employment. With government policy support (e.g., streamline management, public services, etc.), leisure agriculture development was obtainable and applicable to full market forces. This was good for mobilizing enthusiastic social forces and industrial associations for a full market research. That purpose provided decision support for building a good condition for the development of leisure agriculture in China.