With the method of representative investigation and site - specific observation , the effects of different vegetations on water and soil conservation in mengshan mountain were investigated on three aspects : soil melioration , entironment improvement and water and soil conservation 摘要采用典型调查和定位观测的方法，分别从改良土壤、改善环境和保特水土3方面，对蒙山不同植被下水土保持效果进行了调查。
The order of the climate production potentiality is : fugu > jiaxian > jingbian > yuyang > shenmu > hengshan > dingbian , and the order soil production potentiality is : dingbian > shenmu > fugu > hengshan > yuyang > jiaxian > jingbian . at the same time , this paper describes the guiding suggestions to improve the cropland production potentiality 提高土地生产潜力一方面要调控降水，加强基本农田建设，兴修水利，应用集流节水技术，发展灌溉农业；另一方面要改良土壤，培肥地力。
( 3 ) the key link in establishing agroforestry is to select fine plant species in accordance with local natural condition . to make full use of the coexistence and to avoid rejection between different species is very important in obtaining the utmost benefits . ( 4 ) agroforestry systems with rational structure could conserve soil and water , ameliorate soil property , raise land use efficiency and increase the system productivity and achieve significant ecological , social and economic benefits 另外在物种选择时要做到适地适树，并且要与当地主导产业结合，产生规模效益， ( 4 )良好结构的农林复合经营系统能够保持水土，改良土壤，提高土地利用率和系统生y两南农业大学硕十学位论文产力，获得更好的生态、社会和经济效益。
In this research project , the agrobacterium tumefaciens mediated transformation of badh gene of tetraploid black locust has been studied , for the purpose of improving resistance to soline - alkali and drought of tetraploid black locust ; of playing more important role in developing of waste lands , ameliorating of soline - alkali soil , and greening and beautifying of surface - mined lands , mine waste dumps , slopes of roads and railroads where restoration of vegetative cover has proven difficult ; of fully making benefits of its ability to fix atmospheric nitrogen in the soil 为了进一步提高四倍体刺槐的耐盐性和抗旱性，进一步扩大其适宜种植的生态范围，充分发挥其固氮、改良土壤的特性，在我国的城镇绿化、荒山造林、盐碱地改良以及采矿迹地、公路、铁路边坡等植物生长困难土地的植被恢复中发挥其优势，本实验对四倍体刺槐进行了农杆菌介导的甜菜碱醛脱氢酶基因转化的研究。
Abstract : based on analysis of status and structure of land resources in tengxian , it is pointed out that its limited conditions are such as less and bad land and problemes are such as unreasonable texture and no care on land use , and the suggestions and countermeasures correspondly by the idea of sustainable development such as land improving and land use control and population control have been given 文摘:在分析藤县土地资源现状的基础上，指出了不利于土地持续利用和开发的地少质差、土地利用结构不合理及重用轻养等主要问题，并根据可持续发展的思想提出了改良土壤、用途管制、控制人口等对策。
According to natural conditions of the area , natural rules and systematic engineering principle , a series of countermeasures were propased such as improving forest cover degree , enhancing water conservancy project , adjusting agricultural production constitution , combining engineering measures with ecological measures to restore mine ecosystem and to take comprehensive measures to control soil erosion so as to improve ecological environmental quality in watershed between the yangtze river and the huaihe river 针对研究区域的自然环境条件和社会经济状况，按照系统工程的原理，从遵守自然规律的角度出发提出了提高森林覆盖率，加强水利工程建设，改良土壤，因地制宜调整农业产业结构，工程措施与生物措施相结合进行矿山修复，治理水土流失，搞好生态环境保护规划，大力发展生态旅游，提高公众的环境意识，依靠科技进步促进地方经济发展的一系列改善江淮分水岭地区生态环境问题的对策。
The biological and physiological ecology characteristics of raffia grass were introduced , the relative cultivation and management techniques were summarized , and the effects of bahia grass on the soil and water conservation , the soil improvement , the environment improvement as well as the greening and beautification were expounded 摘要介绍百喜草的生物学及生理生态学特性，总结百喜草的相关栽培技术管理方法，并阐述百喜草在保持水土、改良土壤、改善环境及绿、美化等方面的作用。
