陇西县退耕还林成果总结及后续产业发展思考

1、退耕还林成果 1．1 工程规模 自2000年以来,陇西县完成退耕还林工程41．11万亩,其中退耕地还林14．96万亩,还草0．1万亩,配套荒山造林工程24．45万亩,封山育林1．6万亩。工程涉及全县17个乡镇,200个行政村,1200个社,受益农户32000户、16．2万人。     

甘肃省新一轮退耕还林实施现状及存在的问题

甘肃省前一轮退耕还林从1999年率先在全国开始试点,截至2006年底全省完成退耕地造林66.89万hm2。为确保"十一五"期间全国耕地不少于1.125亿hm2,2007年国家对退耕还林政策作了调整,2007年~2013年暂停退耕地还林计划任务安排,要求各省摸清耕地底数后,在重点生态脆弱区和重要生态区位继续实施退耕还林还草,重点治理25°以上坡耕地。2014年新一轮退耕还林重新启动。作者参与全省退耕还林检查验收经历10余年、2015年参与完成了全省新一轮退耕还林质量督察、2017年3月参与完成了"甘肃省林业厅退耕还林突出问题专项整治督察",作者通过多年工作实践提出新一轮退耕还林实施现状及存在的问题。     

黄土高原退耕还林(草)区的鼠害治理问题

综述了黄土高原退耕还林(草)过程中鼠害问题及防治现状.退耕(牧)还林(草)对黄土高原地区的生态建设与可持续发展意义重大,鼠害始终是困扰黄土高原植被建设的重要问题,截至2004年底,西部12个省(区)的鼠害实际发生面积已达264.3×104hm2,地处黄土高原的陕西、甘肃、宁夏、青海、山西、内蒙古为最严重的省(区);环境变化、人类活动的压力、鼠类的天敌减少以及退耕还林(草)中缺少科学观念,仓促实施是鼠害发生的主要原因;鼠害对植被建设、经济发展、生态环境以及公共卫生安全影响巨大,但在治理方法上尚没有取得突破性的进展;本文对黄土高原鼠害治理现状和存在问题进行了分析,提出建议:(1)退耕还林(草)在总体规划中应纳入包括鼠害防治在内的林、草管护措施;(2)加大防治资金投入;(3)加强科学研究;(4)健全预测预报体系.     

退耕还林还草工程实施后的生态经济系统良性循环分析

按照"退耕还林(草),封山绿化,以粮代赈,个体承包"的基本方针,以生态经济学和生态恢复学的基本原理为依据,总结了五年来我国退耕还林还草工程的完成情况,论述了退耕还林还草、恢复林草植被对改善生态环境,发展国民经济,促进农民增收,走向小康社会的重大意义,分析了西部地区经济系统演变规律,对退耕还林还草工程实施后生态环境良性循环的动态进行了初步探讨.     

基于退耕还林还草的科尔沁沙地土地利用变化研究——以库伦旗芒汗苏木为例

退耕还林还草是我国在西部地区实施的一项重大生态环境建设工程．选取内蒙古退耕还林还草重点区域——科尔沁沙地为研究区,以沙地典型区3期遥感数据为本底,研究其近5年的土地利用变化,结果发现,经过5年的退耕还林还草工程,研究区耕地减少,林地和草地的数量、质量明显增加和提高,沙地面积大范围缩小;研究区现以草地为主,镶嵌有林地和耕地,沙地呈条带状集中分布在南部边缘,退耕还林还草工程初见成效。     

张掖市退耕还林建设工程的成效分析

退耕还林是以政府行为对自然资源的栽培过程。退耕还林还草工程是我国为改善西部地区恶化的生态环境而采取的一项重大的生态建设工程。退耕还林还草工程不仅改善了生态环境,而且对农民生活、区域经济发展、后续产业建设也产生了巨大的影响。根据对张掖市退耕还林工程实施情况的核查资料,分析了实施退耕还林还草工程后取得的成效、带动后续产业发展、促进农民增收、加快地方经济发展的途径和重要作用。     

宁南山区生态建设中退耕还林还草深层次问题的思考

通过分析研究宁南山区实施退耕还林还草的制约因素，提出退耕还林还草必须与解决群众的长期生活问题同步进行，与改善农业生产条件和提高农业生产效益同步考虑，必须创造良好的外部环境，减少退耕还林还草的中间摩擦，使退耕还林还草和坚持生态优先真正得到落实，彻底防止边治理边破坏的问题．     

试论退耕还林草工程建设

退耕还林草是牵涉到亿万农民切身利益的大事，是政策性极强的工程，是联系党心、民心的德政工程。认真总结、探索、研究和推广退耕还林草工程的经验，分析和解决退耕还林草工程实施过程中出现的问题，对退耕还林草工程建设的持续稳定发展是至关重要的。本文通过对榆阳区十三个乡镇退耕还林草工程的调查研究、总结，分析退耕还林草实施中的作法和存在的问题，并就实施退耕还林草工程建设提出建议。     

基于GeoMap的天祝退耕还林还草项目评价信息系统研究

针对甘肃天祝县退耕还林还草项目管理的实践，在VB环境下利用GeoMap开发了退耕还林还草项目的评价信息系统。设计了退耕还林还草项目评价信息系统的主要功能和数据库结构。并在此基础上，探讨了空间数据库组织、空间数据库与属性数据库之间的连接、可视化表达等系统开发中的关键技术，研究表明利用CeoMap可以实现退耕还林草项目评价信息系统的基本功能。     

基于GIS的济南市山丘区退耕还林还草决策分析

利用遥感和GIS技术，分析了济南市山丘区退耕还林还草的耕地数量及空间分布情况。通过对TM遥感影像的目视解译获得最新的土地利用数据，然后从土地利用数据中提取出旱地；利用地理信息系统的图层叠加功能，分析不同坡度、不同土壤侵蚀强度和不同土壤侵蚀危险度条件下的旱地面积及分布；结合研究区具体情况，制定退耕还林还草原则，最后提出济南市退耕还林还草方案。本研究可以为济南市的生态环境建设规划提供科学的决策依据。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that