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1.
全面建设小康社会的重大任务是解决"三农"问题;解决"三农"问题的重要途径是加快城镇化进程;加快城镇化进程必须走多样化的发展道路.  相似文献   

2.
贵州喀斯特山区水土流失因素与生态修复对策探讨   总被引:7,自引:0,他引:7  
张清海  林昌虎  何腾兵 《贵州科学》2006,24(3):62-65,74
贵州喀斯特山区生态环境脆弱,特殊的地质、地貌、降水等自然因素与人为因素的交叉影响使贵州喀斯特山区成为水土流失严重、生态环境恶化、人民生活贫困的地区.本文探讨了喀斯特山区水土流失因素,提出了人为因素是贵州山区水土流失的主要因素,并提出了防治水土流失与土地退化的几项工程技术措施和政策措施,对解决贵州喀斯特山区的土壤匮乏,发展农业生产,改善生态环境有一定的意义.  相似文献   

3.
贵州六盘水喀斯特山区生态环境退化已成为阻碍该区域经济发展的主要因素,而人口素质对环境的演变起着决定性作用.本研究以贵州六盘水喀斯特山区为研究对象,通过资料数据分析等方法,综合分析贵州六盘水喀斯特山区生态环境现状、人口素质现状及两者之间的关系,探寻喀斯特山区生态环境的人口压力和影响机制,发现该区域只有不断提高人口素质才能促进区域环境及经济社会的良性发展,在此基础上,寻求解决人口素质与环境之间矛盾的途径,以期减缓喀斯特山区生态环境的恶化程度,促进该六盘水经济社会和自然环境的持续发展,为有关部门提供科学参考.  相似文献   

4.
推进山区城镇化战略,是实现咸宁城乡统筹发展、城乡一体化的必由之路;是解决"三农"问题、促进新农村建设、全面建设小康咸宁的客观要求。目前正值我国实施新型城镇化推进城乡统筹的关键时期。本文对咸宁山区城镇化的现状进行了认真的调研,提出了咸宁山区城镇化的具体措施,建设性提出了相关政策、制度创新建议,具有较强的理论探索性和现实针对性。  相似文献   

5.
贵州喀斯特山区生态重建的基本模式及其环境效益   总被引:18,自引:0,他引:18  
贵州为典型的喀斯特高原山区 ,喀斯特发育的碳酸盐类岩出露面积达全省总面积的 73 %。由于自然因素和人为干扰活动的影响 ,致使生态环境严重退化 ,水土流失面积达 43 5 % ,石漠化面积达 1 33万km2 ,且每年还正以 933hm2 的速率扩展 ,已成为制约社会经济发展的主要障碍 ,恢复与重建生态环境已成了十分突出的问题和任务。文章从理论上阐述了喀斯特山区生态恢复与重建的基本措施和模式 ,并结合实例分析了它们所能产生的环境效益 ,提出了加快贵州喀斯特山区生态恢复与重建的主要对策和建议  相似文献   

6.
加快农村城镇化步伐是龙岩市经济结构战略性调整的重要任务,是解决经济社会发展诸多矛盾,特别是"三农"问题的重要途径.龙岩市的城镇化发展进程应以政府推动与市场导向型为主,多渠道推动城镇化的发展,使中等城市与小城镇共同发展,走中小城市和小城镇为主的城镇化道路,采取大力发展专业特色城镇发展模式.  相似文献   

7.
贵州喀斯特山区山多坡陡、坡耕地面积比重大,生态环境脆弱,水土流失和石漠化严重,是国家退耕还林的重点地区.本文分析了生态脆弱的贵州喀斯特退耕区发展生态农业的重要性,阐述了该地区生态农业发展的目标、任务和原则,探讨了适合喀斯特退耕区地域特征的生态农业发展的4种模式:即自给型粮食种植业、生态经济型林(果、药)业、效益型畜牧业和增值型绿色产品加工业,并提出了创新生态农业建设的投入机制、加快推进农村小城镇建设、加大生态农业建设关键技术的研究和推广力度、重点扶持生态农业建设的龙头大企业等相应的对策措施.  相似文献   

8.
喀斯特山区坡耕地水土保持型牧草筛选试验研究   总被引:3,自引:0,他引:3  
根据贵州喀斯特山区坡耕地不同立地条件对牧草的生物生态学特性及水土保持性能的要求,对搜集和引进的27份牧草的生态、社会和经济效益进行了系统研究,并采用模糊评分法对不同牧草进行了综合评分,筛选出了百喜草、皇草、紫花苜蓿、白三叶、球茎草芦、苇状羊茅、一年生黑麦草、鸭茅、百脉根等适宜于贵州喀斯特山区坡耕地种植和养畜利用的优良水土保持型牧草,为贵州喀斯特山区退耕还草、治理水土流失、发展草食畜牧业提供了科学的草种选择依据.  相似文献   

9.
“三农”问题是困扰贵州经济社会发展和现代代进程的重大障碍,是贵州建设全面小康社会必须正视的重大理论与现实课题。分析概括了贵州“三农”问题的现状及特征,并提出了解决贵州“三农”问题的对策,其核心在于“以市场化促区域特色农业建设,以非农化促农村劳动力优化配置,以城镇化促农村社会转型。”  相似文献   

10.
党的十六届五中全会提出:"建设社会主义新农村是我国现代化进程中的重大历史任务,要按照生产发展、生活宽裕、乡风文明、村容整洁、管理民主的要求,扎实稳步地加以推进."这一论断为切实解决新形势下的"三农"问题明确了奋斗目标.立足于贵州乡村的实际情况,发展乡村旅游是加快贵州新农村建设的重要途径.  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
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。  相似文献   

15.
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.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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-  相似文献   

20.
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-  相似文献   

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