Numerical model to assess the impact of the strategies to mitigate desertification

Desertification is considered a global environmental problem with political and socioeconomic implications. Desertification, exacerbated by climate change, is the largest environmental problem in Chile affecting almost two third of the national territory. This study takes place in a latitudinal gradient of the north-central Chilean drylands, where desertification is a threat to agriculture, livestock and forestry (ALF). In the context of the United Nations Convention to Combat Desertification (UNCCD) and the implementation of the Chilean National Action Programme (NAP), the country is conducting policies and investing in mitigation strategies to combat land degradation and desertification. The main objective of this paper is the development of an integrative methodological approach using real data of the territorial and socioeconomic indicators. With the proposed methodology we assess the impact of the mitigation and land degradation strategies supported by the ALF promotion agencies in the fight against desertification, projecting different scenarios of change. The data were collected in 2008 in Santiago, Chile. The results of the Principal Component Analysis (PCA) suggest that technical irrigation and the improvement of grasslands and pastures play an important role in the fight against desertification. The results of the model projections are consistent, suggesting that the efforts of the ALF promotion agencies have a positive impact in fighting desertification. Inaction of ALF mitigation strategies would increase desertification. This methodological approach, performed with real data, is a contribution for the development of integrative assessments, for replication and for forthcoming discussions.     

城镇生活污水就近引灌沙漠造林

城镇生活污水排入水体，严重影响水资源的使用价值。沙漠地区因缺水，造成许多地方造林失败。本文提出了城镇生活污水就近引灌沙漠造林的构想，从经济和环境影响两个方面将其与传统方案进行了比较，结果表明，新方案优势明显。     

以学定教,提高课堂教学效率

根据心理学理论,学习是一个学生内化的过程,学生是自主学会的,而不是被动教会的。因此在教学中,教师只有做到以学定教,才能有效提高教学效率,促进学生对知识的掌握。     

求木之长先固本 欲流之远须浚源——环境科技支撑为更好环境管理服务的思考

回顾了云南省40年的环境科技工作,分析了存在的不足,提出了为环境管理提供支撑的改进措施。     

群文阅读提升学生阅读能力的适切性探究

文化体制改革,增强学生阅读能力的教学要求日益凸显,也成为课堂教学的一大难题,通过教师教学方式的不断探索,群文阅读的教学思路初具雏形。群文阅读是在增加学生阅读数量的同时,注重学生阅读质量的提高。阐释了群文阅读如何在语文课堂合理实施,旨在通过群文阅读教学达到阅读能力的提高,提升学生语文学习的综合素养。     

如何推动地方落实13万个建制村的环境综合整治任务

随着我国财税体制改革步伐的不断加快,农村环境"以奖促治"政策的实施范围、推进方式、资金管理等发生了深刻变化,同时,一些地方农村环境综合整治又存在政府积极性不高、责任难以落实、环境成效较差的问题,如何推动地方落实《水污染防治行动计划》提出的,到2020年完成13万个建制村的环境综合整治任务,是现阶段我国农村环境综合整治面临的新形势。本文在准确把握当前农村环境综合整治形势下,提出了今后一个时期推进我国农村环境综合整治的工作思路,分别从严格目标考核、引入激励机制、建立长效机制和重视各方参与4个方面,提出了约束与激励相结合的农村环境保护措施,以期为新时期深化"以奖促治"政策、推进农村环境综合整治提供参考和借鉴。     

番禺:蓝天碧水迎"南拓"

广州南拓，番禺得福。 作为广州南拓区域，番禺将是广州市21世纪的重点发展地区，珠江三角洲乃至华南地区的新兴产业和区域服务业核心区、航运中心和临港产业区，同时将建设成为经济繁荣、社会进步、环境优美、交通便捷、城乡协调发展、具南国水乡风情特色的现代化新区。[编者按]     

关注全球气候变化,提高抵御气候灾害的能力

我国是个受全球季风气候影响较大的国家。受全球气候变暖的影响,云南梅里雪山的明永冰川已发生后退现象,西双版纳也已出现一些变化的前兆。为维护生态安全,云南省应统筹好人与自然和谐相处的关系,防止人为决策失误造成的区域性生态系统结构的破坏,同时要加强有关气候变化对云南影响的预警研究。     

倾听灵魂的吟唱——浅析梁志玲的散文创作

梁志玲对于散文创作有着执著的追求,其散文创作整体上包孕着强烈的生命意蕴;读她的散文,常常能感悟到一种饱满的生命感,体悟到生命的本真和价值意义。梁志玲的散文,立足家乡小城壶城崇左,关注身边现实俗世,从自己的体验出发,抒发时代变化情感,营造独特生命意蕴。其散文作品温情浓郁但又多少有点委婉哀伤,具备了非同一般的精神追求,闪露出独特的个体诗性魅力。梁志玲的散文可谓一曲又一曲的灵魂之吟唱,可以直接切入读者心灵深处。     

“英”山有路巧激趣 学海无涯“效”作舟

爱因斯坦说过,兴趣是最好的老师。要想提高学生的英语成绩,教师要培养学生学习英语的兴趣,让学生能够主动学习,并且要关注学习的过程,构建有效的课堂。     

水利工程环境影响研究若干问题探讨

本文简述当代水资源利用和水利工程环境影响研究的发展趋势,总结我国在水利工程环境影响研究上的进步,成绩和不足。着重提出加强水利工程环境影响研究和评价的六点建议:①强调价值观在环境影响评价中的指导作用;②深化和拓宽移民环境容量研究;③加强环境影响的经济评价研究;④开展水利工程环境影响的风险分析;⑤充实环境对策体系研究;⑥积极建立长期定位观测台站。     

南水北调中线工程对生态环境的影响及其对策

本文研究了“南水北调”中线工程实施之后,对被调水的汉江中下游及其它有关区域的生态环境所产生的影响,该工程实施之后,有可能使汉江中下游水位降低;加剧汉江中下游农业用水差值和缺水状况;可能使汉江中下游水质变劣,向北方调送污水;使汉江中下游淤积程度加重,治理投资加大,气候有所变异。据此,本文提出实施该调水工程时,应同步修建沙市-沙洋的“两沙运河”,加强对汉江中下游段水环境的综合整治两项对策,以最大限度地减少和消除该调水工程实施之后对生态环境的不利影响。     

Changes in groundwater levels and the response of natural vegetation to transfer of water to the lower reaches of the Tarim River

Restoration and reconstruction of the degraded Tarim River ecosystem is an important challenge.A goal of an ecological water conveyance project is to protect and restore the natural vegetation in the lower reaches of Tarim River by transferring water from Bosten Lake,through the river channel,to the lower reaches.This study describes the changes in groundwater depth during the water transfer and the respondence of riparian vegetation to alterations in groundwater levels.The results indicate that groundwater depth along the Tarim River channel has a significant spatial-temporal component.Groundwater levels closest to the river channel show the most immediate and pronounced changes as a response to water transfer while those further away respond more slowly,although the observed change appears to be longer in duration.With a rise in the groundwater level,natural vegetation responded with higher growth rates,biomass and biodiversity.These favorable changes show that it is feasible to protect and restore the degraded natural vegetation by raising the groundwater depth.Plant communities are likely to reflect the hysteresis phenomenon,requiring higher water levels to initiate and stimulate desired growth than what may be needed to maintain the plant community.Because different species have different ecologies,including different root depths and densities and water needs,their response to increasing water availability will be spatially and temporally heterogenous.The response of vegetation is also influenced by microtopography and watering style.This paper discusses strategies for the protection and restoration of the degraded vegetation in the lower reaches of the Tarim River and provides information to complement ongoing theoretical research into ecological restoration in arid or semi-arid ecosystems.