城市水土保持立法的必要性与重点

城镇化要坚持生态文明的理念和原则,中央要求加强生态文明制度建设,依靠制度保护生态环境.城镇化进程的加快和社会发展急需加快城市水土保持立法.城市水土保持法规应重点落实城市各功能区的政府水土保持目标责任,建立相关规划的水土保持协调机制,结合城市特点明确重点预防区和治理区,实行最严格的生产建设项目水土保持管理制度,加强城市雨洪和土石方管理,加快水土流失治理与生态修复,实行水土保持监测、公示、公报制度,建立社会监督机制,明确法律责任,增加处罚条款.     

资源型城市创新体系的培养与提升

就如何解决资源型城市转型并实现资源型城市可持续发展问题,提出了解决资源型城市现存问题的创新理论体系框架。并在生态创新、技术创新和制度创新等方面如何实施与操作进行了具体探讨,为我国资源型城市转型与发展提供了理论与实践指导。     

抓住机遇 积极探索 推动城市水土保持工作再上新台阶

自20世纪90年代我国提出和开展城市水土保持工作以来,城市水土保持工作取得了显著成效:一是拓宽了水土保持工作领域,二是建成了一批城市生态景观,三是控制了城市建设中的水土流失,四是提高了公众的水土保持意识。各地在城市水土保持工作实践中,探索和总结出了许多行之有效的好做法。当前和今后一段时期,要深刻领会搞好城市水土保持工作的重要意义,继续夯实城市水土保持工作基础,全面落实水土保持"三同时"制度,着力加快水土流失治理进度,积极创建水土保持生态文明城市,不断引入新理念、新技术、新工艺,强化宣传,努力营造城市水土保持良好氛围。对城市水土保持专委会的工作提出了要求。     

城市水土保持的新机遇新对策新措施

城市是政治、经济、文化中心,人口密度大、财富集中,在中央高度重视城镇化过程中的生态保护,社会公众对生态和生活环境质量要求愈来愈高的大环境下,开拓和发展城市水土保持工作意义重大。应加快城市水土保持立法,依靠法制促进城市生态文明建设;城市发展规划应符合生态城市的理念和要求;加快制定城市保持水土、保护生态的技术标准,规范和改进城市建设;强化城市建设项目水土保持"三同时"制度的落实,控制水土流失与生态危害;加强城市水土保持宣传教育,提高全社会的水土保持意识,共同参与城市水土保持建设。     

浅谈城市水土保持

由于我国城镇化建设速度加快,城市建设过程中不可避免地产生水土流失。本文就城市水土流失及水土保持的概念进行简要阐述,并对城市水土流失形式及其危害进行概括描述,认为城市水土流失可能引起生态失调、资源衰退、基础设施破坏和诱发地质灾害等。针对城市建设功能区划和地形等因素划分水土流失防治类型,根据不同区域、不同阶段的水土流失特点,提出了相应的水土流失防治措施,并指出建立健全城市水土保持规章,完善"三同时"制度,落实"三权",加强队伍建设,加大城市水土保持宣传和执法力度,加强经费投入和技术创新的重要性。     

天水市城市水土保持的实践与成效

天水市城市水土保持试点实践经验是强化舆论宣传,增强全民的水土保持意识是搞好城市水土保持的基础;加强领导,建立健全监督执法体系是搞好城市水土保持的基本保证;狠抓水土保持“三同时”制度的落实是搞好城市水土保持的突破口;以科技为先导,搞好城市水土保持规划,加强监测是提高城市水土保持科技含量的重要途径。统筹社会各方面的力量,建立稳定、富有生命力的多渠道、多层次、多元化的投资机制是增强城市水土保持生态环境建设活力的关键。     

城市房屋拆迁行政补偿问题研究

随着国民经济的持续快速发展和城镇化进程的加快,全国许多地区均对城市进行了大规模改造,与此同时存在的是引起了大量的房屋拆迁补偿的矛盾。本文从拆迁补偿问题入手,概述了房屋拆迁的一些基本概念以及其理论基础,详细分析了目前我国城市房屋拆迁补偿的现状,城市房屋拆迁制度的缺陷及存在的大量问题,并对其进行了思考并提出了建议。只有将这些问题通过合理的建议进行合理的解决,才能更好的建设社会主义市场经济,从而不断促进我国经济的健康发展。     

国外城镇土地利用制度及规划体系的思考

 阐述发达国家在城镇土地利用制度及规划体系方面的经验和政策措施,介绍美国、英国的城镇土地利用制度和美国、英国、德国、日本的城市土地利用规划体系,以为我国城镇化建设提供借鉴。     

重庆山地城市立体绿化发展现状问题及对策

重庆是典型的山地城市,受自然地形条件制约,城市绿化用地紧张,城市生态环境问题突出。立体绿化在不直接占用土地资源的前提下,能提高城市绿量,还能更好地契合重庆山地城市的空间特征,突出山城特色。通过对重庆市立体绿化发展现状进行调查,发现当前存在政策法规支撑不足、规划统筹不够等问题,提出了适用于重庆山地城市的立体绿化推广对策:政策支持,制度创新;摸清家底,规划引领;特色发展,树立品牌;全民参与,共建共享。     

城乡一体化进程中耕地利用变化的驱动因素及区域比较

耕地利用变化与经济发展密切相关,阐明不同经济发展阶段耕地资源变化的驱动特征,有利于缓和耕地保护与经济发展的矛盾。基于苏皖各城市社会经济发展统计数据,运用因子分析和系统聚类方法,提取影响耕地利用变化的主要驱动因子,考察其对耕地资源变化的作用机理及苏皖耕地变化驱动特征的区域差异。研究结果表明,耕地利用变化驱动力可归结为经济发展、人口与农业和制度与政策因素,经济发展带来耕地面积“N 型”变化,人口与农业因子和耕地数量之间存在高度正线性关系。城市耕地资源变化驱动类型受经济发展阶段及自身条件双重影响,工业化高级阶段城市主要受经济发展与结构调整驱动;工业化初级阶段城市人口与农业因素缓解了耕地流失;较为复杂的是工业化中级阶段城市,因经济结构、资源禀赋条件及城市功能定位等因素差异,耕地利用变化驱动力出现分异。因此各市应根据本地实际做出理性的决策,转变经济增长方式,坚持最严格的耕地保护制度,节约集约使用土地,提高土地产出效率。     

贵州草海耕地土壤与农作物中DDTs和HCHs残留及污染特征

采集草海流域周边成熟期整株农作物及土壤样品,分析测试其中DDTs和HCHs的含量,对比研究了土壤和作物中DDTs和HCHs污染水平及其在作物中富集能力。结果表明：研究区域土壤中HCHs和DDTs残留检出率均为100％,残留范围分别为0．06～16．66μg·kg^-1和0．08-39．77μg·kg^-1,土壤中HCHs和DDTs的残留量均小于国家土壤环境质量一级标准;三种农作物中DDTs、HCHs及∑（DDTs,HCHs）残留量差异显著,HCHs含量最高的是玉米,DDTs和（DDTs,HCHs）最高的是马铃薯;三种农作物中HCHs和DDTs残留的风险系数均为1．1,属于低度风险,农作物中DDTs、HCHs及∑（DDTs,HCHs）的安全指数IFSc均小于1,DDTs和HCHs残留量对三种农作物安全影响的风险是可以接受的。     

陇陕片预警减灾工作的成效与做法

自 1991年长江上游水土保持重点防治区滑坡、泥石流预警系统运作以来 ,陇南陕南片成功预报和处理滑坡、泥石流险情 10 3处 ,保护人口 11 6 8万 ,避免经济和财产损失 11879 6 5万元 ,取得了良好的社会效益。主要做法及经验是 :依靠各级政府 ,健全预警网络 ;广泛深入宣传 ,增强防灾意识 ;健全管理制度 ,落实岗位职责 ;强化技术培训 ,提高业务技能 ;加强检查指导 ,现场解决问题 ;及时调查险情 ,做好技术服务 ;预防治理结合 ,注重减灾实效。     

Changes in yield and gas exchange parameters in Festulolium and alfalfa grown in pure sowing and in mixture under drought stress

Crop performance and yield are the results of genotypic expression as modulated by continuous interaction with the environment. Among environmental factors, water is globally one of the most limiting for crop production. Water resources in the world are steadily diminishing and in many areas, including Poland, more frequent periods of drought are being observed. The aim of the study was to compare the yields and gas exchange parameters of Festulolium hybrid (Festulolium braunii (K. Richt) A. Camus) and alfalfa (Medicago?×?varia T. Martyn) under different levels of soil moisture (well-watered conditions and drought stress) and cultivation method (pure stand and mixture). The study has shown that all the measured parameters were affected by drought stress. Net photosynthetic rate, transpiration rate, stomatal conductance and dry mass yield were significantly lower under drought stress than under well-watered conditions in all treatment types. Alfalfa grown in a pure sowing showed the strongest reaction to stress, while hybrid Festulolium grown in mixture showed the weakest. It was also found that under stress, grass assimilated CO₂ and evaporated water much more intensively in mixture cultivation than in pure sowing. Higher water use efficiency (WUE) was observed in alfalfa and Festulolium growing in mixture only in the first year of the study.     

Cadmium Effects in Sunflower: Membrane Permeability and Changes in Catalase and Peroxidase Activity in Leaves and Calluses

Mechanisms preventing oxidative burst in cells exposed to high metal concentrations are crucial for cell survival. In this report, sunflower (Helianthus annuus L.) was used as a model species to investigate: (a) how cadmium (Cd) affects plant defense pathways (in particular, those involved in preventing oxidative stress), and (b) whether antioxidative enzymes of plants and of in vitro cell culture (calluses) have similar responses to Cd exposure. For this experiment, plants (grown hydroponically on Long Ashton medium) and calluses (grown on Murashige and Skoog medium) were exposed for three weeks to different Cd concentrations (0, 5, 50, and 500 μ M). Solute and electrolyte leakage increased significantly with the increase in Cd concentration in the external medium and in exposed leaves, and less in exposed calluses. Cadmium exposure also reduced significantly soluble protein contents in both leaves and calluses. The activities of catalase and peroxidase decreased significantly in 50 and 500 μ M-exposed leaves compared with the control, but increased in 5 μ M-exposed calluses, decreasing in the calluses exposed 500 μ M Cd. The decrease in antioxidative enzymes activities is congruent with the decrease in membrane integrity and suggests that calluses develop antioxidant mechanisms that respond better to Cd stress than do leaves. On average, 100% of plants exposed for 21 d to 500 μ M and 95% of plants exposed for 45 d to 50 μ M Cd were dead. After 45 d, only 53% of 50 μ M-exposed calluses had died. These surviving calluses were maintained on 50 μ M for six months. Six-month-old exposed calluses had higher activities of peroxidase and catalase when compared with control calluses, as well as lower membrane degradation. These data show that calluses are more tolerant than plants to Cd exposure, and that antioxidant mechanisms under Cd exposure may differ between the two cell systems and vary with time.     

肯尼亚和中国农业资源投入与农业单产水平变化

当前,肯尼亚和中国在生产足够粮食以保障粮食安全方面都面临着严峻的挑战。尤其是对于肯尼亚而言,因为其2100年预测的人口将达到2018年的1.4倍,且其粮食生产在过去并没有大幅度的改善。而中国近些年粮食生产能力显著提高。本文系统分析了肯尼亚和中国农业资源投入、种植业和畜牧业单产水平的历史变化,以及农业资源投入与产量之间的关系,为肯尼亚粮食危机和消灭贫困提供更多的理论支撑。研究结果表明,在20世纪60年代,肯尼亚耕地、草地和降水等自然资源人均占有量比中国高2~3倍,且人均食物能量和蛋白质供应显著高于中国。当前,肯尼亚人均资源拥有量仍高出中国约30%,但是其人均食品供应和粮食自给率却远低于中国平均水平。这是由于与肯尼亚相比,中国在种植业和畜牧业长期持续的投入,大幅度地增加了种植业和畜牧业能量或蛋白质单产水平。1961-2017年,中国和肯尼亚作物蛋白的平均单产分别增加282%和44%。中国的数据表明,种植业和畜牧业单产水平与肥料、精饲料、机械和农药的投入具有显著正相关性;农牧业生产结构对单产水平的变化影响也很大,如种植业中蔬菜和水果播种面积占比,畜牧业中单胃动物饲养占比等。总的来说,农业资源投入和农业结构对生产力的提高都有很大的影响,这可能是肯尼亚提高农业生产力的潜在选择。     

Fungal abundance and diversity in earthworm casts and in uningested soil

Earthworm casts and adjacent uningested soil from 30 different locations were compared to determine the abundance and diversity of fungal species. The casts contained larger fungal populations (g^-1 dry soil weight) and numbers of fungal species than the soil. Variations in these parameters between casts and soil were statistically significant (P=0.05). Fungal populations and the number of fungal species in casts and soil also varied significantly (P=0.05) between samples from different locations. A total of 27 fungal species were recorded from the casts and soil. Indices of dominance (0.084 casts; 0.14 soil) and general diversity (2.53 casts; 2.02 soil) demonstrated that the casts displayed more diverse fungal flora than the soil. The diversity of fungal species increased in earthworm casts after passing through the earthworm gut.     

云南省开展水土保持的做法与成效

云南省各级党政领导重视和支持水土保持 ,积极出台有关法规、政策 ,为搞好水土保持工作提供了保障。治理中坚持高起点要求 ,有力地推动了水保产业化建设。适应市场经济要求 ,大力发展水土保持专业户、重点户 ,调动社会各方面力量参与水土流失治理开发。介绍了具体的做法、成效及今后做好水保工作的思路。     

1,4-Dimethoxyglucobrassicin in Barbarea and 4-hydroxyglucobrassicin in Arabidopsis and Brassica

A novel indole glucosinolate, 1,4-dimethoxyglucobrassicin (1,4-dimethoxyindol-3-ylmethylglucosinolate), was isolated as the desulfo derivative from roots of the P-type of Barbarea vulgaris ssp. arcuata, and its structure was determined by spectroscopy including 2D NMR spectroscopy. 4-Hydroxyglucobrassicin (4-hydroxyindol-3-ylmethylglucosinolate) was isolated as the desulfo derivative from green siliques (fruits) of Arabidopsis thaliana and identified by comparison of its (1)H NMR spectrum with the spectrum of the known desulfoglucosinolate from Brassica napus. The delayed elution of desulfo indole glucosinolates from the DEAE Sephadex column used in sample preparation was examined, and the diode-array UV spectra of desulfo indole glucosinolates were measured, to ensure a reliable determination of 1,4-dimethoxyglucobrassicin and 4-hydroxyglucobrassicin with the existing analysis method based on the HPLC of desulfoglucosinolates. 1,4-Dimethoxyglucobrassicin was not detected in 10 other Arabidopsis, Brassica, and Barbarea species, indicating an evolutionarily recent mutation in the indole glucosinolate biosynthesis in B. vulgaris ssp. arcuata type P.     

Aorta and liver changes in rats fed cholesterol-containing and raw vegetable-supplemented diets: experiments in vitro and in vivo

The aim of this investigation was to compare the liver and aorta changes in rats fed cholesterol-containing diets and the possible improvement when diets would be supplemented with frequently used raw vegetables. The phenolic compounds of three vegetables in methanol-water (1:1) fraction were characterized using electrospray ionization mass spectra (ESI-MS). Results showed that the content of polyphenols, flavonoids, quercetin, flavanols, tannins, and ascorbic acid varied for garlic and white and red onions ranging from 6.68 to 18.08 mg GAE/g DW, 490.4-701.0 μg CE/g DW, 281.2-1100.0 μg, 32.40-41.30 μg CE/g DW, 2.88-3.12 mg CE/g DW, 1.87-2.33 mg AA/g DW, 1388.2-1442.3 μg CGE/g DW, respectively. The radical scavenging capacities (μM TE/g DW) for the same investigated vegetables for ABTS, FRAP, CUPRAC, and DPPH assays ranged from 48.78 to 92.42, 9.41-28.56, 3.06-10.41, and 6.49-23.42, respectively. Good correlations were observed between the phenolic contents and the radical scavenging capacities of the vegetables. The interaction between BSA and quercetin, BSA and garlic and onions extracts was measured by 3-dimensional fluorescence (3D-FL) and Fourier transform infrared (FT-IR) spectroscopy. The highest polyphenol content was found in methanol/water fraction of onions and garlic; therefore, for the investigation of in vitro interactions with BSA only polyphenols of this fraction were used. For in vivo studies, 30 male Wistar rats were divided into 5 groups each of 6 and named Control, Chol, Chol/Garlic, Chol/OnionRed, and Chol/OnionWhite. During 6 weeks, the rats of all 5 groups were fed a basal diet (BD). The rats of the Control group were fed the BD only. The BD of the Chol group was supplemented with 10 g/kg of nonoxidized cholesterol (NOC). Each of the other three groups was supplemented with 10 g/kg of NOC and 500 mg of raw fresh garlic, 500 mg of raw fresh red onion, and 500 mg of raw fresh white onion on 1 kg of body weight for Chol/Garlic, Chol/OnionRed, and Chol/OnionWhite diet groups, respectively. In order to detect the changes in the liver and aorta, a histological procedure was applied, and the liver enzymes were determined and compared. It was found that the main changes vs the Control group were in the liver of rats fed the cholesterol-containing diet without vegetable supplementation. Significantly less histological changes in the liver and lower level of liver enzymes vs those of the Chol group were detected in rats of the Chol/Garlic group (P < 0.05). The interaction between the polyphenol extract of garlic and BSA in vitro showed its strong ability comparable with that of quercetin to quench the intrinsic fluorescence of BSA. In conclusion, all studied vegetables showed protective effects, but raw garlic supplemented with cholesterol-containing diets significantly prevented the aorta and liver damages of rats.