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1.
随着朝阳市铁矿采选业快速发展,乱挖、乱采、废渣随意排放,对环境破坏日益严重,在分析问题产生的基础上提出整治措施。  相似文献   

2.
亚高山草甸类草地退化评估及草地保护对策   总被引:1,自引:0,他引:1  
为研究亚高山草甸类草地退化及草地保护对策,在实地测定大量样方和统计分析的基础上,选取了盖度、物种多样性指数、丰富度指数、物种数、草地质量指数、优良牧草比例等指标作为评估指标,制定了亚高山草甸类草地生态质量评估的4级指标值。选择各级别典型生态区域,对其现状和指标值进行了对比分析。结果表明,该方法反映了植被生态的量化指标,各项指标相互联系和相关,具有易获得性和实用性,符合当地生态质量现状,可以科学、客观地评估区域生态质量。超载过牧,滥采乱挖,人为破坏,生物链失衡等是造成生态退化的人为因素。控制放牧,防止滥采乱挖,建立自然生态保护区是维护该区域生态系统平衡的措施。  相似文献   

3.
欧洲城市水土保持考察及其思考   总被引:6,自引:1,他引:6  
在考察欧洲城市水土保持的基础上,介绍了欧洲有关国家在修建公路、城市化开发的生态建设、矿区生态恢复、维护河流生态平衡、城市背景的生态风景林以及水源保护林等方面的经验,提出了提高我国水土生态建设水平的措施,包括:体制上实行城乡一体化,城乡土地实行统一管理,杜绝乱开发现象;城乡建设要维护大地景观格局的连续性,保证水土生态资源的永续利用;营建生态法治文明。  相似文献   

4.
《中国水土保持》2011,(8):38-38
<正>为了抓好水土保持重点治理项目区管护工作,该局与乡村两级签订了《水土保持重点治理项目区管护公约》,该公约明确规定:禁止在保护区内进行乱砍、乱开、乱烧、乱挖等破坏植被人为造成水土流失的一切行为  相似文献   

5.
书库清点和开架借阅的管理中最为常见的问题都是乱架,分析了书库图书乱架的根源,提出了一条从书库排架方式疏导乱架的新思路。  相似文献   

6.
《中华人民共和国水土保持法》(以下简称《水保法》)经七届人大常委会第20次会议审议通过,已正式颁布。这是我国水土保持工作的一件大事。《水保法》的公布施行,标誌着我国水土保持工作走上了法制轨道。我国疆域辽阔,山区和丘陵区约占国土面积的2/3。在这类地区,由于长期以来土地利用不合理,乱垦、乱牧、滥伐,地面植被遭到破坏,因而都存在着程度不同的水土流失。  相似文献   

7.
南方水田少(免)耕法研究报告   总被引:14,自引:0,他引:14       下载免费PDF全文
三年来,在黄粘土、砂壤土实行少(免)耕法栽培水稻,均有普遍的增产趋势.少(免)耕不翻乱土层,保持了土体的原状稳态结构,增强了抗逆外来的不良环境,稳定和协调了土壤肥力,这对促进水稻早发,稳长具有重要意义.水田渍水耖耙是造成土壤结构破坏、粘闭,影响根系活力和作物产量的主要原因.因此水田必要的耕作应尽可能采取干耕干耙,以不翻乱土层为原则,同时必须以种植制度为主体,采取不同耕法的有机配合,以建立良性生态循环、用养结合、低耗高效的土壤耕作新体系.  相似文献   

8.
根据当前农村存在的“脏、乱、差”环境问题,紧紧围绕全面建设小康社会的总体目标,为建设“清洁水源、清洁家园、清洁田园”的社会主义新农村,提出了切合实际的对策与建议。  相似文献   

9.
1983—1985年漳州市开展了水土流失的普查工作。通过普查,证实了全市的水土流失是严重的,危害是巨大的,损失是惊人的。引起水土流失的自然因素主要有降水量多而强度大,暴雨极值达160.3—273.7毫米,加上山高坡陡,地形起伏,红土不长草;人为因素有破坏植被,保水保土措施不当,乱垦乱种,耕作粗放,不合理的改变地形地貌。防治对策包括有目的、有计划、有科学的治理水土流失;建立防护体系时,要突出生物措施,加强科学研究工作。  相似文献   

10.
明清之际黄河洪水泛滥 ,朝廷对黄河上中游地区林木保护给予了关注 ,地方政府颁布告示 ,明晰林权 ,解决民间纠纷。光绪年间刻立的《积石峡关护林碑》 ,在当时起到了约束山民、禁止乱伐和保护水土的作用 ,对今天开展黄河上中游的水土保持有积极的启迪作用。  相似文献   

11.
不同水氮管理对菠菜生长和水氮利用的影响   总被引:7,自引:4,他引:7  
针对传统水肥方式中存在的投入过量问题 ,采用控制耕层土壤湿度以及应用KNS氮素推荐系统对菠菜的产量及水氮利用进行了研究。结果表明 ,推荐施氮处理与传统施氮处理对菠菜的生长没有明显的差异 ,而控制耕层土壤水分含量为植物有效的土壤含水量的 50%~80%及 60%~90%时的处理产量比传统灌水处理有显著性增加。推荐灌水施氮模式同传统灌水施氮模式相比 ,菠菜产量没有明显的差异 ,但是氮素以及水分供应量分别减少了 73.6 %和 39.2% ,相应地水分利用效率提高 64% ,氮素利用效率也有显著提高。推荐的水氮处理在菠菜收获后土壤无机氮残留量比传统处理明显降低。因此在合理灌溉的基础上进行氮素推荐 ,可有效地解决蔬菜生产中产量与环境之间的矛盾  相似文献   

12.
我国滑坡、崩塌的区域特征、成因分析及其防御   总被引:2,自引:0,他引:2  
论述了我国滑坡、崩塌的区域分布特征,滑坡和崩塌的危害程度,滑坡和崩塌类型和成因分析,并且提出了灾害的防御措施,以期达到环境保护成为社会发展过程中的一个重要组成部分。  相似文献   

13.
采用液质联用仪比较分析了3个不同种植区域(江苏南京、广西南宁和湖南长沙)露地和大棚两种种植条件下黄瓜和土壤中甲基硫菌灵及其代谢物多菌灵的残留动态,同时对黄瓜中的最终残留量进行了比较分析。施药后,甲基硫菌灵在黄瓜和土壤中均能很快转化为多菌灵[施药后1 d甲基硫菌灵未检出(〈0.01 mg·kg-1)],多菌灵在露地黄瓜和土壤中的原始沉积量均低于大棚。3个试验点露地黄瓜中的半衰期分别为2.3、1.4 d和1.4 d,在大棚黄瓜中的半衰期分别为2.6、1.7 d和2.0 d。在3个试验点露地土壤中的半衰期分别为1.6、1.7 d和2.3 d,在大棚土壤中的半衰期分别为2.3、2.0 d和2.3 d。最终残留试验在最后一次施药后1 d采样时,大棚、露地黄瓜中的甲基硫菌灵均未检出(〈0.01 mg·kg-1),多菌灵在3个试验点露地黄瓜中的最终残留量为0.014~0.162 mg·kg-1,而在3个试验点大棚黄瓜中的最终残留量为0.121~0.561 mg·kg-1。参照我国所制定的黄瓜中多菌灵的MRL(0.5 mg·kg-1),露地种植方式下所有处理黄瓜中甲基硫菌灵代谢物多菌灵的最终残留量均符合国家标准的规定,但大棚种植方式下其残留量有超标的风险。  相似文献   

14.
简析了婺源县城镇开发区建设过程中造成水土流失的状况、危害、原因后,提出了其防治措施,并阐明开展城市(镇)水土保持的紧迫性。  相似文献   

15.
Soils were collected from 2-year (2-y) and 3-year (3-y) old red-pine seedling plots in two tree nurseries, Hayward in the north and Wilson in the southwestern part of Wisconsin State respectively, and equilibrated with 0.01 M Ca(NO3)2 for soil solution Zn and Mn (solu-Zn and Mn), and with 0.01 M Ca(NO3)2+0.005 M EDTA for soil adsorbed Zn and Mn (ad-Zn and Mn). Buffering capacity of soil Zn and Mn (b-Zn and Mn) was obtained from the ratio of ad-Zn and Mn to the solu-Zn and Mn. The concerned traces in pine seedling needles (ndls), stems(sts) and roots (rts) were simultaneously measured.  相似文献   

16.
Abstract

Lucerne (Medicago sativa L.) and phalaris (Phalaris aquatica L.) were grown separately and together in a pot trial on a yellow‐brown pumice soil with three rates of sodium (Na) and two rates of potassium (K) in factorial combination. Lucerne alone had a low Na concentration but growing phalaris as a companion grass produced herbage with a Na concentration adequate for stock. Na application increased the Na concentration in phalaris and the mixture of phalaris and lucerne much more than in lucerne alone; had little effect on K concentration; slightly reduced Mg concentration; and greatly reduced Ca concentration but not as much in lucerne as in phalaris or the mixture with lucerne. K application increased K concentration and reduced Na, Ca and Mg concentrations throughout. Yield of phalaris grown alone and in combination with lucerne was increased significantly by Na application when K concentration in the plants was low. Yield of lucerne was not affected by Na application and it is concluded that Na did not substitute for K in this species. It is concluded that field trials are warranted to investigate the possibility of growing a special purpose mixture of lucerne and phalaris on New Zealand yellow‐brown pumice soils to provide feed that has adequate Na for grazing animals.  相似文献   

17.
20世纪末,开发建设项目水土保持方案的编报工作已经实现了规范化和制度化,但有不少的编制者在编制建设类和建设生产类项目的水土保持方案时往往出现失误.建设类和建设生产类项目的水土保持方案在很多方面都存在很大区别.根据多年编制两类水土保持方案的实践经验,总结出了这两类项目水土保持方案的编报工作在水土保持要求、服务年限、预测时段划分、防治目标等方面的异同,以防止在编报过程中出现水土流失量预测、水土保持措施体系以及水土保持监测等方面产生较大的偏差.  相似文献   

18.
Cocoa and chocolate products from major brands were analyzed blind for total antioxidant capacity (AOC) (lipophilic and hydrophilic ORAC(FL)), catechins, and procyanidins (monomer through polymers). Accuracy of analyses was ascertained by comparing analyses on a NIST standard reference chocolate with NIST certified values. Procyanidin (PC) content was related to the nonfat cocoa solid (NFCS) content. The natural cocoa powders (average 87% of NFCS) contained the highest levels of AOC (826 +/- 103 micromol of TE/g) and PCs (40.8 +/- 8.3 mg/g). Alkalized cocoa (Dutched powders, average 80% NFCS) contained lower AOC (402 +/- 6 micromol of TE /g) and PCs (8.9 +/- 2.7 mg/g). Unsweetened chocolates or chocolate liquor (50% NFCS) contained 496 +/- 40 micromol of TE /g of AOC and 22.3 +/- 2.9 mg/g of PCs. Milk chocolates, which contain the least amount of NFCS (7.1%), had the lowest concentrations of AOC (80 +/- 10 micromol of TE /g) and PCs (2.7 +/- 0.5 mg/g). One serving of cocoa (5 g) or chocolate (15 or 40 g, depending upon the type of chocolate) provides 2000-9100 micromol of TE of AOC and 45-517 mg of PCs, amounts that exceed the amount in a serving of the majority of foods consumed in America. The monomers through trimers, which are thought to be directly bioavailable, contributed 30% of the total PCs in chocolates. Hydrophilic antioxidant capacity contributed >90% of AOC in all products. The correlation coefficient between AOC and PCs in chocolates was 0.92, suggesting that PCs are the dominant antioxidants in cocoa and chocolates. These results indicate that NFCS is correlated with AOC and PC in cocoa and chocolate products. Alkalizing dramatically decreased both the procyanidin content and antioxidant capacity, although not to the same extent.  相似文献   

19.
During the 5th International Conference on Polyphenols and Health that was held in Sitges (Spain) in October 2011, the latest advances in this area of active research were presented. Sessions on polyphenol effects on cardiovascular disease, polyphenols as ingredients of functional foods, the role of polyphenols in preventing obesity and diabetes, the interaction of polyphenols with gut microbiota, bioavailability and metabolism of polyphenols in humans, the mechanisms of action of these metabolites in different models, new methodologies for the study of the role of polyphenols in health, polyphenols and cancer, recent developments in phenolic compounds and neuroscience, and polyphenols in epidemiology and public health were organized. This highlight issue presents a selection of papers from invited speakers, oral presentations, and poster prize winners. The perspectives for this exciting area of very active research were also discussed at the meeting and are summarized in this introductory paper.  相似文献   

20.
果蔬在贮运过程中的生物力学特性及质地检测   总被引:14,自引:4,他引:10  
为了研究果蔬贮运过程中的品质变化,从力学的角度,讨论了果蔬组织结构与生物力学性质间的关系,分析了果蔬机械损伤特点,介绍了目前果蔬质地力学检测的应用情况和技术概况,总结了该技术目前存在的问题,提出了今后研究的方向和建议。  相似文献   

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