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利用耐盐植物改善盐土区农业环境 总被引:19,自引:0,他引:19
耐盐植物具有特定的抗盐性,有泌盐、稀盐、拒盐、耐盐等多种多样对盐渍生境的适应方式。全球盐生植物约有1560多种,中国有502种。许多耐盐植物有重要的经济价值。可以广泛用于食品、纺织、酿造、建筑、医药、化工等方面。更重要的是其对改良土壤、调节气候、维护生态平衡的环境效茄。种植耐盐植物增加地面覆盖,减少土壤蒸发,吸收带走土壤中的盐分。从而减少耕作层盐分累积。同时增加土壤有机质,改善土壤理化性状,促进对盐土有效改良和利用;还町以降低噪音、净化空气、减少温差、增加雨量、减少地表风蚀和十热风危害。通过引进、驯化、筛选、辐射诱变、多倍体育种等手段,我国已经选育出经济价值高、有应用价值的耐盐植物150种。本文简要介绍了这些耐盐植物对盐土的改良效果和经济利用价值。 相似文献
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为了摸清盐生植物在南北疆改良盐碱地的实际应用效果,更好地利用盐碱植物,在南北疆地区进行田间试验,研究了两种盐生植物在新疆南北疆盐碱地的适应性及吸盐能力。结果表明,盐生植物在南疆的成活率明显高于北疆;而盐地碱蓬成活率明显要高于海篷子;北疆种植的盐生植物其植物体内的总含盐量明显高于南疆种植的盐生植物,其中盐地碱蓬高出约55%,海篷子高出约46%。由此可以看出,盐地碱蓬和海篷子更适合于南疆地区生长,而在北疆环境两种盐生植物吸盐能力均强于南疆环境,海蓬子吸盐能力明显强于盐地碱蓬。 相似文献
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对滨海盐碱地土壤和植物样品分析结果表明,生长不同盐生植物的土壤含盐量不同,以生长白刺(Nitraria sibirica Pall.)的土壤含盐量最高,达18.5 g/kg,盐地碱蓬(Suaeda salsa L.Pall.)次之,柽柳的最低。盐生植物的生长改变了土壤养分特征,4种生长盐生植物的土壤养分含量均高于光板地,土壤有机质含量增加44%以上,生长木本盐生植物白刺、柽柳(Tamarix chinensis Lour.)的土壤养分含量高于生长草本盐生植物碱蓬、碱茅(Puccinellia distans Jacq.Parl.)的土壤,且不同盐生植物养分特征不同,白刺、柽柳N和P含量均高于盐地碱蓬、碱茅,K含量则与植物耐盐特性有关。 相似文献
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为探讨施用脱硫废弃物对生长在盐土和碱土上的不同植物耐盐特性的影响,并建立综合评价指标体系,对不同植物的耐盐指数进行综合评价。本试验在2008—2010年期间,分别在碱土区和盐土区2个试点,以施与不施脱硫废弃物为主处理,选用9种不同耐盐植物为副处理开展了田间裂区试验,观测分析了各耐盐植物的出苗特征、生长生理特征、产量等指标及土壤盐分、养分、碱化度(ESP)等性质,从而建立包括植物生长、生理指标、土壤指标和经济指标的综合评价指标体系,并应用TOPSIS法对不同耐盐植物的耐盐指数进行综合评价。结果表明:与CK相比,施用脱硫废弃物能显著改善各耐盐植物的生长发育,提高出苗率、相对生长速率(株高)和相对生物量,增加自由水和束缚水的比值(F/B),且在碱土上效果优于盐土。不同类型耐盐植物之间差异显著,表现出各自的耐盐、碱特性。同时施用脱硫废弃物种植耐盐植物可提高土壤有机质增加速率和全盐、碱化度的降低速率。同样地,对盐碱土的改良效果表现为碱土优于盐土,不同耐盐植物之间差异显著。通过综合评价把不同耐盐植物分为强、较强、中和弱4个耐盐等级。与CK相比,施用脱硫废弃物可提高耐盐植物的耐盐等级,扩展耐盐植物在盐碱地上的种植范围。由此可知,耐盐植物的耐盐特性受植物类型、盐碱地类型、改良措施等因素影响。因此,从生态经济的角度寻求合理的综合评价方法来确定耐盐植物的耐盐特性具有重要科学意义,可为进一步优化盐碱地生态修复模式提供理论支持。 相似文献
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根据野外实际调查和文献查阅,初步收集了新疆盐生植物共305种15变种7亚种,隶属38科124属,分别占新疆种子植物区系科、属、种的38.0%、17.3%和8.9%,约占中国盐生植物总数的60%。其中约35%的种未被《中国盐生植物》收录,约1/2的种未被“世界盐生植物数据库”收录。盐生植物中约63.9%的种集中分布于藜科、菊科、禾本科和豆科中,多数建群植物为中亚、亚洲中部或地中海地区盐生植物区系成分,盐生植被的旱生特性明显。 相似文献
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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
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安阳市近10年来建成的水土保持工程的主要建设管理方式可分为3种,即:乡村组织治理,完成后分配给农户分散经营;乡村组织治理,由村成立专业队代表村集体管理;把小流域或荒山承包给个体或私人经济组织,由其自行治理和经营管护。3种建管方式中以后者为最优,其经济效益是分散经营管理的5倍、专业队经营管理的3.5倍。针对水保工程建设管理中存在的问题和适应农村税费改革等要求,提出了加快安阳市水保生态建设的建议。 相似文献
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Much evidence has indicated that the occurrence of montmorillonite and vermiculite containing Al-interlayers is very common in solis, particularly acid soils. Viewed in the light of soil clay minerology, it would be required to investigate the properties of their original minerals. For the latter purpose, the Al-interlayer has been removed prior to the Mg-glycerol,K-saturation and heating tests for identification of montmorillonite and vermiculite. Its removal has been accomplished in sevsral ways; KOH plus KCl (1), NH4F, KCl plus HCl (2), Na-citrate (3),400C de hydroxylation-NaOH (4) dissolution. Although these methods are effective for the removal of Al-interlayers, they seem drastically to affect the minerals or are time-consuming. Inthe course of the study of hydroxy-Al interlaid complexes of expanding 2:1 layer lattice clay minerals, the authors have noticed the difference between the (001) spacings of hydroxy-Al complexes of montmorillonite and vermiculite; the former exhibited the 20 A basal spacing at room temperature against the 14 A spacing of the latter. This difference might be useful for differentiating montnmorillonite-chlorite intergrades in soils. 相似文献
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为探讨硒、钴在提高苜蓿生长影响,在河南省沿黄滩区,开展了硒、钴单施和配施下对紫花苜蓿生长以及产量和品质影响研究。结果表明,硒、钴单施和配合基施均能够显著提高苜蓿从现蕾到开花期的净光合能力,降低呼吸消耗,提高单位叶面积干物质的生产速率,有利于苜蓿花前青干草生产和果实发育;其中,以硒570 g/hm2、钴762g/hm2配施下效果显著,青干草增产8.06%,种子千粒重可提高12.85%。单施钴和硒钴配施还能促进0—20 cm耕层苜蓿根瘤菌的生长和积累,增强苜蓿的固氮能力。说明硒钴合理基施对苜蓿青干草和优质种子生产具有很好的应用效果。 相似文献
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Separation and analysis of diastereomers and enantiomers of cypermethrin and cyfluthrin by gas chromatography 总被引:5,自引:0,他引:5
Synthetic pyrethroid (SP) insecticides are of environmental significance because of their high aquatic toxicity. Due to their chirality, SP compounds contain multiple diastereomers and enantiomers. However, due to great structural similarities and lack of isomer standards, gas chromatographic (GC) analysis of SP diastereomers or enantiomers is poorly developed. In this study, we used a HP-5 column to separate the diastereomers and a beta-cyclodextrin-based enantioselective column (BGB-172) to separate the enantiomers of cypermethrin (CP) and cyfluthrin (CF). Resolved peaks were identified by comparing chromatograms of isomer-enriched CP products. Diastereomers of both CP and CF were separated on the HP-5 column. On the BGB-172 column, enantiomers of all cis diastereomers were separated, while those of trans diastereomers were not separated. The elution order appears to be regulated by configuration, a finding which may allow peak identification in the absence of isomer standards. When coupled with electron capture detection, the developed methods had low detection limits and may be used for analysis of SP diastereomers and enantiomers in environmental samples. 相似文献
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Experiments were conducted to study the influences of synthetic bayerite, non-crystalline aluminum oxide (N-AlOH), goethite, non-crystalline iron oxide (N-FeOH) and kaolinite on the adsorption, activity, kinetics and thermal stability of invertase. Adsorption of invertase on iron, aluminum oxides fitted Langmuir equation. The amount of invertase held on the minerals followed the sequence kaolinite > goethite > N-AlOH > bayerite > N-FeOH. No correlation was found between enzyme adsorption and the specific surface area of minerals examined. The differences in the surface structure of minerals and the arrangement of enzymatic molecules on mineral surfaces led to the different capacities of minerals for enzyme adsorption. The adsorption of invertase on bayerite, N-AlOH, goethite, N-FeOH and kaolinite was differently affected by pH. The order for the activity of invertase adsorbed on minerals was N-FeOH > N-AlOH > bayerite > reak goethite > kaolinite. The inhibition effect of minerals on enzyme activity was kaolinite > crystalline oxides > non-crystalline oxides. The pH optimum of iron oxide- and aluminum oxide-invertase complexes was similar to that of free enzyme (pH 4.0), whereas the pH optimum of kaolinite-invertase complex was one pH unit higher than that of free enzyme. The affinity to substrate and the maximum reaction velocity as well as the thermal stability of combined invertase were lower than those of the free enzyme. 相似文献
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开发建设项目水土保持设施竣工验收程序和方法 总被引:2,自引:1,他引:2
开发建设项目水土保持设施的竣工验收 ,要严格遵循水利部《开发建设项目水土保持设施验收管理办法》 ,坚持验收合格的 4条标准 ,由具备资质的机构进行验收前的技术评估 ,验收程序和方法要符合国家验收规程的规定与要求 相似文献
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中国水土保持生态环境建设现状与社会经济可持续发展对策 总被引:19,自引:3,他引:16
水土流失是中国头号生态环境问题,已成为社会经济可持续发展的制约因素。从防灾减灾的角度出发,分析了中国水土流失的现状、存在问题,总结了中国水土保持工作的成绩、经验,提出了新形势下进一步加强水土保持生态环境建设的对策。 相似文献