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1.
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
2.
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
3.
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
4.
The effects of biochar (maize biochar – MBC, wood biochar – WBC) and unfermented or fermented hydrochar (HTC) on the euedaphic Collembola Protaphorura fimata and on spring wheat were investigated in greenhouse experiments. The impact of char type, amount of fermented HTC, and MBC-Collembola interactions were assessed. Generally, shoot and root biomass as well as abundance of P. fimata were not affected by the different chars. However, with increasing amounts of fermented HTC the abundance of P. fimata declined, whereas shoot biomass of wheat increased. Moreover, MBC altered root morphology and resulted in thicker roots with higher volume. The latter was not apparent when Collembola were present. 相似文献
5.
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
6.
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
7.
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
8.
大豆植株性状相关性与产量回归分析 总被引：11，自引：1，他引：10
本文利用3个大豆品种、4种施肥模式条件下,植株产生的17个形态指标及产量差异,进行相关性分析与产量回归分析。结果表明,株高x1、分枝数x5、1粒荚数x9、2粒荚数x10、3粒荚数x11、4粒荚数x12、百粒重x15、经济系数x16等8个大豆植株性状因子对产量有显著性影响;由标准化回归系数得知,对产量作用的大小顺序为:x11>x12>x9>x10>x16>x15>x1>x5。说明提高大豆产量首先要考虑增加有效荚数,其次是提高经济系数,而增加百粒重和株高对于增产的效应较小。育种上需加强生物量大、3粒荚和4粒荚数多、结荚节位低的性状选择;栽培上需注重促进生物量生长、降低结荚节位的促控措施。 相似文献
9.
三氯生与镉单一及复合污染对土壤呼吸和酶活性的影响 总被引：1，自引：0，他引：1
为了解典型药品和个人护理品(PPCPs)——三氯生与镉复合污染的生态效应,采用室内培养实验和联合毒性预测模型,首次评价了三氯生与镉单一及复合污染对土壤呼吸及参与土壤碳氮循环的相关酶活性的生态毒性。结果表明:三氯生与镉单一及复合污染对土壤呼吸呈现激活—抑制—激活的生态效应;刺激了蛋白酶活性,激活率先降低后升高,56 d时达到最大。整个实验期间均抑制了蔗糖酶活性,镉(10.0 mg kg-1)单一污染培养14 d抑制率达到最大值(81%),三氯生单一胁迫呈现负的剂量效应关系,两者复合污染无显著的剂量效应关系。联合效应评价模型预测表明,相比三氯生或镉单一污染,两者的复合胁迫对土壤呼吸呈现随时间变化的拮抗—协同—加和效应,对土壤蛋白酶呈现协同—加和—协同的联合效应,而对土壤蔗糖酶活性则主要为协同效应。 相似文献
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11.
黄土高原旱地土壤微量元素硒锌钼潜在缺乏,不仅影响农作物产量,还降低农产品的矿物营养品质,研究施用硒锌钼肥料对该地区作物生长及可食部分营养元素含量的影响具有重要意义。通过田间试验,研究了硒锌钼肥单独土施、硒锌肥配施、硒锌钼肥配施对马铃薯和小白菜产量及营养元素和硒镉含量的影响。结果表明：硒肥提高了马铃薯块茎和小白菜叶片硒含量,分别由对照的0.02mg.kg-1和0.09mg.kg-1提高到1.51～2.15mg.kg-1和13.03～19.44mg.kg-1,钼肥提高了马铃薯块茎和小白菜叶片钼含量,分别由对照的0.43mg.kg-1和2.3mg.kg-1提高到1.03～1.16mg.kg-1和17.7～19.9mg.kg-1,单施与配施处理间无显著差异。锌肥土施或锌与硒、钼肥配合土施不但使小白菜叶片中的锌含量由对照的21.0mg.kg-1显著提高到48.1～68.4mg.kg-1,还使镉含量显著降低50%以上;施锌对马铃薯块茎的锌含量无显著影响。硒锌钼肥单施或配施均对马铃薯和小白菜产量及氮、磷、钾、硫、钙、镁、铁、锰、铜、硼含量无显著影响。因此,在黄土高原旱地,硒钼配合土施可同时提高马铃薯块茎的硒钼含量,硒锌钼配合土施可同时提高小白菜叶片的硒锌钼含量。 相似文献
12.
施氮量对杂交棉氮、磷、钾吸收利用和产量及品质的影响 总被引：11，自引：2，他引：9
在高产条件下,研究了不同施氮量对杂交棉氮、磷、钾的吸收利用和产量及品质的影响。结果表明,增施氮肥显著提高了杂交棉氮、磷、钾的积累量,特别是显著提高了杂交棉后期氮、磷、钾的积累量和积累比例。施氮量N300 kg/hm2的子棉产量最高,比施氮量N 225 kg/hm2处理增产0.9%,但差异不显著。氮、磷、钾养分利用效率随施氮量增加而提高;但氮肥利用率随施氮量的增加而下降。施氮可以显著提高纤维长度和纤维比强度,而不同施氮量处理间纤维长度和比强度差别不大。 相似文献
13.
赣州市水土流失面积1964-1988年呈增长趋势,1988年以后呈减少趋势,章、贡两江输沙量1988年以后逐渐减少,尤其是1998年以来显著减少。事实证明,人为破坏、重治轻防是水土流失加剧的根本原因,预防为主、综合防治是我市水土保持的成功之路。40年来水土流失与章、贡两江水沙变化态势是赣州市水土保持工作的客观反映。 相似文献
14.
P. BLACKWELL S. JOSEPH P.MUNROE H. M. ANAWAR P. STORER R. J. GILKES Z. M. SOLAIMAN 《土壤圈》2015,25(5):686-695
The high price of synthetic fertilisers and the price
barrier for biochar as a soil amendment have encouraged the
exploration of using biochar in fertiliser replacement
formulations. Biochars coupled with fertilisers can be
applied at lower application rates to achieve benefits in
plant growth and nutrition, as well as soil biological
fertility.~It is necessary to evaluate the use of biochar
as a fertiliser substitute.~Therefore, this study
investigated the comparative influences of biochars,
including {\it Acacia saligna} (AS), Simcoa jarrah (SJ) and
Wundowie jarrah (WJ), mineral fertiliser with microbes (MF
+ M), biochar-mineral complex (BMC) and their combination
on mycorrhizal colonisation, growth and nutrition of wheat
in a glasshouse experiment and sorghum in field conditions.
BMC + MF + M treatment produced higher mycorrhizal
colonisation than MF + M alone, indicating that BMC had a
significant role in increasing mycorrhizal colonisation.~SJ
(treated with acetic acid) and MF + M treatments, as well
as AS + MF + M application, showed si\-milar effects on
mycorrhizal colonisation, but lower colonisation than the
BMC~+~MF~+~M treatment.~Overall, the BMC + MF + M treatment
supported the maximum shoot, root and total plant dry
weight followed by AS + MF + M and WJ + MF + M. The~MF + M
treatment had the maximum shoot N and K concentrations,
while BMC + MF + M application had the maximum shoot P
concentration. AS + MF + M and WJ + MF + M treatments
supported the maximum N uptake by wheat shoots, while BMC +
MF + M supported the maximum P uptake.~The results showed
that biochars and BMCs could increase mycorrhizal
colonisation, plant growth and nutrient uptake of wheat,
particularly N, P, K, S and Zn. The field experiment
confirmed that BMC application at a rate of 300 kg
ha$^{-1}$ could increase the yield of irrigated sorghum on
a loam soil and provide better applied P use efficiency
compared to a water-soluble fertiliser alone. These results
indicated that biochar-based fertilisers might increase the
resilience and sustainability of dryland cropping in
environments such as in Western Australia and warrant
further field evaluation. 相似文献
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16.
通过盆栽试验研究钼硒配施对水培小白菜钼硒形态及硒价态的影响。结果表明:施硒增加了小白菜地上部及地下部醇溶态和水溶态钼含量,降低了小白菜地上部及地下部盐溶态及醋酸溶态钼的含量,增加了地下部盐酸溶态钼含量,对地上部盐酸溶态钼含量没有太大的影响。施钼对小白菜地上部醇溶态、水溶态硒含量影响不大,增加了盐溶态及盐酸溶态硒的含量,降低了醋酸溶态硒的含量;施钼对小白菜地下部醇溶态硒含量影响不大,降低了水溶态硒的含量,增加了盐溶态、醋酸溶态及盐酸溶态硒的含量。施用四价的亚硒酸钠对小白菜可食部位硒的有机化较为有利,并且施钼也能促进高硒水平下小白菜体内硒的有机化。因此,钼硒配施虽然对小白菜体内钼和硒的各赋存形态有拮抗作用也有协同作用,但是有利于生产富含有机硒的作物。 相似文献
17.
氮锌互作对水稻产量及籽粒氮、锌含量的影响 总被引：10，自引：2，他引：8
为探明氮锌互作对水稻产量及氮、锌含量的影响,以镇稻11号为供试材料,在大田条件下研究了2个氮肥用量（N 200、300 kg/hm2）下6个施锌水平（ZnSO47H2O 0、10、25、50、100、150 kg/hm2） 对水稻产量及成熟期植株氮、锌浓度及累积量的影响。试验结果表明: 在本试验条件下,锌肥的施用对水稻产量的增加不显著,但施锌能显著提高水稻各部位的锌浓度和籽粒锌累积量,并能提高水稻籽粒的氮浓度和粗蛋白含量,且表现出随施锌量的增加籽粒的氮浓度和粗蛋白含量增加的趋势; 高施氮量有利于水稻的增产及对锌的吸收与累积。因此,氮锌配施具有增加籽粒锌富集和提高蛋白质含量的双重效益。 相似文献
18.
欧李多酚提取纯化及抗氧化性研究 总被引：5，自引：4，他引：1
欧李富含钙素和多酚类物质,具有提高人体免疫力等保健功能,近年来在中国得到了大力发展。该研究欧李多酚提取、纯化及其抗氧化功能,为欧李开发利用提供理论依据。该研究采用单因素及响应面优化试验研究了欧李多酚超声辅助酶解提取工艺,采用大孔树脂纯化多酚粗提物,利用高效液相色谱法测定酚类物质的种类,利用分光光度法测定欧李多酚类物质总还原力和对自由基.OH、DPPH·、ABTS·的清除作用。试验得出欧李多酚提取最优工艺参数为：超声波功率105 W、酶解温度50 ℃、酶解时间80 min、液料比30∶1(mL/g）,多酚提取量为42.63 mg/g。经大孔树脂纯化后纯化物中欧李总多酚含量为73.42 mg/g,从欧李果实中检测出6种多酚类物质,其含量顺序为绿原酸>没食子儿茶素没食子酸酯>咖啡因>对羟基苯甲酸>原儿茶酸>没食子酸。欧李多酚的总还原力与维生素C相当,对.OH、DPPH.、ABTS.等自由基清除作用显著。 相似文献
19.
选取两种益生菌(巨大芽孢杆菌和解淀粉芽孢杆菌)分别与化肥和蚓粪配施,研究了蚓粪和益生菌配施对设施蔬菜地土壤化学性状、酶活性及菠菜产量和品质的影响。结果表明:在等养分条件下与单施化肥相比,蚓粪能够显著提高土壤有效磷含量及p H值,降低速效钾、铵态氮含量及EC值,有利于土壤脲酶、蛋白酶和过氧化氢酶活性的提高,有效改善菠菜品质;与单施蚓粪相比,益生菌与蚓粪配施不仅显著提高土壤硝态氮含量、蔗糖酶活性,还增加了土壤EC值,提高了菠菜可溶性糖、蛋白及维生素C含量,且解淀粉芽孢杆菌配施蚓粪还增加了菠菜产量;而益生菌配施化肥对菠菜产量增加和品质改善效果不及益生菌配施蚓粪效果显著。综合比较两种益生菌和蚓粪配施效果,以蚓粪配施解淀粉芽孢杆菌对土壤性状改善和蔬菜产量、品质提高效果最好。 相似文献
20.
采用盆栽试验的方法,研究不同磷添加量(0,20,80 mg/kg)和土霉素添加量(0,40,160 mg/kg)对小麦和紫花苜蓿幼苗生物量及根系发育的影响。结果表明:所有水平土霉素处理中,20,80 mg/kg磷处理的小麦地上部生物量均比不加磷时高,分别高22.7%～34.1%,10.0%～30.0%和9.1%～18.3%。除160 mg/kg土霉素加80 mg/kg磷的处理外,所有处理的苜蓿根生物量均小于不加磷和土霉素的对照。小麦的根长和根表面积随着土霉素添加量的增加总体上呈减少的趋势。总体来看,施磷显著促进了小麦幼苗地上部的生长,但对苜蓿幼苗生长的影响不显著。土霉素对苜蓿幼苗的根系发育有抑制作用。研究结果可为评价土壤中土霉素残留对作物早期生长的影响和指导合理施用磷肥提供理论依据。 相似文献