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51.
为了选择出可以在基质中安全种植的作物,该文研究了在粉煤灰加酒糟(基质Ⅰ)和粉煤灰加污泥(基质Ⅱ)混合成的基质中添加柠檬酸和熟石灰作为改良剂,对芸豆、豇豆和马铃薯镉含量及产量的影响。结果表明:熟石灰可以提高作物出苗率,柠檬酸对作物出苗率影响不大。熟石灰可以显著提高基质Ⅰ中芸豆和豇豆以及2种基质中马铃薯的产量,柠檬酸降低基质Ⅰ中芸豆和豇豆的产量,达到显著水平,而对马铃薯在2种基质中的产量影响都不显著。熟石灰可以显著降低芸豆和马铃薯果实中镉的含量,柠檬酸却可以显著增加芸豆果实中镉的含量。粉煤灰加酒糟中可以安全种植的作物为芸豆、豇豆和马铃薯;粉煤灰加污泥中可以安全种植的作物为马铃薯。 相似文献
52.
Tree plantation is a proven strategy to improve the salt‐affected soils. However, the efficiency of trees to reclaim the soil varies from species to species. This study was therefore, carried out with the objective of assessing the efficiency of 3‐yr old plantations of Prosopis juliflora (Swartz) D.C. (Mesquite), Eucalyptus tereticornis Sm. (Forest Red Gum) and Dalbergia sissoo Roxb. Ex. D.C. (Indian Rosewood) to improve the sodic soil characteristics in Sultanpur districts of Uttar Pradesh, India (26°10′–26°23′N, 81°50′–82°5′E). Soil samples collected from six depths; 0.0–0.1, 0.1–0.3, 0.3–0.6, 0.6–0.9, 0.9–1.2 and 1.2–1.5 m below the surface, were analysed for chemical and physical properties by following standard methods. The infiltration rate (IR) was determined by double concentric infiltrometer and the permeability by constant head permeameter. The trees were measured for their girth at breast height (at 1.33 m from ground) and crown area within a 100 × 100 m sector at each of the sites selected. There were decreases in soil pH (from 10.06 to 9.64) and exchangeable sodium percentage (from 70.6 to 26.9) at the P. juliflora plantation relative to the E. tereticornis and D. sissoo plantations. The organic carbon and nitrogen content increased from 2.0 and 0.18 g/kg to 3.9 and 0.45 g/kg under P. juliflora at the surface (0.0–0.1 m) layer. There was also more exchangeable Ca2+, Mg2+and K+ at exchange sites and a reduction in exchangeable Na+ 3 yr after establishing the plantations. There was a significant decrease in surface soil (0.1 m) bulk density from 1.66 to 1.37 (t/m3) but an increase in porosity from 41.2 to 46.3% and water holding capacity from 4.3 to 4.8 g/kg. The IR and soil permeability also increased after 3 yr of tree growth. Prosopis juliflora proved more effective than E. tereticornis and D. sissoo in its ability to enrich a sodic soil with organic matter and establishing better soil–water characteristics. 相似文献
53.
J.L. Christiansen S.-E. Jacobsen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(6):539-544
Abstract Sensitivity to photoperiod in quinoa (Chenopodium quinoa Willd.) was studied under controlled conditions to enhance crop adaptation to environments outside its centre of origin. Two varieties, a traditional variety from Bolivia (Real), which will not mature under Danish conditions, and an early maturing variety (Q52), developed for Danish climatic conditions, were used in this reciprocal transfer experiment. Plants were moved from a short daylength of 10 h (SD) to a long daylength of 18 h (LD) and vice versa at set intervals from sowing to 100 days after sowing (DAS). A reaction of LD in time to flowering was observed only in the Bolivian variety Real. Under SD both varieties flowered after 39 DAS. For Real the LD regime resulted in a moderate increase in time to flowering to 44 DAS. The non-sensitive, juvenile period in Real was estimated to be approximately 16 days. In Q52 a moderate increase in the number of leaves was formed on the main stem after flowering at LD, which indicates that some daylength sensitivity remains. The most striking difference occurred during seed filling, when going from SD to LD. In Q52 the time from the end of flowering to maturity increased from 39 to 52 days. Under SD, Real had a seed-filling period similar to Q52, but at LD Real remained with green leaves during seed filling. Hard seed was observed in the still green perigonium 57 days after end of flowering. At this moment re-shooting occurred from the inflorescence, and seed maturity was not reached at the termination of the experiment at 150 DAS. This study shows that flower induction is not a major problem for adaptation of quinoa to North European conditions but that a very strong, daylength sensitive, stay green reaction is the main cause of the late maturity of South American introductions. 相似文献
54.
汽车加油站的技术改造 总被引:1,自引:0,他引:1
针对汽车加油站目前尚存在地下爆炸空间这一重大事故隐患问题,分析了加油站爆炸空间的形式,制定了安全可靠、切实可行的技术改造方案、施工程序、方法,并对改造方案、施工工序提出了具体要求,这为消除事故隐患,保证加油站安全提供了可靠途径。 相似文献
55.
为明确高产氮高效型籼稻品种的籽粒灌浆特性及其与产量和氮素利用的关系,选用高产氮高效型(HYHNE)、高产氮中效型(HYMNE)和低产氮低效型(LYLNE)杂交籼稻品种,在相应最适氮肥水平下,研究3种类型水稻品种籽粒灌浆特性差异及其与产量和氮利用效率的关系。结果表明,籽粒灌浆特性在不同类型品种间和不同粒位间均存在较大差异。强势粒的最大灌浆速率(GRmax)、达到最大灌浆速率时的米粒重(Wmax)和平均灌浆速率(GRmean)均表现为HYHNE>HYMNE>LYLNE,起始生长势(R0)、活跃灌浆期(D)和有效灌浆时间(T99)均表现为HYHNELYLNE>HYMNE, R0、D和T99均表现为HYHNE相似文献
56.
煤矸石山立地条件与林业复垦研究——以山西统配煤矿为例 总被引:5,自引:0,他引:5
煤矸石是我国工业排弃数量最大的固体废弃物,它带来的危害是压占土地、破坏景观、污染环境。山西省作为能源重化工基地,煤矸石的堆积、污染问题尤为突出,改造任务异常艰巨。研究结果表明:煤矸石成山状堆积,仅表层10cm左右有物理风化,下层很难风化;煤矸石山可蓄一定的水分,但地表高温,养分贫瘠,特别是自燃后的矸石强酸高盐,给植被恢复带来了极大的困难;大量煤矸石山的基本出路是进行林业复垦。其适用技术体系包括:①做好水保工程,保留地表黑色风化层;②引入先锋草种、树种;③薄盖土后直播;④加强施肥、病虫害防治等管理。 相似文献
57.
58.
Vesna Zupanc Gerhard Kammerer Helena Gr
man Igor antavec Rozalija Cveji Marina Pintar 《Land Degradation \u0026amp; Development》2016,27(2):406-415
Hydropower plants on the lower river Sava, Slovenia, were developed without sealing the underground upstream. As a consequence, without the countermeasures of elevating and recultivating, the agricultural land on the river banks would be inundated because of the water‐table increase of the river. To remedy this, the fields were elevated and recultivated. The goal of this study was to assess soil quality and production potential after land raising and recultivation and to answer the question whether it is possible to recover soil quality and crop yield after large‐scale mass manipulation, such as land raising. After recultivation and after the second year of land reuse for the two cultures grass–clover mixture and corn on two sites, Middle Pijavsko and Lower Pijavsko, soil physical and chemical characteristics and crop yields were evaluated. Mixing of topsoil with the second horizon during removal and during backfill with filling material resulted in uneven soil fertility, plant growth and decreased yield. Driving on the refilled second layer with heavy machinery caused soil compaction in the Middle Pijavsko in spite of favourable soil texture (loam, 38·7% sand). On the areas with very high sand content (over 55%) and low clay content (10%), soil compaction was not as severe or persistent. Recultivation measures restored the agricultural land almost to the production potential prior to powerplant construction. Immediate intensive land use (corn) showed less favourable effect on soil characteristics. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
59.
为了明确不同熟型玉米籽粒灌浆特性及其对产量的影响,比较研究了中晚熟品种农大108和中早熟品种石玉7号籽粒灌浆动态与产量表现,并对籽粒灌浆特性与籽粒水分的关系进行了分析。结果表明,石玉7号与农大108产量差异显著,百粒重是两品种产量差异的主要原因;石玉7号具有籽粒发育速度快、体积大等特点,前中期(0-45d)灌浆速率始终快于农大108,生育后期(45 d以后)急剧下降。农大108后期灌浆速率则下降缓慢。籽粒发育速度快,灌浆盛期灌浆速度快、强度大是石玉7号百粒重高的主要原因;籽粒水分状况与籽粒灌浆速率关系密切。回归分析表明,籽粒含水百分率在59.47%左右时,石玉7号灌浆速率达到最大值,为9.28 mg/(粒.d);农大108则在57.92%左右时,灌浆速率达到最大值,为8.23 mg/(粒.d)。当籽粒含水百分率下降到某一临界值时,籽粒灌浆停止。两品种收获时,籽粒含水百分率尚远在籽粒灌浆终止临界值以上。 相似文献
60.
水稻灌浆期籽粒中3个与淀粉合成有关的酶活性变化 总被引:72,自引:14,他引:72
在水培和盆栽条件下,研究了6个水稻品种(含籼/粳杂交组合、新株型品系)灌浆期强、弱势粒中ADPG焦磷酸酶(EC2.7.7.21)、淀粉合成酶(EC2.4.1.21)和淀粉分枝酶或Q-酶(EC2.4.1.18)的活性变化及其与灌浆充实的关系。3个酶的活性变化与籽粒灌浆动态相关联:淀粉酶最高活性出现的时间稍前或同步于最大灌浆速率的时间;ADPG焦磷酸酶 相似文献