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紫色土池塘养殖底泥理化性质变化及营养沉积过程 被引量:2
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作者 李天才 余米 +3 位作者 江瑞 赵晴云 付梅 苏胜齐 《河南农业科学》 北大核心 2022年第4期151-159,共9页
为探讨紫色土池塘养殖进程中底泥理化性质变化及营养沉积过程,以重庆市铜梁区(N29.5130°,E106.4010°)采集的紫色土作为基础,覆水模拟紫色土池塘半年的养殖过程,定期测定底泥温度、pH值、氧化还原电位等理化指标和有机质、氮... 为探讨紫色土池塘养殖进程中底泥理化性质变化及营养沉积过程,以重庆市铜梁区(N29.5130°,E106.4010°)采集的紫色土作为基础,覆水模拟紫色土池塘半年的养殖过程,定期测定底泥温度、pH值、氧化还原电位等理化指标和有机质、氮、磷、钾、镁、硫等营养成分含量。结果表明,石灰性紫色土pH值达8.5,碱性明显,营养总体偏低。建成池塘后底泥迅速向中性转化,养殖组pH值(7.1)明显低于对照组(7.3);养殖组底泥表现为还原性,氧化还原电位降至约-210.0 mV,明显低于对照组(180.0 mV)。养殖组底泥主要营养成分有机质、总氮、总磷、速效磷和速效钾等含量逐步升高,均高于对照组,试验结束时沉积量分别达5.10 g/kg、0.13 g/kg、0.45 g/kg、78.88 mg/kg和88.50 mg/kg;其他营养成分也有不同量沉积,仅镁含量降低。养殖组底泥有机质不断累积并发生厌氧反应,但底泥p H值中后期较为稳定且仍处在宜渔区间,表现出石灰性紫色土作为池塘底泥的较强缓冲性。按照底泥有机质5.1 g/(kg·a)沉积和碳氮比升高的速度,养殖3 a后其将变为低渔产力池塘,故建议新建石灰性紫色土池塘养殖清淤年限不应超过3 a。 展开更多
关键词 石灰性紫色土 池塘底泥 模拟养殖 理化性质变化 营养元素沉积
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Benthic nutrient recycling in shallow coastal waters of the Bohai Sea 被引量:8
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作者 刘素美 张经 +1 位作者 陈洪涛 T.Raabe 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2004年第4期365-372,共8页
Sediment-water fluxes of N and P species in the Bohai Sea were investigated in Septem-ber-October 1998 and April-May 1999. The benthic fluxes of nutrient species were determined by incubating sediment core samples wit... Sediment-water fluxes of N and P species in the Bohai Sea were investigated in Septem-ber-October 1998 and April-May 1999. The benthic fluxes of nutrient species were determined by incubating sediment core samples with bottom seawater bubbled with air or nitrogen. -2NO,+4NH, dissolved organic nitrogen (DON) and phosphorus (DOP), total dissolved nitrogen (TDN) and phosphorus (TDP), and -34PO showed a net exchange flux from seawater to sediment, while -3NO, dissolved inorganic nitrogen (DIN) and -23SiO were released from sediment to seawater in the Bohai Sea. Sediment-water nutrient exchange increases DIN and reduces the phosphorus load in the Bohai Sea. The release of silicate from sediment to overlying seawater reduces potential silicate limitation of primary production resulted from decrease of riverine discharge. The exchange flux of nutrients showed no obvious seasonal variation. The present study showed that the concentrations and composition of nutrients in the water column were affected by suspended sediment, and that not all the exchangeable phosphate in sediment could be released via sediment resuspension. 展开更多
关键词 sediment-water exchange nutrient elements adsorption RELEASE Bohai Sea
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Degradation of Soils in the Lowland of Kur-Araz
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作者 E. A. Gurbanov S. A. Ganiyeva 《Journal of Agricultural Science and Technology(A)》 2011年第2X期249-254,共6页
The research works were carried out for determination of the washout, types, sorts and level of the development reasons of degradation with the purpose of preparation of the measures of fight against degradation in th... The research works were carried out for determination of the washout, types, sorts and level of the development reasons of degradation with the purpose of preparation of the measures of fight against degradation in the soils in 2005-2009 in the lowland of Kur-Araz. The investigations were fulfilled by using of geographical and stasionar methods. It is revealed that 333.6 thous, ha of the soils of the lowland of Kur-Araz have been exposed to erosion. 97.4 thousand ha of them have been exposed to rainstorm erosion, 127.1 thous, have been exposed to irrigative and 122.1 thous, ha to wind erosion. The most dangerous of them are considered irrigative erosion. Under the influence of erosion process in deposited over the length of furrow, deposits the changes happened in maintenance of humus and nutritions elements. In dependence on slope and water expenditure on 1 ha 2.23-14.86 t of soil are leached. As a result of out wash from 1 ha of soil 55.88-304.59 kg of humus, 4.06-20.80 kg of nitrogen, 4.57-26.55 of phosphorus and 57.40-372.99 of potassium are lost. The soil is exposed to degradation and as a result a process of desertification begins. On the basis of the quantitative an intensity of soil outwash the possible losses of dry matter including humus and main elements of nutrition of plants as a result of erosion, their deposit with the water way, are calculated, too. 展开更多
关键词 Irrigative erosion erosion degradation wind erosion defination capacity removal of humus.
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