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| 1 | 保护性耕作对农田碳、氮效应的影响研究进展显示文摘作物产量的高低主要取决于土壤肥力,如何保持并提高土壤肥力是确保我国粮食安全和农业可持续发展的重要任务,也是众多学者关注的焦点。土壤有机碳和氮素是评价土壤质量的重要指标,其动态平衡直接影响土壤肥力和作物产量。随着全球气候变化及环境污染问题的愈加突出,农田土壤固碳及提高氮效率成为各界科学家研究的热点。目前,保护性耕作已成为发展可持续农业的重要技术之一,对土壤固碳及氮素的利用具有很大的影响。深入了解保护性耕作对土壤有机碳固持与氮素利用效率提高的影响机制,对于正确评价土壤肥力有着重要意义。但由于气候、土壤及种植制度等条件不一致,关于保护性耕作对农田碳、氮效应结论不一。阐述了国际上保护性耕作对农田系统土壤有机碳含量变化及其分解排放(如CO2和CH4)、氮素变化及其矿化损失(如NH3挥发、N2O排放与氮淋失)和碳氮素相互关系(如C/N层化率)影响的研究进展,并分析了其影响因素和相关机理。尽管国内保护性耕作的研究已进行30多年,但在土壤有机碳与氮素方面与国外相比依然有较大的差距。保护性耕作对土壤固碳与氮素利用的影响机制,碳素和氮素在土壤-植株-大气系统中的转移变化,及结合农事管理等综合评价其生态效应的研究很少。在此基础上,提出未来我国保护性耕作在土壤有机碳固定和氮素利用方面的重点研究方向:(1)在定位试验基础上进一步探讨保护性耕作对土壤有机碳及氮素利用的影响机制;(2)深入研究土壤有机碳和氮素的相互关系及其对土壤肥力的影响;(3)结合环境保护与土壤可持续管理对保护性耕作农田土壤固碳及氮素高效利用的系统评价研究;(4)加强保护性耕作对农田碳、氮效应的宏观研究,合理评价保护性耕措施下对农田碳、氮综合效应。 | 薛建福 赵鑫 Shadrack Batsile Dikgwatlhe 陈阜 张海林 | 2013 | 生态学报2013，33，19： | 58 |
| 2 | Applying a salinity response function and zoning saline land for three fi eld crops: a case study in the Hetao Irrigation District, Inner Mongolia, China显示文摘Salinity is one of the major abiotic factors affecting the growth and productivity of crops in Hetao Irrigation District, China. In this study, the salinity tolerances of three local crops, wheat(Triticum aestinum L.), maize(Zea mays L.) and sunflower(Helianthus annuus L.), growing in 76 farm fields are evaluated with modified discount function. Salinity ecological zones appropriate for these local crops are characterized and a case study is presented for crop salinity ecological zoning. The results show that the yield reductions of wheat, maize and sunflower when grown in saline soils are attributed primarily to a reduction in spikelet number, 1 000-grain weight and seed number per head, respectively. Sunflower is the most tolerant crop among the three which had a salinity tolerance index(ST-index) of 12.24, followed by spring maize and spring wheat with ST-Indices of 9.00 and 7.43, respectively. According to the crop salinity tolerance results, the arable land in the Heping Village of this district was subdivided into four salinity ecological zones: the most suitable, suitable, sub-suitable and unsuitable zones. The area proportion of the most suitable zone for wheat, maize and sunflower within the Heping Village was 27.5, 46.5 and 77.5%, respectively. Most of the most suitable zone occurred in the western part of the village. The results of this study provide the scientific basis for optimizing the local major crop distribution and improving cultural practices management in Hetao Irrigation District. | TONG Wen-jie CHEN Xiao-li WEN Xin-ya CHEN Fu ZHANG Hai-lin CHU Qing-quan Shadrack Batsile Dikgwatlhe | 2015 | Journal of Integrative Agriculture2015，14，1： | 3 |
| 3 | Archives and Records Management Education and Training:What Can Africa Learn from Europe and America? 显示文摘 | Shadrack Katuu | 2009 | Information Development2009，，25： | 1 |
| 4 | Flotation of coarse composite particles in mechanical cell vs. the fluidised-bed separator (The HydroFloat?)显示文摘 | Shadrack Fosu Bellson Awatey William Skinner Massimiliano Zanin | 2015 | Minerals Engineering2015，，： | 1 |
| 5 | Measuring, modeling and mapping ecosystem services in the Eastern Arc Mountains of Tanzania显示文摘 | Fisher Brendan Turner R Kerry Burgess Neil D Swetnam Ruth D Green Jonathan Green Rhys E Kajembe George Kulindwa Kassim Lewis Simon L Marchant Rob Marshall Andrew R Madoffe Seif Munishi PKT Morse-Jones Sian Mwakalila Shadrack Paavola Jouni | 2011 | Progress in Physical Geography2011，，5： | 1 |
| 6 | 加纳农业机械化发展潜力及制约因素(摘选) | Shadrack Kwadwo Amponsah Patricia Oteng-Darko Francis Kumi | 2012 | 农业工程2012，2，8： | 1 |
| 7 | Inhibitory potentials of phenolic-rich extracts from Bridelia ferruginea on two key carbohydrate-metabolizing enzymes and Fe^(2+)-induced pancreatic oxidative stress显示文摘Objective: The current study was designed to evaluate the various antioxidant potentials and inhibitory effects of phenolic-rich leaf extracts of Bridelia ferruginea(BF) on the in vitro activities of some key enzymes involved in the metabolism of carbohydrates.Methods: In this study, BF leaf free and bound phenolic-rich extracts were used. We quantified total phenolic and flavonoid contents, and evaluated several antioxidant activities using assays for ferric reducing antioxidant power, total antioxidant activity(phosphomolybdenum reducing ability), 1,1-diphenyl-2-picrylhydrazyl and thiobarbituric acid reactive species. Also, extracts were tested for their ability to inhibit a-amylase and α-glucosidase activity.Results: The total phenolic and total flavonoid contents in the free phenolic extract of BF were significantly greater than in the bound phenolic extract. Also, all the antioxidant activities considered were significantly greater in the free phenolic extract than in the bound phenolic extract. In the same vein, the free phenolic-rich extract had a significantly higher percentage inhibition against α-glucosidase activity(IC_(50)= 28.5 mg/mL) than the bound phenolic extract(IC_(50)= 340.0 mg/mL). On the contrary, the free phenolic extract(IC_(50)= 210.0 mg/mL) had significantly lower inhibition against α-amylase than the bound phenolic-rich extract(IC_(50)= 190.0 mg/mL).Conclusion: The phenolic-rich extracts of BF leaves showed antioxidant potentials and inhibited two key carbohydrate-metabolizing enzymes in vitro. | Olakunle Bamikole Afolabi Omotade Ibidun Oloyede Shadrack Oludare Agunbiade | 2018 | Journal of Integrative Medicine2018，16，3： | 0 |
| 8 | 儿童照管、家庭禀赋与女性非农就业——基于CFPS的数据分析显示文摘利用2014年中国家庭追踪调查(CFPS)数据分析儿童照管对女性非农就业的影响,并探究了家庭禀赋缓解两者间的阻碍作用。结果表明,儿童照管对农村女性非农就业具有重要且显著的抑制作用,而家庭经济资本和人力资本可以部分减少农村女性照管儿童的成本,有助于缓解这一抑制作用。另外,从农村女性年龄、儿童年龄和儿童白天的照管方角度展开异质性分析,再一次证明儿童照管对农村女性非农就业的阻碍作用。这一结果反映了现阶段中国农村依旧存在部分因需要照管儿童而未进入非农就业市场的农村女性劳动力,而提升家庭禀赋则有利于将这些重要劳动力从中释放出来,对调整劳动力市场结构、提高家庭经济生活水平和幸福感及农村女性寻找家庭和工作的平衡点具有现实意义。 | 韩纪琴 Kipkogei Shadrack 韩冰 苗欣茹 | 2023 | 湖北农业科学2023，62，9： | 0 |
| 9 | Maize (Zea mays L.) Growth and Grain Yield under Conventional and Site-Specific Nitrogen Management in a Dryland Farming System显示文摘 | Suzan Mashego Brilliant Mareme Petja Matshwene Edwin Moshia Shadrack Batsile Dikgwatlhe | 2014 | Journal of Agricultural Science and Technology(B)2014，4，8： | 0 |
| 10 | Effect of Browsing on the Growth of Jojoba Seedlings in the Dry-Lands of Kenya显示文摘Jojoba is a desert shrub,introduced in the marginal areas of Kenya during 1980s.Jojoba domestication is being faced by browsing problems due to pastoralism in these areas.Massive browsing of leaves lowers photosynthesis leading to decline in plant functions.An experiment was set up in Maungu,with the aim of determining the effect of browsing on jojoba seedlings.The experimental design was a randomized complete block design with three treatments replicated three times.The treatments consisted of varying levels of browsing as follows:non browsed,50%browsed and fully browsed.Seedlings were raised for six months before sampling.Variables assessed were:survival,height,root-collar diameter,leaf size,root length and number,internode length,sprout number,root/shoot ratio and total biomass.ANOVA was performed to determine differences among the treatments whilst significant differences among the means were separated using least significant difference(LSD)at p≤0.05.Results showed fully browsed seedlings were significantly lower in height(26.2 cm),internode length(9.7 mm),leaf length(18.3 mm)and width(10.4 mm)and total fresh plant biomass(11.0 g)compared to the non browsed ones which showed 31.1 cm,23.2,36.1 and 16.6 mm and 17.8 g,respectively.On the other hand,fully browsed seedlings showed significantly higher root/shoot ratio.Seedling growth was negatively affected by severity of browsing which resulted in stunted growth.The study recommended that browsing of seedlings should be prevented since it hinders plant growth. | Shadrack Kinyua Inoti | 2018 | Journal of Agricultural Science and Technology(B)2018，8，5： | 0 |
| 11 | K-Hyperparameter Tuning in High-Dimensional Space Clustering:Solving Smooth Elbow Challenges Using an Ensemble Based Technique of a Self-Adapting Autoencoder and Internal Validation Indexes显示文摘k-means is a popular clustering algorithm because of its simplicity and scalability to handle large datasets.However,one of its setbacks is the challenge of identifying the correct k-hyperparameter value.Tuning this value correctly is critical for building effective k-means models.The use of the traditional elbow method to help identify this value has a long-standing literature.However,when using this method with certain datasets,smooth curves may appear,making it challenging to identify the k-value due to its unclear nature.On the other hand,various internal validation indexes,which are proposed as a solution to this issue,may be inconsistent.Although various techniques for solving smooth elbow challenges exist,k-hyperparameter tuning in high-dimensional spaces still remains intractable and an open research issue.In this paper,we have first reviewed the existing techniques for solving smooth elbow challenges.The identified research gaps are then utilized in the development of the new technique.The new technique,referred to as the ensemble-based technique of a self-adapting autoencoder and internal validation indexes,is then validated in high-dimensional space clustering.The optimal k-value,tuned by this technique using a voting scheme,is a trade-off between the number of clusters visualized in the autoencoder’s latent space,k-value from the ensemble internal validation index score and one that generates a value of 0 or close to 0 on the derivative f″′(k)(1+f′(k)^(2))−3 f″(k)^(2)f″((k)2f′(k),at the elbow.Experimental results based on the Cochran’s Q test,ANOVA,and McNemar’s score indicate a relatively good performance of the newly developed technique in k-hyperparameter tuning. | Rufus Gikera Jonathan Mwaura Elizaphan Muuro Shadrack Mambo | 2023 | Journal on Artificial Intelligence2023，5，1： | 0 |
| 12 | Environmental Flow Assessment of Great Ruaha River in Southwestern Part of Tanzania显示文摘 | Shadrack Mwakalila Petro Masolwa | 2012 | Journal of Environmental Science and Engineering(A)2012，1，3： | 0 |
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