搜索结果: 76-90 共查到“知识库 土壤耕作学”相关记录316条 . 查询时间(2.625 秒)
Diversity of shifting cultivation cycles among small-scale farmers in Peruvian Amazon
Agroforestry Deforestation Land Degradation Slash-And-Burn Swidden-Fallow
2013/3/4
Although shifting cultivation is practiced by millions of farmers, it is often blamed for caus-ing deforestation and keeping farmers in pov-erty. Our study focused on the Amazon basin, where small-sca...
Water use efficiency and yield of winter wheat under different irrigation regimes in a semi-arid region
Water Use Efficency Yield Surface and Drip Irrigation
2013/3/4
In irrigation schemes under rotational water supply in semiarid region, the water allocation and irrigation scheduling are often based on a fixed-area proportionate water depth with every irrigation c...
氮素运筹对玉米干物质积累、氮素吸收分配及产量的影响
氮素 玉米 吸收分配 产量
2012/2/20
田间小区试验，研究了氮素运筹对玉米干物质累积、氮素吸收分配及产量的影响。结果表明，施氮和有机肥可以延长干物质积累的旺盛时期，使玉米干物质总量积累速率最大的时刻推后1～3d，增加了玉米的干物质积累量。氮肥配施有机肥能延长氮素积累的旺盛时期，其中，N2+M处理氮素积累的旺盛时期△t分别比N0、N1、N2、N3和FP处理延长了6、4、6、1和7d，该时段吸N量比FP处理增加 0.25 g/plant，比...
Effects of different material coatings on the wearing of plowshares in soil tillage
Metal coating plowshare plow tillage wear
2011/6/29
The wearing behavior of coated layers on plowshares used in soil tillage was investigated. Plowshares produced from DIN EN 10 083 (30 MnB5) steel, widely used in plows, were coated with 20 mm hard chr...
基于粮食安全角度的三峡库区耕地保护研究——以重庆市巫山县为例
粮食安全角度 三峡库区耕地保护
2011/9/13
耕地的数量是粮食生产能力的核心要素，为保障三峡库区粮食战略安全及民生稳定，保护耕地是关键。笔者以库区巫山县为例，采用粮食安全耕地面积模型，综合分析人口、粮食单产、农业结构调整、建设占用耕地等因素，预测2010年、2020年巫山县耕地需求量及有效耕地供给量。分析得出，巫山县2010年、2020年耕地需求量分别为33428.57 hm2、33391.25 hm2；耕地可供给量分别为41102.82 h...
黑土区是中国重要的商品粮生产基地之一，对于中国的粮食安全和国民经济的稳定起着举足轻重的作用。此文以松嫩耕作黑土土壤为研究对象，对呼兰、绥化、海伦、依安与嫩江5个调查区的土壤中Cu、Pb、Zn的污染现状进行研究，揭示耕作黑土的健康状况，为黑土生态系统的科学管理提供理论依据。采用内梅罗综合污染指数法及TOPSIS法进行环境质量综合评价。结果表明：土壤Cu、Pb、Zn的污染程度，由东南至西北未表现出明显...
日光温室蔬菜栽培对土壤团聚体稳定性的影响——以陕西省泾阳县日光温室土壤为例
温室栽培 团聚体 机械稳定性 水稳性
2011/6/8
土壤的团聚状况是土壤重要的物理性质之一，团聚体的数量是衡量和评价土壤肥力的重要指标。用干筛法、湿筛法及带水振荡法对温室土壤和露地土壤的团聚体含量进行了测定。根据干筛法测得的各级团聚体含量及MWD指标的评判，温室土壤团聚体的机械稳定性低于露地土壤；根据>0.25mm水稳性团聚体含量、水稳性团聚体的MWD值、团聚体的破坏率及团聚体的原始稳定系数和崩解速率等指标评判，温室土壤团聚体的水稳性高于露地土壤，...
Herbicidal Activity of Mycelial and Cell Free Extracts of Fusarium oxysporum F.sp.Ciceris Against Rice Weed Cyperus Iria l
Herbicidal Activity Mycelial Cell Free Extracts Fusarium oxysporum F.sp. Ciceris Rice Weed Cyperus Iria l
2010/12/16
Herbicidal Activity of Mycelial and Cell Free Extracts of Fusarium oxysporum F.sp.
Ciceris Against Rice Weed Cyperus Iria l。
Effects of Soil Compaction by Tractor Traffic on reclaimed soil in Isahaya Bay
reclaimed field of Isahaya Bay soil compaction
2010/12/3
At a reclaimed field of Isahaya Bay, a vehicle running test was conducted using tractors, and the penetration resistance (cone index) of soil before and after the running was compared. From this resul...
以杂交玉米蠡玉16和冀单28为供试作物，采用供高磷（250 μmol/L）和低磷（5 μmol/L）营养液的石英砂培养方法，研究2个玉米品种的各器官干重和磷积累与分配、体内磷在木质部和韧皮部中的循环、流动及磷的吸收和利用效率。结果表明，与供高磷处理相比，低磷处理的2个玉米品种各营养器官的干重、磷含量和木质部中运输的磷量显著降低; 而磷在体内韧皮部的再循环显著增加，并且玉米各部位叶片活化出的磷主要是...
Assessment of metals accumulated in Durum wheat (Triticum durum Desf.), pepper (Capsicum annuum) and agricultural soils
Heavy metals soil contamination sequential extraction
2011/1/12
Soil contamination by heavy metals is widely spread and concerns have been raised over the potential risks to humans, animals and agricultural crops. Toxic metals are readily accumulated in some plant...
Assessing impact of soil management technologies on smallholder farmers’ livelihoods in north western Kenya
Impact assessment soil technologies
2011/1/13
Soil nutrient depletion is a major constraint to agricultural production on smallholder farms in Kenya. Intervention in the depletion through soil management project (SMP) was initiated in 1994 throug...
土壤深度对土磷素淋失的影响
土层深度 渗漏池 磷形态 淋失
2012/3/30
利用渗漏池设施，研究了冬小麦-夏玉米轮作条件下不同土壤深度对土磷素淋失的影响。种植8季作物结果表明，对深度小于80 cm 的渗漏池，淋出土体的累积渗滤液量和累积全磷量随化学磷肥施用量的增加而减少; 随土层深度的增加，淋出土体的渗滤液和磷量均减少，且二者的减少率都很接近，表明磷素淋失主要受通过土体的土壤水分控制。相对于深度小于80 cm的土层，供试土壤的粘化层有效地减少了土壤渗滤液和磷素淋失。各深度...
研究了17年长期定位施用化肥对黄土丘陵区坡耕地土壤物理性质的影响。结果表明: 长期施用化肥，表层（0—15 cm）土壤物理性状没有明显退化，中层（15—30 cm）和下层（30—45 cm）土壤物理性质有不同程度的改善; 长期施用化肥对水稳性团聚体影响大于土壤容重和孔隙度; 团聚体含量和稳定性在表层、中层和下层土壤中均得到不同程度地提高; 容重和孔隙度在表层和下层土壤中略有恶化，在中层土壤上得到改...
An analysis on the production of potato in Turkey according to NUTS level 1 regions
Potato production NUTS level 1 regions Turkey
2011/1/11
This study tried to determine the distribution shares of potato production and reasons of change in distribution with respect to NUTS level 1 regions. For this purpose, 43 year data of regional time s...