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排序方式: 共有93条查询结果,搜索用时 15 毫秒
1.
该文阐述了紫穗槐的特性,提出了滨州市推广种植紫穗槐的重要性和可行性,并进行了效益分析。 相似文献
2.
为了明确氮、钾肥对大葱产量和经济效益的影响,开展了多年施用不同数量的氮、钾肥对大葱产量和经济效益的影响试验。结果表明,增施钾肥对大葱生长发育有明显的促进作用,并能显著提高产量。白庙和黄岭地区试验在氮肥(纯N)水平为225、300 kg/hm~2时,大葱经济产量分别增加11.9%~16.8%和13.2%~21.1%,平均分别增长13.9%、16.7%,大葱产量均随钾肥施用量的加大而提高。在氮肥低用量条件下,适当增加氮肥施用量,也能有效提高大葱的经济产量,不同钾肥(K2O)用量下施氮肥大葱可增产9.9%~14.8%,平均增产12.5%;其中,白庙地区大葱产值增收26 160~41 900元/hm~2,产投比为20.22~43.21。 相似文献
3.
氮磷钾肥对陕西关中猕猴桃品质、产量和经济效益的影响 总被引:1,自引:0,他引:1
通过连续3年的田间定位试验,研究了不同氮磷钾肥配比对陕西关中地区猕猴桃品质、产量和经济效益的影响。结果表明,与对照(CK)相比,不同氮、磷、钾配比处理均增加了猕猴桃Vc、可溶性糖含量和单果质量,使猕猴桃产量增加13.6%~30.1%,平均每年可增加产量3.7~8.2 t/hm2,增加纯收入3.1~8.3千元/hm2。氮、磷、钾平衡施用处理在增加叶片中矿物质营养,改善品质,增产和提高经济效益方面效果最佳。氮、磷、钾肥对当地猕猴桃产量的贡献率顺序为氮肥钾肥磷肥,不同肥料配比的纯收入大小顺序为NKKNKNPPK。 相似文献
4.
结合我国水权和水权交易的特点,基于资产评估收益法的理论提出了水权交易价值评估的收益法模型,并对收益额、折现率和收益期限等重要参数进行了说明,为水权交易价值评估提供了一种新思路、新方法。 相似文献
5.
本文根据胶合板厂实际情况,建立了杨木胶合板厂生产规划模型。该模型考虑各主要设备工段、产品组合、产品混合、产品价格、流动资金、原材料供应以及市场约束等问题。本模型能够满足市场竞争,获取最佳利润,同时还能解决胶合板厂“三板”(表、背、芯单板)不平衡问题。 相似文献
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7.
采用田间试验研究不同施钾量对生姜生长、钾素吸收、营养品质及经济效益的影响。结果表明,施用适量钾肥能明显促进生姜生长发育,提高块茎产量、植株含钾量和钾素吸收量,改善营养品质,提高施肥经济效益。2年2地试验结果表明,施钾生姜块茎产量增长13.0%~27.2%和22.3%~37.7%,平均增产22.5%和28.7%,中等钾肥用量的K450处理获得了最高产量;块茎产量与施钾量间呈一元二次抛物线关系。施用不同数量钾肥后,生姜茎叶、姜块和全株含钾量分别提高33.4%~210.7%、2.9%~70.8%和18.4%~139.9%,钾素吸收量增加64.5%~342.2%、31.3%~118.7%和48.5%~209.0%。施用适量钾肥后,生姜块茎粗蛋白质、Vc和可溶性糖含量相应提高,K450处理最高。施钾增收13 626~23 286元/hm2,施用钾肥的产投比高达(2.27~12.60)︰1。 相似文献
8.
为研究木薯皮、鸡粪在蔗区套种模式中的还田施用效果,分别设置化肥配施木薯皮(T1)、配施鸡粪(T2)、配施半量木薯皮和半量鸡粪(T3)3个处理,以甘蔗单种化肥处理(CK1)或甘蔗套种花生化肥处理(CK2)为对照,比较各处理作物产量、品质、效益及花生秸秆还田后土壤肥力的变化。结果表明,T1、T2、T3与CK2相比,大大增加了花生产量、纯收益,花生秸秆还田后土壤速效氮磷钾含量明显提高;T1处理的纯收益最高,比CK1处理增收花生3720.9 kg hm~(-2),增加纯收益17675.4元hm~(-2),但该处理对花生粗脂肪及甘蔗产量有一定负面影响;T2处理的花生产量、总效益和花生秸秆还田后的土壤速效氮磷钾、有机质含量最高,比CK1处理增收花生4270.8 kg hm~(-2);T3处理比CK1处理增收花生3904.2 kg hm~(-2),花生粗脂肪含量达51.3%,增加纯收益17442.15元hm~(-2),还提高了花生秸秆还田后的土壤速效氮磷钾、有机质含量。综合考虑,甘蔗套种花生(化肥配施半量木薯皮和半量鸡粪)是较好的种植和养分管理模式,值得大面积推广。 相似文献
9.
Crop production in Georgia and the Southeastern U.S. can be limited by water. Highly-weathered, drought-prone soils are susceptible to runoff and erosion. Rainfall patterns generate runoff producing storms followed by extended periods of drought during the crop growing season. Thus, supplemental irrigation is often needed to sustain profitable crop production. Increased water retention and soil conservation would efficiently improve water use and reduce irrigation amounts/costs and sedimentation, and sustain productive farm land, thus improving producer's profit margin. Soil amendments, such as flue gas desulfurization (FGD) gypsum, have been shown to retain rainfall and/or irrigation water through increased infiltration while decreasing runoff (R) and sediment (E). Objectives were to quantify rainfall partitioning and sediment delivery improvements with surface applied FGD gypsum from an Ultisol managed to conventional till (CT) and to assess the feasibility of using FGD gypsum on agricultural land in southern Georgia. A field study (Faceville loamy sand, Typic Kandiudult) was established (2006, 2007) near Dawson, GA managed to CT, irrigated cotton (Gossypium hirsutum L.). FGD gypsum application rates evaluated were 0, 1.1, 2.2, 4.5, and 9 Mg ha− 1. Gypsum treatments and simulated rainfall (50 mm h− 1 for 1 h) were applied to 2-m wide × 3-m long field plots (n = 3). Runoff and E were measured from each 6-m2 plot (slope = 1%). FGD gypsum plots averaged 26% more infiltration (INF), 40% less R, 58% less E, 27% lower maximum R rates (Rmax), and 2 times lower maximum E rates (Emax) than control plots. Values of INF and water for crop use increased, and R, E, Rmax, and Emax decreased as FGD gypsum application rate increased. Values of INF, R, E, Rmax, and Emax for 9 Mg ha− 1 plots were as much as 17% greater, 35% less, 1.9 times less, 35% less, and 1.9 times less than those from other FGD gypsum plots, respectively; and 40% greater, 40% less, 2.2 times less, 52% less, and 2.9 times less than those from control plots, respectively. Applying FGD gypsum to agricultural lands is a cost-effective management practice for producers in Georgia that beneficially impacts natural resource conservation, producer profit margins, and environmental quality. Agriculture in the Southeast provides a viable market for the electric power industry to convert disposal costs of FGD gypsum into a profitable commodity. 相似文献
10.
The ability to map profit across a cotton field would enable producers to determine where money is being made or lost on their farms and to implement precise field management practices to facilitate the highest return possible on each portion of a field. Mapping profit requires knowledge of site-specific costs and revenues, including yield and price. Price varies site-specifically because fiber quality varies, so mapping fiber quality is an important component of profit mapping. To map fiber quality, the harvest location of individual cotton bales must be known, and thus a system to track the harvest location of cotton modules must be available. To this end, a wireless module-tracking system was recently developed, but automation of the system is required before it will find practical use on the farm. In Part 1 of this report, research to develop automatic triggering of wireless messages is described. In Part 2, research to enable the system to function with multiple harvesting machines of the same type in the same field - a common situation in commercial cotton farming - is described along with testing of the entire automated wireless module-tracking system (WMTS). An RFID system was incorporated, and it enabled the WMTS to correctly and consistently differentiate among various harvesting vehicles. The improved WMTS subsequently sent wireless messages to the correct machines when cotton transfers were made in the presence of multiple harvest machines. Overall testing proved that the automated WMTS worked largely as designed. When both complete and partial cotton basket dumps were simulated, the correct wireless-messaging decision was made 100% of the time. 相似文献