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881.
Zusammenfassung Im Juni 1986 wurde im Irak eine Sammelreise durchgeführt. Landsorten von Getreide, Gemüsen und einigen anderen Kulturpflanzen konnten gesammelt werden; insgesamt 141 Proben. Die Generosion ist bei den Getreiden schon weit fortgeschritten. Durch die Einführung vieler neuer Gemüsesorten muß in den nächsten Jahren mit einem empfindlichen Verlust von Gemüse-Landsorten gerechnet werden. Das Sammelmaterial ist von großer Bedeutung für die Züchtungsforschung und Züchtung.
Collection of land-races of cultivated plants in Iraq, 1986
Summary A collecting mission was carried out in Iraq in June 1986. Land-races of cereals, vegetables and some other crops could be collected, altogether 141 accessions. Genetic erosion is advanced in cereals. Because of the introduction of many new cultivars a severe loss of vegetable land-races has to be expected in the next years. The material collected is important for breeding research and breeding purposes.

1986
1986 , , . 141 . ¶rt;. - , , , . , .
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882.
883.
Soil quality deterioration and consequent reduced productivity characterize the Vertisols in the highlands of Ethiopia. The problem is exacerbated by lack of appropriate land preparation alternatives for the major crops in the area. A field experiment was carried out for 6 years (1998–2003) at Caffee Doonsa in the central highlands of Ethiopia to evaluate alternative land preparation methods on the performance of wheat (Triticum durum Desf.), lentil (Lens culinaries Medik L) and tef (Eragrostis tef L) grown in rotation. Four methods of land preparation (broad bed and furrow, green manure, ridge and furrow and reduced tillage) were arranged in a randomized complete block design with three replications on permanent plots of 22 m by 6 m. Broad bed and furrow significantly increased the grain yield of lentils by 59% (from 1029 to 1632 kg ha−1) as compared to the control. On the other hand, reduced tillage resulted in the highest grain yield of wheat (1862 kg ha−1) and tef (1378 kg ha−1) as compared to 1698 kg ha−1 of wheat and 1274 kg ha−1 of tef for the control although the increase was not statistically significant. A gross margin analysis showed that BBF is the most profitable option for lentil with 65% increase in total gross margin. On the other hand, RT resulted in 11 and 8% increase in gross margin of wheat and tef, respectively as compared to the control. Based on the agronomic and economic performances best combinations of crop and land preparation method were: lentil sown on broad bed and furrow, and wheat and tef sown after reduced tillage.  相似文献   
884.
Anthocyanins are responsible for a variety of bright colors including red, blue, and purple in fruits, vegetables, and flowers and are consumed as dietary polyphenols. Anthocyanin-containing fruits are implicated in a decrease in coronary heart disease and are used in antidiabetic preparations. In the present study, we have determined the ability of anthocyanins, cyanidin-3-glucoside (1), delphinidin-3-glucoside (2), cyanidin-3-galactoside (3), and pelargonidin-3-galactoside (4), and anthocyanidins, cyanidin (5), delphinidin (6), pelargonidin (7), malvidin (8), and petunidin (9), to stimulate insulin secretion from rodent pancreatic beta-cells (INS-1 832/13) in vitro. The compounds were tested in the presence of 4 and 10 mM glucose concentrations. Our results indicated that 1 and 2 were the most effective insulin secretagogues among the anthocyanins and anthocyanidins tested at 4 and 10 mM glucose concentrations. Pelargonidin-3-galactoside is one of the major anthocyanins, and its aglycone, pelargonidin, caused a 1.4-fold increase in insulin secretion at 4 mM glucose concentration. The rest of the anthocyanins and anthocyanidins tested in our assay had only marginal effects on insulin at 4 and 10 mM glucose concentrations.  相似文献   
885.
Background   Aims, and Scope. Reducing heavy metal solubility and bioavailability in contaminated area without removing them from the soil is one of the common practices in decreasing the negative impacts on the environment and improving the soil quality. Therefore, our aim was to study the effect of clay minerals: Na-bentonite, Ca-bentonite, and zeolite applied to a contaminated soil on immobilization of heavy metals, as well as on some soil parameters related with microbial activity. Methods   A soil derived from sewage sludge was incubated with clay minerals of either Na-bentonite, Ca-bentonite, or zeolite for 111 days (d). During the incubation experiment, concentrations of water soluble Zn, Cd, Cu, and Ni were measured after extraction of 2 g air-dry soil with 50 ml of H2O for 2 h. After the water extraction, the soil sediment was extracted with 50 ml of 1 M NH4NO3 for 2 h to estimate the exchangeable amounts of heavy metals. Furthermore, soil microbial respiration, microbial biomass C, Corg mineralization, metabolic quotient (qCO2), and inorganic N were also investigated. Results and Discussion   Water extractable and exchangeable forms of heavy metals were changed by incubation and addition of clay minerals. Incubation of soil without addition of clay minerals (control) increased water extractable Cu by 12, 24 and 3.8% of initial content after 21, 62, and 111 d of incubation, respectively. The water extractable Zn decreased by 9% during 62 d of incubation and it tended to increase by 14% at the end of the incubation, as compared with the initial soil. Water extractable Cd decreased by 71, 66 and 33% of initial content, and Ni decreased by 54, 70, and 58%, after 21, 62, and 111 d of incubation, respectively. During the incubation experiment, the exchangeable form of all tested metals was decreased by incubation. The addition of clay minerals led to a significant decrease in water soluble and exchangeable forms of heavy metals during the incubation experiment, resulting in low metal extractability. The reduction in metal extractability was greater due to the addition of Na-bentonite or Ca-bentonite than that due to the addition of zeolite. During the first 3 weeks after addition of clay minerals, the studied biological parameters were not affected. However, as incubation progressed, the addition of Na- or Ca- bentonite led to a significant increase in soil respiration, microbial biomass C, Corg mineralization, and inorganic N; and a significant decrease in qCO2. This result is explained by sorption of heavy metals on Na-bentonite and Ca-bentonite and strong reduction of their toxicity. Conclusions   Our results clearly show that the addition of clay minerals, especially of Na-bentonite and Ca-bentonite, decreased the extractability of four metals during incubation. The decreased metal extractability was accompanied by an increase of soil respiration, Corg mineralization, microbial biomass C, and inorganic N and a decrease of metabolic quotient (qCO2), showing positive effect of clay mineral addition on soil biological parameters. Recommendations and Outlook   The use of Na-bentonite and Ca-bentonite is promising tool for reduction the extractability and possible toxicity of heavy metals in sewage sludge-contaminated soil. Therefore, the soils polluted with heavy metals may be ameliorated by addition of clay minerals, especially Na-bentonite and Ca-bentonite.  相似文献   
886.
Although the large variations in nitrate export from forested watersheds have been attributed to a variety of natural and disturbance-related factors, baseflow nitrate concentrations in 49 mid-Appalachian forested watersheds were most strongly related to differences in bedrock geology. Within the mid-Appalachian region of Pennsylvania, Maryland and West Virginia, watersheds dominated by Pottsville and Allegheny sandstone (PVA), Catskill, Chemung, and Pocono shale and sandstone (CCP), and Mauch Chunk shale and Greenbrier limestone (MCG), respectively, exhibited significantly different low, intermediate, and high mean stream nitrate concentrations. Soil pH, soil percent N concentration (%N), soil C:N mass ratio, soil exchangeable Ca, watershed slope, and the occurrence of white ash (Fraxinus americana L.), sugar maple (Acer saccharum Marsh.), and eastern hemlock (Tsuga canadensis L.) were related significantly to bedrock geology type as well as stream nitrate levels. Other factors such as past land disturbances (fire and agriculture) and stand age (old-growth) typically were associated with only one bedrock geology type. However, within a bedrock geology type, past agriculture and the presence of old-growth forest may be important in explaining stream nitrate concentrations on an individual watershed basis. The basal area of black locust (Robinia pseudoacacia L.), a species that enhances soil nitrogen levels via nitrogen fixation, showed a moderate positive correlation with stream nitrate concentrations. Bedrock geology explained the most variation in winter (49%) and summer (32%) stream nitrate concentrations. Bedrock geology may have been a better predictor of stream nitrate concentrations than soil chemistry, because the geologic variation was better assessed at the regional scale of this study compared to soil chemistry, which varies at the micro-scale due to topographic, vegetation, microbial, and climatic influences. Results of this study suggest that bedrock geology is an important factor to consider when assessing forest nitrogen dynamics at a broad landscape scale.  相似文献   
887.
Summary Important papers on taxonomy and evolution of cultivated plants published in 1979 and 1980 were put together and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1979/1980
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1979 und 1980 wurden zusammengestellt und kurz kommentiert.

: 1979–1980
, 1979–1980 . .
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888.
Das Domestikationssyndrom   总被引:1,自引:1,他引:1  
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889.
Summary A collecting mission was carried out in the Democratic People's Republic of Korea jointly by staff members of the Institute for Experimental Biology, Pyongyang, and the Zentralinstitut für Genetik und Kulturpflanzenforschung, Gatersleben, in November 1985 for studying and collecting indigenous forms of cultivated plants. 127 samples, mainly of grain legumes, vegetables and medicinal plants were collected. The material represents highly variable old land-races; this is especially true for french beans, soya beans, other grain legumes and some vegetables. Genetic erosion is rather advanced for maize, rice, wheat, radish and the brassicas. Genetic resources of these crops can be expected in more marginal areas. The results of the mission stress the necessity for continuing the explorations.
Anmerkungen zu einer Exploration von Kulturpflanzen-Landsorten in der Koreanischen Demokratischen Volksrepublik im Jahre 1985
Zusammenfassung Eine Reise wurde im November 1985 in der Koreanischen Demokratischen Volksrepublik gemeinsam von Mitarbeitern des Instituts für Experimentelle Biologie, Pyongyang, und des Zentralinstituts für Genetik und Kulturpflanzenforschung, Gatersleben, unternommen, die dem Studium und der Sammlung indigener Formen von Kulturpflanzen diente. 127 Proben, besonders von Körnerleguminosen, Gemüsen und Arzneipflanzen, wurden gesammelt. Das Material besteht aus hochvariablen alten Landsorten, besonders von Gartenbohnen, Sojabohnen, anderen Körnerleguminosen und einigen Gemüsen. Die Generosion ist bei Mais, Reis, Weizen, Rettich und denBrassica-Arten schon weit fortgeschritten. Genetische Ressourcen dieser Arten können in den abgelegeneren Landesteilen erwartet werden. Die Ergebnisse der Sammelreise unterstreichen die Notwendigkeit weiterer Explorationen.

- 1985
1985 () () - . 127 , , . , , , . , , Brassica , , ë . .
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890.
Soil erosion, along with the contributing factors of soil crusting and sealing, have received minimal scientific attention to date in Latin America. This study was conducted in an Andean hillside environment to determine how the local organic manuring and tillage practices influence the development of soil crusting and sealing, and the extent to which these practices influence soil water infiltration. The aim of this study was to identify treatments that prevented superficial soil structural constraints, i.e. treatments which maintain infiltration and therefore reduce potential soil erosion and run-off.

Treatment results were measured with a pocket penetrometer and a mini-rain simulator on nine different cropping systems, mainly based on cassava (Manihot esculenta Crantz), from February to November 2000 and 2001. The cropping systems were laid out on a Ferrallic Cambisol, an acid, vulcanically influenced soil of the Andean region.

In both cropping cycles, treatments with chicken manure application developed superficial soil crusts during the dry season. For a treatment manured with 8 t ha−1 chicken manure, this crust meant an increase in penetration resistance from 2.3 kg cm−2 in April 2000 to 16.2 kg cm−2 in July 2000. The change in superficial soil structure created a notable reduction in final infiltration from 92 to 42.2 mm h−1. A minimum tillage treatment which displayed the highest penetration resistance during the dry periods of up to 46.4 kg cm−2 presented no restricting effects on soil water intake (76.2 mm h−1 final infiltration in 2000) due to an optimal aggregate development during 10 years of consecutive conservation practice.

Measurements of penetration resistance and infiltration showed that soil conserving treatments, such as minimum tillage and crop rotations, improved the physical soil status and prevented soil crusting developing along with its negative effects on infiltration. These methods can therefore be strongly recommended to farmers.  相似文献   

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