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91.
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93.
Water use and water use efficiency of cool season grain legumes in low rainfall Mediterranean-type environments 总被引:1,自引:0,他引:1
K. H. M. Siddique K. L. Regan D. Tennant B. D. Thomson 《European Journal of Agronomy》2001,15(4):267-280
The water use (Et) and water use efficiency (WUE) of a range of cool season grain legume species (field pea [Pisum sativum L.], faba bean [Vicia faba L.], chickpea [Cicer arietinum L.], lentil [Lens culinaris Med.], albus lupin [Lupinus albus L.], dwarf chickling [Lathyrus cicera L.], ochrus chickling [Lathyrus ochrus L.], grass pea [Lathyrus sativus L.], narbon bean [Vicia narbonensis L.], common vetch [Vicia sativa L.], and purple vetch [Vicia benghalensis L.]) were examined on fine textured neutral to alkaline soils in the low to medium rainfall Mediterranean-type environments in south-western Australia at Merredin and Mullewa in two seasons. There was no difference in the total Et between grain legumes at either site in either year. There was also no variation in soil water extraction between species on the shallow sandy loam soil at Merredin. However, C. arietinum, L. sativus and L. cicera had greater water extraction and P. sativum the least water extraction at Mullewa where soil conditions were less hostile and root penetration was not restricted. The pattern of water use varied markedly between the grain legume species examined. Grain yield was positively correlated with post-flowering water use (Etpa) in both erect (r=0.59) and prostrate (r=0.54) grain legume species. Water use efficiencies for dry matter production (WUEdm) of up to 30 kg ha−1 mm−1 for V. faba and V. narbonensis at Merredin, and water use efficiencies for grain yield (WUEgr) of up to 16 kg ha−1 mm−1 for P. sativum and 13 kg ha−1 mm−1 for V. faba at Mullewa, were comparable to those reported for cereals and other grain legumes in previous studies in this and other environments. Potential transpiration efficiencies (TE) of 15 kg ha−1 mm−1 together with soil evaporation (Es) values of 100–125 mm were estimated in this and associated studies, and can be used as benchmark values to assess the yield potential of cool season grain legume crops in low rainfall Mediterranean-type environments. The major traits of adaptation for grain legume species producing large yields in this short season environment are early flowering, and pod and seed set before the onset of terminal drought. Early phenology together with rapid ground cover and dry matter production allows greater water use in the post flowering period. This leads to greater partitioning of dry matter into seed, which is reflected in greater harvest index (HI) and WUEgr, as was observed for V. faba and P. sativum. Improvement in the adaptation of other grain legume species to short season Mediterranean-type environments requires increased early growth for rapid ground cover and improved tolerance to low temperatures (especially for C. arietinum) during flowering and podding. 相似文献
94.
Martin Holmstrup Johannes Overgaard Cino Pertoldi 《Soil biology & biochemistry》2007,39(10):2640-2650
Geographic variation in freeze tolerance, glycogen storage and freeze-induced glucose mobilisation was investigated in the earthworm Dendrobaena octaedra. Specimens from 15 populations collected in Canada, Greenland and Europe were reared in the laboratory in a common-garden experiment to test whether glucose and glycogen concentrations correlated with genetic variation in freeze tolerance among the populations. Populations from Canada, Sweden, Poland and Finland did not differ much in their freeze tolerance and were able to tolerate freezing for 18 d down to at least −14 °C (lowest temperature tested). Specimens collected in a relatively warm climate (Denmark) were the least freeze tolerant, and also had the lowest concentrations of glucose when frozen at −2 °C. However, there was no clear evidence that glucose concentration is a determinant in the degree of freeze tolerance of D. octaedra when considering the whole assemblage of populations. The role of phylogenetic inertia was tested by looking for serial independence and no influence of phylogeny was detected in our findings allowing us to exclude the possibility that phylogenetic relatedness between populations is a major evolutionary factor explaining the observed differences for freeze tolerance and related traits. The size of the glycogen reserve was significantly correlated with the ability to tolerate freezing. Large glycogen reserves may be advantageous in very cold regions in order to maximise cryoprotectant production and/or as a source of energy for the anaerobic metabolism occurring during prolonged freezing. 相似文献
95.
Anna Ro?en 《Soil biology & biochemistry》2006,38(3):489-503
This study examined whether earthworm (Dendrobaena octaedra) populations originating from three differently polluted mixed oak-pine forests differ in life history parameters, and whether any observed differences are adaptive. Three forests were chosen: the most polluted forest, near Olkusz, affected by a zinc smelter and on soil containing metal ore; the Niepo?omice Forest, moderately polluted by industry; and the relatively unpolluted Kampinoska Forest. Parent animals (P generation) were collected from each forest and thereafter cultured in the laboratory. From cocoons laid in the laboratory the F1 generation was reared and observed to determine whether it inherited features observed in the parent generation. To distinguish the effect of the metal studied (Cd) from that of soil edaphic conditions, individuals collected in the field were divided into two groups: one cultured in unpolluted medium, the other in medium spiked with cadmium. Earthworms originating from polluted forests (parent generation) exhibited higher cadmium storage capacity, and a higher cadmium concentration factor (cadmium in animal/cadmium in soil). No interpopulation differences in cadmium accumulation were found in their offspring (F1 generation), meaning that the cadmium accumulation ability was acclimatory and not adaptive. Cadmium in low doses negatively affected reproduction parameters: cocoon production, mass of produced cocoons, and reproductive allocation (weight of offspring divided by the weight of adults). The effect of cadmium was stronger in animals originating from the unpolluted forest than in those from the heavily polluted forest. F1 animals originating from the heavily polluted forest exhibited the highest cadmium tolerance (higher mean survival time and median survival time, lower hazard rate probability per time unit that an individual surviving to the beginning of a given interval will die within that interval). The observed tolerance to cadmium (higher reproduction, better survival) in the population from the heavily polluted forest apparently was heritable, suggesting adaptation of D. octaedra to life in a polluted environment. 相似文献
96.
Stuart G. Field 《Soil biology & biochemistry》2006,38(6):1334-1339
The earthworm Lumbricus terrestris has relatively low dispersal rates. This can represent a challenge for the internal gregarine parasite Monocystis, the dispersal of which often depends on the host. Mating of Monocystis can also be restricted to parasite stages within the current host individual. Adaptations, including host behavioural modification, that improve parasite transmission and simultaneously avoid inbreeding within a single host individual should be favoured by selection. We used a correlative approach to investigate the question of parasitic manipulation in this Gregarine-Lumbricid system. We observed mature earthworms (n=24) for 3 weeks while recording various measures of activity (surface activity, burrowing activity, surfacing delay, number of surface visits) and correlated parasite load with these activity measures. We found a significant positive correlation between surface activity and midden (or cast) production, which suggests a simple method for assessing the overall activity of local earthworm populations. However, we found no evidence of behavioural manipulation of any measure of host activity. We discuss these results in the context of inbreeding depression and host-parasite coevolution. 相似文献
97.
Changes in rice phenology during 1981–2009 were investigated using observed phenological data from hundreds of agro-meteorological stations across China. Spatiotemporal changes of rice phenology across China, as well as the relations to temperature, day length and cultivars shifts were analyzed and presented. We found that major rice phenological dates generally advanced while rice growing period changed diversely for different rice cultivation systems in different agro-ecological zones. Length of vegetative growth period (VGP) increased at 59 (67.0%) stations for single-rice, however, decreased at 36 (54.5%) and 35 (51.5%) stations for early-rice, and late-rice, respectively. Length of reproductive growth period (RGP) increased at 71 (70.3%) and 49 (55.7%) stations for single-rice and early-rice, respectively, however, decreased at 46 (54.8%) stations for late-rice. The changes were ascribed to the combined effects of changes in temperature, photoperiod and cultivar thermal characteristics. Increase in temperature had negative impacts on the lengths of VGP and RGP. Day length slightly counterbalanced the roles of temperature in affecting the duration of VGP. Furthermore, we found that during 1981–2009 cultivars with longer growth duration of VGP were adopted for single-rice, but cultivars with shorter growth duration of VGP were adopted for early-rice and late-rice. Cultivars with longer growth durations of RGP were adopted for single-rice and early-rice, as well as late-rice at the middle and lower reaches of Yangtze River. However, in the southwestern China and southern China, cultivars with shorter or almost same growth duration of RGP were adopted for late rice. 相似文献
98.
国家重点保护植物绵刺的适应性及其保护的研究 总被引:11,自引:0,他引:11
绵刺是蒙古高原特有的单种属植物,已列为国家二级重点保护植物。本文系统地综述了绵刺的生态生物学特性,并探讨了其适应性,研究结果表明,绵刺具有典型旱生植物的结构和特征,耐旱、耐贫瘠、耐盐碱和抗风蚀能力较强,对恶劣的环境条件具有良好的适应性。文章还分析了绵刺濒危的可能原因,并提出了保护措施。 相似文献
99.
羊茅属8种牧草在"黑土型"退化草地上的适应性表现 总被引:4,自引:0,他引:4
在青海省达日县和玛沁县“黑土型”退化草地上引种的羊茅属8种牧草中有4个可安全越冬,抗寒性强,适应性随栽培年限延长而提高。其中,中华羊茅第2年开始生长发育即达完整,第2、第3年单位面积草产量接近1000g/m^2,种子产量高。下繁草毛稃羊茅、西北羊茅和紫羊茅(同德)第2年生殖枝占20%~35%,生殖生长不整齐,第3年开始产量大幅度增加,适应性增强。越冬良好的4种牧草对“黑土型”退化草地的适应性较强。 相似文献
100.
Palm oil production has increased in recent decades and is estimated to increase further globally. The optimal role of palm oil production, however, is controversial because of conflicts with other important land uses and ecosystem services. Local conditions and climate change affect resource competition and the desirability of palm oil production in the Niger Delta, Nigeria.The objectives of this study are to (1) establish a better understanding of the existing yield potentials of oil palm areas that could be used for integrated assessment models, (2) quantify for the first time uncertainties in yield potentials arising from the use of climate output data from different Global Circulation Models (GCM’s) with varied West African Monsoon (WAM) system representations forced to the same Regional Climate Models (RCM’s). We use the biophysical simulation model APSIM (Agricultural Production Systems Simulator) to simulate spatially variable impacts of climate change on oil palm yield over the Nigerian Niger Delta. Our results show that the impact of climate change on oil palm yield is considerable across our study region. The yield differences between the IPCC RCPs were small. The net impact of climate change on oil palm is positive and is dynamically inconsistent. There is no significant change in the simulated yield arising from the differences in the forcing’s data. We found the most effective strategy for oil palm yield optimization under climate change to be shifting of sowing dates and introduction of irrigation. 相似文献