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871.
Socio-economic significance of reed forests in a rural community: A case study from the greater Sylhet Region of Bangladesh 总被引:1,自引:0,他引:1
Qumruzzaman Chowdhury A. Z. M. Manzoor Rashid Masuduzzaman Afrad 《Small-Scale Forestry》2004,3(1):121-130
The reed forests that are the subject of this study are scattered over five thanas of the Sunamganj and Sylhet Districts of
the Sylhet Division of Bangladesh. Their total area is 23,590 ha and they have great ecological, economic, commercial and
socio-economic importance due to the diversified resources they supply. However, the forests are commonly encroached on by
local people who are perceived to be seriously depleting the resource. This paper deals with the socio-economic status of
the people residing near these reed forests, and examines their dependency on the resources provided by the reed forests.
A socio-economic survey, participatory rural appraisal and interviews were used to obtain baseline data of the reed forest
resource and the local communities. The study reveals that the communities in the study region have higher income than other
areas of Bangladesh. Most survey respondents have other occupations in addition to farming. The literacy rate is 28.8%. Among
the illiterate, 68% engage in collecting reeds. Although the Forest Department has a management plan for sustainable use of
the reed forests, encroachers receive backing from political leaders and local elites, so their eviction is difficult. In
order to achieve long-term productivity and sustainability from the reed forests, this study recommends a strategy of developing
an integrated joint management plan between the Forest Department and the local people. 相似文献
872.
Ian Jeffreys 《Small-Scale Forestry》2004,3(1):99-117
Small-scale farm forestry has the potential to offer many benefits both to landholders and the wider community. As with all
changes in land-use practices, there are associated benefits and costs and these are not uniformly distributed. They have
varying impacts on the different values, aspirations, goals and objectives that exist within the community. Furthermore, the
community does not consider these values, aspirations, goals and objectives of equal importance. The degree of concern can
vary from minor to high and overriding all other considerations. When evaluating farm forestry options it is necessary to
address all of these concerns. This paper examines the combined use compensatory and non-compensatory multi-criteria analyses
to evaluate forestry options, in a case study for the Darling Downs region of Queensland, Australia. These aggregation techniques
are found to be highly complementary and together provide a comprehensive analysis. The compensatory technique provides a
sound measure of overall performance of a forestry system, whereas the non-compensatory technique alerts decision-makers to
presence of particularly poor performance with respect to individual criteria. The compensatory technique used is simple and
understandable even for those with non-mathematical backgrounds. This analysis can identify and aid communication of the relative
benefits and costs, and trade-offs, between economic, environmental and social considerations. 相似文献
873.
This study was carried out to investigate the possibility of calibrating a prediction model for the moisture content and density distribution of Scots pine (Pinus sylvestris) using microwave sensors. The material was initially of green moisture content and was thereafter dried in several steps to zero moisture content. At each step, all the pieces were weighed, scanned with a microwave sensor (Satimo 9,4GHz), and computed tomography (CT)-scanned with a medical CT scanner (Siemens Somatom AR.T.). The output variables from the microwave sensor were used as predictors, and CT images that correlated with known moisture content were used as response variables. Multivariate models to predict average moisture content and density were calibrated using the partial least squares (PLS) regression. The models for average moisture content and density were applied at the pixel level, and the distribution was visualized. The results show that it is possible to predict both moisture content distribution and density distribution with high accuracy using microwave sensors. 相似文献
874.
对采自15个省区的55个枫杨种源种子在浙江安吉进行苗期试验。参试种源表现出明显的苗期生长差异,苗高的极差达163%,地径极差达180%,生物量极差达194%。种源苗高生长表现出明显的南-北纬向及垂直变异趋势,枫杨南部分布区及低海拔种源的高生长一般优于北部分布区和高海拔地区的种源。枫杨在长江中下游亚区、江南丘陵及华南亚区、漓江-湘江-洞庭湖水系、贵川陕西部亚区、北部亚区内表现出各自的亚区变异模式。根据苗高、地径及总生物量等主要性状,构建综合选择指数函数I=0.1167X1(总干质量/g) 0.0750X2(苗高/cm)-0.1231X3(地径/cm),并评选出6个苗期生长优良的种源,即江西南部的信丰,贵州东北部的思南,陕西中部的汉中,湖南洞庭湖的益阳,重庆的涪陵以及福建东北部的福安种源。 相似文献
875.
876.
Catia Pereira Itziar Aurora Montalbán Olatz García-Mendiguren Tomás Goicoa Maria Dolores Ugarte Sandra Correia Jorge Manuel Canhoto Paloma Moncaleán 《Journal of Forest Research》2016,21(3):143-150
Pinus halepensis has been described as a drought-tolerant species with high plasticity to growth in different environments. Its eco-physiological characteristics could facilitate the use of this species in large afforestations in the future scenery of climate change. Somatic embryogenesis is a biotechnological tool with potential for large-scale clonal propagation. In order to establish an improved regeneration protocol for Pinus halepensis, the effects of different temperatures (18, 23, and 28 °C) and water availability conditions (2, 3, and 4 g L?1 Gelrite®), during initiation of embryonal masses on the rate of initiation, proliferation, maturation, and the number of embryos developed, were evaluated. It was found that environmental conditions during the initiation stage of Pinus halepensis somatic embryogenesis influence the success of initiation and proliferation. In contrast, there was no effect of these conditions on the maturation rates and the number of somatic embryos. Somatic embryos were obtained in all treatments tested, indicating that plants can be produced from extreme conditions of induction, such as high temperatures (28 °C) and low water availability conditions (4 g L?1). 相似文献
877.
Rui Fang Wang Feng Lan Huang Jian Zhang Qiu Yan Zhang Li Na Sun Xing Shun Song 《Journal of Forest Research》2016,21(5):244-250
Cerasus humilis is a species of small, perennial, drought-resistant and multipurpose deciduous shrub grown in arid and semi-arid conditions in northern China. In this study, an efficient protocol for the rapid micropropagation of C. humilis has been standardized using stem and/or leaf explants. Direct multiple shoot induction was observed when the stem explants were cultured on Murashige and Skoog (MS) medium supplemented with different plant growth regulators. The highest shoot induction was obtained when stem explants from adult trees were cultured on MS medium supplemented with 2.0 mg L?1 6-benzyladenine (6-BA) and 0.9 mg L?1 α-naphthaleneacetic acid (NAA). The leaf and stem explants cultured on MS medium with 1.0 mg L?1 6-BA and 0.6 mg L?1 NAA, and 0.5 mg L?1 6-BA and 0.8 mg L?1 NAA, respectively, produced the highest induction frequency of callus. Maximum proliferation of callus was observed on MS medium containing a combination of 0.5 mg L?1 6-BA with 0.6 mg L?1 2,4-dichlorophenoxyacetic acid (2,4-d). Optimal shoots differentiated from callus were obtained on MS medium supplemented with 5.0mg L?1 6-BA and 0.9 mg L?1 NAA. In vitro rooting was achieved on half-strength (1/2) MS medium containing 0.5 mg L?1 NAA. Rooted plantlets were hardened under control conditions and successfully acclimatized under field conditions. 相似文献
878.
Mohamed Z. M. Salem Mohamed Z. Zayed Hayssam M. Ali Mamoun S. M. Abd El-Kareem 《Journal of Wood Science》2016,62(6):548-561
In the present work, for the first time, the chemical components of essential oils (EOs) and extracts from wood branch (WB) resulted from the tree pruning wastes of Schinus molle L. grown in Egypt were evaluated for their antioxidant and antibacterial activities. EOs, methanol (ME), dichloromethane (DCME) and water (WE) extracts as antioxidant and antibacterial activities were measured. Total phenolic and flavonoid contents as well as analysis of extracts by gas chromatography–mass spectrometry (GC–MS) were reported. The major components in EOs were α-elemol, β-pinene, and α-phellandrene, in ME were 6-(4-chlorophenyl)-3-cyano-4-(N-benzylpiperazino)-2H-pyran-2-one, and 2-naphthalene methanol, decahydro-α,α,4a-trimethyl-8-methylene, in DCME were 12-methyl-E,E-3,13-octadecadien-1-ol, and 1,2-benzenedicarboxylic acid, dioctyl ester, and in WE were β-eudesmol, and (Z,Z,Z)-9,12,15-octadecatrienoic acid, 2,3-dihydroxypropyl ester. The highest total antioxidant activity was found with EOs (90 ± 1.23 %) and WE (86.30 ± 1.40 %). The lowest IC50 values of 13.11 ± 3.00, and 12.66 ± 2.15 μg/mL were found with WE and EOs, respectively. EOs and WE were observed to have good antibacterial activity against Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Escherichia coli, Sarcina lutea, Pseudomonas aeruginosa, and Micrococcus luteus. In conclusion, the Schinus molle L. WB EOs and extracts might, indeed, be used as a potential source for pharmaceutical or food industries. 相似文献
879.
Stefan Fleck Nathalie Cools Bruno De Vos Henning Meesenburg Richard Fischer 《Annals of Forest Science》2016,73(4):945-957
Key message
Aggregated, consolidated, and derived soil physicochemical data of 286 ICP Forests Level II plots were completed with soil hydraulic properties for integrated use with forest monitoring data. Database access should be requested at http://icp-forests.net . Metadata associated available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/?uuid=153e599e-6624-4e2b-b862-8124386ea9cd&hl=engContext
The ICP Forests database is one of the most comprehensive forest ecosystem datasets in Europe and contains the accumulated results of more than two decades of harmonised forest monitoring all over Europe.Aims
The aim of this paper is to share knowledge on the ICP Forests Level II soil data for broader use among forest scientists.Methods
After standard analysis, quality checks, aggregation, and calculation of derived variables (e.g. nutrient stocks, base saturation, C:N ratio, and water retention parameters), data have been gathered into a static database (AFSCDB.LII.2.2), which will be updated to new versions as soon as new measurements become available.Results
The database provides a basis for the combined evaluation of up to 130 unique soil variables of 286 plots with dynamic data on tree growth, ground vegetation, foliar chemistry, crown condition, tree phenology, leaf area index, ozone injury, litterfall, soil solution chemistry, deposition, ambient air quality, and meteorological data assessed on the same plots.Conclusion
The unprecedented comprehensiveness and level of detail in this newly aggregated database may overcome existing restrictions so far impeding the realisation of large-scale forest ecosystem studies in Europe.880.
One way of meeting the supply demands of the wood industry is through the reduction of waste in timber processing. It has
been estimated in Ghana that for every tree felled, nearly 50% of the tree volume is left in the forest in the form of branches,
crownwood, and stumps. In this study, the potential of utilizing branchwood as raw material from logging residues to help
meet the timber demands of the downstream processing sector was analyzed experimentally. The sawing characteristics of the
branchwood of Aningeria robusta and Terminalia ivorensis with diameters in the range 10–25 cm using live sawing and cant sawing methods were determined using a randomized complete
block design, 2 × 4 factorial with three replications. Experimental results indicate that, the relative lumber value yields
for first and second grade boards of A. robusta and T. ivorensis branches were 25 and 20%, respectively, while the green lumber volume yields were 40 and 32%, respectively. A high proportion
of sapwood and the occurrence of washboarding in T. ivorensis contributed to that species’ relatively low lumber value and volume yield. The experimental results further indicate that
the sawing technique used had no significant influence on lumber yields. However, at 5% level of significance, significant
differences in lumber yield existed between some of the diameter classes. 相似文献