引诱剂在红脂大小蠹防治中的应用

2005年5-6月,在山西省屯兰川林场开展了不同配方高效引诱剂防治红脂大小蠹Dendroc-tonus valens LeConte试验,结果显示:β-蒎烯:α-蒎烯:3-蒈烯1:1:3或全部是3-蒈烯的两种配方为最佳配方,平均费用82.5元/hm2.2006年5-6月,使用β-蒎烯:α-蒎烯:3-蒈烯为1:1:1配方的引诱剂对红脂大小蠹进行了防治,林木被害率下降64.5%,平均侵入孔数下降58.9%.     

Behavior of Natural Estrogens in Reservoir: Investigations Based on Continuous Flow Experiments and Model Analysis

The behavior of estrone (E1) and 17??-estradiol (E2) in relatively closed water environment was studied by continuous flow experiment using sediments from a freshwater reservoir. For this, four sediment columns (two oxic ones and two anoxic ones) were employed, which were structured by packing 30?cm of undisturbed sediment and 60?cm of overlying water collected from two sites within a reservoir. A mass balance model that considered the influent flux, the effluent flux, mass transfer, sorption, and biodegradation was proposed to describe the behavior of E2 and E1 in the columns. The results indicated that the water?Csediment partition coefficient of E1 $ \left( {K_{\text{d}}^{\text{E1}}} \right) $ was higher than E2 $ \left( {K_{\text{d}}^{\text{E2}}} \right) $ . The degradation rate of E1 (k _E1) was smaller than E2 (k _E2). Under both oxic and anoxic conditions, E1 was formed from E2. Furthermore, to clarify the impact of the model parameters such as the hydraulic retention time (HRT), K _d, and k on the behavior of E2 and E1, variance analysis was performed based on the results of model simulations. The results showed that the concentrations of E2 and E1 in the column effluent were controlled most significantly by the sorption capacity of the natural estrogens onto sediment particles, with the determined contributory ratios changing in the order of sorption > HRT > degradation.     

Risk-based surveillance for avian influenza control along poultry market chains in South China: The value of social network analysis

Over the past two decades, the poultry sector in China went through a phase of tremendous growth as well as rapid intensification and concentration. Highly pathogenic avian influenza virus (HPAIV) subtype H5N1 was first detected in 1996 in Guangdong province, South China and started spreading throughout Asia in early 2004. Since then, control of the disease in China has relied heavily on wide-scale preventive vaccination combined with movement control, quarantine and stamping out. This strategy has been successful in drastically reducing the number of outbreaks during the past 5years. However, HPAIV H5N1 is still circulating and is regularly isolated in traditional live bird markets (LBMs) where viral infection can persist, which represent a public health hazard for people visiting them. The use of social network analysis in combination with epidemiological surveillance in South China has identified areas where the success of current strategies for HPAI control in the poultry production sector may benefit from better knowledge of poultry trading patterns and the LBM network configuration as well as their capacity for maintaining HPAIV H5N1 infection. We produced a set of LBM network maps and estimated the associated risk of HPAIV H5N1 within LBMs and along poultry market chains, providing new insights into how live poultry trade and infection are intertwined. More specifically, our study provides evidence that several biosecurity factors such as daily cage cleaning, daily cage disinfection or manure processing contribute to a reduction in HPAIV H5N1 presence in LBMs. Of significant importance is that the results of our study also show the association between social network indicators and the presence of HPAIV H5N1 in specific network configurations such as the one represented by the counties of origin of the birds traded in LBMs. This new information could be used to develop more targeted and effective control interventions.     

试论农业规模经营与农业增长的关系

详细分析了农业规模经营与土地生产率、劳动生产率、农产品成本及农产品有效供给的关系，认为农业生产经营单位土地经营规模的适度扩大将有力地促进农业增长。     

谈农业科技推广体制的调整战略

在分析我国农业科技推广体制运行背景及现状的基础上，提出调整我国农业科技推广体制的目标是建立市场机制与行政协调相结合的新模式     

水稻抗旱节水栽培技术

针对水田面临严重缺水局面,为了缓解水田旱情,从选用耐旱品种、培育壮秧、免耕轻耙、间断灌水等栽培技术入手,介绍了水稻抗旱节水栽培技术的关键环节。提出了耐旱高产品种、培育壮秧、旱整地、重施底肥、全层施氮、根据水稻不同生育期间断灌溉等具体节水措施。     

Water use efficiency and fruit quality of table grape under alternate partial root-zone drip irrigation

Two-year field experiments were conducted to investigate the effect of alternate partial root-zone drip irrigation on fruit yield, fruit quality and water use efficiency of table grape (Vitis vinifera L. cv Rizamat) in the arid region of northwest China. Three irrigation treatments were included, i.e. CDI (conventional drip irrigation, both sides of the root-zone irrigated), ADI (alternate drip irrigation, both sides of the root-zone irrigated alternatively with half the water) and FDI (fixed drip irrigation, only one side of the root system irrigated with half the water). Results indicated that compared to CDI, ADI kept the same photosynthetic rate (P_n) but reduced transpiration rate, thus increased leaf water use efficiency (WUE) of table grape. And diurnal variation of leaf water potential showed no significant differences during 7.00 a.m. to 14.00 p.m. in both years. ADI also produced similar yield and improved WUE_ET by 26.7–46.4% and increased the percentage of edible grape by 3.88–5.78%, vitamin C content in the fruit by 15.3–42.2% and ratio of total soluble solid concentration/titrated acid in both years as compared to CDI. Thus ADI saved irrigation water, improved the water use efficiency and fruit quality of table grape without detrimental effect on the fruit yield in arid region.     

Comparison of dynamic and static APRI-models to simulate soil water dynamics in a vineyard over the growing season under alternate partial root-zone drip irrigation

In this paper, a two-dimensional (2D) dynamic model of root water uptake was proposed based on soil water dynamic and root dynamic distribution of grapevine, and a function of soil evaporation related to soil water content was defined under alternate partial root-zone drip irrigation (APDI). Then the soil water dynamic model of APDI (dynamic APRI-model) was developed on the basis of the 2D dynamic model of root water uptake and soil evaporation function over the growing season. Soil water dynamic in APDI was respectively simulated by dynamic and static APRI-models. The simulated soil water contents by two models were compared with the measured value. Results showed that values of root-mean-square-error (RMSE) for dynamic APRI-model were less than that of the static APRI-model either in the east side or the west side of grapevine. The average relative error between the simulated and measured value was less than 5% for dynamic APRI-model, indicating that the dynamic APRI-model is better than the static APRI-model in simulating the soil moisture dynamic throughout the growing season under the APDI.     

福建省花卉业的现状与发展对策

笔者对福建省花卉业进行深入的调研,分析现状,找出存在的问题,提出今后的发展的对策,以其为发展福建省花卉业提供一些依据。调研表明：福建省花卉业良性发展,形成了优势区域布局,产品日趋多样化,育苗技术初步应用,销售渠道基本畅通。但也存在竞争力不强、抵御自然灾害能力弱、科技含量不高、市场信息与服务体系融合不恰及优惠政策力度不够等问题。笔者认为发展福建省花卉业应进一步优化产业结构,走产业化道路,要制定优惠政策,健全政策法规和标准,进一步拓宽销售渠道,实施科教兴花战略,拓展闽台花卉合作交流,提升花卉产业层次     

Relationship between stable carbon isotope discrimination and water use efficiency under regulated deficit irrigation of pear-jujube tree

To investigate the relationship between stable carbon isotope discrimination (Δ) of different organs and water use efficiency (WUE) under different water deficit levels, severe, moderate and low water deficit levels were treated at bud burst to leafing, flowering to fruit set, fruit growth and fruit maturation stages of field grown pear-jujube tree, and leaf stable carbon isotope discrimination (Δ_L) at different growth stages and fruit stable carbon isotope discrimination (Δ_F) at fruit maturation stage were measured. The results indicated that water deficit had significant effect on Δ_L at different growth stages and Δ_F at fruit maturation stage. As compared with full irrigation, the average Δ_L at different growth stages and Δ_F at fruit maturation stage were decreased by 1.23% and 2.67% for different water deficit levels, respectively. Δ_L and Δ_F among different water deficit treatments had significant difference at the same growth stage (P < 0.05). Under different water deficit conditions, significant relationships between the Δ_L and WUE_i (photosynthesis rate/transpiration rate, P_n/T_r), WUE_n (photosynthesis rate/stomatal conductance of CO_2, P_n/g_s), WUE_y (yield/crop water consumption, Y/ET_c) and yield, or between the Δ_F and WUE_y and yield were found, respectively. There were significantly negative correlations of Δ_L with WUE_i, WUE_n, WUE_y and yield (P < 0.01) at the fruit maturation stage, or Δ_L with WUE_i and WUE_n (P < 0.01) over whole growth stage, respectively. Δ_F was negatively correlated with WUE_y, WUE_n and yield (P < 0.05), but positively correlated with ET_c (P < 0.01) over the whole growth stage. Thus Δ_L or Δ_F can compare WUE_n and WUE_y, so the stable carbon isotope discrimination method can be applied to evaluate the water use efficiency of pear-jujube tree under the regulated deficit irrigation.