干旱区盐渍化沙地梨的定植技术初探

该研究，探讨了干旱区盐渍化沙地上，苗木类型，定植方式，生存环境地梨树定植成活率的影响。杜梨苗经耐盐性锻炼后再定植于土壤含量盐量≥０．５５％的沙地上，其成活率可达８８．３％－９３．０％，定植的平均有效成本降低１６．４０元／６６６．７ｍ＾２。杜梨苗直接定植比植梨砧木成品苗的成活率高１７．０％，沟植的树行内土壤全盐量比穴植的低０．６２％，二者苗木成活率差异明显。梨园行间种植甜菜的苹果梨年生长量为行间土地     

Can hydrochar and pyrochar affect nitrogen uptake and biomass allocation in poplars?

Positive effects of pyrochar on soil nutrient availability and plant growth are widely reported in literature. However, few studies have reported effects of hydrochars on plant nutrition. A pot trial was conducted over a period of 2 years to investigate the effect of a pyrochar (AGT) and a hydrochar (HTC) on poplar (Populus × generosa , clone AF8) growth, biomass allocation and nitrogen (N) uptake with special emphasis on the quantification (using an isotopic mass balance approach) of char‐derived nitrogen (CDN) absorbed by plants. We found that both pyrochar and hydrochar positively affected above‐ground biomass productivity in the first year, and biomass and nitrogen (N) allocation over the 2 years by reducing the allocation of resources to fine roots. By the end of the experiment, even though the total N uptake was not affected by char, the CDN was more than 24% of the total N absorbed by HTC‐treated plants compared to a negligible amount absorbed by AGT‐treated ones. Finally, char did not affect nitrogen use efficiency (NUE) in the first year of growth, but by the end of the experiment, NUE was higher in the above‐ground biomass of HTC‐treated than in AGT‐ and control poplars.     

Collection,Analysis, and Utilization of Biogas from Anaerobic Treatment of Crab Processing Waters

Abstract

Two laboratory-scale, upflow anaerobic reactors were constructed to treat blue crab (Callinectes sapidus) cooking wastewater for determination of the volume and composition of the resulting bio-gas. Both systems (A and B) consisted of two 4-liter (L) upflow anaerobic reactors and one 8-L aerobic reactor in series. The first anaerobic reactor of System A contained 240,12.7 mm foam cubes, while the first anaerobic reactor of System B contained 180 foam pieces (25.4 ×25.4 ×12.7 mm). Biogas production rates for System A ranged from 6.6 L gas/L feed to 10.0 L gas/L feed. Mean values for System B ranged from 7.1 L gas/L feed to 11.9 L gas/L feed. Methane and carbon dioxide comprised 68% and 28%, respectively, of the gas from both systems. Hydrogen sulfide averaged 1.5% and 1.4% for systems A and B, respectively. A pilot-scale biogas collection and utilization system was also constructed and successfully demonstrated. Details of the pilot-scale system design are provided in the paper to help processors better understand how the technology might be applied.     

我国碳汇林业浅析

近年来,由于温室气体CO2在大气中含量的急剧增加,导致全球变暖日趋严重。针对这一现状,我国积极倡导发展碳汇林业。文章阐述了碳汇林业的概念、碳汇林业的项目案例以及我国发展碳汇林业的重大意义,并对发展碳汇林业过程中存在的问题提出了可行性建议。     

Nutrient Management,Cultivar Development and Selection Strategies to Optimize Water Use Efficiency

Summary

Cultivars can be selected for traits that improve water use efficiency, and fertilizers and other nutrient sources also can be managed to optimize water use efficiency of a crop. Both cultivar selection and nutrient management impact water use efficiency by altering photosynthetic rate, yield, rooting characteristics, transpiration, or soil evaporation. In order to optimize water use efficiency, cultivar and nutrient decisions should be made jointly. This integrated approach will lead to improvements in water use efficiency, with an increase in productivity and profitability per unit water.     

沙漠地区农业种植技术初探

沙漠地区在没有造林或造林初期防护效益不显著情况下，农业种植受风沙危害比较严重，提高农业种植产量是我们面临的一道难题。本文对中国林科院沙漠林业实验中心井灌区第四实验场风沙环境和三年来的种植情况进行分析，得出农业防风害的措施有以下几个方面：农作物品种的选择；种植时间的调整；以增加起动风速为目的的各项抗风害措施的采用；以减小风沙流强度和目的的阻沙林和固沙工程的建造。这些措施能有效地减小和防止风沙灾害的发     

青岛梅园的建设及梅花品种的搜集与选育

在简介青岛梅园这一北方“新星”后，着重报道了其在建园中完成的两项科研成果，即①梅园快速规划设计与施工；②梅花品种的搜集、整理与新品种选育     

Foliar Application of Glycinebetaine and Salicylic Acid Improves Growth,Yield and Water Productivity of Hybrid Sunflower Planted by Different Sowing Methods

Improved planting methods and foliar application of glycinebetaine (GB) and salicylic acid (SA) can improve the water productivity in field crops under limited water supply conditions. A 2‐year field study was conducted to evaluate the possible role of different planting methods and foliar applications of GB and SA in improving the yield, quality and water productivity of hybrid sunflower (Helianthus annuus L.). The crop was planted by flat sowing (75 cm spaced rows) and ridge sowing (75 cm spaced ridges), with GB and SA applied exogenously at 100 and 0.724 mm , respectively, at both budding and flowering stages, while control plots received distilled water. Ridge sowing, rather than flat sowing, improved the biological yield, oil yield, leaf area index (LAI), crop growth rate (CGR), plant height, water‐use efficiency and final achene yield during both the years. Foliar applications of GB and SA at both the stages improved the achene yield, although foliar application of GB at flowering was the most effective. Neither the planting methods nor the foliar application of GB and SA altered the achene oil contents during both the years. Foliar application of GB and SA increased the free proline content of the leaf and GB contents at flowering but reduced the achene protein contents, whereas planting method had no effect on these attributes across the years. Of the foliar applied chemicals, GB was more effective in improving sunflower growth and yield and water productivity than SA. To conclude, ridge sowing coupled with foliar application of GB at flowering stage could be beneficial for achieving maximum yields of hybrid sunflower under relatively water limited conditions in the field.     

Efficiency of Land Utilizationand Urbanization Progress of China

Urbanization is a process that is undergoing all over the world, which will speed up in the forthcoming years, especially in China as the boom of economy. On average, urbanization level is not only depended on the speed, but theefficiency, particularly efficiency of using land resource which affects urbanization directly. This paper provided status quo of land resource utilization efficiency, indictors, methods and factors, and illustrated the reference of well land utilization, aiming at fostering urbanization in China.     

Old and New Cultivars of Soya Bean (Glycine max L.) Subjected to Soil Drying Differ in Abscisic Acid Accumulation,Water Relations Characteristics and Yield

Two old (Huangsedadou and Longxixiaohuangpi (LX)) and two new (Jindou 19 (JD) and Zhonghuang 30 (ZH)) soya bean (Glycine max (L.) Merr.) cultivars were used to investigate the influence of soil drying on the abscisic acid (ABA) accumulation in leaves, stomatal conductance (g_s), leaf water relations, osmotic adjustment (OA), leaf desiccation tolerance, yield and yield components. The greater ABA accumulation was induced by soil drying, which also inducing g_s decreased at higher soil water contents (SWC) and leaf relative water content (RWC) significantly decreased at lower SWC in the new soya bean cultivars than in the old soya bean cultivars. The soil water threshold between the value at which stomata began to close and the RWC began to decrease was significantly broader in the new cultivars than in the old cultivars. The new cultivars had significantly higher OA and lower lethal leaf water potential than old cultivars when the soil dried. The old cultivars had greater biomass, but lower grain yield than the new cultivars in well‐watered, moderate stress and severe stress conditions. Thus with soil drying, the new soya bean cultivars demonstrated greater adaptation to drought by inducing greater ABA accumulation, stomatal closure at higher SWC, enhanced OA and better water relations, associated with increased leaf desiccation tolerance, greater water use efficiency and higher yield.