经济发达地区稳定发展农业的对策

江苏省常熟市地处长江南岸阳澄湖畔,临近大中城市,距上海100km,离苏州、无锡、南通不足50km,历史上为苏南重点商品粮基地之一。因地理位置、地形、地貌及大气环流等因素所决定,常熟属北亚热带南部湿润地区,年平均气温15.5℃,年日照时数2202.9小时,年雨量1038.4mm。全市境内湖泊、河流纵横交错连结成网,有水域1.75×10~4ha,大小河流4477条。全境总面积1142.2km~2,北部较高,海拔3.11m左右,向南缓缓降低,最低地区海拔0.61m。     

The Production of Pyrethrins by Plant Cell and Tissue Cultures of Chrysanthemum cinerariaefolium and Tagetes Species

Pyrethrins, the most economically important natural insecticide, comprise a group of six closely related monoterpene esters. The industrial production is based on their extraction from Chrysanthemum cinerariaefolium (Pyrethrum) capitula. The world production of natural pyrethrins still falls short of global market demand stimulating the research in in vitro production as an alternative to conventional cultivation methods. The different biotechnological alternatives such as callus cultures, shoot and root cultures, plant cell suspension cultures, and bioconversion of precursors by means of enzymatic synthesis or genetically engineered microorganisms, as well as the progress achieved in methods for the identification and quantitation of insecticidal compounds have been reviewed. Although technology for plant cell culture exists, industrial applications have, to date, been limited due to both the low economical viability and technological feasibility at large scale. Bioconversion of readily available precursors looks more attractive, but more research is needed before this technology is used for the industrial production of pyrethrins.     

棉田生态系统能流经济阈值的初步研究

系统能流经济阈值（ＥＥＴ）为本项研究提出的新概念。它是指系统的初级生产者－作物向其它亚系统输出能量的允许临界值,由此产生的期望收益最大,系统能流经济阈值是一条仅与作用现丰量相关的动态曲线,与其他亚系统无直接关系,本文以末施药棉田为系统,提出能流经济阈值的研究方法为：建立能流动态模型;确定害虫防治代价,计算期望产出,运用计算机仿真语言对作物的能流输出参数进行优化并建立系统能流经济阈值模型。     

陕西渭北柿子园种植白三叶草对土壤养分和生物学性质的影响

种植豆科绿肥可以有效增加氮肥来源,提高水土保持能力,改善生态环境与土壤质量,是促进农业生产可持续发展的重要措施之一.本试验研究了柿子园种植白三叶草对土壤养分和生物学性质的影响,以探明果园种植豆科绿肥在土壤肥力改良与经济效益提升方面的潜力.设柿子园清耕、种植白三叶草2个处理,于2017年9月14日分别采集0～10、10～20、20～30和30～40 cm土层样品,以分析两个处理对土壤有机质、速效氮、微生物生物量碳、氮和酶活性的影响.结果表明: 与清耕相比,生草后的整个被测土层的有机质、速效氮、微生物生物量碳、氮及脲酶、蔗糖酶、过氧化氢酶、碱性磷酸酶活性均增加,其中,0～10 cm土层生草处理的有机质、微生物生物量碳增加效果显著,10～20 cm土层速效氮含量增加效果显著,0～20 cm土层中脲酶活性显著增加,而过氧化氢酶活性、蔗糖酶及土壤酶活性的几何平均值(GME)则在整个被测土层都显著增加.表明果园生草能改善土壤肥力状况,在一定程度上可减少化肥氮投入量,提高果园经济效益,是一种优良的果园栽培模式.     

陕西汉中地区经济动物研究

经济动物根据其用途可划分为 9大类 ,通过对汉中地区各类经济动物发展潜力的分析 ,汉中地区应大力发展肉用动物、药用动物和工业资源动物的养殖。在开发利用经济动物的过程中 ,应特别注意应用生物技术 ,保持生物资源的可持续发展     

Optimization of low-cost biosurfactant production from agricultural residues through response surface methodology

Biosurfactants are surface-active compounds capable of reducing surface tension and interfacial tension. Biosurfactants are produced by various microorganisms. They are promising replacements for chemical surfactants because of biodegradability, nontoxicity, and their ability to be produced from renewable sources. However, a major obstacle in producing biosurfactants at the industrial level is the lack of cost-effectiveness. In the present study, by using corn steep liquor (CSL) as a low-cost agricultural waste, not only is the production cost reduced but a higher production yield is also achieved. Moreover, a response surface methodology (RSM) approach through the Box–Behnken method was applied to optimize the biosurfactant production level. The results found that biosurfactant production was improved around 2.3 times at optimum condition when the CSL was at a concentration of 1.88 mL/L and yeast extract was reduced to 25 times less than what was used in a basic soybean oil medium (SOM). The predicted and experimental values of responses were in reasonable agreement with each other (Pred-R² = 0.86 and adj-R² = 0.94). Optimization led to a drop in raw material price per unit of biosurfactant from $47 to $12/kg. Moreover, the biosurfactant product at a concentration of 84 mg/L could lower the surface tension of twice-distilled water from 72 mN/m to less than 28 mN/m and emulsify an equal volume of kerosene by an emulsification index of (E24) 68% in a two-phase mixture. These capabilities made these biosurfactants applicable in microbial enhanced oil recovery (MEOR), hydrocarbon remediation, and all other petroleum industry surfactant applications.     

Economic comparison of enzymatic reactors and advanced oxidation processes applied to the degradation of phenol as a model compound

Abstract

Some micropollutants present in wastewaters are barely removed in sewage treatment plants. In many cases a post-treatment process based on separation and/or oxidation has to be applied. The aim of this study was the technical and economic comparison of enzymatic technologies with other advanced oxidation processes (AOPs) for the degradation of phenol. Batch and continuous enzymatic reactors, using free and immobilized manganese peroxidase (MnP, EC 1.11.1.13), were considered. Continuous degradation of phenol in an enzymatic membrane reactor was shown to be the fastest process and degradation in a continuous reactor with immobilized enzyme involved the lowest consumption of enzyme. However, the immobilization process increased the enzyme cost 100-fold. A continuous enzymatic membrane reactor gave high degradation efficiency and may be a viable technology for phenol removal when compared with other AOPs from both technical and economic points of view.     

深圳特区表面温度空间分异特征

快速城市化和人口急剧膨胀产生的热岛效应,强烈影响着城市居民生活工作的舒适度,是一种环境恶化的表现。它不仅造成城市上空污染物质的聚集、降雨量的减少等各种环境问题,而且导致城市区域内动植物行为特征的改变。因此,有必要定量分析城市的热岛效应,寻找出合理的植被配置状态减少负面影响。利用遥感数据,以我国第一个经济特区也是第一个在总体规划下创立的城市深圳特区为研究区域,采用曲面分形维数、空间自相关方法研究了深圳特区当前植被配置状态下的热岛效应空间特征表达、主要驱动力和方向性问题。结果表明：城市热岛效应显著,与道路主干道相一致,最高温度312．97K,最低温度285．80K;特区在东西向、南北向两个方向分别受到了城市扩展和地形约束的影响,呈现出明显的热岛效应梯度;存在4个主要的高温区块,冷岛的面积也较大;曲面分形、空间自相关和温度变幅揭示出福田区仍然是特区城市化和人工干扰最强烈的区域,土地利用破碎化严重,不同温度斑块呈离散分布,而盐田区由于区域发展政策和绿地建设不完善的原因呈现出较严重的连片高温区,表明城市植被分布位置在有效减少连片高温区域出现以及随之带来的巨大危害方面的效能要强于面积;各方向的剖面变化和样带的曲面与空间自相关分析揭示出不同方向的人工干扰和城市化影响,同时可以反映出一定的能流物流的通道。今后利用更高分辨率的红外遥感数据和地面物体高程数据可在城市表层不连续特征下更准确地计算表面温度,为城市能量流动和动态模拟提供支持。     

蜡梅的民族植物学研究

蜡梅(Chimonanthus praecox)是特产我国且栽培历史悠久的名贵花木,在我国栽培广泛。从民族植物学的角度对蜡梅的名称溯源、文化内涵、观赏价值及经济价值等进行了分析。阐述其色、香、姿、韵的园林美学价值和不畏严寒的文化价值以及蜡梅属植物的药用、食用、工业用等经济价值。并且对蜡梅这一重要的绿化树种在我国园林中的应用进行了分析,探讨其在园林应用中应注意的原则以及蜡梅专类园栽植和混植、群植、盆景等多种应用形式。     

新疆特有植物——野扁桃资源价值及保护利用

在野生植物资源不断消失,化石能源日益紧缺的今天,对新疆特有植物野扁桃的资源分布、经济、生态等价值以及目前存在的问题进行了论述并提出了相应地保护措施和开发利用的建议。目的是让全社会更好地利用和保护这种珍稀植物。