Modeling the spatial pattern of farmland using GIS and multiple logistic regression: a case study of Maotiao River Basin, Guizhou Province, China

Land use change is an important topic in the field of global environmental change and sustainable development. Land use change modeling has attracted substantial attention because it helps researchers understand the mechanisms of land use change and assists regulatory bodies in formulating relevant policies. Maotiao River Basin is located in the province of Guizhou, China, which has a developed agricultural industry in the karst mountain areas. This paper selected biophysical and social–economic factors as independent variables, and constructed a multiple logistic regression of farmland spatial distribution probability by random sampling. Then, by using GIS technology and integrating the 2000 data, this study predicted the farmland spatial pattern. When the predicted map was compared with the actual farmland map for 2000, we noted that 71% of the simulation is in accordance with the 2000 farmland pattern. The result satisfactorily proves the reasonability and applicability of our model.     

哈密地区环境中^220Rn子体α潜能浓度所致居民剂量估算

用ＳｔｒａｎｄｅｎＥ．推荐的测量方法对哈密地区环境空气中２２０Ｒｎ子体α潜能浓度测量结果表明，室内、外平均值分别为５６．１和１０．２（×１０－７Ｊ·ｍ－３）。室内外２２０Ｒｎ／２２２Ｒｎ子体α潜能浓度比值分别为０．８４和０３２。２２０Ｒｎ子体所致居民有效剂量当量为２２８μＳｖ·ａ－１（集体有效剂量当量为０．９×０２ｍａｎ·Ｓｖ）。     

Performance evaluation of a sorbent tube sampling method using short path thermal desorption for volatile organic compounds

Air sampling, using sorbents, thermal desorption and gas chromatography, is a versatile method for identifying and quantifying trace levels of volatile organic compounds (VOCs). Thermal desorption can provide high sensitivity, appropropriate choices of sorbents and method parameters can accommodate a wide range of compounds and high humidity, and automated short-path systems can minimize artifacts, losses and carry-over effects. This study evaluates the performance of a short-path thermal desorption method for 77 VOCs using laboratory and field tests and a dual sorbent system (Tenax GR, Carbosieve SIII). Laboratory tests showed that the method requirements for ambient air sampling were easily achieved for most compounds, e.g., using the average and standard deviation across target compounds, blank emissions were < or = 0.3 ng per sorbent tube for all target compounds except benzene, toluene and phenol; the method detection limit was 0.05 +/- 0.08 ppb, reproducibility was 12 +/- 6%, linearity, as the relative standard deviation of relative response factors, was 16 +/- 9%, desorption efficiency was 99 +/- 28%, samples stored for 1-6 weeks had recoveries of 87 +/- 9%, and high humidity samples had recoveries of 102 +/- 12%. Due to sorbent, column and detector characteristics, performance was somewhat poorer for phenol groups, ketones, and nitrogen containing compounds. The laboratory results were confirmed in an analysis of replicate samples collected in two field studies that sampled ambient air along roadways and indoor air in a large office building. Replicates collected under field conditions demonstrated good agreement except for very low concentrations or large (> 41 volume) samples of high humidity air. Overall, the method provides excellent performance and satisfactory throughput for many applications.     

浅谈GAM与GM（1,1）模型

对ＧＡＭ水环境预测模型提出了四点不同看法，与有关作者商榷，指出ＧＭ（１，１）模型与ＧＡＭ模型二者并无优劣之差，精度亦相当。     

改进取样方法提高含油废水中CODcr值的准确度

化学需氧量(CODcr)和石油类都是中国实施水污染物排放总量控制指标,也是环境监测的常测项目.CODcr是反映水体中受还原性物质主要是有机物污染程度的综合性指标.矿物油和动、植物油统称为油类,是废水中常见的有机污染物,对CODcr的贡献较大.探索水体中CODcr值与油类物质含量之间的相关性,对CODcr值准确性的判断有一定指导意义.改进含油废水的取样方法,有利于提高CODcr测定值的准确性和代表性.     

用好防灾科技学院教育平台创建和弘扬防震减灾文化-恭贺母校升本暨校庆30周年

本文对防震减灾文化的组成、创建动力及其方法进行了探讨.初次提出了防震减灾文化的概念,并对创建防震减灾文化的目的和如何创建、弘扬防震减灾文化提出了看法和观点.     

用好防灾科技学院教育平台 创建和弘扬防震减灾文化——恭贺母校升本暨校庆30周年

本文对防震减灾文化的组成、创建动力及其方法进行了探讨。初次提出了防震减灾文化的概念，并对创建防震减灾文化的目的和如何创建、弘扬防震减灾文化提出了看法和观点。     

珍贵油料植物诸葛菜的研究

四川大学植物遗传研究室经过几年的调查研究,发现诸葛菜的农艺性状较好,分枝多、角果多,每果子粒多,千粒重较重,含油量较高,特别是油分品质优异,其营养价值高的脂肪酸如油酸和亚油酸的含量较高,分别为20.32％,和53.17％,其营养价值低的脂肪酸如亚麻酸和芥酸的含量较低,分别为4.76％和0.94％,是油菜优质育种的优异新种源,可以作为油菜远缘杂交育种亲本,并可能选育出优质油料新作物。本文对诸葛菜的开花授粉习性作了观察,对核型特点作了分析,可供育种工作的参考,诸葛菜主产中国。四川大学在国内外首先推荐这种有希望的油料新种源。     

环境影响评价中河流调查、监测方法的探讨

根据实际工作的经验，对中小河流水环境研究中的河段选择、断面布设、测量采样、污染源调查、化验分析等几个方面进行初步探讨分析。     

Heavy metals in water bodies purified by suspended substrate of rivers

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