基于SPOT5影像多辐射校正水平的植被绿量遥感估算

选用南京市SPOT5图像的灰度值(DN)、星上辐射率(SR)、表观反射率(TOA)和地物反射率(PAC)数据,提取了两种植被指数(VI),即归一化植被指数(NDVI)和比值植被指数(RVI),并与地面实测的绿量(LVV)进行相关分析,建立了165个关系模型.结果表明,LVV与VI呈极显著的相关关系,其相关系数多以相对均质植被高于植被总体,基于灰度值高于常用的地物反射率为主.LVV-VI关系模型的R~2均值以多元线性回归模型最高(0.821),指数模型最低(0.536),而1～3次多项式模型均接近0.7.每种植被样方优选出一个模型,即阔叶林LVV-7.802 RVI_(PAC)-2.455(R~2=0.827,RMSE=0.498);针阔叶混交林LVV=-15.421 RVI_(TOA)+26.971 RVI_(DN)-8.261(R~2=0.918,RMSE=0.356);灌木LVV=-342.591 NDVI_(DN)~3-20.553 NDVI_(DN)~2+14.013 NDVI_(DN)+1.509(R~2=0.764,RMSE=0.689);草地LVV=2.934 RVI_(PAC)+2.147 RVI_(TOA)-3.193(R2=0.903,RMSE=0.464);总体植被LVV=1.789RVI_(PAC)-6.814NDVIs+4.258NDVI_(PAC)+12.854 NDVI_(DN)-0.342(R~2=0.810,RMSE=0.638).这些优选模犁的自变量包括了4种辐射校正水平下提取的两种植被指数,显示基于不同辐射校正水平的植被指数在植被LVV遥感反演中具有一定的应用潜力.     

高速铁路高填复合路堤边坡安全问题探讨

路基是高速铁路安全系统的关键和薄弱环节 ,建在软土上的高填路堤边坡是否稳定 ,更是直接关系到路基乃至整个高速铁路系统的安全 ,采用桩—网复合地基形式修建高路堤是一个好办法 ,这种路堤形式尚不多见。笔者结合其特点 ,从理论上提出了一种新的边坡安全实用计算方法 ;讨论了影响边坡安全的主要因素 ;验证了这一计算方法的合理性     

Changing scenario of Himalayan agroecosystems: loss of agrobiodiversity, an indicator of environmental change in Central Himalaya, India

Environmental, biological, socio-cultural and economic variations in the Himalayas have led to the evolution of diverse and unique traditional agroecosystems, crop species, and livestock, which help the traditional mountain farming societies to sustain themselves. During the recent past, as a result of rapid changes in land use caused by socio-cultural and economic changes and various environmental perturbations, the agrobiodiversity of the Central Himalayan agroecosystems has changed steadily. A recent survey conducted in 150 different villages located along an elevated transect of the Alaknanda catchment of the Central Himalaya revealed that over a period of two decades (1970–74 and 1990–94) the cultivated area under many traditional crops had declined significantly. A micro-level study carried out in 30 villages revealed that a series of changes had occurred in land use practices over a period of 25–30 years.The loss of agrobiodiversity and the changing socio-cultural and economic dimensions and their impacts on the sustainability of Himalayan agroecosystems are emerging as major causes of concern at local/regional/national scale, and appropriate options to meet these challenges are discussed in this paper.     

Isolation of Thiobacillus sp from aerobic sludge of distillery and dairy effluent treatment plants and its sulfide oxidation activity at different concentrations

In the present study two strains of Thiobacillus sp were isolated from aerobic sludge of distillery and dairy effluent treatment plant using standard methods of isolation and enrichment. Experiments were conducted using isolated cultures in batch bioreactor with initial sulfide concentration of 75 and 150 mg/l. The effect of initial sulfide concentration on the activity of isolated Thiobacillus sp was studied. Sulfide oxidizing capacity was also determined at different initial sulfide concentrations. The results from the study indicate the possible isolation of Thiobacillus cultures from native source and application in the full-scale reactor     

甲苯降解菌的分离、鉴定及其对甲苯的降解特性

从重庆钢铁集团焦化厂脱酚池车间污泥中分离纯化得到一株能以甲苯为惟一碳源和能源的革兰氏阴性菌。根据生理生化实验结果、菌落特征、菌体形态,初步鉴定为假单孢菌属。菌株的最佳生长条件为：pH7、温度35℃、加入量100mL培养基中加入60μL甲苯、接种量5．0％。考察了菌株对甲苯的降解特性,在甲苯质量浓度为150mg/L时,比降解速率达到0．211h^-1。     

Seasonal Variation of Toxic Benzene Emissions in Petroleum Refinery

Petroleum refineries are largest chemical industries that are responsible for the emission of several pollutants into the atmosphere. Benzene is among the most important air pollutants that are emitted by petroleum refineries, since they are involved in almost every refinery process. Volatile organic compounds (VOCs) are a major group of air pollutants, which play a critical role in atmospheric chemistry. These contribute to toxic oxidants, which are harmful to ecosystem, human health and atmosphere. The variability of pollutants is an important factor in determining human exposure to these chemicals. The ambient air concentrations of benzene were measured in several sites around the Digboi petroleum refinery, near the city of Gowahati in northeast India, during winter and summer 2004. The seasonal and spatial variations of the ambient air concentrations of this benzene were investigated and analyzed. An estimation of the contribution of the refinery to the measured atmospheric levels of benzene was also performed. The ambient air mixing ratios of benzene in a large area outside the refinery was generally low, in ppbv range, much lower than the ambient air quality standards. This article presents the temporal and spatial variation of air pollution in and around petroleum refinery and showed that no health risk due to benzene is present in the areas adjacent to the refinery.     

Real time remote monitoring of air pollutants and their online transmission to the web using internet protocol

Recent advances in both information and sensor technologies have enabled the development of Real Time Remote Monitoring (RTRM) capabilities for environmental management. An online and real time remote monitoring system for air pollution has been designed and installed at a traffic police station at Punjagutta in Hyderabad, India. The system is optimized using electrochemical sensors and a real time particulate matter analyzer. The system also monitors meteorological parameters such as temperature, humidity, rainfall, barometric pressure, wind speed and wind direction. The system periodically monitors both pollution and meteorological parameters at pre- programmed intervals of hr during peak periods and 1 hr during non peak periods of the day and continuously uploads to a predestinated web site (www.appcb.org/home.htm) using File Transfer Protocol. The web site renders a quick, simple and graphical display of air pollution levels and meteorological parameters and their significance to humans. The present paper highlights design considerations of a pollution monitoring system, system hardware and software requirements and practical limitations and future directions for real time remote monitoring of air pollution.     

Problems of livestock development in the Himalayan region

Summary This paper outlines the complexities and problems of animal husbandry in the Himalayas of India. In particular, the climatic influences of temperature, rainfall and humidity are emphasised. A wide range of possible improvements to decrease livestock malnutrition and mortality are proposed.Dr J.C. Biswas, BSc, MVSc, works in the Animal Genetics and Breeding Laboratory; Dr R. Somvanshi, MVSc, FRCVS (Sweden) is Veterinary Pathologist in charge of the Clinical Pathology and Medicine Section in Livestock Production Research and Lt.Col. Dr G.S.C. Ranga Rao, MVSc, is Veterinary Parasitologist and Joint Director. All three work at the Indian Veterinary Research Institute.     

Diet and Nutrition during Drought-An Indian Experience

In 1987 India experienced one of the century's worst droughts with two-thirds of its sown area receiving 'scanty' or 'deficient' rainfall. Delayed rains in some parts, though to some extent they relieved the water scarcity, did not brighten the prospects of agricultural production. In order to assess the diet and nutritional situation of the vulnerable population in the severely affected areas, rapid surveys were undertaken by the National Institute of Nutrition, Hyderabad, in five States of the country, namely Andhra Pradesh, Tamil Nadu, Karnataka, Orissa and Gujarat, during the months of October-December 1987. Results obtained during the current surveys are compared with the dietary situation observed in earlier droughts in the 1960s and 1970s, and it is concluded that the widespread hunger and its consequences encountered in earlier droughts could be averted, due mainly to the better food security and distribution mechanisms now available in the country.     

Microbial ecology of the soils of Indian desert

A comprehensive study on the microbial ecology of Indian desert soils was carried out. Although different groups of microorganisms e.g., fungi, actinomycetes, bacteria, Azotobacter and nitrifying bacteria were present, but in relatively low numbers, there was considerable variation in numbers from one site to another within the desert as the physicochemical characters of the soils varied. Actinomycetes formed a high proportion of the total microflora. In the majority of the soils, 80% of the fungal population belonged to the genera Aspergillus and Penicillium, while Gram-positive spore formers were the dominant group among bacteria. No significant decline in the population of microorganisms was observed during summer, in spite of high surface soil temperatures. Microbiological properties of these soils also varied depending on the type of land use pattern: grasslands, in general, supported higher numbers of microorganisms than three plantations, cultivated fields or barren land. Stabilization of shifting and sand dunes introduction of vegetation has markedly increased the soil microflora. In general the low organic matter content and poor moisture availability of desert soils were the major factors limiting optimum microbial activity.