摘要:

Prediction models were developed for wheat to assess crop growth in terms of leaf area index, dry matter production and grain yield from remotely-sensed temperature and spectral indices. The cumulative stress degree days (SDD) for the period of flowering to grain formation stage showed significantly higher correlation with dry matter (r= — 0940) and grain yield (r= —0-939) whereas that, for the period grain formation to harvest stage, showed significantly higher correlation lpar;r= —0-967) for crop water use. Significant and positive correlations between dry matter, leaf area and grain yield with infrared/red, normalised difference (ND), transformed vegetation index and greenness index were attained with the latter providing the highest degree of predictability. Spectral indices measured between flowering to milking stages gave the best prediction indicating the suitability of this period for crop growth assessment by this technique. Inter-stage sensitivity analysis by using multiple regression approach also revealed that greenness and transformed vegetation indices could provide better prediction of dry matter and grain yield. From the values of regression coefficients the jointing to beginning of milk formation period of the crop was found to be the most sensitive stage influencing the yield of crop.

ISSN:0143-1161    

DOI:10.1080/01431169308904421

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

In India 12-15 million ha of land, i.e., 3-7 per cent of the total geographical area, has been recorded as permanent pasture or grazing land. In recent years, the factors responsible for gradual loss of grassland are expanding agriculture, overstocking of domestic animals at a phenomenal rate and improper pasture and grazing land management. However, in an agriculture-based economy, like that of India, a judicious ratio has to be maintained amongst grasslands, croplands and forestlands, in order to obtain optimum results in socio-economic and ecological terms. The acquisition of sufficient and timely information on these resource components is of prime importance for judicious planning. Remote sensing data, which is now available at regular intervals, assumes a great significance. To understand the above-mentioned facts a pilot study has been conducted in the Banni grassland areas of the Kachchh district. Banni, at one time considered the largest grassland of its kind in Asia, has fallen upon sad times in the last decade. The main aim of this study is to standardize methodology for mapping and monitoring grassland through satellite data. This includes, identification of major problem areas, selection of proper season and scale. For knowing trends regarding the changing ecology of Banni areas, multi-temporal satellite data from the years 1980, 1985 and 1988 were used and the status of grassland spread, invasion ofprosopis julifloraand salinity ingress were critically observed.

ISSN:0143-1161    

DOI:10.1080/01431169308904422

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The usefulness of satellite data in forest mapping has been proved time and again all over the world. The potential use of these data in the management of National Parks in India has also been successfully demonstrated in the past. In the present study, temporal images of Landsal Thematic Mapper and IRS-1A LlSS-ll have been used to prepare a detailed forest/vegetation map for planning and management of the Rajaji National Park, Uttar Pradesh, India. IRS-1A LISS-II imagery and temporal data have provided additional information by increasing the accuracy and level of classification. Fifteen vegetation classes and four other land-use classes could be identified and mapped using large scale false colour composites (FCCs). Species composition of each of the forest/ vegetation class has also been described.

ISSN:0143-1161    

DOI:10.1080/01431169308904423

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A spectro-polarimeter operating in ten spectral bands in the visible and near-IR range has been designed and developed for the measurement of Stokes parameters of reflected radiation from the terrain surfaces under in situ conditions. The radiometric performance and the data quality of the unit have been evaluated and explained. The instrument was extensively used in the field for the collection of spectral signatures of wheat canopies. The unit was also used in the laboratory. All spectral bands were found to be useful for the measurement of absolute values of spectral irradiance and spectral radiance, while bands 1-8 were found to be useful for the measurement of polarization. This article describes the design features and specifications and gives a typical set of field observations.

ISSN:0143-1161    

DOI:10.1080/01431169308904424

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The short wavelength infrared region (0·7-3·0μm) has manifold applications in the detection and monitoring of geoenvironmental features, such as coal mine fire, oil well fire, active volcanoes, industrial hot spots, etc. These features are essentially characterized by high temperatures and often release aerosols and greenhouse gases into the atmosphere. In the present article, an attempt has been made to study the applications of Thematic Mapper (TM) Short Wavelength Infrared (SWIR) bands (4, 5 and 7) data for the detection and monitoring of these high temperature related geoenvironmental features. The rationale of using the SWIR data for temperature related studies is also discussed in brief. The pixel-integrated and sub-pixel temperatures have been calculated using the TM SWIR bands data for an active volcano (Barren Island volcano), coal mine fire (Jharia Coal Field) and industrial hot spots (Bokaro Steel Plant).

ISSN:0143-1161    

DOI:10.1080/01431169308904425

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

This article describes an Nd:YAG laser altimeter for use on board a spacecraft. The laser altimeter instrument is described along with the specifications. The instrument can be used to provide data of terrain heights as an input to digital terrain models. A discussion of the feasibility of the satellite-borne laser altimeter and safety of the laser radiation is included.

ISSN:0143-1161    

DOI:10.1080/01431169308904426

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The use of remote sensing technique in identifying probable rattan (cane) habitats in the natural forests of Kerala has been successfully demonstrated. Rattans occur as climbing palms in scattered, isolated pockets in different forest types. The heterogenous nature of the overstorey vegetation, as well as the lack of information on their tonal differentiability characterises the problems in delineating such areas from the rest of the forest. A new approach has been adopted to overcome this difficulty. Ground truth information was collected from as many locations as possible, to include all habitat conditions. A few of these data were statistically selected as Training sets for map preparation through digital image processing. The rest were used to cross-check the map and a method involving deductive and inductive analysis based on the colour signature of the overstorey vegetation applied as a key feature of this approach.

ISSN:0143-1161    

DOI:10.1080/01431169308904427

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Transportation planning deals with the generation and distribution of activity along a road network. A safe, convenient and efficient movement of goods and people requires an integration of engineering, economic, environmental, political and social aspects and an optimal allocation of these activities needs to be carefully planned. Even when geotechnical aspects cause a constraint it is possible to plan a route which optimally utilises the land. Remote sensing data acquired from airbourne space platforms and engineering surveys have offered the planner a complete picture of the land and helped to identify the location and quantity of activity from method of the Moments/Trip polygon method and the allocation technique. Cost modelling technique has been used to identify the optimum route for the user, system, non-user, government and region point of view.

ISSN:0143-1161    

DOI:10.1080/01431169308904428

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Soil information is a prerequisite for rational land-use planning for sustainable agricultural production. Landsat imagery provides a basic tool to study soil characteristics of judicious utilization of soil resources in the various development plans of a region. The Mahanadi Basin is endowed with a variety of geological formations, varied landscapes and faulted hills, dykes, intervening valleys, plateau and plains with luxuriant forest vegetation and ground water potential. The region remains undeveloped in spite of its rich natural resources. Recently an attempt to use aerial photographs as a base map was used for terrain analysis of the Mahanadi Basin. The results of the study are presented here.

ISSN:0143-1161    

DOI:10.1080/01431169308904429

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A study for District Level Planning was carried out in the Panchmahals district, Gujarat, using the concepts of the Composite Land Development Unit (CLDU) and the Service Centre Hierarchy (SCH) for natural and socioeconomic resources, respectively. The CLDU map was derived from slope, soil, ground water prospect and land-use information using GIS techniques. Alternate land-use sites for grassland, horticulture, afforestation were recommended based upon the soil-slope conditions of the CLDUs. Priority sub-watersheds in the district were identified for soil conservation measures. Analysis on SCH was based upon composite amenity index (AI).

ISSN:0143-1161    

DOI:10.1080/01431169308904430

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor