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1.
Structural change and sustainable development   总被引:3,自引:0,他引:3  
In this paper, we show that the commonly observed decline in primary (natural resource using) sector output and employment shares, often termed structural change, can be explained as an endogenous response to the presence of nature's constraint. Structural change takes place even if consumer preferences are homothetic, and technological progress does not discriminate against the primary sector. Under certain conditions, structural change allows an open economy to grow with natural resource sustainability. Sustained and environmentally sustainable economic growth is possible even if the natural resource is exploited under open access. Well-defined property rights are neither necessary, nor sufficient for sustainable growth. We show that there is no unique relationship between natural resource endowment and the rate of economic growth over the long run. Resource-rich economies may grow faster or slower than resource-poor ones.  相似文献   
2.
Modeling exposure to particulate matter   总被引:2,自引:0,他引:2  
Exposure assessment, a component of risk assessment, links sources of pollution with health effects. Exposure models are scientific tools used to gain insights into the processes affecting exposure assessment. The purpose of this paper is to review the process and methodology of estimating inhalation exposure to particulate matter (PM) using various types of models. Three types of models are discussed in the paper. Indirect type of models are physical models that employ inventories of outdoor and indoor sources and their emission rates to identify major sources contributing to exposure to PM, and use fate and transport and indoor air quality models to estimate PM concentrations at receptor sites. PM concentrations and time spent by a subject at each receptor site are input variables to the conventional exposure model that estimates the desired exposure levels. Direct type models use measured exposure or exposure concentrations in conjunction with information obtained from questionnaires to formulate exposure regression models. Stochastic models use exposure measurements, estimates can also be used, to formulate exposure population distributions and investigate associated uncertainty and variability. Since models developed using databases from western countries are not necessarily applicable in developing countries, the difference in requirements among western and developing countries is highlighted in the paper. Employment of exposure modeling methods in developing countries requires development of local information. Such information includes local outdoor and indoor source inventories, local or regional meteorological conditions, adjustment of indoor models to reflect local building construction conditions, and use of questionnaires to obtain local time budget and activity patterns of the subject population.  相似文献   
3.
Chapter three: methodology of exposure modeling   总被引:1,自引:0,他引:1  
In this chapter, the concept of exposure assessment and its evolution is introduced, and evaluated by critically appraising the pertinent literature as it applies to exposures to Particulate Matter (PM). Exposure measurement or estimation methodologies and models are reviewed. Three exposure/measurement methodologies are assessed. Estimation methods focus on source evaluation and attribution, sources include those outdoors and indoors as well as in occupational and in-transit environments. Fate and transport models and their inputs are addressed to estimate concentrations outdoors and indoors; source attribution techniques help focus on the contributing sources. Activity pattern techniques are also reviewed and their use in exposure models to estimate inhalation exposure to PM is presented. Deterministic, regression and other stochastic models of exposure to PM are reviewed and evaluated. Strengths, limitations, assumptions and affirmations of the use of exposure assessment as an integral component of risk assessment and risk management are discussed in the conclusions and discussions section of this work.  相似文献   
4.
Environmental Science and Pollution Research - Organic dyes that are extensively released in wastewater from various industries remain the priority concern in the modern world. Therefore, a novel...  相似文献   
5.
Environment, Development and Sustainability - There has been great concern about producing, converting, or disposing of the waste obtained from different sources. Waste production is a continuous...  相似文献   
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7.
We have made an attempt to understand the significance of physiographic factors viz., altitude, aspect, slope and soil characteristics in determining the structure, composition, growth behavior and distribution of Himalayan Silver Fir (Abies pindrow Spach.) through a comparative analysis of two temperate forests. The occurrence of highest density (370 and 225 ind/ha), importance value index (213.10 and 190.60) and total basal cover (TBC; 95.72 and 51.15 m2/ha) values along with the availability of higher organic carbon (6.53 and 4.47%), nitrogen (N; 0.73 and 0.44%) and potassium (K; 621 and 319 ppm) contents in the soils just beneath the hilltops (2,650–2,800 and 2,550–2,650 m asl), on steeper slopes (45°–50° and 42°–45°) and North-East aspects have revealed better growth of A. pindrow on both the sites. Stem density positively correlated with TBC (0.771), Shannon–Wiener diversity index (H′; 0.879), OC (0.601), N (0.758) and K (0.752), whereas TBC has shown significant positive relationship with H′ (0.894), K (0.793) and N (0.716). Similarly, H′ has also shown significant positive correlation with slope (0.721), K (0.855) and N (0.791). Interestingly, positive correlation of altitude with stem density (0.557) and of slope with TBC (0.608) was noticed in the distribution of A. pindrow individuals.  相似文献   
8.
The present study was undertaken in moist temperate forest of Mandal-Chopta area in the Garhwal region of Uttarakhand, India. The aim of the present study was to assess the chemical properties of soils in relation to the forest structure and composition. Twelve forest types according to the altitude, slope aspect, and species composition were selected for the study. Chemical properties of the soil, i.e., total nitrogen (N), available phosphorus (P), available potassium (K), organic carbon (C), soil organic matter (SOM), pH and C:N ratios were analyzed for three different depths viz., (i) ??Upper?? (0?C10?cm), (ii) ??Middle?? (11?C30?cm), and (iii) ??Lower?? (31?C60?cm) in all the selected forest types. Phytosociological and diversity parameters viz. total basal cover (Gha?1), stem density (Nha?1), tree species richness (SR), Simpson concentration of dominance and Shannon?CWiener diversity index ( $ \overline{\rm H} $ ) were also calculated for each forest type. Values of N, P, K, C, SOM, C:N ratio and pH ranged from 0.17 to 0.45?%, 2.73 to 20.17?ppm, 40.67 to 261.17?ppm, 2.29 to 4.31?%, 3.95 to 7.43?%, 8.12 to 14.49 and 5.47 to 6.67, respectively. N showed a positive relationship with C and K. P was positively correlated with C and negatively correlated with altitude. P was higher in the soil of lower horizons of all the forest types. K was found to be positively correlated with altitude, C and N. pH of all the forest types was slightly acidic. C was comparatively higher in mixed broad-leaved forest types. No relationship between altitude and C was observed, which may be due to different composition of forest types along the altitudinal gradient and their differential decomposition rates. C content decreased with the depth of the soil. C showed positive correlation with N, P, and K. N showed a positive correlation with Gha?1. K showed a negative correlation with SR and $ \overline{\rm H} $ . P showed no relationship with the phytosociological parameters. This study also provides the comparisons between the results of chemical analysis of the present study with numerous other previous studies in the temperate Himalayan region of the Uttarakhand. The values of soil chemical properties of the present study in most of the forest types are on the higher end than the values previously recorded for the other similar forests of the region. The possible reason being luxuriant vegetation and undisturbed nature of these forest types, which is evident from higher values of diversity and other phytosociological parameters.  相似文献   
9.
Groundwater used for drinking and cooking was analysed for fluoride (F), and health surveys were conducted in Bodh Gaya, Amas and Bankebazaar blocks of the Gaya district, Bihar, India. Amas and Bankebazaar blocks were F endemic areas with mean F = 2.36 ± 0.23 mg/L (N = 27). Bodh Gaya was considered as control area with mean F = 0.59 ± 0.03 mg/L (N = 11). Health survey showed that more than 50 % of adults and more than 55 % of children had complaints of gastro-intestinal (GI) disturbances in the F endemic areas, while less than 20 % of adults and less than 10 % of children complained of GI problems in the control areas. Haematological analyses were conducted on age- and sex-matched fluorotic subjects (N = 93) of F endemic areas, and non-fluorotic subjects (N = 52) of control area showed lowered haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin, and mean corpuscular haemoglobin concentration in the fluorotic subjects, suggesting the occurrence of anaemia in the fluorotic subjects.  相似文献   
10.
Fluoride (F) is mainly ingested through drinking water and food. In addition to producing dental and skeletal fluorosis, excess fluoride may affect the functioning of many organs including the thyroid gland. The present study investigated the thyroid function of subjects with dental fluorosis from F-endemic areas of Gaya region, Bihar, India and compared it with control individuals from Bodh Gaya. The mean F concentration in groundwater of F-endemic area was 2.82 ± 0.18 mg/L (range 0.62–7.2 mg/L), while that of control area was 0.49 ± 0.04 mg/L (range 0.21–0.76 mg/L). Abnormal levels of T3, T4, and TSH were found in the study subjects from both control and F-endemic areas.  相似文献   
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