Open Access Method Article

Regional Environmental Efficiency Based on a Modified Proportional DEA Model

Yuting Xuan, Wei Woo

International Journal of Environment and Climate Change, Page 64-79
DOI: 10.9734/ijecc/2018/v8i227135

With the increased attention paid to environmental and ecological issues in China, many methods have been used to evaluate the performance of ecological conservation. Scholars have evaluated environmental efficiency in the production process with undesirable outputs, and used a data envelopment analysis (DEA) model for further examination. However, previous studies do not detail the influence of uncertain factors on undesirable outputs, such as environmental capacity and risk attitude. Therefore, this study proposes and applies a modified proportional DEA model to evaluate the environmental efficiency of various textile and clothing companies located around the main stem and tributaries of the Yangtze River. The empirical results indicate that this model is more suitable to evaluate the environmental efficiency of companies in these acutely polluted regions. Based on these findings, we suggest considering environmental capacity and risk attitude in ecological conservation policies to improve environmental efficiency.

Open Access Method Article

Estimating True Species Richness and the Degree of Hierarchical Structuring of Species Abundances in Eight Frog Communities from the North-Western Ghats of India

Jean Béguinot

International Journal of Environment and Climate Change, Page 118-137
DOI: 10.9734/ijecc/2018/v8i227147

The Distribution of Species Abundances within natural communities – when properly analysed – can provide essential information regarding general aspects of the internal organisation of these communities. In particular, true species richness on the one hand and the intensity of the process of hierarchical structuring of species abundances on the other hand may be estimated independently and, thereby, can provide truly complementary information. In turn, specific issues may thereby be addressed. For example, whether one unique dominant factor or numerous combined factors are involved in the structuring process of a community can be tested contradictorily. Although these methods are not new conceptually, their implementation in common practice remains scarce. The reason is that the relevant implementation of these methods requires to be sure that virtually all member-species in the community have been sampled. As exhaustive samplings often reveal difficult to achieve in practice, an appropriate, least-biased procedure of numerical extrapolation of incomplete inventories is imperatively required.

Considering the steadily increasing threats to the environment and biodiversity, especially facing the on-going climatic change, time has come now with ever greater urgency to go beyond the apparent limits of non-exhaustive sampling and make the most of what is available in terms of recorded field data, whatever the degree of incompleteness of species inventories.

As a modest and limited attempt to concretise this wish at the local level, I try, hereafter, to highlight the importance of additional information that may be unveiled  through adequate post-analysis of a set of eight frog communities, recently inventoried by Katwate, Apte & Raut in an amphibian hot-spot in the north-western Ghats of India. At last, the likely variations of both total species richness and the intensity of hierarchical structuring of species abundance are simulated as an answer to the steadily increasing influence of the ongoing climatic change.

Open Access Method Article

Carbon Sequestration in Relation to Topographic Aspects and Land Use in Northeast of Thailand

Kazi Kaimul Islam, Somchai Anusontpornperm, Irb Kheoruenromne, Suphicha Thanachit

International Journal of Environment and Climate Change, Page 118-137
DOI: 10.9734/ijecc/2018/v8i227150

With the aim of investigating carbon sequestration and its relationship with land use in different topographical conditions, the present study carried out during March-November/2013 in mixed vegetation cover areas under forest condition, eroded bare land and cultivated lands of corn, cassava and paddy rice in Nakhon Ratchasima province, Northeast of Thailand. A total number of 72 samples {3(transects) X 6 (sampling points spreading over different land uses along toposequence) X 4 (different depths)} together with 72 undisturbed soil samples using Soil Core Samplers for the determination of soil bulk density were collected from four different depths, 0-15, 15-30, 30-45 and 45-60 cm with each comprising six spot of mini soil pit located from three transect (tran-1, tran-2 and tran-3) for laboratory analysis in this study. The estimation of soil organic carbon and calculation of the amount of carbon sequestration on the basis of transects and landscape positions up to 60 cm soil depth revealed a positive significant correlation (r = .66**) between carbon sequestration and elevation. A non-significant but positive correlation (0.269 NS) was also observed between carbon sequestration and slope but the combined effect of slope and elevation was found to be significant with CSeq (r = .56*). Among land uses, the highest amount of carbon sequestration was observed in trees and forest followed by corn, cassava, paddy rice while the lowest being in bare land with respective values of 26.10, 23.70, 19.50, 16.80 and 6.20 Mg C ha-1. Carbon sequestration was also found to be significantly correlated with depth within soil profile, showing the highest amount in surface soil and decreased gradually with increasing depth in all land use types. The highest concentration of organic carbon (4.74 g kg-1) and rate of carbon sequestration (11.07 Mg C ha-1) was found in native forest at the surface soil (0-15 cm depth) and the lowest (1.84 g kg-1 and 4.37 Mg C ha-1) mostly at the lowest depth (45-60 cm) studied. Variation in soil organic carbon under different land uses and topographic condition along toposequence are of significance for understanding the process of soil carbon sequestration.

Considering the steadily increasing threats to the environment and biodiversity, especially facing the on-going climatic change, time has come now with ever greater urgency to go beyond the apparent limits of non-exhaustive sampling and make the most of what is available in terms of recorded field data, whatever the degree of incompleteness of species inventories.

As a modest and limited attempt to concretise this wish at the local level, I try, hereafter, to highlight the importance of additional information that may be unveiled  through adequate post-analysis of a set of eight frog communities, recently inventoried by Katwate, Apte & Raut in an amphibian hot-spot in the north-western Ghats of India. At last, the likely variations of both total species richness and the intensity of hierarchical structuring of species abundance are simulated as an answer to the steadily increasing influence of the ongoing climatic change.

Open Access Original Research Article

Estimation of Carbon Stock in the Regenerating Tree Species of the Intact and Disturbed Forest Sites in Tanzania

Elly Josephat Ligate, Can Chen, Chengzhen Wu

International Journal of Environment and Climate Change, Page 80-95
DOI: 10.9734/ijecc/2018/v8i227139

Aim: Estimation of carbon in the forests located in the coast of tropics is needed to support conservation and forest monitoring strategies. This study aimed at quantifying carbon stocks in the regenerating tree species of intact forest (IFS), disturbed by agriculture (ADS) and by livestock grazing sites (LDS) to understand the importance of coastal trees in carbon stocking as part of mitigating climate change impacts.

Methodology: Thirty-three independent measurements of tree carbon stocks were carried out on 33 tree families found in the coastal zone of Tanzania. The vegetation was inventoried by means of a floristic survey of the woody component across intact, crop agriculture and livestock disturbed land use sites. The biomass was then estimated by employing the existing allometric equations for tropical forests. Thereafter, the above ground stored carbon was quantified on the sampled tree species found in each land uses.

Results: The results showed that there were significant variations (p ≤ .05) of carbon stock values across species and land uses. The average carbon (Kg/ha) stored in the regenerated adult trees was 1200 in IFS, 600 in ADS, 400 in LDS. Saplings had 0.43 in LDS, 0.07 in ADS and 0.01 in IFS. Indeed, seedlings had the average of 0.41 in IFS, 0.22 in ADS and 0.05 in LDS.

Conclusion: These findings show that crop-agriculture highly affects the regeneration potential of trees, biomass accumulation and carbon stock than livestock grazing. To restore carbon storage potential of coastal tropical forests, crop-agriculture must be discouraged, while livestock grazing can be integrated in forest management. Indeed, further studies are required to gauge the integration levels of any anthropogenic activities, so that the natural capacity of coastal tropical forests to regenerate and stock carbon is not comprised further.

Open Access Original Research Article

Introducing a Modificated Local Model of MODIS with Respect to Radiosonde Data, and Estimation of LWIR Radiation Transmission

Jabar Saydi, Javad Khalilzadeh, Safa Khazaei, Mehdi Momeni

International Journal of Environment and Climate Change, Page 96-117
DOI: 10.9734/ijecc/2018/v8i227144

Aims: Using a latitude dependent local corrected model and based on MODIS data around Mehrabad Synoptic Station of Tehran, the spectral radiance in long wavelength infrared region was modeled and calculated for total upward and downward radiation flux and direct downward radiation flux for cold and hot seasons. 

Study Design: Design of the study includes  the calculations of local atmospheric profile of the subjected region by radiosonde data, calculations of the atmospheric profile by MODIS data for same region. It presents  a latitude dependent relation for modifying the MODIS data of any point which properly could be used instead of radiosonde data at that point and finally model and calculate LWIR’s total emitted flux at different heights for the area around subjected region with local profile for both hot (June, July, August) and cold (January, February, March) seasons.[G7] [G8] 

Place and Duration of Study: Department of Optic and Laser, Faculty of science, I. H.U University, between February 2016 and December 2017.

Methodology: The radiosonde and MODIS raw data of 13 stations with different latitudes in 1995-2015 were used for modification purpose. By applying statistic calculations on raw data, the atmospheric profile was extracted. Radiosonde data were not available in any points of a region, while the MODIS data were available. A latitude dependent relation is presented in this work for modifying the MODIS data of any point which properly could be used instead of radiosonde data at that point.    

Results: The results were compared and assessed with the default profiles of sub-arctic winter and tropical models. The RMSEs for total upward, downward, and direct radiation fluxes in terms of wavelength in long wavelength infrared in cold and hot seasons were 2.45 Wm-2µ-1 and 1.722 Wm-2µ-1, respectively.

Conclusion: The results showed that local atmospheric profile plays a key role in modifying atmospheric effects on TIR hyperspectral radiance and their accurate understanding improves the quality and quantity of the radiances reaching a sensor and helps better detection of the spectral  signature of the study objectives.