This study focused on identifying factors affecting the benefits of Participatory Forestry Management (PFM) income generating activities in Upper Imenti Forest and whether they are dependent on status of participation...This study focused on identifying factors affecting the benefits of Participatory Forestry Management (PFM) income generating activities in Upper Imenti Forest and whether they are dependent on status of participation in forest management through membership of Community Forest Association (CFA) or not. Cross-sectional survey research design was applied for collecting quantitative data using a semi-structured questionnaire administered to 384 households stratified on the basis of PFM participation status. Qualitative data was collected through focused group discussions using a checklist and key informant interviews using an interview schedule. Using Statistical Package for Social Sciences version 25, Binomial regression with Wald Chi-square was analyzed to identify factors perceived to be significantly influencing benefits for PFM participants and Pearson Chi-square to compare factors perceived to be affecting PFM and non-PFM participants. CFA members participation in PFM was significantly and positively affected by benefits of PFM income generating activities and forest products accessed in the forest. Benefits linked to Plantation Establishment for Livelihood Improvement System (PELIS) for CFA members were significantly reduced by enforcement of moratorium policy since February 2018, diseases and pests, poor PELIS guideline adherence and animal damage. Benefits related to state forest access for firewood by the CFA members were negatively influenced by the moratorium policy. Diseases and pests affected benefits associated with bee keeping significantly. Comparing factors under different PFM participation status, crop production was significantly affected by policy changes, pest and diseases, animal damage and PELIS guideline adherence for CFA members than for Non-CFA members. Policy changes also affected the CFA members significantly in firewood collection and access to fodder in the state forest than the Non-CFA members. Hence, sustainable community participation in Upper Imenti Forest management requires: increasing PFM benefits, addressing factors reducing benefits and enhancing active participation of CFA members in PFM related decision-making processes.展开更多
Yala swamp wetland is the largest fresh water wetland ecosystem in Kenya supporting a broad biodiversity. It comprises of River Yala, the Yala swamp, Lakes Kanyaboli, Namboyo and Sare, and a portion of Lake Victoria n...Yala swamp wetland is the largest fresh water wetland ecosystem in Kenya supporting a broad biodiversity. It comprises of River Yala, the Yala swamp, Lakes Kanyaboli, Namboyo and Sare, and a portion of Lake Victoria neighboring the swamp. Approximately 2300 ha of land have been reclaimed and has been used for large-scale agriculture resulting in mass destruction of papyrus to create room for framing. Papyrus are known to be important in phytoremediation but despite this role information is limited, lacks supportive evidence and the empirical aspect on the levels of these pollutants in relation to the papyrus biomass is limited. The study is aimed at determining the effects of Cyperus papyrus on the water and sediment quality in Yala Swamp wetland. Six sampling sites were purposefully selected to monitor the variations of the physicochemical parameters (temperature, dissolved oxygen: DO, pH, biological oxygen demand: BOD, total suspended solids: TSS, turbidity, electrical conductivity: EC and total dissolved solids: TSS) and the levels selected nutrients (phosphorus and nitrates) in water and sediments as River Yala flows through Dominion Farms, Lake Sare which surrounded by Cyperus papyrus and finally into Lake Victoria. The samples were collected in triplicates during the wet and dry seasons (May and September 2015 respectively). The physicochemical parameters were measured in situ using a Hydrolab muiltimeter while the nutrients were analyzed using UV/Vis spectroscopy. Statistical analysis was done using SAS V9.0 software. The mean temperature was 26.19˚C ± 0.71˚C, DO: 3.72 ± 1.02 Mg/l, BOD: 3.9 ± 0.32 Mg/l, pH: 7.52 ± 0.17, TDS: 109 ± 86.33, EC: 173.26 ± 13.8 μS/cm, TSS: 12.42 ± 18.51 Mg/l and Turbidity: 12.29 ± 10.03 NTU. The values varied significantly at P 0.05 among all the sites. The results show that papyrus is useful in maintaining the required levels of physicochemical parameters. The study will assist in conservation of the papyrus to help phytoremediate pollutants from Dominion farms and the adjacent farms in order to have ecologically sound wetland.展开更多
Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash cont...Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash content. In addition, many environmental sensitive organic and mineral bound elements such as Fe, Mg, Bi, AI, V, Cu, Cd, Ni, Pb, and Mn etc. remain enriched in these coals. Such characteristics are associated with more severe environmental impacts due to mining and its utilization in coal based industries. Environmental challenges include large scale landscape damage, soil erosion, loss of forest ecosystem and wildlife habitat, air, water and soil pollution. Several physical and chemical methods are reported in literature for the removal of mineral matter, total sulfur and different forms of sulfur from high sulfur coal in northeast India. This paper may help different researchers and stakeholders to understand current state of research in the field. Initiatives may be taken towards sustainable use of coal resources by adopting innovative clean technologies and by implementing effective control measures and regulatory policies.展开更多
Abstract: Migration process has become increasingly important in recent research on population and the environment. A majority of the existing migration and environment literature has focused on the environmental cau...Abstract: Migration process has become increasingly important in recent research on population and the environment. A majority of the existing migration and environment literature has focused on the environmental causes and determinants of migration. With the largest rural-to-urban migration flow in world history, and growing concerns about the environmental problems accompanying its fast economic development, China provides a particularly important case for migration and environment research. This paper reviews major migration theories and recent research on environmental effects on migration, with specific attention to the influences of en- vironmental factors on rural-to-urban labor migration in China. A comprehensive multilevel conceptual framework is developed for studying the environmental causes of rural-to-urban migration in China. The effects of land resources on household labor migration decisions in rural China are explored to illustrate the application of this framework.展开更多
In this paper we have first of all studied the interrelations among the concentrations of SO2, NO2 and PM10 and then predicted their future level of concentrations in the ambient air of Kolkata. The data collected fro...In this paper we have first of all studied the interrelations among the concentrations of SO2, NO2 and PM10 and then predicted their future level of concentrations in the ambient air of Kolkata. The data collected from West Bengal Pollution Control Board website have been used to construct second degree, third degree and four degree polynomial equations using MATLAB software. Since a curve in a small interval can be approximated by a line segment in that small interval, we have observed that better result can be achieved if we replace the curves piece meal wise in small intervals by line segments during January-April, May-August and September-December months. The multiple regression equations among the aforesaid three parameters have been established to predict the value of each parameter in terms of the remaining two. A further improvement in terms of reducing the number of dependent variables has been made using the results of correlation coefficients. Finally, we have predicted the value of each parameter in terms of only one dependent variable.展开更多
To achieve Sustainable Development Goal (SDG) in healthcare facilities (HCFs,) the provision of water, sanitation, healthcare waste management, hand hygiene and environmental cleanliness services is crucial. Good WASH...To achieve Sustainable Development Goal (SDG) in healthcare facilities (HCFs,) the provision of water, sanitation, healthcare waste management, hand hygiene and environmental cleanliness services is crucial. Good WASH services in HCFs settings have the potential to reduce healthcare acquired infections (HAIs), increase trust and uptake of healthcare services, increase efficiency and improve staff morale. To address this, a National Assessment was carried out to ascertain environmental cleanliness condition of the healthcare facilities at all levels. The assessment of healthcare waste management in the facilities was conducted in all the 26 regions of Tanzania Mainland including districts and lower healthcare facilities. A standardized checklist and tools were used to assess and monitor various aspects related to healthcare waste management using open source software for data collection (ODK). Data were analyzed using SPSS computer software. It was observed that most of permanent staff (88%) in the Healthcare facilities had knowledge on hand hygiene, but the gap was observed to the waste handlers (12%) who were not equipped with the hand hygiene knowledge. About 89% of the hand washing stations were available at mortuary units, followed by 75% at main entrance and the lowest was 3% at waste zone areas of the healthcare facilities. Hand washing materials like soap were mainly found at theaters (64%) followed by mortuary (60%) and last at waste zones. The assessment concludes that handling of healthcare wastes is not practiced to the expectations, and there is a need to strengthen the situation. The findings provide evidence for those engaged in improving HCF conditions to develop evidence-based policies and efficient programs, enhance service delivery systems, and make better use of available resources.展开更多
Of the various strategies adopted by an invasive plant species for expanding its niche breadth,phenotypic differentiation(either due to plasticity and/or adaptive evolution) is proven to be the most successful.Lately,...Of the various strategies adopted by an invasive plant species for expanding its niche breadth,phenotypic differentiation(either due to plasticity and/or adaptive evolution) is proven to be the most successful.Lately,we studied the persistence of substantial morpho-functional variations within the individuals of alien invasive plant,Parthenium hysterophorus in Chandigarh,India,through field surveys.Based on observed differences,the individuals were categorized into two morphotypes,PAand PB.PAhad higher leaf area,leaf biomass,and chlorophyll content as compared with PB.However,PBhad a higher stem circumference,stem specific density,twig dry matter content,profuse branching,bigger canopy,and better reproductive output than PA.To substantiate the persistence of intraspecific variations in P. hysterophorus and to deduce the possible genesis of these variations,we propagated both the morphotypes under experimental conditions in winter and summer.Apart from the key morpho-functional differences observed during the field studies,protein and carbohydrate metabolism were studied in leaves and roots of the propagated plants.Differences in plant metabolism were observed only during the early growth period,whereas the morpho-functional traits varied in the mature flowering plants.The effect of growth season was highly significant on all the studied morpho-functional and biochemical parameters(p ≤0.05).Parent morphotypes(P) and interactions between morphotypes and seasons significantly affected several growth parameters(p ≤0.05).The analyses revealed that the contrasting growth conditions at the time of transplantation and early growth may regulate the phenotype of P. hysterophorus.The pattern of intraspecific variations observed during the study is justified to consider morphotype PAas winter biotype and morphotype PBas summer biotype of P. hysterophorus.The study points towards the role of plasticity or a combination of genetic and environmental(G×E) factors in producing the phenotypic variability observed in the population of P. hysterophorus.展开更多
The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the less...The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the lesser Himalayas of Nepal.In total,44 water samples were collected from 22 different sites during the pre-monsoon and monsoon seasons,and 25 TEs were analyzed.Correlation matrix and principal component analysis(PCA)were used to analyze the potential relationship between the measured TEs and their source tracking.Furthermore,the water quality index(WQI),metal index(MI),and cancer index(CI)were evaluated.The TEs content in all samples were found to be within the WHO recommended guideline for drinking and domestic purposes.The dominancy order of the TEs was observed as Sr>Ba>Li>Rb>Zn>Cr>Sc>Mn>Ti>Cu>As>Ni>Co>U>V>Pb>Cs>Ga>Y>Tl>Th>Zr>Bi>Cd>Nb.The PCA analysis suggested that TEs could have natural,anthropogenic,and mixed origins.The WQI indicated that the river water is safe from a human health perspective.The MI suggested that Badigad River can be considered safer for drinking purposes,and the cancer index(CI)showed that all the reported TEs are at low-risk levels.The findings of this study could be useful for government agencies in developing more sustainable water management policies in the region.However,it is suggested that further investigations should be conducted in terms of other hydrogeochemical variables,including major ions,at spatiotemporal levels for the sustainability of the river basin.展开更多
Concerns for biodiversity loss, wildlife conservation, and habitat destruction have dominated the policy agenda worldwide for decades. Unsustainable human-induced development and negative interaction between humans an...Concerns for biodiversity loss, wildlife conservation, and habitat destruction have dominated the policy agenda worldwide for decades. Unsustainable human-induced development and negative interaction between humans and wildlife have emerged as predominant issues globally. The present study deals with human and elephant conflicts (HEC) in the Polpitigama Divisional Secretariat, Sri Lanka, which is located in the Kahalla-Pallekele elephant corridor and connects Wilpattu and Kaudulla wildlife sanctuaries. The research objectives are identifying spatial patterns of elephant habitat suitability and probable risk zones for HEC. The elephant habitat suitability and HEC risk zones were identified on spatial and temporal scales using Geographic Information System integrating Multi-Criteria Decision Analysis. Different factors, including habitat suitability, distance to roads, distance to croplands, distance to forests and protected areas, settlements, and population density, were considered to determine HEC risk zones in the area. Topography, water, and vegetation criteria are considered when determining elephant habitat suitability. The results of the Analytic Hierarchy Process run the spatially explicit model. The results revealed that of the total area, 15.3% is very highly suitable for elephant habitats, while the least suitable areas contribute only 4%. About 33.8% of the area is moderately suitable for elephants. The risk map indicates that 23.7% of the total area is under very high risk for HEC, and the least risk areas only account for 5.4%. About 26.2% of the area falls under the moderate risk zone for HEC. Since the model considered three aspects of HEC, it will help policymakers in wildlife conservation to avoid and minimize the HEC.展开更多
This study aimed to evaluate the anti-hyperglycemic and antioxidant role of Actinidia deliciosa(kiwifruits)aqueous extract in streptozotocin-treated rats.Animals were distributed into;control,A.deliciosa aqueous extra...This study aimed to evaluate the anti-hyperglycemic and antioxidant role of Actinidia deliciosa(kiwifruits)aqueous extract in streptozotocin-treated rats.Animals were distributed into;control,A.deliciosa aqueous extract(ADAE;1 g/kg orally),streptozotocin(STZ;50 mg/kg,i.p,single dose),and STZ plus ADAE,respectively.Results showed that ADAE had high antioxidant and radical scavenging potency.Elevation in blood sugar level,lipid peroxidation(LPO),kidney function biomarkers,and perturbations in hematological parameters were observed in diabetic rats.While,enzymatic and non-enzymatic antioxidants,protein content,and alkaline phosphatase(ALP)activity declined.Furthermore,histological,immunohistochemical alpha-smooth muscle actin immunoreactivity(α-SMA-ir)and histochemical(collagen,total protein,DNA,and RNA)alterations were observed in rat kidneys.Moreover,STZ produced upregulation of inflammatory associated genes(tumor necrosis factor-alpha;TNF-αand transforming growth factorβ1;TGF-β1)and triggered apoptosis by upregulating apoptotic related gene[Bcl2-associated X protein(Bax)]and downregulating anti-apoptotic related gene B-cell lymphoma-2(Bcl-2)based on real-time PCR data.Moreover,diabetic rats administered with ADAE showed significant restoration in LPO,antioxidant status,and biochemical indices besides tissue architecture,and genes improvement regarding STZ group.Conclusively,A.deliciosa has a valuable ameliorative infl uence and can restore glucose levels and improve kidney dysfunction in diabetic rats.展开更多
Land surface temperature(LST)is a crucial parameter for understanding the Earth's surface energy balance,which provides insights into climate dynamics and local environmental conditions.Thus,the present study aims...Land surface temperature(LST)is a crucial parameter for understanding the Earth's surface energy balance,which provides insights into climate dynamics and local environmental conditions.Thus,the present study aims to evaluate the spatial and elevation-wise trends in the daytime,nighttime,and mean LST across the Indus River Basin(IRB)using MODIS 8-day product for the period between 2002 and 2022.The elevation,cloud cover,and land cover type data are used for explaining the emerging LST trends.The Theil slope estimator and MannKendall significance test were used for estimating the seasonal and annual LST trends.The findings show warming in mean daytime(0.020-0.024℃/yr)(except winter and post-monsoon),nighttime(0.013-0.049℃/yr),and mean(0.001-0.042℃/yr)LST in all the seasons(highest in monsoon).The annual mean nighttime LST(0.025℃/yr)is rising significantly faster than the mean daytime LST(0.0016℃/yr),showing the presence of a“nighttime warming effect”,which possibly increases human discomfort,particularly during the warm pre-monsoon and humid monsoon season.Elevation-dependent warming(EDW)is predominant in mean daytime LST in two elevation zones,namely(i)0-3 km and(ii)above 4 km,in all seasons,except in post-monsoon.In contrast,EDW in mean nighttime LST is observed up to 3 km and above 6 km in the basin in all the seasons,excluding post-monsoon.The warming trend in LST may be attributed to rising atmospheric moisture,cloud cover,declining snow cover,and changes in land cover to non-vegetated land.However,further investigations will involve exploring the underlying factors contributing to the observed anomalies in nighttime LST,considering variables such as regional energy balance and atmospheric stability.This research contributes to an understanding of the thermal dynamics in the mountain basin,aiding in climate studies,land management,and the development of effective adaptation strategies in the IRB.展开更多
The hydro-geochemistry and isotopic variations in groundwater,coupled with sediment geochemistry,were investigated in the Middle Gangetic Plain,India,to better understand the aquifer dynamics that influence the arseni...The hydro-geochemistry and isotopic variations in groundwater,coupled with sediment geochemistry,were investigated in the Middle Gangetic Plain,India,to better understand the aquifer dynamics that influence the arsenic(As)evolution and mobilization.Eighty-four groundwater samples,thirteen River water samples,and two sediment cores(33 mbgl)were studied.The samples were analyzed for major ions and trace metals,including As and stable isotopic variability(δ^(2)H,δ^(18)O,andδ^(13)C).The study area was categorized into older and younger alluvium based on existing geomorphological differences.Younger alluvium exhibits higher As enrichment in sediment and groundwater,ranging of 2.59–31.52 mg/kg and bdl to 0.62 mg/L.Groundwater samples were thermodynamically more stable with As(OH)_(3)species ranging from 88.5%to 91.4%and FeOOH from 69%to 81%,respectively.PHREEQC and mineralogical analysis suggested goethite and siderite act as a source and sink for As.However,statistical analysis suggested reductive dissolution as the primary mechanism for As mobilization in the study area.Spatio-temporal analysis revealed elevated concentrations of As in the central and northeastern regions of the study area.Stable isotope(δ^(2)H andδ^(18)O)analysis inferred active recharge conditions primarily driven by precipitation.The depleted d-excess value and enrichedδ^(18)O in the groundwater of younger alluvium indicate the effect of groundwater recharge with significant evaporation enrichment.Groundwater recharge potentially decreased the quantity of arsenic in groundwater,whereas evaporation enrichment increased it.Rainwater infiltration during recharge introduces oxygenated water into the aquifer,leading to changes in the redox conditions and facilitating biogeochemical reactions.The carbon isotope(δ^(13)C)results suggest that high microbial activity in younger alluvium promotes As leaching from sediment into the groundwater.展开更多
The energy transition challenges faced by modern civilization have significantly enhanced the demand for critical metals like lithium resulting in improved methods to explore,extract,and utilize these metals.In this c...The energy transition challenges faced by modern civilization have significantly enhanced the demand for critical metals like lithium resulting in improved methods to explore,extract,and utilize these metals.In this comprehensive review,we discuss the different types of lithium resources,factors,and mechanisms controlling lithium enrichment in various geological settings including terrestrial and marine environments.Diverse exploration strategies including geological,geophysical,mineralogical,geochemical,and remote sensing techniques including drone-based techniques for lithium exploration studies in different terranes are summarized.An overview of the mining techniques,including beneficiation and extraction,and their principles,mechanisms,operations,and comparison of the various approaches and compatibility with different types of lithium deposits for obtaining maximum yield are evaluated.Lithium isotopic studies are useful in understanding geological processes such as past weathering events and riverine input into the oceans,as well as in understanding the source of lithium in diverse types of deposits.We also highlight the recent developments in other areas such as recycling,environmental impact,and state-of-the-art analytical techniques for determining lithium in different lithium ore deposits and other geological materials.Our overview provides the latest developments and insights in the various sectors related to lithium and prompt further developments to meet the growing demand for this valuable metal as the world transforms to clean energy.展开更多
Chemometric techniques and pollution assessment indices were applied to determine the source and intensity of pollution in the Sirsa River, Himachal Pradesh,India. Results show EC, Cr, Fe, Mn, and Ni were above the pe...Chemometric techniques and pollution assessment indices were applied to determine the source and intensity of pollution in the Sirsa River, Himachal Pradesh,India. Results show EC, Cr, Fe, Mn, and Ni were above the permissible limit as per the Bureau of Indian Standards.The heavy metal pollution index(HPI) and contamination index(Cd) provided contrasting outcome and poor correlation was observed. A heavy metal evaluation index(HEI)method was developed using a multiple of the mean and correlation coefficient values to provide an alternative pollution classification. The criteria of HEI adopted for reclassification of HPI and Cdproduced comparable results; 40 % samples were labeled as low contamination,50 % as medium contamination, and 10 % as high contamination for all indices. Principal component analysis along with cluster analysis was used to identify the main factors responsible for degradation of water quality,namely discharge of industrial effluent, river bed mining,agricultural runoff, and minor natural or geogenic input.The methods and chemometric study proposed here can be used as effective tools to gather information about water quality and water resource management.展开更多
The present study focused on the hydrochemistry of groundwater in parts of Chandauli-Varanasi region to assess the quality of groundwater for determining its suitability for drinking and agricultural purposes. Urbaniz...The present study focused on the hydrochemistry of groundwater in parts of Chandauli-Varanasi region to assess the quality of groundwater for determining its suitability for drinking and agricultural purposes. Urbanization and agriculture activities have a lot of impacts on the groundwater quality of the study area. A total of 70 ground water samples were collected randomly from different sources viz. hand pump, dug wells and bore wells, and analyzed for major cations and anions. The domination of cations and anions was in the order of Na > Ca > Mg > K and HCO3 > Cl > SO4 > NO3 > F. The Piper classification for hydrogeochemical facies indicates that alkaline earth exceeds alkalis and weak acids exceed strong acid. Water quality index rating was calculated to quantify overall water quality for human consumption. Out of 70 groundwater samples, 7% and 10% samples exhibit water unsuitable for drinking purposes in pre- and post-monsoon, respectively, due to effective leaching of ions, direct discharge of domestic effluents and agricultural activities. Residual sodium carbonate values revealed that 6% sample is not suitable for irrigation purposes in both the seasons due to low permeability of the soil. The calculated values of PI indicate that the water for irrigation uses is excellent to good quality in both seasons. As per Wilcox’s diagram and US salinity laboratory classification, most of the groundwater samples are suitable for irrigation except one sample which is unsuitable for irrigation purposes. The overall quality of groundwater in post-monsoon season in all chemical constituents is on the higher side due to dissolution of surface pollutants during the infiltration and percolation of rainwater at few places due to agricultural and domestic activities.展开更多
This study was conducted to investigate the dissipation pattern and runoff of herbicides to the river basin from the paddy fields. Pesticide paddy field model(PADDY) was applied to predict herbicide concentration in p...This study was conducted to investigate the dissipation pattern and runoff of herbicides to the river basin from the paddy fields. Pesticide paddy field model(PADDY) was applied to predict herbicide concentration in paddy fields. A field study was conducted in a paddy farm of Higashi Hiroshima City, Hiroshima Prefecture, Japan in the year of 2003 paddy season. The herbicides were mefenacet, thiobencarb, and bensulfuron methyl. The sample water was analyzed by using gas chromatography and HPLC after solid phase extraction. Predicted dissipation rate of thiobencarb in paddy water was higher(DT_ 50 = 4 36) than that measured, with a lower k value(-0 069). Two weeks after application no thiobencarb was detected in the drainage channel and down stream. In the down stream, thiobencarb was detected until 3 d after application, with a range of 0 02% to 0 08% of applied herbicide. The predicted dissipation rate(k) and half-life(DT_ 50 ) of mefenacet was not significantly different from that of measured. In the drainage channel, upstream and downstream mefenacet was found during the whole study period. In downstream, the maximum concentration of mefenacet was present 0 61% of applied in the paddy field on 3DAH. The dissipation rate(k) of BSM varied from -0 0860 to -0 1059 to with half-life(DT_ 50 ) 3 5 and 2 84 d. In upstream water, no BSM was detected except trace amounts(0 01 μg/L) at 3 d after application. However, in the drainage channel 8%, 6% and 1 58% of applied BSM was present at 0, 1 and 3 d after application respectively. In the down stream, the highest concentration was 1 06%, shortly after application.展开更多
The population structure and regeneration status of Magnolia punduana Hk. f. & Th., an endemic tree species of northeast India were investigated in fragmented forests in the Jarain Hills and in adjoining areas of ...The population structure and regeneration status of Magnolia punduana Hk. f. & Th., an endemic tree species of northeast India were investigated in fragmented forests in the Jarain Hills and in adjoining areas of Meghalaya state. The population structure was discontinuous in all the fragments with the absence of individuals in higher diameter classes. The number of individuals increased with the size of the fragment patches(p < 0.004). The density of mature trees(≥5 cm dbh) was high(24–30 individuals ha-1) in the largest fragment(>105 ha). The number of seedlings and saplings were also higher in the larger fragments. Human-related disturbances had a negative impact on the species population(p<0.002). Variation in the population density in different forest patches has been attributed to fragment size, site characteristics and ongoing human disturbances. The restricted distribution of the species coupled withexploitation and habitat destruction underlines the need for its conservation.展开更多
Most community forests in hill regions of northeast India have been managed by traditional local institutions for centuries and most of these institutions remain functional even today. Higher forest coverage on privat...Most community forests in hill regions of northeast India have been managed by traditional local institutions for centuries and most of these institutions remain functional even today. Higher forest coverage on private and community lands as compared to government land indicates that traditional institutions effectively manage community forests in the region. The present study was conducted through a survey of literature and field work using participatory research tools viz., PRA exercises, group discussions and questionnaire interviews with key informants in northeast India. We categorized the institutions involved in conservation and management of forests into three major types: traditional, quasi-traditional and modern. Traditional institutions with hierarchal structure were found in all states and are intact and functional in the state of Meghalaya. Quasi-traditional institutions, a blend of traditional and modern institutions were prevalent in Nagaland while modern institutions have almost replaced traditional institutions in Mizoram. We recorded at least eleven types of community forests viz., group of village forest, village forest, restricted forest, sacred forest, clan forest, cemetery forest, regeneration forest, bamboo forest, recreation forest, village reserved forest and medicinal plantation in villages of three states. The tribal people, through long-term trial and error experiments, have developed an elaborate, functional and generally democratic system of conservation and management of forests and associated natural ecosystems. Several forest and natural resource management lessons can be learnt from the institutional structure and decision making system of the evolving and dynamic institutions of tribal communities of the region.展开更多
Wind power is a safe form of renewable energy and is one of the most promising alternative energy sources. Worldwide, the wind power industry has been rapidly growing recently. It is crucial that the locating of new p...Wind power is a safe form of renewable energy and is one of the most promising alternative energy sources. Worldwide, the wind power industry has been rapidly growing recently. It is crucial that the locating of new projects must address both environmental and social concerns. The Red Sea shoreline in Egypt provides excellent wind power potential sites for the Red Sea Governorate. In this study, appropriate zones for wind power farms were mapped using remotely sensed data and a GIS-based model namely Spatial Multi-Criteria Evaluation (SMCE). This model incorporated several criteria, two sets of factors and a set of constraints. First, resource factors included wind speed, elevation zones used to derive the wind power density. Second, economic factors included distances from urban areas, roads and power-lines. Third, land constraints were excluded from the evaluation. The land constraints set included land slope angles, shoreline, urban areas, protectorates airports and ecologically sensitive and historical areas. The Analytical Hierarchy Process was used to assign the criteria relative weights. The weighted criteria and constraints maps were combined in the MCE model. The model identified the zones with potential wind power energy. Such zones were found to exist along the northern parts of the Red Sea shoreline. Some of which are unsuitable due to their location within a sensitive eco-system, high slopes and/or a nearby airport. By excluding such land constrains, the model identified the most appropriate zones satisfying all assigned suitability conditions for wind farms. Ideal zones amount to 706 sq. km with suitability values ranging from 83% to 100% and highly suitable zones amount to 3781 sq. km having suitability values ranging from 66% to 83%.展开更多
Distribution and enrichment of six elements (iron, zinc, copper, lead, cadmium and manganese) in surface bed sediments, collected from seventeen selected locations during pre-monsoon and postmonsoon periods, of the tr...Distribution and enrichment of six elements (iron, zinc, copper, lead, cadmium and manganese) in surface bed sediments, collected from seventeen selected locations during pre-monsoon and postmonsoon periods, of the tropical Chottanagpur plateau river Subarnarekha along with the ecological risks involved were investigated. Owing to the rich occurrence of mineral resources, the Subarnarekha river basin has a large scale presence of industrial and mining units especially in the Indian State of Jharkhand. An assessment, which involved examining distribution pattern of elements, comparative studies with sediment quality guidelines (SQGs) and geochemical background values and a sequential and integrated index analyses approach (containing contamination factor (CF), pollution load index (PLI), contamination degree (CD), enrichment factor (EF), geo-accumulation index (Igeo) and potential ecological risk index (PERI)), was followed to estimate enrichment and risks of elements in the bed sediments. Sediments collected from areas having abundance of population, industrial conglomerates and mining units recorded elevated element concentrations, which exceeded SQGs, and significantly higher values of CF, CD, PLI, EF, Igeo and PERI. Cadmium demonstrated surprising regularity in its enrichment;contributed most to the ecological risks;and high toxicity risks due to cadmium exceeded 64% of the sites. Moreover, chronic exposures of other elements would also lead to similar ecological risks. In addition to revealing potential ecological risks due to cadmium and other elements our investigation markedly highlighted anthropogenic control over sediment quality deterioration and some immediate sediment quality management strategies are needed to remediate and control river bed contamination.展开更多
文摘This study focused on identifying factors affecting the benefits of Participatory Forestry Management (PFM) income generating activities in Upper Imenti Forest and whether they are dependent on status of participation in forest management through membership of Community Forest Association (CFA) or not. Cross-sectional survey research design was applied for collecting quantitative data using a semi-structured questionnaire administered to 384 households stratified on the basis of PFM participation status. Qualitative data was collected through focused group discussions using a checklist and key informant interviews using an interview schedule. Using Statistical Package for Social Sciences version 25, Binomial regression with Wald Chi-square was analyzed to identify factors perceived to be significantly influencing benefits for PFM participants and Pearson Chi-square to compare factors perceived to be affecting PFM and non-PFM participants. CFA members participation in PFM was significantly and positively affected by benefits of PFM income generating activities and forest products accessed in the forest. Benefits linked to Plantation Establishment for Livelihood Improvement System (PELIS) for CFA members were significantly reduced by enforcement of moratorium policy since February 2018, diseases and pests, poor PELIS guideline adherence and animal damage. Benefits related to state forest access for firewood by the CFA members were negatively influenced by the moratorium policy. Diseases and pests affected benefits associated with bee keeping significantly. Comparing factors under different PFM participation status, crop production was significantly affected by policy changes, pest and diseases, animal damage and PELIS guideline adherence for CFA members than for Non-CFA members. Policy changes also affected the CFA members significantly in firewood collection and access to fodder in the state forest than the Non-CFA members. Hence, sustainable community participation in Upper Imenti Forest management requires: increasing PFM benefits, addressing factors reducing benefits and enhancing active participation of CFA members in PFM related decision-making processes.
文摘Yala swamp wetland is the largest fresh water wetland ecosystem in Kenya supporting a broad biodiversity. It comprises of River Yala, the Yala swamp, Lakes Kanyaboli, Namboyo and Sare, and a portion of Lake Victoria neighboring the swamp. Approximately 2300 ha of land have been reclaimed and has been used for large-scale agriculture resulting in mass destruction of papyrus to create room for framing. Papyrus are known to be important in phytoremediation but despite this role information is limited, lacks supportive evidence and the empirical aspect on the levels of these pollutants in relation to the papyrus biomass is limited. The study is aimed at determining the effects of Cyperus papyrus on the water and sediment quality in Yala Swamp wetland. Six sampling sites were purposefully selected to monitor the variations of the physicochemical parameters (temperature, dissolved oxygen: DO, pH, biological oxygen demand: BOD, total suspended solids: TSS, turbidity, electrical conductivity: EC and total dissolved solids: TSS) and the levels selected nutrients (phosphorus and nitrates) in water and sediments as River Yala flows through Dominion Farms, Lake Sare which surrounded by Cyperus papyrus and finally into Lake Victoria. The samples were collected in triplicates during the wet and dry seasons (May and September 2015 respectively). The physicochemical parameters were measured in situ using a Hydrolab muiltimeter while the nutrients were analyzed using UV/Vis spectroscopy. Statistical analysis was done using SAS V9.0 software. The mean temperature was 26.19˚C ± 0.71˚C, DO: 3.72 ± 1.02 Mg/l, BOD: 3.9 ± 0.32 Mg/l, pH: 7.52 ± 0.17, TDS: 109 ± 86.33, EC: 173.26 ± 13.8 μS/cm, TSS: 12.42 ± 18.51 Mg/l and Turbidity: 12.29 ± 10.03 NTU. The values varied significantly at P 0.05 among all the sites. The results show that papyrus is useful in maintaining the required levels of physicochemical parameters. The study will assist in conservation of the papyrus to help phytoremediate pollutants from Dominion farms and the adjacent farms in order to have ecologically sound wetland.
文摘Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash content. In addition, many environmental sensitive organic and mineral bound elements such as Fe, Mg, Bi, AI, V, Cu, Cd, Ni, Pb, and Mn etc. remain enriched in these coals. Such characteristics are associated with more severe environmental impacts due to mining and its utilization in coal based industries. Environmental challenges include large scale landscape damage, soil erosion, loss of forest ecosystem and wildlife habitat, air, water and soil pollution. Several physical and chemical methods are reported in literature for the removal of mineral matter, total sulfur and different forms of sulfur from high sulfur coal in northeast India. This paper may help different researchers and stakeholders to understand current state of research in the field. Initiatives may be taken towards sustainable use of coal resources by adopting innovative clean technologies and by implementing effective control measures and regulatory policies.
基金funded by dissertation research grants from the Geography and Spatial Sciences Program of the National Science Foundation,the Worldwide Universities Network,and the Rural Sociological Society
文摘Abstract: Migration process has become increasingly important in recent research on population and the environment. A majority of the existing migration and environment literature has focused on the environmental causes and determinants of migration. With the largest rural-to-urban migration flow in world history, and growing concerns about the environmental problems accompanying its fast economic development, China provides a particularly important case for migration and environment research. This paper reviews major migration theories and recent research on environmental effects on migration, with specific attention to the influences of en- vironmental factors on rural-to-urban labor migration in China. A comprehensive multilevel conceptual framework is developed for studying the environmental causes of rural-to-urban migration in China. The effects of land resources on household labor migration decisions in rural China are explored to illustrate the application of this framework.
文摘In this paper we have first of all studied the interrelations among the concentrations of SO2, NO2 and PM10 and then predicted their future level of concentrations in the ambient air of Kolkata. The data collected from West Bengal Pollution Control Board website have been used to construct second degree, third degree and four degree polynomial equations using MATLAB software. Since a curve in a small interval can be approximated by a line segment in that small interval, we have observed that better result can be achieved if we replace the curves piece meal wise in small intervals by line segments during January-April, May-August and September-December months. The multiple regression equations among the aforesaid three parameters have been established to predict the value of each parameter in terms of the remaining two. A further improvement in terms of reducing the number of dependent variables has been made using the results of correlation coefficients. Finally, we have predicted the value of each parameter in terms of only one dependent variable.
文摘To achieve Sustainable Development Goal (SDG) in healthcare facilities (HCFs,) the provision of water, sanitation, healthcare waste management, hand hygiene and environmental cleanliness services is crucial. Good WASH services in HCFs settings have the potential to reduce healthcare acquired infections (HAIs), increase trust and uptake of healthcare services, increase efficiency and improve staff morale. To address this, a National Assessment was carried out to ascertain environmental cleanliness condition of the healthcare facilities at all levels. The assessment of healthcare waste management in the facilities was conducted in all the 26 regions of Tanzania Mainland including districts and lower healthcare facilities. A standardized checklist and tools were used to assess and monitor various aspects related to healthcare waste management using open source software for data collection (ODK). Data were analyzed using SPSS computer software. It was observed that most of permanent staff (88%) in the Healthcare facilities had knowledge on hand hygiene, but the gap was observed to the waste handlers (12%) who were not equipped with the hand hygiene knowledge. About 89% of the hand washing stations were available at mortuary units, followed by 75% at main entrance and the lowest was 3% at waste zone areas of the healthcare facilities. Hand washing materials like soap were mainly found at theaters (64%) followed by mortuary (60%) and last at waste zones. The assessment concludes that handling of healthcare wastes is not practiced to the expectations, and there is a need to strengthen the situation. The findings provide evidence for those engaged in improving HCF conditions to develop evidence-based policies and efficient programs, enhance service delivery systems, and make better use of available resources.
文摘Of the various strategies adopted by an invasive plant species for expanding its niche breadth,phenotypic differentiation(either due to plasticity and/or adaptive evolution) is proven to be the most successful.Lately,we studied the persistence of substantial morpho-functional variations within the individuals of alien invasive plant,Parthenium hysterophorus in Chandigarh,India,through field surveys.Based on observed differences,the individuals were categorized into two morphotypes,PAand PB.PAhad higher leaf area,leaf biomass,and chlorophyll content as compared with PB.However,PBhad a higher stem circumference,stem specific density,twig dry matter content,profuse branching,bigger canopy,and better reproductive output than PA.To substantiate the persistence of intraspecific variations in P. hysterophorus and to deduce the possible genesis of these variations,we propagated both the morphotypes under experimental conditions in winter and summer.Apart from the key morpho-functional differences observed during the field studies,protein and carbohydrate metabolism were studied in leaves and roots of the propagated plants.Differences in plant metabolism were observed only during the early growth period,whereas the morpho-functional traits varied in the mature flowering plants.The effect of growth season was highly significant on all the studied morpho-functional and biochemical parameters(p ≤0.05).Parent morphotypes(P) and interactions between morphotypes and seasons significantly affected several growth parameters(p ≤0.05).The analyses revealed that the contrasting growth conditions at the time of transplantation and early growth may regulate the phenotype of P. hysterophorus.The pattern of intraspecific variations observed during the study is justified to consider morphotype PAas winter biotype and morphotype PBas summer biotype of P. hysterophorus.The study points towards the role of plasticity or a combination of genetic and environmental(G×E) factors in producing the phenotypic variability observed in the population of P. hysterophorus.
文摘The consumption of contaminated river water can have severe effects on human health.This study aims to investigate the trace elements(TEs)content and their health risk assessment in the Badigad River Basin in the lesser Himalayas of Nepal.In total,44 water samples were collected from 22 different sites during the pre-monsoon and monsoon seasons,and 25 TEs were analyzed.Correlation matrix and principal component analysis(PCA)were used to analyze the potential relationship between the measured TEs and their source tracking.Furthermore,the water quality index(WQI),metal index(MI),and cancer index(CI)were evaluated.The TEs content in all samples were found to be within the WHO recommended guideline for drinking and domestic purposes.The dominancy order of the TEs was observed as Sr>Ba>Li>Rb>Zn>Cr>Sc>Mn>Ti>Cu>As>Ni>Co>U>V>Pb>Cs>Ga>Y>Tl>Th>Zr>Bi>Cd>Nb.The PCA analysis suggested that TEs could have natural,anthropogenic,and mixed origins.The WQI indicated that the river water is safe from a human health perspective.The MI suggested that Badigad River can be considered safer for drinking purposes,and the cancer index(CI)showed that all the reported TEs are at low-risk levels.The findings of this study could be useful for government agencies in developing more sustainable water management policies in the region.However,it is suggested that further investigations should be conducted in terms of other hydrogeochemical variables,including major ions,at spatiotemporal levels for the sustainability of the river basin.
文摘Concerns for biodiversity loss, wildlife conservation, and habitat destruction have dominated the policy agenda worldwide for decades. Unsustainable human-induced development and negative interaction between humans and wildlife have emerged as predominant issues globally. The present study deals with human and elephant conflicts (HEC) in the Polpitigama Divisional Secretariat, Sri Lanka, which is located in the Kahalla-Pallekele elephant corridor and connects Wilpattu and Kaudulla wildlife sanctuaries. The research objectives are identifying spatial patterns of elephant habitat suitability and probable risk zones for HEC. The elephant habitat suitability and HEC risk zones were identified on spatial and temporal scales using Geographic Information System integrating Multi-Criteria Decision Analysis. Different factors, including habitat suitability, distance to roads, distance to croplands, distance to forests and protected areas, settlements, and population density, were considered to determine HEC risk zones in the area. Topography, water, and vegetation criteria are considered when determining elephant habitat suitability. The results of the Analytic Hierarchy Process run the spatially explicit model. The results revealed that of the total area, 15.3% is very highly suitable for elephant habitats, while the least suitable areas contribute only 4%. About 33.8% of the area is moderately suitable for elephants. The risk map indicates that 23.7% of the total area is under very high risk for HEC, and the least risk areas only account for 5.4%. About 26.2% of the area falls under the moderate risk zone for HEC. Since the model considered three aspects of HEC, it will help policymakers in wildlife conservation to avoid and minimize the HEC.
文摘This study aimed to evaluate the anti-hyperglycemic and antioxidant role of Actinidia deliciosa(kiwifruits)aqueous extract in streptozotocin-treated rats.Animals were distributed into;control,A.deliciosa aqueous extract(ADAE;1 g/kg orally),streptozotocin(STZ;50 mg/kg,i.p,single dose),and STZ plus ADAE,respectively.Results showed that ADAE had high antioxidant and radical scavenging potency.Elevation in blood sugar level,lipid peroxidation(LPO),kidney function biomarkers,and perturbations in hematological parameters were observed in diabetic rats.While,enzymatic and non-enzymatic antioxidants,protein content,and alkaline phosphatase(ALP)activity declined.Furthermore,histological,immunohistochemical alpha-smooth muscle actin immunoreactivity(α-SMA-ir)and histochemical(collagen,total protein,DNA,and RNA)alterations were observed in rat kidneys.Moreover,STZ produced upregulation of inflammatory associated genes(tumor necrosis factor-alpha;TNF-αand transforming growth factorβ1;TGF-β1)and triggered apoptosis by upregulating apoptotic related gene[Bcl2-associated X protein(Bax)]and downregulating anti-apoptotic related gene B-cell lymphoma-2(Bcl-2)based on real-time PCR data.Moreover,diabetic rats administered with ADAE showed significant restoration in LPO,antioxidant status,and biochemical indices besides tissue architecture,and genes improvement regarding STZ group.Conclusively,A.deliciosa has a valuable ameliorative infl uence and can restore glucose levels and improve kidney dysfunction in diabetic rats.
基金the Banaras Hindu University,Varanasi,Uttar Pradesh(India),for providing a seed grant(Letter No.R/Dev/D/IoE/Equipment/SeedGrantII/2022-23/52078)under the Institute of Eminence(IoE)。
文摘Land surface temperature(LST)is a crucial parameter for understanding the Earth's surface energy balance,which provides insights into climate dynamics and local environmental conditions.Thus,the present study aims to evaluate the spatial and elevation-wise trends in the daytime,nighttime,and mean LST across the Indus River Basin(IRB)using MODIS 8-day product for the period between 2002 and 2022.The elevation,cloud cover,and land cover type data are used for explaining the emerging LST trends.The Theil slope estimator and MannKendall significance test were used for estimating the seasonal and annual LST trends.The findings show warming in mean daytime(0.020-0.024℃/yr)(except winter and post-monsoon),nighttime(0.013-0.049℃/yr),and mean(0.001-0.042℃/yr)LST in all the seasons(highest in monsoon).The annual mean nighttime LST(0.025℃/yr)is rising significantly faster than the mean daytime LST(0.0016℃/yr),showing the presence of a“nighttime warming effect”,which possibly increases human discomfort,particularly during the warm pre-monsoon and humid monsoon season.Elevation-dependent warming(EDW)is predominant in mean daytime LST in two elevation zones,namely(i)0-3 km and(ii)above 4 km,in all seasons,except in post-monsoon.In contrast,EDW in mean nighttime LST is observed up to 3 km and above 6 km in the basin in all the seasons,excluding post-monsoon.The warming trend in LST may be attributed to rising atmospheric moisture,cloud cover,declining snow cover,and changes in land cover to non-vegetated land.However,further investigations will involve exploring the underlying factors contributing to the observed anomalies in nighttime LST,considering variables such as regional energy balance and atmospheric stability.This research contributes to an understanding of the thermal dynamics in the mountain basin,aiding in climate studies,land management,and the development of effective adaptation strategies in the IRB.
基金funded by the Ministry of Earth Sciences(MoES)under the Geochronology project[MoES/P.O.(Seismic)8(09)-Geochron/2012]。
文摘The hydro-geochemistry and isotopic variations in groundwater,coupled with sediment geochemistry,were investigated in the Middle Gangetic Plain,India,to better understand the aquifer dynamics that influence the arsenic(As)evolution and mobilization.Eighty-four groundwater samples,thirteen River water samples,and two sediment cores(33 mbgl)were studied.The samples were analyzed for major ions and trace metals,including As and stable isotopic variability(δ^(2)H,δ^(18)O,andδ^(13)C).The study area was categorized into older and younger alluvium based on existing geomorphological differences.Younger alluvium exhibits higher As enrichment in sediment and groundwater,ranging of 2.59–31.52 mg/kg and bdl to 0.62 mg/L.Groundwater samples were thermodynamically more stable with As(OH)_(3)species ranging from 88.5%to 91.4%and FeOOH from 69%to 81%,respectively.PHREEQC and mineralogical analysis suggested goethite and siderite act as a source and sink for As.However,statistical analysis suggested reductive dissolution as the primary mechanism for As mobilization in the study area.Spatio-temporal analysis revealed elevated concentrations of As in the central and northeastern regions of the study area.Stable isotope(δ^(2)H andδ^(18)O)analysis inferred active recharge conditions primarily driven by precipitation.The depleted d-excess value and enrichedδ^(18)O in the groundwater of younger alluvium indicate the effect of groundwater recharge with significant evaporation enrichment.Groundwater recharge potentially decreased the quantity of arsenic in groundwater,whereas evaporation enrichment increased it.Rainwater infiltration during recharge introduces oxygenated water into the aquifer,leading to changes in the redox conditions and facilitating biogeochemical reactions.The carbon isotope(δ^(13)C)results suggest that high microbial activity in younger alluvium promotes As leaching from sediment into the groundwater.
文摘The energy transition challenges faced by modern civilization have significantly enhanced the demand for critical metals like lithium resulting in improved methods to explore,extract,and utilize these metals.In this comprehensive review,we discuss the different types of lithium resources,factors,and mechanisms controlling lithium enrichment in various geological settings including terrestrial and marine environments.Diverse exploration strategies including geological,geophysical,mineralogical,geochemical,and remote sensing techniques including drone-based techniques for lithium exploration studies in different terranes are summarized.An overview of the mining techniques,including beneficiation and extraction,and their principles,mechanisms,operations,and comparison of the various approaches and compatibility with different types of lithium deposits for obtaining maximum yield are evaluated.Lithium isotopic studies are useful in understanding geological processes such as past weathering events and riverine input into the oceans,as well as in understanding the source of lithium in diverse types of deposits.We also highlight the recent developments in other areas such as recycling,environmental impact,and state-of-the-art analytical techniques for determining lithium in different lithium ore deposits and other geological materials.Our overview provides the latest developments and insights in the various sectors related to lithium and prompt further developments to meet the growing demand for this valuable metal as the world transforms to clean energy.
文摘Chemometric techniques and pollution assessment indices were applied to determine the source and intensity of pollution in the Sirsa River, Himachal Pradesh,India. Results show EC, Cr, Fe, Mn, and Ni were above the permissible limit as per the Bureau of Indian Standards.The heavy metal pollution index(HPI) and contamination index(Cd) provided contrasting outcome and poor correlation was observed. A heavy metal evaluation index(HEI)method was developed using a multiple of the mean and correlation coefficient values to provide an alternative pollution classification. The criteria of HEI adopted for reclassification of HPI and Cdproduced comparable results; 40 % samples were labeled as low contamination,50 % as medium contamination, and 10 % as high contamination for all indices. Principal component analysis along with cluster analysis was used to identify the main factors responsible for degradation of water quality,namely discharge of industrial effluent, river bed mining,agricultural runoff, and minor natural or geogenic input.The methods and chemometric study proposed here can be used as effective tools to gather information about water quality and water resource management.
文摘The present study focused on the hydrochemistry of groundwater in parts of Chandauli-Varanasi region to assess the quality of groundwater for determining its suitability for drinking and agricultural purposes. Urbanization and agriculture activities have a lot of impacts on the groundwater quality of the study area. A total of 70 ground water samples were collected randomly from different sources viz. hand pump, dug wells and bore wells, and analyzed for major cations and anions. The domination of cations and anions was in the order of Na > Ca > Mg > K and HCO3 > Cl > SO4 > NO3 > F. The Piper classification for hydrogeochemical facies indicates that alkaline earth exceeds alkalis and weak acids exceed strong acid. Water quality index rating was calculated to quantify overall water quality for human consumption. Out of 70 groundwater samples, 7% and 10% samples exhibit water unsuitable for drinking purposes in pre- and post-monsoon, respectively, due to effective leaching of ions, direct discharge of domestic effluents and agricultural activities. Residual sodium carbonate values revealed that 6% sample is not suitable for irrigation purposes in both the seasons due to low permeability of the soil. The calculated values of PI indicate that the water for irrigation uses is excellent to good quality in both seasons. As per Wilcox’s diagram and US salinity laboratory classification, most of the groundwater samples are suitable for irrigation except one sample which is unsuitable for irrigation purposes. The overall quality of groundwater in post-monsoon season in all chemical constituents is on the higher side due to dissolution of surface pollutants during the infiltration and percolation of rainwater at few places due to agricultural and domestic activities.
文摘This study was conducted to investigate the dissipation pattern and runoff of herbicides to the river basin from the paddy fields. Pesticide paddy field model(PADDY) was applied to predict herbicide concentration in paddy fields. A field study was conducted in a paddy farm of Higashi Hiroshima City, Hiroshima Prefecture, Japan in the year of 2003 paddy season. The herbicides were mefenacet, thiobencarb, and bensulfuron methyl. The sample water was analyzed by using gas chromatography and HPLC after solid phase extraction. Predicted dissipation rate of thiobencarb in paddy water was higher(DT_ 50 = 4 36) than that measured, with a lower k value(-0 069). Two weeks after application no thiobencarb was detected in the drainage channel and down stream. In the down stream, thiobencarb was detected until 3 d after application, with a range of 0 02% to 0 08% of applied herbicide. The predicted dissipation rate(k) and half-life(DT_ 50 ) of mefenacet was not significantly different from that of measured. In the drainage channel, upstream and downstream mefenacet was found during the whole study period. In downstream, the maximum concentration of mefenacet was present 0 61% of applied in the paddy field on 3DAH. The dissipation rate(k) of BSM varied from -0 0860 to -0 1059 to with half-life(DT_ 50 ) 3 5 and 2 84 d. In upstream water, no BSM was detected except trace amounts(0 01 μg/L) at 3 d after application. However, in the drainage channel 8%, 6% and 1 58% of applied BSM was present at 0, 1 and 3 d after application respectively. In the down stream, the highest concentration was 1 06%, shortly after application.
基金supported by the University Grants Commission(UGC)(Grant no.:F1-17.1/2013-14/RGNF-2013-14-STNAG-43868/(SA-III/website)and(Grant no.F.15-6(Dec.,2011)/2012(NET))。
文摘The population structure and regeneration status of Magnolia punduana Hk. f. & Th., an endemic tree species of northeast India were investigated in fragmented forests in the Jarain Hills and in adjoining areas of Meghalaya state. The population structure was discontinuous in all the fragments with the absence of individuals in higher diameter classes. The number of individuals increased with the size of the fragment patches(p < 0.004). The density of mature trees(≥5 cm dbh) was high(24–30 individuals ha-1) in the largest fragment(>105 ha). The number of seedlings and saplings were also higher in the larger fragments. Human-related disturbances had a negative impact on the species population(p<0.002). Variation in the population density in different forest patches has been attributed to fragment size, site characteristics and ongoing human disturbances. The restricted distribution of the species coupled withexploitation and habitat destruction underlines the need for its conservation.
文摘Most community forests in hill regions of northeast India have been managed by traditional local institutions for centuries and most of these institutions remain functional even today. Higher forest coverage on private and community lands as compared to government land indicates that traditional institutions effectively manage community forests in the region. The present study was conducted through a survey of literature and field work using participatory research tools viz., PRA exercises, group discussions and questionnaire interviews with key informants in northeast India. We categorized the institutions involved in conservation and management of forests into three major types: traditional, quasi-traditional and modern. Traditional institutions with hierarchal structure were found in all states and are intact and functional in the state of Meghalaya. Quasi-traditional institutions, a blend of traditional and modern institutions were prevalent in Nagaland while modern institutions have almost replaced traditional institutions in Mizoram. We recorded at least eleven types of community forests viz., group of village forest, village forest, restricted forest, sacred forest, clan forest, cemetery forest, regeneration forest, bamboo forest, recreation forest, village reserved forest and medicinal plantation in villages of three states. The tribal people, through long-term trial and error experiments, have developed an elaborate, functional and generally democratic system of conservation and management of forests and associated natural ecosystems. Several forest and natural resource management lessons can be learnt from the institutional structure and decision making system of the evolving and dynamic institutions of tribal communities of the region.
文摘Wind power is a safe form of renewable energy and is one of the most promising alternative energy sources. Worldwide, the wind power industry has been rapidly growing recently. It is crucial that the locating of new projects must address both environmental and social concerns. The Red Sea shoreline in Egypt provides excellent wind power potential sites for the Red Sea Governorate. In this study, appropriate zones for wind power farms were mapped using remotely sensed data and a GIS-based model namely Spatial Multi-Criteria Evaluation (SMCE). This model incorporated several criteria, two sets of factors and a set of constraints. First, resource factors included wind speed, elevation zones used to derive the wind power density. Second, economic factors included distances from urban areas, roads and power-lines. Third, land constraints were excluded from the evaluation. The land constraints set included land slope angles, shoreline, urban areas, protectorates airports and ecologically sensitive and historical areas. The Analytical Hierarchy Process was used to assign the criteria relative weights. The weighted criteria and constraints maps were combined in the MCE model. The model identified the zones with potential wind power energy. Such zones were found to exist along the northern parts of the Red Sea shoreline. Some of which are unsuitable due to their location within a sensitive eco-system, high slopes and/or a nearby airport. By excluding such land constrains, the model identified the most appropriate zones satisfying all assigned suitability conditions for wind farms. Ideal zones amount to 706 sq. km with suitability values ranging from 83% to 100% and highly suitable zones amount to 3781 sq. km having suitability values ranging from 66% to 83%.
文摘Distribution and enrichment of six elements (iron, zinc, copper, lead, cadmium and manganese) in surface bed sediments, collected from seventeen selected locations during pre-monsoon and postmonsoon periods, of the tropical Chottanagpur plateau river Subarnarekha along with the ecological risks involved were investigated. Owing to the rich occurrence of mineral resources, the Subarnarekha river basin has a large scale presence of industrial and mining units especially in the Indian State of Jharkhand. An assessment, which involved examining distribution pattern of elements, comparative studies with sediment quality guidelines (SQGs) and geochemical background values and a sequential and integrated index analyses approach (containing contamination factor (CF), pollution load index (PLI), contamination degree (CD), enrichment factor (EF), geo-accumulation index (Igeo) and potential ecological risk index (PERI)), was followed to estimate enrichment and risks of elements in the bed sediments. Sediments collected from areas having abundance of population, industrial conglomerates and mining units recorded elevated element concentrations, which exceeded SQGs, and significantly higher values of CF, CD, PLI, EF, Igeo and PERI. Cadmium demonstrated surprising regularity in its enrichment;contributed most to the ecological risks;and high toxicity risks due to cadmium exceeded 64% of the sites. Moreover, chronic exposures of other elements would also lead to similar ecological risks. In addition to revealing potential ecological risks due to cadmium and other elements our investigation markedly highlighted anthropogenic control over sediment quality deterioration and some immediate sediment quality management strategies are needed to remediate and control river bed contamination.