Reclaimed mined lands provide an excellent opportunity to sequester carbon and combat global warming. Carbon sequestration on reclaimed sites depend on age of reclamation, composition of species, geomining conditions ...Reclaimed mined lands provide an excellent opportunity to sequester carbon and combat global warming. Carbon sequestration on reclaimed sites depend on age of reclamation, composition of species, geomining conditions （soil characteristics） and prevailing climate. The aims of the present study were to calculate carbon （C）--stock of biomass of 4 years old plantation （dominated by Albizia lebbeck, Dalbergia sissoo and Bambusa arundinacea）, understorey vegetation and litter, soil organic carbon in reclaimed minesoil （RMS） and compare with reference forest site. Allometric equation was used for the estimation of biomass C stock and found 13.0 Mg C ha i （A lebbeck 7.8 Mg C ha-I, D sissoo 3.5 Mg C ha-l and B. arundincea 1.2 Mg C ha-l）, while stock of understorey vegetation was 0.98 Mg C ha-~. In RMS, C stock was 16.3 Mg C ha-1, out of which inorganic C contributed 1.7 g kg-l （8 % of total soil C）, Coal C 8.7 g kg^-1 （43 % of total soil C） and biogenic C 9.8 g kg^-1 （49 % of total soil C）. Total C stock in reclaimed site was calculated as 30.3 Mg C ha^-1（equivalent to 111 Mg CO2 ha-b. The study concluded that （i） coal C is responsible for overestimation of C stock in RMS （ii） Maximun C stock stored in aboveground biomass component and （iii） reclaimed mined lands will take approximately 17 years to reach the level of C stock of reference forest site in dry tropical climate.展开更多
The aim of this study is to assess the impact of industrial agriculture on the environment in Rwanda taking Mulindi tea plantations as a case study.Tea is one of the three major crops of Rwandan industrial agriculture...The aim of this study is to assess the impact of industrial agriculture on the environment in Rwanda taking Mulindi tea plantations as a case study.Tea is one of the three major crops of Rwandan industrial agriculture apart from coffee and pyrethrum.The results of this study show clearly the impact of tea plantations on the environment in Rwandan in all aspects.Soil samples collected in three zones展开更多
The aim of this study undertaken at Lake Muhazi in Rwanda was to determine and analyze the major elements present in water. The presence of many major elements （Al, As, Ba, C, Ca, Cu, Fe, H^＋, K, Mg, Mn, N, P, S, Si...The aim of this study undertaken at Lake Muhazi in Rwanda was to determine and analyze the major elements present in water. The presence of many major elements （Al, As, Ba, C, Ca, Cu, Fe, H^＋, K, Mg, Mn, N, P, S, Si, and Zn） was determined by spectroscopic technique. The concentrations of the elements were measured in water samples taken from three different locations of the lake from May to August 2008. The lake is polluted by water flow from mountain sides surrounding the lake. Other causes of pollution could be the use of agrochemicals in the sugar land, which surrounds the lake, and human activities near the lake. Finally, we proposed the strategies that can be applied in order to ensure good conservation of the environment and to prevent augmentation of heavy materials into the lake.展开更多
Mining and excavation activities cause massive degradation of land,leading to complete loss of soil resources,vegetation,and biodiversity.Mine spoils support invasive weeds(predominantly Lantana)which can strive in th...Mining and excavation activities cause massive degradation of land,leading to complete loss of soil resources,vegetation,and biodiversity.Mine spoils support invasive weeds(predominantly Lantana)which can strive in these harsh conditions,causing allelopathy during plantation stage of reclamation.It is hypothesised that biochar produced from invasive weeds will enhance enzymatic activity,CO_(2)flux and overall fertility of coal mine spoil.A 6-month incubation study was conducted on the effect of biochar amendment(2 and 3%,w/w)on mine spoil enzymatic activities(dehydrogenase,invertase,amylase and cellulase),respiration and coal mine spoil fertility.The study showed that biochar significantly improved dehydrogenase(83%)and cellulase activity(78%)at 3%amendment.Geometric mean of enzymatic activities increased from 1.87 in control to 4.51 at 2%and 3.25 at 3%biochar amendment.Mine spoil physio-chemical properties such as soil organic carbon(65%),cation exchange capacity(54%),bulk density(25%)and water holding capacity(19%),were improved significantly com-pared to the unamended mine spoil.Biochar amendment reduced mine spoil CO_(2)flux at 2%(2.85μmol CO_(2)m^(−2)s^(−1))and 3%(2.60μmol CO_(2)m^(−2)s^(−1))compared to control(4.92μmol CO_(2)m^(−2)s^(−1)).The cost of biochar production and application(2%,w/w)in pit plantation during reclamation is estimated to be 844 USD t ha−1(plantation density:1600 trees ha−1).On the basis of present study,biochar preparation from invasive weeds can be used for sustainable reclamation of coal mine spoil.展开更多
文摘Reclaimed mined lands provide an excellent opportunity to sequester carbon and combat global warming. Carbon sequestration on reclaimed sites depend on age of reclamation, composition of species, geomining conditions （soil characteristics） and prevailing climate. The aims of the present study were to calculate carbon （C）--stock of biomass of 4 years old plantation （dominated by Albizia lebbeck, Dalbergia sissoo and Bambusa arundinacea）, understorey vegetation and litter, soil organic carbon in reclaimed minesoil （RMS） and compare with reference forest site. Allometric equation was used for the estimation of biomass C stock and found 13.0 Mg C ha i （A lebbeck 7.8 Mg C ha-I, D sissoo 3.5 Mg C ha-l and B. arundincea 1.2 Mg C ha-l）, while stock of understorey vegetation was 0.98 Mg C ha-~. In RMS, C stock was 16.3 Mg C ha-1, out of which inorganic C contributed 1.7 g kg-l （8 % of total soil C）, Coal C 8.7 g kg^-1 （43 % of total soil C） and biogenic C 9.8 g kg^-1 （49 % of total soil C）. Total C stock in reclaimed site was calculated as 30.3 Mg C ha^-1（equivalent to 111 Mg CO2 ha-b. The study concluded that （i） coal C is responsible for overestimation of C stock in RMS （ii） Maximun C stock stored in aboveground biomass component and （iii） reclaimed mined lands will take approximately 17 years to reach the level of C stock of reference forest site in dry tropical climate.
文摘The aim of this study is to assess the impact of industrial agriculture on the environment in Rwanda taking Mulindi tea plantations as a case study.Tea is one of the three major crops of Rwandan industrial agriculture apart from coffee and pyrethrum.The results of this study show clearly the impact of tea plantations on the environment in Rwandan in all aspects.Soil samples collected in three zones
文摘The aim of this study undertaken at Lake Muhazi in Rwanda was to determine and analyze the major elements present in water. The presence of many major elements （Al, As, Ba, C, Ca, Cu, Fe, H^＋, K, Mg, Mn, N, P, S, Si, and Zn） was determined by spectroscopic technique. The concentrations of the elements were measured in water samples taken from three different locations of the lake from May to August 2008. The lake is polluted by water flow from mountain sides surrounding the lake. Other causes of pollution could be the use of agrochemicals in the sugar land, which surrounds the lake, and human activities near the lake. Finally, we proposed the strategies that can be applied in order to ensure good conservation of the environment and to prevent augmentation of heavy materials into the lake.
基金The authors would like to acknowledge IIT(ISM),Dhanbad and MHRD,Government of India for giving contingency funds for research and scholarship to the first author(17DR000426).
文摘Mining and excavation activities cause massive degradation of land,leading to complete loss of soil resources,vegetation,and biodiversity.Mine spoils support invasive weeds(predominantly Lantana)which can strive in these harsh conditions,causing allelopathy during plantation stage of reclamation.It is hypothesised that biochar produced from invasive weeds will enhance enzymatic activity,CO_(2)flux and overall fertility of coal mine spoil.A 6-month incubation study was conducted on the effect of biochar amendment(2 and 3%,w/w)on mine spoil enzymatic activities(dehydrogenase,invertase,amylase and cellulase),respiration and coal mine spoil fertility.The study showed that biochar significantly improved dehydrogenase(83%)and cellulase activity(78%)at 3%amendment.Geometric mean of enzymatic activities increased from 1.87 in control to 4.51 at 2%and 3.25 at 3%biochar amendment.Mine spoil physio-chemical properties such as soil organic carbon(65%),cation exchange capacity(54%),bulk density(25%)and water holding capacity(19%),were improved significantly com-pared to the unamended mine spoil.Biochar amendment reduced mine spoil CO_(2)flux at 2%(2.85μmol CO_(2)m^(−2)s^(−1))and 3%(2.60μmol CO_(2)m^(−2)s^(−1))compared to control(4.92μmol CO_(2)m^(−2)s^(−1)).The cost of biochar production and application(2%,w/w)in pit plantation during reclamation is estimated to be 844 USD t ha−1(plantation density:1600 trees ha−1).On the basis of present study,biochar preparation from invasive weeds can be used for sustainable reclamation of coal mine spoil.
