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Journal of Environmental Sciences 2018年第8期30卷 87-96页

作者： Ahmed AlSayed Ahmed Fergala Ahmed Eldyasti Department of Civil Engineering Lassonde School of Engineering York University

Methanotrophic based process can be the remedy to offset the wastewater treatment facilities increasing energy requirements due to methanotroph＇s unique ability to integrate methane assimilation with multiple biotechnological applications like biological nitrogen removal and methanol production. Regardless of the methanotrophic process end product, the challenge to maintain stable microbial growth in the methanotrophs cultivation bioreactor at higher cell densities is one of the major obstacles facing the process upscaling. Therefore, a series of consecutive batch tests were performed to attentively investigate the biomass density influence on type I methanotrophs bacterial growth. In addition, food to microorganisms（F/M）, carbon to nitrogen（C/N） and nitrogen to microorganisms（N/M） ratio effect on the microbial activity was studied for the first time. It was clarified that the F/M ratio is the most influencing factor on the microbial growth at higher biomass densities rather than the biomass density increase, whereas C/N and N/M ratio change, while using nitrate as the nitrogen source,does not influence methanotrophs microbial growth. These study results would facilitate the scaling up of methanotrophic based biotechnology by identifying that F/M ratio as the key parameter that influences methanotrophs cultivation at high biomass densities.

关键词： Methanotrophs Wastewater treatment Food to microorganisms ratio biomass density

Forest biomass density,utilization and production dynamics in a western Himalayan watershed

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Journal of Forestry Research 2008年第3期19卷 171-180页

作者： Rakesh Kumar Sharma Prem Lall Sankhayan Ole Hofstad Department of Ecology and Natural Resource Management Norwegian University of life Sciences

There is enough evidence to show that the forest biomass has decreased significantly in the Indian Himalayan state of Himachal Pradesh. The government has responded through restrictive measures to check this decline. Using tree biomass as proxy for degradation, we assessed the current state of biomass within dominant land use types and examined its implications for sustainability. The highest above-ground mean tree biomass density of 1158 t·ha-1 was recorded for the reserved forest followed by 728, 13, 11, 8, 5 and 3 t·ha-1in the protected forest, fallow land, cultivated-unirrigated land, grassland, orchard land and cultivated-irrigated land respectively. Of the total ac- cessible biomass, only 0.31% was extracted annually by the local people for fuel, fodder and other uses. Though, the current level of ex- traction may be sustainable in the short run, insufficient regeneration is observed for long term sustainability. Forest biomass production was simulated for the next 30 years with a logistic growth model and the relative significance of input variables in influencing system be- haviour was analysed through sensitivity analysis. The model results highlighted the declining forest resources in the long run. Positive response through appropriate government policies can, however, change the scenario for the better.

关键词： biomass density Carrying capacity Forest degradation Fuel wood Himachal Pradesh Mean annual increment

Fire-induced carbon emissions from tropical mixed broad-leaved forests of the Terai–Siwalik region,central Nepal

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Journal of Forestry Research 2021年第6期32卷 2557-2565页

作者： Krishna Bahadur Bhujel Rejina Maskey Byanju Ambika PGautam Ramesh Prasad Sapkota Udhab Raj Khadka Central Department of Environmental Science Tribhuvan UniversityKathmanduNepal Kathmandu Forestry College Tribhuvan UniversityKathmanduNepal

Forest fires are one of the major environmental issues *** Nepal,substantial amounts of forest biomass and carbon are lost due to ***’s high value lowland forests are particularly vulnerable to ***,there are limited studies on the estimation of biomass loss and carbon emissions due to ***,this research addresses the information gap in the tropical mixed broad-leaved forests of Nawalparasi *** forests were divided into three strata:Lower Tropical Sal Mixed Broad-leaved Forest,Hill Sal Forest and Riverine Forest,and from these four community-managed forests were selected for estimating above ground ***-two sample plots were set out for above ground biomass estimation in burnt and non-burnt *** fire incidences from 2001 to 2017 were acquired from the MODIS fire *** biomass and carbon emissions were estimated using standard allometric *** fuel fraction consumed during the fire was estimated through field surveys during the forest fire *** results show that every year,over 3158 ha of forests are burnt,resulting in some 1108 tons of carbon emissions,equivalent to approximately 4066 t CO_(2),2581 t CO and 1474 t *** the forests,the Hill Sal Forest was more vulnerable to *** management strategies,therefore,should include construction of fire lines and conservation ponds along with capacity building and raising awareness among local communities and stakeholders.

关键词： Atmosphere biomass density Burnt area Carbon emission Greenhouse gases

Carbon Sequestration Effects of Shrublands in Three-North Shelterbelt Forest Region, China

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Chinese Geographical Science 2014年第4期24卷 444-453页

作者： LIU Wenhui ZHU Jiaojun JIA Quanquan ZHENG Xiao LI Junsheng LOU Xuedong HU Lile State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Institute of Applied Ecology Chinese Academy of Sciences Key Laboratory of Forest Cultivation Department of Forest Sciences Beijing Forestry University

Three-North Shelterbelt Forest （TSF） program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region is important for understanding the overall function of carbon sequestration of the forest and other terrestrial ecosystems in China. This study investigated the distribution area of shrubland in the TSF region based on remote sensing images in 1978 and 2008, and calculated the carbon density of shrubland in combination with the field investigation and previous data from published papers. The carbon sequestration quantity and rate from 1978 to 2008 was analyzed for four sub-regions and different types of shrubs in the TSF region. The results revealed that： 1） The area of shrubland in the study area and its four sub-regions increased during the past thirty years. The area of shrubland for the whole region in 2008 was 1.2 × 10^7 ha, 72.8% larger than that in 1978. The Inner Mongolia-Xinjiang Sub-region was the largest shrubland distribution area, while the highest coverage rate was found in the North China Sub-region. 2） In decreasing order of their carbon sequestration, the four types of shrubs considered in this study were Hippophae rhamnoides, Caragana spp., Haloxylon ammodendron and Vitex negundo vat. heterophylla. The carbon sequestration of/-/, rhamnoides, with a maximum mean carbon density of 16.5 Mg C/ha, was significantly higher than that of the other three species. 3） The total carbon sequestration of shrubland in the study region was 4.5 x 107 Mg C with a mean annual carbon sequestration of 1.5× 10^6 Mg C. The carbon density in the four sub-regions decreased in the following order： the Loess Plateau Sub-region, the North China Sub-region, the Northeast China Sub-region and the Inner Mongolia-Xinjiang Sub-region. The paucity of studies and data availability on the large-scale carbon sequestration of shrub species suggests this study provides a base

关键词： biomass biomass density carbon density carbon sequestration carbon sequestration rate carbon storage Three-NorthShelterbelt Forest (TSF)

Estimating and mapping forest biomass in northeast China using joint forest resources inventory and remote sensing data

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Journal of Forestry Research 2018年第3期29卷 789-803页

作者： Xinchuang Wang Shidong Wang Limin Dai Henan Polytechnic University Jiaozuo 454000People’s Republic of China State Key Laboratory of Forest and Soil Ecology Institute of Applied EcologyChinese Academy of SciencesShenyang 110164People’s Republic of China

Being able to accurately estimate and map forest biomass at large scales is important for a better understanding of the terrestrial carbon cycle and for improving the effectiveness of forest management. In this study, forest plot sample data, forest resources inventory(FRI) data, and SPOT Vegetation(SPOT-VGT) normalized difference vegetation index(NDVI) data were used to estimate total forest biomass and spatial distribution of forest biomass in northeast China(with 1 km resolution). Total forest biomass at both county and provincial scales was estimated using FRI data of 11 different forest types obtained by sampling 1156 forest plots, and newly-created volume to biomass conversion models. The biomass density at the county scale and SPOT-VGT NDVI data were used to estimate the spatial distribution of forest biomass. The results suggest that the total forest biomass was 2.4 Pg(1 Pg = 10g), with an average of 77.2 Mg ha, during the study period. Forests having greater biomass density were located in the middle mountain ranges in the study area. Human activities affected forest biomass at different elevations, slopes and aspects. The results suggest that the volume to biomass conversion models that could be developed using more plot samples and more detailed forest type classifications would be better suited for the study area and would provide more accurate biomass estimates. Use of both FRI and remote sensing data allowed the down-scaling of regional forest biomass statistics to forest cover pixels to produce a relatively fineresolution biomass map.

关键词： Forest biomass biomass density Spatial distribution Human disturbance Remote sensing

Aboveground Blue Carbon Stock Assessment of Bakhawan Eco-Park Mangrove Plantation in New Buswang, Kalibo, Aklan, the Philippines

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Open Journal of Ecology 2022年第12期12卷 773-787页

作者： Melba L. Raga-as Raffy L. Tano Floramae Q. Polaron Roberto L. Saladar Nenia N. Bohulano Jea-Ann A. Morales Eric R. Gregorio Jose Adonis N. Nacionales Forestry Department College of Agriculture Forestry and Environmental Sciences Aklan State University Banga The Philippines Agriculture Department College of Agriculture Forestry and Environmental Sciences Aklan State University Banga The Philippines Forestry Department College of Agriculture Forestry and Food Science University of Antique Hamtic The Philippines

The purpose of this study was to determine the aboveground biomass density, blue carbon stock, and monetary value of the mangroves at Bakhawan Eco-Park Mangrove Plantation in New Buswang, Kalibo, Aklan. There were 21, 45 × 45-meter sampled plots established, equivalent to 5% sampling intensity of the plantation’s total area. The number of sample plots was distributed in proportion to the area of the plantation in the specific year it was established. The quadrant and random sampling methods were used. All trees in a quadrant were identified, and the biomass density was calculated using the wood density of various mangrove species. Carbon stock was calculated by multiplying the biomass density by 0.46 or 0.5. The monetary value of C was calculated using the benefits transfer method at $5/ton. The results showed that the plantation established in 1990 had the highest biomass density (Mg/ha) and carbon stock (Mg/ha) with 132 Mg/ha and 66.02 Mg/ha, while the plantation established in 2015 had the lowest biomass density and carbon stock (Mg/ha) with 69.98 Mg/ha and 34.99 Mg/ha. Overall, the estimated total monetary value of Bakhawan Eco-Park of 250 hectares mangrove plantation in New Buswang, Kalibo, Aklan is PhP 2994771.63.

关键词： biomass density Monetary Value Mangrove Species GSP Device KASAMA