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Vegetation Restoration and Carbon Sink Function Evaluation of the Grain for Green Project
Ma Wei,
Wang Ping,
Liu Qiongge,
Dong Yunfei,
Sun Yujun
Issue:
Volume 9, Issue 6, December 2021
Pages:
162-169
Received:
20 October 2021
Accepted:
11 November 2021
Published:
17 November 2021
Abstract: Evaluation of the ecological process and carbon sink function of vegetation restoration is subject to afforestation activities, particularly after conversion of farmland to forests at different de-farming times. Based on the survey of sample plots ranging from 7 to 46 years in Larix olgensis plantation after returning farmland to forest, dynamic changing of vegetation restoration and carbon storage in representative region of Lesser Khingan Mountains were analyzed in the plantation. Firstly, community diversity situation was evaluated by Sorensen similarity index, Shannon-Wiener index, Peilou evenness index, Margalef richness index. Secondly, biomass of community was estimated by sampling harvest and allometric dimension analysis, and translated it to carbon storage via carbon rate. Thirdly, carbon storage quantity was conversed to the amount of CO2 fixation and O2 release according to the plant photosynthesis principle. At last, the economic benefit of CO2 and O2 were calculated through the current market price. The results showed that: (1) the ecological efficiency of the man-made communities raised as the reforested time increased, such as the number, richness and diversity index of species reached to 46, 6.443 and 1.733 respectively. Composition and biodiversity characteristics of plantation community changed significantly after reforested the cultivated land. (2) Carbon density of community, including arbor, shrub, herb and down woody material, increased over stand ages. Mean carbon density was 74.711 t·hm-2, and the carbon storage in regions of study was 106.624t, equaled to 13000.252t CO2 and 2585.938t O2. After conversion, economic benefit of 436.887 thousand RMB indicated remarkable benefits of the plantations. In conclusion, our study showed that the Grain for Green Project improved the land-use pattern, as farmland transformed to forests, aims of degenerated ecosystem restoration or reconstruction and plantations carbon sink potential development were achieved.
Abstract: Evaluation of the ecological process and carbon sink function of vegetation restoration is subject to afforestation activities, particularly after conversion of farmland to forests at different de-farming times. Based on the survey of sample plots ranging from 7 to 46 years in Larix olgensis plantation after returning farmland to forest, dynamic ch...
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Influence of Geographic Distance on the Floristic Composition of the Miombo Savannah in Unango, Northern Mozambique
Rolde Americo Matusse,
Merlindo Jacinto Manjate,
Valerio Pedro
Issue:
Volume 9, Issue 6, December 2021
Pages:
170-176
Received:
25 August 2020
Accepted:
7 September 2020
Published:
24 December 2021
Abstract: Geographic distance results in population decline, influencing species richness, diversity and distribution. The aim of this research was to evaluate the influence of geography on the floristic composition in the Miombo Savannah in Unango the northern part Mozambique. The studied area was 1.8ha, where 20 sample units of 30m * 30m were established using systematic sampling with a distance of 20m and individuals with DBH ≥ 5 cm were measured. The description of species composition and distribution was evaluated using the Importance Value Index (IVI), diversity by the Shannon Index, and the influence of geographical distance on floristic similarity by the Mantel test. In the floristic survey a total of 999 individuals were sampled, belonging to 34 species distributed in 19 families, the Shannon index was 2.6 and in terms of number of species, the Fabaceae family was the most representative in the study area. The species with the highest importance index values in the study area were Brachystegia spiciformis, Brachystegia boehmii, Uapaca kirkiana, Uapaca nitida, Julbernardia globiflora and Salix mucronata. The Mantel test was not significant, showing that the geographical distance does not influence the floristic similarity within the forest formation on a local scale, other factors may have an influence on the similarity between areas such as climate, topography and soils.
Abstract: Geographic distance results in population decline, influencing species richness, diversity and distribution. The aim of this research was to evaluate the influence of geography on the floristic composition in the Miombo Savannah in Unango the northern part Mozambique. The studied area was 1.8ha, where 20 sample units of 30m * 30m were established u...
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Impact of Resettlement Program on Forest Cover Change: The Case of Anbessa Forest, Benishangul-Gumuz Region, Ethiopia
Mekonen Hunde,
Aduwa Anjulo,
Bekele Tulu
Issue:
Volume 9, Issue 6, December 2021
Pages:
177-189
Received:
19 November 2021
Accepted:
7 December 2021
Published:
24 December 2021
Abstract: Background: Resettlement has been considered as a viable solution to the continual impoverishment of Ethiopian rural populations. But it has considerable impacts on natural resources. This study was carried out on impact of resettlement program on forest cover change the case of Anbessa forest. Methods: ArcGIS 10.5, ERDAS Imagine 2015, Landsat satellite imageries were acquired from USGS to analyze LULC for 44 years. The images of the area were categorized into five different LULC classes; namely dense forest, open forest, shrub land, agricultural land and settlement. Through simple random sampling procedure, a total of 129 households were selected from the total of 1941 households. Data were collected using questionnaires, GPS, interviews, focus group discussions and field observations and analyzed both quantitatively and qualitatively by descriptive statistics. Results: The results revealed that during the last 44 years, agricultural land (698ha to 15180ha) and settlement area (72ha to 13270ha) were increased, while dense forest, open forest and shrub land were decreased. The cause of forest cover change is directly linked with settlers as result expansion of agricultural activities, forest fire, fuel wood collection and constructional materials. Moreover, results revealed that deforestation, loss of biodiversity, hydrological impact and land degradation were the main consequences of forest cover change. Conclusions: Resettlement scheme has resulted in the depletion and dynamics of forest cover in Anbessa forest. From the current study, it was found that the area is under problem of deforestation, which calls for immediate attention from all concerned bodies.
Abstract: Background: Resettlement has been considered as a viable solution to the continual impoverishment of Ethiopian rural populations. But it has considerable impacts on natural resources. This study was carried out on impact of resettlement program on forest cover change the case of Anbessa forest. Methods: ArcGIS 10.5, ERDAS Imagine 2015, Landsat sate...
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A Mini-review on Dark-Photo Fermentation
M. N. I. Siddique,
Mohammad Momeen Ul Islam,
Nazaitul Shila Rasit,
Noraini Binti Ali,
Wan Sani Wan Nik
Issue:
Volume 9, Issue 6, December 2021
Pages:
190-192
Received:
25 November 2021
Accepted:
14 December 2021
Published:
24 December 2021
Abstract: Because of the benefits of increased hydrogen yields and greater substrate conversion efficiencies, systematic integration of dark and photo fermentation has gotten a lot of attention recently. This integration can be done in two stages sequentially or in a single stage, with the single-stage integration appearing to be more cost-effective. The primary operating techniques, key factors affecting hydrogen yields, and the overall increase in hydrogen yields realized in the single-stage integration biohydrogen processes are all thoroughly reviewed in this paper. Selection of a more complementary pair of dark and photofermentative microorganisms, optimization of common growing medium composition, and improved tactics for consistent growth pH management and lignocellulosic feedstock facilitation have been recognized as important issues that require more attention and development. Most investigations so far have been performed with batch digesters utilizing unpolluted culture and a sole wastewater, so, the method improvement of the combined two-steps procedure was yet in the early stages. The combination of dark- and photo-fermentation can be used to boost biohydrogen production and substrate utilization, making it the best option for commercial biohydrogen generation. The current status of single-stage integration bio-hydrogen technology has been reviewed, and its potential to become a reliable hydrogen production technology has been factually assessed, based on the insightful talks.
Abstract: Because of the benefits of increased hydrogen yields and greater substrate conversion efficiencies, systematic integration of dark and photo fermentation has gotten a lot of attention recently. This integration can be done in two stages sequentially or in a single stage, with the single-stage integration appearing to be more cost-effective. The pri...
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The Heavy Metal Pollution Assessment of Topsoil in the North Bank of the Yellow River in Shandong Based on Granulation
Han Danmei,
Zhu Lidong,
Ding Min,
Peng Shuzhen,
Zhao Qiuyue,
Zhang Wei
Issue:
Volume 9, Issue 6, December 2021
Pages:
193-200
Received:
25 December 2021
Accepted:
Published:
29 December 2021
Abstract: With the rapid development of the economy, environmental pollution is becoming more and more serious. As one of the important carriers of industry and agriculture, the soil is one of the key concerns of people. The research on soil heavy metal pollution is also progressing day by day, and there are abundant research results. However, there are few studies on soil heavy metal pollution based on a granular level, most of which are whole-rock samples. Therefore, we evaluated the soil heavy metal pollution in the north bank of the Yellow River in Shandong province from the perspective of grain size. We hope to fill that gap. In this study, we systematically sampled topsoil from 15 sites on the north bank of the Yellow River in Shandong province. It was divided into two components, <20μm and 20-63μm, with a total of 32 data. The contents of heavy metals in soil were determined by ICP-MS. Based on experimental data, the single factor method and comprehensive index method were used to evaluate heavy metal pollution. The results showed that heavy metal pollution conditions were related to soil particle thickness. The contents of heavy metals in fine soil <20μm were higher. Among them, the heavy metal Ni content in 15 points exceeded the safety line, and 2 areas were slightly polluted. The composite index of 16 samples exceeded the safety line, and four sites had minor contamination. The heavy metal content of the soil with 20~63μm, thick particles was generally low, and the pollution evaluation result was clean. The results verified the geochemical characteristics of heavy metals enrichment in fine soil. In addition, the potential ecological hazards of heavy metals in soil particles < 20μm and 20-63μm were evaluated. The results showed slight ecological damage, which may be related to the biological toxicity of heavy metals.
Abstract: With the rapid development of the economy, environmental pollution is becoming more and more serious. As one of the important carriers of industry and agriculture, the soil is one of the key concerns of people. The research on soil heavy metal pollution is also progressing day by day, and there are abundant research results. However, there are few ...
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Establishing Legal Force Majeure Case for the Interruption of Hydro Energy Supply Related to an Extreme Hydrological Drought Event
Petre Roman,
Diana Maria Bucur,
Georgiana Dunca
Issue:
Volume 9, Issue 6, December 2021
Pages:
201-213
Received:
26 November 2021
Accepted:
20 December 2021
Published:
29 December 2021
Abstract: The management of water resources and specifically the energy supply from hydropower systems are strongly affected by drought events. This paper is devoted to the unfolding of legal consequences caused by an extreme hydrological drought event. The legal litigation occurred when – due to a severe deficit of water – the hydropower company that manages the hydro energy resources over the entire territory of Romania was unable to deliver the amount of electricity stipulated in the power purchase agreements. The studypresents an extensive statistical analysis of extreme hydrological drought events occurrence, using the threshold level method. The statistical analysis was applied on large historical records of the flow rates (50-90 years) and revealed the occurrence of extreme drought events, i.e. extremely low occurrence frequency phenomena. The characteristics of the historical data were studied to highlight the area where the forecast normally used in the hydro generation planning is not possible. In order to evaluate the occurrence of extreme drought phenomena, the natural monthly and annually flows of the Danube and other seven major interior rivers in Romania (Argeș, Bistrița, Olt, Lotru, Sebeș, Someș, Siret and Raul Mare) were analyzed, reflecting fairly a general picture of the flow distribution on the entire territory. The analyzed cases refer to periods when – due to a severe deficit of water – the Romanian hydropower company was unable to generate electricity according to the power purchase agreements (PPA). The results of the statistical analysis were further used as the base for the legal cases that confirmed the force majeure situations claimed by the hydropower company.
Abstract: The management of water resources and specifically the energy supply from hydropower systems are strongly affected by drought events. This paper is devoted to the unfolding of legal consequences caused by an extreme hydrological drought event. The legal litigation occurred when – due to a severe deficit of water – the hydropower company that manage...
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Modeling and Forecasting Daily Temperature Time Series in the Memphis, Tennessee
Khayrun Nahar Mitu,
Khairul Hasan
Issue:
Volume 9, Issue 6, December 2021
Pages:
214-221
Received:
25 September 2021
Accepted:
2 November 2021
Published:
29 December 2021
Abstract: Temperature is an essential weather component because of its tremendous impact on humans and the environment. As a result, one of the widely researched parts of global climate change study is temperature forecasting. This work analyzes trends and forecasts a temperature change to see the transient variations over time using daily temperature data from January 1, 2016 – November 3, 2019, collected from a weather station located at the Memphis International Airport. The Mann-Kendall (M-K) test is used to detect time series analysis patterns as a non-parametric technique. The result from the test revealed that the temperature time series increased by 0.0030 °F almost every day, implying that the location is becoming hotter. The other method of analysis is the autoregressive integrated moving average (ARIMA) model, which fits temperature time series using its three standard processes of identification, diagnosis, and forecasting. Considering the selection criteria, The seasonal autoregressive integrated moving average (SARIMA) (3, 0, 0) (0, 1, 0)365 model is found as appropriate for the studied temperature data on a daily basis. Finally, the selected model is utilized to estimate the next 50 days; after November 3, 2019, the temperature forecast showed an increasing trend. This observed trend provides an understanding of daily temperature change in the studied area for that specific period.
Abstract: Temperature is an essential weather component because of its tremendous impact on humans and the environment. As a result, one of the widely researched parts of global climate change study is temperature forecasting. This work analyzes trends and forecasts a temperature change to see the transient variations over time using daily temperature data f...
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