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Impact of forest governance and enforcement on deforestation and forest degradation at the district level:A study in West Bengal State,India
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作者 Aishwarya BASU Jyotish Prakash BASU 《Regional Sustainability》 2023年第4期441-452,共12页
According to the United Nations Environmental Programme(UNEP),the world loses 1.0×106hm2forest land through deforestation annually.About 1.6×106people who depend on forests for livelihood are negatively affe... According to the United Nations Environmental Programme(UNEP),the world loses 1.0×106hm2forest land through deforestation annually.About 1.6×106people who depend on forests for livelihood are negatively affected by deforestation and forest degradation.The paper attempts to study the impact of forest governance,enforcement and socio-economic factors on deforestation and forest degradation at the local level in West Bengal State,India.The study was based on questionnaire survey data during 2020–2021 collected from three western districts(Purulia,Bankura,and Paschim Medinipur)where deforestation and poverty rates are higher than other districts in West Bengal State.The total number of selected villages was 29,and the total sample households were 693.A stratified random sampling technique was used to collect data,and a questionnaire was followed.Forest governance and enforcement indices were constructed using United Nation Development Programme(UNDP)methodology and a step-wise logistic regression model was used to identify the factors affecting deforestation and forest degradation.The result of this study showed that four factors(illegal logging,weak forest administration,encroachment,and poverty)are identified for the causes of deforestation and forest degradation.It is observed that six indices of forest governance(rule of law,transparency,accountability,participation,inclusiveness and equitability,and efficiency and effectiveness)are relatively high in Purulia District.Moreover,this study shows that Purulia and Bankura districts follow medium forest governance,while Paschim Medinipur District has poor forest governance.The enforcement index is found to be highest in Purulia District(0.717)and lowest for Paschim Medinipur District(0.257).Finally,weak forest governance,poor socio-economic conditions of the households,and weak enforcement lead to the deforestation and forest degradation in the study area.Therefore,governments should strengthen law enforcement and encourage sustainable forest certification schemes to combat illegal logging. 展开更多
关键词 DEforestation Forest degradation Forest governance index Enforcement index Illegal logging Logistic regression model INDIA
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Estimating Tree Canopy Cover and Identifying Deforestation Patterns in Meghalaya (1990-2021) through ML Classifiers
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作者 Tapan Dhar Sengalvarayan Aravindan Basudeb Bhatta 《Journal of Geographic Information System》 2023年第3期309-333,共25页
This study utilizes ML classifiers to estimate canopy density based on three decades of data (1990-2021). The Support Vector Machine (SVM) classifier outperformed other classifiers, such as Random Tree and Maximum Lik... This study utilizes ML classifiers to estimate canopy density based on three decades of data (1990-2021). The Support Vector Machine (SVM) classifier outperformed other classifiers, such as Random Tree and Maximum Likelihood. Satellite data from Landsat and Sentinel 2 was classified using a developed python model, providing an economical and time-saving approach. The accuracy of the classification was evaluated through a confusion matrix and area computation. The findings indicate a negative trend in the overall decadal change, with significant tree loss attributed to jhum cultivation, mining, and quarry activities. However, positive changes were observed in recent years due to the ban on illegal mining. The study highlights the dynamic nature of tree cover and emphasizes the need for biennial assessments using at least five time-series data. Micro-level analysis in Shallang, West Khasi hills, revealed a concerning trend of shortening jhum cycles. Automation in canopy change analysis is crucial for effective forest monitoring, providing timely information for law enforcement proposals and involving forest managers, stakeholders, and watchdog organizations. 展开更多
关键词 MEGHALAYA Forest Cover ML SVM Python Script Decadal Change Biennial Change
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A system dynamics model for billion trees tsunami afforestation project of Khyber Pakhtunkhwa in Pakistan:Model application to afforestation activities 被引量:1
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作者 Naila NAZIR Aqsa FAROOQ +1 位作者 Sajjad AHMAD JAN Aftab AHMAD 《Journal of Mountain Science》 SCIE CSCD 2019年第11期2640-2653,共14页
As part of the global effort to plant billion trees,an afforestation project is launched in Pakistan in Khyber Pakhtunkhwa(KP)province to conserve existing forests and to increase area under forest cover.The present s... As part of the global effort to plant billion trees,an afforestation project is launched in Pakistan in Khyber Pakhtunkhwa(KP)province to conserve existing forests and to increase area under forest cover.The present study is designed to build a Systems'model by incorporating major activities of the Billion Tree Tsunami Afforestation Project(BTTAP)with special focus on afforestation activities to estimate the growth in forest area of KP.Availability of complete dataset was a challenge.To fix the model,the raw data taken from the project office has been utilized.Planning Commission Form 1-Phase I&II helped us with additional information.We relied on the data available for one and half period of the project as rest of the data is subject to the completion of the project.Our results show that the project target to enhance area under forest differs from the target to afforest area under the project.The system dynamics'model projection shows that the forest area of KP would be 23.59 million hectares at the end of the BTTA project,thus having an increase of 3.29%instead of 2%that has been initially proposed.However,the results show that the progress to meet the target in some afforestation classes is slow as compared to other categories.Farm forestry,plantation on communal lands and owners'plantation need special focus of the authority.Deforestation would affect 0.02 million hectares area of the project.The model under study may be used as a reference model that can be replicated to other areas where billion tree campaigns are going on. 展开更多
关键词 Billion trees PROJECT AFforestation System dynamic model FOREST area DEforestation Pakistan
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SITE CLASSIFICATION FOR PROTECTIVE FOREST AFFORESTATION ON THE COAST OF CHINA
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作者 Lin WendiNanjing Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1993年第2期18-32,共15页
Land for protective forest on the coast has special site conditions, and site classification is the scientific basis for seaboard afforestation. The site classification system on the coast zone and islands of China ma... Land for protective forest on the coast has special site conditions, and site classification is the scientific basis for seaboard afforestation. The site classification system on the coast zone and islands of China may be classified into five levels-site region (sub - region), district, class, group, and type. The land division for afforestation is carried out by the principle of enviornmental heterogeneity among regions, sub-region and district on large scale, according to the difference of air temperature, moisture and type of coast geomorphy. It may be classified into 7 regions, 12 sub-regions and 55 districts. The medium and small scaled division for site class, group and type, subdivided in a site district, are based on medium topography, topographic climate, micro - relief and soil conditions. 展开更多
关键词 Seaboard afforestation Coastal zone afforestation Site classification Coastal protective forest
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Assessment of Drivers of Deforestation and Forest Degradation in Phnom Tbeng Forest Based on Socio-Economic Surveys 被引量:2
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作者 Somanta Chan Nophea Sasaki 《Journal of Environmental Protection》 2014年第17期1641-1653,共13页
Carbon emission reductions through reducing deforestation and forest degradation or REDD+ scheme of the United Nations Framework Convention on Climate Change could not be achieved without understanding the drivers of ... Carbon emission reductions through reducing deforestation and forest degradation or REDD+ scheme of the United Nations Framework Convention on Climate Change could not be achieved without understanding the drivers of deforestation and forest degradation. Until recently, only a handful of study has focused on such drivers. Cambodia experienced rapid deforestation and forest degradation despite growing international interests in protecting forests for carbon revenue generation. This paper was designed to assess livelihood of forest-dependent community and drivers of deforestation and forest degradation in Cambodia. Quantitative and qualitative methods were used to collect socio-economic data from 42 households living in Phnom Tbeng forest, where annual deforestation rate was about 2.4% between 2004 and 2009. Our results suggest that local people depend on forests for income generation, subsistence use and social identity. About 90% of the respondents believed that deforestation was resulted from illegal logging, slush and burn agricultural practices, land clearing for large plantation, land encroachment, firewood extraction, charcoal production and forest fire. As the population has increased rapidly and almost 100% of local people depend on fuelwood for cooking, fuelwood collection will continue to cause deforestation and forest degradation unless alternative sources of affordable energy are provided. Appropriate policy interventions should be proposed to reduce the drivers obtained in this study because if drivers cannot be reduced, it is not possible to reduce deforestation and forest degradation, and related carbon emissions. 展开更多
关键词 DEforestation FOREST Degradation FUELWOOD Collection POVERTY REDD+
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The Extent and Drivers of Deforestation and Forest Degradation in Masito-Ugalla Ecosystem, Kigoma Region, Tanzania 被引量:2
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作者 John E. Makunga Salome B. Misana 《Open Journal of Forestry》 2017年第2期285-305,共21页
Deforestation and forest degradation has been observed to be rampant in Masito-Ugalla ecosystem, Kigoma Region, western part of Tanzania. This paper therefore, intended to assess the extent of deforestation and forest... Deforestation and forest degradation has been observed to be rampant in Masito-Ugalla ecosystem, Kigoma Region, western part of Tanzania. This paper therefore, intended to assess the extent of deforestation and forest degradation in the area, and to determine their causes. A total of 101 respondents were considered as the sample size for this study. The methods used for data collection were household questionnaire interviews, in-depth interviews, focus group discussions, analysis of satellite images and direct observation. The findings indicated that deforestation was occurring in the study area. Satellite data revealed diminished closed woodland, bushed grassland, forest and thickets between 1990 and 2014. On the contrary, settlement area, cultivated land and open woodland had increased during the same time frame. Proximate factors causing deforestation and forest degradation included agricultural expansion, wood extraction and expansion of settlement area. Underlying factors included population growth, poverty, poor levels of education, lack of employment, corruption and embezzlement of public funds by politicians and senior government officials;and high demand for fuel-wood. Biophysical drivers like incidences of unplanned wildfires and socio trigger events notably civil strife were also important. In order to minimize the problem and based on the factors augmenting deforestation and forest degradation in the Masito-Ugalla ecosystem and their coupled negative consequences, effective environmental conservation education, increased patrols, effective law enforcement and provision of alternative energy sources are necessary. 展开更多
关键词 DEforestation FOREST DEGRADATION DRIVERS of DEforestation Masito-Ugalla ECOSYSTEM
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Livelihood Economic Activities Causing Deforestation in Northern Ghana: Evidence of Sissala West District 被引量:1
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作者 Clifford James Fagariba Shaoxian Song Serge K. G. Soule 《Open Journal of Ecology》 2018年第1期57-74,共18页
Policymakers and international organizations are making the conscious effort to address climate change through afforestation and sustainable ecosystem management. Economic activities including agriculture, mining, and... Policymakers and international organizations are making the conscious effort to address climate change through afforestation and sustainable ecosystem management. Economic activities including agriculture, mining, and infra-structure improvement to meet basic human needs continuously degrade the natural and forest resources. The rate of deforestation in Ghana is alarming due to over-reliance on forest resources by forest-dependent communities. Perceived causes of deforestation differ from individuals and groups perspec-tive. This depends on factors including environmental knowledge, education level, market demand and socio-economic activities. Simple random sampling and key informant interview with the aid of semi-structured questionnaire was used to elicit information from the indigenes of Sissala West District to determine their perceptions of causes of deforestation. The study indicated that poverty, high illiteracy, population growth and lack of alternative source of livelihood were the indirect causes which trigger livelihood economic activities such as farming, charcoal burning, wood logging and hunting leading to degradation of the ecosystem. It was also realized that majority of the indigenes are uneducated and this contributes to their unawareness of rate of de-forestation. Recommendations suggested to address challenges were enforce-ment of bye-laws and stringent government environmental policies to deter people from degrading the forest. Education, agroforestry, afforestation, and provision of alternative livelihood were also good interventions suggested. 展开更多
关键词 DEforestation LIVELIHOOD Activities UNDERLYING CAUSES Forest COMMUNITIES
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Effects of deforestation on microbial diversity in a Siberian larch(Larix sibirica) stand in Mongolia
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作者 Jun Won Kang Yeong Dae Park 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第5期1885-1893,共9页
For evaluating microbial community changes in a Siberian larch stand disturbed by forest fire or clearcutting,357 clones were randomly selected and sequenced using a culture-independent approach and 16S rRNA sequencin... For evaluating microbial community changes in a Siberian larch stand disturbed by forest fire or clearcutting,357 clones were randomly selected and sequenced using a culture-independent approach and 16S rRNA sequencing to characterize the bacterial composition and diversity from the different disturbed Siberian larch stands.Interestingly,the burned larch stand had an increase in the relative amounts of b-proteobacteria and Firmicutes and a decrease in Acidobacteria,while Gemmatimonadetes increased Verrucomicrobia decreased in the harvested larch stand.Microbial diversity and richness were higher in the undisturbed larch stand than the disturbed(burned or clear-cut)larch stands,and the influence of clear-cutting was more negative than that of the forest fire.This study indicates that evaluating the microbial diversity of undisturbed,burned,and clear-cutting Siberian larch stands provides information about the impact of forest disturbances on soil microbial communities,which may be helpful for understanding and evaluating soil health and devising reafforestation strategies for larch. 展开更多
关键词 FOREST fire FOREST health HARVEST Microbial diversity Reafforestation Siberian Larch(Larix sibirica) Soil MICROBIOME
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Assessment of causes and future deforestation in the mountainous tropical forest of Timor Island, Indonesia
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作者 PUJIONO Eko SADONO Ronggo +1 位作者 HARTONO IMRON Muhammad Ali 《Journal of Mountain Science》 SCIE CSCD 2019年第10期2215-2231,共17页
The Mutis-Timau Forest Complex,one of the remaining mountainous tropical forest areas in Timor Island,eastern Indonesia that covers an area of 31,984 ha,tends to decrease gradually.Efforts to secure mountain forest fu... The Mutis-Timau Forest Complex,one of the remaining mountainous tropical forest areas in Timor Island,eastern Indonesia that covers an area of 31,984 ha,tends to decrease gradually.Efforts to secure mountain forest functions and counteract the negative impact of declining forest areas are often constrained by data uncertainty on factors contributing to deforestation.For this reason,this study attempts to develop models of deforestation and predict future deforestation in the Mutis-Timau Forest Complex.We constructed models of deforestation that describe the relationship between deforestation and factors contributing to deforestation using spatial statistical models.In this model,we used the deforestation data for the 1987-2017 period obtained from a previous study as dependent variables and the potential causes of deforestation generated from Geographic Information System spatial analysis as independent variables.Using the probability of deforestation derived from the model,we predicted future deforestation under two different scenarios,namely,business-as-usual(as the reference scenario)and reducing emission fromdeforestation and forest degradation.Our findings showed that a positive relationship exists between probability of deforestation,distance to the settlement,and population density variables,whereas a negative relationship exists between likelihood of deforestation,elevation,slope,distance to the road,distance to the savanna,and forest management unit variables.During the 2017-2030 period,under the business-as-usual scenario,the Mutis-Timau Forest Complex will lose 1327.65 ha in forest area with an annual deforestation rate of 0.54%.Meanwhile,under the reducing emission from deforestation and forest degradation scenario,the overall forest loss was estimated to be 1237.11 ha with an annual deforestation rate of 0.50%.The predicted area of avoided deforestation in 2017-2030 under the reducing emission from deforestation and forest degradation scenario was 90.54 ha.Such data and information are important for the Mutis-Timau Forest Complex authority in prioritizing actions for combating deforestation and designing appropriate forest-related policies and supporting data for reducing emission from deforestation and forest degradation programme or other incentive schemes in reducing deforestation. 展开更多
关键词 Mountainous TROPICAL FOREST DEforestation Spatial statistical model GEOGRAPHIC information system Reducing emission from DEforestation and FOREST degradation
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Impacts of forestation on the annual and seasonal water balance of a tropical catchment under climate change
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作者 Hero Marhaento Martijn J.Booij +1 位作者 Noorhadi Rahardjo Naveed Ahmed 《Forest Ecosystems》 SCIE CSCD 2021年第4期856-871,共16页
Background:This study aims to assess the effects of a forestation program and climate change on the annual and seasonal water balance of the Bogowonto catchment(597 km^(2))in Java,Indonesia.The catchment study is rare... Background:This study aims to assess the effects of a forestation program and climate change on the annual and seasonal water balance of the Bogowonto catchment(597 km^(2))in Java,Indonesia.The catchment study is rare example in Indonesia where forestation has been applied at the catchment level.However,since the forestation program has been initiated,evaluations of the program only focus on the planting area targets,while the environmental success e.g.,impacts on the hydrological processes have never been assessed.This study used a calibrated Soil and Water Assessment Tool(SWAT)model to diagnose the isolated and combined effects of forestation and climate change on five water balance components,namely streamflow(Q),evapotranspiration(ET),surface runoff(Q_(s)),lateral flow(Q_(l))and base flow(Q_(b)).Results:The results show that from 2006 to 2019,forest cover has increased from 2.7% to 12.8% of the total area,while in the same period there was an increase in the mean annual and seasonal temperature,rainfall,and streamflow.Results of SWAT simulations show that changes in the mean annual and seasonal water balance under the forestation only scenario were relatively minor,while changes were more pronounced under the climate change only scenario.Based on the combined impacts scenario,it was observed that the effects of a larger forest area on the water balance were smaller than the effects of climate change.Conclusions:Although we found that forestation program has minor impacts compared to that of climate change on the hydrological processes in the Bogowonto catchment,seasonally,forestation activity has decreased the streamflow and surface runoff during the wet season which may reduce the risk of moderate floods.However,much attention should be paid to the way how forestation may result in severe drought events during the dry season.Finally,we urge the importance of accounting for the positive and negative effects in future forestation programs. 展开更多
关键词 forestation Land use change Climate change SWAT model Water balance Bogowonto catchment
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THE ENVIRONMENTAL CHARACTERISTICS OF FOREST LAND AND THE TECHNIQUES OF REFORESTATION IN FIRED LAND IN DAXING'AN MOUNTAINS
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作者 李开隆 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第4期19-23,共5页
Analysis of nature environmental condition and evalwtion of selection and integration ofteclmiques have been carried out in Daxing’an mountains from 1987. The character of soil generaion in this area is influenced by... Analysis of nature environmental condition and evalwtion of selection and integration ofteclmiques have been carried out in Daxing’an mountains from 1987. The character of soil generaion in this area is influenced by the frigid, coniferous forest vegetation, weather, glacier and late soil formation process. Syntliesis teclmiques for high yield plantation include high seedling quality,suitable site preparation and eftbctive protectioll measures for yoimg trees. 展开更多
关键词 FOREST LAND Environmental characteristics Fired land Techniques of REforestation
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Effect of Closing Hillsides Afforestation on Population Diversity
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作者 石福臣 祖元刚 颜廷芬 《Journal of Forestry Research》 SCIE CAS CSCD 1998年第1期31-33,共3页
A logaritmic series distribution model was used to evaluate the index of population diversity (α value) inQuercus mongolica forest in Zhanguangcai Mountains, Heilongjiang, Northeastern China. The α value went up fro... A logaritmic series distribution model was used to evaluate the index of population diversity (α value) inQuercus mongolica forest in Zhanguangcai Mountains, Heilongjiang, Northeastern China. The α value went up from 1.07 to 4.46–6.98, after closing hillsides for 20 years. The spatial distribution of the α value was calculated among the hill slopes. The results were as follows: middle of hill>bottom of hill>top of hill. 展开更多
关键词 DIVERSITY Secondary forest Closing hillsides AFforestation
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Impact of site management on changes in soil carbon after afforestation:A review
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作者 SHI Jun CUI Lin-li TIAN Zhan 《Forestry Studies in China》 CAS 2010年第3期158-165,共8页
Afforestation and forest management can increase carbon stocks and account for emission reduction according to the Kyoto Protocol. Site management has important effects on the accumulation of soil carbon after affores... Afforestation and forest management can increase carbon stocks and account for emission reduction according to the Kyoto Protocol. Site management has important effects on the accumulation of soil carbon after afforestation. This review examines the effects of site management, including soil disturbance, fertilization, thinning, weed control, harvesting and controlled burning, on soil carbon dynamics in plantations, based on recent published results. Soil disturbance can enhance soil carbon losses, with whole ploughing causing the most and disking the least loss of soil carbon. The effects of fertilization and thinning on soil carbon are in- conclusive. Weed control can prevent the carbon input from above-grotmd residue and root turnover and increase soil temperature and soil erosion, which in turn reduces the amount of carbon on the soil surface. Soil carbon decreases with the increase of harvest- ing intensity and the retention of harvest residue can significantly enhance the accumulation of carbon in the soil. Controlled burning before afforestation has a short-term benefit for soil carbon, but it is not beneficial to the sequestration of soil carbon over the long term. Future studies should focus on investigating the long-term impact of site management practices, especially soil fertilization and thinning, on carbon, identifying the response of major functional pools of soil carbon to management practices, understanding the dy- namics of soil nitrogen pools and their role in long-term soil carbon sequestration, as well as quantifying soil carbon processes under different climate conditions and site management scenarios using models. 展开更多
关键词 site management soil carbon AFforestation plantation forest
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Dynamics of Deforestation and Degradation of Forests in the Democratic Republic of Congo from 1990 to 2018
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作者 Lutumba Suika Achille Kebin Zhang Christian Jonathan Kouassi Anoma 《Open Journal of Ecology》 2021年第5期451-461,共11页
Improving conditions to maintain soil fertility levels by avoiding deforestation would require an assessment of the contribution of forests to soil regeneration in complex and unpredictable farming systems involving a... Improving conditions to maintain soil fertility levels by avoiding deforestation would require an assessment of the contribution of forests to soil regeneration in complex and unpredictable farming systems involving alternating slash-and-burn farming. Results on forest cover over the period 1990-2018 indicate a net annual deforestation rate of 2.12% ± 0.07% and 0.12% annual degradation. The rate of deforestation is estimated mainly in relation to dense forests. Deforestation is the degradation that seems relatively important for DR Congo with relative population densities or the demand for agricultural land is greater which will lead to several consequences such as climate change, soil erosion, biodiversity loss, CO<sub>2</sub> emissions, and natural disasters. 展开更多
关键词 DEforestation Natural Disaster Climate Change Soil Regeneration Dense Forests
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Colonial Forest Policies and Tropical Deforestation: The Case of Cross River State, Nigeria
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作者 Oliver O. O. Enuoh Francis E. Bisong 《Open Journal of Forestry》 2015年第1期66-79,共14页
Nigeria has lost over 90% of her forest resources due to the hydra-headed and enduring problem of deforestation, hinging on timber logging, establishment of agricultural plantations in hitherto intact forest reserves,... Nigeria has lost over 90% of her forest resources due to the hydra-headed and enduring problem of deforestation, hinging on timber logging, establishment of agricultural plantations in hitherto intact forest reserves, construction of highways, mining of solid minerals, approval of taungya farming activities in forest reserves, extraction of non-timber forest products (NTFPs), and dereservation of large areas of certain forest reserves for other economic and development activities. Though colonialism was dismantled in the first half of the twentieth century, its policies on forest nationalization remain unchanged across many independent states in the tropics including Nigeria. The paper assesses the colonial forest policy underpinnings of tropical deforestation in Cross River State of Nigeria. It highlights the weaknesses of forest reservation laws and its impacts on tropical deforestation. The paper concludes by advocating a shift in forest policies in favour of property rights recognition and devolution of forest management responsibilities to forest communities. 展开更多
关键词 COLONIALISM FORESTS POLICIES DEforestation Devolution and COMMUNITIES
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Post-Planting Fertilization as a Reforestation Aid on a Sulfurous, Semiarid Surface Mine
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作者 Roger F. Walker 《Natural Resources》 2013年第2期209-219,共11页
Selected fertilizer formulations were assessed for their capacity to enhance growth and nutrition of Jeffrey pine (Pinus jeffreyi Grev. & Balf.) seedlings on an acidic and possibly toxic Sierran surface mine when ... Selected fertilizer formulations were assessed for their capacity to enhance growth and nutrition of Jeffrey pine (Pinus jeffreyi Grev. & Balf.) seedlings on an acidic and possibly toxic Sierran surface mine when applied three years after planting. In a study encompassing five growing seasons conducted on a semiarid, montane surface mine site on the eastern slope of the Sierra Nevada, seedling survival, dimensions, and volume measurements were coupled with foliar and soil analyses for macronutrients, micronutrients, and potentially phytotoxic metallic elements. Administered by broadcasting at four rates each, the formulations consisted of an organic amendment derived from municipal biosolids;a controlled release fertilizer containing urea, ammoniacal, and nitrate N sources;and two conventional fertilizers with one featuring urea as the predominant N form while the other delivered ammoniacal and nitrate forms. None of the formulations induced seedling mortality regardless of application rate, but the controlled release fertilizer and the conventional urea-based formulation were the most stimulatory overall, with intermediate rates of both proving most advantageous among those tested. Foliar analysis revealed that enhanced N and P nutrition, which was otherwise severely impacted by soil infertility, possibly along with that of K, probably accounted for most of the growth stimulation by the amendments, but an accessory role may have been attributable to reduced concentrations of potentially phytotoxic metallic elements, principally Mn but possibly including Fe, Cu, and Al, for which soil levels were all exceedingly elevated. With careful selection of formulation and application rate, post-planting broadcast fertilization can enhance growth and nutrition of Jeffrey pine on degraded substrates. These results provide a more complete understanding of the benefits that judicious fertilization can impart to young forest stands on surface mines and other harsh sites. 展开更多
关键词 REforestation FOREST Restoration Mine Reclamation FOREST FERTILIZATION FOREST Nutrition Soil Toxicity Jeffrey PINE PINUS jeffreyi
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Headwaters Deforestation for Cattle Pastures in the Andes of Colombia and Its Implications for Soils Properties and Hydrological Dynamic
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作者 Guillermo Vásquez-Velásquez 《Open Journal of Forestry》 2016年第5期337-347,共11页
Deforestation of headwater in the Andes of Colombia is a historical process that has its origins in pre-Hispanic communities and in nineteenth and twentieth centuries, intensified by settlers and farmers. These lands ... Deforestation of headwater in the Andes of Colombia is a historical process that has its origins in pre-Hispanic communities and in nineteenth and twentieth centuries, intensified by settlers and farmers. These lands have been intended mainly to pasture cattle. Soil compaction, caused by the trampling of cattle, was evaluated in soils derived from volcanic ash (Andisols), with reference to values found for variables in undisturbed natural forests in the same region. The compared parameters were bulk density (Db), total porosity (α), soil resistance to penetration (Rp) and pore size distribution, analyzed by water retention curves (WRC). The grazed soils had significant differences with respect to the natural forest reference values: Db was 53.7% higher, α was reduced by 11.0% and Rp in the first 7.5 cm of the top soil was more than double, with an average increase of 275.2 to 527.2 kPa. The analysis indicated that compacted soils had relatively uniform reduction in distribution of macro, meso and micropores. It was concluded that deforestation followed by pasture land destination in steep headwaters generates significant compaction processes that can affect the infiltration, percolation and soil water storage, which would have important hydrological implications: augmentation of surface runoff and soil erosion, decreased the base flow and increased direct runoff. For this reasons, it is considered that forest restoration of headwaters is important for the maintenance of hydrological functions of large river systems. 展开更多
关键词 Forest Influences DEforestation Soil Compaction HEADWATERS
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Modeling susceptibility to deforestation of remaining ecosystems in North Central Mexico with logistic regression 被引量:3
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作者 L.Miranda-Aragón E.J.Trevi o-Garza +4 位作者 J.Jiménez-Pérez O.A.Aguirre-Calderón M.A.González-Tagle M.Pompa-García C.A.Aguirre-Salado 《Journal of Forestry Research》 CAS CSCD 2012年第3期345-354,共10页
Determining underlying factors that foster deforestation and delineating forest areas by levels of susceptibility are of the main challenges when defining policies for forest management and planning at regional scale.... Determining underlying factors that foster deforestation and delineating forest areas by levels of susceptibility are of the main challenges when defining policies for forest management and planning at regional scale. The susceptibility to deforestation of remaining forest ecosystems (shrubland, temperate forest and rainforest) was conducted in the state of San Luis Potosi, located in north central Mexico. Spatial analysis techniques were used to detect the deforested areas in the study area during 1993-2007. Logistic regression was used to relate explana- tory variables (such as social, investment, forest production, biophysical and proximity factors) with susceptibility to deforestation to construct predictive models with two focuses: general and by biogeographical zone In all models, deforestation has positive correlation with distance to rainfed agriculture, and negative correlation with slope, distance to roads and distance to towns. Other variables were significant in some cases, but in others they had dual relationships, which varied in each biogeographi- cal zone. The results show that the remaining rainforest of Huasteca region is highly susceptible to deforestation. Both approaches show that more than 70% of the current rainforest area has high and very high levels of susceptibility to deforestation. The values represent a serious concern with global warming whether tree carbon is released to atmos- phere. However, after some considerations, encouraging forest environ- mental services appears to be the best alternative to achieve sustainableforest management. 展开更多
关键词 GIS land use change proximity factors statistical modeling ROC curve regional forest planning
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A model to estimate available timber and forest biomass and reforestation expenses in a mountainous region in Japan 被引量:2
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作者 Kazuhiro Aruga Ayami Murakami +3 位作者 Chikara Nakahata Reiko Yamaguchi Masashi Saito Kanae Kanetsuki 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第2期345-356,共12页
We developed a model to estimate supply potentials and available amounts of timber and forest biomass resources from profitable sub-compartments of thinning and final felling operations. Economic balances were estimat... We developed a model to estimate supply potentials and available amounts of timber and forest biomass resources from profitable sub-compartments of thinning and final felling operations. Economic balances were estimated while considering not only harvesting expenses but also reforestation expenses after final felling, which should be considered for sustainable forest management. Harvesting expenses were estimated based on two types of timber harvesting systems and three types of forest biomass harvesting systems in each sub-compartment. Then, the model was applied to Nasushiobara city of Tochigi prefecture, Japan. Reforestation expenses had large negative impacts on the financial balances of final felling operations. Few sub-compartments were profitable after considering reforestation expenses. Most profitable sub-compartments were those with mechanized operation systems and landing sales. These accounted for 17.19% of all sub-compartments, while only 5.75% of the sub-compartments were profitable based on their current operation systems and landing sales. Although the overall supply potentials of timber and forest biomass resources were 380,000 m3 and 210,000 Mg, respectively, and 15 times the planned harvest of coniferous tree volume of 25,000 m3year-1 and 50 times the annual demand for the woody gasification power generation of 4,000 Mg year-1 in Nasushiobara, available amounts of timber and forest biomass resources were only49,429 m3 and 33,333 Mg, which were 13.0% and 15.7% of supply potentials for landing sales with mechanized operation systems. 展开更多
关键词 forest biomass resources supply potentials available amounts economic balance GIS
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Application of site-specific biomass models to quantify spatial distribution of stocks and historical emissions from deforestation in a tropical forest ecosystem 被引量:1
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作者 Cedric A.Goussanou Sabin Guendehou +1 位作者 Achille E.Assogbadjo Brice Sinsin 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第1期205-213,共9页
Allometric equations developed for the Lama forest, located in southern Benin, West Africa, were applied to estimate carbon stocks of three vegetation types:undisturbed forest, degraded forest, and fallow. Carbon sto... Allometric equations developed for the Lama forest, located in southern Benin, West Africa, were applied to estimate carbon stocks of three vegetation types:undisturbed forest, degraded forest, and fallow. Carbon stock of the undisturbed forest was 2.7 times higher than that in the degraded forest and 3.4 times higher than that in fallow. The structure of the forest suggests that the individual species were generally concentrated in lower diameter classes. Carbon stock was positively correlated to basal area and negatively related to tree density, suggesting that trees in higher diameter classes contributed significantly to the total carbon stock. The study demonstrated that large trees constitute an important component to include in the sampling approach to achieve accurate carbon quantification in forestry. Historical emissions from deforestation that converted more than 30% of the Lama forest into cropland between the years 1946 and 1987 amounted to 260,563.17 tons of carbon per year(t CO2/year) for the biomass pool only. The study explained the application of biomass models and ground truth data to estimate reference carbon stock of forests. 展开更多
关键词 Biomass Reference level Site-specific biomass model Spatial distribution Tropical forest ecosystem
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