Forest Ecological Zones Research Articles

Induced abortion among adolescent girls and young women: should geography matter in Ghana?

Globally, there has been a slight reduction in abortion rates. However, abortion rates have increased in other major regions, including sub-Saharan Africa. Induced abortion rates vary by ecological zone and place of residence, and it is prevalent among women aged 15–24. This study examined the predictors of induced abortion in ecological zones by place of residence among adolescent girls and young women aged 15–24. The 2017 Ghana Maternal and Health Survey, which is a nationally representative household survey dataset, was used for this study. This analysis is restricted to 3194 Adolescent Girls and Young Women (AGYW) aged 15–24 years. A two-level multilevel binary logistic regression model was used to analyze the individual and contextual level characteristics associated with induced abortion. The results show that the prevalence rate of induced abortion among adolescent girls and young women is 26.0%. After adjusting for individual and community level factors, ecological zones and place of residence predicted induced abortion among AGYW. More importantly, the results demonstrate that AGYW residing in urban areas of the forest zones were statistically significant to report induced abortion compared to those in the rural areas. In conclusion, there is a strong association between place of residence, ecological zones and induced abortion in Ghana. Primarily, urban-dwelling women in the forest zone are more likely to report induced abortion. There is, therefore, a need to prioritize women residing in urban areas and the forest zone of Ghana. AGYW in these high-risk ecological zones should be reached with sufficient health education and sensitization about induced abortion. Given the protective factor of contraceptive use, it is recommended that the government and its health agencies strengthen campaigns to improve contraceptive use among AGYW across the country, particularly in the urban forest ecological zone.

Analysis of spatio-temporal changes in net primary productivity and their driving factors in ecological functional areas of the Yellow River Basin

The Yellow River Basin (YRB) is an important region for both ecological and economic growth in China, and a healthy and stable ecological environment is fundamental to achieving high-quality development. Investigating the spatio-temporal changs of vegetation carbon sinks in the YRB is necessary to improve understanding of the regional carbon cycle. This study analyzed the YRB using the Google Earth Engine (GEE) platform. The basin was divided into sections based on ecological function regionalization schemes. We applied Theil-Sen median trend analysis and Spearman correlation analysis, along with the lasso regression model, to examine the NPP's temporal and spatial patterns and its driving factors in these regions. The objective was to examine the NPP’ s temporal and spatial patterns and its driving factors in these regions, identifying commonalities within regions and differences between regions, while analyzing in a targeted manner the lack of vegetation carbon sequestration in ecological areas. This study highlighted the importance of ecological engineering in ecological civilization and carbon neutrality, providing scientific theoretical support and a decision-making basis for the realization of carbon neutrality. The research results indicate significant upward trends (p<0.001) in both the average annual NPP (AANPP) growth rate (57.98%) and the total annual NPP (TANPP) growth rate (41.9%) in the YRB from 2001 to 2020. The multi-year average NPP (MYANPP) exhibit a spatial distribution with high values in the south and low values in the north. The spatial distribution of NPP exhibits notable spatial aggregation and heterogeneity, where regions demonstrating improvement trends constitute 93.01% of the area, and approximately 79.73% of this region displays low volatility. A high-value area is concentrated in the Agroecological Zone of the Fenwei Basin (I-11), the Loess Plateau Agriculture and Grassland Ecological Zone (I-12), and the Qinba Mountains Deciduous and Evergreen Broad-leaved Forest Ecological Zone (I-15), with significant spatial differences. Temperature, precipitation, and forests are the foremost elements affecting NPP in the YRB, exhibiting positive correlations. Conversely, farmland displays negative correlations. Overall, NPP shows an increasing trend in all ecological function areas, and the NPP of the YRB shows a trend of improvement as a whole, as the ecological environment of the YRB has improved significantly.

Geospatial Mapping of Malaria in the Lowland Forest Ecological Zone of Ondo State, Nigeria

Purpose: This study analyzed the spatial and temporal patterns of malaria occurrence in Ondo state, Nigeria, and to identify the major factors influencing the disease transmission and control.&#x0D; Methodology: The research collects primary data from questionnaires administered to hospital staff and workers in areas with high malaria cases while secondary data were sourced from the State’s ministry of health malaria cases gazette. The data was sorted, processed, and analyzed using Microsoft Excel and ArcGIS 10.2 software to produce maps and graphs showing the malaria occurrence and trends in the study area.&#x0D; Findings: The study analyzed the malaria occurrence and trends in Ondo State, Nigeria, from 2011 to 2018, using questionnaires and secondary data. The result revealed that mosquito, blood group, poverty, and communicability were significant factors for malaria incidence (p &lt; 0.001), while seasonality, time of day, and immunity status were non-significant (p &gt; 0.05). Result shows that malaria could be transmitted from mother to child during childbirth (p=0.008), but mortality was non-significant in the three Local Government Areas (LGAs) studied (p = 0.166). In addition, malaria cases and attack rate declined significantly from 2015 to 2018, due to the improved health facilities and preventive measures implemented by the State government and health authorities &#x0D; Unique contributor to theory, policy and practice: The study contributes to the existing knowledge and literature on malaria epidemiology and control in Nigeria, by providing a comprehensive and updated spatial and temporal analysis of the disease occurrence and factors in Ondo state. The study also provides useful recommendations for the state ministry of health and government to conduct further studies and develop strategies to interrupt malaria transmission in low susceptible settings, and to achieve the goal of malaria elimination in the state in line with global setting.

Trade-offs and synergies relationships of ecosystem services and their socio-ecological driving factors under different spatial scales in Shaoguan City, Guangdong, China.

Ecosystem services refer to the benefits that human obtain from natural ecosystems. Different ecosystem services are generated by the combination of social-ecological driving factors, and exhibit different spatial patterns across scales. The complex relationships and driving mechanisms among ecosystem services under different spatial scales remain unclear. With Shaoguan City from Guangdong Province as the study area, we analyzed the spatial patterns and relationships of four ecosystem services and their trade-offs/synergies (TOSs), quantified their responses to seven social-ecological drivers at the kilometer grid scale and sub-watershed scale, and proposed regional ecologi-cal management and planning strategies for cross-scale sustainable development. The results showed that the spatial distribution of ecosystem services in Shaoguan City exhibited spatial clustering and cross-scale variations. Habitat quality, water yield, and carbon storage exhibited similar spatial distribution pattern. High supply was mainly distributed in mountainous areas in the east, north, west, and south, while weak supply was distributed in plain areas in the central, northwest, south and northeast. In addition, the spatial clustering of these services intensified with increasing spatial scale. Ecosystem services displayed synergistic relationships at both spatial scales, and the intensity of the synergy changed with scale. At both the kilometer grid and sub-watershed scale, the primary drivers for ecosystem services were the normalized vegetation index and digital elevation model. The main driver for TOSs was the mean annual temperature at the kilometer grid scale, while it was the mean annual evapotranspiration at the sub-watershed scale. Based on the supply levels of ecosystem services, the study area could be divided into five distinct ecosystem service bundles, i.e., mountain ecological balance zone, forest ecological conservation zone, urban forest maintenance zone, ecologically sensitive zone, and ecological risk zone. All bundles exhibited both spatial heterogeneity and cross-scale variations. We integrated the cross-scale variations of four representative ecosystem services and their complex interactions and driving mechanisms in Shaoguan City into spatial planning to facilitate the sustainable ecosystem management across multiple scales, which could offer valuable references for the construction of ecological civilization in other regions.

Assessment of Weathering Intensity and Pedogenesis of Lithosequence Located in Two Agroecological Zones of Nigeria

Elemental oxides can help to identify processes of soil formation and the degree of soil development. This study assessed soil development and weathering intensity in soils developed on schist and older granite in upland tropical rain forest and southern guinea savanna agro ecological zones of Nigeria. Soil profile samples were collected in each of the study locations. In the laboratory, total elemental oxides was determined using the energy dispersing X-ray Fluorescence (EDXRF) XRF SPEC (Minipal 4). The relative intensity of weathering of total elemental oxides was determined by choosing titanium as the suitable indexing element and the relative gain or loss of element was estimated using relative retained element (Ro) equation. Result obtained, revealed that SiO2 was the most abundant in the soils. Distribution of Al2O3 and CaO showed the direction of the pedogenic age. Older granite soil had higher values of Al2O3 and lower values of CaO. There was negative relationship of SiO2 with Al2O3 and Fe2O3. The trace elemental oxides were less than 1% and zirconium oxide was the most retained oxide in the soils. Soil which developed on schist retained more of the trace elements than soil on older granite. There was evidence of alitization, ferritization and desillication in the soils. Parent materials contributed to loss and gain of trace elemental oxides. Older granite soil was more weathered and pedologically older than schist derived soils.

Yellow maize breeding for higher beta-carotene: farmers’ perceptions of Vitamin-A deficiency consequences and readiness to grow improved varieties in Ghana

Vitamin A deficiency poses serious health concerns among the Ghanaian populace, particularly children and pregnant women. The production and consumption of yellow maize, which contains pro-vitamin A carotenoids such as beta carotene, is therefore encouraged. Consequently, yellow maize consumption is fast gaining acceptance. However, in the near future comensurate increases in production must be achieved to ensure food security. In this regard, the aims of the study were to: evaluate farmer willingness to cultivate yellow maize varieties with enhanced beta carotene content, ascertain extent of farmers’ knowledge on production constraints and mitigation, and evaluate farmers’ perception on nutritional benefits of yellow maize and the effects of vitamin A deficiency. The survey was conducted between January and May 2018 and it covered four districts representing the forest and guinea savanna ecological zones in Ghana. In each district, five communities with 10 participants each were covered. Most yellow maize farmers (78 %) were between 15 and 55 years, 42.5 % of the farmers had no formal education, 29 % had secondary education and only 8 % had tertiary education. The main challenges facing yellow maize (YM) farmers were pest control and low yield due to erratic rainfall. Majority (70 %) of the farmers had heard about vitamin A deficiency and also noticed stunted growth, mental retardation and poor eye sight in their communities but did not link such symptoms to vitamin A deficiency. Most respondents (70 %) were not aware that yellow maize contains beta carotene. Majority (70 %) of the respondents opined that improvement in the beta carotene content of yellow maize will greatly help to drastically minimize vitamin A deficiency and enhance food security. The information elicited from farmers will guide future development of yellow maize varieties for improved production and nutrition. Key words: maize, vitamin-A, deficiency, beta-carotene, food security, improved variety

Drivers of willingness to pay for reforestation of urban ecosystems in Ghana

PurposePopulation growth and urbanization pose several threats to terrestrial ecosystems, especially in forest ecological zones worldwide. This study examines the drivers of average willingness to pay (WTP) to restore urban forests in a developing country.Design/methodology/approachIt utilizes survey data of households and employs a robust Heckman two-step estimator with bootstrapping to address the research objective.FindingsThe study underscores the role of income, gender, education and perception of the health benefits of forests as the underlying determinants of restoration bids by respondents. These drivers have a positive and statistically significant effect on forest restoration. Education and gender appear to be the most effective by magnitude, followed by the perception of health benefits, then income. Attention is therefore drawn to relevant economic, sociocultural and psychological factors towards the goal of forestry to improve well-being in urban centres.Originality/valueThis paper seeks to add methodological insights to the literature on reforestation and land use changes in the Accra metropolitan area and the local population’s WTP for reforestation in this area. In principle, this is a case study informing about the values people hold for forests in Ghana and Africa, where a knowledge gap exists with respect to their socio-economic valuation.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-09-2022-0618

Qualitative mutant traits within the indigenous chicken population in selected ecological zones of Ghana

A study was carried out to find out the various mutant traits present in the indigenous chicken population and their influence on egg production in the three ecological zones of Ghana. Four hundred and five (405) households were purposively selected across the Guinea Savannah, Semi-deciduous Rain Forest and Coastal Savannah ecological zones. Structured questionnaire and on-site interviews were used to obtain information from the local chicken keepers. The individual birds were phenotypically observed for the presence of the following genes; frizzle, naked neck, silkiness, polydactyl, ptilopody, crest feathered and flightless. Data on flightless chickens were not available except their gene frequencies since the respondents do not keep them for economic purposes. The data collected were organised and analysed such that phenotypic groups were considered as treatments and ecological zones as blocks. The frequency of the genes responsible for mutant traits were obtained from a count of the proportion of recessive in the sample using the Hardy Weinberg rule. The calculated gene frequencies for the mutant traits observed within the local chicken population ranged from 0.01 to 0.05 which differed significantly (p<0.05) from the expected Mendelian values of 0.75. Average clutch size per year, number of eggs set and chicks hatched per natural incubation were not significantly different (p>0.05) among the three ecological zones. The percentage hatchability for Guinea savannah and Coastal savannah were relatively higher compared to Semi-deciduous rain forest. In terms of phenotypes, polydactyl birds were significantly better (p<0.05) in average eggs per clutch per bird, number of eggs set for natural incubation and number of chicks hatched. Despite the low frequencies of these mutant birds, they had a higher potential for egg laying compared to their recessive counterparts.

Rapid invasion and expansion of the Asian longhorned tick (Haemaphysalis longicornis) into a new area on Long Island, New York, USA

Since its discovery in the United States in 2017, the Asian longhorned tick (Haemaphysalis longicornis) has been detected in most eastern states between Rhode Island and Georgia. Long Island, east of New York City, a recognized high-risk area for tick-borne diseases, is geographically close to New Jersey and New York sites where H. longicornis was originally found. However, extensive tick surveys conducted in 2018 did not identify H. longicornis on Long Island. In stark contrast, our 2022 tick survey suggests that H. longicornis has rapidly invaded and expanded in multiple surveying sites on Long Island (12 out of 17 sites). Overall, the relative abundance of H. longicornis was similar to that of lone star ticks, Amblyomma americanum, a previously recognized tick species abundantly present on Long Island. Interestingly, our survey suggests that H. longicornis has expanded within the Appalachian forest ecological zone of Long Island's north shore compared to the Pine Barrens located on the south shore of Long Island. The rapid invasion and expansion of H. longicornis into an insular environment are different from the historical invasion and expansion of two native tick species, Ixodes scapularis (blacklegged tick or deer tick) and A. americanum, in Long Island. The implications of H. longicornis transmitting or introducing tick-borne pathogens of public health importance remain unknown.

Effects of Monocropping on Land Cover Transitions in the Wet Evergreen Agro-Ecological Zone of Ghana

The wet evergreen forest ecological zone of Ghana is undergoing notable structural changes, although most maps erroneously depict the area to be an intact forest. Several hectares of plantation agriculture such as rubber, oil palm, and cocoa are replacing the natural vegetation and habitats, thereby threatening indigenous biodiversity. This study aimed to assess the effects of tree monocrop proliferation on landscape transitions between 1986 and 2020 in the Wassa East District of Ghana. The ISODATA clustering technique was used to produce land cover category maps from Landsat images of 1986, 2002, and 2020. A post-classification change detection technique resulted in transition matrices which were used for the computation of land cover transition intensities over 34 years. The results showed that the landscape was dominated by forests in 1986. Still, the forest continuously declined by 34% (1% annually) in 2020 while all other land cover types increased in both periods with cocoa covering 23% oil palm covering 14%, and rubber covering 2% of the land area. These conversions in the land area are important, especially since the closed forests usually transition to monocrops through the intermediate process: food crop farming. This information is essential for decision making on land development and biodiversity conservation.

京津冀地区生态用地稳定性格局及其影响因素分析

PDF HTML阅读 XML下载 导出引用 引用提醒 京津冀地区生态用地稳定性格局及其影响因素 DOI: 10.5846/stxb202203230719 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 中央级公益性科研院所基本科研业务费专项资金项目（CAFYBB2020ZB008） Spatial pattern of ecological land stability analysis and influencing factor in Beijing-Tianjin-Hebei Region Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:探索生态用地稳定性格局对动态背景下区域生态规划与管理具有重要意义。本文基于2000、2010、2020年京津冀地区生态用地数据基础，提取2000-2010和2010-2020年间稳定性生态用地，借鉴并应用生态用地稳定性指数予以衡量区域生态用地的时空稳定效应，并利用ArcGIS平台空间统计工具对生态用地稳定性空间格局进行分析，最后基于地理探测模型对生态用地稳定性的影响机制及其区域差异进行探索。研究结果显示，（1）2000-2010年和2010-2020年，京津冀地区稳定性生态用地有所减少，集中分布在内蒙古草原生态区和燕山-太行山山地林生态区。（2）两时期生态用地稳定性指数分别为90.85%和83.86%，呈现"西北高、东南低"。生态用地稳定性指数等级结构显示前期极低稳定性和极高稳定性面积占绝对主导，后期极低、高和极高稳定性面积共同主导。生态用地稳定性指数空间格局呈现显著冷热点效应，热点区汇集在燕山-太行山山地林生态区和内蒙古草原生态区，冷点区集中在京津唐城市生态区和华北平原生态区。（3）整体研究区高程、坡度、地貌和土壤类型等地理要素解释力较高；平原区内温度因子解释力度最为突出，地理因素和社会经济因素的解释力度也均较显著；山区内国内生产总值、人口密度、居民点密度和道路密度等社会经济因素影响作用更加突出。 Abstract:Exploring ecological land stability pattern is of great importance for regional ecological planning and management in the context of the dynamic development of urbanization. Based on the data on ecological land use in the Beijing-Tianjin-Hebei region in 2000, 2010, and 2020, we extracted the stable ecological land in 2000-2010 and 2010-2020. We used the ecological land stability index to describe the spatial and temporal dynamics of ecological land stability. At the same time, we analyzed the spatial pattern of the ecological land stability index. Finally, we utilized the geographical detection model to explore the influencing mechanism and regional differences in the ecological land stability. The results showed that:(1) the area of stable ecological land decreased in the two periods, which were more in Inner Mongolia Grassland Ecological Zone and Yan-Taihang Mountain Forest Ecological Zone. (2) Ecological land stability indexes were 90.85% and 83.86% in two periods, which were higher in the northwest and lower in the southeast. The area of the grade of stability, which is named extremely low and extremely high, was the most important from 2000 to 2010. The area of the class of stability, which is called extremely low, high, and extremely high, was similar from 2010 to 2020. The ecological land stability index had cold/hot spots. The area of the hot spots was more in Yan-Taihang Mountain Forest Ecological Zone and Inner Mongolia Grassland Ecological Zone. The area of the cold spots was more in Beingjing-Tianjin-Tangshan City Ecological Zone and North China Plain Ecological Zone. (3) In the study area, the explanation intensity of the elevation, the slope, the landform, and the soil factors was higher. In the plain area, the temperature had the highest explanatory power. The geographical and social-economic factors also had superior explanatory power; in the mountainous area, the influence of GDP, population density, settlement density, and road density was more pronounced. 参考文献 相似文献 引证文献

Estimating the spatial distribution of evapotranspiration within the Pra River Basin of Ghana

It is important in water resource planning to accurately estimate the spatial distribution of evapotranspiration (ET) as an input parameter for hydrological studies. Although, conventional pan evaporation, lysimetric and eddy covariance techniques have been used, they only estimate point values. Hence, this study aimed at estimating the spatial distribution of ET within the Pra River Basin (a forest ecological zone) of Ghana, using cloud-free Landsat 8 (OLI/TIRS) satellite images employing the SEBAL methodology. The study further estimates the spatial distribution ET in relation to major climatic variables, Land Use Land Cover (LULC) types and energy balance components. The overall spatial distribution of ET had a mean value of 5.63 mm/day. Spatial distribution of ET (mm/day) for water body (5.51–7.81) and uncultivated forest (5.10–7.71) were high, while moderately average values were observed for logged forest (4.80–7.51). Settlement and bare landscapes observed low rates ((2.05–5.10) mm/day). Spatially, ET was higher in the upper western, central and the eastern parts of the basin, but lower in the northern part and pockets of areas at the southern part of the basin where settlement/bare landscape and logged forest dominate. Areas with high temperature and high solar radiation experiences high ET, while low wind speed, low to average temperature and solar radiation areas experience low ET. Also, areas with both high net radiation and ground heat flux but low to average sensible heat flux experiences high ET and vice versa. Linear regression analysis showed good fit with slope of 0.76 and R2 of 0.93 indicating that 93 % of the variations in observed field measurement of ET fitted perfectly well with ET distributions generated by the SEBAL model.

Exploring the long-term vegetation dynamics of different ecological zones in the farming-pastoral ecotone in northern China.

The vegetation in the farming-pastoral ecotone in northern China is influenced by both natural and anthropogenic factors and has undergone drastic changes in the past decades. The farming-pastoral ecotone is the transition zone from agriculture to animal husbandry. The ecological environment of this ecotone is complex and fragile. Most researches have primarily focused on the entire farming-pastoral ecotone, seldomly considering the differences between different ecological zones characterized by soil, climate, and biome conditions. Based on the long time series of leaf area index (LAI) data, meteorological data, and land-use dataset, this study analyzed LAI variation trends, the correlations between LAI and climate factors, and the impact of land-use type change on vegetation in the farming-pastoral ecotone in northern China. Moreover, this paper makes a full study of the changes of the whole study area from the perspective of the differences between different ecological zones. The results showed that over 36years, areas with vegetation improvements were considerably larger than those with degradations. However, there were still 49.56% of the total area showing no significant vegetation change. There are differences in vegetation change and response to climate between the forest ecological zones and the grassland ecological zones. The vegetation improvement trends of the forest ecological zones were larger and more sensitive to temperature, while the vegetation improvements of the grassland ecological zones were relatively small, and were more sensitive to precipitation. Human activities promote LAI changes in areas close to the forest ecological zones. The change of land use indicates that the decrease of the overall natural vegetation area has not resulted in decreasing LAI. And there is a growing trend of woodland area in the grassland ecological zones. The study provides a theoretical basis for the management of the environment and vegetation in the farming-pastoral ecotone in northern China.

A Comparative Analysis of Bioremediation of Hydrocarbon Polluted Soil in the Island Forest Ecosystem and the Low land Forest Ecosystem in the Niger Delta through Enhanced Natural Attenuation Process (ENAP)

The Niger Delta region has witnessed environmental pollution arising from oil activities over the years of oil exploration and production. Soil fertility in both the Lowland Forest Ecological Zone and Island Forest Ecological Zone were investigated to establish the consequences of oil pollution on the soil and remedial actions to restore back quality and fertility of the soil. A suitable cost effective and environmentally friendly technology to handle the pollutions in the Niger Delta region can be found in Remediation by Enhanced Natural Attenuation Process (ENAP) which facilitates the activities of microorganisms to biodegrade the hydrocarbon impacted soil. The study compared the bio-physicochemical parameters of the oil spill polluted soil with particular reference to areas of oil production of the two Ecological Systems with those of the unaffected soil as well as their response to bioremediation interventions using ENAP. The results demonstrated significant decrease in the values of the key indicator parameter, the Total Petroleum Hydrocarbons (TPH). But for the unenhanced process, the result showed low level of reduction of TPH values for the polluted soils. A degradation trend was demonstrated with time leading to significant TPH reductions and improved key soil fertility indices. The result showed that the level of the nutrient status of soil in the region can be improved through the natural attenuation process.

Variation in the vegetation fade stage and its relationships with climate and vegetation productivity in Inner Mongolia, China

Based on the MODIS NDVI data from 2001 to 2018, we extracted the fade stage of vegetation in Inner Mongolia and the characteristics of its temporal and spatial changes using the Logistic curve maximum curvature method of the cumulative normalized difference vegetation index (NDVI). We analyzed the responses of fade stage to climatic factors and NDVI at the ecological zone level. The results showed that the fade stage in Inner Mongolia occurred between the day of year (DOY) 260 and 280 during the study period. It was DOY 270-280 in the forest ecological zone, and was delayed from the south to north. The fade stage in the grassland ecological zone was the earliest and ranged between DOY 257 and 273, and was delayed from the northeast to southwest. The fade stage in the desert ecological zone ranged between DOY 270 and 283, which was delayed from the northeast to southwest. From 2001 to 2018, the fade stage in three ecological zones showed an insignificant delaying trend. Spatially, vegetation productivity decreased from the northeast to southwest, with a larger area of an increasing temporal trend than that of a decreasing trend. The fade stage in the entire Inner Mongolia and three ecological zones was greatly affected by precipitation during the two or three months before the fade stage and was positively correlated with the pre-season average temperature, maximum temperature, and minimum temperature, respectively. The increases/decreases in vegetation productivity in August and September delayed/advanced the fade stage in entire Inner Mongolia and three ecological zones. In contrast, the increases/decreases in vegetation productivity in June and July advanced/delayed the fade stage in the grassland and desert ecological zone.

Rapid generation of global forest cover map using Landsat based on the forest ecological zones

The easy and ready access to Landsat datasets and the ever-lowering costs of computing make it feasible to monitor the Earth’s land cover at Landsat resolutions of 30 m. However, producing forest-cover products rapidly and on a large scale, such as intercontinental or global, is still a challenging task. By utilizing the huge catalog of satellite imagery as well as the high-performance computing capacity of Google Earth Engine, we proposed an automated pipeline for generating 30-m resolution global-scale forest map from time-series of Landsat images. We describe the methods to create products of forest cover at a global scale. First, we partitioned the landscapes into subregions of similar forest type and spatial continuity. Then, a multisource forest/nonforest sample set was established for machine algorithm learning training. Finally, a random forest classifier algorithm was used to obtain samples automatically, extract the characteristics of satellite images, and establish the forest/nonforest classifier models. Taking Landsat8 images in 2018 as a case, a novel 30-m resolution global forest cover (GFC30) map has been produced. The result shows that by the end of 2018, the total forest area in the world was 3.71 × 109 ha. The accuracy evaluation of GFC30 for 2018 was carried out using verification points via stratified random sampling of a MODIS land cover map (MCD12C1 product in 2012) and verified on high-resolution satellite imagery (e.g., Google Earth). According to the validation result, the overall accuracy of GFC30 for 2018 is 90.94%.

Research on Forest Ecological Benefit Compensation System of Heilongjiang in China

The forest ecological function zone in Heilongjiang Province is an important barrier for maintaining ecological security in my country. Its forest ecological environment has great influence on the sustainable development of regional economy and society and the ecological security of neighboring regions. Based on reading domestic and foreign related documents on forest ecological benefit compensation, this article firstly discusses the current situation and problems of the forest ecological benefit compensation system in Heilongjiang Province. Secondly, it analyzes the current status of the implementation of the international forest ecological benefit compensation system and draws relevant enlightenment to China. At last, it summarizes and propose countermeasures and suggestions to improve the forest ecological benefit compensation system in Heilongjiang Province.

Assessment of Fertility Status of Some Pedons on Basement Complex in the Forest Ecological Zone of Southwestern Nigeria

Assessment of Fertility Status of Some Pedons on Basement Complex in the Forest Ecological Zone of Southwestern Nigeria

De novo profiling of RNA viruses in Anopheles malaria vector mosquitoes from forest ecological zones in Senegal and Cambodia

BackgroundMosquitoes are colonized by a large but mostly uncharacterized natural virome of RNA viruses, and the composition and distribution of the natural RNA virome may influence the biology and immunity of Anopheles malaria vector populations.ResultsAnopheles mosquitoes were sampled in malaria endemic forest village sites in Senegal and Cambodia, including Anopheles funestus, Anopheles gambiae group sp., and Anopheles coustani in Senegal, and Anopheles hyrcanus group sp., Anopheles maculatus group sp., and Anopheles dirus in Cambodia. The most frequent mosquito species sampled at both study sites are human malaria vectors. Small and long RNA sequences were depleted of mosquito host sequences, de novo assembled and clustered to yield non-redundant contigs longer than 500 nucleotides. Analysis of the assemblies by sequence similarity to known virus families yielded 115 novel virus sequences, and evidence supports a functional status for at least 86 of the novel viral contigs. Important monophyletic virus clades in the Bunyavirales and Mononegavirales orders were found in these Anopheles from Africa and Asia. The remaining non-host RNA assemblies that were unclassified by sequence similarity to known viruses were clustered by small RNA profiles, and 39 high-quality independent contigs strongly matched a pattern of classic RNAi processing of viral replication intermediates, suggesting they are entirely undescribed viruses. One thousand five hundred sixty-six additional high-quality unclassified contigs matched a pattern consistent with Piwi-interacting RNAs (piRNAs), suggesting that strand-biased piRNAs are generated from the natural virome in Anopheles. To functionally query piRNA effect, we analyzed piRNA expression in Anopheles coluzzii after infection with O’nyong nyong virus (family Togaviridae), and identified two piRNAs that appear to display specifically altered abundance upon arbovirus infection.ConclusionsAnopheles vectors of human malaria in Africa and Asia are ubiquitously colonized by RNA viruses, some of which are monophyletic but clearly diverged from other arthropod viruses. The interplay between small RNA pathways, immunity, and the virome may represent part of the homeostatic mechanism maintaining virome members in a commensal or nonpathogenic state, and could potentially influence vector competence.

Evaluation of Growth of Toxigenic Strain of Aspergillus flavus on Turmeric-Based Media at Different Water Activities

Climatic conditions of the rain forest ecological zone of Nigeria favour the growth of Aspergillus flavus and subsequent aflatoxin production. This study was carried out to investigate the effect of water activity (0.85, 0.9, 0.95, 0.98 and 0.995 a ) on the lag phase prior to growth and mycelial growth of a toxigenic strain of A. flavus on turmeric-based media at 28±2oC after 12 days incubation period. Four different varieties; UT14, UT25, UT35 and UT46 obtained from National Root Crop Research Institute (NRCRI), Abia State and used in the preparation of the different media. A toxigenic strain of A. flavus isolated from turmeric in Port Harcourt was used in the experiment. The experiment was a 5 x 4 factorial laid out in completely randomized design (CRD), replicated three times. Results showed that regardless of the variety, no growth was observed at 0.85 a at 12 days of incubation. The shortest lag phase prior to growth was obtained at 0.995 a and the longest obtained at 0.90 a Optimal growth was observed at 0.98 a in three varieties (UT14, UT25and UT46), UT35 had marginal optimal growth at 0.995 a . Minimal growth of the A. flavus strain was obtained at 0.90 a at 28±2oC in all varieties. This result could be useful in the storage of turmeric, as this food product could be stored at moisture content of &lt; 85%.