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. 相似文献
In this work, the X-ray Photoelectron Spectroscopy (XPS) technique is utilized to analyze the surface chemical composition of particulate matter (PM) which was collected from various locations at Jeddah, Saudi Arabia. The main elements found on the surface of PM are carbon (C), oxygen (O) and silicon (Si) with combined percentage of 89.4–94.9 while traces of nitrogen (N), calcium (Ca), aluminum (Al), sodium (Na), chlorine (Cl), manganese (Mg), and sulfur (S) were also present. The analyzed XPS chemical state of C, O and Si was further used to determine their bonding with other elements occurring over the surface of PM. Carbon was found in the form of carbides (18.86%), fluorides (2.39%) and carbonates (78.75%); oxygen was observed as oxides (21.05%) and hydroxides (73.42%) of other metals; and silicon was detected as silicones (12.16%), nitrides (82.53%) and silicates (5.25%). The particle size of a PM is also of great concern for health issues, and thus has been investigated by the Field Emission Scanning Electron Microscope (FESEM). The Energy Dispersive X-ray Spectroscopy (EDS) was employed for cross verification of detected elements by XPS. 相似文献
A long-term (1948 to 2012) trend of precipitation (annual, pre-monsoon, monsoon, and post-monsoon seasons) in Bangladesh was analyzed in different regions using both parametric and nonparametric approaches. Moreover, the possible teleconnections of precipitation (annual and monsoon) variability with El Niño/Southern Oscillation (ENSO) episode and Indian Ocean Dipole (IOD) were investigated using both average and individual (both positive and negative) values of ENSO index and IOD. Our findings suggested that for annual precipitation, a significant increasing monotonic trend was found in whole Bangladesh (4.87 mm/year), its western region (5.82 mm/year) including Rangpur (9.41 mm/year) and Khulna (4.95 mm/year), and Sylhet (10.12 mm/year) and Barisal (6.94 mm/year) from eastern region. In pre-monsoon, only Rangpur (2.88 mm/year) showed significant increasing trend, while in monsoon, whole Bangladesh (3.04 mm/year), Sylhet (7.17 mm/year), and Barisal (6.94 mm/year) showed similar trend. In post-monsoon, there was no significant trend. Our results also revealed that the precipitation (annual or monsoon) of whole Bangladesh and almost all of the spatial regions did not show any significant correlation with ENSO events, whereas the average IOD values showed significant correlation only in monsoon precipitation of western region. The individual positive IODs showed significant correlation in whole Bangladesh, western region, and its two divisions (Rajshahi and Khulna). So, in the context of Bangladesh climate, IOD has the more teleconnection to precipitation than that of ENSO. Our findings indicate that the co-occurrence of ENSO and IOD events may suppress their influence on each other.
We investigate the composition of 63 C2-C10 nonmethane hydrocarbons (NMHCs), methane (CH4) and carbon monoxide (CO), in Jeddah, Mecca, and Madina (Saudi Arabia), in Lahore, (Pakistan), and in Singapore. We established a database with which to compare and contrast NMHCs in regions where ambient levels and emissions are poorly characterized, but where conditions are favorable to the formation of tropospheric ozone, and where measurements are essential for improving emission inventories and modeling. This dataset will also serve as a base for further analysis of air pollution in Western Saudi Arabia including, but not limited to, the estimation of urban emissions and long range pollution transport from these regions. The measured species showed enhanced levels in all Saudi Arabian cities compared to the local background but were generally much lower than in Lahore. In Madina, vehicle exhaust was the dominant NMHC source, as indicated by enhanced levels of combustion products and by the good correlation between NMHCs and CO, while in Jeddah and Mecca a combination of sources needs to be considered. Very high NMHC levels were measured in Lahore, and elevated levels of CH4 in Lahore were attributed to natural gas. When we compared our results with 2010 emissions from the MACCity global inventory, we found discrepancies in the relative contribution of NMHCs between the measurements and the inventory. In all cities, alkenes (especially ethene and propene) dominated the hydroxyl radical (OH) reactivity (kOH) because of their great abundance and their relatively fast reaction rates with OH. 相似文献
Infrared thermography has increasingly gained importance because of environmental and technological advancements of this method and is applied in a variety of disciplines related to non-isothermal flow. However, it has not been used so far for quantitative thermal analysis in saturated porous media. This article suggests infrared thermographic approach to obtain the entire surface temperature distribution(s) in water-saturated porous media. For this purpose, infrared thermal analysis is applied with in situ calibration for a better understanding of the heat transfer processes in porous media. Calibration is achieved with a combination of invasive sensors which are inserted into the medium and non-invasive thermal sensors in which sensors are not inserted to measure temperatures but it works through the detection of infrared radiation emitted from the surface. Thermocouples of relatively thin diameter are used to minimize the disturbance for flow. Thermocouples give the temperature values at specified positions inside the porous medium, and these values are compared with the values suggested by the infrared thermographic device at the same positions, in the calibration exercise. The calibration process was repeated for different temperatures and flow rates to get the temperature distributions of the whole material inside the system. This technique enables us to measure accurate two-dimensional temperature distributions, which is not possible by using thermocouples only. Continuous point heat sources at different flow rates and temperatures are studied experimentally. Additionally, it offers numerical simulations of the experiments utilizing a finite element-based model. A two-dimensional density and viscosity-dependent flow and transport model accounting for thermal dispersion is utilized to simulate the experimental results. Possible small heat losses from the surface are incorporated in the model according to the properties and thickness of the Plexiglass material used for the construction of the experiment tank. The numerical results agree well with the experimental observations. 相似文献