scholarly journals PHYTODIVERSITY AND SOIL STUDY OF SHIWALIK HILLS OF ILAM, NEPAL: AN ECOLOGICAL PERSPECTIVE

2013 ◽  
Vol 18 ◽  
pp. 77-83 ◽  
Author(s):  
Ramkrishna Nirola ◽  
Pramod Kumar Jha

The Siwalik range (locally known as Churia hills) in Nepal comprise a total area of 1,886,000 ha, equivalent to 13% of the country’s total area and consists of hills, steep land slopes, gorges, large spans of river and temporary streams. Study of different kinds of plants, soil and climate and the quantitative analysis of vegetation structure and composition as well as soil analysis at three Village Development Committees (VDCs) of Siwalik hills of Ilam was undertaken. A total number of 137 flowering plants and 8 pteridophytes are reported in the present study. Shorea robusta, Terminalia alata and Semecarpus anacardium are the most dominant species of the entire study area. The Siwalik range with late tertiary exposed rocks consists of fine grained sandstone with pockets of clay, shale, conglomerate and freshwater limestone. The vegetation is much more diverse and intact ecologically than expected from a distant observation. DOI: http://dx.doi.org/10.3126/eco.v18i0.9414Ecoprint: An International Journal of EcologyVol. 18, 2011 Page: Uploaded date: 12/22/2013 

2018 ◽  
Vol 44 (3) ◽  
pp. 399-405 ◽  
Author(s):  
Arif Zereen ◽  
Andleeb Anwar Sardar

Multivariate analysis using two-way indicator species analysis (TWINSPAN) and Canonical correspondence analysis (CCA) were used to classify the phytosociology of the District Vehari, Pakistan. A total of 35 plant species belonging to 23 families were recorded. The first level TWINSPAN divided the vegetation of entire study area into two major communities which were subsequently separated into subcommunities. Each major and sub-community was named following the most important dominant species. CCA identified the relationship of vegetation structure to specific environmental factors. This relationship was studied by CANOCO analysis. In the CCA of all the species for Vehari, soil pH and water pH and EC were the most important variables influencing the species distribution. This survey offers key information regarding vegetation and would be helpful for the conservation of biodiversity of the area under study.


2003 ◽  
Vol 154 (8) ◽  
pp. 305-313 ◽  
Author(s):  
Roman Eyholzer ◽  
Martin Baumann ◽  
Rolf Manser

Faced with the challenging task of balancing forest interests and wildlife, the Swiss Forest Agency initiated the pilot programme«Game and Forest», which is committed to a philosophy of goal-oriented management practice and a redesign of forestry subsidizing. Within this programme the diverse goals of forestry and hunting have been amalgamated to a superimposed goal and set out in a corresponding contract. The Game-Forest-Management-Tool (GFMT) has been divised to simulate the effect of various strategies to deal with the complex problems of forest-wildlife. Optimal contract-fulfilling procedures can be simulated on a PC using this technical tool. The efficiency of the measures suggested by simulations that were carried out are being tested in a study area within the pilot programme, «Game and Forest». Half way through this trial, after two years, we can say that there has been no significant increase of non-browsed areas. In 2004, after the collection of data for the entire study area, we will be able to tell whether applying this computer simulated strategy truly leads to an augmentation of non-browsed area and a decrease in bark-peeled forests in the pilot area.


2021 ◽  
Vol 13 (11) ◽  
pp. 2129
Author(s):  
Fei Zhao ◽  
Lu Song ◽  
Zhiyan Peng ◽  
Jianqin Yang ◽  
Guize Luan ◽  
...  

Using toponym data, population data, and night-time light data, we visualized the development index of the Yi, Wa, Zhuang, Naxi, Hani, and Dai ethnic groups on ArcGIS as well as the distribution of 25 ethnic minorities in the study area. First, we extracted the toponym data of 25 ethnic minorities in the study area, combined with night-time light data and the population proportion data of each ethnic group, then we obtained the development index of each ethnic group in the study area. We compared the development indexes of the Yi, Wa, Zhuang, Naxi, Hani, and Dai ethnic groups with higher development indexes. The results show that the Yi nationality’s development index was the highest, reaching 28.86 (with two decimal places), and the Dai nationality’s development index was the lowest (15.22). The areas with the highest minority development index were concentrated in the core area of the minority development, and the size varied with the minority’s distance. According to the distribution of ethnic minorities, we found that the Yi ethnic group was distributed in almost the entire study area, while other ethnic minorities had obvious geographical distribution characteristics, and there were multiple ethnic minorities living together. This research is of great significance to the cultural protection of ethnic minorities, the development of ethnic minorities, and the remote sensing mapping of lights at night.


2021 ◽  
Vol 13 (1) ◽  
pp. 454-468
Author(s):  
Yumeng Song ◽  
Jing Zhang

Abstract We integrated hyperspectral and field-measured chlorophyll-a (Chl-a) data from the Kristalbad constructed wetland in the Netherlands. We developed a best-fit band ratio empirical algorithm to generate a distribution map of Chl-a concentration (C chla) from SPOT 6 imagery. The C chla retrieved from remote sensing was compared with a water quality model established for a wetland pond system. The retrieved satellite results were combined with a water quality model to simulate and predict the changes in phytoplankton levels. The regression model provides good retrievals for Chl-a. The imagery-derived C chla performed well in calibrating the simulation results. For each pond, the modeled C chla showed a range of values similar to the Chl-a data derived from SPOT 6 imagery (10–25 mg m−3). The imagery-derived and prediction model results could be used as the guiding analytical tools to provide information covering an entire study area and to inform policies.


1985 ◽  
Vol 117 (9) ◽  
pp. 1117-1126 ◽  
Author(s):  
Ronald M. Weseloh

AbstractThe impact of predation by Calosoma sycophanta L. on an increasing prey population was assessed by recapturing marked adult beetles, periodically observing tagged gypsy moth pupae, and examining gypsy moth pupal remains in different microhabitats. Adult beetles dispersed in random directions but many tended to remain near the trap at which they were originally caught, suggesting a low dispersal potential. About 75% of the adult beetles present in the plot on one day were still present the next day. Capture–recapture estimates suggested that there were at most about 250 male beetles and half as many females/ha in the plot. Calosoma larvae destroyed 70% of tagged gypsy moth pupae under burlap bands on tree trunks near ground level, which was much more than any other mortality factor. Although this percentage was the same when mortality was assessed by looking at pupal remains within 5 m of the ground on tree trunks, pupae higher in trees and on leaves were not attacked as frequently. On average, about 40% of the pupae present in the entire study area were destroyed by Calosoma larvae. Each female beetle in the site would have had to produce about 30 progeny to have this effect. These data suggest that a relatively low number of adult beetles can have a substantial impact on gypsy moth populations.


2021 ◽  
Vol 6 (24) ◽  
pp. 213-225
Author(s):  
Shazad Jamal Jalal ◽  
Tajul Ariffin Musa ◽  
Ami Hassan Md Din ◽  
Wan Anom Wan Aris

Gravity data and computing gravity anomalies are regarded as vital for both geophysics and physical geodesy fields. The mountainous areas of Iraq are characterized by the lack of regional gravity data because gravity surveys are rarely performed in the past four decades due to the Iraq-Iran war and the internal unstable political situation of this particular region. In addition, the formal map of the available terrestrial gravity which was published by the French Database of Bureau Gravimetrique International (International Gravimetric Bureau-in English) (BGI), introduces Iraq and the study area as a remote area and in white color because of the unavailability of gravity data. However, a dense and local (not regional) gravity data is available which was conducted by geophysics researchers 13 years ago. Therefore, the regional gravity survey of 160 gravity points was performed by the authors at an average 11 km apart, which was covers the whole area of Sulaymaniyah Governorate (part of the mountainous areas of Iraq). In spite of Although the risk of mine fields within the study area, suitable safe routes as well as a helicopter was used for the gravity survey of several points on the top of mountains. The survey was conducted via Lacoste and Romberg geodetic gravimeter and GPS handheld. The objective of the study is to determine and map the gravity anomalies for the entire study area, the data of which would assist different geosciences applications.


Author(s):  
S. Anitha ◽  
K. T. Gurumurthy Ganapathi

An investigation was undertaken in Tommaladahalli (566.13 ha) micro-watershed of Tarikere taluk, Chikkamagaluru district of Karnataka to assess available nutrient status in the surface soils. About 118 surface soil samples were collected grid wise by using cadastral map at 250 m grid interval and were analyzed for their fertility status using standard procedures. Soil fertility maps were prepared by means of interpolation method called Krigging. The results revealed that the pH, electrical conductivity, and organic carbon were ranged from 5.37 to 9.06, 0.065 to 0.466 dS m-1 and 0.33 to 1.62 per cent respectively. The available N, P2O5, K2O were ranged from 175.6 to 545.6 kg ha-1, 11.8 to 61.1 kg ha-1 and 122.7 to 491.4 kg ha-1, respectively. The available nitrogen and phosphorus were low to medium, where as potassium content was medium to high in the entire study area. Micronutrients viz. zinc, iron and boron were sufficient and were ranged from 0.34 to 1.17 mg kg-1, 2.03 to 21.86 mg kg-1 and 0.30 to 0.89 mg kg-1 respectively.


2019 ◽  
Vol 11 (23) ◽  
pp. 2736 ◽  
Author(s):  
Jueying Bai ◽  
Qian Cui ◽  
Wen Zhang ◽  
Lingkui Meng

A method is proposed for the production of downscaled soil moisture active passive (SMAP) soil moisture (SM) data by combining optical/infrared data with synthetic aperture radar (SAR) data based on the random forest (RF) model. The method leverages the sensitivity of active microwaves to surface SM and the triangle/trapezium feature space among vegetation indexes (VIs), land surface temperature (LST), and SM. First, five RF architectures (RF1–RF5) were trained and tested at 9 km. Second, a comparison was performed for RF1–RF5, and were evaluated against in situ SM measurements. Third, two SMAP-Sentinel active–passive SM products were compared at 3 km and 1 km using in situ SM measurements. Fourth, the RF5 model simulations were compared with the SMAP L2_SM_SP product based on the optional algorithm at 3 km and 1 km resolutions. The results showed that the downscaled SM based on the synergistic use of optical/infrared data and the backscatter at vertical–vertical (VV) polarization was feasible in semi-arid areas with relatively low vegetation cover. The RF5 model with backscatter and more parameters from optical/infrared data performed best among the five RF models and was satisfactory at both 3 km and 1 km. Compared with L2_SM_SP, RF5 was more superior at 1 km. The input variables in decreasing order of importance were backscatter, LST, VIs, and topographic factors over the entire study area. The low vegetation cover conditions probably amplified the importance of the backscatter and LST. A sufficient number of VIs can enhance the adaptability of RF models to different vegetation conditions.


Geophysics ◽  
1998 ◽  
Vol 63 (5) ◽  
pp. 1507-1519 ◽  
Author(s):  
B. A. Hardage ◽  
J. L. Simmons ◽  
V. M. Pendleton ◽  
B. A. Stubbs ◽  
B. J. Uszynski

A study was done at Nash Draw field, Eddy County, New Mexico, to demonstrate how engineering, drilling, geologic, geophysical, and petrophysical technologies should be integrated to improve oil recovery from Brushy Canyon reservoirs at depths of approximately 6600 ft (2000 m) on the northwest slope of the Delaware basin. These thin‐bed reservoirs were deposited in a slope‐basin environment by a mechanism debated by researchers, a common model being turbidite deposition. In this paper, we describe how state‐of‐the‐art 3-D seismic data were acquired, interpreted, integrated with other reservoir data, and then used to improve the sitting of in‐field wells and to provide facies parameters for reservoir simulation across this complex depositional system. The 3-D seismic field program was an onshore subsalt imaging effort because the Ochoan Rustler/Salado, a high‐velocity salt/anhydrite section, extended from the surface to a depth of approximately 3000 ft (900 m) across the entire study area. The primary imaging targets were heterogenous siltstone and fine‐grained sandstone successions approximately 100 ft (30 m) thick and comprised of complex assemblages of thin lobe‐like deposits having individual thickness of 3 to 6 ft (1 to 2 m). The seismic acquisition was complicated further by (1) the presence of active potash mines around and beneath the 3-D grid that were being worked at depths of 500 to 600 ft (150 to 180 m), (2) shallow salt lakes, and (3) numerous archeological sites. We show that by careful presurvey wave testing and attention to detail during data processing, thin‐bed reservoirs in this portion of the Delaware basin can be imaged with a signal bandwidth of 10 to 100 Hz and that siltstone/sandstone successions 100 ft (30 m) thick in the basal Brushy Canyon interval can be individually detected and interpreted. Further, we show that amplitude attributes extracted from these 3-D data are valuable indicators of the amount of net pay and porosity‐feet in the major reservoir successions and of the variations in the fluid transmissivity observed in production wells across the field. Relationships between seismic reflection amplitude and reservoir properties determined at the initial calibration wells have been used to site and drill two production wells. The first well found excellent reservoir conditions; the second well was slightly mispositioned relative to the targeted reflection‐amplitude trend and penetrated reservoir facies typical of that at other producing wells. Relationships between seismic reflection amplitude and critical petrophysical properties of the thin‐bed reservoirs have also allowed a seismic‐driven simulation of reservoir performance to be initiated.


2012 ◽  
Vol 178-181 ◽  
pp. 751-755
Author(s):  
Yong Zhang ◽  
Zheng Qi Gu ◽  
Zhen Wang ◽  
Yong Yu

For study the law of urban buildings, in particular, the buildings at both roads’ sides in crossroads impacting on the diffusion of automobile exhaust, using CFD, combined with meteorological wind,simulates a crossroads automobile exhaust diffusion processing during waiting 35s. The results are following: in poor circulation areas, CO volume fraction in the buildings near-Earth space is up to 1.0e-7 and more than 100 times average value of the entire study area, so buildings structural layout has great influence. After Analysis, propose that local meteorological wind direction and speed should be considered and different height gradient design should be selected in buildings structural layout, so that the exhaust spread rapidly and drift to the urban high altitude, in order to improve air quality.


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