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Land Use and Landscape Pattern Changes on the Inside and Outside of Protected Areas in Urbanizing Selangor State, Peninsular Malaysia

Abstract

Unabated land use changes in developing countries have imperilled the urban ecosystem resilience. An urban protected area is one of the critical systems to absorb disturbance regimes in the metropolitan area, but it is increasingly pressured by urbanization. Therefore, assessing their land use and landscape pattern changes are pivotal to identify the conservation capacity. We developed land use maps for Klang Gate, Bukit Kutu, and Sungai Dusun wildlife reserves to assess their spatial and temporal land use changes between 1988 and 2012. The degree of fragmentation, the intensity of human impact and structural connectedness for these wildlife reserves were also quantified. The findings revealed that Klang Gate which located adjacent to the highly urbanizing area experienced a very significant loss of forest while built-up area and commercial agriculture gradually encroached into the reserve. It also has a higher degree of fragmentation and human impact than the other two reserves. Human impact inside of Klang Gate was concomitant to the outside. However, Bukit Kutu almost undisturbed and Sungai Dusun was slightly intruded by commercial agriculture. The results help different stakeholders, such as managing authorities and policy planners to strategize new land use planning that utilize limited land-based resources for future economic and social development. As the findings showed that urban protected areas alone are not sufficient in maintaining the urban ecosystem; therefore new conservation planning that integrates other urban green spaces at their surrounding is critical to ameliorating the conservation on a long-term basis.

Open access
Mangrove Vegetation Health Assessment Based on Remote Sensing Indices for Tanjung Piai, Malay Peninsular

Abstract

Mangroves critically require conservation activity due to human encroachment and environmental unsustainability. The forests must be conserving through monitoring activities with an application of remote sensing satellites. Recent high-resolution multispectral satellite was used to produce Normalized Difference Vegetation Index (NDVI) and Tasselled Cap transformation (TC) indices mapping for the area. Satellite Pour l’Observation de la Terre (SPOT) SPOT-6 was employed for ground truthing. The area was only a part of mangrove forest area of Tanjung Piai which estimated about 106 ha. Although, the relationship between the spectral indices and dendrometry parameters was weak, we found a very significant between NDVI (mean) and stem density (y=10.529x + 12.773) with R2=0.1579. The sites with NDVI calculated varied from 0.10 to 0.26 (P1 and P2), under the environmental stress due to sand deposition found was regard as unhealthy vegetation areas. Whereas, site P5 with NDVI (mean) 0.67 is due to far distance from risk wave’s zone, therefore having young/growing trees with large lush green cover was regard as healthy vegetation area. High greenness indicated in TC means, the bands respond to a combination of high absorption of chlorophyll in the visible bands and the high reflectance of leaf structures in the near-infrared band, which is characteristic of healthy green vegetation. Overall, our study showed our tested WV-2 image combined with ground data provided valuable information of mangrove health assessment for Tanjung Piai, Johor, Malay Peninsula.

Open access
Mathematical Models and Computer Simulations of Aerial Spraying and Droplets Distribution in a Target Site

Abstract

Mathematical models describing aerial spraying and the distribution of liquid droplets on a target were presented. Relationships based on “free models” with Gaussian distribution of droplet concentrations and “bound models” that account for the impact of disturbances in the velocity field behind agricultural aircraft were expanded, and the hybrid model too. The results of experimental studies were presented and compared with theoretical calculations. The “bound model” was found to be the most effective solution for describing the physical phenomena that accompany the aerial spraying process.

Open access
The Principal Threats to the Standing Water Habitats in the Continental Biogeographical Region of Central Europe

Abstract

This paper discusses threats of standing water habitats of high importance to the European Community in the Continental Biogeographical Region (CBR) of Europe, specifically in Poland, as a reference. The study covers five standing water habitats types distinguished in Natura 2000: 3110, 3130, 3140, 3150, 3160, occurring in 806 Special Areas of Conservation (SACs) in Poland. The most significant threats to standing water habitats in the Continental biogeographical region, result from human-induced changes in hydrological conditions that have modified whole natural systems. Based on multivariate analysis, we found that significant differences in the conservation status of the standing water habitats resulted from a variety of threats, pressures, and activities, among which the most significant are decreased and unstable water resources (3110, 3130, 3140, 3150, 3160), fishing and harvesting aquatic resources (3110, 3130, 3140, 3150, 3160), pollution from use of the catchment (3130, 3140, 3150), improper management and use of the agricultural catchment (3110, 3130, 3140, 3150, 3160) and forest catchment (3110, 3140, 3160), urbanisation, residential and commercial development (3150, 3140), transportation and service corridors (3140> 3160 > 3110, 3150), including parking areas (3140), changes in biocenotic evolution, succession, plant species composition (3110, 3130, 3140, 3150, 3160), succession of invasive species (3130), and more intense touristic exploration (3110, 3130, 3140, 3150, 3160). Only in the case of habitats 3110, 3130, 3140 changes in their conservation status have been associated with climate change.

Open access
The Role of Hillshade, Aspect, and Toposhape in the Woodland Dieback of Arid and Semi-Arid Ecosystems: A Case Study in Zagros Woodlands of Ilam Province, Iran

Abstract

Soil moisture plays a key role in the ecological capability of arid and semi-arid woodland. Reducing soil moisture due to frequent droughts causes pest prevalence and disease outbreak and the consequence of forest dieback. On the other hand, soil moisture is strongly correlated with the amount of radiation received on the Earth’s surface. The sun’s radiation is traditionally described often by aspect and sometimes by toposhape. The use of the hillshade map for estimating solar radiation is possible through developing GIS. The present study aimed to compare the relationship and the ability of these indices to describe the phenomenon of arid and semi-arid woodland decline better and more accurately in a case study in the west of Iran. To this aim, the aspect and toposhape layers were generated in 5 and 12 classes, respectively. Then, the hillshade map in range of 0-255 was made during the peak of summer heat. The comparison of the dieback ratio in the three characteristic histograms showed that the shade index, unlike the other two indicators, had a significant effect on forest drought (R2=0.91 for linear equation and R2=0.94 for quadratic equation). The results indicated that the application of hillshade in describing and analysing ecological processes by relying on soil moisture such as woodland dieback is superior to the other two indicators. It is suggested that this index be used to obtain a risk model to predict woodlands dieback which are under the pressure of frequent droughts due to climate change or other mortal factors.

Open access
A New Method for the Estimation of Hydraulic Permeability, Coefficient of Consolidation, and Soil Fraction Based on the Dilatometer Tests (DMT)

Abstract

The main issue of the paper is the estimation of soil hydraulic permeability based on the DMT test. DMTA, DMTC and SASK methods performed in the Nielisz dam, Stegny and the SGGW Campus of the Warsaw University of Life Sciences sites are described. The article presents the implementation of the dilatometer Marchetti test (DMT) in the determination of soil fraction and effects of its occurrence in the subsoil, tested in the Nielisz dam located in the Wieprz river valley in the Lublin province, and in various sites in Warsaw (Stegny site and SGGW Campus of the Warsaw University of Life Sciences). In order to acquire the needed data, the flat dilatometer test (DMT) method was used. A direct and indirect pressure methodology of interpreting soil swelling was characterized in the article. The paper shows the possibilities of determining sand, silt and clay soil fractions based on po and p 1 pressures from dilatometer tests (DMT) and the effective (σvo) and total (σvo) vertical in situ overburden stress. Additionally, the main advantage of this paper is the proposal of use of a new chart to determine hydraulic permeability and soil fraction, based on DMT tests.

Open access
Shear Strength Enhancement of Cemented Reinforced Sand: Role of Cement Content on the Macro-Mechanical Behavior

Abstract

Sands reinforced by hydraulic binders (cement) have constituted in recent decades a major asset for the expansion of several areas of engineering. The mechanical behavior of sand-cement mixtures has undergone some controversies studied on the Chlef sand. In this paper, we present an experimental study to investigate the mechanical behavior of a sandy soil reinforced by a hydraulic binder (cement), using the direct shear apparatus emphasizing on the shear strength characteristics and the vertical deformation variation of cemented reinforced sand. The parameters used in this study are mainly: relative density (Dr = 80%), normal stress (σn = 100, 200, 400 kPa), water content (3, 7 and 10%), cement content (2.5, 5, 7.5 and 10 %) and cure time (7, 14 and 28 days). The experimental results show that the mechanical characteristics in terms of internal cohesion (C) and internal frication angle (φ) give a better mechanical performance with the binder inclusion, and the cure conditions play an effective role on the improvement of the shear strength. This result also showed that 10% of the cement content gave us a maximum value of shear strength and an optimal influence on the mechanical characteristics. The addition of cement not only improves the shear strength of soil, but also provides diversity in the resistance against the deformations imposed load, which can be established by a dilatant character.

Open access
Nevşehir Castle Region in Turkey Interpreted by the Use of Seismic Surface Wave and Electrical Resistance Measurements Together

Abstract

The underground city beneath the Nevşehir Castle located in the middle of Cappadocia region in Turkey with approximately cone shape is investigated by jointly utilizing the modern geophysical techniques of seismic surface waves and electrical resistivity. The systematic void structure under the Nevşehir Castle of Cappadocia, which is known to have widespread underground cities, is studied by the use of 33 separate two-dimensional profiles ~4-km long where electrical resistivities and seismic surface waves are concurrently measured. Seismic surface wave measurements are inverted to establish the shear-wave velocity distribution while resistivity measurements are inverted to resolve the resistivity distribution. Several high-resistivity anomalies with a depth range 8-20 m point to a systematic void structure beneath the Nevşehir Castle. We were able to effectively isolate the void structure from the embedding structure since the currently employed resistivity instrument has provided us high resolution quality measurements. Associated with the high resistivity anomalies there exist low-velocity depth zones acquired from the surface wave inversions also pointing to a systematic void structure where three-dimensional visualization techniques are used to show the extension of the void structure under the studied area.

Open access
A new Hauterivian palynoflora from the Vale Cortiço site (central Portugal), and its palaeoecological implications for western Iberia

Abstract

Palynofloral assemblages are an invaluable source of information about the interactions between fossil plants and their environments. Here we describe a new Early Cretaceous palynoflora from the Lusitanian Basin in the Estremadura region of central western Portugal. A palynological assemblage of 28 genera and 40 species was extracted from 14 samples collected in the Vale Cortiço clay pit complex near the small village of Ameal (Torres Vedras Municipality). The source is a dark grey mudstone layer belonging to the lower part of the Santa Susana Formation, which is considered to be of early Hauterivian age. The palynoflora is dominated by fern spores and gymnosperm pollen. Bryophyte and lycophyte palynomorphs are also present but subordinate. Angiosperm pollen and algal or dinoflagellate cysts were not recognised in the studied samples. The palynological assemblage represents mixed conifer forest with the ground cover and understorey vegetation dominated by ferns, with patchy occurrences of bryophytes and lycophytes. A riverine environment with surrounding vegetation of open woodland and ground cover primarily of ferns is strongly indicated for the region.

Open access
Structural Inversion Magnitude and its Impacts on the Hydrocarbon Accumulation

Abstract

West Wadi El-Rayan is located in the Western Desert at about 140 km SE of Cairo. Also, it lies between Gindi basin to the east and Abu Gharadig basin to the west. In order to construct a 3D structural model and to delineate the subsurface structure styles of the area, seismic structural interpretation and structural restoration are used. The structural geometry within the area is inverted half-graben, since the area was controlled by reactivation of older faults. The magnitude of the inversion-related shortening in the study area was estimated and was suggested to be strong. The result of the strong inversion magnitude occurred toward northeast of the study area can be concluded that, the area suffered shortening and part of the Jurassic / Early Cretaceous normal faults are reactivated as reverse faults. Also the cap, the main reservoirs and the source rock sections are brought to the surface and thus breached, as well any previous mature source rock becoming non-generative where the dry wells are located. However, any less severe inversion structure in this case where producing wells are located that remain buried and will have a better chance or preserving the structure geometry and therefore top and lateral seal.

Open access