Top PDF Abundance and structure of African baobab (Adansonia digitata) across different soil types in Gonarezhou National Park, Zimbabwe

Abundance and structure of African baobab (Adansonia digitata) across different soil types in Gonarezhou National Park, Zimbabwe

Abundance and structure of African baobab (Adansonia digitata) across different soil types in Gonarezhou National Park, Zimbabwe

This study investigated the abundance and structure of African baobab (Adansonia digitata) across soil group strata in Gonarezhou National Park, Zimbabwe. The study was based on a stratified random sampling design composed of the following soil group substrates: (i) granophyres, (ii) malvernia, and (iii) rhyolite. Belt transects of 0.3 × 0.1 km were randomly laid across soil group. Baobab abundance and population structure were determined from the density and size class distribution, respectively. There were significant differences in plant height and plant density across Gonarezhou soil groups. Study sites on granophyres derived soil group indicated viable abundance and recruitment of baobab population. Whereas the study highlighted a concern over the unbalanced size structure distribution of baobab population on malvernia derived soil group, our results indicated that baobabs are in danger of extirpation on malvernia derived soil group. Baobab community in Gonarezhou tends to occur more densely along environmental gradient of soil group type as influenced by the underlying geological soil substrate of granophyres. Malvernia derived soil group is likely less ideal for baobab recruitment.
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Status of African baobab (Adansonia digitata) across Gonarezhou National Park,

Zimbabwe

Status of African baobab (Adansonia digitata) across Gonarezhou National Park, Zimbabwe

KEY WORDS: Elephants, herbivory, precipitation, savanna, water sources, woodland ABSTRACT: An assessment was done to determine the abundance and structure of baobab (Adansonia digitata) across Gonarezhou National Park, Zimbabwe. Baobabs were sampled on fifteen belt transects of constant width of 300 m with fifteen baobabs in each belt transect determined the length of a particular belt transect between May and June 2012. Our results showed that there were no significant differences in basal area, height and density of baobabs across Gonarezhou. Moreover, elephant (Loxodonta africana ) dung counts and damaged baobabs were similar across Gonarezhou. Our findings suggest a relatively similar spatial effect of elephant herbivory and other disturbance regimes on baobabs in Gonarezhou. We recommend the continuous monitoring of baobab woodland stands across Gonarezhou. © JASEM
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Structure and composition of Androstachys johnsonii woodland across various strata in Gonarezhou National Park, southeast Zimbabwe

Structure and composition of Androstachys johnsonii woodland across various strata in Gonarezhou National Park, southeast Zimbabwe

A One-Way ANOVA using STATISTICA statistical software with strata as categorical predictors and vegetation variables as dependent variables was performed to test the main effects of variables and strata (P-value at 0.05 significance level). For variables with significant differences, differences among means were tested using the Fisher Least Significant Difference (LSD) post-hoc tests to detect differences between the three soil categories. Data were further analyzed through a combination of classification and ordination techniques to explore the associations, patterns and structure of woody vegetation across the three strata. A Principal Component Analysis (PCA) was used to define both the pattern and structure of variables [15] in the different strata using the vegetation variables. Hierarchical Cluster Analysis (HCA) using the weighted pair group average linkage method was performed using a matrix of 30 plots and 41 species, using the species abundance data to classify sampling plots on the basis of their floristic similarity.
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Abundance and Distribution of African Fish Eagles

along Major Rivers in Gonarezhou National Park,

Zimbabwe

Abundance and Distribution of African Fish Eagles along Major Rivers in Gonarezhou National Park, Zimbabwe

Ground surveys for African fish eagles were carried out between March and April 2011. This period coincided with the African fish eagles’ breeding season in Zimbabwe. Direct observation methods of transect counts were used in data collection (Bibby et al., 2000). All African fish eagles seen perched or flying along the selected line transects were counted by two people (one observer and one recorder) while walking downstream (at ~3 km -1 ) in open areas along the river banks from after sunrise to before sunset (7:00–18:00 hrs) with the aid of 10 × 42 binoculars. In this study, we didn’t measure the distance from the observer to the sighted bird(s). A Global Positioning System (GPS) unit was used to record co-ordinates of a particular point corresponding to sighting of the African fish eagles and any encountered nest. Moreover, we did not collect detailed information on the nests themselves, i.e., tree species where the nests were, height of the nest on the tree and also structure of the trees. Data analysis
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Classification and mapping of the woody vegetation of Gonarezhou National Park, Zimbabwe

Classification and mapping of the woody vegetation of Gonarezhou National Park, Zimbabwe

We classified the vegetation of GNP through the analysis of woody species composition. Woody plants represent one of the most distinguishing features of the vegetation in southern Africa (Germishuizen & Meyer 2003; O’Brien, Field & Whittaker 2000), and have been widely used for modelling vegetation structure and physiognomy in the region and elsewhere (Daru et al. 2015; Kubota et al. 2014; O’Brien 1993). A total of 330 relevés were conducted between March and July 2010 (Figure 2), following the methodology of Timberlake, Nobanda and Mapaure (1993). Sampling was targeted to distinct vegetation communities that were clearly recognisable on satellite imagery (Landsat and Google Earth) and/or in the field. A plotless method was used for each relevé, whereby all woody species present within an area of 0.5 ha – 2 ha were recorded and classified in five height classes: seedlings, less than 0.5 m (mainly regeneration), 0.5 m – 3 m (shrubs and young trees), trees taller than 3 m (tall shrubs and trees); and mature trees (canopy height trees). Each species was allocated to a cover-abundance value in each layer using a six-point modified Braun–Blanquet scale: + = < 2%, 1 = 2% – 10%, 2 = 11% – 25%, 3 = 26% – 50%, 4 = 51% – 75% and 5 = 76% – 100%. Any species that could not be reliably identified in the field was collected and later compared with the collection available at the National Herbarium in Harare.
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Caregiver stress across different dementia types

Caregiver stress across different dementia types

On a univariate level without adjusting for any covariates, proportionally more caregivers in the PDD group experienced stress, followed in descending order by the AD+, PD, and ND groups. This is in line with previous findings (Lee et al., 2013; Roland & Chappell, 2017; Shin et al., 2012; Svendsboe et al., 2016). However, when adjusting for caregiver and client risk factors, it became apparent that caregivers in the AD+ group were at higher risk of experiencing stress, which is in line with findings by Mitchell et al. (2015). Of note is however, that Mitchell et al.’s study did not distinguish between PD and PDD, and in our study we expected that caregivers in the PDD group would be at higher risk of carer stress than caregiver in the AD+ group. This result was unexpected and suggests that that having a diagnosis of Alzheimer’s disease and related dementias, predicts caregiver stress above and beyond known correlates of caregiver stress. It may be possible, that the uneven distribution of sample sizes across groups explains this unexpected result, such that the almost three times larger sample size in the AD+ group
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Diversity and abundance of beetle at Kuala Kelapor, National Park, Malaysia

Diversity and abundance of beetle at Kuala Kelapor, National Park, Malaysia

ISSN 1394-5130 208 The biggest logging effect in Asia is reported in the Malay Archipelago where 1.8 million ha of forest land were logged annually (Doll et al. 2014). Furthermore, due to the limited access, biodiversity of Kuala Kelapor National Parkis relatively less disturbed compared to some of the other forests in Malaysia, but the pressure is mounting on this pristine ecosystem. It has been widely discussed about the rise of anthropogenic disturbances in Peninsular Malaysia, where the conservation efforts are lagging (Sodhi et al. 2010; Laurance 2016). Therefore, it is very vital to increase the number of studies on biodiversity assessments in Malaysia in relation to anthropogenic activities and climate change imprints. Malaysia possesses some of the oldest tropical forests which could also serve as a good base study to formulate number of ecological hypotheses on species diversity patterns in tropics.
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Spatial pattern of tree diversity and evenness across forest types in Majella National Park, Italy

Spatial pattern of tree diversity and evenness across forest types in Majella National Park, Italy

Diversity and evenness are two integral components to describe, measure and compare biological diversity of forest communities. This study demonstrated how tree diversity and evenness of an Italian forest site varied with forest types and could be mapped and compared against each other using a combination of satellite image, GIS and ground survey data. The diversity and evenness went parallel to each other i.e. the forest type which was more diverse was also more even. As a broad pattern, majority portion of the study area belonged to medium diversity but high evenness classes. In compari- son to the other similar studies, diversity and evenness of Morrone were of medium level. Findings of the present study might have significant implications in pri- oritizing biodiversity conservation areas of different for- est types/ecoregions, undertaking silvicultural operations and selecting sites or enrichment planting. Further re- search can investigate the variation in mapping accuracy of diversity and evenness using high-resolution image and with less number of field samples in other areas of the park.
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From the results of the stability of soil structure studies and the physical characteristics of the black meadow soil of the mountain meadow in the limited national park (gorkhi-terelj national park)

From the results of the stability of soil structure studies and the physical characteristics of the black meadow soil of the mountain meadow in the limited national park (gorkhi-terelj national park)

The study aims to investigate changes in the physical properties of soil depending on the utilization conditions of the Special Protected National Park compared to the area fenced for more than 10 years. The stability and stabilization of the stabilized mountain meadow soil stabilization and physical properties of soil in the Gorkhi-Terelj National Park (GTNP) resort and limited concentration of tourism. As a result of the study, the stability of the soil structure was 2.8 points in the area of vegetation cover 0-3 cm outside the fence, while the 2.6 layered soil layers above the soils of the vegetation cover. However, the area with vegetation cover within the fence is 4.2 points in soil 0-3 cm and 4 leaves in soil without vegetation cover.
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Variation in Soil Respiration across Soil and Vegetation Types in an Alpine Valley.

Variation in Soil Respiration across Soil and Vegetation Types in an Alpine Valley.

Results Vegetation Vegetation covered 55 to 99% of the soil surface. Four vegetation groups corresponding to suc- cessional dynamics ( S2 Table ) were obtained. The first group was attributed to Petasition para- doxi and represents a pioneer community growing on young soils found along the most dynamic streams in the Nant valley. Plant cover in this group was low (55–74%, S1 Fig ). The characteristic species Petasites paradoxus was abundant in each plot. Anthylis vulneraria and Dryas octopetala were also very common in these calcareous environments. The next group was the Seslerion alliance and can be thought of as the second stage in colonization, with a higher plant cover (72–98%) and species richness. Carex sempervirens and Alchemilla con- juncta were very abundant. Sesleria caerulea, typical Poaceae of this alliance, was also frequent. The third group corresponded to the Poion alpinae alliance and was found in previously for- ested, stable parts of the landscape. Surface cover in this group was almost complete. Abundant species included Dactylis glomerata, Alchemilla vulgaris, Trollius europaeus and Plantago media. The last group was that of Rumicion alpini and was found in areas of high livestock pressure also previously under forest. This group included trampling-tolerant species as well as species avoided by grazers. Common species were the nitrophilous Rumex alpinus and Taraxa- cum officinale, indicative of high soil nutrient status [36 ]. Cow tracks were covered by Poa supina and Plantago major. Overall, floristic richness was maximal in Seslerion and minimal in Rumicion alpini groups (S1 Fig ).
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Structure of Debt Maturity across Firm Types

Structure of Debt Maturity across Firm Types

By contrast, the agency perspective receives little or no support in Cai, Fairchild, and Guney (2008) and Deesomsak, Paudyal, and Pescetto (2009), who focus instead on China and the Asia-Pacific region (Australia, Malaysia, Thailand, and Singapore), respectively. In fact, Cai, Fairchild, and Guney (2008) find that debt maturity is positively related with growth opportunities as predicted by Hart and Moore (1995), suggesting that overinvestment problems are more important in China than underinvestment problems. Another view that finds little support in both studies is the signaling view. The authors attribute the lack of support for the agency and signaling views to the existence of close relationships between firms and their banks, which renders information and agency considerations much less relevant. The tax and liquidity risk hypotheses, on the other hand, receive somewhat greater support in these studies. Kirch, Renato, and Terra (2012) focus on five South American economies (Argentina, Brazil, Chile, Peru, and Venezuela) and report results that lend partial support for each of the four major groups of debt maturity hypotheses. Most closely related to ours is perhaps the study by Arslan and Karan (2006) who, like us, focus on Turkey. Differently from us, however, these authors focus on publicly-traded industrial firms and explore the corporate governance implications of debt maturity structure. Their findings are generally consistent with the agency and signaling hypotheses but not with the tax hypotheses, whereas the relevance of the liquidity risk hypothesis is not investigated.
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Estimating the Abundance and Composition of Soil Seed Bank at Bekol Savanna in Baluran National Park, West Java

Estimating the Abundance and Composition of Soil Seed Bank at Bekol Savanna in Baluran National Park, West Java

136 spesies asing berpengaruh terhadap komposisi, kerapatan dan keanekaragaman spesies simpanan biji. Sejumlah spesies tumbuhan yang ditemukan pada suatu komunitas tumbuhan dapat disebabkan oleh perubahan kondisi tanah. Perubahan kondisi tanah juga dapat mempengaruhi persistensi biji dalam tanah. Tjitrosoedirdjo et al. ( 2013 ) menyatakan bahwa invasi A. nilotica meningkatkan bahan organik tanah dan kapasitas tukar kation sehingga mendukung pertumbuhan tumbuhan berdaun lebar. Adanya invasi A. nilotica tersebut dapat mempengaruhi input biji ke dalam tanah yang berakibat pada peningkatan keanekaragaman spesies simpanan biji. Perubahan tersebut dapat terjadi akibat dari kegiatan manusia, kerusakan tanah dan penggunaan bahan kimia untuk menekan populasi gulma berdaun lebar. Keanekaragaman spesies gulma berdaun lebar sangat bergantung pada komposisi simpanan biji dalam tanah dan juga berkorelasi dengan tingkat gangguan yang dialami (Hosseini et al., 2014 ). Perubahan kondisi lingkungan dan biotik memicu munculnya spesies asing yang dapat menghambat pertumbuhan spesies asli. Proses pemulihan kondisi lingkungan bergantung pada perkecambahan biji, reproduksi vegetatif (batang atau akar), biji yang disebarkan oleh agen biotik (seranggga, hewan dan burung) dan abiotik (angin dan air), serta simpanan biji dalam tanah (soil seed
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Annotation of Information Structure: an Evaluation across different Types of Texts

Annotation of Information Structure: an Evaluation across different Types of Texts

Major objectives in the design of the LISA guidelines were (i) reliability of annotation, (ii) language independence, and (iii) openness towards different theories. Whereas the first objective is a standard one for many guidelines, the second follows from the diversity of language data to be annotated within the SFB. The third objective results from the wish to be rather independent from specific theories, which is of course a difficult enterprise. Another important criterion for the guidelines is applicability to different modalities and text types.

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Soil structure interaction of RC building with different foundations and soil types

Soil structure interaction of RC building with different foundations and soil types

The based on previous case study deals with the effect of soil structure interaction on RC building. The objective of this present work is to study with and without soil structure interaction effect of layered soil on structural behavior of building supported on pile and raft foundation when subjected to seismic load. During dynamic loading the consideration of fixed support reduces the overall strength of the structure and brings out changes in frequency as well as natural time period of the structure. So following objectives are determine to increasing the time period of the building.
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Soil Structure Interaction of Framed Structure Supported on Different Types of Foundation

Soil Structure Interaction of Framed Structure Supported on Different Types of Foundation

Ravikumar C M et.al (2012), Addressed many buildings have irregular configurations in both plan and elevation. This in a future earthquake subjected to devastating such type of buildings. In case, it identifies the necessary performance of the new and existing structure to withstand against disaster. This paper studid the two kinds of irregularities in the structure, namely plan irregularity with diaphragm and geometric discontinuity and vertical irregularity with sloping ground and setback. This irregularity is framed as per IS 1893 (part 1), class 7.1 code. The considered in identifying the most vulnerable buildings, in both linear and nonlinear seismic demands to identify the performed various analytical approaches. It is also tested by different lateral loads for various irregular buildings with the performance of pushover analysis. Finally, the result shows that the building capacity may be significant, but the seismic demand differs with respect to the configuration. The eccentricity between centre of rigidity and centre of mass is differ in the absence of dual system. This study generates the awareness of seismic vulnerability in practicing engineering.
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Study of Soil Structure Interaction of R.C.Frame Structure Supported on Different Types of Foundation

Study of Soil Structure Interaction of R.C.Frame Structure Supported on Different Types of Foundation

In the analysis of R.C. frame structure, the base is considered to be fixed neglecting the effect of soil and foundation flexibility. Flexibility of the soil causes the decrease in stiffness resulting increase in the natural period of the structure. Such as increase in the natural periods, changes the seismic response of structure, it may be an important issue for design considerations. The present study provides systematic guidelines for determining the natural periods of frame buildings due to the effect of soil-flexibility and identification of spring stiffness for different regular and irregular story buildings and various influential parameters have identified and the effect of the same on change in natural periods has to be studied. The study has carried out for building with isolated and pile foundations for different soil conditions like soft, medium, and a comparison between the regular and irregular buildings and natures of change in the natural periods has to be present.
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A Review on Different Types Soil Stabilization Techniques

A Review on Different Types Soil Stabilization Techniques

evaporation which in turn results into increased plastic limit of soil i.e. drying out and absorption [5, 8]. The effect can be explained from Figure 1 for 6 soils at a moisture content of 35% and plastic limit 25%. Addition of 2% lime will change the plastic limit to 40% so that the moisture content of the soil will be 5% below plastic limit instead of 10% above plastic limit [5]. Sherwood investigated the decrease in plasticity as brought about in first instance by cation exchange in which cations of sodium and hydrogen are replaced by calcium ions for which the clay mineral has a greater water affinity. Even in soils (e.g. calcareous soils) where, clay may be saturated with calcium ions, addition of lime will increase pH and hence increase the exchange capacity. Like cement, lime when reacts with wet clay minerals result into increased pH which favors solubility of siliceous and aluminous compounds. These compounds react with calcium to form calcium silica and calcium alumina hydrates, a cementitious product similar to those of cement paste. Natural pozzolanas materials containing silica and alumina (e.g. clay minerals, pulverized fly ash, PFA, blast furnace slag) have great potential to react with lime. Lime stabilizations technology is mostly widely used in geotechnical and environmental applications. Some of applications include encapsulation of contaminants, rendering of backfill (e.g. wet cohesive soil), highway capping, slope stabilization and foundation improvement such as in use of lime pile or lime-stabilized soil columns. However, presence of sulphur and organic materials may inhibit the lime stabilization process. Sulphate (e.g. gypsum) will react with lime and swell, which may have effect on soil strength.
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The Effect of Different Soil Management Practices on the Structure of Vineyard Soil

The Effect of Different Soil Management Practices on the Structure of Vineyard Soil

especially the structure of soil (Pagliai et al. 1987; Mbagwu 1992; Obi and Ebo, 1995). In G+NPK3 (6.99±0.33), the most favourable values of the critical level of soil organic matter (statistically significant in comparison to all treatments) were observed during the period (2008-2011). Similarly, the values of crust index were the most favourable in G+NPK3. Index of crusting (I c ) is a very important parameter of soil structure based on textural composition and soil organic matter content (Lal and Shukla 2004). Soil crust formation is dependent on soil tillage and fertilization as presented by Šimanský et al. (2008). In our case, the effect of soil texture was eliminated because the experiment was based on one soil type with a defined particle size distribution (569 g kg -1 of sand, 330 g kg -1 of silt and
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Structure, Aboveground Biomass, and Soil Characterization of Avicennia marina in Eastern Mangrove Lagoon National Park, Abu Dhabi

Structure, Aboveground Biomass, and Soil Characterization of Avicennia marina in Eastern Mangrove Lagoon National Park, Abu Dhabi

Such studies about mangrove population structure are necessary since mangrove conservation and management efforts highly depend on a deep understanding of the dynamics of mangrove vegetation structure. A clear understanding of the origin and the ecological dynamics of mangrove vegetation in a given area is vital before embarking on protection and conservation efforts such as afforestation and re-afforestation. Therefore, the main objective of this work is to assess mangrove population and vegetation structure specific to Eastern Mangrove Lagoon National Park, Abu Dhabi (a mangrove treasure to UAE). The only mangrove species that grows widely in the park is the Avicennia marina, because it is the only species capable of surviving the harsh arid climate conditions and high saline seawater environment of Abu Dhabi (Boer & Aspinall, 2009). Data about mangrove structural properties in such environment has been lacking; therefore, the study will provide valuable information about the forest canopy status, mortality rate, height, density, crown spread, stem number, and DBH. Moreover, it will utilize in situ data to estimate aboveground biomass and basal area of mangrove forest. A better
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Mapping of Degraded Soil Properties in Gunung Leuser National Park

Mapping of Degraded Soil Properties in Gunung Leuser National Park

Abstract. Deforestation causes a decrease in soil fertility. The knowledge of soil fertility in a landscape provides us information about land management. The nature of soil on each area was diversed therefore it is necessary to map the soil properties. The objective of the research was to map the properties distribution of forests land in degraded areas, namely land of a former privately owned oil palm plantation in Gunung Leuser National Park (GLNP) forest area. The study used a continuous grid interpolation method which was further formed polygons of soil properties. The soil types were inceptisol and ultisol. According to the study, most of the soils were fine-textured types, allowing surface runoff easily occurred on less vegetated areas and causing soil erosion. Soil water content on widest area was ranging from 26.98 - 29.50% with an area of 14.38 hectares (42.91% of the research area). Organic materials were limited and soil pH was low. The study concluded that soils in the research area were less fertile. However, restoration efforts would be very possible to conduct because a amount of tree species were adaptive to soil which had low fertility.
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