scholarly journals Assessing grazing intensity plant frequency in Kordofan Region

2015 ◽  
Vol 4 (2) ◽  
pp. 27-37
Author(s):  
Yousif Mohamed Zainelabdeen Hamed ◽  
Abdelrahman A Khatir ◽  
MAM Mohamed ◽  
Khalid H Mohamed ◽  
Ahmed IA Eltome
Keyword(s):  
Growth Performance ◽  
Performance Indicators ◽  
Rainy Season ◽  
Negative Impact ◽  
Grazing Intensity ◽  
The North ◽  
Level Ii ◽  
Plant Frequency ◽  
Preferred Species ◽  
Different Levels

This study was conducted in Um "Nabag" (15km north of "Bara"), "Dilling" (160km south of "Elobeid") and "Eldemiokya" (30km east of "Elobeid"). The main objective of this study is to assess the effect of grazing on growth performance of natural rangelands in Kordofan region. The specific objectives: To assess the effect of grazing level on vegetation frequency. The results showed different levels of grazing intensity at different sites as indicated by plants frequency and biomass. Intensive grazing levels were found at Bara in the north, early and late in the rainy season but in Dilling it was not found in the late in the rainy season for both seasons (2008 and 2009) which indicated longer stay of herders in "Bara" area as a rainy season residences. Frequency of the species between non- grazed and grazed areas showed a decrease for the two seasons especially for preferred species at the different sites as in the case of Eragrostis termula and Cenchrus biflorus in (2008 ),Similar results were observed in (2009) with Fimbirsty dichotomo and Cenchrus biflorus. The study recommended that grazing level can be used as practical mean to assess utilization level as expressed by growth performance indicators including frequency. Level (II) is expected to result in negative impact on rangeland plants growth performance. DOI: http://dx.doi.org/10.3126/ije.v4i2.12622 International Journal of Environment Vol.4(2) 2015: 27-37

Biological effects of low-intensity radiofrequency fields and risk assessment for biota

2020 ◽  
Vol 60 (9) ◽  
pp. 592-596
Author(s):  
Elena I. Sarapultseva ◽  
Darya V. Uskalova ◽  
Ksenya V. Ustenko
Keyword(s):  
Radio Frequency ◽  
Electromagnetic Radiation ◽  
Electromagnetic Fields ◽  
Negative Impact ◽  
Biological Effects ◽  
High Sensitivity ◽  
Communication Technologies ◽  
Natural Ecosystems ◽  
Low Intensity ◽  
Different Levels

Despite the fact that there are still conflicting opinions about the damage caused by modern wireless communication technologies, most scientists report on the negative biological effects of low-intensity radio frequency electromagnetic radiation at different levels of the organization of live nature. There is no doubt that there is a need not only for a sanitary and hygienic assessment of man-made electromagnetic effects on humans, but also for an environmental assessment for biota. The purpose of the study was to assess the potential environmental risk of electromagnetic impact in the centimeter range on natural ecosystems. The initial data were the authors' own results in the field of radiobiology of non-ionizing radiation, as well as published of other researchers. The article analyzes the biological effects of radio frequency electromagnetic fields detected in organisms of different systematic groups and levels of organization. The data on the non-thermal biological effects of electromagnetic fields indicate a high sensitivity of different species to this factor. The analyzed research results emphasize the need to take into account the features of non-thermal effects of electromagnetic radiation on biota, since these radiations can have a negative impact on different hierarchical levels in natural ecosystems.

scholarly journals Innovative entrepreneurship in emerging and developing economies: the effects of entrepreneurial competancies and institutional voids

2021 ◽  
Author(s):  
Amirmahmood Amini Sedeh ◽  
Amir Pezeshkan ◽  
Rosa Caiazza
Keyword(s):  
Developing Countries ◽  
Developing Economies ◽  
Negative Impact ◽  
Institutional Voids ◽  
Developed Economies ◽  
Key Drivers ◽  
Innovation Barriers ◽  
Entrepreneurial Competencies ◽  
Emerging And Developing Countries ◽  
Different Levels

AbstractInnovative entrepreneurship is one of the key drivers of economic development particularly for less developed economies where the economic growth is at the forefront of policymakers’ agenda. Yet, the research on how various factors at different levels interact and bring about innovative entrepreneurship in emerging and developing countries remains relatively scarce. We address this issue by developing a multilevel framework that explains how entrepreneurial competencies attenuate the negative impact of innovation barriers. Our analysis on a sample of individuals from 24 economies, 17 developing and 7 emerging countries, reveals that entrepreneurial competencies become more instrumental for innovative entrepreneurship when general, supply-side, and demand-side innovation barriers are higher. The findings offer unique insights to policymakers particularly in developing countries interested in promoting innovative entrepreneurship and to entrepreneurs and investors seeking to establish and support innovative ventures.

Agriculture expansion and deforestation in seasonally dry forests of north-west Argentina

2005 ◽  
Vol 32 (2) ◽  
pp. 140-148 ◽  
Author(s):  
H. RICARDO GRAU ◽  
N. IGNACIO GASPARRI ◽  
T. MITCHELL AIDE
Keyword(s):  
Global Trends ◽  
North West ◽  
Conservation Policies ◽  
Seasonally Dry ◽  
The North ◽  
Agriculture Expansion ◽  
Soybean Price ◽  
Different Levels ◽  
Semi Arid ◽  
Arid Chaco

In Argentina, deforestation due to agriculture expansion is threatening the Semi-arid Chaco, one of the largest forested biomes of South America. This study focuses on the north-west boundary of the Argentine Semi-arid Chaco, where soybean is the most important crop. Deforestation was estimated for areas with different levels of soil and rainfall limitation for agriculture between 1972 and 2001, with a finer analysis in three periods starting in 1984, which are characterized by differences in rainfall, soybean price, production cost, technology-driven yield and national gross domestic product. Between 1972 and 2001, 588 900 ha (c. 20% of the forests) were deforested. Deforestation has been accelerating, reaching >28 000 ha yr−1 after 1997. The initial deforestation was associated with black bean cultivation following an increase in rainfall during the 1970s. In the 1980s, high soybean prices stimulated further deforestation. Finally, the introduction of soybean transgenic cultivars in 1997 reduced plantation costs and stimulated a further increase in deforestation. The domestic economy had little association with deforestation. Although deforestation was more intense in the moister (rainfall >600 mm yr−1) areas, more than 300 000 ha have already been deforested in the drier areas, suggesting that climatic limitations are being overcome by technological and genetic improvement. Furthermore, more than 300 000 ha of forest occur in sectors without major soil and rainfall limitations. If global trends of technology, soybean markets and climate continue, and no active conservation policies are applied, vast areas of the Chaco will be deforested in the coming decades.

An inverse relationship between moisture and grazing intensity in an arid mountain-basin system

2021 ◽  
pp. 030913332110600
Author(s):  
Jun Zhang ◽  
Xiao-zhong Huang ◽  
Jia-le Wang ◽  
Richard HW Bradshaw ◽  
Tao Wang ◽  
...  
Keyword(s):  
Arid Region ◽  
Influencing Factor ◽  
Regional Climate ◽  
Fungal Spores ◽  
Grazing Intensity ◽  
Pollen Grains ◽  
High Mountains ◽  
Spores And Pollen ◽  
The North ◽  
Basin System

Precipitation has been suggested as a crucial influencing factor in the primary productivity in arid and semi-arid regions, yet how moisture fluctuation in an arid mountain-basin system of the north Qinghai–Tibetan Plateau has affected human activities is poorly understood. Here, we reconstruct the variations of grazing intensity in high elevations and regional humidity based on independent and high-resolution records of Sporormiella-type coprophilous fungal spores and pollen grains in the same well-dated sediment core from Lake Tian’E in the western Qilian Mountains over the past 3500 years. We find that stronger grazing activity was associated with low regional effective moisture, and propose that the drier regional climate pushed people and their livestock into the mountainous areas. A notable exception was a reduction of human and grazing activities in arid region with high mountains during 380–580 CE caused by centennial-length dry and cold conditions. In addition, it is also noteworthy that intensified grazing activity occurred during 580–720 CE and after ∼1920 CE, corresponding to a warmer and wetter climate and diverse subsistence strategies with social developments in the lowlands of the Hexi Corridor. Our findings potentially provide a historical reference for understanding how ancient people adapted to the climate change in arid region with high mountains.

scholarly journals Different levels of shade on population of grasshoppers and its oviposition preference on heliconias

2018 ◽  
Vol 48 (2) ◽  
Author(s):  
Ana Cristina Bittar ◽  
Elen de Lima Aguiar-Menezes ◽  
José Guilherme Marinho Guerra ◽  
Janaína Ribeiro Costa Rouws ◽  
Luiz Augusto de Aguiar ◽  
...  
Keyword(s):  
Block Design ◽  
Oviposition Preference ◽  
Production Parameters ◽  
Lateral Buds ◽  
Randomized Block Design ◽  
Light Requirements ◽  
Four Levels ◽  
Preferred Species ◽  
Different Levels

ABSTRACT: Grasshoppers of the families Acrididae and Romaleidae (Orthoptera) are among the insects that defoliate heliconias and have been gaining status as pests of commercial crops of these plants in Brazil. The objectives of the present study were to identify the grasshopper defoliating heliconias in the municipality of Santo Antônio de Pádua, RJ (Brazil), to evaluate the effect of different levels of shade on the population of this grasshopper and the production parameters of heliconias, and to determine if this grasshopper has an oviposition preference among the heliconias evaluated. The experiment was in a completely randomized block design, in subdivided plots (four levels of shade in the plot, 0%, 30%, 50% and 80%, and four species of Heliconia: H. psittacorum, H. stricta, H. wagneriana and H. psittacorum x H. spathocircinata ‘Golden Torch’ in the subplot), with four replications. The grasshopper was identified as Cornops frenatum frenatum (Acrididae). An increase in shade resulted in a decrease in the number of oviposition holes from the grasshopper and the number of lateral buds. Shade did not influence the number of C. f. frenatum nymphs and adults and the number of flower stems. H. wagneriana was the most preferred species for oviposition by C. f. frenatum. Results suggested using screens to shade heliconia plants can help control C. f. frenatum populations, however, the light requirements of the heliconias should be considered to guarantee productivity.

Boys' circumcision and girls' puberty rites among the Swahili of Mafia Island, Tanzania

Africa ◽  
1976 ◽  
Vol 46 (1) ◽  
pp. 21-33 ◽  
Author(s):  
A. P. Caplan
Keyword(s):  
The Political ◽  
The North ◽  
Political Implications ◽  
Opening Paragraph ◽  
Different Levels

Opening ParagraphIn the north of Mafia Island, the rites surrounding the circumcision of boys and the first menstruation of girls are no longer, if indeed they ever were, universally performed. This article attempts to explain this situation, and in so doing, draws on some of Turner's work on symbolism. In particular, his distinction between different levels of meaning expressed by symbols—the exegetical, the operational and the positional (1962)—is followed in a discussion of the political implications of performance or rejection of the rites.

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