Savanna-derived organic matter remaining in arable soils of the South African Highveld long-term mixed cropping: Evidence from 13C and 15N natural abundance

The aim of the article is to assess the average long-term background hydrochemical input of chemical elements and organic matter from the flows of the natural component of the environment "Rivers" flowing into the South, Selenginsky, Middle and North reservoirs of Lake. Baikal. The results of calculation of the average annual amount (g/year) of chemical elements and organic matter (Na+, K+, Ca2+, Mg2+, Al, Si, Mn2+, Feобщ , SO42-, HCO3-, Cl-, NO3-, PO43-, Cr, Cu, Cd, Hg, Pb, Sr, Zn, Co, U, V, Mo, Cорг, Nорг, Pорг, Sорг, CO2, Ti) in the streams of the natural component of the environment "Rivers" flowing into the South, Selenginsky, Sredniy, Severny reservoirs of Lake Baikal are presented. The scale of the river chemical input into the reservoirs and the contribution of the "River" flows to the chemical balances of these reservoirs have been determined. It has been established that only in the Selenga reservoir the rivers carry a significant amount of matter (about 3%). The contribution of river flows to the chemical balance of the reservoir is 3.54; 5.4; 17.5 and 21.5% in the South, Selenga, Middle and North reservoirs, respectively. The rivers flowing into the Selenga reservoir carry 70.6% of the total amount of matter brought by the rivers into the lake. Whereas the rivers of the Northern, Middle and Southern reservoirs carry 14.0; 11.6 and 3.8% of the matter. Only in the Selenga and Northern reservoirs, the rivers (tributaries) are the main sources of macrocomponents (K+, Na+, Ca2+, SO42-, CO3-, Cl-), a number of microcomponents (Rb, Mo, Hg, Sr, and Cu and Zn in the Selenga river-), organic matter (Corgг, Norg, Porg), and biogenic components in the Selenga reservoir (NO3-).

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Heterogeneity and Instability: Theoretical–Methodological Outcomes of Three Investigations on Land and Agrarian Movements and the State

Agrarian South Journal of Political Economy ◽

10.1177/22779760211052612 ◽

2021 ◽

pp. 227797602110526

Author(s):

Marcelo C. Rosa ◽

Camila Penna ◽

Priscila D. Carvalho

Keyword(s):

South African ◽

Agrarian Reform ◽

The State ◽

Agricultural Workers ◽

The South ◽

The Third ◽

Public Expression ◽

Transnational Ties ◽

Definition Of

The article presents a theoretical–methodological proposal to research movements and its connections based on the associations they establish. The first investigation focuses on the transformations of the South African Landless People’s Movement, the second on interactions between Brazilian rural movements and the National Institute of Colonization and Agrarian Reform, the third focuses on the transnational ties of the Brazilian National Confederation of Agricultural Workers. We produce an ontological definition of movements and the state as collectives whose existence is defined by continuous assemblages of heterogeneous and unstable elements. Those collectives are not enclosed analytical units, but contingent and contextual. Methodologically, we suggest the observation of the processes in the long term to grasp the continuous constructions of those collectives, even before they reach public expression. Controversies are analytical categories for understanding which elements allow things to take the course we analyze.

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Long-Term Monitoring Of Cyclic Frequency Variability in Rapidly Oscillating ap Stars at the Sutherland Station of The South African Astronomical Observatory

The Impact of Long-Term Monitoring on Variable Star Research ◽

10.1007/978-94-011-1164-5_15 ◽

1994 ◽

pp. 185-196 ◽

Cited By ~ 1

Author(s):

D. W. Kurtz ◽

Peter Martinez

Keyword(s):

South African ◽

Astronomical Observatory ◽

The South ◽

Cyclic Frequency ◽

Long Term Monitoring ◽

Ap Stars ◽

Term Monitoring

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Soil structure after 18 years of long-term different tillage systems and fertilisation in Haplic Luvisol

Soil and Water Research ◽

10.17221/38/2017-swr ◽

2018 ◽

Vol 13 (No. 3) ◽

pp. 140-149 ◽

Cited By ~ 1

Author(s):

Šimanský Vladimír ◽

Lukáč Martin

Keyword(s):

Organic Matter ◽

Soil Structure ◽

Management Practices ◽

Crop Residues ◽

Organic Matter Content ◽

Matter Content ◽

Soil Tillage ◽

Arable Soils ◽

Water Stable Aggregates

Soil structure is a key determinant of many soil environmental processes and is essential for supporting terrestrial ecosystem productivity. Management of arable soils plays a significant role in forming and maintaining their structure. Between 1994 and 2011, we studied the influence of soil tillage and fertilisation regimes on the stability of soil structure of loamy Haplic Luvisol in a replicated long-term field experiment in the Dolná Malanta locality (Slovakia). Soil samples were repeatedly collected from plots exposed to the following treatments: conventional tillage (CT) and minimum tillage (MT) combined with conventional (NPK) and crop residue-enhanced fertilisation (CR+NPK). MT resulted in an increase of critical soil organic matter content (St) by 7% in comparison with CT. Addition of crop residues and NPK fertilisers significantly increased St values (by 7%) in comparison with NPK-only treatments. Soil tillage and fertilisation did not have any significant impact on other parameters of soil structure such as dry sieving mean weight diameters (MWD), mean weight diameter of water-stable aggregates (MWDWSA), vulnerability coefficient (Kv), stability index of water-stable aggregates (Sw), index of crusting (Ic), contents of water-stable macro- (WSAma) and micro-aggregates (WSAmi). Ic was correlated with organic matter content in all combinations of treatments. Surprisingly, humus quality did not interact with soil management practices to affect soil structure parameters. Higher sums of base cations, CEC and base saturation (Bs) were linked to higher Sw values, however higher values of hydrolytic acidity (Ha) resulted in lower aggregate stability in CT treatments. Higher content of K+ was responsible for higher values of MWDWSA and MWD in CT. In MT, contents of Ca2+, Mg2+ and Na+ were significantly correlated with contents of WSAmi and WSAma. Higher contents of Na+ negatively affected St values and positive correlations were detected between Ca2+, Mg2+ and Na+ and Ic in NPK treatments.

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The South African Cash-In-Transit Heist Enterprise: Managing its Wellspring and Concatenation

International Annals of Criminology ◽

10.1017/cri.2020.11 ◽

2019 ◽

Vol 57 (1-2) ◽

pp. 198-224

Author(s):

Mahlogonolo Stephina Thobane

Keyword(s):

South African ◽

The South ◽

The Public ◽

Reduction Strategies ◽

Career Criminals ◽

Risk Reduction Strategies ◽

Master Of Arts ◽

In Transit ◽

Method Approach

AbstractSouth African cash-in-transit (CIT) robberies appear to be in a state of flux. According to the Minister of Police, Mr Bheki Cele, the incidence of these crimes has steadily decreased due to rapid response by the police in arresting more than 200 suspects between June and November 2018. Given the rhizomatic, eclectic nature of this crime type – and possible mechanical linkages and/or linear causality within the genesis of the crime – it is debatable whether arrests and incarceration offer a long-term solution. CIT robbers interviewed for this study reported that they were career criminals, less likely to be rehabilitated and that incarceration was only an interruption to their career. These findings were backed by life-course theories. This article contends that if the South African Criminal Justice System wants to curb CIT robberies, an investigation into proactive methods for combating the crime should be developed and risk reduction strategies crafted. After investigating possible causes of CIT robberies, this research made recommendations based on holistic measures involving the public, family, and various government and non-governmental departments. The research was conducted for a Master of Arts degree in Criminology. A mixed-method approach was followed and 40 incarcerated offenders who committed robbery with aggravating circumstances participated in the study.

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The South African Political Process

Government and Opposition ◽

10.1111/j.1477-7053.1991.tb01143.x ◽

1991 ◽

Vol 26 (3) ◽

pp. 316-328 ◽

Cited By ~ 1

Author(s):

J. E. Spence

Keyword(s):

South African ◽

Political Process ◽

The South ◽

African Government ◽

International Pressure ◽

Economic Forces ◽

South African Politics ◽

To Receive ◽

Opposition Parties

Over a quarter of a century ago i was privileged to receive an invitation to contribute an article on South African politics to the first number of this journal. I recall dismissing the thesis that ‘economic forces, together with the emergence of an African middle class, will provide a long term solution to the country's problems…’ I argued thateven if we assume a lessening in international pressure, and an indefinite coqtinuation of the Republic's economic expansion, the [black] elite thrown up by this process may present the South African government (and the opposition parties) with their most fundamental challenge. In these circumstances — the most favourable South Africa can legitimately expect — the choice will still lie between yet more authoritarian methods of social control and a widening of the area of participation in the political process on terms distinctly more radical than those currently envisaged by the two major opposition parties in the Parliament based on the present electorate.

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