Assessing the Effects of Water Management Regimes and Rice Residue on Growth and Yield of Rice in Uganda

2015 ◽  
Vol 7 (2) ◽  
pp. 141-149 ◽  
Author(s):  
T. Awio ◽  
B. Bua ◽  
J. Karungi
Keyword(s):  
Water Management ◽  
Growth And Yield ◽  
Management Regimes

Reducing drainage water phosphorus concentration with rice cultivation under different water management regimes

2018 ◽  
Vol 205 ◽  
pp. 30-37 ◽  
Author(s):  
Mohsen Tootoonchi ◽  
Jehangir H. Bhadha ◽  
Timothy A. Lang ◽  
J. Mabry McCray ◽  
Mark W. Clark ◽  
...  
Keyword(s):  
Water Management ◽  
Drainage Water ◽  
Rice Cultivation ◽  
Phosphorus Concentration ◽  
Management Regimes

scholarly journals Financial and risk analysis of African mahogany plantations in Brazil

2018 ◽  
Vol 42 (2) ◽  
pp. 148-158
Author(s):  
Andressa Ribeiro ◽  
Carolina Souza Jarochinski e Silva ◽  
Antonio Carlos Ferraz Filho ◽  
José Roberto Soares Scolforo
Keyword(s):  
Interest Rates ◽  
Net Present Value ◽  
Financial Analysis ◽  
Initial Density ◽  
Growth And Yield ◽  
Financial Return ◽  
African Mahogany ◽  
Management Regimes ◽  
Wood Demand ◽  
Growth And Yield Modeling

ABSTRACT Wood demand is increasing in quality and quantity, and economic studies are fundamental to analyze the feasibility of forest projects. These researches are in line with management and silvicultural studies, highlighting growth and yield modeling. This paper proposes an economic evaluation of implementation of African mahogany stands in Brazil under different perspectives of forest management. Data are from plantations ranging from 1.1 to 15 years old in different Brazilian regions. Financial analysis was undertaken using Net Present Value (NPV), Internal Rate of Return (IRR) and Equal Annual Equivalent (EAE) for a 20-year period considering three thinning management regimes (A - unthinned, B - one thinning at age 10 years remaining 150 trees ha-1 and C - two thinnings, first at age 8 remaining 150 trees ha-1 and second at age 15 years remaining 75 trees ha-1) considering an initial density of 278 trees ha-1. A Monte Carlo simulation was performed considering six risk variables. Results showed that the discount rate is the variable that most influences the viability of the project. All site indexes in all management regimes lead to a feasible financial return, with NPV values ranging from 25,053 to 125,780 Brazilian reais per hectare, being regimes B and C the best ones. The probability for an unfeasible investment is almost zero, highlighting African mahogany as a great forest investment opportunity, providing high interest rates values (14% to 25%), superior to most available market rates of return.

scholarly journals Effect of intercropping madumbe (Colocasia esculenta) and rice (Oryza sativa L.) on yield and land productivity under different irrigation water management techniques with effluent water

Water SA ◽  
2020 ◽  
Vol 46 (2 April) ◽  
Author(s):  
TI Busari ◽  
A Senzanje ◽  
AO Odindo ◽  
CA Buckley
Keyword(s):  
Water Management ◽  
Irrigation Water ◽  
Block Design ◽  
Irrigation Management ◽  
Growth And Yield ◽  
Rice Grain ◽  
Land Productivity ◽  
Irrigation Water Management ◽  
Sole Cropping ◽  
Management Techniques

The need for the optimal use of land, without a yield penalty, in urban and peri-urban (UP) settlements is vital. This study investigated the effect of intercropping madumbe and rice with respect to yield and land productivity when irrigated with anaerobic baffled reactor (ABR) effluent under different irrigation water management techniques. It was hypothesized that intercropping under different irrigation water management techniques has no effect on the yield and land productivity. Field trials were conducted in the 2017 and 2018 cropping seasons with ABR effluent (without fertilizer) at the Newlands Mashu Experimental Site, Newlands East, Durban, South Africa. A randomized complete block design with 3 replications; cropping treatments of sole madumbe, sole rice and madumbe + rice (intercrop) and irrigation treatments of alternate wetting and drying (AWD), continuous flood irrigation (CFI) and wetting without flooding (WWF) was used. Growth and yield parameters at harvest were determined. Thereafter, land equivalent ratio (LER) was calculated to evaluate the productivity of the intercrop. The effect of intercropping was significant (P < 0.05) on the total number of irrigation events and total water use. There was a significant reduction (P < 0.05) in plant heights of both madumbe and rice at intercrop. However, the effect on plant height for treatment CFI was positive but not significant (P > 0.05) for both seasons. A significant (P < 0.05) reduction also occurred in the number of madumbe leaves/plant, and panicles/plant and tillers/plant for rice. Intercropping significantly reduced (P < 0.05) madumbe corm and rice grain yield over the two seasons relative to sole cropping.  LER showed that intercropping madumbe with rice was not more productive (LER < 1) than sole cropping of madumbe. It was concluded that over the two-season period, intercropping madumbe and rice do not yield appreciably under any of the three irrigation management techniques applied and the study hypothesis is thus rejected.

scholarly journals Effect of intercropping madumbe (Colocasia esculenta) and rice (Oryza sativa L.) on yield and land productivity under different irrigation water management techniques with effluent water

Water SA ◽  
2020 ◽  
Vol 46 (2 April) ◽  
Author(s):  
TI Busari ◽  
A Senzanje ◽  
AO Odindo ◽  
CA Buckley
Keyword(s):  
Water Management ◽  
Irrigation Water ◽  
Block Design ◽  
Irrigation Management ◽  
Growth And Yield ◽  
Rice Grain ◽  
Land Productivity ◽  
Irrigation Water Management ◽  
Sole Cropping ◽  
Management Techniques

The need for the optimal use of land, without a yield penalty, in urban and peri-urban (UP) settlements is vital. This study investigated the effect of intercropping madumbe and rice with respect to yield and land productivity when irrigated with anaerobic baffled reactor (ABR) effluent under different irrigation water management techniques. It was hypothesized that intercropping under different irrigation water management techniques has no effect on the yield and land productivity. Field trials were conducted in the 2017 and 2018 cropping seasons with ABR effluent (without fertilizer) at the Newlands Mashu Experimental Site, Newlands East, Durban, South Africa. A randomized complete block design with 3 replications; cropping treatments of sole madumbe, sole rice and madumbe + rice (intercrop) and irrigation treatments of alternate wetting and drying (AWD), continuous flood irrigation (CFI) and wetting without flooding (WWF) was used. Growth and yield parameters at harvest were determined. Thereafter, land equivalent ratio (LER) was calculated to evaluate the productivity of the intercrop. The effect of intercropping was significant (P < 0.05) on the total number of irrigation events and total water use. There was a significant reduction (P < 0.05) in plant heights of both madumbe and rice at intercrop. However, the effect on plant height for treatment CFI was positive but not significant (P > 0.05) for both seasons. A significant (P < 0.05) reduction also occurred in the number of madumbe leaves/plant, and panicles/plant and tillers/plant for rice. Intercropping significantly reduced (P < 0.05) madumbe corm and rice grain yield over the two seasons relative to sole cropping.  LER showed that intercropping madumbe with rice was not more productive (LER < 1) than sole cropping of madumbe. It was concluded that over the two-season period, intercropping madumbe and rice do not yield appreciably under any of the three irrigation management techniques applied and the study hypothesis is thus rejected.

The transition toward resilient water management regimes: where are we now?

2021 ◽  
Author(s):  
Matteo Mannocchi
Keyword(s):  
Water Management ◽  
Integrated Management ◽  
Scientific Evidence ◽  
Rapid Assessment ◽  
Main Trend ◽  
Management Approach ◽  
Institutional Settings ◽  
Management Regime ◽  
Wide Range ◽  
Management Regimes

&lt;p&gt;Hydro-Meteorological Hazards (HMH) such as drought, floods and storm surge have always constituted a threat to social-ecological systems (SES) but, due to increasing uncertainties caused by climate and by rapidly changing socio-economic boundary conditions, it is necessary to step up effort to mitigate the risks. More attention should be devoted to understanding and managing the transition from traditional management regimes to more sustainable and resilient regimes that take into account environmental, technological, economic, institutional and cultural characteristics of river basins.&lt;/p&gt;&lt;p&gt;Since the 1990s many scholars, from both natural and social sciences, have urged to integrate knowledge and shed light on the functioning of the SESs in order to increase resilience to perturbances (Berkes and Folke 1998). As sustainability science is mainly a problem-driven and solution-oriented field that follows a transformational agenda (Lang 2012), it becomes evident that the nexus between environmental, political and institutional dimensions cannot be ignored to accelerate the path toward sustainability. &amp;#160;&lt;/p&gt;&lt;p&gt;There is consensus that the complex, non-linear and rather unpredictable nature of HMHs, exacerbated by climate change, should require a more adaptive (Armitage 2007), flexible and holistic (Holling 2002) management approach that can speed up and reinforce the learning loops to allow for more rapid assessment and implementation of the consequences of new insights and scientific evidence (Pahl Wostle 2007). Cooperation among a wide range of stakeholders with different knowledge, expertise and views is often indicated as a prerequisite to establish a resilient and adaptive water management regime (Olsson et al. 2004). These principles mainstreamed since the beginning of the 2000s and synthesized by concepts like &amp;#8220;co-management&amp;#8221;, &amp;#8220;adaptive and integrated management&amp;#8221;, or &amp;#8220;adaptive co-management&amp;#8221;, are the pillars of what is considered a paradigm shift in water management (Pahl Wostle and Nicola 2011) and have inspired institutional settings, policies, and practices.&lt;/p&gt;&lt;p&gt;However, the debate is still ongoing to determine at what stage of the transition we are in, whether the aforementioned principles have been adopted and translated into practices on a wide scale, and whether and how such practices have contributed to increasing the resilience of the SES. It will be critically examined the literature trying to identify the main trend of the last two decades. The review will be accompanied by the case-studies upon which theories have been built and tested.&lt;/p&gt;

Water management regimes alter Pb uptake and translocation in fragrant rice

2018 ◽  
Vol 149 ◽  
pp. 128-134 ◽  
Author(s):  
Umair Ashraf ◽  
Saddam Hussain ◽  
Nadeem Akbar ◽  
Shakeel Ahmad Anjum ◽  
Waseem Hassan ◽  
...  
Keyword(s):  
Water Management ◽  
Fragrant Rice ◽  
Management Regimes

A Density-Management Diagram for Slash Pine Plantations in the Lower Coastal Plain

1992 ◽  
Vol 16 (4) ◽  
pp. 178-185 ◽  
Author(s):  
Thomas J. Dean ◽  
Eric J. Jokela
Keyword(s):  
Coastal Plain ◽  
Pinus Elliottii ◽  
Slash Pine ◽  
Pine Plantations ◽  
Growth And Yield ◽  
Graphical Form ◽  
Annual Increment ◽  
Growing Stock ◽  
Management Regimes ◽  
Lower Coastal Plain

Abstract Data from 92 regional, midrotation-fertilizer trials were used to develop a density-management diagram for site-prepared slash pine (Pinus elliottii var. elliottii) plantations. The density-management diagram shows the interrelationships of five important stand variables (i.e., quadraticmean diameter (Dq), trees/ac, site height, standing volume/ac, and relative current annual increment) in a graphical form. The diagram can aid foresters in designing and comparing alternative density-management regimes for slash pine. In doing so, foresters can evaluate individualtree and stand level performances in relation to growing stock levels and make field approximations of growth and yield for various density-management regimes. Results indicated that fertilization and soil type had minimal effects on the diagram's isolines. This suggests broad applicabilityof the diagram for fertilized or unfertilized plantations found in the lower Coastal Plain. The use of the diagram is illustrated with three alternative density-management regimes, and a method is presented for estimating midrotation fertilization responses. South. J. Appl. For. 16(4):178-185

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