Conservation agriculture improves adaptive capacity of cropping systems to climate stress in Malawi

Conservation agriculture (CA) including reduced or no-tillage and crop residue retention, is known to be a self–sustainable system as well as an alternative to residue burning. The present study evaluated the effect of reduced tillage coupled with residue retention under different cropping systems on soil properties and crop yields in a Vertisol of a semiarid region of central India. Two tillage systems – conventional tillage (CT) with residue removed, and reduced tillage (RT) with residue retained – and six major cropping systems of this region were examined after 3 years of experimentation. Results demonstrated that soil moisture content, mean weight diameter, percent water stable aggregates (>0.25mm) for the 0–15cm soil layer were significantly (Pmoderately labile>less labile. At the 0–15cm depth, the contributions of moderately labile, less labile and non-labile C fractions to total organic C were 39.3%, 10.3% and 50.4% respectively in RT and corresponding values for CT were 38.9%, 11.7% and 49.4%. Significant differences in different C fractions were observed between RT and CT. Soil microbial biomass C concentration was significantly higher in RT than CT at 0–15cm depth. The maize–chickpea cropping system had significantly (P–1 followed by soybean+pigeon pea (2:1) intercropping (3.50 t ha–1) and soybean–wheat cropping systems (2.97 t ha–1). Thus, CA practices could be sustainable management practices for improving soil health and crop yields of rainfed Vertisols in these semiarid regions.

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The crucial role of mulch to enhance the stability and resilience of cropping systems in southern Africa

Agronomy for Sustainable Development ◽

10.1007/s13593-021-00687-y ◽

2021 ◽

Vol 41 (2) ◽

Author(s):

Blessing Mhlanga ◽

Laura Ercoli ◽

Elisa Pellegrino ◽

Andrea Onofri ◽

Christian Thierfelder

Keyword(s):

Crop Rotation ◽

Southern Africa ◽

Cropping Systems ◽

Conservation Agriculture ◽

Conventional Tillage ◽

Yield Stability ◽

No Tillage ◽

The Stability ◽

Stability And Resilience

AbstractConservation agriculture has been promoted to sustainably intensify food production in smallholder farming systems in southern Africa. However, farmers have rarely fully implemented all its components, resulting in different combinations of no-tillage, crop rotation, and permanent soil cover being practiced, thus resulting in variable yield responses depending on climatic and soil conditions. Therefore, it is crucial to assess the effect of conservation agriculture components on yield stability. We hypothesized that the use of all three conservation agriculture components would perform the best, resulting in more stable production in all environments. We evaluated at, eight trial locations across southern Africa, how partial and full implementation of these components affected crop yield and yield stability compared with conventional tillage alone or combined with mulching and/or crop rotation. Grain yield and shoot biomass of maize and cowpea were recorded along with precipitation for 2 to 5 years. Across different environments, the addition of crop rotation and mulch to no-tillage increased maize grain by 6%, and the same practices added to conventional tillage led to 13% yield increase. Conversely, adding only mulch or crop rotation to no-tillage or conventional tillage led to lower or equal maize yield. Stability analyses based on Shukla’s index showed for the first time that the most stable systems are those in which mulch is added without crop rotation. Moreover, the highest yielding systems were the least stable. Finally, additive main effects and multiplicative interaction analysis allowed clarifying that mulch added to no-tillage gives stable yields on sandy soil with high rainfall. Similarly, mulch added to conventional tillage gives stable yield on sandy soil, but under low rainfall. This is the first study that highlighted the crucial role of mulch to enhance the stability and resilience of cropping systems in southern Africa, supporting their adaptability to climate change.

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Earthworm Inoculation Improves Upland Rice Crop Yield and Other Agrosystem Services in Madagascar

Agriculture ◽

10.3390/agriculture11010060 ◽

2021 ◽

Vol 11 (1) ◽

pp. 60

Author(s):

Onja Ratsiatosika ◽

Malalatiana Razafindrakoto ◽

Tantely Razafimbelo ◽

Michel Rabenarivo ◽

Thierry Becquer ◽

...

Keyword(s):

Upland Rice ◽

Cropping Systems ◽

Conservation Agriculture ◽

Biological Properties ◽

Rice Grain ◽

Positive Effects ◽

Ecological Transition ◽

Earthworm Activity ◽

Endogeic Earthworms ◽

Plant Properties

The effects of earthworm inoculation and cropping systems on upland rice systems were examined over a four-year period in the Highlands of Madagascar. Each year, endogeic earthworms Pontoscolex corethrurus (Rhinodrilidae) were inoculated (EW+) at a density of 75 ind m−2 or were not inoculated (EW0). Inoculation was tested in three cropping systems: conservation agriculture (CA) and traditional tillage with or without residues restitution. Soil and plant properties were measured during the first three years while soil biological properties were assessed at the fourth year. At the end of the experiment, earthworm density was three-fold higher in EW+ than in EW0, demonstrating the success of the inoculation. Earthworm density was more important in CA than in tillage systems. Earthworm inoculation had higher significant effects on soil and plant properties than cropping systems. Earthworm inoculation had positive effects on soil macroaggregation (+43%), aboveground biomass (+27%), rice grain yield (+45%), and N grain amount (+43%). Intensifying earthworm activity in field conditions to meet the challenge of ecological transition is supported by our study.

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Effects of conservation agriculture on productivity and Economics of maize-wheat based cropping systems in midwestern Nepal

SAARC Journal of Agriculture ◽

10.3329/sja.v17i1.42761 ◽

2019 ◽

Vol 17 (1) ◽

pp. 49-63

Author(s):

K Pariyar ◽

A Chaudhary ◽

P Sapkota ◽

S Sharma ◽

CB Rana ◽

...

Keyword(s):

Grain Yield ◽

Cropping Systems ◽

Cropping System ◽

Conservation Agriculture ◽

Crop Productivity ◽

Conventional Tillage ◽

Net Income ◽

Zero Tillage ◽

Higher Plant ◽

Equivalent Yield

The effects of two tillage methods (zero tillage and conventional tillage), two residue managements (residue kept and residue removed) and two levels of cropping system (maize + soybean and sole maize) were studied over 3 years (2015-2017) at Dailekh district of Nepal. Arun-2 and Puja were the varieties of maize and soybean used respectively, followed by winter wheat. The results revealed that the maize + soybean system had significantly higher plant population and ear population (34.83 thousands ha-1 and 34.35 thousands ha-1, respectively), grains per row (37.1), ear length (16.6 cm) and 20.5% higher grain yield as compared to sole maize. The highest maize equivalent yield (7.92 t ha-1) was recorded in maize + soybean as compared to the lower grain yield equivalent (7.06 t ha-1) in sole maize. Zero tillage accounted relatively higher benefits (high net income and B:C ratio) as compared to conventional tillage. The residue kept plot resulted significantly higher B:C ratio (2.41) than the residue removed (2.11) and the maize + soybean recorded 82.5% greater B:C ratio compared to sole maize. Net annual income was significantly higher in zero tillage, residue kept and maize + soybean system (NRs. 223072.00, 222958.00 and 269016.00 ha-1 respectively). Such combinations are recommended for Dailekh district of Nepal to have profitable crop productivity. SAARC J. Agri., 17(1): 49-63 (2019)

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Conservation agriculture enhances resistance of maize to climate stress in a Malawian medium-term trial

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2018.07.009 ◽

2019 ◽

Vol 277 ◽

pp. 95-104 ◽

Cited By ~ 6

Author(s):

Peter R. Steward ◽

Christian Thierfelder ◽

Andrew J. Dougill ◽

Ivy Ligowe

Keyword(s):

Conservation Agriculture ◽

Medium Term ◽

Climate Stress ◽

Term Trial

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Practices of conservation agriculture prevail over cropping systems and landscape heterogeneity in understanding the ecosystem service of aphid biocontrol

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2017.08.005 ◽

2017 ◽

Vol 249 ◽

pp. 70-79 ◽

Cited By ~ 11

Author(s):

Ariane Chabert ◽

Jean-Pierre Sarthou

Keyword(s):

Ecosystem Service ◽

Landscape Heterogeneity ◽

Cropping Systems ◽

Conservation Agriculture ◽

Aphid Biocontrol

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Seed germination ecology of Conyza stricta Willd. and implications for management

PLoS ONE ◽

10.1371/journal.pone.0244059 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0244059

Author(s):

Safdar Ali ◽

Fakhar Din Khan ◽

Rehmat Ullah ◽

Rahmat Ullah Shah ◽

Saud Alamri ◽

...

Keyword(s):

Seed Germination ◽

Osmotic Potential ◽

Cropping Systems ◽

Seedling Emergence ◽

Management Strategies ◽

Conservation Agriculture ◽

Weed Species ◽

Seed Burial ◽

Germination Ecology ◽

Tillage Practices

Numerous cropping systems of the world are experiencing the emergence of new weed species in response to conservation agriculture. Conyza stricta Willd. is being a newly emerging weed of barley-based cropping systems in response to conservational tillage practices. Seed germination ecology of four populations (irrigated, rainfed, abandoned and ruderal habitats) was studied in laboratory and greenhouse experiments. The presence/absence of seed dormancy was inferred first, which indicated seeds were non-dormant. Seed germination was then recorded under various photoperiods, constant and alternating day/night temperatures, and pH, salinity and osmotic potential levels. Seedling emergence was observed from various seed burial depths. Seeds of all populations proved photoblastic and required 12-hour light/dark period for germination. Seeds of all populations germinated under 5–30°C constant temperature; however, peak germination was recorded under 17.22–18.11°C. Nonetheless, the highest germination was noted under 20/15°C alternating day/night temperature. Ruderal and irrigated populations better tolerated salinity and germinated under 0–500 mM salinity. Similarly, rainfed population proved more tolerant to osmotic potential than other populations. Seeds of all populations required neutral pH for the highest germination, whereas decline was noted in germination under basic and alkaline pH. Seedling emergence was retarded for seeds buried >2 cm depth and no emergence was recorded from >4 cm depth. These results add valuable information towards our understanding of seed germination ecology of C. stricta. Seed germination ability of different populations under diverse environmental conditions suspects that the species can present severe challenges in future if not managed. Deep seed burial along with effective management of the emerging seedlings seems a pragmatic option to manage the species in cultivated fields. However, immediate management strategies are needed for rest of the habitats.

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Bioactive Properties of Fruits and Leafy Vegetables Managed with Integrated, Organic, and Organic No-Tillage Practices in the Mediterranean Area: A Two-Year Rotation Experiment

Agronomy ◽

10.3390/agronomy10060841 ◽

2020 ◽

Vol 10 (6) ◽

pp. 841 ◽

Cited By ~ 2

Author(s):

Costanza Ceccanti ◽

Marco Landi ◽

Daniele Antichi ◽

Lucia Guidi ◽

Luigi Manfrini ◽

...

Keyword(s):

Bioactive Compounds ◽

Environmental Sustainability ◽

Management Practices ◽

Cropping Systems ◽

Cropping System ◽

Conservation Agriculture ◽

Leafy Vegetables ◽

No Tillage ◽

Cash Crops ◽

Starting Point

The sustainability of current farming systems has been questioned in the last decades, especially in terms of the environmental impact and mitigation of global warming. Also, the organic sector, which is supposed to impact less on the environment than other more intensive systems, is looking for innovative solutions to improve its environmental sustainability. Promisingly, the integration of organic management practices with conservation agriculture techniques may help to increase environmental sustainability of food production. However, little is known about the possible impact of conservation agriculture on the content of bioactive compounds in cash crops. For this reason, a two-year rotation experiment used 7 cash crops (4 leafy vegetables and 3 fruit crops) to compare integrated (INT), organic farming (ORG), and organic no-tillage (ORG+) systems to evaluate the possible influence of cropping systems on the nutritional/nutraceutical values of the obtained fruits and leafy vegetables. The results pointed out specific responses based on the species as well as the year of cultivation. However, cultivation with the ORG+ cropping system resulted in effective obtainment of fruits and vegetables with higher levels of bioactive compounds in several cases (11 out 16 observations). The ORG+ cropping system results are particularly promising for leafy vegetable cultivation, especially when ORG+ is carried out on a multi-year basis. Aware that the obtained data should be consolidated with longer-term experiments, we conclude that this dataset may represent a good starting point to support conservation agriculture systems as a possible sustainable strategy to obtain products with higher levels of bioactive compounds.

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Modeling Soil Nitrate Accumulation and Leaching in Conventional and Conservation Agriculture Cropping Systems

Water ◽

10.3390/w12061571 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1571

Author(s):

Nicolò Colombani ◽

Micòl Mastrocicco ◽

Fabio Vincenzi ◽

Giuseppe Castaldelli

Keyword(s):

Nitrate Leaching ◽

Cropping Systems ◽

Model Performance ◽

Agricultural Practices ◽

Conservation Agriculture ◽

Nitrate Accumulation ◽

Matric Potential ◽

Tillage Practices ◽

Compost Amendment ◽

Before And After

Nitrate is a major groundwater inorganic contaminant that is mainly due to fertilizer leaching. Compost amendment can increase soils’ organic substances and thus promote denitrification in intensively cultivated soils. In this study, two agricultural plots located in the Padana plain (Ferrara, Italy) were monitored and modeled for a period of 2.7 years. One plot was initially amended with 30 t/ha of compost, not tilled, and amended with standard fertilization practices, while the other one was run with standard fertilization and tillage practices. Monitoring was performed continuously via soil water probes (matric potential) and discontinuously via auger core profiles (major nitrogen species) before and after each cropping season. A HYDRUS-1D numerical model was calibrated and validated versus observed matric potential and nitrate, ammonium, and bromide (used as tracers). Model performance was judged satisfactory and the results provided insights on water and nitrogen balances for the two different agricultural practices tested here. While water balance and retention time in the vadose zone were similar in the two plots, nitrate leaching was less pronounced in the plot amended with compost due to a higher denitrification rate. This study provides clear evidence that compost addition and no-tillage (conservation agriculture) can diminish nitrate leaching to groundwater, with respect to standard agricultural practices.

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