Effects Of Conservation Tillage Research Articles

Effect Of conservation tillage practices on aroma, yield and quality of mechanical-transplanting fragrant rice

ABSTRACT In our study, two popular fragrant rice cultivars (Meixiangzhan 2 and Xiangyaxiangzhan) were conducted by three treatments (CK: conventional tillage; T1: minimum tillage; T2: no-tillage) to assess the effects of conservation tillage on the aroma, yield and quality of mechanical-transplanting fragrant rice. Results depicted that the 2-acetyl-1-pyrroline (2-AP) content in mature grains of mechanical-transplanting fragrant rice remained high level under T1 and T2 treatments. 2-AP accumulation in mature grains was significant associated with the 2-AP, proline and pyrroline-5-carboxylic acid content, proline dehydrogenase and ornithine aminotransferase activity in grains and leaves during the grain-filling period. T1 and T2 treatments improved yield components, increased the photosynthetic matter accumulation, and increased yields. T1 and T2 treatments also resulted in a higher head milled rice rate and significant changes in protein content of mechanical-transplanting fragrant rice. Overall, conservation tillage practices were beneficial to increase the 2-AP content, quality and yield of mechanical-transplanting fragrant rice.

Effects of conservation and standard tillage on soil physico-chemical properties and overall quality in a semi-arid agrosystem

Context Shifting agricultural operations to more sustainable management practices is needed in the face of a changing climate. Aims In this study, the short-term effects of three tillage systems (no tillage, minimum tillage and conventional tillage) on a wide selection of soil properties in a semi-arid agrosystem of eastern Tunisia were assessed. Methods The studied soil properties included saturation percentage, bulk density, penetration resistance, mean weight diameter, electric conductivity, soil reaction, soil organic matter, carbonates, available phosphorus and exchangeable potassium. The impacts of tillage systems on soil quality indices (SQI) developed based on the total set of properties (SQI-T), or a minimum set (SQI-M) selected through principal component analysis, were also investigated. Key results Relative to conventional tillage, no tillage increased bulk density, penetration resistance and electrical conductivity, whereas minimum tillage affected only saturation percentage and pH. No tillage and minimum tillage did not enhance soil quality relative to conventional tillage. The SQI-T and SQI-M were highly correlated (r = 0.93) to each other suggesting that the outcomes of the two indices are comparable. Principal component analysis efficiently selected the most influential indicators of the effects of tillage systems on soil quality. Conclusions and implications Farmers in the study region are encouraged to consider minimum tillage during the early years of transition from standard to no tillage systems to avoid rapid decline in soil quality and consequent yield loss.

Effect of Conservation Tillage on Yield and Economics of Fodder Crops

In order to find out the efficacy of conservation tillage on yield and economics of fodder crops over conventional tillage in new alluvial zone of West Bengal, a field experiment was conducted at Central Research Farm, Gayeshpur, West Bengal, India during summer season of 2016 and 2017 comprising 3 tillage practices (T1: zero tillage, T2: minimum tillage, T3: conventional tillage) in main plot and 4 fodder crops (C1: maize, C2: sorghum, C3: rice bean, C4: cowpea) in subplot and replicated thrice in a split plot design. Mean data confirmed the superiority of conservation tillage over conventional tillage in improving soil status and thereby, crop performance. Cereal crop maize when grown under zero tillage produced highest green forage yield (42.33 t/ha), dry matter yield (7.84 t/ha). However, regarding crude protein yield, cowpea showed superiority over others specially when grown under zero tillage condition (1.071 t/ha). Mean data also stated that legume crops under conservation tillage remained economically more viable than cereal crops. Specifically, cultivation of cowpea under zero tillage condition was economically most profitable (B:C of 2.21) and therefore can be recommended in this region.

Effects of conservation tillage on wheat growth duration and grain yield in the North China Plain

ABSTRACT Low wheat grain yield under conservation tillage has been reported, and growth duration could determine the yield. Thus, an 11-year field experiment was conducted to assess the relationship between growth duration and grain yield under different tillage and residue managements. Four treatments were investigated: no-till with residue removal (NT0), conventional tillage with residue removal (CT0), no-till with residue retention (NTR, conservation tillage), and conventional tillage with residue incorporation (CTR). Beginning at 20 days after anthesis (DAA), NTR significantly increased physiological activities, indicating that NTR had a longer growth duration. NTR significantly prolonged growth duration by 2–3 days compared with the other treatments attributed to delayed emergence of seedlings caused by higher soil compaction and moisture under NTR. The CT0 had the highest grain yield on the standard harvest date used in the local area (36 DAA). Whereas the plants in NTR reached physiological maturity (39 DAA), the grain yield in NTR was significantly increased by 7.8–8.8% compared with yield at 36 DAA, and no significant difference was observed between NTR and CT0 due to the increased thousand kernel weight of NTR. Thus, it is practicable for harvesting at physiological maturity in NTR to obtain higher grain yield.

Conservation Tillage, Residue Management, and Crop Rotation Effects on Soil Major and Micro-nutrients in Semi-arid Vertisols of India

Due to declining soil quality and increasing climate change, resource conservation technologies are often advocated for the food production system. Conservation agriculture (CA) is one of the technologies that increase soil nutrient status without jeopardizing the soil health and quality. The effects of conservation tillage, residue retention, and cropping systems on soil physical, chemical, and biological properties within the irrigated agricultural system are well established. However, scanty information is available on the combined impact of tillage, residue, and cropping system available on the major and micro-nutrient in the rainfed farming systems. Thus, a field experiment was conducted to measure the short-term effect of CA practices on soil properties and major (N, P, and K) and micro (Fe, Mn, Zn, and Cu)-nutrients in a Vertisol of Central India. The field experiment was laid out in a split-plot design consisting of two tillage systems (TS), conventional tillage (CT) and reduced tillage (RT), as the main plots and six cropping systems (CS) as subplots. A total of 144 soil samples were collected after four crop cycles to assess soil properties and nutrient (major and micro-nutrient) status. Results demonstrated that in the surface soil layer (0–5 cm), the major and micro-nutrient concentrations were higher than subsurface layers, regardless of TS and CS. In the surface soils, soil organic carbon (SOC) varied from 0.58 to 0.60% under CT and from 0.60 to 0.62% under RT. Tillage and cropping systems had a significant effect (p < 0.05) on major available nutrients (N, P, and K) at 0–5-cm depth. The DTPA extractable Fe, Mn, Cu, and Zn concentrations exhibited decreasing trends with increasing depth. At 0–5-cm depth, the DTPA-Fe, Mn, Cu, and Zn under CT varied from 7.56 to 9.58 mg kg−1, 15.04 to 15.91 mg kg−1, 1.37 to 1.80 mg kg−1, and 0.57 to 0.62 mg kg−1 and under RT varied from 8.25 to 11.16 mg kg−1, 15.65 to 17.73 mg kg−1, 1.54 to 1.80 mg kg−1, and 0.59 to 0.67 mg kg−1, respectively. We concluded that RT practices, coupled with crop residue retention, positively affected major and micro-nutrient distribution and availability in this soil. Results highlight the importance of nutrient dynamics under different tillage and cropping systems and thus improve the nutrient recommendation in the semi-arid eco-region of Central India.

Conservation tillage supports soil macrofauna communities, infiltration, and farm profits in an irrigated maize-based cropping system of Colorado.

In the past several decades conservation tillage systems have been introduced to address the negative impacts of intensive tillage, but the potential of these technologies to improve soil function and maintain yields is still not fully understood. This study sought to examine the effects of conservation tillage on key soil quality parameters and profitability at a production scale. We evaluated soil properties and yields during the fifth and sixth years (2015 and 2016) of a field study comparing two conservation tillage systems: minimum tillage (MT) and strip tillage (ST), versus a conventional tillage control (CT). Measurements included residue cover, macrofauna abundance and diversity, permanganate oxidizable carbon (POXC), aggregate stability, and infiltration. Results from both years suggest that conservation tillage can enhance macrofauna abundance (especially earthworms) and diversity. For example, ST had higher abundance of macrofauna (486 ind. m‒2) than CT (178 ind. m‒2) in 2015, while MT had greater species richness than CT (4.12 vs. 2.00 taxa sample‐1; respectively). Infiltration rate in the ST treatment was 18% higher when compared with CT in 2015. Residue cover was positively correlated with earthworm abundance, while earthworm abundance was positively correlated with aggregated stability and infiltration. When comparing economic costs and profitability across systems, ST and MT treatments had a 34% and 22% greater net return relative to CT. These results suggest that conservation tillage has potential to improve soil quality, water dynamics, and increase farmer incomes within furrow‐irrigated systems of Colorado and beyond.

Biochemical signatures reveal positive effects of conservation tillage on arbuscular mycorrhizal fungi but not on saprotrophic fungi and bacteria

Since tillage can reduce the amount of organic C stored in soils, the use of conservation tillage practices, which exclude soil inversion, or include it less frequently, is often promoted. Soil microorganisms are closely linked to soil organic C (SOC), and they are assumed to respond quicker to management changes than SOC. Using two Swedish long-term tillage experiments, our aim was to determine whether (i) continuous conservation tillage (harrowing, H) increase microbial biomass (indicated by fatty acid signatures) compared to plowing (P), and if occasionally tilled soil (HP) was more like H or P. Also, the aim was to determine whether (ii) crop residue management has different effects on microbial biomass depending on tillage management, and whether (iii) conservation tillage and residue return increase SOC. We found that arbuscular mycorrhizal fungi (AMF) were stimulated by the H treatment compared to P treatment in the upper soil layer, and that occasional plowing resulted in intermediate amounts of AMF. The amount of microbial saprotrophs, on the other hand, was not affected by tillage treatment, and neither was the SOC concentration. Whether crop residues were returned in the autumn or not, had no direct effect on the microbial saprotrophs or the SOC after the winter, but crop residue removal stimulated AMF close to the surface in the P treatment. Although more research is needed to fully understand agricultural tillage and residue management effects on SOC dynamic, our study suggests that reducing or omitting plowing influence soil microbes, but does not necessarily result in more SOC.

Effect of Reversal of Conservation Tillage on Soil Nutrient Availability and Crop Nutrient Uptake in Soybean in the Vertisols of Central India

Effect of conservation tillage on crop performance and soil properties has been studied extensively under different agro-climatic situations. However, the impact of reversal from conservation tillage to conventional tillage on crop growth and soil nutrient release is rarely addressed. Thus, this study was conducted by converting half of the eight years old conservation tillage experiment to the conventional one with a similar level of residue return to compare the effect on soil nutrient availability and nutrient uptake in soybean crops in the Vertisols of Central India. The conservation tillage treatments included no-tillage (NT) and reduced tillage (RT) with 100% NPK (T1), 100% NPK + farmyard manure (FYM) at 1.0 Mg-carbon (C)/ha (T2), and 100% NPK + FYM at 2.0 Mg-C/ha (T3). After eight years of the experiment, the RT and NT treatments were subjected to conventional tillage, and thus the tillage treatments were RT-CT, RT, NT, and NT-CT. After tillage reversal for three growing seasons, soybean yield and nutrient uptake (N, P, K) got significantly influenced by the tillage and nutrient management. Averaged across nutrient treatments, NT showed highest soil organic carbon (SOC) content (8.4 g/kg) in the surface 0–5 cm layer. However, at 5–15 cm depth, the SOC was greater in the RT-CT treatment by 14% over RT and by 5% in the NT-CT treatment over NT. The soil nutrient availability (N and P) was not significantly (p &gt; 0.05) affected by the interaction effect of tillage and nutrient on the surface soil layer (0–5 cm). Interaction effect of tillage and nutrient was significant on available P content at 5–15 cm soil depth. In contrast to N, soil available P relatively increased with reversal of tillage in both NT and RT. Tillage reversal (NT-CT, RT-CT) and RT had significantly higher available potassium than NT in 0–5 and 5–15 cm soil layers. Among the treatments, NT-CT-T3 showed significantly higher seed N (85.49 kg/ha), P (10.05 kg/ha), and K (24.51 kg/ha) uptake in soybean. The study indicates conventional tillage with residue returns and integrated nutrient management could be a feasible alternative to overcome the limitations of no-till farming in the deep black Vertisols of Central India.

Characteristics of carbon mineralization and accumulation under long-term conservation tillage

Conservation tillage has been widely practiced to increase soil organic carbon (SOC), and reducing SOC mineralization has the potential to improve accumulation. To assess the effects of conservation tillage on characteristics of SOC mineralization and accumulation, as well as their relationship, a site experiment was established in 2008 using data from 2012 to 2019 under wheat-maize cropping system. Four treatments were investigated: no-till with straw retention (NTS, conservation tillage), no-till with straw removal (NT), conventional tillage with straw incorporation (CTS), conventional tillage with straw removal (CT). The results showed that NTS significantly improved SOC concentration than the other treatments at 0–10 cm soil depth (P < 0.05) by 5–18% in 2012 and 31–93% in 2019 (increasing increments over time). There was a negative correlation (R2 = -0.60) between SOC concentration and mineralizability. On average, the SOC mineralizability under NTS was 39.0 mg C kg−1 SOC at 0–10 cm depth, significantly lower than CTS and CT (P < 0.05). Furthermore, relative SOC mineralizability of NT/NTS, CTS/NTS, and CT/NTS was>1 and showed a linear relationship with time, indicating that NTS can increase SOC accumulation by reducing SOC mineralizability over time. A negative correlation was observed between SOC mineralizability and mean weight diameter (MWD) (R2 = -0.34), and the highest MWD under NTS, suggesting reduced mineralizability due to enhanced physical protection of soil macro-aggregates. Furthermore, the particulate organic carbon (POC) concentration was highly correlated with MWD (R2 = 0.76). Conclusively, results elucidated that higher POC under conservation tillage contributed to the macro-aggregate formation and aggregate stability at 0–10 cm depth, and thus protected SOC from mineralization, and additional SOC sequestration could be accelerated by improving the duration of conservation tillage.

Progress on the effects of conservation tillage on soil aggregates, microbes, and nematode communities

Progress on the effects of conservation tillage on soil aggregates, microbes, and nematode communities

Effect of conservation tillage and rice-based cropping systems on soil aggregation characteristics and carbon dynamics in Eastern Indo-Gangetic Plain

Traditional rice–wheat cropping system, which follows wet puddling in rice and conventional tillage in wheat, is deteriorating soil health resulting yield stagnation in the Indo-Gangetic Plains of South Asia. Conservation agriculture which endorses minimum soil disturbance, residue retention and crop diversification not only improves soil health but also reduces the CO2 concentration in atmosphere. We hypothesized that adoption of conservation agriculture could improve the soil health and soil organic carbon in comparison with conventional practices. A field experiment was conducted during 2012–2015 to observe the effects of different tillage practices and cropping systems on soil aggregation and carbon dynamics. The experiment comprised of three cropping systems, viz. rice–wheat, RW; rice–maize, RM; rice–lentil, RL, practiced in three tillage practices, viz. conventional tillage, CT; reduced tillage, RT; reduced tillage with 30% residue, RT30 in factorial randomized block design. Adoption of RT and RT30 resulted in higher macroaggregate content of 51.7 and 61.2%, respectively, in comparison with CT. Total water stable aggregates and mean weight diameter (MWD) of aggregates were considerably higher in RT and RT30 treatments, and the effect was most pronounced in the upper 0–15 cm soil layer. The rice–maize cropping system registered the highest macroaggregate content, water stable aggregates (WSA) and MWD of 55.6%, 80.0% and 2.28 mm, respectively, in the upper surface soil. The rice–maize cropping systems under RT30 recorded the highest total soil organic carbon (SOC) stock (51.0 Mg ha−1) in comparison with other systems after 3 years of experimentation. Reduced tillage and residue management resulted in positive changes in soil infiltration rate. The effect of tillage operations and cropping systems on different soil properties (aggregate distribution, WSA, MWD and geometric mean diameter of aggregates, SOC stock, Bulk density) was mostly limited to surface layer of soil.

Evaluation of conservation tillage practices for enhancing productivity of sunflower (Helianthus annuus L.) under rice fallow environment of Odisha

Field experiment was conducted to assess the effect of conservation tillage (reduced, minimum and zero tillage) and conventional tillage with three hybrids (DRSH-1, KBSH-44, MSFH-17) and three fertility levels (50% RDF,100% RDF and 150% RDF) on productivity of sunflower. Zero tillage recorded highest growth parameters, yield attributing characters and seed yield (1.91 t/ha), stover yield (4.36 t/ha) and oil yield (0.73 t/ha). Crop grown under zero tillage conditions was taller (165.7 cm), had more number of leaves/plant (30.3) and accumulated more dry matter (565 g/m2). Among the hybrids, KBSH-44 recorded the highest seed yield (1.81 t/ha), stover yield (4.22 t/ha)and oil yield (0.70 t/ha). Sunflower fertilized with 150% RDF recorded significantly highest seed yield (2.09 t/ha), stover yield (5.0 t/ha) and oil yield (0.81 t/ha) as well as the highest values of yield attributing characters which were promoted by the better growth attributing characters. Sunflower hybrids under zero tillage fertilized with 150% RDF (90:120:90 kg N: P2O5: K2O/ha) found most remunerative under rice fallow environment.

Effects of Conservation Tillage on Soil Physicochemical Properties and Crop Yield in an Arid Loess Plateau, China

Conservation tillage can improve soil physical structure and water storage, protect moisture, and increase crop yield. However, the long-term adoption of a single tillage method may have some adverse effects on soil and ecological environment, although crop yields have increased. Through informed allocation of soil tillage techniques, the combination and configuration of soil tillage measures, such as rotary tillage, subsoiling, and no tillage may reduce the shortcomings of traditional long-term farming. To explore the long-term production mode suitable for production of maize in the loess dryland area, a long-term experiment was conducted in Fuping County, Shaanxi Province, from 2013 to 2018. Six farming modes were used in the experiment: no tillage/subsoiling (N ↔ S), subsoiling/rotary tillage (S ↔ R), rotary tillage/no tillage (R ↔ N), continuous no tillage (N ↔ N), continuous subsoiling (S ↔ S), and continuous rotary tillage (R ↔ R). The changes in soil physical and chemical properties, soil water use patterns, soil water storage, conservation effects during the fallow and growth period, and the effects on farmland yield increase were analyzed. The results showed that rotary tillage can effectively improved soil structure and reduced soil bulk density, where N ↔ S treatment soil bulk density is low and in 0–60 cm soil layer averaged 1.31 g/cm3. Different tillage treatments could be used during the fallow period to store additional soil moisture: the N ↔ S treatment showed good water storage effect. Compared to traditional tillage, different tillage methods provided better soil moisture conditions for crops during the growth period, where N ↔ S treatment showed good soil moisture status during the growth period of spring maize. Among all the treatments, N ↔ S treatment effectively increased the organic carbon storage in the 0–60 cm soil layer, which was 54.3 t/hm2. Compared with traditional tillage, different tillage treatments effectively increased plant height and dry matter accumulation of spring maize, where N ↔ S treatment was found to be the best. Compared with the traditional rotary tillage model, the N ↔ S treatment significantly increased crop yield and water use efficiency (WUE) in continuous cropping fields of corn, the average yield of spring corn was 9340.2 kg/hm2, and the average WUE was 22.9 kg/(hm2·mm). In summary, for long-term sustainable development, the N ↔ S model is the best rotational tillage mode for continuous maize cropping in loess soil.

Conservation tillage and weed management practices effect on weeds, yield and profitability of cowpea (Vigna unguiculata)

An experiment was conducted from 2014-2018 to find out the effect of conservation tillage and weed management methods on weed flora, growth and yield of cowpea (Vigna unguiculata (L.) Walp. cv. RC 101) under pearlmilletmustard- cowpea cropping system. The results showed that amongst tillage treatments, zero tillage with residue application during both kharif and rabi season and only during rabi for four years significantly increased the the grain yield by 49 and 18%, gross returns by 43 and 14% and reduced the total weed biomass by 48 and 32%, respectively with higher weed control efficiency compared to zero tillage without residue application. Among different weed flora, zero tillage with residue application during both kharif and rabi season and only during rabi reduced the narrow-leaved weeds population by 40 and 19%, broad-leaved weeds by 23 and 8%, respectively. All the tillage conditions had not significantly controlled sedges. On the other hand, among different weed management practices, the pre-emergence application of pendimethalin + imazethapyr 1.0 kg/ha with one hand weeding at 20-25 DAS resulted in the significant reduction of total weed biomass, highest grain yield, weed control efficiency and gross returns. The integrated weed management approach reduced the narrow-leaved weeds by 49%, broad-leaved weeds by 52% and sedges by 59% compared to herbicides application alone. However, the interaction effect of tillage practices and weed management approach was not significant except for the total weed biomass at harvest.

Global meta-analyses show that conservation tillage practices promote soil fungal and bacterial biomass

Despite a large number of published studies, a consensus has not been reached on how soil fungal and bacterial biomass, the primary regulators for soil organic matter decomposition, respond to conservation tillage, i.e., no or reduced tillage with >30 % residue covers. In this study we conducted a global meta-analysis of 60 studies to investigate the effects of conservation versus conventional tillage on soil fungal and bacterial biomass, fungal-to-bacterial ratios, and their relationship to other soil properties. Our results showed that conservation tillage greatly increased overall soil microbial biomass (37 %), including both fungal (31 %) and bacterial biomass (11 %), especially in top 20-cm soils or no-till agro-ecosystems, but conservation tillage effects were non-significant in sandy soils. Regardless of soil depth and tillage intensity, fungal-to-bacterial ratios did not greatly increase in conservation tillage scenarios, but were significantly affected by soil texture. Conservation tillage was also associated with significant increases in soil total C and N, and reduced soil pH. Increases in soil total C were positively associated with both fungal and bacterial biomass increases. Years under conservation tillage, time between last convention tillage to soil sampling, may indirectly affect fungal and bacterial biomass through soil C accumulation. Our meta-analysis demonstrates that soil fungi and bacteria both respond positively to conservation tillage and are significantly associated with soil C content increase.

Soil organic carbon increment sources and crop yields under long‐term conservation tillage practices in wheat‐maize systems

AbstractLong‐term tillage and straw incorporation significantly affect soil organic carbon (SOC) sequestration and crop yield. However, the studies on the SOC sources under multicropping system are relatively few. The objective of this study was to evaluate the effects of conservation tillage on SOC and crop yields and distinguish the SOC sources from wheat (C3) and maize (C4). Therefore, the dynamics of SOC, SOC sequestration, and crop yield were evaluated during 15 years of conservation agriculture under conventional tillage (CT), subsoiling (ST), rotary tillage (RT), and zero tillage (ZT) without or with straw incorporation (CTS, STS, RTS, and ZTS, respectively). The results indicated that the highest mean SOC concentration in the 0‐ to 30‐cm soil was found under STS (11.80 g kg−1), which increased by 2.29 g kg−1 than that under CT, whereas RT had the lowest mean SOC concentration (8.10 g kg−1). The increases in annual yield ranged from 0.58 (ZT) to 4.93 (ST) Mg ha−1 during 2005–2017. In comparison with the annual yield of CT, that of STS increased by 2 Mg ha−1 and was significantly higher than other treatments (p &lt; .05) except ZTS and CTS. In comparison with CT, the SOC stock and carbon sequestration rate of STS were the highest and increased by 15.64 Mg ha−1 and 1.05 Mg ha−1 yr−1, respectively, in the 0‐ to 30‐cm soil. Moreover, the relative contribution of wheat residues to SOC was higher than maize residues under all treatments. Thus, subsoiling combined with C3 straw incorporation was more suitable for restoring degraded land and increasing yields.

Conservation tillage effects in the Atlantic Coastal Plain: An APEX examination

The Conservation Effects Assessment Project (CEAP) was established to develop a scientific understanding and methodology for estimating environmental benefits and effects of conservation practices on agricultural landscapes at watershed, regional, and national scales. CEAP9s goal is to improve the effectiveness of conservation practices and programs by quantifying conservation effects and providing the science and education needed to enrich conservation planning, implementation, management decisions, and policy. Field observations and computer-based simulation of the effects of agricultural conservation are important components of CEAP. This research supports the CEAP effort by utilizing well-documented field data in conjunction with the Agricultural Policy/Environmental eXtender (APEX) model to quantify long-term conservation effects. In this study, field data collected at a research site located near Tifton, Georgia, were used to evaluate APEX and to quantify long-term benefits of implementing conservation tillage in the Atlantic Coastal Plain region of the United States. The objectives of this research were to (1) quantify differences in crop yield, hydrology, and sediment transport for conventional and conservation tillage systems in the Atlantic Coastal Plain; (2) develop a calibrated APEX simulation for these tillage systems; and (3) quantify the performance of the APEX model with respect to crop yields, hydrology, and sediment yield. Fourteen years of crop yield, surface runoff, subsurface flow, and sediment transport data were quantified comparing conventional tillage (CT) to strip tillage (ST). No treatment differences were found for either cotton (<i>Gossypium hirsutum</i> L.) or peanut (<i>Arachis hypogea</i> L.) yields. Surface runoff from the CT was found to be 1.7 times that of the ST, while subsurface flow from the ST was found to be 1.7 times that of CT. Total water loss (surface and subsurface) was nearly equivalent for the two systems: 30% of annual rainfall. Satisfactory model performance was found for APEX surface runoff simulations. Mixed results were found for model performance of crop yield while model simulations of subsurface flow and sediment yield were less than satisfactory. The APEX modeling framework provides a useful tool for assessing crop yield and hydrologic differences between tillage management systems in the Atlantic Coastal Plain. Additional refinement of modeling approaches may be necessary to adequately represent subsurface flow and sediment transport in these same systems.

Морфогенез чорнозему типового та ізогумусолю за довготривалого використання різних систем обробітку грунту

Chernozems involvement in agriculture influence some natural transformation processes in the soil profile leading to corresponding changes in the morphological features of genetic horizons and their properties. The aim of our research was to identify the morphological changes of typical chernozem and isohumusol under the long-term tillage influence. In the article were compared similar Mollisols, which were formed due to chernozemic process, Forest-Steppe region and loess, but under influence of different facial conditions. The study was conducted at a research station in Velyka Snitynka village, Fastiv district of Kyiv region (50°5′N, 30°2′E) and at the National Agroecosystem Research Station in Hailun, China (47°126′N, 126°38′E). There was used comparative geographical, morphological and statistical research methods during studying. Our findings have defined, that H and H + Hp horizons were deeper by 0.7-5.8 and 9.8-22.4 cm at isohumusol, H + Hp + Phk + P (h) k horizons - by 27.3-53,1 cm - at typical chernozem due to additional 38.4-42.3 cm horizon made of mole influenced loess enriched with humus incrustations. The upper H horizon was the deepest under plowing: 54.3 – at typical chernozem and 55.0 cm – at isohumusol and shortened under minimum till - 48.2 cm – at typical chernozem. Humus horizons had more brown colors: 10YR 3/2, 10YR5/2 - 10YR5/3 - at isohumusol and gray colors: 2,5Y 3/1 - 2,5Y 5/3, 10YR 4/2 - 10YR 5/2 - at typical chernozem. Conservation tillage effects on closer, to the soil surface, humus horizons placement, better aggregation of granular peds, the profile has higher amount of up and down oriented pores between aggregates, carbonates boil in the lower part of the upper transition horizon. Chernozem profile acquires some characteristics of their virgin analogues under conservation technologies use.

Effective alleviation of rural poverty depends on the interplay between productivity, nutrients, water and soil quality

Most of the world's poorest people come from rural areas and depend on their local ecosystems for food production. Recent research has highlighted the importance of self-reinforcing dynamics between low soil quality and persistent poverty but little is known on how they affect poverty alleviation. We investigate how the intertwined dynamics of household assets, nutrients (especially phosphorus), water and soil quality influence food production and determine the conditions for escape from poverty for the rural poor. We have developed a suite of dynamic, multidimensional poverty trap models of households that combine economic aspects of growth with ecological dynamics of soil quality, water and nutrient flows to analyze the effectiveness of common poverty alleviation strategies such as intensification through agrochemical inputs, diversification of energy sources and conservation tillage. Our results show that (i) agrochemical inputs can reinforce poverty by degrading soil quality, (ii) diversification of household energy sources can create possibilities for effective application of other strategies, and (iii) sequencing of interventions can improve effectiveness of conservation tillage. Our model-based approach demonstrates the interdependence of economic and ecological dynamics which preclude blanket solution for poverty alleviation. Stylized models as developed here can be used for testing effectiveness of different strategies given biophysical and economic settings in the target region.

Interactive effects of conservation tillage, residue management, and nitrogen fertilizer application on soil properties under maize-cotton rotation system on highly weathered soils of West Africa

Loss of topsoil, enriched with nutrients, reduces soil fertility, and is one of the major impediments to sustainable crop production in West Africa. Appropriate management practices can lead to a stable restoration of land’s capacity to provide adequate ecosystem services. Thus, our study aimed to investigate the impact of alternative management practices and their interactions on topsoil (0–20 cm) organic carbon (SOCd), nutrient stocks [total nitrogen (STNd), phosphorus (SPd) and potassium (SKd)] under a maize-cotton rotation system on highly weathered soils of West Africa. To this end, on-farm trials were set up on four sites in the sub-humid Savanna of West Africa (2 in Benin (St1 and St2), and 2 in Burkina-Faso (St3 and St4)) in a strip-split plot layout, where 2 levels of tillage (contour ridge tillage, Ct and reduced tillage, Rt) were considered as main plot factor, and sub-plot factors included 2 levels of crop residue management (removed, CRr and incorporated, CRi), and 2 levels of N fertilizer (control, N0 and recommended rate, Nr). In 2016, after 5 cycles of annual maize-cotton rotation (2012–2016), the largest pool of soil nutrients was recorded on St3 (Haplic Lixisol, footslope in Benin), while the lowest content was observed on St1 (Ferric Lixisol, footslope in Burkina). When comparing the treatments, we found that Ct combined with CRi improved soil nutrient stocks in upslope sites, St2 (Eutric Plinthosol, upslope in Burkina) and St4 (Plinthic Lixisol, upslope in Benin), which are more prone to erosion. At the same time, footslope sites (St1 and St3) benefited from Rt coupled with CRi. CRi promoted an increase in SPd and SKd on all sites except St1 (Haplic Lixisol on footslope). The application of recommended dose of N fertilizer improved STNd under the Ct system in upslope regions and under the Rt system in footslope regions. However, no significant difference was observed for soil pH among the treatments across all sites. In summary, the efficiency of practices for conservation of soil nutrient stocks was closely related to landscape position of the field, which was correlated with soil moisture, textural class, and gravel content. Consequently, site-adapted tillage practices combined with residue incorporation are crucial for sustainable soil fertility management and crop productivity under maize-cotton rotation in smallholder production systems in West Africa.