Outcomes of Long-Term Conservation Tillage Research in Northern China

Sustainable food production has long been a priority for mankind and this is being challenged by limited arable land, challenged landscapes, and higher human population growth. China started conservation farming around the 1950’s. However, main Conservation Tillage (CT) research started in 1992. Using a systematic meta-analysis approach, this review aims at examining China’s approach to CT and to characterize the main outcomes of long-term CT research across northern China. Data from organizations in charge of CT research in China showed an improvement in crop yield of at least 4% under double cropping systems and 6% under single cropping systems in dry areas of northern China. Furthermore, long-term CT practices were reported to have improved soil physical properties (soil structure, bulk density, pore size, and aggregate stability), soil nutrient levels, and reduction in greenhouse gas emission. Other benefits include significant increase in income levels and protection of the environment. Limitations to CT practice highlighted in this study include occasional reduction in crop yields during initial years of cropping, significant reduction in total N of soils, increase in N2O emission, and the need for customized machinery for its implementation. Outcomes of CT practice are ecologically and economically beneficial though its limitations are worth cogitating.

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Effects of 15 years of conservation tillage on soil structure and productivity of wheat cultivation in northern China

Soil Research ◽

10.1071/sr07003 ◽

2007 ◽

Vol 45 (5) ◽

pp. 344 ◽

Cited By ~ 95

Author(s):

Hongwen Li ◽

Huanwen Gao ◽

Hongdan Wu ◽

Wenying Li ◽

Xiaoyan Wang ◽

...

Keyword(s):

Soil Structure ◽

Conservation Tillage ◽

Northern China ◽

Farming System ◽

Triticum Aestivum L ◽

Conventional Tillage ◽

Long Term Effects ◽

Total N ◽

Dryland Farming

An understanding of long-term tillage and straw management impact on soil structure and productivity is necessary for the further development of conservation tillage practice in dryland farming areas. Data from a 15-year field experiment conducted in Shanxi, on the loess plateau of northern China, were used to compare the long-term effects of no-till and residue cover (NTSC) with conventional tillage (CT) in a winter wheat (Triticum aestivum L.) monoculture. Long-term CT and straw removal resulted in poor soil structure and low productivity. Mean soil bulk density in NTSC was 1.5% less than in CT and capillary porosity (<60 μm) 3.2% greater. Water stability of macro-aggregates >2 mm was much greater for NTSC in the 0–0.20 m profile. Soil organic matter and total N and P were 27.9%, 25.6%, and 4.4% greater in NTSC, respectively, and earthworms (19/m2) were found only in the no tillage treatment. Crop yield and water use efficiency tended to be higher under NTSC than under CT, especially in the years of low rainfall, suggesting that the change in soil structure has provided a better environment for crop development. Our 15-year experimental data indicate that NTSC is a more sustainable farming system, which can improve soil structure, and increase productivity with positive environmental impacts in the rainfed dryland farming areas of northern China.

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Replacing Synthetic Nitrogen Fertilizer with Different Types of Organic Materials Improves Grain Yield in China: A Meta-Analysis

Agronomy ◽

10.3390/agronomy11122429 ◽

2021 ◽

Vol 11 (12) ◽

pp. 2429

Author(s):

Xiaoru Fan ◽

Zekai Chen ◽

Zihan Niu ◽

Ruiyao Zeng ◽

Jingmin Ou ◽

...

Keyword(s):

Grain Yield ◽

Nitrogen Fertilizer ◽

Organic Materials ◽

Crop Yields ◽

Meta Analysis ◽

Chicken Manure ◽

Agricultural Practice ◽

Different Types ◽

Synthetic Nitrogen Fertilizer

Synthetic nitrogen fertilizer substitution (NSS) with different types of organic material is a cleaner agricultural practice for reducing the application of synthetic N input in farmlands while also relieving the environmental issues caused by the discharge of organic wastes. However, the effects of the NSS practice on crop yields, being the primary objective of agricultural activity, is still uncertain in China. This study conducted a meta-analysis to assess the impacts of the NSS practices with different types of organic materials on crop yields. Results showed that the average crop yield was increased by 3.4%, with significant differences under NSS, thereby demonstrating that this practice contributed to improving crop yields, especially of rice and maize. According to published reports, the NSS practices involving chicken manure, pig manure, and crop straw increased crop yields by 4.79, 7.68, and 3.28%, respectively, with significant differences, thus demonstrating the superior effects needed for replacing synthetic N fertilizer. Moreover, substitution ratios (SR) between 0% and 60% could be suggested when using the NSS practice, with the high SR recommended when the original soil fertility was adequate for crops. Considering the long-term effects of applied organic materials, improving the grain yield with the NSS practice should be expected in the long-term. By effectively applying the NSS, this study attempted to scientifically decide on the type of organic materials and the appropriate SR based on the conditions of the soil and the crop. The results provide research information for the development of clean agricultural production and food security in China.

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Enhancing Soil Water Content for Increased Food Production in Semi-Arid Areas of Kenya Results From an On-Farm Trial in Mwala District, Kenya

Journal of Agricultural Science ◽

10.5539/jas.v6n4p125 ◽

2014 ◽

Vol 6 (4) ◽

pp. 125 ◽

Cited By ~ 3

Author(s):

Anne Karuma ◽

Peter Mtakwa ◽

Nyambilila Amuri ◽

Charles K. Gachene ◽

Patrick Gicheru

Keyword(s):

Soil Moisture ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Water Conservation ◽

Crop Yields ◽

Conservation Tillage ◽

Cropping Systems ◽

Soil Conditions ◽

Tillage Methods

Soil water conservation through tillage is one of the appropriate ways of addressing soil moisture deficit in rainfed agriculture. This study evaluated the effects of tillage practices on soil moisture conservation and crop yields in Mwala District, Eastern Kenya during the long rains (LR) and short rains (SR) of 2012/13. Six tillage systems: Disc plough (MB), Disc plough and harrowing (MBH), Ox-ploughing (OX), Subsoiling – ripping (SR), Hand hoe and Tied Ridges (HTR) and Hand hoe only (H) and, three cropping systems namely, sole maize, sole bean and maize - bean intercrop, were investigated in a split-plot design with four replicates. Data on soil water content was monitored at different weeks after planting and the crop yields at end of each growing season. A three-season average shows that soil water content and crop yields were higher in conventional tillage methods compared to the conservation tillage methods. Long term tillage experiments are thus required at different locations, under various environmental and soil conditions to validate the study findings.

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Tillage Intensity Effects on Soil Structure Indicators—A US Meta-Analysis

Sustainability ◽

10.3390/su12052071 ◽

2020 ◽

Vol 12 (5) ◽

pp. 2071 ◽

Cited By ~ 6

Author(s):

Márcio R. Nunes ◽

Douglas L. Karlen ◽

Thomas B. Moorman

Keyword(s):

Crop Production ◽

Soil Structure ◽

Management Practices ◽

Cropping Systems ◽

Meta Analysis ◽

Soil Health ◽

Health Assessment ◽

Aggregate Stability ◽

Soil Penetration Resistance ◽

Wet Aggregate Stability

Tillage intensity affects soil structure in many ways but the magnitude and type (+/−) of change depends on site-specific (e.g., soil type) and experimental details (crop rotation, study length, sampling depth, etc.). This meta-analysis examines published effects of chisel plowing (CP), no-tillage (NT) and perennial cropping systems (PER) relative to moldboard plowing (MP) on three soil structure indicators: wet aggregate stability (AS), bulk density (BD) and soil penetration resistance (PR). The data represents four depth increments (from 0 to >40-cm) in 295 studies from throughout the continental U.S. Overall, converting from MP to CP did not affect those soil structure indicators but reducing tillage intensity from MP to NT increased AS in the surface (<15-cm) and slightly decreased BD and PR below 25-cm. The largest positive effect of NT on AS was observed within Inceptisols and Entisols after a minimum of three years. Compared to MP, NT had a minimal effect on soil compaction indicators (BD and PR) but as expected, converting from MP to PER systems improved soil structure at all soil depths (0 to >40-cm). Among those three soil structure indicators, AS was the most sensitive to management practices; thus, it should be used as a physical indicator for overall soil health assessment. In addition, based on this national meta-analysis, we conclude that reducing tillage intensity improves soil structure, thus offering producers assurance those practices are feasible for crop production and that they will also help sustain soil resources.

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Alley Cropping Increases Land Use Efficiency and Economic Profitability Across the Combination Cultivation Period

Agronomy ◽

10.3390/agronomy9010034 ◽

2019 ◽

Vol 9 (1) ◽

pp. 34 ◽

Cited By ~ 3

Author(s):

Huasen Xu ◽

Huaxing Bi ◽

Lubo Gao ◽

Lei Yun

Keyword(s):

Land Use ◽

Crop Yields ◽

Alley Cropping ◽

Cropping Systems ◽

Land Use Efficiency ◽

Term Experiment ◽

Long Term Experiment ◽

Use Efficiency ◽

Short Term Experiment

Alley cropping allows the famer to effectively use available resources and yield more benefits. Choosing suitable associated crop and mitigating the competition between trees and crops are crucial for designing the alley cropping systems. We conducted a long-term experiment, including apple (Malus pumila)/peanut (Arachis hypogaea), apple/millet (Setaria italica) and apple/maize (Zea mays) alley cropping systems with conventional intercropping distance, and corresponding monocultures (Exp.1), and a short-term experiment with improved intercropping distance in the same three combinations (Exp.2) in the Loess Plateau, China. The results showed crop yields in three alley cropping systems were lower than the corresponding monocultures. Apple yields were significantly constrained by millet and maize in the alley cropping systems, but not sensitive to the presence of peanut. Land equivalent ratios (LERs) ranged from 0.44 to 0.89 before the tree bore fruit. The LERs were greater than 1.0 after the tree bore fruit, and the apple trees made a decisive contribution to the land use advantage. Net present values of three alley cropping systems were on average 60.1% higher than the corresponding monocultures across the alley cropping period. The maximum annual present value in the first–fifth, sixth and seventh–ninth years after the alley cropping establishment was observed in the apple/maize, apple/millet and apple/peanut system, respectively. These results highlight that choosing the optimal alley cropping management and suitable associated crops at different years after establishment may allow farmers to increase the land use efficiency and economic profitability.

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Economics of reduced tillage fallow-crop systems in the Dark Brown soil zone of Alberta

Canadian Journal of Soil Science ◽

10.4141/cjss96-049 ◽

1996 ◽

Vol 76 (3) ◽

pp. 411-416 ◽

Cited By ~ 16

Author(s):

E. G. Smith ◽

R. E. Blackshaw ◽

C. W. Lindwall ◽

F. J. Larney ◽

T. L. Peters

Keyword(s):

Conservation Tillage ◽

Cropping Systems ◽

Economic Benefits ◽

Research Centre ◽

Reduced Tillage ◽

Term Study ◽

Net Returns ◽

Long Term Study ◽

Tillage Methods

The use of conservation tillage management in fallow cropping systems reduces soil erosion and improves soil quality. The economic benefits of these alternate tillage methods are less certain. This study examined the economic returns from reduced tillage methods on fallow using yield and input data from two experiments at the Agriculture and Agri-Food Canada Research Centre at Lethbridge, Alberta. One experiment was long-term study initiated in 1955 with eight treatments, the second was a 5-yr study with 15 treatments. Results from the 5-yr study indicated no difference in net returns between conventional and reduced tillage fallow systems. In contras, the long-term study net returns were highest for tilled systems and lowest for herbicide-only systems. The long-term study had a build-up of weeds that are difficult to control with herbicides alone. The resulting lower average yield and higher herbicide costs of the herbicide-only treatments in the long-term study accounted for most of the contrasting results between the two experiments. An economic evaluation of tillage practices requires the entire system to be evaluated, not just the tillage component. Key words: Economics, tillage, reduced tillage, conservation practices, weed control

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Soil organic carbon dynamics under long-term fertilizations in arable land of northern China

Biogeosciences Discussions ◽

10.5194/bgd-6-6539-2009 ◽

2009 ◽

Vol 6 (4) ◽

pp. 6539-6577 ◽

Cited By ~ 8

Author(s):

W. J. Zhang ◽

X. J. Wang ◽

M. G. Xu ◽

S. M. Huang ◽

H. Liu ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Cropping Systems ◽

Inorganic Nitrogen ◽

Northern China ◽

Double Cropping ◽

Conversion Rates ◽

Warm Temperate ◽

Nitrogen Phosphorus

Abstract. Soil organic carbon (SOC) data were collected from six long-term experiment sites in the upland of northern China. Various fertilization (e.g. inorganic fertilizations and combined inorganic-manure applications) and cropping (e.g. mono- and double-cropping) practices have been applied at these sites. Our analyses indicate that long-term applications of inorganic nitrogen-phosphorus (NP) and nitrogen-phosphorus-potassium (NPK) result in a significant increase in SOC at the sites with the double-cropping systems. The applications of inorganic NP and/or NPK combined with manure lead to a significantly increasing trend in SOC content at all the sites. However, the application of NPK with crop residue incorporation can only increase SOC content in the warm-temperate areas with the double-cropping systems. Regression analyses suggest that soil carbon sequestration responds linearly to carbon input at all the sites. Conversion rates of carbon input to SOC decrease significantly with an increase of annual accumulative temperature or precipitation, showing lower rates (6.8%–7.7%) in the warm-temperate areas than in the mid-temperate areas (15.8%–31.0%).

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

Land Degradation and Development ◽

10.1002/ldr.3531 ◽

2020 ◽

Vol 31 (9) ◽

pp. 1138-1150 ◽

Cited By ~ 1

Author(s):

Zhen Liu ◽

Tianping Gao ◽

Shenzhong Tian ◽

Hengyu Hu ◽

Geng Li ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Crop Yields ◽

Conservation Tillage ◽

Tillage Practices

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The Elusive General Factor of Personality: The Acquaintance Effect

European Journal of Personality ◽

10.1002/per.1933 ◽

2013 ◽

Vol 27 (5) ◽

pp. 507-520 ◽

Cited By ~ 17

Author(s):

Timo Gnambs

Keyword(s):

Meta Analysis ◽

General Factor ◽

Short Term ◽

Personality Psychology ◽

Total N ◽

Weak Support ◽

General Factor Of Personality ◽

Normative Ratings ◽

Average Individual

A general factor (gp) at the apex of personality has been suggested to account for the correlations between the Big Five. Although the gp has received ample support from monomethod studies, results from studies incorporating different methods have remained rather ambiguous; some have identified a gp across different informants, whereas others have not. It was hypothesized that these divergent findings are a result of varying lengths of acquaintance between raters. To this end, the current study presents a multitrait multi–informant meta–analysis (total N = 11 941) that found weak support for a gp as a substantive trait of personality. Evidence for a gp was susceptible to the length of acquaintance between informants. Although a gp could be identified for short–term acquaintances, it remained elusive at long–term acquaintance. Thus, the gp in other ratings more likely reflects normative ratings of an average individual rather than ratings of the specific target person. Copyright © 2013 European Association of Personality Psychology

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Response and adaptation of soybean systems to climate warming in Northeast China: insights gained from long-term field trials

Crop and Pasture Science ◽

10.1071/cp11167 ◽

2011 ◽

Vol 62 (10) ◽

pp. 876 ◽

Cited By ~ 3

Author(s):

H. F. Zheng ◽

L. D. Chen ◽

X. Z. Han

Keyword(s):

Global Warming ◽

Climate Warming ◽

Crop Yields ◽

Cropping Systems ◽

Soybean Seed ◽

Growing Season ◽

Yield Reduction ◽

Seed Filling ◽

Term Field

Developing and assessing successful strategies to alleviate adverse impact of climate warming presents a new opportunity for sustainable agriculture and adaptation investment. Efforts to anticipate adaptation of cropping systems may benefit from understanding the global warming effects within decades. This study quantitatively examines the temperature warming impacts during, respectively, growing season and seed filling on soybean yields by using data from long-term field fertilisation experiments from 1987 to 2004. Here we report that grain yields significantly decreased with rising temperature during growing season, whereas the effects of increasing temperature at seed-filling stage on crop yields were significantly positive. The results indicate that a further temperature increment during seed filling appears to decrease soybean system’s risk of yield reduction. Importantly, we inferred that earlier occurrence of seed filling would increase the temperature of this period. The implication is that advancing the onset of soybean seed filling could be an effective adaptation option to global warming, providing an average yield benefit of ~14% per 10 days before the present date.

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