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931.
C. Royo    A. Rodriguez  I. Romagosa 《Plant Breeding》1993,111(2):113-119
Adaptation of seven complete and twelve substituted triticales to specific soil types has been studied, based on a series of twenty trials carried out in 1989 and 1990 across Spain. The nature of the GE interaction for grain yield was revealed by means of the additive main effects multiplicative interaction (AMMI) model and using the soil pH at the different sites as linear covariate. The percentage of the variability explained by the first principal component axis of the AMMI model was 72 and 65 % for the two years, suggesting a specific pattern of adaptation. Soil pH was the single most important environmental factor to explain the adaptation of complete and substituted types. Complete triticales outyielded substituted genotypes in the majority of sites. Triticale adaptation to acid and alkaline soils seems to be largely controlled by the single wheat/rye chromosome 2D(2R) substitution, for which both types differ. Complete triticales seem better adapted to the acid soils, whereas substituted types are, in general, more suited to alkaline soils.  相似文献   
932.
    
The ravine is often regarded as the worst instance of how water erosion is causing land deterioration. The farmers' livelihoods are often threatened by the ravine's expansion into the surrounding 50 m buffer zone, leaving them with no choice except to work as landless workers. Due to the high expense of ravine restoration, it is not economically possible to begin the process of reclamation in all of the ravine lands at once. As a result, it is necessary to recognize the prospective regions to bring in reclamation activities. In this work, the ravine vulnerability index for the Mahi ravine in Western India was developed using a cutting-edge hybrid methodology. For the development of the ravine vulnerability index, it was determined that the sand, silt, clay, organic carbon, soil erodibility factor, slope, stream power index, topographic wetness index, sediment transport index, and cover factor were crucial components. Weights were applied to various parameters based on the perceived significance of each parameter in relation to another in the decision matrix of the analytical hierarchical process. The number of iterations made to reach a consistency ratio of under 10% to determine the final priority weights for each parameter. The sediment transport index had the lowest priority weight (1.4), whereas the sand had the highest priority weight (28.5). For reclamation purposes, the prospective active zones inside the designated ravine's 50-m buffer zone, which covered an area of 63,031 acres, were determined. According to the ground truth-validated ravine vulnerability index, possible reclamation zones were found in the 16,703 ha (26.50%) region of Mahi ravine, which was given extremely high priority. As per the Mahi ravine's land capacity classification, 20,275 ha (32.16%) of it is arable land, and 18,687 ha (29.65%) of it is non-arable land that is ideal for soil and water conservation treatments.  相似文献   
933.
    
In many parts of the world, former agricultural sites have been abandoned particularly when productivity is marginal or policies are implemented to develop ecosystem recovery. Understanding the recovery trajectory of soil, plants, and microbes is critical for developing restoration plans and the most effective policies. Here, we evaluated the changes in soil properties, plants, and the bacterial community along a chronosequence of agricultural abandonment (5, 15, and 20 years) in two different types of steppes (desert and typical steppes), respectively, in Inner Mongolia, China. Active farmland and natural grassland were selected as reference sites. In both study sites, soil water content and soil organic carbon content increased, while bulk density and nitrogen decreased across the chronosequence, all becoming comparable to that of natural grassland. Plant diversity, above- and below-ground biomass increased, while perennial graminoids and forbs replaced annuals as the dominant functional groups with the elongation of abandonment. Bacterial diversity increased along the chronosequence in the drier desert steppe, but not in the wetter typical steppe. Over the chronosequence, Acidobacteria, a phyla tending to live in lower carbon conditions, were replaced by Proteobacteria and Actinobacteria, which favor abundant carbon environments. Redundancy analysis shows that soil organic carbon, below-ground plant biomass, and nitrate were the main factors that driving bacterial community composition. Our results demonstrated that spontaneous recovery without any human disturbance was an effective way for the restoration of arid and semi-arid grassland ecosystems in Inner Mongolia, and emphasized the importance of soil and plant restoration for the recovery of bacterial community.  相似文献   
934.
    
Soils derived from loess are fertile but susceptible to accelerated degradation in response to agricultural practices. The objective of our study was to evaluate the long-term effects of alfalfa (Medicago sativa L.) integrated with contrasting organic amendments (29 years) to rejuvenate degraded loess via total soil organic carbon (SOC) sequestration. The replicated study was conducted in concrete lysimeter plots (2 m long × 1 m wide × 60 cm deep) filled with degraded loess materials followed by planting of alfalfa with cattle manure (60 Mg/ha) or vermicompost (27 Mg/ha) amendments. After 29 years, SOC concentration increased by 5.3–6.2-fold under alfalfa–organic amendments compared to the control. A similar impact of alfalfa–organic amendments was observed on the humic acid, fulvic acid, and humin concentrations. There was an overestimation of SOC stocks (151 ± 48 kg/ha) when equivalent depth was used compared to equivalent mass of soil. While the SOC sequestration rates were 614 ± 129, 710 ± 69, and 744 ± 161 kg/ha/year at 0–10 cm depth under alfalfa, alfalfa–manure, and alfalfa–vermicompost treatments, respectively, the SOC sequestration rates decreased with depth. Significantly higher values of carbon pool index (CPI) and carbon management index (CMI) under alfalfa–organic amendments justified our results associated with the SOC sequestration; however, the SOC lability (CL) decreased under alfalfa–organic amendments, when compared to the control. A significant nonlinear inverse relationship (R2 = 0.80) between the CPI and CL suggested that SOC sequestration is significantly dependent on its lability or vice versa. Our results suggested that the impact of alfalfa–organic amendments significantly rejuvenated the degraded loess soils via SOC sequestration.  相似文献   
935.
    
The North China Plain plays an important role in China's crop cultivation regions, with the wheat-maize rotation serving as the predominant cropping system. Nonetheless, a dearth of research refers to the impact of tillage and fertilizer employment on soil quality (SQ) in this region. In this study, the primary objective centered on utilizing the soil quality index (SQI) derived from both minimum and total datasets (MDS, TDS) by the linear and nonlinear scoring criteria to assess SQ. The results indicated that there was a significant correlation between wheat-maize yield and SQI, revealing a significant association between yield and key soil parameters such as bulk density, soil porosity, total phosphorus, alkali-hydrolyzed nitrogen, available phosphorus and cation exchange capacity at 0–60 cm soil layer. The study identifies that substantially elevated SQI mean values were completely under T8 whose values were 0.980 (linear), 0.672 (nonlinear) under MDS and 0.908 (linear), 0.701 (nonlinear) under TDS at 20–40 cm. Importantly, the annual yields were the highest when the SQI values were the maximum. Furthermore, SQ levels within this locale demonstrate a moderate to highly favorable status, ultimately underscoring the area's propitious conditions for crop cultivation. This research provides indispensable theoretical guidance for agricultural practitioners and offers a foundational framework supporting enhanced yields in local grain crops.  相似文献   
936.
    
Exploring the relationship between soil organic carbon (SOC) and different farmland utilization types can contribute to achieving carbon neutrality in agriculture. Over the past few decades, numerous researchers have conducted a multitude of studies on the effects of farmland utilization types on SOC in China, and these studies have yielded a wealth of data from field experiments. However, these experiments are limited in that they lack sufficient quantitative analyses of studies conducted on regional or national scales. In this study, we analyzed the three most common farmland utilization types (paddy field [PF], dry land [DL], and vegetable field [VF]) in China using a national-scale meta-analysis and included data from 108 observations from 28 studies in the field. In this meta-analysis, we conducted three comparisons (control vs. treatment): (a) PF versus DL, (b) PF versus VF, and (c) DL versus VF. The results showed that in comparison (a), DL had a significantly lower SOC than PF (ln R++ = −0.463, 95% confidence intervals [CIs] = −0.580 ~ −0.345), with DL showing 37.1% lower SOC than PF. In comparison (b), although there was no statistically significant difference between PF and VF (ln R++ = −0.078, 95% CIs = −0.167 ~ 0.011), VF had 7.5% lower SOC than PF. In comparison (c), VF had significantly higher SOC than DL (ln R++ = 0.227, 95% CIs = 0.147 ~ 0.307), with VF showing 25.5% higher SOC than DL. It should be noted that the effects of farmland utilization types on SOC content observed in China varied depending on different factors such as the regions, climatic conditions, and cropping systems. In conclusion, SOC content could be affected by farmland utilization types. Therefore, in order to promote the development of low-carbon agriculture in China, it is important to consider farmland utilization types in agricultural production, as well as to consider carbon budgets, food security, and field practices to maximize agronomic and environmental benefits.  相似文献   
937.
    
Mineral mining often results in changes to the soil environment, reducing the sustainability of the surrounding environment. Restoring the physical and chemical properties of soil in post-tin-mining areas on the tropical island of Belitung, Indonesia, has been a laborious process after more than 10 decades of land reclamation. We aimed to determine which parameter of the soil properties was responsible for the slow recovery process and if there were other properties that indicated more rapid changes. We measured the physical, chemical, and biological properties of soils of different periods in the post-tin-mining areas. We sampled soil from three areas: 0, 1, and 6 years after mining and an adjacent natural forest as a reference site. The soil water content, hydraulic conductivity, bulk density, particle distribution, mineral content, and soil microbial composition were measured in the field and analyzed in the laboratory. The soil showed a fine particle loss and despite the absence of clay, water-holding capacity was significantly increased in the 6-year-old soil. Organic carbon increased by 0.2% after 6 years of reclamation. Copper, iron, manganese, and zinc in the soils fluctuated less. Minimal amounts of Pb and Cd were found. Soil bacterial communities shift with land age. Actinobacteria were dominant a few years after mining, while Proteobacteria colonized the mined area after 6 years. This study examined the more profound changes in the soil properties of tropical post-tin-mined land. Soil and bacterial characteristics can be used as markers to monitor the progress of land rehabilitation.  相似文献   
938.
    
Permafrost is one of the essential carbon pools in the world. Due to limited studies on historical soil moisture changes and the coupling relationship between soil moisture and temperature in permafrost regions, significant uncertainty exists in the carbon loss in permafrost predicted by different models under global warming scenarios. Based on the tree-ring width chronology of Pinus sylvestris var. mongholica Litv. growing in the southern edge of the Eurasian continuous permafrost zone, we reconstructed the summer (June–September) 0–1 m soil moisture variations from 1705 to 2009, which could explain 45.6% of the variance in the observed soil moisture. Overall, local precipitation and temperature exhibited statistically significant positive feedback (p < 0.001) to soil moisture before the 1950s, indicating that the warm/humid climate pattern was conducive to soil moisture conservation before the Anthropocene Epoch. However, the effect of temperature on soil moisture has shifted suddenly to negative since the 1950s, implying that the positive soil moisture-temperature relationship during the past three centuries has been disrupted by the unprecedented warming in the Modern Warm Period. Furthermore, we found that the temporal relationship of the soil moisture-temperature (15-year sliding correlation) in the study area is negatively regulated by the global mean temperature variations (p < 0.01). The regime shift between soil moisture and temperature might be attributed to the superimposed influence of natural and anthropogenic factors since the 1950s. Although the warming leads to the melting of the permafrost layer, and thus the increase in soil moisture content, the enhanced evapotranspiration caused by warming up results in more water loss and drier soil. This study provides historical evidence of shifted soil moisture-temperature coupling in the permafrost zone, warning that soil moisture in the permafrost region may further decline under global warming scenarios, thereby affecting vegetation growth and forest carbon sequestration potential.  相似文献   
939.
    
This work proposes a framework for co-designing decision-support tools for sustainable land management and soil protection at multiple scales. Geospatial dashboards, due to their key capabilities in the use of spatial or geospatial information, are quickly gaining traction for planning and policymaking. Developing the decision-support system (DSS) as a transversal system capable of capturing trends in land and soil properties at the local, regional, national, and EU levels has been co-designed with policy stakeholders. This work seeks to link (i) the main goal of the Soil Mission and the UN Sustainable Development Goals (SDGs), to raise awareness and knowledge on soil conditions (ii) and the LANDSUPPORT (LS) project cross-evaluation on how the spatial decision-support system (SDSS) can support policy-related stakeholders and help them to take evidence-based decisions. To achieve this objective, we present the user engagement process to ensure broad testing and evaluation of the LS SDSS's ability to support selected EU policies and soil-related SDGs by testing the LS platform's European scale tools, including an analysis and conformity check of the data delivered by the LS tools and a critical review of results. The indicators were assessed via direct contact with end users, such as semi-structured interviews (SSI) and 184 questionnaires. Results of the test series have been analyzed by the spatial scale per respective tool and performance indicators. We present a unique, integrated, science-based approach to co-create data-driven decision-making with the stakeholders to promote sustainable land management practices. This methodology strives to involve many stakeholders in scientific research, empowering them to participate in the decisions on topics that directly affect them. Public bodies responsible for land policy implementation, environmental stakeholders, spatial planners, and other users have engaged in the process to ensure broad testing of the LS platform from 2020 to 2022. A strengths, weaknesses, opportunities, and threats (SWOT) analysis provided a synthesis of the performance of the LS tools. The testing phase proved the utmost importance of usability, underlining that the mixed method of testing allowing quantitative and qualitative analyses based on the same key indicators proved essential for co-designing SDSS tools to be used by a wide range of stakeholders.  相似文献   
940.
    
Soil organic carbon (SOC) and aggregate stability are the critical factors in evaluate soil quality and carbon sinks in agricultural soils. Especially in complex saline soils containing larges amount of sodium and calcium ions. To quantitatively estimate the importance of salinity factors, SOC fractions, and soil aggregate fractions on SOC contents and the mean weight diameter (MWD), as well as to reveal the transformation mechanism of SOC under the interactions between salinity and straw, a laboratory experiment was conducted on three soils with different salinity, with and without straw addition. The results showed that straw and salinity interactions significantly increased the proportion of large macro-aggregate fractions and the MWD, decreased micro-aggregate fractions, but promoted the conversion of SOC fractions to mineral-associated organic carbon (MAOC) of micro-aggregates in moderately saline soils. The responses of SOC contents and MWD to electrical conductivity (EC1:5) were nonlinear. The exchangeable sodium to calcium ions ratio (E-Na/E-Ca) (%IncMSE = 11.4, p < 0.01), and MAOC contents (%IncMSE = 17.0, p < 0.01) provided the best explanations of SOC contents, while the MWD was more explained by calcium carbonate (CaCO3) contents (%IncMSE = 9.6, p < 0.01), and MAOC/SOC (%IncMSE = 10.5, p < 0.01). The proportion of micro-aggregate fractions was significant drivers of both SOC contents and MWD. The increased MAOC contents was mainly caused by improving the binding sensitivity of aliphatic compounds to salt-related compounds, and the contents of C–C/C–H and C=O functional groups. The findings offer new perspectives into the mechanism of SOC sequestration and sustainable development of moderately saline soils under straw returning in the Hetao area.  相似文献   
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