Background: Grazing lands provide numerous ecosystem services, including the capacity to store large amounts of soil carbon (C); however, our understanding of the factors affecting soil C responses to management is inadequate.
Methods: In this paper, we synthesized information about the impacts of grazing land management on soil C within the southeastern region of the United States.
Results: Most studies (68%) demonstrated that proper management increased soil C stocks with an average C accumulation rate of 1.4 Mg C ha−1 year−1. The remaining (32%) studies showed no effect of management on soil C. None of the studies reported negative impacts of management on soil C. The largest increase in soil C (8Mg C ha−1 year−1) was associated with the conversion of cropland to pastureland while overseeding legumes into grass pastures resulted in the lowest C sequestration rates (0.2 Mg C ha−1 year−1).
Conclusions: Considering the rates of soil C accretion and the extensive area occupied by grazing lands, data in this synthesis confirm that the adoption of improved management practices can increase soil C sequestration in the southeastern United States. In addition, because most improved management practices can also have co-benefits, they may be favorable for forage and livestock production and other ecosystem services.
Background: Cattle farming plays a pivotal role in Africa’s agricultural and livestock sector, poised for growth due to population expansion and rising per capita consumption of animal-sourced food. Forages are a primary source of feed for dairy cattle, significantly impacting production costs.While local forage varieties are preferred by dairy farmers, there has been an increase in the adoption of improved forages in recent years. However, the overall adoption rate is still low, for example, due to underdeveloped forage seed markets.
Methods: This study describes the dynamics, challenges, and potential of these markets in Kenya and selected East African countries, focusing on (i) market evolution over the past decade, (ii) forthcoming market prospects, and (iii) bottlenecks and opportunities for improvement. Data were gathered in 2022 through qualitative interviews with stakeholders representing six segments of the forage seed sector across six countries.
Results: We found a sustained growth of the improved forage seed market in recent years. The main challenges for further growth are high seed prices, regulatory difficulties, and limited producer knowledge.
Conclusions: The findings unveil positive dynamics in the region’s forage seed market, fueled by the engagement and determination of stakeholders who recognize the manifold benefits that it holds for both the dairy industry and economic growth. The realization of this market’s potential requires addressing prevailing challenges, including elevated seed costs, intricate variety registration processes, and a pervasive lack of awareness among farmers.
Background: Local sward dieback, especially in grasslands on peat soil, in response to the extreme 2018/2019 drought demonstrates climate vulnerability of intensive grasslands in northern Central Europe.
Methods: We explore the influence of microtopography, that is, the withinfield mosaic of depressions and elevated patches, on soil volumetric moisture content, standing biomass and biomass crude protein (CP) and fibre content in intensively managed grassland on peat soil in a moist year (2021) and a dry year (2022) for quantifying small-scale spatial heterogeneity within a field.
Results: We found high within-field variation in soil moisture, biomass and forage quality and a moisture dependence of productivity that was stronger in the dry year. CP ranged from 10% to 25% within a field, being lower in moist depressions than elevated patches in the wet (but not in the dry) summer.
Conclusions: The moister depressions help to limit the overall productivity decline in dry summers, whereas, in moist summers, the higher dry patches produce more protein-rich forage than the depressions, where productivity is higher but quality is lower. We recommend adapting grassland management to this heterogeneity through spatially differentiated management regimes in order to better cope with an increasingly drier and more variable climate.
Background: Long-term overgrazing has led to severe degradation of grasslands, posing a significant threat to the sustainable use of grassland resources.
Methods: Based on the investigation of changes in functional traits and photosynthetic physiology of Stipa breviflora under no grazing, moderate grazing, and heavy grazing treatments, the changes in expression patterns of genes and proteins associated with different grazing intensities were assessed through integrative transcriptomic and proteomic analyses.
Results: Differentially expressed genes and proteins were identified under different grazing intensities. They were mainly related to RNA processing, carbon metabolism, and secondary metabolite biosynthesis. These findings suggest that long-term grazing leads to molecular phenotypic plasticity, affecting various biological processes and metabolic pathways in S. breviflora. Correlation analysis revealed low correlation between the transcriptome and the proteome, indicating a large-scale regulation of gene expression at the posttranscriptional and translational levels during the response of S. breviflora to grazing. The expression profiles of key genes and proteins involved in photosynthesis and phenylpropanoid metabolism pathways suggested their synergistic response to grazing in S. breviflora.
Conclusions: Our study provides insight into the adaptation mechanisms of S. breviflora to grazing and provides a scientific basis for the development of more efficient grassland protection and utilization practices.
Background: Grasslands are the primary source of forage for ruminants. Legal restrictions on nitrogen fertilization force farmers to optimize nitrogen use efficiency (NUE) of grassland and protein quality in grass silage.
Methods: The present study included grassland data from 10 dairy farms in Flanders. For each grassland field, the presence of clover was determined based on the seed mixture composition. Soil and manure were sampled before the first application and analyzed to determine plant available N content. The annual NUE was calculated for each field possible (n = 28). Prewilted grass samples were taken just before ensiling (n = 65) and grass silage samples (n = 41) were collected from the same fields.
Results: Clover fields demonstrated improved NUE due to a lower nitrogen input from fertilizers compared to pure grassland fields (75 vs. 265 kg ha−1). The protein quality of the grass silage was positively correlated with the organic matter digestibility, sugar content, and dry matter content of the prewilted grass. Conversely, crude ash content had a negative effect.
Conclusions: These findings underscore the importance and potential of clover and the practical feasibility of optimizing grassland management to improve both NUE in grasslands and protein quality of the silage.
Background: Grasslands provide a wide range of ecosystem services (ESs). However, there is currently no method for easily diagnosing the level of ESs produced. Our aim was to develop ES indicators based on botanical surveys, which are readily available data and integrative of grassland spatiotemporal variability.
Methods: Based on academic knowledge and expertise, we identified several simple vegetation criteria that we aggregated using a multicriteria analysis tool to construct indicators of the level of ESs provided by grasslands. In this study, the indicators were calculated from over 2000 botanical surveys spread over a wide biogeographical gradient.
Results: Analyses of correlation between the various indicators show that “forage supply” and “diversity conservation” were not correlated. “Forage availability” and “nitrogen availability for the vegetation” were positively linked together and negatively linked to the robustness of the plant community to extreme events. A temporal approach highlights that the “biodiversity conservation” score decreased from 1970 to 2010 and that “nitrogen availability for the vegetation” was lower in 1970 and 1980 than in 2000 and 2010.
Conclusions: These results show that our aggregation method based on a large data set of botanical surveys could be appropriate for studying temporal dynamics of ESs.
Background: Standing root biomass stocks are larger in the perennial grain intermediate wheatgrass (IWG; Thinopyrum intermedium [Host] Barkworth and Dewey) than annual spring wheat (Triticum aestivum L.). However, previous studies have not separated root growth from root decomposition, which presents a significant gap in our understanding of how roots can contribute to soil organic carbon (C) accrual or other soil properties through time.
Methods: We used paired sequential coring and root ingrowth cores to measure standing root stock, new root production, root decomposition, and decomposed root C and N from 0 to 15 cm soil depth of 1-year-old IWG (IWG-1), 2-year-old IWG (IWG-2), and annual spring wheat.
Results: Standing root stock was 3.2–6.5 and 6.3–9.9 times higher in IWG-1 and IWG-2 than wheat. Total root production was 1.7 times greater in IWG-1 than IWG-2. Conversely, root decomposition almost doubled from 1.39 to 2.43 kgm−3 between IWG-1 and IWG-2.
Conclusions: In IWG, decreased root production and increased root decomposition with stand age suggest a change in growth strategy that could reduce the contribution of root-derived C to stabilized soil C pools as IWG stands age.