Proper Grazing Research Articles

Synergy and trade-off between plant functional traits enhance grassland multifunctionality under grazing exclusion in a semi-arid region.

Grazing exclusion is effective in restoring vegetation and ecological services in degraded grasslands within semi-arid regions. Variations in plant functional traits associated with the duration of grazing exclusion can indicate both ecological adaptability of plants and restoration processes of ecosystems. However, research on ecosystem multifunctionality (EMF) under grazing exclusion and restoration mechanisms mediated by plant functional traits is relatively limited. In this study, we calculated EMF based on plant species diversity, above-ground biomass (AGB), below-ground biomass (BGB), storages of soil organic carbon (TSOC), soil nitrogen (TSN), and soil phosphorus (TSP) in grasslands under varying durations of grazing exclusion in the semi-arid Songnen Plain, China, and investigated the trait-based pathways involved in forming EMF. The findings revealed irregular fluctuations in plant species diversity, while AGB, TSOC, TSN, and TSP exhibited a linear increase with grazing exclusion duration. Additionally, BGB initially increased but experienced a slight decline over the 17 years of grazing exclusion (GE17). Notably, EMF peaked at 0.778 in GE17 site. In particular, the proportions of AGB and TSOC in the EMF were higher in grazing exclusion sites than that in grazing site. Leaf area (LA) and leaf weight (LW) were lowest in grazing site and highest in GE17 site. Redundancy analysis indicated that the plant functional traits, including LA, leaf nitrogen content (LNC), and LW, collectively explained a substantial proportion of the variance (70.85%) in ecosystem function indicators. Structural equation modelling analysis revealed a direct impact of grazing exclusion on EMF (P<0.05). However, EMF was remarkably and directly affected by the AGB (P<0.01) that regulated by the trade-off between LW and LNC. In addition, the synergy between LW and LA had an impact on TSP (P<0.01), and further enhance EMF (P<0.05). These findings prominently emphasize the advantageous outcomes of proper grazing exclusion concerning the functional aspects of degraded grasslands. Moreover, they persuasively validate the crucial significance of plant functional traits in relation to the enhancement of EMF. Consequently, this study is capable of providing valuable information for revealing multiple driven mechanisms of grassland EMF in the semi-arid regions.

Comment on "Socio-economic aspects and farming practices of goats in Southern Tunisia" by Chniter et al. (2024).

The following comment is addressed to Chniter et al. (Trop Anim Health Prod 56:220,2024) related to "Socio-economic aspects and farming practices of goats in Southern Tunisia". In their review of socio-economic aspects of goats growing in southern Tunisia, the authors have overlooked or missed some important issues that, in my view, can turn in incomplete (or sometimes confusing) interpretation of the performed data analyses. The following comment is intended to draw attention to (1) the threat and the impact of goat raising on land degradation and the spread of desert-like conditions in a region already prone to desertification, (2) whether goat raising is considered a direct cause or a consequence of desertification and prolonged drought in arid and semi-arid areas located in the northern fringes of the Sahara such as southern Tunisia (Medenine and Tataouine), and (3) the difficulties of implementing proper grazing management in these areas.

Valuation of livestock population and national feed security to enhance livestock productivity in Ethiopia.

Feed is a major input in the livestock industry and covers about 60%-70% of the total cost of producing meat, milk and eggs. Inadequate feed supply in terms of quality and quantity leads to lower production performance in livestock. However, the development of an appropriate livestock production strategy through efficient utilization of existing feed resources could raise the production and per capita consumption of livestock products. Efficiency of feed resource utilization can be measured as the ratio between input to production activities and output (e.g. kg of protein used per unit of meat, milk and eggs produced or hectare of land used per unit of milk produced). This study was designed with the objective of evaluating the livestock population and national feed security to enhance livestock productivity in Ethiopia. To achieve this objective, data were collected from the websites of the Ethiopian Central Statistical Agency from 2007 to 2021, FAO publications and websites, books and journals. The data obtained on different feed resources, livestock population and livestock feed requirement and balance were entered into an MS Excel spread sheet (Excel, 2010) and analysed using the general linear model (PRO GLM) procedure of SAS (2014) and multivariate analysis of covariance. The study results revealed that the livestock population had increased from 58.31 million tropical livestock units (TLU) to 81.10 million tropical livestock units (TLU), and the emission of entericCH4 had increased from 2511.08 Gg/year to 3661.74 Gg/year from 2008 to 2021. The study results also showed that the major available feed resources for ruminants are natural pasture and crop residues, which account for 56.83% (87.56×106 ) and 37.37% (57.57×106 ) of total feed production in the country, respectively. The contribution of concentrate and improved cultivated pasture and feed from permanent crops used as feed sources is very insignificant (3.05% and 1.96%, respectively). The estimated quantity of these feed resources was sufficient to meet the livestock feed requirement in the country in terms of dry matter (DM), digestible crude protein (DCP) and MEJ, which estimated about 153.31×106 t, 4.56×106 t and 1203.97×109 MJ DM, DCP and MEJ, respectively. The estimated livestock feed requirements were 134.62×106 , 4.52×106 , and 918.83×109 in DM, DCP and MEJ, respectively. The supply covered about 114.33, 100.04 and 131.33% of the DM, DCP and MEJ total annual feed requirements of livestock in the country. Hence, the current feed surplus obtained on feed requirements of ruminants and equines can support the nutrient requirements of 500×106 broilers, about 5×106 bulls, about 50×106 small ruminants or 3×106 crossbred lactating dairy cows, yielding 10L of milk per day. The findings of study indicated that natural pasture and crop residues cover a major proportion of the annual feed supply in the country. Therefore, proper grazing management, feed conservation practices, improving grazing land vegetation through clearing invasive species, replacing the grazing land with an improved grass and legume mixture, effective collection, conservation and proper utilization of crop residues, and other alternative options such as the use of chemical, physical and biological treatments to improve the nutritive value of fibrous feed should be practiced. More effective extension services and farmer training are also required to increase feed productivity and, hence, human development.

Influence of Grazing on Canola Grain, Canola Forage Yield, and Beef Cattle Performance

Interest is increasing in grazing winter canola (Brassica napus) as an alternative crop in winter wheat (Triticum aestivum) rotations in the Southern High Plains (SHP) of the USA and similar environments. In this stidy, winter cereal rye (Secale cereale) and winter canola pastures (forage) were compared for two winter growing seasons at New Mexico State University’s Rex E. Kirksey Agricultural Science Center at Tucumcari, NM, USA, to determine the relative effect of pasture type on late-gestation beef cows and growing yearling cattle, along with the effect of grazing on canola grain production. Canola grain yields were reduced by 25% when canola was grazed until removal approximately one month after grazing was initiated, but before the onset of rapid regrowth after winter (641 vs. 486 kg grain ha−1 for never grazed or grazed canola, respectively, p &lt; 0.0256). No differences existed for forage mass, nutritive value, or animal performance, although forage mineral composition of canola could be a concern. Grazing winter canola as a dual-purpose crop in the SHP and similar environments is feasible when proper grazing management is applied; producers should anticipate a 20–25% reduction in grain yield, but expect animal gains to offset that loss.

Constraints Affecting the Welfare of Domestic Sheep Grazing in the Natural Pasture

The sheep like other animals need more and more welfare to produce meat of good quality, Sheep welfare problems primarily arise from mutilations, lameness, transportation, and disease. With proper grazing, breeding, and husbandry practices, most health issues in sheep can be resolved or avoided. Grazing involves seeking and choosing feed as well as grabbing and consuming it. The manner in which ruminants or grazing animals grip and consume forages varies. These variations are connected to the sorts of fodder that various ruminants prefer. Heat stress, cold stress, weariness, prolonged thirst, prolonged hunger, hampered movement, movement restrictions, resting issues, social stress, pain, fear, and distress are the welfare types that sheep may encounter during caged, all issues due to shortage of welfare, this results in sheep inside the body that acts as a substance that cannot be used in the metabolic processes and is difficult to get rid of the animal is able to get rid of these substances accumulated inside the body that are difficult to get rid of the presence of natural toxins can be produced through the accumulation of some chemical substances and elements that the animal gets from the food. They come as residues from deteriorated cells or some vital processes in the body.

Recovery through proper grazing exclusion promotes the carbon cycle and increases carbon sequestration in semiarid steppe

Grazing exclusion changes soil physical-chemical characteristics, rapidly affects microbial community composition and function, and alters biogeochemical processes, e.g., carbon (C) cycle, over time. However, the temporal dynamics of CO2 emission and CH4 uptake during grassland restoration chronosequences remain poorly understood. We investigated soil CO2 emission and CH4 uptake, the genes related to CO2 and CH4 production and reduction (cbbL, cbbM, chiA, and pmoA), and associated microbial communities under different durations of grazing exclusion (0, 7, 16, 25, and 38 years) to reveal the mechanisms and potential of soil CO2 emission and CH4 uptake in a semi-arid steppe. The results showed that a proper exclusion period could significantly improve soil physical-chemical conditions, vegetation community, and soil C-cycling. The abundance of C-cycling functional genes (cbbL, cbbM, chiA and pmoA), CH4 uptake and CO2 emission rates showed a single-peak pattern with increasing duration of grazing exclusion, peaking at 16 years and then decreasing in the period between 25 and 38 years, indicating that the effect of exclusion weakened when the exclusion period was too long. The changes in C-cycling functional genes and microbial communities are primarily influenced by aboveground net primary productivity (ANPP), and are associated with CO2, CH4, soil water content (SWC), and soil organic carbon (SOC). Structural equation modeling showed that increases in SOC content and pmoA abundance caused by an increase in ANPP accelerated CO2 emission and CH4 uptake rates, respectively. Our results provide valuable insights into the critical role of grazing exclusion in promoting grassland restoration and carbon sequestration, and have potential implications for sustainable land management practices.

Effects of climate change on community based grazing lands management: A case study of the border between Nigeria and Niger Republic

In recent years, climate changes have had serious and unprecedented effects in Nigeria and Niger Republic. These changes range from a rapid decrease in forest resources to social and economic effects with obvious environmental repercussions. This paper examined the effect of climate change on community based grazing land management between the border of Nigeria and the Niger Republic. The focus was made on identifying activities carried out in the area, identifying herders’ encroachment routes and the perceived occurrence of climate change. Thus, data from Focus Group Discussions (FGD) and Questionnaire derived from the inhabitants were collected and analyzed. A total of 1,009 questionnaires out of the 1,020 given were used to collect data for the study. The results revealed that various forms of changing climatic patterns force arable farming into more and more marginal areas. When there is heavy pressure on grazing lands, the animals consume palatable vegetation faster than it can generate, and eventually, no vegetation remains. Continuing overgrazing is detrimental in the study area because it reduces primary productivity, impedes plant growth and survival and consequently alters species composition of the grasses, shrubs and forbs that provide livestock with food. The study further revealed that moderate grazing pressure increased plant diversity and soil and land health. Therefore, good pasture management is a remedy to sustainable utilization, among which proper grazing management serves as the key element of sustainable rangeland restoration. The study further recommends that the conservation of grazing land is the responsibility of all.

A Framework for Quantifying the Strength of Partnerships between Agricultural Cooperatives and Development Actors: A Case Study in Saudi Arabia.

The issue of the agricultural cooperatives' sustainability in developing their businesses is gaining increasing prominence. Building partnerships between development actors and agricultural cooperatives has been considered an effective strategy for supporting financial capital and addressing sustainability issues collectively. Therefore, this study aimed to address the features and strengths of 33 partnerships established between the Beekeeping Cooperative Association in Al-Baha, Saudi Arabia, and other actors between 2016 and 2021. The analysis of the collaborations was based on six criteria: motivations, partnership planning, outputs, governance practices, outcomes, and sustainability of a partnership. Furthermore, we developed a weighted scoring model to control variable selection and submit the strength of each partnership. The findings indicated that most collaborations (45.5%) were signed with the private sector. Furthermore, the honey value chain development was the most frequent reason (69.7%) attracting the partners to engage in the partnerships. Some of the most critical environmental objectives targeted by the partnerships examined were enhancing bee habitat by the diversification of pasture species, management to increase the flowering period, and proper grazing management. All partners achieved their individual goals jointly in 54.5% of the partnerships analyzed. In terms of a partnership's strength, the findings also revealed that only three partnerships (9.1%) were characterized as strong partnerships. This study provides a better understanding of how agricultural cooperatives collaborate with other actors and a basis for assessing the strength of the partnerships. Such information is crucial for developing relevant policies to encourage cooperatives to engage in future sustainability partnerships.

Photosynthetic Behavior of Argania spinosa (L.) Skeels Induced under Grazed and Ungrazed Conditions

The endemic Moroccan species Argania spinosa is considered the most grazed tree species in its distribution area. Since grazing exerts an important effect on plant performances, we attempted to explore the impact of grazing on A. spinosa. Thus, we performed a comparative field experiment where seasonal variations of gas exchange, photochemical efficiency, relative water content, photosynthetic pigment content, and stomatal features were assessed in grazed and ungrazed trees. The net photosynthetic rate was increased in grazed trees in spring and autumn, the favorable seasons. Enhancement of photosynthetic performance may be due to the high stomatal conductance registered in grazed trees. This mechanism may compensate for the lost leaf area, in order to recover from grazing stress. In addition, grazed trees exhibit a better photochemical efficiency, use water more economically and show lower oxidative stress. However, results obtained in summer show that the compensation mechanism could be limited by summer drought. Since the key to preserving the future of forests is sustainable forest management, our results suggest that proper grazing management can be a control tool to increase plant performance and improve species resilience.

40 Ecosystem Services Provided by Grassland Ecosystems in Southeast USA

Abstract Ecosystem services are benefits people obtain from ecosystems. They are categorized in provisioning (e.g., animal products, fiber, timber, fruits, pods), supporting (e.g., nutrient and water cycling, soil formation, photosynthesis), regulating (e.g., climate regulation, water purification, pollination), and aesthetic/cultural (e.g., recreation/ecotourism). Grasslands are one of the major agroecosystems in Southeast USA. They provide a multitude of ecosystem services (ES) in all these categories. Grassland management impacts its ability to deliver ES. Management practices such as grazing management, fertilizer application, and diversification of vegetation cover are key aspects to consider. Proper grazing management balancing herbage mass and livestock weight (i.e., herbage allowance) results in net soil C accumulation. In fact, grasslands are one of the most important sinks of soil C. Fertilizer application might have numerous roles in the delivery of ES, some of them beneficial and some others detrimental. Benefits of applying fertilizer include increasing primary productivity and, if accompanied by proper grazing management, can result in greater livestock performance. It may also help to decay recalcitrant litter from C4 grasses and enhance nutrient cycling. Detrimental effects include the use of fossil fuels during the manufacturing process and, if applied in large amounts, might lead to nitrate leaching and denitrification. Integrating forage legumes has potential to enhance the delivery of ES by adding N via biological N fixation, enhancing nutrient cycling, improving livestock gains, and providing a better habitat for pollinating insects. Diversifying functional groups and increasing species richness is a possible way to enhance resource utilization both in space and time, reducing the need for off-farm inputs and maintaining and/or enhancing productivity. Grasslands produce far more than beef and milk. They provide ES that benefit the entire society. Mechanisms to compensate landowners must be put in place to recognize the value they are providing for the entire society.

Evaluating Release Strategy for Translocated Northern Bobwhites in Cross Timbers Ecoregion of Texas: A Pilot Study

Northern bobwhite (Colinus virginianus) population decline is largely driven by the loss, fragmentation, and degradation of grassland habitats. Translocation is used to reintroduce or augment populations in fragmented landscapes where natural dispersal is inhibited. Northern bobwhites have been successfully translocated in the southeastern portion of their range, but outcomes of translocations in western ranges have been mixed. Our objective was to conduct a pilot study to test the feasibility of translocating northern bobwhites to a restored, but isolated, habitat in the Cross Timbers ecoregion of Texas, USA and to evaluate the influence of release strategy for improving northern bobwhite site fidelity and survival post-release. The release property was restored through brush management, native species seeding, and proper grazing management. We trapped and translocated 84 northern bobwhites from source populations in the Rolling Plains and Edwards Plateau ecoregions during March 2015. Coveys were assigned to either delayed or immediate release treatment. We radio-collared all hens (n = 40; 11 adults; 29 juveniles) and evenly divided the sample between delayed and immediate releases. Delayed release coveys were held on the release site for 4 weeks in a Surrogator® (Wildlife Management Technologies, LLC). We trapped and radio-collared resident hens (n = 15) in March and monitored all hens through breeding season (March–August; 180 days). We implemented a 2-state (alive or dead) multistate model in Program MARK to analyze survival as a function of the release treatment, resident status, and age. We found no evidence that survival differed between translocated and resident hens (β = 0.48, standard error [SE] = 0.38), release treatments (β = 0.10, SE = 0.40), or age (β = -0.16, SE = 0.54). Daily survival for all hens was 0.99 (SE = 0.009) and breeding season survival was 0.19 (SE = 0.08). Four (20%) immediate, 2 (10%) delayed release, and 0 resident hens dispersed off-property. Translocated and resident hens survived at similar rates, indicating that translocation may be a feasible management strategy for augmenting a northern bobwhite population on restored habitats in the Cross Timbers ecoregion although overall survival was low. We did not find evidence that delayed release improved daily survival post-release, but our small sample size may have prevented us from detecting a difference. However, delayed release birds were effectively sheltered from predation during peak raptor migration. Additional research is needed to fully understand population dynamics and implications of release strategy for translocated northern bobwhite.

Carcass Traits, Meat Quality, and Volatile Compounds of Lamb Meat from Different Restricted Grazing Time and Indoor Supplementary Feeding Systems

This study was conducted to investigate the carcass traits, meat quality, and volatile compounds of growing lambs under different restricted grazing time and indoor supplementary feeding systems. Fifty 3-month-old male Tan lambs (with similar body weight) were divided into five groups randomly according to grazing time 12 h/d (G12), 8 h/d(G8), 4 h/d(G4), 2 h/d (G2), and 0 h (G0, indoor supplementary feeding). Animals were slaughtered at the end of the experiment, and the longissimus thoracis (LT) samples were collected for further analysis. The results indicated that indoor supplementary feeding improved the percentages of carcass fat and non-carcass fat of pre-slaughter weight (PSW) and decreased the cooking loss of lamb meat. Grazing for 8 h/d or 2 h/d enhanced PSW, carcass, and meat percentages of PSW. Lambs grazing for 2 h/d with supplement and indoor supplementary feeding lambs had a higher level of intramuscular fat and lightness (L*) value and lower cooking loss in the LT muscle, but higher yellowness (b*) and fat content were found in indoor supplementary feeding lambs. More categories of volatile compounds were identified in meat from grazing lambs than from indoor supplementary feeding lambs, but lower content of aldehydes and total volatile flavor compounds was detected in grazing lambs. Overall, the results demonstrated that the feeding system is a main factor that affects lamb meat quality, and proper grazing time can improve the quantity and quality of lamb meat and provide meat with different flavors to the consumers.

Temporal Changes in Association Patterns of Cattle Grazing at Two Stocking Densities in a Central Arizona Rangeland

Simple SummaryMonitoring changes in the utilization of forages across rangelands can be time consuming and difficult with untrained personnel. The use of real time positioning for cattle is becoming commercially available with the improvements in technology. The objective of this case study was to identify the changes in livestock social associations and spatial location at two stocking densities throughout a six-week grazing period. Both pastures used similar sized herds with 35 and 29 animals tracked with global positioning systems set at 30-min intervals. A half-weight index value was calculated for each pair of tracked cattle to determine the proportion of time that cattle were within 75 m and 500 m of each other. Throughout the study, forage utilization increased from 5 to 24% and from 10% to 20% and forage mass decreased from 2601 kg ha−1 to 1828 kg ha−1 and 2343 kg ha−1 to 1904 kg ha−1, in the high stocking density pasture and low stocking density pasture, respectively. Utilization of forages throughout the trial forced cattle to disperse and travel further from water sources to find new feeds. Real-time GPS tracking has the potential to remotely detect changes in animal spatial association, identify when cows disperse, and improve recognition for the need of pasture rotation to avoid rangeland degradation.Proper grazing management of arid and semi-arid rangelands requires experienced personnel and monitoring. Applications of GPS tracking and sensor technologies could help ranchers identify livestock well-being and grazing management issues so that they can promptly respond. The objective of this case study was to evaluate temporal changes in cattle association patterns using global positioning system (GPS) tracking in pastures with different stocking densities (low stocking density [LSD] = 0.123 animals ha−1, high stocking density [HSD] = 0.417 animals ha−1) at a ranch near Prescott, Arizona. Both pastures contained similar herd sizes (135 and 130 cows, respectively). A total of 32 cows in the HSD herd and 29 cows in the LSD herd were tracked using GPS collars at location fixes of 30 min during a 6-week trial in the summer of 2019. A half-weight index (HWI) value was calculated for each pair of GPS-tracked cattle (i.e., dyads) to determine the proportion of time that cattle were within 75 m and 500 m of each other. Forage mass of both pastures were relatively similar at the beginning of the study and forage utilization increased from 5 to 24% in the HSD pasture and increased from 10 to 20% in the LSD pasture. Cattle in both pastures exhibited relatively low mean association values (HWI < 0.25) at both spatial scales. Near the end of the study, cattle began to disperse likely in search of forages (p < 0.01) and travelled farther (p < 0.01) from water than during earlier periods. Real-time GPS tracking has the potential to remotely detect changes in animal spatial association (e.g., HWI), and identify when cows disperse, likely searching for forage.

Effect of Grazing Intensities on Soil N2O Emissions from an Alpine Meadow of Zoige Plateau in China

The alpine meadow of Zoige Plateau plays a key role in local livestock production of cattle and sheep. However, it remains unclear how animal grazing or its intensity affect nitrous oxide (N2O) emissions, and the main driving factors. A grazing experiment including four grazing intensities (G0, G0.7, G1.2, G1.6 yak ha−1) was conducted between January 2013 and December 2014 to evaluate the soil nitrous oxide (N2O) fluxes under different grazing intensities in an alpine meadow on the eastern Qinghai–Tibet Plateau of China. The N2O fluxes were examined with gas collected by the static chamber method and by chromatographic concentration analysis. N2O emissions in the growing seasons (from May to September) were lower than that in non-growing seasons (from October to April) in 2013, 1.94 ± 0.30 to 3.37 ± 0.56 kg N2O ha−1 yr−1. Annual mean N2O emission rates were calculated as 1.17 ± 0.50 kg N2O ha−1 yr−1 in non-grazing land (G0) and 1.94 ± 0.23 kg N2O ha−1 yr−1 in the grazing land (G0.7, G1.2, and G1.6). The annual mean N2O flux showed no significant differences between grazing treatments in 2013. However, there were significantly greater fluxes from the G0.7 treatment than from the G1.6 treatment in 2014, especially in the growing season. Over the two years, the soil N2O emission rate was significantly negatively correlated with soil water-filled pore space (WFPS) and dissolved organic carbon (DOC) content as well as positively correlated with soil available phosphorus (P). No relationship was observed between soil N2O emission rate and temperature or rainfall. Our results showed that the meadow soils acted as a source of N2O for most periods and turned into a weak sink of N2O later during the sampling period. Our results highlight the importance of proper grazing intensity in reducing N2O emissions from alpine meadow. The interaction between grazing intensity and N2O emissions should be of more concern during future management of pastures in Zoige Plateau.

Forage Quantity and Quality Dynamics Due to Weathering over the Dry Season on California Annual Rangelands

Livestock obtain forage by grazing on rangeland. In California annual rangelands, residual dry matter is commonly used to determine proper grazing levels. Rangeland forage biomass and quality can degrade dramatically during the dormant summer period. We examined 25 sites across an annual rainfall gradient (183–492 mm) over 3 contrasting rainfall yr (2015–2017) that varied from 57% to 152% of average annual precipitation. Overall fractional biomass loss was 54.4% (range = 46.5–61.5%) with greater fractional losses occurring in dry years. Biomass losses were related to the amount of peak standing crop and plant composition—both a function of annual precipitation. Fractional seasonal losses from the peak standing biomass in 2015 = 962 kg/ha (61.5% seasonal; 9.7% monthly), 2016 = 1 541 kg/ha (55.0% seasonal; 8.7%monthly) and 2017 = 1 923 kg/ha (46.5% seasonal; 7.3%, monthly). Forage quality metrics were strongly affected by summer weathering processes. Crude protein concentrations decreased by 33.6%, 27.7%, and 21.0% in 2015, 2016, and 2017, respectively. In contrast, relative concentrations of fiber and lignin (acid detergent fiber [ADF] = cellulose + lignin) and in the weathered biomass showed increases for ADF: 44.6% (2015), 32.2% (2016), and 24.1% (2017). Increased lignin varied: 3.4% in 2015, 23.9% in 2016, and 28.0% in 2017. While ADF and lignin concentrations (weathered biomass, kg/ha) increased during the weathering process, the standing stock decreased by 39.3% (ADF) and 46.6% (lignin), compared with overall weathered biomass loss of 54.4% and CP loss of 67.1%. The significant loss of aboveground biomass and forage quality as weathering processes occurred throughout the dry summer period affects livestock grazing strategies. Forage biomass and nutrient losses through the dry season should be considered when determining grazing strategies to achieve proper residual dry matter levels and nutrient supplementation regimes before the onset of the rainy season.

Grazing intensity induced alternations of soil microbial community composition in aggregates drive soil organic carbon turnover in a desert steppe

Grazing is the primary land-use strategy for livestock production in grasslands, which regulate the health of grassland ecosystems. However, our understanding of grazing-induced changes in soil microbial community structure and their links to organic carbon (C) in soil aggregates is limited. By using a long-term enclosed grazing desert steppe, we examined impacts of different grazing intensity on the diversity and composition of soil microbial community in different aggregates and their contribution to soil organic C (SOC) turnover. The results showed that 15-year grazing induced a notable increase in the SOC content of the large macroaggregate (> 2 mm) and silt and clay (SC: < 0.053 mm) fractions, but did not change bulk soil organic C content. Soil prokaryotic communities were significantly impacted by grazing intensity and aggregates fractions (p < 0.01). Microaggregate (0.053−0.25 mm) and the SC fraction hosted relative more sequences of Acidobacteria, Gemmatimonadetes, and Rokubacteria than macroaggregates (0.25−2 mm), but relatively less sequences of Actinobacteria and Bacteroidetes. Co-occurrence network analysis revealed that microaggregates hosted a much more complex network and harbored more keystone taxa than macroaggregates and the SC fraction. Gemmatimonadetes was the dominant phylum (relative abundance ∼9%) and keystone taxa largely belong to this phylum, and its abundance was positively correlated with the level of SOC. Overall, grazing practice altered the soil prokaryotic community, which led to increase in the organic C level in the large macroaggregate and SC fractions, the early indicators of change in SOC dynamics. Together, our findings suggest that removing livestock from these lands would reduce SOC with probable impact on the productivity of the desert steppe and that proper grazing is an import factor of long-term sustainability of the desert steppe.

Enhancing landowner adoption of the Natural Resource Conservation Service’s recommended beef cattle grazing management practices

Water has a significant role in society, whether through human consumption or agricultural use. The Lavaca Watershed is an agricultural community affected by nonpoint source pollution, and water quality protection is of high concern. Beef cattle operations are linked to nonpoint source pollution which contaminates surrounding water sources. If proper grazing management practices are not used, wastes from the operation impair water quality in the area. Landowners should use proper stocking rates and implement best management practices to benefit land and water quality in addition to overall operation profit. Females reported a higher intention to adopt, indicating these respondents are more open to practice changes on their own operation. Results indicated a need for the Natural Resource Conservation Service (NRCS) and Texas Soil and Water Conservation Board to conduct further outreach to increase interaction with landowners. NRCS agencies could help increase the use of water conservation plans and inquiries by making this clear to current landowners participating in their program as well as potential clients by sending informational flyers or speaking at local organizational gatherings. The importance of adopting water management practices and barriers to adoption are ongoing global concerns.

Enhancement of N2O emissions by grazing is related to soil physicochemical characteristics rather than nitrifier and denitrifier abundances in alpine grassland

Grazing can degrade grassland soil and increase nitrous oxide (N2O) emissions, but the underlying mechanism is poorly understood. We investigated the relationship of soil N2O emission with nitrifying enzyme activity (NEA), denitrifying enzyme activity (DEA), and the abundances of N2O-producing and N2O-reducing functional genes, in response to three grazing intensities (none, light, intensive) over two growing seasons on an alpine grassland on Kunlun Mountain in semi-arid North China. Compared to the non-grazed control, light and intensive grazing treatments increased the 2-yr total N2O emissions by 27.5% and 68.1%, respectively. Daily N2O flux rate correlated positively with soil water-filled pore space (WFPS), temperature, and dissolved organic carbon (DOC) but not with the abundances of nitrifiers (AOB, AOA, Nitrobacter-like nxrA), nitrate reducers (narG) and denitrifiers (nirS, nirK, and nosZ). These results suggest that soil environmental factors rather than nitrifier, N2O-producer and N2O-reducer abundances were more important in determining the grazing enhancement of N2O emissions from the alpine grassland in semi-arid areas. The abundance of AOB and Nitrobacter-like nxrA but not AOA correlated positively with NEA, indicating they are good indicators for the potential nitrification in this arid alpine grassland. Reducing grazing intensity from intensive to light resulted in more above-ground biomass and N uptake in both years and less N2O emissions in 2018. These results highlight the importance of establishing a proper grazing intensity to reduce N2O emissions from the degraded grassland while maintaining productivity for livestock.

Floristic diversity and stocking rate in tropical dry forest secondary vegetation used for grazing

The natural process of ecological regeneration in tropical regions in conjunction with local livestock management practices creates grazing environments with high floristic diversity and structural complexity. Yet, these environments are being neglected despite the opportunities and benefits for domestic herbivores. Voisin grazing (VG) is better in such highly biodiverse environments, as this management system seeks to improve forage utilization by coupling forage allowance with livestock needs for forage, using small paddocks, high stock densities over short occupation periods, and allowing plants to fully recover after grazing. Floristic diversity, biomass and stocking rate were assessed in sites having tropical dry forest secondary vegetation undergoing grazing. Six sites having extensive seasonal grazing were studied by placing 10 × 10 m2 quadrats across sites to list woody species and nested 2 × 2 m2 frames for listing herbaceous vegetation. The response of vegetation to Voisin grazing (VG) was evaluated in one of the six sites (split into 15 paddocks having 400-m2 each). A total of 191 species (from all sites) including 50 potential forage species were listed. Quadrats were classified into two groups, one contained more preserved vegetation dominated by woody species, and the other a less preserved group dominated by herbaceous and shrub species. Available forage biomass across sites ranged from 1000 to 1200 kg DM ha−1 (30–70% woody biomass), supporting low stocking rates (0.2–0.3 AU ha−1). In the site where VG was implemented, most of the identified species were forage (56/58). After one year of VG, the most productive paddocks (2500–3800 kg DM ha−1) were dominated by forbs and the least productive ones (800–2000 kg DM ha−1) were dominated by woody species, yielding an overall stocking rate of 1.2 AU ha−1. Based on forage botanical composition, three groups of paddocks were identified: 1) dominated by grasses, 2) heterogeneous forage diversity, and 3) dominated by forbs and shrubs. Pastures recovered in 47–89 d during the 2017 rainy season, 50–123 d during the transition to the dry season, and 210–290 d during the 2018 dry season. Secondary vegetation provides high floristic diversity and a large number of forage plant species, but low forage yield and stocking rates. Yet, implementation of a proper grazing system such as VG gradually enhances yield and stocking rates.

Herbage responses of Tamani and Quênia guineagrasses to grazing intensity

AbstractNew forage cultivars require defoliation studies for recommending proper grazing management. Our objective was to characterize herbage accumulation (HA), plant‐part composition and nutritive value of guineagrass [Megathyrsus maximus (Jacq.) B. K. Simon &amp; S. W. L. Jacobs] rotationally stocked under two grazing intensities. The experimental design was a randomized complete block with three replicates of a 2 × 2 factorial arrangement of two guineagrass cultivars (‘BRS Quênia’ and ‘BRS Tamani’) and two grazing intensities. Heavy (HGI) and lax (LGI) grazing intensities were imposed as post‐grazing stubble heights: 15 and 25 cm for Tamani, and 20 and 35 cm for Quênia, respectively. The experimental period was from March 2015 to March 2017, comprising eight seasons (autumn 2015, winter 2015, spring 2015, summer 2016, autumn 2016, winter 2015, spring 2016, and summer 2017). In the spring 2016 and summer 2017, pre‐grazing HM was sampled as two strata above the stubble height, each comprising 50% of the sampled height (upper and lower stratum). Total herbage accumulation was similar across years, cultivars, and intensities (16,810 kg DM ha−1). Quênia and Tamani had the greatest HA during summer. The leaf proportion was least in the HGI pastures. Under HGI, the lower stratum of both cultivars had the greatest stem proportion and the least nutritive value. The greatest herbage CP concentration and the least NDF, ADF, iNDF and LIG concentrations occurred in the upper stratum. Based on these results, 35 and 55 cm are recommended as target heights for initiation of grazing, and 25 and 35 cm as post‐grazing stubble heights for Tamani and Quênia, respectively.