Pasture Growth Research Articles

Phosphorus supplementation improves the growth and reproductive performance of female Brahman cattle grazing phosphorus-deficient pastures in the Victoria River District, Northern Territory, Australia

Context There is a paucity of information on the responses to phosphorus (P) supplementation of breeder herds grazing P-deficient rangelands in northern Australia. Aims A study examined the production and economic benefits of P supplementation of Brahman females grazing P-deficient pastures in the Northern Territory (NT) of Australia. Methods Two treatment groups (initially n ~ 90) grazed two similar P-deficient paddocks for 5 years after weaning (at approximately 6 months of age). Management was the same except that the loose lick mineral supplement either contained P (+P) or did not contain P (−P). Performance attributes were measured from commencement until after the cows had the opportunity to calve during three successive annual cycles. Key results The cows in the +P treatment were overall heavier (P < 0.001), taller (P < 0.001) and had higher plasma inorganic P (PiP) concentrations (P < 0.001) than did those in the −P treatment at every measurement date after the first wet season. Pregnancy rates in lactating cows were 25%, 39% and 63% units higher (P < 0.01) in +P in 2017, 2018 and 2019 respectively and overall average weaner weight was 33 kg heavier (P < 0.001) in +P. Due to higher weaning rates and heavier weaning weights, +P produced about AU$39 365 more value of weaners per 100 heifers allocated to each treatment than did −P over the first three calf crops. The cumulative mortality rate was 12% higher in the −P over the 5 years (14.8% vs 2.2%, P < 0.01), and would have been even higher if at-risk −P cows had not been fed additional supplements. Return on investment calculations indicated that each AU$1 spent on P supplement returned AU$4.98 in value of extra calves weaned and AU$7.88 in extra total liveweight increase over the 5 years of the study. Conclusions The large production and financial benefits from P supplementation observed in this study are relevant to most northern Australian properties where soils are P deficient, although the magnitude of response is likely to vary depending on the level of P deficiency. Implications The large production and economic benefits from P supplementation in this study demonstrated the importance of P supplementation for breeder herds grazing P-deficient pastures.

Survival analysis of germination data in response to temperature for Ornithopus species and other temperate pasture legumes.

Cool temperatures can limit productivity of temperate grazing systems as poor pasture growth rates in winter create feed shortages for livestock. Ornithopus spp. (serradella) are broadly adapted annual pasture legumes that produce high-quality forage in soil types considered marginal for other temperate legume species. However, serradella establishment is perceived to be difficult in cool-season environments. We used survival analysis to compare germination rate and seedling emergence for two serradella species (yellow serradella and French serradella) against three reference species (Medicago sativa, M. polymorpha and Trifolium subterraneum ) in four temperature treatments (10/5, 15/10, 20/15 and 25/20°C; max/min). We also compared shoot relative growth rate and photosynthetic rate at 15/10°C (cool) and 23/18°C (warm). Cool temperatures (10/5, 15/10°C) did not slow germination rates for serradella relative to the reference species, but warm temperatures (20/15, 25/20°C) delayed emergence and reduced post-emergent shoot growth rates. Once established, Ornithopus spp. had similar mean photosynthetic rates and stomatal conductance at cool temperatures to the reference species. We conclude that, contrary to common perception, cool temperatures did not adversely influence germination, emergence, or early growth of Ornithopus spp. relative to the reference species.

Impact of Droughts on Farms’ Financing Choices: Empirical Evidence from New Zealand

Abstract The interaction between climate change, agriculture, and financial markets is a topic that has been researched relatively little thus far. This paper intends to extend the literature by empirically testing the relationships between droughts and farms’ financing choices (measured in terms of real debt and equity) in New Zealand. Using microeconomic farm-level financial records available from the tax authorities, we quantify how past droughts (measured by the New Zealand pasture growth index) impact farms’ financing choices. We show a statistically significant positive impact of droughts on short-term and long-term debts, equity for dairy farms, and short-term debt for sheep and beef farms.

Modeling Pinus radiata D. Don growth and pasture production under different land uses and climate scenarios

Yield-SAFE is a biophysical model to predict long-term production according to light and water availability in agricultural, forest, and agroforestry systems. The Yield-SAFE model should be calibrated and validated for the highest number of tree species and crops to be used as a management tool that takes into account climate change. This study aimed to calibrate and validate the Yield-SAFE model for Pinus radiata D. Don and sown pasture (Dactylis glomerata L.) to estimate the production in (1) forest systems, (2) agricultural systems, and (3) silvopastoral systems established in Galicia (NW Spain) under different conditions of climate: (i) reference “current” climate from 1961 to 1990, (ii) climate from 2021 to 2050, and (iii) climate from 2051 to 2080. The Yield-SAFE model can now be used to assess the long-term productivity of P. radiata D. Don and D. glomerata L. under different land uses and climate conditions. The Yield-SAFE model simulated similar tree and pasture growth in all scenarios of climate because the inter-annual variation of climate was small. However, tree growth estimated with the Yield-SAFE model was higher in the silvopastoral systems than in the forest systems, indicating that land use had more impact on land productivity than climate. Therefore, in regions such as Galicia, the Yield-SAFE model could be used as a tool to support the land use change in an agroforestry context, whilst also including climate scenarios which is considered a valuable solution to mitigate the effect of climate change.

PERFORMANCE OF DAIRY COWS DURING DIFFERENT SEASONS WITH DAILY HERBAGE ALLOWANCE: A REVIEW

Pasture-based feeds are favored nowadays due to their cost-effectiveness and effect on animal welfare. Daily herbage allowance (DHA) affects the performance of dairy cows across different seasons. The key determinant of the performance of livestock is the dry matter intake (DMI) of herbage in pasture-based systems. A decline in average summer rainfall may result in considerably higher concentrate supplementation requirements to compensate for the loss in pasture growth and availability during autumn. Supplementation during autumn and winter boost total DMI and sustain milk output under grazing restrictions. Generally, milk production increases at high DHA but has no significant influence on milk fat content. In Spring, greater milk production lessens cows’ maintenance energy needs, and lower pasture content is linked to lower methane generation in the rumen. Methane generation declines in summer with increased digestibility at high intake levels. It is recommended to conduct an experiment exhibiting all seasons to eliminate factors that may affect the results across various studies. This review will understand variation in daily herbage intake of cows at pasture that allows the management of total intake to optimize milk production and identification of cows that are more efficient at converting feed into milk.

Assessment of conflicts between mangroves and human occupation in Subaé river outfall between the years 1988 to 2017

Coastal zones fulfill important ecological, social and economic functions. Because soil flooded by tidal variations and due to great variation in salinity. Mangroves cover these regions. They are also a tropical coastal ecological system, always in the lowlands, at the mouths of rivers and estuaries. Despite their important environmental role, mangrove areas have been continuously decreasing worldwide, with an average reduction of 30% in the last 30 years. Thus, this research sought to determine land use and land cover change in low Subaé. With emphasis on Mangrove areas and urban occupation. We used supervised classifications of satellite images to evaluate the changes. We chose images from 1988, 2003, and 2017. And used images from the Landsat series (30m) and an image from the PlanetScope satellite (3m). We validated classifications through the Tau and Geographical Simultaneity concordance measures. We observed that performing the spatio-temporal analysis observing only the variation of areas may not represent the phenomena that occurred. The overall Tau index calculation for the ratings was 0.89. During the period 1988-2017 there was a significant reduction in Agricultural areas, corresponding to around 15% of the study area. Meanwhile, growth of pasture from 24km² to 48Km² and the Urban Zone, occurred over all classes, including mangroves.

Effect of Sheep Grazing, Stocking Rates and Dolomitic Limestone Application on the Floristic Composition of a Permanent Dryland Pasture, in the Montado Agroforestry System of Southern Portugal.

Simple SummaryThe Montado is a characteristic ecosystem of the Mediterranean region, where agricultural activities, animal production and forestry coexist alongside tourism, hunting and leisure activities. Animal grazing is fundamental for the conservation of the Montado, and it is imperative to clearly understand its interactions with the pasture floristic composition (PFC) of the Montado. The objective of this study was to evaluate the effect of sheep grazing, stocking rates and dolomitic limestone application on the floristic composition of permanent dryland pastures, in the Montado agroforestry system of Southern Portugal. The type of grazing influences the PFC, which may be positively or negatively impacted, depending on the adopted system. Deferred grazing seems to benefit the disappearance of undesirable plants and the appearance of desired plants. The results of this study allow for more informed management decisions and a potential increase in animal production but also improve the knowledge of conservation strategies in the Montado.The Montado is a complex agroforestry–pastoral ecosystem due to the interactions between soil–pasture–trees–animals and climate. The typical Montado soil has an acidic pH and manganese toxicity, which affect the pasture’s productivity and pasture floristic composition (PFC). The PFC, on the other hand, can also be influenced by the type and intensity of grazing, which can lead to significant decreases in the amount of biomass produced and the biodiversity of species in the pasture. The objective of this study was to evaluate the effect of grazing type, by sheep, and different stocking rates on the PFC throughout the vegetative pasture cycle in areas with and without dolomitic limestone application. Thus, four treatments (P1UC to P4TC) were constituted: P1UC—without limestone application (U) and continuous grazing (CG); P2UD—U and deferred grazing (DG); P3TD—with the application of limestone (T) and DG; P4TC—T and CG. In DG plots, the placement and removal of the animals were carried out as a function of the average height of the pasture (placement—10 cm; removal—3 to 5 cm). The PFC was characterized in winter, at the peak of spring and in late spring. The PFC data were subjected to a multilevel pattern analysis (ISA). The combination of rainfall and temperature influenced the pasture growth rates and consequently the height of the pasture at different times of the year. Therefore, with the different growth rates of the pasture throughout the year, the sheep remain for different periods of time in the deferred grazing treatments. In the four treatments, 103 plant species were identified. The most representative botanical families in the four treatments were Asteraceae, Fabaceae and Poaceae. ISA identified 14 bioindicator species: eight for the winter period, three for the late spring vegetative period and three for the TC treatment.

Digestate Management and Processing Practices: A Review

The implementation of sustainable agro-energy systems that integrate crop, livestock, and bioenergy production is attracting increasing interest from farmers. Livestock produces large amounts of animal manure which can serve as organic fertilizer for crops and pasture growth. However, the nutrients contained in manure can adversely affect air, water, and soil quality and pose a public health risk if not handled properly. Existing manure management practices vary widely on a global scale. Researchers are striving to identify appropriate manure management practices with the aim of environmental protection. Anaerobic digestion of manure and subsequent digestate (DG) processing technologies have been proposed to stabilize manure so that it can be safely used for land applications. DG, which represents digested substrate removed from the anaerobic reactor after recovery of biogas, is a rich source of N, P, K, and S, various micronutrients, and organic matter, the addition of which to the soil can stimulate soil microbial biomass metabolic activities thus improving soil ecosystem function. However, the optimal fertilization properties of DG can be lost if it is neither fully stabilized nor contains biodegradable materials. To overcome these problems, various processing technologies can be used to convert DG into value-added by-products. Composting has been proposed as one such preferred post-treatment that can convert DG into mature, stable, safe, humus- and nutrient-rich compost. Other processing technologies such as thermal drying, gasification, hydrothermal carbonization, pyrolysis, membrane filtration, struvite precipitation, ammonia stripping, and evaporation have also been proposed for DG processing and nutrient recovery from DG. The objective of this review paper was to provide an overview of the current state of the art in DG management regulations and practices and to provide an update on the various processes that have been developed to meet DG stabilization requirements, with a focus on composting as one of the preferred solutions.

Modelling pasture management practices for soil organic carbon gain in livestock systems

AbstractOur ability to develop strategies to mitigate climate change includes an understanding of, and our capacity to predict soil organic carbon (SOC) dynamics in livestock systems. Here we assess the capability of the Sustainable Grazing System (SGS) Pasture Model for predicting pasture growth (elongated wheatgrass, Thinopyrum ponticum) and SOC accumulation in different environments and under a range of pasture management practices in hydrohalomorphic soils located in South‐eastern Buenos Aires Province, Argentina. After Model calibration, aerial net primary productivity (ANPP) and TSOC content under two grazing intensities (7.5 and 11 cm post‐grazing target heights) and two N fertilization levels (0 and 100 kg N ha−1 yr−1) were simulated over a 10 year‐period. The SGS Pasture Model predicted 87% of the observed ANPP, with observed and predicted ANPPs averaging 1.46 and 1.42 Mg ha−1 yr−1, respectively. There were differences in simulated ANPP between fertilized and unfertilized treatments both at high and low grazing intensities for the last year of the period. Total SOC contents from the modelling showed differences between high (83.7 to 84.2 Mg ha−1) and low (86.8 to 87.5 Mg ha−1) grazing intensities, with treatments receiving N also showing higher carbon stocks. The positive effect of reduced grazing intensity on soil carbon was explained by an increased input of aerial and subterranean dry matter into the soil. Sensitivity analysis showed that SGS is a robust model, capable of performing effectively under a variety of conditions. Hence, it can be used for exploring management practices to mitigate the impact of livestock systems on emissions and SOC stocks.

The Patitapu Soil Moisture Network (PTSMN) dataset and its deployment in New Zealand’s hill country

A significant portion of New Zealand’s beef and sheep pastoral farming systems are located in the East Coast hill country of the North Island. In these landscapes, one of the main drivers of pasture growth is the highly variable soil water content. Decision making about fertiliser applications, stock and feed budgeting are guided by pasture growth models which rely on soil water information. However, due to the difficulties related to conventional soil moisture data collection, soil water dynamics are still poorly understood in hill country. To capture spatial and temporal soil moisture variability on diverse terrain positions, a soil moisture monitoring network was established at the field scale. The Patitapu Soil Moisture Network (PTSMN) is composed of twenty multi-sensor probes, collecting data from four consecutive depths at 0.1 m intervals. The paper describes the PTSMN deployment and the strategic selection of sensor locations through an extensive spatial analysis and discusses the challenges associated with the network deployment in an operating hill country farm. Additionally, we demonstrate the non-normal nature of soil moisture distribution and that Year 1 and Year 2 showed similarly shaped density curves in the 0.2 − 0.4 m soil depths indicating temporal stability. Similar magnitudes of temporal stability suggested the PTMSN is a temporally stable network although stability changed with depth. Results indicated that soil moisture variability decreased with depth and that higher mean soil moisture content was associated with low variability. Descending and ascending transition stages, i.e., drying, and rewetting periods resulted in the highest spatial variability. As PTSMN is a member of the International Soil Moisture Network, the calibrated, quality checked 2-year dataset has been made accessible online. The presented soil moisture dataset is expected to contribute to the research of near-surface and root-zone soil water dynamics and to assist with the establishment of future networks.

THE IMPACT OF DROUGHT ON LIVESTOCK IN AFGOI, LOWER SHABELLE - SOMALIA

Drought is generally an extended period of months or years in which precipitation is less than the annual average and results in severe water scarcity. For the Horn of Africa region, drought occurrence has become increasingly severe during the last decade, with rainfall totals of at least 50–75 % below normal encountered in most areas, amounts that are not sufficient to support crop and pasture growth for livelihood security (Nicholson 2014). The main objective of this study was to evaluate and measure the impacts of the drought on stock market, milk, fodder, and meat productivity, along with the major effects on the pastoralist’s daily life. Methodology adopted in this research was quantitative approach include questionnaire and data analysis procedure, this study was employ through explanatory research design. The purpose affecting the variables involves in this study and helped to achieve all the objectives of research. The study was conducted from the livestock sales and pastoralists, afgoye district livestock market. The researcher had selected 80 respondent(s) randomly from the population. The data analyzed was performed using statistical package for social sciences (SPSS) version 16. Result, The study clarified the reason related to poverty caused by drought in various households 46.3%. As well as The study indicated that responders 56.3% was agreed to provided feed supplements for livestock during drought while 3.8% of responders not agreed. Also The study proven that the (55%) of responders said the Shortage of rainfall experienced towards the end of 2016 and early 2017 resulted in degradation of grazing veld, while (1.3%) of responders said not resulted in degradation of grazing veld. Conclusion, The survey results and field observations indicated that the afgoye livestock market was seriously affected by drought particularly in dry seasons. According to responder`s understand towards the period of drought time, the study indicated the majority of people lose their jobs, particularly in the livestock sector. Recommendation, the study recommended to all shepherds to establish an alternative project to store water and fodder to benefit from it during the long drought. , also the study recommended the government, NGO`s in dealing with disaster management in Somalia are currently focused on either emergency health preparedness or post emergency relief. There is need for them to shift their mindsets from reaction and charity to anticipation and preemption.

The Influence of Rotational Length, along with Pre- and Post-Grazing Measures on Nutritional Composition of Pasture during Winter and Spring on New Zealand Dairy Farms.

Simple SummaryInconsistencies in the quality (nutritional composition) of pasture herbage can potentially affect the lactational performance of dairy cows. The nutritional composition of ryegrass–white clover pastures was grazed at different rotation lengths in New Zealand, on the hypothesis that longer rotations lengths would result in more mature swards, with lower quality herbage. Grazing rotation length, leaf regrowth stage at grazing, and pre-grazing DM yield during winter and spring had significant effects on the pasture herbage quality. In New Zealand, the length of the grazing rotation is adjusted based on the pasture availability, seasonal variations, and growth rate of different pastures. This information can be helpful for dairy farmers to manipulate pasture management to optimise the cows’ performance.The quality of ryegrass–clover pasture was investigated between August (winter: start of calving) and November (spring: end of breeding) on pasture-based dairy farms (>85% of total feed from pasture) that had short (n = 2, Farms A and B; winter ~30 days, spring ~20–25 days) or long (n = 2, Farms C and D; winter ~35 days, spring ~25–30 days) grazing rotations to determine whether quality was affected by grazing rotation length (RT). Weekly assessments of pasture growth and herbage quality were made using a standardised electronic rising plate meter, and near-infrared spectroscopy, respectively. Data were subjected to repeated measure mixed model analysis, in which herbage quality was the outcome variable. The highest pre-grazing dry matter (PGDM) and height, post-grazing dry matter (DM) and height, and number of live leaves per tiller (leaf regrowth stage, LS) were present in late spring. Neutral detergent fibre (NDF), acid detergent fibre (ADF), metabolisable energy (ME), and organic matter digestibility (OMD) were positively correlated to each other (r2 ≥ 0.8) whilst ADF and lipid, and ADF and OMD were negatively correlated (r2 ≥ −0.8; p < 0.01). Metabolisable energy content was negatively correlated with ADF and NDF (r2 = −0.7, −0.8, respectively), and was inversely related to PGDM. Metabolisable energy was higher (p < 0.05) in farms with shorter (overall mean: 11.2 MJ/kg DM) than longer (10.9 MJ/kg DM) RT. Crude protein was also inversely related to PGDM and was higher with shorter (23.2% DM) than longer (18.3% DM; p < 0.05) RT. Pre-grazing DM affected the amount of pasture that was grazed and, hence, the amount of DM remaining after grazing (post-grazing DM or residual), so that PGDM was correlated with post-grazing height and residual DM (r2 = 0.88 and 0.51, respectively; both p < 0.001). In conclusion, RT, LS, and PGDM during winter and spring influenced the herbage quality, therefore, better management of pastures may enhance the productivity of dairy cows.

The Role of the Specific Properties of an Andosol as a Water Reservoir to Improve Pasture Growth and Prevent Soil Physical Degradation in Irrigated Grazing Systems

The Role of the Specific Properties of an Andosol as a Water Reservoir to Improve Pasture Growth and Prevent Soil Physical Degradation in Irrigated Grazing Systems

GrasProg: Pasture Model for Predicting Daily Pasture Growth in Intensive Grassland Production Systems in Northwest Europe

Knowledge about pasture growth rates is crucial for optimizing forage use efficiencies in intensively managed pasture and silage-based dairy systems, enabling optimized cutting/grazing times for high yields with high forage quality. The aim of this study was to parameterise a simple model, GrasProg, for predicting pasture growth in an intensively managed dairy production system under a cut-and-carry management. For this, pasture crop-growth rates were measured over a period of two years (2016 and 2017) at five contrasting sites in Schleswig-Holstein, Northern Germany. The pastures received nitrogen (N) fertilizer at a rate of 280 kg N ha−1 and were cut on a four-week interval. Average annual dry matter (DM) yields ranged from 10.9 to 11.6 t/ha for the three different locations. The DM accumulation simulated by GrasProg matched actual measurements over the varying intervals well (R2 = 0.65; RMSE = 49.5 g DM m−2; and NSE = 0.44). Two model parameters were adjusted within the vegetation period, namely, the relative growth rate, a proxy of the number of generative tillers, and the initial biomass at the start of each growth period, a proxy for the tillering density. Both predicted and measured pasture growth rates showed the same typical seasonal pattern, with high growth rates in spring, followed by decreasing growth rates to the end of the vegetation period. These good calibration statistics, with adjusting of only two model parameters, for the different sites and different climatic conditions mean that GrasProg can be used to identify optimum grazing or cutting strategies, with optimal yield and forage quality.

Modelling the effects of stocking rate, soil type, agroclimate location and nitrogen input on the grass DM yield and forage self-sufficiency of Irish grass-based dairy production systems

AbstractIn pasture-based dairy production systems, identifying the appropriate stocking rate (SR; cows/ha) based on the farm grass growth is a key strategic decision for driving the overall farm business. This paper investigates a number of scenarios examining the effects of SR (2–3 cows/ha (0.25 unit changes)), annual nitrogen (N) fertilizer application rates (0–300 kg N/ha (50 kg/ha unit changes)), soil type (heavy and a free-draining soil) and agroclimate location ((south and northeast of Ireland) across 16 years) on pasture growth and forage self-sufficiency using the pasture-based herd dynamic milk model merged with the Moorepark St Gilles grass growth model. The modelled outputs were grass growth, grass dry matter intake, silage harvested and offered, overall farm forage self-sufficiency and N surplus. The model outputs calculated that annual grass yield increased from 9436 kg DM/ha/year when 0 kg N/ha/year was applied to 14 996 kg DM/ha/year when 300 kg N/ha/year were applied, with an average N response of 18.4 kg DM/kg N applied (range of 9.9–27.7 kg DM/kg N applied). Systems stocked at 2.5 cows/ha and applying 250–300 kg N fertilizer/ha/year were self-sufficient for forage. As N input was reduced from 250 kg N/ha/year, farm forage self-sufficiency declined, as did farm N surplus. The results showed that a reduction in N fertilizer application of 50 kg/ha/year will require a reduction in an SR of 0.18 cows/ha to maintain self-sufficiency (R2 = 0.90).

Livestock exposure to bushfires and meat, offal and carcase quality: Is there an association?

The occurrence of bushfires (wildfires) is increasing with climate change in many areas of the world. In Australia, the 2019/20 bushfire season involved a particularly severe and widespread fire emergency (the ‘Black Summer’ bushfires). Understanding of how exposure to bushfires affects specific disease processes in livestock is limited. This research investigated spatiotemporal relationships between exposure to bushfires and observations of pneumonia and pleurisy in slaughtered sheep, and meat quality in slaughtered cattle. Two related cross-sectional studies were undertaken using historical abattoir monitoring data from the National Sheep Health Monitoring Project and the Meat Standards Australia Program. The study area involved the Australian states of New South Wales and Victoria, and the Australian Capital Territory, which were heavily affected by the ‘Black Summer’ bushfires. Carcase data were matched to fire occurrence data and to potential confounders including rainfall, pasture growth and pasture biomass indices for the farm of origin. The predictive approach to modelling included generalised additive mixed effects models and a generalised linear mixed model. Consistent though imprecise trends in pneumonia occurrence in sheep carcases were observed across time and distance since exposure to fire, with sheep slaughtered in the immediate aftermath of exposure to high intensity fires at a close distance having the highest occurrence (3.78 cases per 1000 sheep slaughtered 5 days after exposure to medium-to-high intensity fire at 0.5 km distance (95% CI 0.48, 30.02), compared to 0.387 cases per 1000 slaughtered sheep (95% CI 0.147, 1.02) across the study population). However, the economic implications of this for producers and processors are considered to be very limited. No such trends were observed in regards to pleurisy occurrence in sheep. Consistent trends were observed in meat quality in cattle carcases, with lower meat quality scores observed in cattle slaughtered after close proximity to fire (mean MSA index of 57.12 for cattle slaughtered 5 days after exposure to medium-to-high intensity fire at 0.5 km distance (95% CI 56.91, 57.34), compared to a mean of 57.65 (95% CI 57.60, 57.71) across the study population). In the aftermath of exposure to mid-to-high intensity fires, this may warrant consideration in withholding cattle from slaughter from an economic perspective, after decisions based on welfare grounds have been made. These observations will inform practical recommendations to improve health and productivity outcomes in management of bushfire-affected livestock. The observed trends may reflect causal relationships, but this requires further investigation with specific explanatory modelling studies.

Grassland Ecological Protection Monitoring and Management Application Based on ZigBee Wireless Sensor Network

Grassland plays a key role in human production and life, especially in the protection and improvement of the natural environment, which cannot be replaced by other ecosystems, such as maintaining water and soil, preventing wind and sand fixation, maintaining carbon balance, affecting climate change, and producing biological products,.. More importantly, contemporary society attaches great importance to the development of agriculture and animal husbandry. Protecting and nurturing grassland plants and animals, maintaining biodiversity, rational grazing, and maintaining the sustainable development of the grassland ecological environment have become the top priorities. In view of the current serious grassland degradation and the decline of livestock carrying capacity, this paper proposes a grassland environmental monitoring system based on the ZigBee wireless sensor network. The system consists of a grassland wireless monitoring network and a remote PC, which realizes real-time and remote monitoring of environmental information, such as air temperature and humidity, light intensity, and rainfall that affect the growth of grassland pastures. Based on the requirements of the agricultural field data monitoring system, the overall framework of the system was designed and built. The system mainly includes two parts: the ZigBee wireless sensor network subsystem and the remote management software subsystem, and data communication is realized between the two through the Ethernet system data exchange protocol. Among them, the ZigBee wireless sensor network subsystem is deployed in the grassland area and mainly realizes the functions of real-time collection, processing, and wireless transmission of grassland data. The remote management software subsystem is mainly used for data reception, storage, and display and can maintain communication with the gateway node to support real-time monitoring of grassland data by remote browsers.

APSIM‐Tropical Pasture model parameterization for simulating Marandu palisade grass growth and soil water in irrigated and rainfed cut‐and‐carry systems

AbstractProcess‐based models such as the Agricultural Production Systems Simulator (APSIM) can be useful to simulate pasture growth and development. This aim of the study is to parameterise the APSIM‐Tropical Pasture model to simulate Marandu palisade grass (Urochloa brizantha cv. Marandu), irrigated and rainfed, under cut‐and‐carry management. Parameterisation was performed with experimental data collected in Piracicaba, SP, Brazil (Experiment 1: 11 growth cycles), and São Carlos, SP, Brazil (Experiment 2: 9 growth cycles). In both experiments, aboveground live biomass, leaf, stem, crown and dead material mass, specific leaf area (SLA), leaf area index (LAI) and height were assessed. In Experiment 1, soil water content was measured with a capacitance probe, at depths from 0 to 0.9 m. Calibration was performed for base temperature, light extinction coefficient and radiation use efficiency. The calibrated model proved to be accurate in simulating living biomass, leaf mass, LAI and height for all tested variables. In the irrigated system, the statistics presented values between 0.64 and 0.86 for coefficient of determination (R2), between 0.59 and 0.70 for efficiency coefficient (NSE) and between 0.88 and 0.95 for the Willmott’s agreement index (d). For these same variables, in the rainfed system, R2 values ranged from 0.70 to 0.86; NSE from 0.54 to 0.70; and average d was 0.93. The simulation of soil water content showed satisfactory results for rainfed pasture, but was less precise for the irrigated treatment. The calibration of the APSIM‐Tropical Pasture model for Marandu palisade grass resulted in efficient simulations of pasture growth under cut‐and‐carry management.

Biological and economic responses to increasing nitrogen rates in Momba\xe7a guinea grass pastures

Nitrogen fertilization has been recognized as an essential tool towards the establishment of sustainable intensification of pasture-based livestock systems using tropical perennial grasses if, for a given ecosystem it is capable of increasing forage growth, stocking rates and animal performance. This study assessed pasture growth traits, nutritive value, animal and economic responses of Panicum maximum cv. Mombaça guinea grass pastures subjected to different levels of N fertilization (100 (N100), 200 (N200), and 300 (N300) kg N ha−1 yr−1). Pastures were managed under rotational stocking to maintain similar pre (80–90 cm) and post-grazing (45 cm) canopy heights. A partial budget and a Benefit–Cost Analysis were used to assess the economic returns on increasing N fertilization. N300 resulted in greater post-grazing herbage mass. A slightly higher neutral fiber and acid lignin detergent was observed at N100 (P < 0.05); crude protein increased linearly, and in vitro digestible organic matter reached maximum value at 265.4 kg N ha−1 yr−1. Annual averages of animal weight gain were 515, 590 and 660 g d−1, respectively, for N100, N200 and N300. There was a decrease from 3.7 to 1.9 kg of body weight gain per kg of additional N applied when increasing N rates from 100 to 200 and from 100 to 300 kg ha−1. The net profit improved with increasing N levels, but at reducing rates, reaching its maximum at the N300 level. The change from 100 to 200 kg N ha−1 presented the best return, with USD 3.73 for each additional dollar invested, while the change from 200 kg N ha−1 to 300 kg N ha−1 was economically less than optimal, recouping only USD 1.60 for each dollar. The N300 rate presented the highest net profit per hectare (accounting profit), even in a pessimist scenario (25% reduction in production). Despite being profitable, the N300 rate was less than optimal from an economic standpoint, since an additional 100 kg of Nitrogen ha−1 to change from N200 to N300 level reduced both the net returns and the Benefit–Cost ratio. Our results suggest that the economically optimal level of N fertilization for Mombaça guinea grass pasture should be between 200 and 300 kg ha−1.

Comparing a covered stand-off pad for on/off grazing during winter with conventional winter block grazing 2017-19 at DTT Stratford Demonstration farm

ABSTRACT&#x0D; A two-herd farmlet comparison was carried out on the DTT Stratford Demonstration Farm in Central Taranaki examined the profitability, environmental outcomes, animal welfare benefits and practicality of using a covered woodchip stand-off feed pad for wintering cows (Pad.) compared with wintering cows with no removal from pasture (Control). The two farmlets were set up and managed similarly in all aspects except that the non-lactating cows of one herd used the pad every night through the winter and over calving.&#x0D; Use of the covered pad limited winter pugging damage of pasture to minimal levels while the control farmlet had 6% of the area requiring rolling and some re-seeding. Pasture growth on these pugged areas was 24 to 30% lower than non-pugged areas over the spring to early summer period while estimated annual pasture growth was 2.2% higher on the Pad farmlet compared to the control over the two years. The mean difference in milksolids production across two years was 3%, (range :&lt;1%- 5%) in favour of the Pad herd. Nutrient losses calculated using OverseerFM calculated a 9% reduction in nitrogen leached from the use of the covered pad.&#x0D; A cost benefit analysis suggests that at best the use of the covered stand-off in winter covered the annual operating cost of the stand-off pad but failed to contribute to the capital cost of providing this facility.&#x0D; Keywords –Pasture growth, pasture pugging, milksolids production, profit, Labour input, nitrogen leaching