Proximal Sensing in Grasslands and Pastures

Abstract

Reliable measures of biomass, species composition, nitrogen status, and nutritive value provide important indicators of the status of pastures and rangelands, allowing managers to make informed decisions. Traditional methods of sample collection necessitate significant investments in time and labor. Proximal sensing technologies have the potential to collect more data with a smaller investment in time and labor. However, methods and protocols for conducting pasture assessments with proximal sensors are still in development, equipment and software vary considerably, and the accuracy and utility of these assessments differ between methods and sites. This review summarizes the methods currently being developed to assess pastures and rangelands worldwide and discusses these emerging technologies in the context of diffusion of innovation theory.

Floristic Composition: Dynamic Biodiversity Indicator of Tree Canopy Effect on Dryland and Improved Mediterranean Pastures

“…Reliable measures of biomass, composition of plant communities and nutritive value are critical to assessing the ecological health of a landscape and provide important indicators of the status of pastures, allowing managers to make informed decisions [11]. Pasture growth rates vary due to abiotic (soil, climate, elevation, among others) and biotic conditions (pasture genetic potential, soil microbiology, grazing management, among others) which together highlight the need for regular paddock-level pasture cover assessment [32].…”

“…Nonetheless, these dryland pastures have low productivity [6], as they predominantly occupy poor and acid Cambisols and are subject to a marked seasonal and inter-annual variability of temperature and, especially, of the distribution of precipitation along the productive seasons (autumn, winter and spring), followed by summer drought stress [9]. The recommended procedure to adequately manage and to increase the productivity of these extensive production systems is based on soil fertility amendment through chemical fertilizer applications [10], which requires a good understanding of the effect of factors such as tree canopy, fertilization and soil amendment on the pasture growth, allowing managers to make informed decisions [11].…”

“…This is required in order to maintain high nutritive value in grasslands [8] and, in essence, constitute the source of animal food, but, at the same time, there are vulnerable hotspots in terms of biodiversity [13]. Biodiversity can be viewed as a dynamic bio-indicator of the long-term evolution and conservation of the capacity of this ecosystem to provide valuable services [11,13], functioning under future environmental scenarios [12]. "Indicator species analysis" (ISA) are good diagnostic tools to simplify and understand observed species patterns [21], to identify potential risk of invasive plants' expansion [13] or ecological niches of species with relatively narrow habitat and microclimatic requirements [21].…”

Real-Time Quantification of Crude Protein and Neutral Detergent Fibre in Pastures under Montado Ecosystem Using the Portable NIR Spectrometer

“…Actually, the use of proximal sensors is already a reality and should increase, with the reduction of sensor costs and complexity [52]. Due to the low cost, speed and reliability attributed to the NIR technique to estimate the quality of pastures, it is predictable that its adoption in the future will be great, providing more timely information to assist the farmers in their decision making [11,28].…”

“…It is expected that this adoption will mainly involve the use of a portable spectrometer, since it implies less processing time, less labour and real-time results. For the use of these technologies by farmers to be a reality, it is necessary to carry out research in the context of a real farm, in order to identify the advantages and barriers to adoption by agricultural managers [52]. As was the case in the Pullanagari et al [28] study, the present study also focused on the evaluation of a micro-NIR sensor-a sensor never before used in pastures in the Montado ecosystem-in the prediction of CP and NDF in real farms.…”