Physical Sciences and Mathematics Commons^™

How Do Plants Respond To Grazing At A Molecular Level?, Gongshe Liu, Xin Huang, Shuangyan Chen

IGC Proceedings (1993-2023)

Grazing is a multiple-component process that includes wounding, defoliation, and saliva depositing. The molecular mechanism for how plants respond to grazing in grassland is a new topic. To address this question, we performed gene expression activities within 2 to 24 hours of grazing and proteomics analysis of rice seedling, examining hundreds of genes and proteins. Some key genes in GeneChips analysis specifically researched were β-amylase, LcSUT1, LcDREB3, and FEH gene. BSA (bovine serum albumin), an important and abundant component in saliva was used to study the saliva-plant interaction in grazing. Combined with corresponding gene and grazing research by …

Faecal Near Infrared Spectroscopy To Measure The Diet Selected And Productivity Of Grazing Ruminants, Rob Dixon, Maryline Boval, Vincent Blanfort, Virginie Decruyenaere, David Coates

IGC Proceedings (1993-2023)

In ruminants near infrared spectroscopy of faeces (F.NIRS) can measure the concentrations of faecal constituents such as N and fibre. It can also directly estimate many diet attributes, including total N, fibre, digestibility and the major plant groups (e.g. monocots versus dicots, and some plant species). In some situations F.NIRS can be used to estimate voluntary intake and liveweight change, but it is difficult to encompass animal effects (e.g. lactation, maturity), pasture availability or mineral deficiencies. Application of F.NIRS, especially in conjunction with other measurements (e.g. metabolizable energy intake calculated from liveweight change, ^{13 …}

Can Grazing Behaviour Support Innovations In Grassland Management?, Paulo C. De F. Carvalho

IGC Proceedings (1993-2023)

Grazing is a fundamental process affecting grassland ecosystem dynamics and functioning. Its behavioural components comprise how animals search for feed, and gather and process plant tissues in different spatio-temporal scales of the grazing process. Nowadays, there is an increasing emphasis on grazing management and the role of the grazing animal on ecosystem services, concomitantly with a decreasing emphasis on grazing management generating animal production outputs. Grazing behaviour incorporates both approaches, which are not necessarily dichotomist. It would help in order to support innovation in grazing systems. However, it is unclear how the significant knowledge, developed in this research area since …

Local Consequence Of Global Process: Challenges Of Maintaining Pastoral Production In High Mountain Pastures Of Nepal, Lila Nath Sharma

IGC Proceedings (1993-2023)

Grassland pastures are important livelihood resources for local people in agro-pastoral production in high mountainous areas of Nepal. The character of these pastures, as part of cultural landscape, result from historical interaction of human activities and local ecological processes. Fire and grazing are two important landscape drivers that have a direct impact on the structure, diversity and composition of pastures. Recently, grasslands in many semi-arid regions of world are undergoing rapid transformation as consequence of changes in fire and grazing regimes. One conspicuous change is an abrupt proliferation of native shrub species. Migration of herders away from marginal mountain areas …

Linking Farmer Knowledge And Biophysical Data To Evaluate Actions For Land Degradation Mitigation In Savanna Rangelands Of The Molopo, South Africa, Christiaan J. Harmse, Niels Dreber, Klaus Kellner, Taryn M. Kong

IGC Proceedings (1993-2023)

The over-utilization of semi-arid savanna rangelands in the North-West Province of South Africa has resulted in profound habitat transformations. A common regional indicator of rangeland deterioration is the imbalance in the grass:woody ratio characterized by a loss of grass cover with increased shrub or tree density. This can result in profound reductions of rangeland productivity forcing farmers to apply active or passive actions to improve rangeland condition to mitigate economic losses. This study forms part of the multinational EU-project PRACTICE (Prevention and Restoration Actions to Combat Desertification: An Integrated Assessment) and aims to evaluate locally applied restoration and management actions …

Some Pasture Changes In The Eastern Steppe Of Mongolia, Dorjgotov Ariungerel, Ts Ouyntsetseg

IGC Proceedings (1993-2023)

Significant vegetation changes have been recorded in Mongolian steppe types such as Speargrass-Cleistogenes, Cleistogenes-Forbs and Filifolim sibiricum-Speargrass and these changes have been attributed to climate factors rather than human activity. Species dominance in those pasture types exhibited change that was linearly related to the degradation ratio. For example, Speargrass, which is a dominant species in the steppe and is seen as a preferred species for building sustainable grasslands, is slowly losing dominance in the eastern steppe grassland type due to heavy degradation and is replaced by a range of sedges. During the years of this study …

Role Of Fires, Herbicides And Fertilizer In Manipulating Shrub/Grass Balance In Mediterranean Grasslands, Zalmen Henkin

IGC Proceedings (1993-2023)

The decline of traditional pastoral systems has highlighted the problem of managing shrub encroachment in shrublands of the Mediterranean region, especially in marginal habitats. Ephemeral grasslands appear after fire in Mediterranean shrub communities on phosphorus-deficient soils, but natural successional processes rapidly led to their dominance. In a study, aimed at reducing the rate of successional change and extending the period of grassland dominance, phosphorus was applied after fire to improve herbaceous growth and two years later the regenerating Sarcopoterium spinosum shrubs were controlled with selective herbicide. Subsequently, the vegetation in the treated areas was monitored for more than 20 consecutive …

Role Of Competition In Restoring Resource Poor Arid Systems Dominated By Invasive Grasses, S. Mangla, R. L. Sheley, J. J. James, S. R. Radosevich

IGC Proceedings (1993-2023)

An understanding of competition intensity and importance may be a useful step in helping managers understands how to prioritize restoration efforts in resource poor environments within the semi-arid steppe. The aims of this study were to quantify the intensity of competition among invasive annual grasses and native perennial bunchgrasses, and determine the importance of competition in explaining variation in target plant biomass and survivorship in a Wyoming big sagebrush steppe community type in southeastern Oregon, USA. Addition series experiments were conducted in 2008 and 2009 among four species. Treatments consisted of monoculture densities of each species to assess intraspecific competition, …

The Changing Patterns In Grasslands And Soil Fertility Along The Eastern Eurasian Steppe Transect Across China–Mongolia–Russia, Xiangyang Hou, Leonid Ubugunov, S. Tserendash, Haijun Chen, Wenjun Han, Xiangjun Yun, Ding Yong, Wang Zhen, Lei Ji

IGC Proceedings (1993-2023)

This paper analyses the adaptation and change in species along the north-south Eastern Eurasian Steppe Transect across China – Mongolia – Russia and considers the implications for climate change and management. The plant community diversity, above-ground biomass, N:P ratios of community and of dominant species, soil N (nitrogen), soil P (phosphorus) and AP (available phosphorus) contents were studied along a 1400 km north-south transect. The main findings were: (1) the community diversity and productivity decreased with the increase in latitude and a significant negative correlation was found between the many plant characteristics and latitude (P < 0.05) – decreasing diversity, biomass and N:P ratios; (2) soil AP content was lowest in Inner Mongolia, whereas no significant change in soil total P with latitude was found in China-Mongolia-Russia transect, a significant positive correlation was detected between the soil nutrient (N and AP) and latitude (P < 0.05); (3) a significant positive correlation was evident between plant community P content and soil AP content (P < 0.01), but a negative correlation was found between community N:P ratio and soil AP content (P < 0.05). The soil AP content can be used as a soil properties indicator to reflect the plant communities P content and N: P ratio. It is suggested that greater human activities in Inner Mongolia may be an important factor affecting soil AP content, community N:P and plant growth.

Agroecosystem Health Cards: A Practical Tool For Sustainable Management Of Grasslands, Iker Mijangos, Isabel Albizu, Mikel Anza, Iker Martin, Sorkunde Mendarte, Lur Epelde, Carlos Garbisu

IGC Proceedings (1993-2023)

The traditional grazing activity carried out for centuries in mountainous areas of the Basque Country (Northern Atlantic Spain) facilitated the presence of different extensive pasture habitats, such as those included in the Gorbeia Natural Park and surrounding valleys (43° 02’N, 2° 49’W). Currently, these pastures are highly valued due to the ecosystem services they provide. In this context, one of the main objectives of the LIFE-SOILMONTANA project (ref. LIFE 10 NAT/ES/579) is to develop a practical tool that allows grassland managers (farmers, scientists and authorities) to auto-evaluate the suitability of alternative agronomic practices in relation to the conservation of these …

Drought Monitoring And Evaluating For Qinghai-Tibet Plateau Grassland, Shuan Qian

IGC Proceedings (1993-2023)

The grassland is the main part of the Qinghai-Tibet Plateau which consists of 30% of grassland in China. The method of grassland drought monitoring and evaluating was studied on base of Penman-Monteith equation (Allen et al. 1998) and AVIM-GRASS model (Qian et al. 2012 ) using daily meteorological data in Qinghai-Tibet Plateau from 1961 to 2007. Temperature, precipitation, sunshine hours, evapotranspiration, water surplus and deficit of a year and four seasons, in the growing season from April to September were systemically calculated and analysed. The grassland drought index was developed according to climate suitability of grassland vegetation, water …

Vegetation Survey Undertaken Using Automatically Located Photographs During Horse Trek In The Dachigam National Park, India, Aya Nishiwaki, Nobumi Hasegawa, Rikako Kimura

IGC Proceedings (1993-2023)

An efficient way is needed to undertake large scale monitoring of grassland vegetation. Satellite images or aero-photographs are very useful for this purpose, but extensive ground truth data are required to make accurate analysis and interpretation. However, obtaining large-scale information from detailed vegetation surveys by manually deter-mining species composition is difficult and costly. As an alternative to traditional land-based methods, we used a GPS digital camera that determines locations automatically and captures pictures for vegetation survey. Our testing was done in the Dachigam National Park where grassland has been heavily grazed by goat, sheep, and cattle (Hasegawa et al, …

The Development Of A Grazing Rating Index To Identify The Biomass Removed And The Plant Species And Parts Eaten By Grazing Sheep, Felicity Cox, Warwick B. Badgery, David R. Kemp, Gaye L. Krebs

IGC Proceedings (1993-2023)

Determining the diet selection of grazing animals is inherently difficult and a trade-off exists between obtaining accurate information and interfering with the normal grazing behaviour of an animal. The botanical composition of a grazing animal’s diet may be estimated using one or a number of techniques in combination. A six-point grazing rating index was developed to identify the plant species consumed by sheep grazing within a heterogeneous native grassland and the extent to which each species within a quadrat was grazed. The method was developed to remove error from visual estimates that prevents detection of significant reductions in biomass for …

Behaviour Of Grazing Goats On Tanzania Grassland Under Different Residue Leaf Area Index In Southeastern Brazil, Ana C. Ruggieri, Nailson L. S. Lemos, Victor C. Silva, Naomi C. Meister, Fernando O. Alari

IGC Proceedings (1993-2023)

Defoliation intensity is important for grassland management. While the residue is the result of defoliation, maintaining a remaining leaf area is essential, as leaf area index (LAI) determines forage yield, by increasing percentage of light interception and incident light capture. The understanding of animal behavior is also essential for adopting strategic measures to manage grasslands since the behavioral factor is the link between plant and animal performance. The objective of this study was to evaluate changes of the behavioral characteristics of goats grazing on Tanzania grassland (Panicum maximum cv. Tanzania) under rotational stocking with different residue leaf area index …

Sward Management Targets In Natural Grasslands Of Southern Brazil, Carolina Bremm, Jean C. Mezzalira, Lidiane Fonseca, Carlos A. O. Oliveira, Emilio A. Laca, Carolina S. Silva, Luis H. S. Correia, Paulo C. De F. Carvalho

IGC Proceedings (1993-2023)

The relationship between environment, plant and animal is one of the most important focuses in the ecological and productive context of natural grasslands. The limited knowledge of the complexity of this environment can lead to inappropriate management strategies, determining degradation, biodiversity and productivity losses. This study is based on the concept that the best way to conserve natural grasslands is through adequate management targets.

This study aimed to identify sward management targets that maximize productivity in natural grasslands of Southern Brazil.

The Dilemma Of Using Sward Height As A Management Tool For Intensively Grazed Sheep Pasture In Spring, David R. Stevens, Andrew J. Wall, Bryan R. Thompson, Karren T. O’Neill, Ian C. Scott

IGC Proceedings (1993-2023)

Sward height is often used as a tool for both animal and pasture management, especially when continuously grazing pasture. For example, sward height has been used to define the conditions for optimal feed intake of multiple-bearing ewes, both before and after lambing (Everett-Hincks et al.2005; Morris and Kenyon 2004). Sward height is easily applied by the grazier and so becomes an effective tool. However, changes in the leaf distribution and relative species makeup of the sward both seasonally (Thomson et al. 2001) and in response to grazing management (Webby and Pengelly 1986) mean that the amount of pasture per unit …

Differences In Species Composition Of The Soil Seed Banks Among Degraded Patches In An Agro-Pastoral Transition Zone In Inner Mongolian Steppe, Gaowen Yang, Nan Liu, Hanshu Zhou, Yingjun Zhang

IGC Proceedings (1993-2023)

Degraded grasslands were distributed in patches characterized by fringed sagebrush (Artemisia frigida), narrowleaf stellera (Stellera chamaejasme), shining speargrass (Achnatherum splendens), or white swordflag (Iris lactea) at an agro-pastoral transition zone of the south Inner Mongolian steppe, which have been retrogressive from a Leymus chinensis steppe. A control patch (undegraded) was located close to the four degraded patches. We investigated the size, composition, species richness of soil seed banks, and its relation to the aboveground vegetation. The density of soil seed banks was highest in the white swordflag patch, intermediate in the shining …

A Technique To Evaluate Rangeland Health, N. Barakanova, B. Kirychuk

IGC Proceedings (1993-2023)

According to pasture law in Kyrgistan, pasture management is executed by local communities. The aim of Community Pasture Management Plans is to decrease risks of reducing pasture quality and to raise pasture resource use sustainability. One of the important parts of a pasture management plan is pasture health assessment. The objective of our work was to develop a rapid and simple technique to assess pasture health for community members and other land managers who live or work on pastures. This tool is the result of a collaborative effort of scientists from different countries. This technique utilizes 6 indicators, which are …

Using Participatory Research, Remote Sensing And Field Surveys To Build A State And Transition Model For The Native Pastures Of Northern Uruguay, Marcelo Pereira Machín

IGC Proceedings (1993-2023)

Native grasslands cover 55% of the agricultural lands of Uruguay. Balancing conservation, agricultural production and human well-being is a major management challenge. Adaptive management approaches have been developed for leased land, underpinned by a newly developed state and transition model (STM). The model was tested in northern Uruguay, in the Department of Paysandú, covering an area of 8300 ha. Floristic surveys were used to define five states, based on the relative cover of key plant species and functional types. Each state was characterized in terms of livestock density, sheep/cattle ratio and years since last ploughing. Aboveground Net Primary Production (ANPP) …

Toward A Method Of Collaborative, Evidence-Based Response To Desertification, Brandon T. Bestelmeyer, Joel R. Brown, Jason W. Karl, Jeffrey E. Herrick, Kris M. Havstad

IGC Proceedings (1993-2023)

Over generalized narratives about how desertified ecosystems will respond to restoration actions may result in wasted resources, missed opportunities, or accelerated degradation. Evidence-based collaborative adaptive management (CAM) could solve this problem by providing site-specific information that is trusted by users and enables learning opportunities. Although calls for CAM are increasing, many recommendations remain abstract and difficult to operationalize in specific projects. We review some general challenges for managing desertification in rangelands and draw upon recommendations in the recent literature to develop a 6-step method of CAM to address desertification. The method draws upon our ongoing experiences and makes novel connections …

Does The Short-Term Grazing Affect Functional Group And Plant Species Diversity Of Alpine Meadow In The Tibetan Plateau?, Fuhong Miao, Zhenggang Guo, Yuying Shen

IGC Proceedings (1993-2023)

Grazing affects the physiological and ecological characteristics of the plant community, through livestock intake and trampling (Georgiadis et al. 1989). Previous studies in the Qinghai-Tibetan Plateau have shown that the composition and structure of alpine meadow plant communities respond to grazing (Niu et al. 2010). However, the changes to functional groups and species diversity caused by grazing are not well documented, especially with regards to short term effects (McLaren 2008). In this study, different grazing rates were used to determine the relationship between functional groups, community diversity and yak stocking rates. The objective of this study was to …

Morphological Acclimatation And Canopy Structure Characteristics Of Arachis Pintoi Under Reduced Light And At Full Sun, Raquel S. Barro, João C. Saibro, Alexandre C. Varella, Igor J. Carassai, Carlos Nabinger, Gilles Lemaire

IGC Proceedings (1993-2023)

The canopy structure is a key variable to determine the adaptive potential of forages and it influences the radiation use efficiency (RUE) under different light conditions. The light extinction coefficient calculated from the Beer-Lambert formula (k) shows the canopy architecture and light interception patterns of plants and thus their potential ability to convert light energy (photosynthetically active radiation-PAR) into plant biomass (Hirose 2005). Under shade, forages may experience changes in plant morphology and canopy structure. Many authors reported those changes and relate them to modifications in light quantity and quality (Varella et al. 2010). The magnitude of these morphological …

Morphogenetic And Structural Characteristics Of Clones Of Elephant Grass Managed Under Intermittent Stocking, Carlos Augusto Brandão De Carvalho, Priscila Beligoli Fernandes, Domingos S. C. Paciullo, Carlos A. M. Gomide

IGC Proceedings (1993-2023)

Morphogenetic studies of the growth dynamics of leaves and tillers of forage grasses have enabled the management strategies for grasses to be defined for various environmental conditions (Euclides et al. 2010). As the development of clones of Pennisetum purpureum is recent (Pereira e Lédo 2008), detailed information on their growth characteristic under pasture is necessary as a reference for the adoption of appropriate management practices. The objective of this study was to assess the morphogenetic and structural characteristics of basal and aerial tillers in pastures of two small-size clones of elephant grass managed under intermittent stocking for six grazing …

Canopy Height And Its Relationship With Leaf Area Index And Light Interception Of Tropical Grasses, Janerson José Coêlho, José C. B. Dubeux Jr., Erick Rodrigo Da Silva Santos, João Manoel Carneiro Leão Neto, Márcio V. Da Cunha, Mércia V. F. Dos Santos, Alexandre C. L. De Mello, Mário De A. Lira

IGC Proceedings (1993-2023)

Photosynthetic tissues, mainly green leaves, are the major component of forage growth and development. The amount of these tissues in a forage plant is influenced directly by the cutting management, which is based on cutting frequency and stubble height. It is usual to recommend as a management practice to cut (or graze) the forage whenever it reaches a given stubble height. Brougham (1956) stated that, when the forage canopy is intercepting 95% of the photosynthetic active radiation, this is the critical leaf area index (LAI), which means the forage is near its maximum growth rate without shading itself. There is …

Threshold Dynamics Of Vegetation And Their Management Implications In A Mongolian Shrubland, Takehiro Sasaki, Asuka Koyama, Toshiya Okuro

IGC Proceedings (1993-2023)

The concept of ecological threshold has spurred important advances in understanding the nonlinear behavior of ecosystems to various disturbances (Groffman et al. 2006, Suding and Hobbs 2009). Studies on lakes, coral reefs, and arid grasslands have shown that structural attributes of ecosystems can change abruptly along a disturbance gradient (Scheffer and Carpenter 2003, Mumby et al. 2007, Sasaki et al. 2008). Yet, such nonlinear response patterns are implicitly assumed to reflect the modification of system feedbacks and interactions. We know little about mechanistic linkages between nonlinear response patterns and underlying feedback mechanisms, and the irreversibility of nonlinear …

Leaf Epidermal Descriptors Of Forage From Caatinga, Ne Brazil, Mércia V. F. Dos Santos, Osniel F. De Oliveira, Márcio V. Da Cunha, José C. B. Dubeux Jr., Alexandre C. L. De Mello, Joelma Da S. Souza, Mário De A. Lira

IGC Proceedings (1993-2023)

In the Brazilian semi-arid region, the predominant vegetation is the Caatinga, which has a diversity of plant species, some endemic and presenting forage potential. The characterization of the plant anatomy is important for animal diet studies, using a microhistological technique (Scott and Dahl 1980) for estimating the diet botanical composition from ruminant faeces. This paper determined leaf epidermal descriptors for Caatinga species using microscopic slides.

Effects Of Livestock Grazing Intensity On Reproductive Changes In Festuca Ovina L., Somaye Alidoost, Masoume Amirkhani, Mousa Akbarlou, Mansour Mesdaghi

IGC Proceedings (1993-2023)

Reproduction and re-generation strategies, whether by sexual or asexual means, are important attributes of grazed plants. The Gramineae family is the main element of rangelands, grasslands and grassland ecosystems by virtue of their seed production and distribution mechanisms, and their tolerance of environment stresses (cold, heat, drought). Festuca ovina is a highly palatable and productive plant that has been recommended for drilling and sowing in the steppe and semi-steppe rangelands of Iran. The aim of this study, which was located in the Ghorkhoud region in North-east Iran, was to investigate the effects of different grazing intensities on reproduction of this …

Persistence Of Red Clover (Trifolium Pratense L.): Relationships Between Plant Population And Forage Yield, Fernando Ortega, Andrés Quiroz, Leonardo Parra, Juan Levío, Muriel Melo

IGC Proceedings (1993-2023)

Red clover (Trifolium pratense L.) is an important forage species in temperate regions of the world; in Chile, it is a valuable resource for animal production and for the seed industry. However, the main limitation of this species worldwide is the lack of persistence related to the high mortality of plants due to a complex of multiple biotic and abiotic factors (Ortega 1996; Taylor and Quesenberry 1996). Therefore, in 1989, a red clover breeding program was started at INIA Carillanca Research Center, Chile, with the main objectives of improving the survival of plants, forage yield and persistence. Since then, …

Temporal Variations In The Carbon And Nitrogen Ecological Stoichiometry Of Lucerne, Zhennan Wang, Huimin Yang, Yuying Shen

IGC Proceedings (1993-2023)

Ecological stoichiometry has been of great help in research investigating the coupling between plant and environment (Sterner and Elser 2002). It provides some synchronized evidence to explain the response and adaptability of plants to the environment. Carbon and nitrogen ecological stoichiometry (C/N) also embraces the use efficiency of nitrogen in plants. Previous research has focused on the spatial responses of plant C/N to different environmental factors (Yang and Wang 2011). However, there is still insufficient attention on the temporal variation in C/N, in the hope that such effort will help elucidate the mechanisms underlying plant growth/regrowth. Lucerne (Medicago sativa …

Changes In The Content And Allocation Of Carbon And Nitrogen During Forage Regrowth, Huimin Yang, Zhennan Wang, Xiaoyan Zhang

IGC Proceedings (1993-2023)

Regrowth after cutting or grazing perennial grasslands sustains the production potential of forage and the persistence of grassland species. The changes in nature, content and allocation of compounds within plant parts are fundamentally correlated to the forage regrowth process (Lambers et al. 2008). These compounds are sourced from reserves and new assimilates. Carbohydrates and proteins stored mainly in the stem base and the root play an important role at the early stages of regrowth (Meuriot et al. 2004). The newly assimilated compounds include carbon from photosynthesis for the residual leaf and stem, and nitrogen absorbed by the roots …