Effects of different coating agents on seed growth and planting of native grasses in alpine grassland

Simple SummaryThe degradation of high-altitude grasslands on the Tibetan Plateau threatens both the environment and local livelihoods. Insects play essential roles in keeping these ecosystems healthy, but it was unclear how different grassland restoration methods affect insect communities. Our study compared four approaches: grazing exclusion fencing, no-till reseeding, planting grass, and traditional grazing. We found that no-till reseeding supported the most diverse and balanced insect community, benefiting predators, plant-eaters, and decomposers alike. Grazing exclusion fencing helped plant-eating insects but was less effective for other groups, while planting grass even reduced the diversity of some important insects. Our results suggest that no-till reseeding is the most effective method to restore both insect diversity and overall grassland health. This approach can help the recovery of fragile ecosystems while supporting sustainable grazing practices.The severe degradation of alpine grasslands on the Qinghai–Tibet Plateau poses a significant threat to regional ecological security. While insects are critical for ecosystem functions, their responses to restoration measures in these fragile habitats are poorly documented. This study assessed the initial impacts of four restoration approaches—grazing exclusion fencing (FE), no-till reseeding (FR), planting grass (GC), and grazing control (CK)—on insect trophic guilds (herbivores, predators, saprophagous, and omnivores) in the Qilian Mountains. Using a multi-dimensional indicator (alpha, zeta, and dark diversity), we systematically assessed community assembly and recovery potential. The results revealed the following: (1) FE supported the highest insect abundance, dominated by phytophagous insects. FR significantly enhanced species’ richness and diversity across multiple functional groups (p < 0.05). GC significantly increased the richness of omnivorous insects, but caused a significant decrease in the Shannon–Wiener index for saprophagous insects (p < 0.05). (2) Zeta diversity revealed stable, widespread-species-dominated communities under FR and FE, while CK and GC favored rare-species-driven succession. Dark diversity analysis indicated high recovery potential for phytophagous insects under FR and FE, while GC enhanced saprophagous latent diversity. However, we emphasize that mechanistic interpretations require further validation. Our findings highlight no-till reseeding as a promising initial strategy, though longer-term studies are essential to evaluate successional trajectories and establish definitive management protocols for alpine grassland restoration.

Vegetation productivity is one of the most important indicators for grassland health, which is also an important parameters for calculating the livestock carrying capacity. This research on alpine grassland productivity changes in the source region of Yellow River helps us comprehend the dominating driven factors on alpine grassland degradation and improve decision making by the government managers, optimize their management practices, and increase grassland productivity and profitability. Aboveground green biomass (AGGB), livestock carrying capacity, land use / land cover change and climate change, etc. in 1980 were compared with that in 2005. Results indicated that the grassland conditions became worse, with lower aboveground palatable grass yield, plant height, and cover in 2005 compared with the results obtained in 1981. Average AGGB in 1980s was 3605.25 kg/ha which decreased to 2954.44 kg/ha in 2005, the decreasing rate was 18.1%, among which areas of higher productivity grassland decreased while areas of low to middle productivity grassland increased. At the same time, regional climate become warm and humid which was conducive to alpine grassland's recovery. In the meantime, however, although the actual livestock numbers decreased, they still exceeded the proper theoretical livestock carrying capacity, with and average overgrazing rate of 72.47%. Further investigations into the other impacting factors tells us that human activities were the main cause of alpine grassland degradation during the past 25 years.

Grasses and legumes are the two most significant plant species utilized as animal feed. Each of them has a special set of advantages that make it suitable for a distinct use. Thus, the objectives of this research work were to (i) evaluate the effects of planting density on growth and development of legumes and grasses, and (ii) examine the effects of planting density on the nutritional status of legumes and grasses for ruminant production. Five legumes and two grasses were subjected to 10 cm, 20 cm and 30 cm planting density in RCBD with three replications. ANOVA indicated that there were highly significant differences (P<0.001) in all the parameters measured. The plant density was also found to have highly significant (P<0.001) effect on internode and significant (P<0.05) effect on stem diameter and number of stems. Species by plant density interaction had highly significant effect (P<0.001) only on internode length. There was significant (P<0.05) decrease in morphological traits and biomass yields as the plant density increased. There were significant differences in mineral elements and proximate composition. Increase in plant density decreased the performance of plant species. The planting of both legumes and grasses at 30 cm spacing will be more beneficial for ruminant feed production.

강원도 대관령지역의 목초지에 발생하는 광엽잡초 중의 하나인 애기수영의 방제에 우수한 약제 이용을 위한 예비선발 결과 경엽처리 제초제는 MCPP 액제를, 토양처리 제초제로는 펜디유제를 선발하였다. 경엽처리제인 MCPP액제 처리시 방제효과는 500<TEX>$m\ell$</TEX>/10a를 처리시가 77.2%, 750<TEX>$m\ell$</TEX>/10a 처리시가 82.8%의 방제효과를 나타내었다. 그러나 지상부 고사로 형성된 나지를 통해 출아한 애기수영의 개체수가 무처리구에 비해 4배 이상이었다. 애기수영이 우점한 목초지에 펜디유제를 처리한 결과 애기수영의 rhizome의 생육억제에는 전혀 효과가 없었으나 초지를 전면 갱신한 후 펜디유제를 300<TEX>$m\ell$</TEX>/10a를 처리한 결과 83.0%의 애기수영 종자의 발아억제 효과를 나타내었다. 경엽처리제인 MCPP 액제와 토양처리제인 펜디유제를 연계처리시 MCPP 액제 500<TEX>$m\ell$</TEX>/10a와 750<TEX>$m\ell$</TEX>/10a의 농도로 먼저 처리한 처리구의 애기수영 방제효과가 각각 90.0%와 86.3%로 MCPP 액제를 나중 처리한 처리구의 66.7%와 78.3%보다 높았다. 지하부를 통해 재생하는 애기수영의 방제를 위해 MCPP 액제를 750<TEX>$m\ell$</TEX>/10a 농도로 20일 간격으로 2회 처리시 93.2%의 높은 방제가를 나타내었으며 목초의 수량도 높았다. 목초 중 MCPP 액제의 잔류량은 약제처리 20일째 500<TEX>$m\ell$</TEX>/ 10a 처리시 0.033ppm, 1000<TEX>$m\ell$</TEX>/10a 처리시 0.081 ppm을 나타내었으며, 펜디유제 잔류량은 약제처리 후 20일째 300<TEX>$m\ell$</TEX>/10a 처리시 0.07ppm, 600<TEX>$m\ell$</TEX>/10a 처리시 0.31ppm으로 두 약제 공히 잔류허용기준 0.5ppm 미만이었다. Red sorrel, as one of exotic weeds in Korea, was introduced along with imported cereals for concentrate feed or within the seed for forage production. The plant was dominated in grassland and reduced the quality of forage. In particular, this weed cause severe problem in alpine grassland. This study was carried out to investigate the effect and response of red sorrel and forage crops by foliar and soil applied herbicide application. Mecoprop(MCPP) and pendimethaline were selected by pre-field experiment trials and applied to control the red sorrel in grassland. Herbicidal activity of MCPP was 77.2% at 500<TEX>$m\ell$</TEX>/10a level and 82.8% at 750<TEX>$m\ell$</TEX>/10a level. However, seeds of red sorrel from bare land formed after foliar applied herbicide treatment were germinated and covered bare land. Pendimethalin was not reduced the rhizome growth grown from red sorrel root but retarded seedling growth of germinated red sorrel. The herbicidal activity of pendimethalin to the red sorrel seedling was 83.0%. 2 times application of MCPP at the rate of 750<TEX>$m\ell$</TEX>/10a was effective to control of red sorrel regrown from root and herbicidal activity was 93.2%. MCPP and pendimethaline treatment was not reduced growth of grass and have no herbicidal injury to forage crop seedling. Amount of MCPP and pendimethalin remained in grass plant was decreased from 20 days after herbicide treatment and could not be problem in livestock feeding.

Alpine grasslands on the Tibetan Plateau (TP) are highly vulnerable to various treatments and face significant degradation risks due to global environmental changes. However, the response of these grasslands to different external treatments remains uncertain, and the patterns behind functional group responses are unclear, impeding our ability to restore alpine grasslands under changing climate. To address this gap, we compiled a comprehensive database of 797 experimental observations of alpine grasslands in the TP, classified these communities into four common functional groups (e.g., grass and sedge), and conducted a meta-analysis to evaluate the response of aboveground biomass (AGB) to nine different treatments (e.g., grazing and nitrogen addition). Meta-regression was used to analyze the changes in AGB with treatment intensity and duration. We also used functional group asynchrony and unevenness to describe the complementary effects (CEs) and selection effects (SEs) of communities under these treatments. We found that among all the nine treatments, grazing had the biggest negative impact on the alpine grassland community by reducing AGB by 40.3%, mainly through decreasing the biomass of grass and sedge. Conversely, nitrogen and phosphorus addition had the largest positive effect, increasing AGB by 39.4% mainly by promoting the growth of grass. However, the increase in AGB was not significant in the interactive experiments involving grazing and nitrogen addition. The unevenness of the community decreased as grazing time prolongs, simplifying the structure of the community, with severe nutrient losses and weakened CE, while nitrogen addition could rapidly increase the AGB of grass and enhance the SE. CE or SE of communities can be enhanced through the restoration of specific functional groups, favoring the recovery of vegetation. Our study also revealed the potential of nitrogen compensation for repairing the damage caused by overgrazing on alpine grasslands.

Are land use and short time climate change effective on soil carbon compositions and their relationships with soil properties in alpine grassland ecosystems on Qinghai-Tibetan Plateau?

The alpine grasslands of the Kashmir Himalayas serve as a lifeline for the region’s pastoral communities, providing the primary source of forage for their livestock. These high-altitude rangelands are not only crucial for the livelihood of these communities but also play a significant role in maintaining the ecological balance of the area. However, sustainable pastoralism in these fragile ecosystem hinges on a thorough understanding of forage availability and livestock carrying capacity. This study assesses the forage dynamics and livestock carrying capacity of these high-altitude grasslands. Through comprehensive biomass sampling across 23 strategically selected sites, we calculated an average dry matter above ground biomass yield of 5.10 metric tons per hectare, resulting in a total dry biomass weight of approximately 820,489.22 metric tons (820,489,220 kg), over the entire grassland area of 160,974 ha. Using a daily forage intake of 1.3 kg per Sheep Unit (SU) over 50 grazing days, time period which corresponds to the renewal period for new grass growth, the average carrying capacity of the rangelands was determined to be 39.08 Animal Units (AU) per hectare and the total carrying capacity was estimated as 62,78,556 SU. The current stocking rate of 4,661,800 SU utilizes about 74.21% of this Carrying capacity, leaving a surplus of 25.77% or 1,616,756 Animal Sheep Units. However, localized overgrazing in areas such as Thajwas and Mohand Marg highlights the need for targeted management practices to prevent rangeland degradation. This data is critical as it provides a baseline for understanding the potential of these rangelands to support livestock. This study underscores the importance of sustainable livestock management to optimize carrying capacity while maintaining the ecological balance of the grasslands. Engaging local pastoral communities in these efforts is essential for the effective and sustainable management of the alpine grasslands in the Kashmir Himalayas.

The alpine grasslands on the Tibetan Plateau, which account for about 40% of the total grassland area in China, serve as an important ecological barrier to protect China’s water resources and for ecological security. Although the vegetation activity of alpine grasslands on the Tibetan Plateau has been overall improving during the past decades, most of the grasslands are still suffering from varying degrees of degradation, with some part even deteriorating. In the present protection and construction of ecological barriers on the Tibetan Plateau, the restoration of the degraded alpine grasslands through current technical approaches often end up with low stability and sustainability, and the ecosystem multifunctionality and multiserviceability of the grasslands are often difficult to be fully recovered. This is mainly because the present approaches rarely draw support from the natural restoration processes, along with the technical limitations of optimizing the assembly and supplementary sowing with appropriate native grass species that are often rare, and of improving soil quality using microbial fertilizer and nutrients. Therefore, it is urgent to develop an effective and sustainable restoration approach of the degraded alpine grasslands. The primary tasks of close-to-nature restoration with ecological conservation as its premise focuses on maintaining biodiversity and enhancing ecosystem multifunctionality and multiserviceability. Close-to-nature restoration adopts traditional artificial restoration approaches and relies on natural ecological processes to achieve sustainable ecological restoration. It focuses on “based on nature” and “return to nature”, and realizes sustainable restoration through the self-regulating function of natural ecosystem. Therefore, ecosystems that are restored through close-to-nature restoration may maintain higher biodiversity, provide more ecosystem functions and services, and increase resilience to natural disasters. This paper proposes to apply the close-to-nature restoration to recover degraded alpine grasslands on the Tibetan Plateau, and addresses why it is a natural choice on the basis of ecological theories with respect to biodiversity and the multi-functionality and multiserviceability of ecosystems, as well as the uniqueness of alpine grasslands on the Tibetan Plateau. Based on this, this paper further proposes that seed multiplication, and assembly and supplementary sowing technology of native grassland species are the bottlenecks to the close-to-nature restoration of alpine grasslands, and that the combination of soil nutrients and microbial regulation is an essential supplementary measure. This study, which integrates the theory of close-to-nature restoration and the corresponding techniques, hopefully can provide a nature-based solution for the restoration of the degraded alpine grassland ecosystems on the Tibetan Plateau.

The range of distribution of Chionochloa oreophila (snow patch grass), altitudinally and geographically, throughout the mountains of the South Island, New Zealand, is outlined. The floristic composition of 31 samples of C. oreophila ‐dominant vegetation indicates that the vegetation is fairly uniform, but there are regional differences. Few of the species present are confi!led to C. oreophila vegetation but many occur in open habitats of various kinds in the subnival and alpine zones and some others are distributed widely in alpine grasslands. Other vegetation samples show that C. oreophila plays a subordinate role and is uncommon or rare in alpine cushion vegetation which occurs in sites with extreme environmental conditions. It is only sparsely present, if at all, in closed alpine grasslands dominated by other Chionochloa species. C. oreophila occupies a narrow niche at the uppermost limits of closed alpine vegetation, between alpine grasslandli where taller grasses dominate, and subnival barrens, where frost‐heaving and other erosive processes prevent colonisation by a continuous plant cover. A late‐lying snow cover is important for the maintenance of C. oreophila stands, because it protects the sward from severe frost in autumn, winter, and spring, while inhibiting the growth of taller or more vigorous grasses.

Ecological agriculture expands in industrial countries. Therefore biological nitrogen fixation receives more attention. Especially grass species in mixed stands with legumes like alfalfa or clover play an important role for fodder production, because the dry mass and N yield of grass increase in comparison with grass pure stands. The N transfer between alfalfa and ryegrass under normal and enriched CO2 concentrations was studied through isotope dilution at a very low level of N fertilization (5,5 mg N/pot) in a pot experiment using quartz sand as substrate. The growth of grass and non nitrogen fixing alfalfa plants were limited and the N-transfer between alfalfa and ryegrass was only 0,06 kg N ha -1 at 360 ppm CO2 and 1,1 kg N ha-1 at 720 ppm CO2 although the nitrogen fixation was nearly constant. Root/ shoot ratio and root mass of ryegrass increased at 720 ppm CO2. We concluded that the improved root growth of grass plants promoted the uptake of fixed N from alfalfa plants. The duration of growth at 720 ppm CO2 until harvest was only two weeks and therefore mainly root exudates from alfalfa plants should be the source of increased fixed N in grass plants.

The term “invasive noxious weed species” (INWS), which refers to noxious weed plants that invade native alpine grasslands, has increasingly become an ecological and economic threat in the alpine grassland ecosystem of the Qinghai-Tibetan Plateau (QTP). Both the INWS and native grass species are small in physical size and share a habitat. Using remote sensing data to distinguish INWS from native alpine grass species remains a challenge. High spatial resolution hyperspectral imagery provides an alternative for addressing this problem. Here, we explored the use of unmanned aerial vehicle (UAV) hyperspectral imagery and deep learning methods with a small sample size for mapping the INWS in mixed alpine grasslands. To assess the method, UAV hyperspectral data with a very high spatial resolution of 2 cm were collected from the study site, and a novel convolutional neural network (CNN) model called 3D&2D-INWS-CNN was developed to take full advantage of the rich information provided by the imagery. The results indicate that the proposed 3D&2D-INWS-CNN model applied to the collected imagery for mapping INWS and native species with small ground truth training samples is robust and sufficient, with an overall classification accuracy exceeding 95% and a kappa value of 98.67%. The F1 score for each native species and INWS ranged from 92% to 99%. In conclusion, our results highlight the potential of using very high spatial resolution UAV hyperspectral data combined with a state-of-the-art deep learning model for INWS mapping even with small training samples in degraded alpine grassland ecosystems. Studies such as ours can aid the development of invasive species management practices and provide more data for decision-making in controlling the spread of invasive species in similar grassland ecosystems or, more widely, in terrestrial ecosystems.

The term "invasive noxious weed species&amp;#8221; (INWS), which refers to noxious weed plants that invade native alpine grasslands, has increasingly become an ecological and economic threat in the alpine grassland ecosystem of the Qinghai-Tibetan Plateau (QTP). Both the INWS and native grass species are small in physical size and share a habitat. Using remote sensing data to distinguish INWS from native alpine grass species remains a challenge. High spatial resolution hyperspectral imagery provides an alternative for addressing this problem. Here, we explored the use of unmanned aerial vehicle (UAV) hyperspectral imagery and deep learning methods with a small sample size for mapping the INWS in mixed alpine grasslands. To assess the method, UAV hyperspectral data with a very high spatial resolution of 2 cm were collected from the study site, and a novel convolutional neural network (CNN) model called 3D&amp;amp;2D-INWS-CNN was developed to take full advantage of the rich information provided by the imagery. The results indicate that the proposed 3D&amp;amp;2D-INWS-CNN model applied to the collected imagery for mapping INWS and native species with small ground truth training samples is robust and sufficient, with an overall classification accuracy exceeding 95% and a kappa value of 98.67%. The F1 score for each native species and INWS ranged from 92% to 99%. In conclusion, our results highlight the potential of using very high spatial resolution UAV hyperspectral data combined with a state-of-the-art deep learning model for INWS mapping even with small training samples in degraded alpine grassland ecosystems. Studies such as ours can aid the development of invasive species management practices and provide more data for decision-making in controlling the spread of invasive species in similar grassland ecosystems or, more widely, in terrestrial ecosystems.

Chemical restrictions, ecological concerns, liability issues, and public sentiment present challenges to land managers attempting to control highly invasive plants like Canada thistle (Cirsium arvense [L.] Scop.). Although herbicide application can be an effective control strategy, increasing limitations force managers of sensitive environments (e.g., national parks, wildlife refuges, protected water-bodies or waterways) to search for effective control alternatives. A greenhouse study was conducted to test the effectiveness of clipping (to simulate field mowing) and grass seeding as alternatives for Canada thistle control. Two native North American grasses (western wheatgrass [Pascopyrum smithii {Rydb.} A. L?ve] and streambank wheatgrass [Elymus lanceolatus {Scribn. & J.G. Sm.}Gould ssp. lanceolatus]) and one sterile hybrid cross between common wheat (Triticum aestivum L.) and tall wheatgrass (Thinopyrum ponticum [Podp.] Z.W. Liu & R.C. Wang) called RegreenTM were used. The effects of clipping and grass seeding on Canada thistle growth, and the effect of Canada thistle on grass growth, were evaluated using 14 unique treatments applied to potted Canada thistle and grass plants. Clipping inhibited Canada thistle growth (by 60%), while grass seeding had no effect. Presence of Canada thistle inhibited grass growth for all seeding treatments except when RegreenTM and western wheatgrass were seeded together with Canada thistle. Planting multiple species for restoration of Canada thistle-infested sites may be important (RegreenTM + western wheatgrass treatment), and cutting Canada thistle may be useful for reducing its growth in restored areas.

ABSTRACTDrought and elevated temperature often occur alone or in combination in many areas, limiting cool‐season grass growth. Rising atmospheric CO2 concentration may affect plant adaptation to drought and high temperature. The objective of this study was to investigate the effectiveness of elevated CO2 in mitigating the negative effects of drought or elevated temperature alone or a combination of these stresses on physiological processes in a perennial grass species. The effects of these treatments on water relations, photosynthesis, and respiration were determined in tall fescue (Festuca arundinacea Schreb. cultivar Rembrandt). Grass plants were subjected to the following treatments in growth chambers: heat stress (30°C or 5°C above the optimal level of 25°C), drought stress by maintaining soil water content at 50% of field capacity, or the combined two stresses for 28 d. Stressed and unstressed control plants were exposed to a constant level of either ambient CO2 (400 μL L−1) or elevated CO2 (800 μL L−1). At ambient CO2 concentration, drought and the combined stress for 28 d caused significant decline in leaf relative water content (RWC), photochemical efficiency (ratio of variable to maximum fluorescence [Fv:Fm]), net photosynthetic rate (A), stomatal conductance (gs), maximal ribulose‐1,5‐bisphosphate carboxylase oxygenase (Rubisco)‐limited rate of photosynthesis (Vcmax), and maximal electron transport‐limited rate of photosynthesis (Jmax) but increased membrane electrolyte leakage (EL) and dark respiration rate (Rd). Elevated temperature to 5°C above the optimal level resulted in the increases in gs, EL, and Rd but had no significant effects on the other physiological parameters. Drought stress for 28 d was more detrimental than increasing temperature by 5°C for tall fescue and the combined stress was more detrimental than either stress alone. Elevated CO2 mitigated the degree of change in all physiological factors under drought or heat stress and resulted in increases in A (162%) and RWC (19%) and a reduction in EL (21%) under the combined stress. These results suggest that elevated CO2 could improve tall fescue tolerance to drought and elevated temperature by enhancing plant water status, cellular membrane stability, and photosynthesis capacity and by suppressing gs for water loss and C consumption through lowering respiration rate.

Effect of the composition of planting media on the growth of pearl grass variagated (Axonopus Compresuss). Pearl grass variagated (Axonopus compresuss), is a kind of ornamental grass used as landscape grass or carpet grass. Planting pearl grass variegated at this time, just plowing land, only ultisol. These conditions cause the growth of slow grass, easy soil erosion, then it takes quite a long time to cover the land. Because Ultisol is poor for nutrients and has a solid soil structure, it requires a mixture of organic composition to add nutrients and improve soil structure to loose. Therefore Organic materials used such as sawdust and cow dung manure. The objective of the research is knowing the composition of planting media consists of, Ultisol (PMK), sawdust (SG) and cow‘s manure (KS) on planting of pearl grass variegated. Planting is done on the map with size 0.5 m x 0.5 m. This research used Completely Randomized Design () with 6 treatments, 5 replicates, each replication consist 25 plant and sampling 20%. Treatment for compositions such as m0 (PMK 100%), m1 (PMK 75%: SG 25%), m2 (PMK 75%: PS 25%), m3 (PMK 50%: SG50%), m4 (PMK 50%: PS 50%), m5 (PMK 50%, PS 25%, SG 25%). The research was done for approximately 3 months from mid August to November 2017 in experimental garden Faculty of Agriculture UNTAN. The Research shows that the composition of planting media have significant effect on observation variables, such as number of tillers, stolon length, cover area, root length and dry weight. The result of this research shows, the treatmen of m4(PMK 50% : PS 50%) has higher value among of other treatment.