Do roads lead to grassland degradation or restoration? A case study in Inner Mongolia, China

We use satellite remote sensing data of grassland cover in Inner Mongolia, China to test whether the existence of and the size of roads in 1995 is associated with the nature of the grassland in 2000 and/or if it affects the rate of change of the grassland between 1995 and 2000. The regression results show that the impact of roads on grassland cover depends on the nature of the resource. When the grassland is composed of relatively high quality grassland, roads lead to degradation, whereas when grassland resources are sparse, access to a road results in the restoration of the resource

Nitrogen management on large organic dairy farms

Large dairy herds need much grassland near the farm. Utilisation and losses of nitrogen in such grass-intensive crop rotations can be controlled by management: In grassland, grazing days or fertiliser input can be reduced, and following grassland cultivation, a barley whole crop for silage undersown with Italian ryegrass can reduce leaching to a minimum

Estimating vegetation cover from high-resolution satellite data to assess grassland degradation in the Georgian Caucasus

In the Georgian Caucasus, unregulated grazing has damaged grassland vegetation cover and caused erosion. Methods for monitoring and control of affected territories are urgently needed. Focusing on the high-montane and subalpine grasslands of the upper Aragvi Valley, we sampled grassland for soil, rock, and vegetation cover to test the applicability of a site-specific remote-sensing approach to observing grassland degradation. We used random-forest regression to separately estimate vegetation cover from 2 vegetation indices, the Normalized Difference Vegetation Index (NDVI) and the Modified Soil Adjusted Vegetation Index (MSAVI2), derived from multispectral WorldView-2 data (1.8 m). The good model fit of R2 = 0.79 indicates the great potential of a remote-sensing approach for the observation of grassland cover. We used the modeled relationship to produce a vegetation cover map, which showed large areas of grassland degradation

Organic grassland: the foundation stone of organic livestock farming

In organic farming, the components of the whole farm system interact closely and grassland plays the central role in this intricate web, including the arable cropping phase. Grassland is important particularly in relation to nitrogen supply via its influence on N-fixation, soil organic matter, structure and biological activity and it also has a major role to play in restricting the build-up of arable weeds and soil-borne crop diseases in arable rotations. Ruminant livestock share this central role with grassland on most successful organic farms, and the success of the livestock enterprise is intimately tied up with the management and productivity of the grassland

Grassland carbon sequestration and emissions following cultivation in a mixed crop rotation

Grasslands are potential carbon sinks to reduce unprecedented increase in atmospheric CO2. Effect of age (1 to 4-yr-old) and management (slurry, grazing multispecies mixture) of a grass phase mixed crop rotation on carbon sequestration and emissions upon cultivation was compared with 17-yr-old grassland and a pea field as reference. Aboveground and root biomass were determined and soils were incubated to study CO2 emissions after soil disturbance. Aboveground biomass was highest in 1-yr-old grassland with slurry application and lowest in 4-yr-old grassland without slurry application. Root biomass was highest in 4-yr-old grassland, but all 1 to 4-yr-old grasslands were in between the pea field (0.81±0.094 g kg-1 soil) and the 17-yr-old grassland (3.17±0.22 g kg-1 soil). Grazed grasslands had significantly higher root biomass than cut grasslands. There was no significant difference in the CO2 emissions within 1 to 4-yr-old grasslands. Only the 17-yr-old grassland showed markedly higher CO2 emissions (4.9 ± 1.1 g CO2 kg-1 soil). Differences in aboveground and root biomass did not affect CO2 emissions, and slurry application did not either. The substantial increase in root biomass with age but indifference in CO2 emissions across the age and management in temporary grasslands, thus, indicates potential for long-term sequestration of soil C

Some environmental aspects of grassland cultivation; the effects of ploughing depth, grassland age, and nitrogen demand of subsequent crops

The Netherlands has submitted a derogation under the Nitrate Directives to the European Union (EU) in 2000. In the final opinion by a group of experts about the Dutch derogation, recommendations on ploughing of grasslands were included dealing with i) the depth of ploughing of permanent grassland, ii) the age of temporary grassland and iii) the nitrogen demand of the subsequent crop of temporary grassland. A literature study was carried out in order to provide scientific information on these three issues. No studies were found in literature in which the effects of cultivation depth on nitrogen mineralisation and losses in reseeded grassland were assessed. The results of transformation of grassland into arable land show no clear effects of ploughing depth on N mineralisation. Differences in nitrogen mineralisation after 5 and 3 years temporary grassland are small. Italian and perennial ryegrass, potato, silage maize, winter wheat, and several vegetables have a high nitrogen demand (i.e. >250 kg N ha-1)

Historical Grassland Turboveg Database Project. 2067 Relevés recorded by Dr Austin O’ Sullivan 1962 – 1982

User Guide and CD of Database are availableEnd of project reportThe more common grassland types occupy about 70% of the Irish landscape (O’Sullivan, 1982), but information on these vegetation types is rare. Generally, Irish grasslands are distinguished based on the intensity of their management (improved or semi-natural grasslands), and the drainage conditions and acidity of the soil (dry or wet, calcareous or acidic grassland types) (Fossitt, 2000). However, little is known about their floristic composition and the changes in floristic composition over time. The current knowledge on grassland vegetation is mostly based on a survey of Irish grasslands by Dr. Austin O’Sullivan completed in the 1960’s and 1970’s (O’Sullivan, 1982). In this survey O’Sullivan identified Irish grassland types in accordance with the classification of continental European grasslands based on the principles of the School of Phytosociology. O’Sullivan distinguished five main grassland types introducing agricultural criteria as well as floristic criteria into grassland classification (O’Sullivan, 1982). In 1978, O’Sullivan made an attempt at mapping Ireland’s vegetation types including the five grassland types distinguished in his later publication as well as two types of peatland vegetation (Figures 1 and 2). This map was completed using 1960’s soils maps (National Soil Survey, Teagasc, Johnstown Castle) and a subsample of the dataset on the composition of Irish grasslands. Phytosociological classification of vegetation is based on the full floristic composition of the vegetation as determined by assessing the abundance and spatial structure of the plant species in a given area. The actual area of the survey (or relevé) is determined according to strict criteria, which include how representative the sample area is for the wider vegetation (i.e. how many of the species found in the wider area are also present in the survey area).National Parks and Wildlife Service of the Department of the Environment, Heritage and Local Government, Dublin, Ireland

Productivity and forage quality of a phytodiverse semi-natural grassland under various management regimes

Grassland management experiment (GrassMan) was set up in 2008 on a permanent semi-natural grassland in the Solling uplands, Germany. The main research focus is on the ecosystem functioning of the phytodiverse grassland (e.g. productivity and forage quality, water and nutrient fluxes). The aim of our study was to analyse the effects of vegetation composition and functional diversity on productivity and forage quality of the semi-natural permanent grassland. Variation in sward composition was achieved by herbicide application and resulted in three sward types: control sward type (without herbicide application), monocot-reduced and dicot-reduced. Further management factors included different nutrient input levels (without fertilizer and 180-30-100 kg/ha of N-P-K per year) and use intensity (cut once or three times a year). Functional diversity was determined by estimation of the yield shares for each species in the species composition and their specific functional characteristics. Forage quality was analysed by near infrared spectroscopy (NIRS). While sward type influenced the forage quality, yield variation was explained mainly by the management regime

Nitrate leaching and spring wheat bread making quality following cultivation of grasslands of different composition, age and management

The influence of sward botanical composition and ley age on grassland residual effects, quality of spring wheat and subsequent nitrate leaching was investigated. Grazed grasslands of different age (1, 2 and 8 production years) and composition (unfertilised grass-clover and fertilised perennial ryegrass) were ploughed and followed by spring wheat and spring barley. For reference, an adjacent field without grassland history but with the same crop sequence in 2002-2003 was treated with increasing quantities of N fertiliser. Yields and N uptake of spring wheat following grasslands always exceeded those of the reference plots with a history of cereal production. The nitrogen fertiliser replacement values of grass-clover and ryegrass were 59-100 and 72-121 kg ha-1, respectively, with the highest values representing the 8-year-old leys. Grain yield and N uptake increased while those for straw decreased with increasing ley age. There were no effects of previous grassland type (grass-clover/ryegrass) on content of protein, starch and gluten, but grassland age significantly influenced protein (P<0.05) and gluten (P<0.01) contents. It is suggested that N mineralisation following the ploughing of older grass leys occurred later than when following the 1st year ley. The protein and gluten contents of wheat following unfertilised grass-clover corresponded to those following cereals given 125-150 kg N ha-1, but the rheological properties of the gluten were different to what could be achieved using equivalent quantities of mineral fertiliser. Probably, the slow release of N from decomposition of old grassland gave a better synchrony between N release and plant demand. Nitrate leaching in year 1 after ploughing was significantly influenced by type of grassland (P<0.001) with 10 and 29 kg N ha-1 leached from grass-clover and ryegrass, respectively. Nitrate leaching following ploughing of 1-year-old leys averaged 11 kg N ha-1 which was significantly lower than the 24 kg N ha-1 following 2 or 8-year-old leys. The flow-weighted mean nitrate concentration decreased from 8.5 mg N l-1 in year 1 after grassland cultivation to 4.5 mg N l-1 in year 2. More N was released following ploughing of ryegrass swards and from grasslands of increasing age, but differences were moderate compared to the estimated N-surplus. This indicates that when organic matter in grasslands is partially decomposed and readily mineralisable N used, the remaining organic N is released only very slowly