Catch and Cover Crop Biomass Bioconversion into Energy: Comparison
View Latest Version
Please note this is a comparison between Version 2 by Camila Xu and Version 1 by Małgorzata Pawłowska.

Catch and cover crops are defined as crops sown in pure or mixed sowings between two main crops. A short vegetation period is a key feature of these plants.

  • cover crops
  • catch crops
  • biomass
  • renewable energy sources
  • climate neutrality

1. Characteristics and Spatial Distribution of Catch and Cover Crops

Catch and cover crops are defined as crops sown in pure or mixed sowings between two main crops [23][1]. A short vegetation period is a key feature of these plants [24][2]. Depending on the sowing date, one can distinguish stubble catch crops sown after harvesting the main crop at the end of summer and harvested or ploughed in the fall of the same year or left in the field until spring; winter crops sown after harvest at the end of summer and harvested in the spring of the following year; and undersowing catch crops, plants that tolerate shade well, which are sown together with the main crop and after harvesting and left in the field until autumn [25][3]. The biomass of these plants is used in various ways on farms. It can be used for forage purposes—directly grazed (forage) or processed to fodder in a form of hay or silage; introduced into the soil to improve its chemical properties and its structure (soil improver), for example, as a source of nutrients and organic matter after direct ploughing; or left in the field as a form of mulch after previous mowing or damage by frost. It can also play a protective role in relation to the soil surface, preventing water or wind erosion, or protect nitrogen resources in the soil by incorporating it and retaining it in the biomass in the period after the harvest of the main crop plants [26,27,28][4][5][6]. The latter function is fulfilled by plants with increased nitrogen fixation efficiency (expressed in a low C:N ratio) belonging to the Fabaceae family, such as peas, lupins, seradela, vetch, clover, alfalfa). Through the symbiosis with nitrogen-fixing bacteria growing inside the root nodule cells of these plants, atmospheric nitrogen becomes available to plants and may be incorporated into their biomass [29,30][7][8]. Thanks to the production of specific root secretions, many CCC plants have a phytosanitary effect, which involves stimulating the development of beneficial soil microflora and microfauna and limiting the development of pathogens and pests [17,31,32][9][10][11]. In addition, introducing additional plant species, especially mixtures, between the main crops increases biodiversity.
In agricultural practice, many plants are in use that, when grown between the main crops, improve the properties of the soil and contribute to increasing its fertility and yields. Table 1 summarizes the types of plants used as CCCs in the world that are most frequently mentioned in the literature.
Table 1. Typical plants cultivated as cover or catch crops in different parts of the world, and their additional applications (main sources [33,34][12][13]).
Family Species Application/Function Distribution References with Regard to Use as CCC
Asteraceae

(alt. Compositae)		 Niger, Niger seed

(Guizotia abyssinica)		 Soil improver, fodder; source of oil Africa: Ethiopia (n)

Africa (cult., natur.)

Asia (cult. natur.) Australia (cult.) South. Europe (natur.)		 [35,36,37][14][15][16]
Sunflower

(Helianthus annuus L.)		 Fodder; honey production, oil production, ornamental, human food, North. America (n)

Widely cult.		 [36][15]
Boraginaceae Lacy phacelia, purple tansy

(Phacelia tanacetifolia Benth.)		 Soil improver: cover crops; honey production; ornamental function; phyto sanitary function North America (n) Australia (natur.)

Europe (natur.)		 [36,1537,][1638,][1739,]40,41][[18][19][20]
Brassicaceae

(alt. Cruciferae)		 White mustard

(Sinapis alba)		 Soil improver (deep root system): cover crops; fodder; source of lipids; medicine herbs; phytosanitary function Europe

North. Africa

West. Asia		 [39,40,42,43,44][18][19][21][22][23]
Fodder radish, Oilseed radish

(Raphanus sativus)		 Soil improver (deep and bulky root system), cover crop; fodder; phytosanitary function Widely cult. [37,39,45][16][18][24]
Camelina, false flax

(Camelina sativa L.)		 Soil improver: cover crop, green manure, source of oil; fodder Asia (n)

Europe (n),

North America (n) Widely natur.		 [35][14]
Turnip, field mustard, colbaga

(Brassica rapa L.)		 Soil improver: cover crop, human food; fodder Widely cult. [39,45][18][24]
Rape, rapeseed, winter canola

(Brassica napus L.)		 Soil improver: cover crop; fodder Widely cult. [45,46][24][25]
Fabaceae (alt. Leguminosae) Cowpea, field pea

(Vigna unguiculata L. Walp)		 Soil improver: green manure, cover crop; catch crop; forage; human food Africa (n)

Widely cult.		 [47,48][26][27]
Sunn hemp, Indian hemp

(Crotalaria juncea L.)		 Soil improver: green manure, cover crop; forage; catch crop, nitrogen-fixing, fiber production Asia (n)

South Africa

Cult. throughout tropics		 [47,49][26][28]
Yellow lupine

(Lupinus luteus L.)		 Soil improver: cover and catch crops; fodder; forage;

medicine herbs		 North. Africa (n)

South. Europe (n)

Australia (cult.)

West. Asia (natur.)

South. Africa (natur.)		 [50,51][29][30]
Narrowleaf lupin, narrow-leaved lupin, blue lupin

(Lupinus angustifolius)		 Soil improver: catch crop; fodder; forage North. Africa (n)

West. Asia (n)

South. Europe (n)

Australia (cult.)		 [52][31]
White lupine (Lupinus albus L.) Soil improver; cover crop; fodder; forage; ornamental function Asia (n)

Europe (n)

Widely cult.		 [53][32]
Alfalfa, lucerne (Medicago sativa L.) Soil improver, cover crop, fodder Africa (n)

Asia (n)

Europa (n)

Widely cult.		 [54,55,56][33][34][35]
Common vetch

(Vicia sativa L.)		 Soil improver: catch crop; fodder; forage Africa (n)

Asia (n)

Europe (n)

Widely cult.		 [35,36,37,44,57,58][14][15][16][23][36][37]
Fodder vetch, hairy vetch, winter vetch (Vicia villosa Roth.) Soil improver: catch crop; fodder; forage (but can be toxic to horses) Africa (n)

Asia (n)

Europe (n)

Widely cult.		 [39,59,60][18][38][39]
Faba bean, fava bean, broad bean

(Vicia faba L.)		 Soil improver: catch crop, cover crop Widely cult. [39,50,58][18][29][37]
Seradela, French serradella

(Ornithopus sativus Brot.)		 Soil improver: catch crop; forage North. Africa (n)

South. Europe (n)

Australia (cult.)

Europa (cult.)

Africa (natur.)		  
Egyptian clover, berseem clove

(Trifolium alexandrinum L.)		 Soil improver: catch crop; forage Africa (cult.)

Asia (cult.)

Australia (cult.)

Europa (cult.)

Northern America (cult.)		 [39,58][18][37]
Reversed clover, Persian clover

(Trifolium resupinatum L.)		 Soil improver: catch crop; forage; fodder Africa (n)

Asia (n)

Europa (n)

Widely cult.		 [61][40]
White clover

(Trifolium repens L.)		 Soil improver: catch crop; forage; Africa (n)

Asia (n)

Europa (n)

Widely cult. in temperate regions		 [44][23]
Red clover

(Trifolium pratense L)		 Soil improver: catch crop; forage; fodder; honey production, food additive Africa (n)

Asia (n)

Europa (n)

Widely cult. and natur. in temperate regions		 [43,46,56,62][22][25][35][41]
Crimson clover

(Trifolium incarnatum)		 Soil improver: catch crop; forage; fodder; honey production Africa (n)

Asia (n)

Europa (n)

Widely cult. in temperate regions		 [50,52,62][29][31][41]
Pea, field pea

(diverse Pisum sativum L.)		 Soil improver: catch crop; human food Africa (n)

Asia (n)

Europa (n)

Worldwide (cult.)		 [36,46,52,58,60][15][25][31][37][39]
Poaceae (alt. Gramineae) Black oat, lopsided oat, bristle oat

(Avena strigose)		 Soil improver: cover crop, green manure; forage; fodder;

source of oil used in cosmetics		 Europe (n)

South America (cult.)

South. part of North America (cult.)

South Africa (cult.)		 [35,37,47][14][16][26]
Common oat

(Avena sativa L.)		 Soil improver: cover crop; human food; fodder; forage Widely cult. [46,47,56,60][25][26][35][39]
Rye, common rye, winter rye, stooling rye (Secale cereale) Soil improver: cover crop, green manure,

human food; forage; fodder		 Asia (n)

Europa (n)

Widely cult.		 [39,47,52][18][26][31]
Triticale (Triticale A. Müntzing) Soil improver: cover crop, green manure; forage, human food Europe (cult.)

Asia (cult.)

South Africa (cult.)		 [47,56][26][35]
Italian millet, foxtail millet

(Setaria italica L.)		 Forage, fodder, cover, green manure South. Asia (n)

Asia (cult.)

Africa (cult.)

South. Part of North America (cult.or natur.)		 [47,60][26][39]
Finger millet

(Eleusine coracana L. Gaertn.)		 Cover, human food, fodder Asia (cult.)

South Africa (cult)		 [47,49][26][28]
Pearl millet, bajra

(Pennisetum glaucum)		 Soil improver: cover crops, erosion control; forage; fodder; human food; ornamental Asia (cult.)

Africa (cult.)

North America (cult.)		 [47,49,58,63][26][28][37][42]
Japanese millet, white millet

(Echinochloa esculenta)		 Soil improver: cover crop; fodder; forage; human food Africa (cult.)

Asia (cult.)

North America (cult.)

South America (cult.)		 [63][42]
Westerwold ryegrass, Italian ryegrass (Lolium multiflorum Lam.) Soil improver: cover crop, erosion control; fodder; forage Africa (n)

Asia (n)

Europa (n)

North. America (natur.)		 [62,64,65,66][41][43][44][45]
Perennial ryegrass, English ryegrass (Lolium perenne L.) Soil improver: cover crop, erosion control; fodder; forage Africa (n)

Asia (n)

Europa (n)

North, America (natur.)

South. America (natur.)

Australasia (natur.)		 [62,66,67][41][45][46]
Meadow fescue, English bluegrass (Festuca pratensis Huds.) Soil improver: cover crop, erosion, forage Africa (n)

Asia (n)

Europa (n)

Widely natur.		 [66][45]
Orchard grass, cocksfoot

(Dactylis glomerata L.)		 Soil improver: cover crop; fodder; forage; ornamental Africa (n)

Asia (n)

Europa (n)

North. America (cult.)

Australasia (natur.)

South. America (natur.)		 [54,62][33][41]
Polygonaceae Common buckwheat

(Fagopyrum esculentum Moench)		 Soil improver: cover crops, green manure; human food; forage; fodder; honey production Asia (n)

Widely cult. and natur.		 [35,37,39,59][14][16][18][38]
Abbreviations: n—native, cult.—cultivated, natur.—naturalized.
Looking at the information given in Table 1, many of the plants used as cover or catch crops, for example, common vetch, hairy vetch, common oat and common buckwheat, are cultivated in various regions of the world, while some, due to unique habitat requirements, are used only in specific regions. The latter include plants, for example, pearl millet, Japanese millet, finger millet, Italian millet, niger and sunn hemp, that grow in the tropical or subtropical zone. The most numerously represented families of plants from the CCC group are Fabaceae (alt. Leguminosae) and Poaceae (alt. Gramineae).
Cover crops are cultivated in monocultures or in mixtures. According to the literature review given by [21][47], the five highest yielding monoculture cover crops in humid temperate regions are sorghum, sunn hemp, millet, rye and annual ryegrass, while in semiarid regions these are cowpea, barley, triticale, oat and rye. Some research has shown that crop mixtures can be superior compared to pure stands in terms of their aboveground biomass yield and nutrient catching due to their higher durability under unfavorable conditions [68,69,70][48][49][50]. Additionally, Heuermann et al. [71][51] observed higher belowground biomass yield in the case of more diversified mixtures compared to the simpler ones. They examined four plant species, different in terms of root morphology: white mustard (Sinapis alba), lacy phacelia (Phacelia tanacetifolia), bristle oat (Avena strigosa) and Egyptian clover (Trifolium alexandrinum), which were grown both in pure stands and in a mixture. As the results of research conducted by other scientists indicate, mixed crops do not always have a clear advantage over monocultures in terms of yield [72][52]. Florence and McGuire [73][53] conducted a review of the literature, which showed that over 80% of researchers who compared cultivations of monocultures and mixtures did not find a significant difference between the compared biomass parameters. It can therefore be assumed that the beneficial effect of the species mixture is determined by additional factors, perhaps the appropriate selection of species, for example, in terms of the diversity of the root system, which is indicated by the research conducted by [71][51].
The composition of the mixtures is selected depending on the habitat conditions, and type and function of the crop. For example, in regions with a temperate climate, winter cover crops often used are mixtures, like: hairy vetch and crimson clover; hairy vetch and rye; hairy vetch and triticale; and crimson clover and rye [74[54][55][56],75,76], and in a dry climate, one can use mixtures of cowpea, foxtail millet and sunflower as well as mixtures of various combinations of plants such as: millet, triticale, red clover and fodder radish [77,78][57][58].
The wide variety of plant species that are adapted to different habitat conditions allows the most favorable CCC species for a given climatic and soil zone to be found. However, particular plant species differ in terms of biomass composition, which can influence their suitability for energy production, especially via biochemical processes.

2. Features of Catch and Cover Crops (CCCs) Biomass Important Because of Biochemical Conversion into Biofuels

Biomass of catch and cover crops (CCCs), similarly to the other types of biomass, can be used as a source of energy after conversion into biofuels, such as biomethane, alcohol, bio-oil and biohydrogen (via biochemical, chemical or thermochemical processes) or directly after combustion. The application of appropriate bifunctional catalytic materials (e.g., Bronsted–Lewis acid), which allow biofuels and chemicals to be produced from lignocellulosic biomass, offer the great opportunities [79][59]. The choice of the method for converting biomass into energy depends largely on the dry matter content of the raw material. Biological methods, such as methane fermentation, can be used when the moisture content of the feedstock allows intensive development of microorganisms and is not less than 60% dry weight (d.w.) (in the case of dry anaerobic digestion systems) or over 85% (in the case of wet anaerobic digestion systems). However, direct combustion of biomass is justified when the moisture is low, e.g., for straw it is recommended that it is not higher than 25% [80][60]. Thermochemical methods are instead recommended for dry biomass. When biomass is converted by widely known processes such as pyrolysis (under anoxygenic conditions) or gasification (under oxygen-deficient conditions), the water content should be in the range of 10–20% d.w. in the case of gasification [81][61], and 15–35% d.w. in the case of pyrolysis [82][62]. However, a high moisture content does not exclude the possibility of using biomass for the production of biofuels in thermochemical processes. Hydrothermal conversion processes such as hydrothermal liquefaction (HTL), hydrothermal carbonization (HTC) and hydrothermal gasification HTG (supercritical water gasification) allow the conversion of wet biomass into biofuels, such as bio-crude oil, hydrochar and a mixture of combustible gases, respectively. These processes are carried out at temperatures of 100–700 °C and high pressures of 5–40 MPa in a liquid media or hot supercritical water [83][63]. However, technologies based on these processes are not yet widely used at a technical scale. Thus, in the case of wet biomass biological methods, such as anaerobic digestion, are still preferable. Additionally, well-known technology and the possibility of it using in on a small scale, e.g., on large agricultural farms, are an important arguments for the use of these methods.
The water content of the raw biomass of CCCs varies significantly depending on many factors, among them, plant species and growth stage. Research conducted on corn by [84][64] in a Mediterranean climate showed that the highest dry matter content, approx. 54% of d.w., was observed in the phase of maturity, while the dry matter content in biomass harvested at the end of the vegetative stage was about 15%. According to the study of Piskier [85][65], the content of total solids in the corn straw was still high and varied between 40 and 55%. A significant increase in dry matter content from 26.1 to 38.5% d.w. between the early dent and black layer stages of corn growth was observed by Rabelo et al. [86][66]. Changes in dry matter content in phacelia (Phacelia tanacetifolia) biomass between pre-flowering and end-flowering phases ranged from 32.6 to 54.6% d.w. [87][67]. Tekeli et al. [88][68] found that the dry matter content in Persian clovers increased from 6.8 to 12.2% d.w. between the stages of pre-bud and full-bloom.
The results of these studies show that the raw biomass of CCC plants is characterized by high water content even in the later stages of development, such as full-bloom, which indicates its greater suitability for being processed into biofuels using biological methods. If one chooses such methods, there is no need to remove water. Therefore, preparing biomass is less energy-intensive and expensive than preparing it for processing in thermochemical processes, such as pyrolysis and gasification, which require preliminary partial dewatering [89][69].
However, when choosing biochemical methods, an important feature of biomass is its high biodegradability, which determines the high efficiency of the conversion of chemical energy contained in organic compounds into useful forms of energy. Biodegradability depends on the chemical composition of organic matter, which in turn depends on such factors as the plant species, part of plant, growth stage, harvest time, climate conditions, soil properties and fertilization. Biomass with a high content of non-structural and water-soluble carbohydrates, as well as a low content of lignin, is highly biodegradable [90,91][70][71]. Microorganisms can degrade the labile fraction of organic substrates, avoid resistant molecules (e.g., lignin) and produce stabilized metabolites [92,93][72][73]. A high lignin content not only reduces biogas production due to difficult biodegradability of this compound, but also due to the reduction in the hydrolysis of cellulose by creating a physical barrier for cellulases and reducing their availability because of the sorption of these enzymes on lignin [94][74]. As shown in the data presented in Table 2, the lignin content in the raw biomass of plants used as cover crops ranges from 1.42 to 20% d.w., which shows its significantly different biodegradability. Chaves et al. [95][75] examined grass and legume and found that lignin content in perennial ryegrass (Lolium perenne) varied from 2.38 to 4.35%, while in white clover (Trifolium repens), red clover (Trifolium pratense) and lucerne (Medicago sativa), it was 5.87, 6.23 and 6.12% d.w., respectively.
The chemical composition of biomass varies significantly depending on the stage of plant growth. A decrease in the content of crude protein was observed in phacelia biomass between the pre-flowering and end-flowering phases, from 19.8 to 14.8% d.w., and crude fat, from 2.8 to 1.4% d.w. At the same time an increase in the contents of acid detergent fiber (ADF) and neutral detergent fiber (NFD) was observed, from 28.6 to 32.3% d.w. and 39.0 to 45.0% d.w., respectively [87][67]. Tekeli et al. [88][68] stated that the content of crude protein in Persian clovers between the stages of pre-bud and full-bloom decreased from 20.7 to 17.9% d.w., while the content of crude cellulose increased from 14.5 to 17.8% d.w.
For comparison, according to Wojcieszak et al. [96][76], the content of lignin unsuitable for biogas production in various parts of corn (cobs, leaves, stalks, husks), which is a popular substrate used for biogas production in Europe, collected 5–6 months after sowing, ranged from 13.1 to 20.1% d.w. However, corn intended for silage production should be harvested earlier, which translates into a lower lignin content in the biomass. Nowicka et al. [97][77] claimed that the lignin content in the corn silage they tested was 2.6% d.w., while the content of polysaccharides, which after hydrolysis can be processed by microorganisms, was 20.1% and 14.6% d.w. in the case of cellulose and hemicellulose, respectively.
Table 2.
Contents of cellulose, hemicellulose and lignin in biomass of selected cover crops.
Species Cellulose

(% d.w.)		 Hemicellulose

(% d.w.)		 Lignin

(% d.w.)		 References
Grasses 37.85 27.33 9.65 [98][78]
Grass silage 34.15 24.27 2.78 [99][79]
Sunflower (Helianthus annuus L.) 34.06 5.18 7.72 [98][78]
Fodder radish (Raphanus sativus L.), flowering stage 8.5 17.6 9.43 [100][80]
Fodder radish (Raphanus sativus L.), maturation stage 18.99 14.54 10.63
Pearl millet (Pennisetum glaucum), flowering stage 22.44 29.87 4.7
Pearl millet (Pennisetum glaucum), maturation stage 12.96 27.64 10.56
Orchard grass, cocksfoot (Dactylis glomerata L.) 52.3 42.9 6.6 [101][81]
Abruzzi rye (Secale cereal L.) 25.26 25.17 2.56 [102][82]
Black oat (Avena Strigosa Schreb) 46.2 27.84 9.12 [103][83]
Black oat (Avena strigosa Schreb) 25.17 20.82 1.77 [102][82]
Winter barley (Hordeum vulgare L.). 19.36 20.88 1.42 [102][82]
Field (winter) pea (Pisum sativum L.) different varieties 26.8–38.7 5.1–11.8 l.d. [104][84]
Field (winter) pea (Pisum sativum L.) 17 different genotypes 20.3–36.16 9.18–10.8 4.86–10.2 [105][85]
Crimson clover (Trifolium incarnatum) 26–61.3 4.5–8.0 [103][83]
Crimson clover (Trifolium incarnatum) 17.33 12.65 3.37 [106][86]
Crimson clover (Trifolium incarnatum) 25.58 9.53 3.35 [102][82]
Crimson clover (Trifolium incarnatum) 29.1–36.88 * 10.8–11.12 * 7.5–10.10 * [105][85]
Hairy vetch (Vicia villosa Roth) 26.84–33.53 10.84–11.63 8.3–11.2 [107][87]
Hairy vetch (Vicia villosa Roth) 28.4 10.12 7.57 [103][83]
Hairy vetch (Vicia villosa Roth) 27.24 14.29 4.86 [102][82]
Common vetch (Vicia sativa L.). 13.4 25.8 7.3 [108][88]
White lupine (Lupinus albus L.) silage 40.34 13.6 7.63 [109][89]
Broad bean (Vicia faba L.) silage 28.12 18.59 7.22 [109][89]
Switchgrass (Panicum virgatum) 39.5–45 20.3–31.5 12–20 [110][90]
l.d.—lack of data; * values grown with harvest timings
Considering the data given in Table 2, it can be stated that cellulose dominates in crude fiber fraction, reaching up to 50% d.w., while the content of lignin in CCC biomass is usually lower than 10% d.w. Late harvest usually leads to an increase in the lignin content in CCC biomass, causing a decrease in biodegradability. Thus, the time of plant harvesting is a very important factor that influences the biomass’ suitability for biogas production.
Other important chemical properties indicating the suitability of plant biomass for energy use in biochemical conversion processes are related to the content of carbon and nitrogen and the mutual ratio of these parameters C/N, as well as the content of macroelements such as P, K, Ca, Mg and numerous microelements, which influence the functioning of microorganisms responsible for the biodegradation process of biomass.
The carbon content in the dry matter of catch crops in the aboveground part usually ranges from 40 to 50% [111,112][91][92]. The nitrogen concentration in plant biomass varies depending on the species, ranging from 13.6 to 52 g N kg dry d.w.−1 in the biomass of brassicas and grasses, respectively. Higher concentrations of nitrogen, from 43 to 84 g N kg of d.w.−1, are found in legumes [53,112][32][92]. Kwiatkowski et al. (2019) [41][20] found the nitrogen content in the biomasses of white mustard and lacy phacelia to be 38.6–39.321 g N/kg dry d.w.−1 and 2.74–3.21 g N kg d.w.−1, respectively. Studies carried out in France and Denmark showed that the total nitrogen amount in catch crops’ biomass harvested on 1 hectare ranged from 10 to 171 kg N ha−1 for legumes, and from 9 to 89 kg N ha−1 for non-legumes, while the C:N ratio ranged widely, from 9 to 40, thus sometimes going beyond the range considered optimal for microorganisms’ growth, which is estimated to be between 20 and 35 [113,114][93][94]. According to the study of Szwarc et al. [99][79], the C:N ratio of grass silage was ca. 23.
The concentrations of other important nutrients in the catch crops’ biomasses, belonging to grasses, legumes and brassicas, were: phosphorus—2–8.2 g kg d.w.−1, potassium—15–52.8 g kg d.w.−1, magnesium—0.9–4 g kg d.w.−1 [41[20][32],53], calcium—21.4–26.6 g kg d.w.−1 [41][20] and sulfur—1–9 kg d.w.−1 [53][32]. An excessive content of sulfur in biomass poses a threat to the proper course for both the biochemical and thermal methods of biomass conversion into energy. In the case of anaerobic digestion, problems are related to the production of H2S, which inhibits the growth of microorganisms [115][95]. The solution is to modify the composition of the substrate so that the optimal value of C:S in the feedstock is over 40 [116][96]. In the case of combustion, the high content of sulfur in the fuel leads to SO2 production. In general, the content of sulfur in plant biomass is low [117][97].

3. Energy Potential of CCC Biomass Converted into Biogas

The basis for the economic assessment of the suitability of plant biomass for use in the energy sector is the value of energy that can be produced from biomass harvested per hectare of crop area per year (MJ ha−1 yr−1). This value is calculated based on the yield of the raw material (Mg ha−1 yr−1), which is an energy carrier, and its energy value (MJ Mg−1). In the case of the methane fermentation process, the measure of the suitability of CCC biomass for biogas production is its specific methane yield or biomethane potential, which is the volume of methane obtained per mass unit of substrate (m3 CH4 Mg−1) and biomass yield obtained per hectare per year (Mg ha−1 yr−1). On this basis, the methane yield per hectare per year (m3 CH4 ha−1 yr−1) is calculated. Assuming the lower heating value of methane (35.8 MJ Nm−3), the energy of biomass per mass unit or cropping area unit is estimated.
According to Möller and Müller [118][98], during anaerobic fermentation, up to 95% of the carbon contained in the substrate is converted into gaseous components of biogas (CH4 and CO2). In the case of energy catch crops examined by Bareha et al. [111][91], the amount of carbon converted into biogas during this process ranged from 43 to 74%, while in the case of animal manure, it is 36–41%. The degree of conversion depends on many factors, including the content of water-soluble organic compounds, polysaccharides, lignin, C:N ratio, the kind of biomass pretreatment, e.g., grinding or ensiling, and the operational conditions of anaerobic digestion.
Th value of the specific methane yield of the aboveground biomass of different CCC plants is similar. According to Graß et al. [119][99], the methanogenic potential of the biomass of plant species, such as turnip rape, rye, winter pea, maize, sorghum and sunflower cultivated in different combinations in double-cropping systems in Germany harvested in the vegetative phase, only slightly differed among the particular species. Thus, the yield of biomass was a key factor determining the potential of these plants for biogas production in the fermentation process. The similarity of the specific methane yield values is also indicated by the data presented in Table 3.
Table 3.
Specific methane yields of selected catch and cover crop biomass.
Crop Part of the Plant Methane Yield (m3 Mg−1VS) Reference
White mustard (Sinapis alba) Tops 352 [120][100]
Oil seed rape (Brassica napus spp. oleifera) Straw 420 [121][101]
Radish (Raphanus sativus) Shoots 293–304 [122][102]
Rape (Brassica napus arvensis) Tops 334 [120][100]
Rape (Brassica napus) Not reported 340 [123][103]
Winter rye (Secale cereale montanum) Straw 360 [121][101]
Rye (Secale cereale) Whole plants 140–275 [87][67]
Triticale (Triticale) Whole plants 212–286 [87][67]
Triticale (Triticale) Whole plants 396 [124][104]
Faba bean (Vicia faba) Straw 440 [125][105]
Faba bean (Vicia faba) Whole plants 387 [126][106]
Ryegrass (Lolium sp.) - 410 [123][103]
Ryegrass (Lolium sp.) - 490 [104][84]
Clover (Trifolium sp.) Vegetative stage 210 [127][107]
Clover (Trifolium sp.) Flowering stage 140 [127][107]
Grass hay - 350 [127][107]
Oat - 260 [127][107]
Lupine (Lupinus polyphyllus) Whole plants 310–360 [120][100]
Vetch oat (50% Vicia sativa) Whole plants 400–410 [120][100]
Red clover (Trifolium pratense) Whole plants 310–320 [120][100]
Red clover (Trifolium pratense) Whole plants 238–293 [128][108]
Red/white clover–ryegrass Trifolium pratense, Trifolium repens L, Lolium perenne L.) Whole plants 281–315 [128][108]
Corn Corn stover 256 ± 15 [129][109]
According to them, the values of this parameter of the raw biomass of different cover crops ranged from 140 to 490 m3 CH4 Mg−1 VS (VS—volatile solids), and the highest value was observed in the case of ryegrass. The literature values reported by Amon et al. [87][67], which ranged from 213 to 442 m3 Mg−1 VS, are in this scope. In addition, the results of the studies of Molinuevo-Salces et al. [30][8], carried out in Denmark on 10 types of catch crops (single species: white mustard, yellow lupin, oil seed radish, lupin, bean; mixed species: white mustard and common vetch, oil seed rape and winter vetch, perennial rye and Persian clover, winter ryegrass and winter vetch, triticale and winter vetch) were comparable with the values given above. The methane potential was between 229 and 450 m3 Mg−1 VS, and its highest values were obtained in the case of a mixture of rapeseed and winter vetch (399–415 m3 Mg−1 VS), and oilseed radish (368–450 m3 Mg−1 VS) cultivated in one of the locations tested in the study (Holstebro), while the lowest values were obtained in the case of white mustard (239–252 m3 Mg−1 VS), regardless of the location of the crops. The biomethane potential of the raw biomass of CCCs usually does not differ from the potential of raw corn biomass, which is 256 ± 15 m3 Mg−1 VS [129][109].
A serious limitation in the energetic use of the biomass of plants is the difficulty in maintaining its chemical properties for a long time. The biomasses of CCC plants harvested in the low-maturity phase, useful for biogas production, have a high water content, and are low in their resistance to biodegradation during storage. This is an unfavorable feature when taking into account the efficiency of methane production because it leads to carbon losses before the process of organic matter conversion into biogas. However, research indicates that this problem can be dealt with by the use of ensiling, commonly practiced as a method of preserving plant biomass for animal feed. This process involves the transformation of organic matter in the fermentation process carried out by lactic acid bacteria [130][110]. During the process, organic matter is lost. However, as reported by Borreani et al. [131][111] based on the results of their literature review, these losses may vary widely from 1 to 34% depending on the process conditions. According to Villa et al. [132][112], a properly conducted ensiling process allows for the conservation of up to 93% of the gross energy of biomass. The process leads to a change in the chemical composition that is beneficial for methanogens, which involves the production of organic acids that are easily accessible to them. According to Franco et al. [133][113], the most preferable features of feedstock subjected to ensiling are the high content of accessible carbohydrates, low buffering capacity and low moisture. The research conducted by Van Vlierberghe et al. [134][114] showed that the high moisture in CCC biomass leads to the production of leachate, and thereby causes losses in the amount of valuable substrates for biogas production. Their study confirmed that the addition of co-substrates with a high water retention capacity, such as bio-waste and manures, allows the organic matter losses to be limited and the high biogas potential of the silage to be maintained.
Herrmann et al. [135][115] showed that the reference values of the methane yields of silages of different crop species, such as Italian ryegrass, fodder radish, phacelia, annual ryegrass, spring barley, rapeseed, buckwheat, alfalfa, clover/grass mixtures, alfalfa/grass mixture, oat/fodder vetch mixture, mustard, Bokhara clover and buckwheat/phacelia mixture, related to maize silage, ranged from 57 to 109%, and the lowest value was observed in the case of the alfalfa/grass mixture, and the highest one in the case of the oat/fodder vetch and clover/grass mixtures. The mean methane yield of maize silage determined in this study was 354.6 m3 Mg−1 VS. Hutňan [136][116] found a lower value for the specific methane yield of maize silage, which was in the range 206–283 m3 Mg−1 VS.
In Europe, aboveground catch biomass rarely exceeds 5 Mg d.w. ha−1 [53][32]. The biomass yield of CCCs can vary depending on crop species, soil properties and climatic conditions. According to Hansen et al. [53][32], the production of biomass in Denmark remains highly variable, and it ranges from 3 to 15 Mg d.w. ha−1 for summer energy crops, and from 2 to 16 Mg d.w. ha−1 for winter energy crops. According to their observations, it was difficult to obtain a dense and uniform cover in the summer season due to the lack of water in the soil, while the low number of sunny days was the limiting factor in autumn.
Many studies have been conducted to maximize CCC biomass yield, e.g., by modification in the selection of the plants used in double-cropping systems in order to increase their potential in energy production [119,124,127,137,138][99][104][107][117][118].

References

  1. Finch, H.J.S.; Samuel, A.M.; Lane, G.P.F. (Eds.) Woodhead Publishing Series in Food Science, Technology and Nutrition, Lockhart & Wiseman’s Crop Husbandry Including Grassland, 9th ed.; Woodhead Publishing: Cambridge, UK, 2014; ISBN 9781782423713.
  2. Hołubowicz-Kliza, G. Uprawa Poplonów (Catch Crops Cultivation); Instrukcja Upowszechnieniowa (Dissemination Instruction) 166; Wyd. IUNG-PIB: Puławy, Poland, 2010. (In Polish)
  3. Thomas, F.; Archambeaud, M. Międzyplony w Praktyce; Oficyna Wydawnicza OIKOS: Warszawa, Poland, 2019; ISBN 978-83-64843-21-1. (In Polish)
  4. Szerencsits, M.; Weinberger, C.; Kuderna, M.; Feichtinger, F.; Erhart, E.; Maier, S. Biogas from Cover Crops and Field Residues: Effects on Soil, Water, Climate and Ecological Footprint. World Acad. Eng. Technol. Int. J. Environ. Ecol. Eng. 2015, 9, 413–416.
  5. Van Eerd, L.L.; Chahal, I.; Peng, Y.; Awrey, J.C. Influence of cover crops at the four spheres: A review of ecosystem services, potential barriers, and future directions for North America. Sci. Total Environ. 2023, 858, 159990.
  6. Vogeler, I.; Hansen, E.M.; Thomsen, I.K. The effect of catch crops in spring barley on nitrate leaching and their fertilizer replacement value. Agric. Ecosyst. Environ. 2022, 343, 108282.
  7. Gage, D.J. Infection and invasion of roots by symbiotic, nitrogen-fixing rhizobia during nodulation of temperate legumes. Microbiol. Mol. Biol. Rev. 2004, 68, 280–300.
  8. Molinuevo-Salces, B.; Larsen, S.U.; Ahring, B.K.; Uellendahl, H. Biogas production from catch crops: Evaluation of biomass yield and methane potential of catch crops in organic crop rotations. Biomass Bioenergy 2013, 59, 285–292.
  9. Żuk-Gołaszewska, K.; Wanic, M.; Orzech, K. The role of catch crops in field plant production—A review. J. Elem. 2019, 24, 575–587.
  10. Richards, A.; Estaki, M.; Úrbez-Torres, J.R.; Bowen, P.; Lowery, T.; Hart, M. Cover Crop Diversity as a Tool to Mitigate Vine Decline and Reduce Pathogens in Vineyard Soils. Diversity 2020, 12, 128.
  11. Ma, W.; Tang, S.; Dengzeng, Z.; Zhang, D.; Zhang, T.; Ma, X. Root exudates contribute to belowground ecosystem hotspots: A review. Front. Microbiol. 2022, 13, 937940.
  12. NPGS National Plant Germplasm System. United State Department of Agriculture. Agricultural Research Service. National Germplasm Resources Laboratory. Available online: https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch?t=pnlspecies (accessed on 25 October 2023).
  13. USDA. Plant Guide. Available online: https://plants.usda.gov/home (accessed on 25 October 2023).
  14. Gerhards, R.; Schappert, A. Advancing cover cropping in temperate integrated weed management. Pest Manag. Sci. 2020, 6, 42–46.
  15. Büchi, L.; Wendling, M.; Amossé, C.; Jeangros, B.; Charles, R. Cover crops to secure weed control strategies in a maize crop with reduced tillage. Field Crops Res. 2020, 247, 107583.
  16. Liu, X.; Hannula, S.E.; Li, X.; Hundscheid, M.P.J.; klein Gunnewiek, P.J.A.; Clocchiatti, A.; Ding, W.; de Boer, W. Decomposing cover crops modify root-associated microbiome composition and disease tolerance of cash crop seedlings. Soil Biol. Biochem. 2021, 160, 108343.
  17. Heuermann, D.; Döll, S.; Schweneker, S.; Feuerstein, U.; Gentsch, N.; von Wirén, N. Distinct metabolite classes in root exudates are indicative for field- or hydroponically-grown cover crops. Front. Plant Sci. 2023, 14, 1122285.
  18. Toom, M.; Talgre, L.; Mäe, A.; Tamm, S.; Narits, L.; Edesi, L.; Haljak, M.; Lauringson, E. Selecting winter cover crop species for northern climatic conditions. Agron. J. 2019, 35, 263–274.
  19. Gentsch, N.; Riechers, F.L.; Boy, J.; Schwenecker, D.; Feuerstein, U.; Heuermann, D.; Guggenberger, G. Cover crops improve soil structure and change organic carbon distribution in macroaggregate fractions. EGUsphere, 2023; preprint.
  20. Kwiatkowski, C.; Haliniarz, M.; Kolodziej, B.; Harasim, E.; Tomczyńska-Mleko, M. Content of some chemical components in carrot (Daucus carota L.) roots depending on growth stimulators and stubble crops. J. Elem. 2015, 20, 933–943.
  21. Ren, L.; Nest, T.V.; Ruysschaert, G.; D’Hose, T.; Cornelis, W.M. Short-term effects of cover crops and tillage methods on soil physical properties and maize growth in a sandy loam soil. Soil Tillage Res. 2019, 192, 76–86.
  22. Arlauskienė, A.; Šarūnaitė, L. Cover Crop Yield, Nutrient Storage and Release under Different Cropping Technologies in the Sustainable Agrosystems. Plants 2023, 12, 2966.
  23. Vogeler, I.; Hansen, E.M.; Thomsen, I.K.; Østergaard, H.S. Legumes in catch crop mixtures: Effects on nitrogen retention and availability, and leaching losses. J. Environ. Manag. 2019, 239, 324–332.
  24. Gieske, M.F.; Ackroyd, V.J.; Baas, D.G.; Mutch, D.R.; Wyse, D.L.; Durgan, B.R. Brassica Cover Crop Effects on Nitrogen Availability and Oat and Corn Yield. Soil Fertil. Crop Nutr. 2016, 108, 151–161.
  25. Murrell, E.G.; Schipanski, M.E.; Finney, D.M.; Hunter, M.C.; Burgess, M.; LaChance, J.C.; Baraibar, B.; White, C.M.; Mortensen, D.A.; Kaye, J.P. Achieving Diverse Cover Crop Mixtures: Effects of Planting Date and Seeding Rate. Agron. J. 2017, 109, 259–271.
  26. Findlay, N.; Manson, A. Cover crops: What Are They and Why ARE they Used. Agri Udatem Information from the KZN Department of Agriculture. Environmental Affairs & Rural Development, 2011/02. Available online: https://www.kzndard.gov.za/images/Documents/ (accessed on 12 September 2023).
  27. He, Q.; Liu, D.L.; Wang, B.; Cowie, A.; Simmons, A.; Waters, C.; Li, L.; Feng, P.; Li, Y.; de Voil, P.; et al. Modelling interactions between cowpea cover crops and residue retention in Australian dryland cropping systems under climate change, Agriculture. Ecosyst. Environ. 2023, 353, 108536.
  28. Soares, M.B.; Tavanti, R.F.R.; Rigotti, A.R.; de Lima, J.P.; da Silva Freddi, O.; Petter, F.A. Use of cover crops in the southern Amazon region: What is the impact on soil physical quality? Geoderma 2021, 384, 114796.
  29. Perdigão, A.; Coutinho, J.; Moreira, N. Cover crops as nitrogen source for organic farming in Southwest Europe. ISHS Acta Hortic. 2010, 933, 355–361.
  30. Pietrzykowski, M.; Gruba, P.; Sproull, G. The effectiveness of yellow lupine (Lupinus luteus L.) green manure cropping in sand mine cast reclamation. Ecol. Eng. 2017, 102, 72–79.
  31. Anderson, W.; Knoll, J.E.; Olson, D.; Scully, B.T.; Strickland, T.C.; Webster, T.M. Winter legume cover effects on yields of biomass-sorghum and cotton in Georgia. Agron. J. 2022, 114, 1298–1310.
  32. Hansen, V.; Eriksen, J.; Jensen, L.S.; Thorup-Kristensen, K.; Magid, J. Towards integrated cover crop management: N, P and S release from aboveground and belowground residues. Agric Ecosyst Environ 2021, 313, 107392.
  33. Zhao, M.; Jones, C.M.; Meijer, J.; Lundquist, P.-O.; Fransson, P.; Carlsson, G.; Sara Hallin, S. Intercropping affects genetic potential for inorganic nitrogen cycling by root-associated microorganisms in Medicago sativa and Dactylis glomerata. Appl. Soil Ecol. 2017, 119, 260–266.
  34. Wang, W.; Han, L.; Zhang, X. Winter cover crops effects on soil microbial characteristics in sandy areas of Northern Shaanxi, China. Rev. Bras. Ciênc. Solo 2020, 44, e0190173.
  35. Freeman, O.W.; Kirkham, M.B.; Roozeboom, K.L. Cover Crops to Protect Soil during Winter in the Great Plains of the USA. In Soil Constraints and Productivity; CRC Press: Boca Raton, FL, USA, 2023.
  36. Thomas, B.J.; Fychan, R.; McCalman, H.M.; Sanderson, R.; Thomas, H.; Marley, C.L. Vicia sativa as a grazed forage for lactating ewes in a temperate grassland production system. Food Energy Secur. 2023, 12, e374.
  37. Ortas, I.; Yucel, C. Do mycorrhizae influence cover crop biomass production? Acta Agric. Scand. Sect. B Soil Plant Sci. 2020, 70, 657–666.
  38. Casler, M.D.; Undersander, D.J. Identification of Temperate Pasture Grasses and Legumes. In Horse Pasture Management; Academic Press: Cambridge, MA, USA, 2019.
  39. DuPre, M.E.; Seipel, T.; Bourgault, M.; Boss, D.L.; Menalled, F.D. Predicted climate conditions and cover crop composition modify weed communities in semiarid agroecosystems. Weed Res. 2022, 62, 38–48.
  40. Weinert, C.; de Sousa, R.O.; Bortowski, E.M.; Campelo, M.L.; da Silva Pacheco, D.; dos Santos, L.V.; Deuner, S.; Valente, G.B.; Matos, A.B.; Vargas, V.L.; et al. Legume winter cover crop (Persian clover) reduces nitrogen requirement and increases grain yield in specialized irrigated hybrid rice system. Eur. J. Agron. 2023, 142, 126645.
  41. Caswell, K.; Wallace, J.M.; Curran, W.S.; Mirsky, S.B.; Ryan, M.R. Cover Crop Species and Cultivars for Drill-Interseeding in Mid-Atlantic Corn and Soybean. Agron. J. 2019, 111, 1060–1067.
  42. Khanal, C.; Harshman, D. Evaluation of summer cover crops for host suitability of Meloidogyne enterolobii. Crop Prot. 2022, 151, 105821.
  43. Vitalini, S.; Orlando, F.; Vaglia, V.; Bocchi, S.; Iriti, M. Potential Role of Lolium multiflorum Lam. in the Management of Rice Weeds. Plants 2020, 9, 324.
  44. Behnke, G.D.; Villamil, M.B. Cover crop rotations affect greenhouse gas emissions and crop production in Illinois, USA. Field Crops Res. 2019, 241, 107580.
  45. Poudel, P.; Ødegaard, J.; Mo, S.J.; Andresen, R.K.; Tandberg, H.A.; Cottis, T.; Solberg, H.; Bysveen, K.; Dulal, P.R.; Mousavi, H.; et al. Italian Ryegrass, Perennial Ryegrass, and Meadow Fescue as Undersown Cover Crops in Spring Wheat and Barley: Results from a Mixed Methods Study in Norway. Sustainability 2022, 14, 13055.
  46. Wang, H.; Beule, L.; Zang, H.; Pfeiffer, B.; Ma, S.; Karlovsky, P.; Dittert, K. The potential of ryegrass as cover crop to reduce soil N2O emissions and increase the population size of denitrifying bacteria. Soil Sci. 2021, 72, 1447–1461.
  47. Ruis, S.J.; Blanco-Canqui, H.; Creech, C.F.; Koehler-Cole, K.; Elmore, R.W.; Francis, C.A. Cover Crop Biomass Production in Temperate Agroecozones. Agron. J. 2019, 111, 1535–1551.
  48. Elhakeem, A.; van der Werf, W.; Ajal, J.; Lucà, D.; Claus, S.; Vico, R.A.; Bastiaans, L. Cover crop mixtures result in a positive net biodiversity effect irrespective of seeding configuration. Agric. Ecosyst. Environ. 2019, 285, 106627.
  49. Khan, Q.A.; McVay, K.A. Productivity and stability of multi-species cover crop mixtures in the northern great plains. Agron. J. 2019, 111, 1817–1827.
  50. Heuermann, D.; Gentsch, N.; Boy, J.; Schweneker, D.; Feuerstein, U.; Groß, J.; Bauer, B.; Guggenberger, G.; von Wirén, N. Interspecific competition among catch crops modifies vertical root biomass distribution and nitrate scavenging in soils. Sci. Rep. 2019, 9, 11531.
  51. Heuermann, D.; Gentsch, N.; Guggenberger, G.; Reinhold-Hurek, B.; Schweneker, D.; Feuerstein, U.; Heuermann, M.C.; Groß, J.; Kümmerer, R.; Bauer, B.; et al. Catch crop mixtures have higher potential for nutrient carry-over than pure stands under changing environments. Eur. J. Agron. 2022, 136, 126504.
  52. Elhakeem, A.; Bastiaans, L.; Houben, S.; Couwenberg, T.; Makowski, D.; van der Werf, W. Do cover crop mixtures give higher and more stable yields than pure stands? Field Crops Res. 2021, 270, 108217.
  53. Florence, A.M.; McGuire, A.M. Do diverse cover crop mixtures perform better than monocultures? A systematic review. Agron. J. 2020, 112, 3513–3534.
  54. Plumhoff, M.; Connell, R.K.; Bressler, A.; Blesh, J. Management history and mixture evenness affect the ecosystem services from a crimson clover-rye cover crop. Agric. Ecosyst. Environ. 2022, 339, 108155.
  55. Sievers, T.; Cook, R.L. Aboveground and Root Decomposition of Cereal Rye and Hairy Vetch Cover Crops. Soil Fertil. Plant Nutr. 2018, 82, 147–155.
  56. Wright, C.; Ghezzi-Haeft, J. Hairy Vetch and Triticale Cover Crops for N Management in Soils. Open J. Soil Sci. 2020, 10, 244–256.
  57. Sanderson, M.; Johnson, H.; Hendrickson, J. Cover Crop Mixtures Grown for Annual Forage in a Semi-Arid Environment. Agron. J. 2018, 110, 525–534.
  58. Franco, J.G.; Gramig, G.G.; Beamer, K.P.; Hendrickson, J.R. Cover crop mixtures enhance stability but not productivity in a semi-arid climate. Agron. J. 2021, 113, 2664–2680.
  59. Li, H.; Fang, Z.; Smith, R.I.; Yang, S. Efficient valorization of biomass to biofuels with bifunctional solid catalytic materials. Prog. Energy Combust. Sci. 2016, 55, 98–194.
  60. Owczuk, M.; Kołodziejczyk, K. Ocena możliwości wykorzystania słomy i wytłoków z lnicznika siewnego jako alternatywnego surowca energetycznego (Assessment of the possibility of using straw and pomace from camelina as an alternative energy raw material). Chemik 2011, 6, 537–539. (In Polish)
  61. Mishra, S.; Upadhyay, R.K. Review on biomass gasification: Gasifiers, gasifying mediums, and operational parameters. Mater. Sci. Energy Technol. 2021, 4, 329–340.
  62. Westerhof, R.J.M.; Kuipers, N.J.M.; Kersten, S.R.A.; van Swaaij, W.P.M. Controlling the Water Content of Biomass Fast Pyrolysis Oil. Ind. Eng. Chem. Res. 2007, 46, 9238–9247.
  63. Shafizadeh, A.; Danesh, P. Biomass and Energy Production: Thermochemical Methods. In Biomass, Biorefineries and Bioeconomy; Samer, M., Ed.; IntechOpen: Rijeka, Croatia, 2022.
  64. Koca, Y.O.; Erekul, O. Changes of dry matter, biomass and relative growth rate with different phenological stages of corn. Agric. Agric. Sci. Procedia 2016, 10, 67–75.
  65. Piskier, T. Method of estimation of the caloric value of the biomass. Part I—Biomass energy potential. J. Mech. Energy Eng. 2017, 1, 189–194.
  66. Rabelo, C.H.S.; De Rezende, A.V.; Rabêlo, F.H.S.; Basso, F.C.; Härter, C.J.; Reis, R.A. Chemical composition, digestibility and aerobic stability of corn silages harvested at different maturity stages. Rev. Caatinga Mossoró 2015, 28, 107–116.
  67. Doyar, B.; Kiraz, A.B. Determination of Nutritional Value and Methane Production Potential of Phacelia tanacetifolia in Different Stages of Growth. Indian J. Anim. Res. 2023, BF-1575, 1–6.
  68. Tekeli, A.S.; Ateş, E.; Varol, F. Nutritive Values of Some Annual Clovers (Trifolium sp.) at Different Growth Stages. J. Cent. Eur. Agric. 2005, 6, 323–330.
  69. Iakovou, E.; Karagiannidis, A.; Vlachos, D.; Toka, A.; Malamakis, A. Waste Biomass-To-Energy Supply Chain Management: A Critical Synthesis. Waste Manag. 2010, 30, 186–187.
  70. Amon, T.; Amon, B.; Kryvoruchko, V.; Machmuller, A.; Hopfner-Sixt, K.; Bodiroza, V.; Hrbek, R.; Friedel, J.; Pötsch, E.; Wagentristl, H.; et al. Methane production through anaerobic digestion of various energy crops grown in sustainable crop rotations. Bioresour. Technol. 2007, 98, 3204–3212.
  71. Seppäla, M.; Paavola, T.; Lehtomaki, A.; Rintala, J. Biogas production from boreal herbaceous grasses—Specific methane yield and methane yield per hectare. Bioresour. Technol. 2009, 100, 2952–2958.
  72. Coban, H.; Miltner, A.; Elling, F.J.; Hinrichs, K.U.; Kästner, M. The contribution of biogas residues to soil organic matter formation and CO2 emissions in an arable soil. Soil Biol. Biochem. 2015, 86, 108–115.
  73. Möller, K. Effects of anaerobic digestion on soil carbon and nitrogen turnover, N emissions, and soil biological activity. A review. Agron. Sustain. Dev. 2015, 35, 1021–1041.
  74. Pokój, T.; Klimiuk, E.; Bułkowska, K.; Kowal, P.; Ciesielski, S. Effect of Individual Components of Lignocellulosic Biomass on Methane Production and Methanogen Community Structure. Waste Biomass Valorization 2020, 11, 1421–1433.
  75. Chaves, A.V.; Waghorn, G.C.; Tavendale, M.H. A simplified method for lignin measurement in a range of forage species. Proc. New Zealand Grassl. Assoc. 2002, 64, 129–133.
  76. Wojcieszak, D.; Przybył, J.; Ratajczak, I.; Goliński, P.; Janczak, D.; Waśkiewicz, A.; Szentner, K.; Woźniak, M. Chemical composition of maize stover fraction versus methane yield and energy value in fermentation process. Energy 2020, 198, 17258.
  77. Nowicka, A.; Zieliński, M.; Dębowski, M.; Dudek, M. Progress in the Production of Biogas from Maize Silage after Acid-Heat Pretreatment. Energies 2021, 14, 8018.
  78. Tutt, M.; Olt, J. Suitability of various plant species for bioethanol production. Agron. Res. 2011, 1, 261–267.
  79. Szwarc, D.; Nowicka, A.; Głowacka, K. Cross-Comparison of the Impact of Grass Silage Pulsed Electric Field and Microwave-Induced Disintegration on Biogas Production Efficiency. Energies 2022, 15, 5122.
  80. Moreira de Carvalho, A.; Pereira de Souza, L.L.; Guimarães, R., Jr.; Castro Alves, P.C.A.; Vivaldi, L.J. Cover plants with potential use for crop-livestock integrated systems in the Cerrado region. Pesq. Agropec. Bras. 2011, 46, 1200–1205.
  81. Kumar, B.; Bhardwaj, N.; Agrawal, K.; Chaturvedi, V.; Verma, P. Current perspective on pretreatment technologies using lignocellulosic biomass: An emerging biorefinery concept. Fuel Process. Technol. 2020, 199, 106244.
  82. Shahi, N.; Joshi, G.; Min, B. Potential sustainable biomaterials derived from cover crops. BioResources 2020, 15, 5641–5652.
  83. Ferreira, P.A.A.; Girotto, E.; Trentin, G.; Miotto, A.; Melo, G.W.D.; Ceretta, C.A.; Kaminski, J.; Frari, B.K.D.; Marchezan, C.; Silva, L.O.S.; et al. Biomass decomposition and nutrient release from black oat and hairy vetch residues deposited in a vineyard. Rev. Bras. Ciênc. Solo 2014, 38, 1621–1632.
  84. Gebremeskele, Y.; Gebrem, A.E.; Melaku, S. Crop–Livestock Interaction for Improved Productivity: Effect of Selected Varieties of Field Pea (Pisum sativum L.) on Grain and Straw Parameters. In Challenges and Opportunities for Agricultural 137 Intensification of the Humid Highland Systems of Sub-Saharan Africa; Vanlauwe, B., van Asten, P., Blomme, G., Eds.; Springer International Publishing: Cham, Switzerland, 2014.
  85. Vann, R.A.; Reberg-Horton, S.C.; Castillo, M.S.; Murphy, J.P.; Martins, L.B.; Mirsky, S.B.; Saha, U.; McGee, R.J. Differences among eighteen winter pea genotypes for forage and cover crop use in the southeastern United States. Crop Sci. 2020, 61, 947–965.
  86. Brozzoli, V.; Bartocci, S.; Terramoccia, S.; Contò, G.; Federici, F.; D’Annibale, A.; Petruccioli, M. Stoned olive pomace fermentation with Pleurotus species and its evaluation as a possible animal feed. Enzym. Microb. Technol. 2010, 46, 223–228.
  87. Woodruff, L.K.; Kissel, D.E.; Cabrera, M.L.; Habteselassie, M.Y.; Hitchcock, R.; Gaskin, J.; Vigil, M.; Sonon, L.; Saha, U.; Romano, N.; et al. A Web-Based Model of N Mineralization from Cover Crop Residue Decomposition. Nutr. Manag. Soil Plant Anal. 2018, 82, 983–993.
  88. Lanyasunya, P.; Rong Wang, H.; Abdulrazak, S.A.; Mukisira, E.A.; Zhang, J. In sacco determination of dry matter, organic matter and cell wall degradation characteristics of common vetch (Vicia sativa L.). Trop. Subtrop. Agroecosystems 2006, 6, 117–123.
  89. Kintl, A.; Huňady, I.; Vítěz, T.; Brtnický, M.; Sobotková, J.; Hammerschmiedt, T.; Vítězová, M.; Holátko, J.; Smutný, V.; Elbl, J. Effect of Legumes Intercropped with Maize on Biomass Yield and Subsequent Biogas Production. Agronomy 2023, 13, 2775.
  90. Ning, P.; Yang, G.; Hu, L.; Sun, J.; Shi, L.; Zhou, Y.; Wang, Z.; Yang, J. Recent advances in the valorization of plant biomass. Biotechnol. Biofuels 2021, 14, 102.
  91. Bareha, Y.; Girault, R.; Jimenez, J.; Trémier, A. Characterization and prediction of organic nitrogen biodegradability during anaerobic digestion: A bioaccessibility approach. Bioresour. Technol. 2018, 263, 425–436.
  92. Bertrand, I.; Viaud, V.; Daufresne, T.; Pellerin, S.; Recous, S. Stoichiometry constraints challenge the potential of agroecological practices for the soil C storage. A review. Agron. Sustain. Dev. 2019, 39, 54.
  93. Khalid, A.; Arshad, M.; Anjum, M.; Mahmood, T.; Dawson, L. The anaerobic digestion of solid organic waste. Waste Manag. 2011, 31, 1737–1744.
  94. Mao, C.; Feng, Y.; Wang, X.; Ren, G. Review on research achievements of biogas from anaerobic digestion. Renew. Sustain. Energy Rev. 2015, 45C, 540–555.
  95. Yang, G.; Zhang, G.; Zhuan, R.; Yang, A.; Wang, Y. Transformations, Inhibition and inhibition control methods of sulfur in sludge anaerobic digestion: A review. Curr. Org. Chem. 2016, 20, 2780–2789.
  96. Peu, P.; Picard, S.; Diara, A.; Girault, R.; Béline, F.; Bridoux, G.; Dabert, P. Prediction of hydrogen sulphide production during anaerobic digestion of organic substrates. Bioresour. Technol. 2012, 121, 419–424.
  97. Greinert, A.; Mrówczyńska, M.; Grech, R.; Szefner, W. The Use of Plant Biomass Pellets for Energy Production by Combustion in Dedicated Furnaces. Energies 2020, 13, 463.
  98. Möller, K.; Müller, T. Effects of anaerobic digestion on digestate nutrient availability and crop growth: A review. Eng. Life Sci. 2012, 12, 242–257.
  99. Graß, R.; Heuser, F.; Stülpnagel, R.; Piepho, H.P.; Wachendorf, M. Energy crop production in double-cropping systems: Results from an experiment at seven sites. Eur. J. Agron. 2013, 51, 120–129.
  100. Lehtomäki, A.; Viinikainen, T.A.; Rintala, J. Screening boreal energy crops residues for methane biofuel production. Biomass Bioenergy 2008, 32, 541–550.
  101. Petersson, A.; Thomsen, M.H.; Hauggaard-Nielsen, H.; Thomsen, A.B. Potential bioethanol and biogas production using lignocellulosic biomass from winter rye, oil seed rape and faba bean. Biomass Bioenergy 2007, 31, 812–819.
  102. Gunaseelan, N. Biochemical methane potential of fruits and vegetable solid waste feedstocks. Biomass Bioenergy 2004, 26, 389–399.
  103. Weiland, P. Production and energetic use of biogas from energy crops and wastes in Germany. Appl. Biochem. Biotech. 2003, 109, 263–274.
  104. Molinuevo-Salces, B.; Fernández-Varela, R.; Uellendahl, H. Key factors influencing the potential of catch crops for methane production. Environ. Technol. 2014, 35, 1685–1694.
  105. Pakarinen, A.; Maijala, P.; Jaakkola, S.; Stoddard, F.L.; Kymäläinen, M.; Viikari, L. Evaluation of preservation methods for improving biogas production and enzymatic conversion yields of annual crops. Biotechnol. Biofuels 2011, 4, 20.
  106. Kaparaju, P.; Luostarinen, S.; Kalmari, E.; Kalmari, J.; Rintala, J. Codigestion of energy crops and industrial confectionery byproducts with cow manure: Batch-scale and farm-scale evaluation. Water Sci Technol. 2002, 45, 275–280.
  107. Heggenstaller, A.H.; Anex, R.P.; Liebman, M.; Sundberg, D.N.; Gibson, L.R. Productivity and nutrient dynamics in bioenergy doublecropping systems. Agron. J. 2008, 100, 1740–1748.
  108. Wahid, R.; Ward, A.J.; Møller, H.B.; Søegaard, K.; Eriksen, J. Biogas potential from forbs and grass-clover mixture with the application of near infrared spectroscopy. Bioresour. Technol. 2015, 198, 124–132.
  109. Fernández-Rodríguez, M.J.; Mushtaq, M.; Tian, L.; Jiménez-Rodríguez, A.; Rincón, B.; Gilroyed, B.H.; Borja, R. Evaluation and modelling of methane production from corn stover pretreated with various physicochemical techniques. Waste Manag. Res. 2022, 40, 698–705.
  110. Wróbel, B.; Nowak, J.; Fabiszewska, A.; Paszkiewicz-Jasińska, A.; Przystupa, W. Dry Matter Losses in Silages Resulting from Epiphytic Microbiota Activity—A Comprehensive Study. Agronomy 2023, 13, 450.
  111. Borreani, G.; Tabacco, E.; Schmidt, R.J.; Holmes, B.J.; Muck, R.E. Silage review: Factors affecting dry matter and quality losses in silages. J. Dairy Sci. 2018, 101, 3952–3979.
  112. Villa, R.; Ortega Rodriguez, L.; Fenech, C.; Anika, O.C. Ensiling for anaerobic digestion: A review of key considerations to maximise methane yields. Renew. Sustain. Energy Rev. 2020, 134, 110401.
  113. Franco, R.T.; Buffière, P.; Bayard, R. Ensiling for biogas production: Critical parameters. A review. Biomass Bioenergy 2016, 94, 94–104.
  114. Van Vlierberghe, C.; Chiboubi, A.; Carrere, H.; Bernet, N.; Santa Catalina, G.; Frederic, S.; Escudie, R. Improving the storage of cover crops by co-ensiling with different waste types: Effect on fermentation and effluent production. Waste Manag. 2022, 154, 136–145.
  115. Herrmann, C.; Plogsties, V.; Willms, M.; Hengelhaupt, F.; Eberl, V.; Eckner, J.; Strauß, C.; Idler, C.; Heiermann, M. Methane production potential of various crop species grown in energy crop rotations. Landtechnik 2016, 71, 194–208.
  116. Hutňan, M. Maize Silage as Substrate for Biogas Production. In Advances in Silage Production and Utilization; da Silva, T., Santo, E.M., Eds.; IntechOpen: Rijeka, Croatia, 2016.
  117. Negri, M.; Bacenetti, J.; Brambila, M.; Manfredini, A.; Cantore, A.; Bocchi, S. Biomethane production from different crop systems of cereals in Northern Italy. Biomass Bioenergy 2014, 63, 321–329.
  118. Wannasek, L.; Ortner, M.; Kaul, H.P.; Amon, B.; Amon, T. Double-cropping systems based on rye, maize and sorghum: Impact of variety and harvesting time on biomass and biogas yield. Eur. J. Agron. 2019, 110, 125934.
More
© Text is available under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)
Video Production Service
Feedback