Crop Residue Collection and Handing Machinery Performance: A Review

Abstract

Increasing demand of agricultural production for human, animal, and industrial requirements is responsible for the enhancement of agricultural and agro-industrial activities. Each step of such activities produces various types of agricultural waste that include crop residue, on-farm livestock and fisheries waste, forest waste, agro-industrial waste, etc. Currently, handling and managing agricultural waste is a challenging task worldwide, especially in the context of environmental pollution control and sustainable agriculture. Thus, efficient management in terms of reuse, recycling, and reduction of agricultural waste is needed not only for the sustainable agriculture but also for farmers’ profitability. Various type of farm machinery is available and are in use to collect the crop residue from the field or directly incorporate the residue into the soil. The incorporated crop residue not only increases the soil fertility but also decreases the greenhouse gases emission due to burning of the crop residue. The crop residue chopper can be a solution of residue management at farmer field level. This chapter provides a review on the crop residue collection handing and incorporation machinery performance and their advancement.

1. Introduction

Crop residue also known as the plant biomass or remnants of crops are natural resources that can be utilized by the farmers for the variety of purpose such as mulching, compositing, as animals feed, rural resident construction, and as energy resource at domestic and industrial level [1]. However, a significant percentage of the crop residue is burnt in the field with the objective to clear the field from stubbles and straw/stalk for time sowing of the next crop [2]. Usually, these crop remnants have a significant chance of refreshing the soil with a substantial amount of plant nutrients. Further, mulching of crop residue maintains the soil temperature, retains soil moisture and mitigate the carbon emission. Crop residue management practice is advised for preserving the natural resources and enhancement of crop productivity [3]. Using modern farm equipment such as combine harvesters, rotavators, and seed drills can lead to increase in crop residue production, primarily from cereals (74%), followed by sugar crops (10%), legumes (8%), tubers (5%), and oilseeds (3%). This ratio of crop residue production shows that the residue production increases with use of the advanced technology [4]. Typically, crop residues are burned in the fields worldwide, particularly in developing countries. This practice not only contributes to air pollution, but also impedes nutrient recycling and negatively impacts soil health by reducing microbial activity and causing carbon loss.

Collecting and handling of agricultural residues from the field is not only an energy- and labor-intensive process, but it is also time-consuming and can delay the sowing of the next crop, ultimately affecting crop yield [5]. Residue burning is not considered a best option to handle the crop residue in these days, as it also releases the greenhouse gases (GHGs) which are injurious to the environment and are a source of global warming [6, 7]. Therefore, effective crop residue management is required through eco-friendly methods to maintain the organic matter and nutrients recycling in the soil.

Therefore, the crop residues handling and management machinery get attention to control the soil degradation, environmental pollution, and to improve the soil health and crop productivity [8]. However, as bio-energy point of view the crop residues would be collected to use as bio-fuel in industry rather than incorporated into the soil, which is in contrast to the concept of conservation agriculture. However, it is crucial to streamline the processes for harvesting, threshing, and transportation, and also to the select varieties with desirable straw properties for bio-fuel generation [6]. Rice crop husk and straw can be used efficiently for the generation of bio-energy. According to empirical estimations, 1 tonne of rice husk has the ability to create between 410 and 570 kWh of electricity, and 290 kg of rice straw can produce 100 kWh [9]. In the rice-growing tropical continent, bio-gas generation from waste combined with animal excrement is an old method. However, its potency and utilization have decreased recently, it still has a lot of benefits, such as enhancing the soil fertility for crop growth [10]. The burning of crops’ residues adversely affects the regional climate, production yields, and the human health [11]. The wide collection of studies on crop residue management’s impact on crop productivity, soil health, environment protection, and energy potential has been made possible by the development of machines for shredding crop residues.

Garg [12] conducted a study to developed paddy straw chopper-cum- spreader. Jia et al., [13] developed a combined stalk– stubble breaking and mulching machine to solve the issues of existing stalk-breaking and stubble- breaking machines. Wang [14] design and developed a straw side spreading and no-till soybean seeding machine to seed soybean in wheat stubble. Elfatih et al., [15] conducted a study to evaluated the performance of the modified rice straw chopper for composting. A performance evaluation study of tractor operated mulcher for paddy straw was conducted by Verma et al., [16]. The effect of residue management of GHGs emissions have been investigated by Lehtinen et al. [17]; Wegner et al., [18]; Zhang et al., [19], on soil health estimated by Bisen and Rahangdale [20]; Clay et al., [21]; Turmel et al., [22]; Yadav and Arora [23]; Zahid et al., [24], crop yield quantification by Hiel et al. [25]; Koga and Tsuji [26]; Paul et al. [27]; Piccoli et al., [28], and as bio-energy product used by Ahiduzzaman et al., [29]; Chauhan et al. [30]; Devi et al., [31]; Fazio and Barbanti [32].

The main objective of this chapter is to present a comprehensively review on crop residue handling and management machinery performance which were designed and used in the field to enhance the crop productivity, environmental pollution control and soil health. This review article is organized in the following manner. First, we discussed the crop residue handling machinery development for different crop trash and then effect of management were explained on soil health, crop production and environment protection. Finally, we summed up the best trash management machinery performance for efficient crop residue management.

2. Crop wise residue handling machinery

2.1 Rice residue management

Rice (Oryza sativa L.) is the most significant crop and considered as the lifeline in Asia. Rice is the most grown food by the people in Asia and it is one of the most valuable and productive one in agroecosystem. The two main tends that evolved the rice cropping in various agroecological regions are intensification and diversification [33]. Limited delay between to improve the crop production to land usage intensification makes it harder to manage these residues, which can affect tillage and sowing procedures for the subsequent crop. However, the Asian farmers are more often burning agricultural remnants as a form of disposal, due to lack of the mechanized and limited technology for the management of huge quantities of residue [34]. Different resource conserving technologies i.e., direct seeding, minimum tillage, bed planting, crop diversification, and proper residue management are potential alternative options to reduce the energy input.

Paddy straw is the valuable asset for the farmers [35]. Therefore, the much needed to manage the paddy residue in the field. Many studies have been conducted about the rice trash management and handling machinery for soil health, crop productivity, and environmental safety control as shown in the Figure 1. Hegazy et al., [37] developed a zero-tillage seed drill which directly seed wheat seed after rice straw-chopping. Two motorized rotors make the straw chopper; the function of the first chopper is to chop the residue and then other removes it from the furrow openers. The straw chopper is assembled in front of the direct seed drill frame. The developed seed drill had field efficiency that varies from 1.89 to 1.94 hm^2/hr. and fuel consumption from 10.88 to 11.6 L/hm² with <11 cm straw chopping efficiency. Sidhu et al., [38]. developed a combo happy seeder that performs the harvesting and drilling process in single pass. The machine is manufactured in such as that it has a narrow strip tillage assembly in front of the sowing tines which consequently improves seed-soil contact on the sandy loam and loam soils. Regatti Venkat, [39] conducting the research study for rise residue management and conclude that the happy seeder technology is the significant solution for the management of crop remnants, and good option for direct seeding of wheat after the harvesting of paddy crop. Kathpalia et al., [40] was conducting the research study to investigate the impact of the crop residue management with happy seeder on the crop productivity enhancement.

Figure 1.

Rice residue handling and management machinery [36].

2.2 Wheat straw management

Globally, approximated 225 Mha area is used to sow the wheat with the production of almost 684 Mt./y. [41]. The increase in sowing area enlarges the on field residue. Scarlat et al., [42] reported that the wheat cropping is one of the most invaluable source of biomass i.e., including wheat husk, mainly as straw, suitable for livestock as bedding, or as raw material for chemical applications. The authors found that the ~17% (w/w) is the production of the chaff as compared to wheat. Therefore, 138 Mt. of the spelt is harvested annually in Europe [41]. In addition, some proportion of the biomass is removed from the soil and does not play any role so the soil organic carbon is obtained from the decomposition of the root in the soil which is remained unaffected [43]. In fact, the remaining proportion of the plant/crop residues in the soil can help to conserve soil fertility and sediment. However, research has indicated that such effect may be widely diverse [44]. Additionally, it was clearly mentioned in the literature that minimizing soil tillage is more likely to decrease soil fertility and loss of soil organic carbon than maintaining the soil cover [45]. Recently, the combine harvesters had lack chaff recovery systems unless appropriate equipment has been installed, that effect the potential of the chaff for variety of purposes [46]. The potential use of agricultural waste products, such as wheat chaff, for non-food applications has encouraged the development of innovative methods by machine manufacturers. While some systems are currently available, others are still in the prototype stage [47]. The standard approach for chaff recovery systems, regardless of the brand, is to collect the chaff at the bottom of the combine harvester’s cleaning shoe system before it falls to the ground and gets lost. When crop yields are low, residue collecting may not be both economically and environmentally feasible [48]. Collecting the chaff separately is the cost ineffective method including the higher cost of the transportation if shipping it without the balling operation [49].

Recently, in Pakistan the combine harvester has adopted at medium and large size farms because it reduces the harvesting time and cost, and grain losses. In Pakistan over 5000 units of combine harvester are working for the harvesting of wheat and rice. The field capacity of the harvester is much higher than that of other harvesting equipment. The limitation of the working of the combine harvester is it works only in the anchored high stubble crop. To mitigate this farmer are demanding the combine harvester which can cut the wheat stubbles and loose straw and chop the residue as fodder i.e., cattle feeding. For this purpose, wheat straw handling and management machinery get attention for the industrial and academic sector to develop and evaluate this machinery.

Zhang et al., [50] developed a stubble chopping shredder machine comprised on different components i.e., cultivator blade, depth cylinder, chopping blade rotor. Mahmood et al., [51] conducted the study to evaluate the performance of wheat straw in field as show in Figure 2. The study concluded that wheat straw chopper is effective and financially profitable technology for the farmers which saves the stubbles for the cattle feed. Suardi et al., [52] compared the two-wheat straw-chopping technologies. The study investigated that by setting the chaff collector with the combine harvester can benefit the farmer.

Figure 2.

Wheat residue handling and management machinery [51, 52].

2.3 Sugarcane trash management

Sugarcane crop plays a significant role in the economy of Pakistan with collaboration of industrial sector and framers. It is the second largest cash crop of Pakistan [53]. The developing countries adopted manual method for sugarcane harvesting due to lake of mechanization. Sugarcane trash is becoming more available product in the field due to mechanical harvesting. However, due to the lack of labour and limited time of sowing for the next crop the sugarcane trash mostly burns on the site that produces toxic smoke. This show the need of mechanized policies for the timely sowing of next crop [54]. In Pakistan, the sugarcane trash management is the main problems arise after the harvesting of sugarcane. After manual harvesting, the trash management in the field is very difficult task for the farmers, so they burn it into the field. One of the significant concerns during sugarcane trash burning in the field is the environmental pollution and damage to soil microbes. The large amount of carbon, nitrogen, and particulate matter (PM) are the major chemical pollutants that are emitted during the trash burning. These emitted pollutants have severe effects on the composition and acidity of rainwater. Further, the emissions of mister and trace gases from the trash burning are very effective for human health [55]. Therefore, to mitigate the environmental pollution and enhance soil fertility worldwide, sugarcane trash shredding machinery is utilized to incorporate it into the field. The developed trash management machines cut sugarcane leftovers in the field trash of 120 to 150 cm long into small pieces and this practice is environment friendly. A few years ago, sugarcane farmers faced the problem of trash management of the crop. So, they adopted the conventional method for trash removal from the field and burnt the whole trash in the field. The trash contains very effective nutrients for soil fertility. During trash combustion very hazardous gases such as carbon, nitrogen, and particulate matter (PM) are emitted in the form of smoke which cause injury to human health. The burning of canes trash liberates a significant amount of carbon (CO2) and other greenhouse gases (GHGs). From the burning of cane, it is estimated that direct 10,410 kg/ha carbon emission occurred. Moreover, the 1791 kg CO2/ha is estimated from the other gases (CH4 = 467 kg CO2, CO = 1241 kg, and N2O = 830 kg CO2). The overall carbon emission from the cane burning is summed up to 12,204 kg CO2/ha. This emission is about 37% of the total GHGs of cane production in the farm [56].

Many researchers and industrialists designed and developed new machinery for sugarcane trash handling. Ahmad et al., [57] was designed and developed sugar can trash management machinery to control the environmental pollution and increase the soil fertility. Mukesh & Rani [58] conducted a research study to evaluate the performance evaluation of sugarcane trash management and handling machinery. During the study sugarcane trash shredder cum-chopper machine was investigated for trash management. Nikam [59] developed tractor operated sugarcane trash shredder machinery to manage the field trash. The study concluded that the developed sugarcane trash crusher would be more affordable and suitable for small and medium farmers. Moreover, this machine would be the cheapest option of the sugarcane harvesters now on the market and would result in less sugarcane degradation during storage. Singh et al., [60] worked on the ratoon management machine that was operated with tractor PTO mechanism. That was equipped with stubble-shaving serrated blades mounted on a disc, and two tillage discs for off-barring. The working capacity of the machine was 0.28 ha h⁻¹ at the forward speed of 0.67 m/s. Figure 3 represents the different sugarcane trash management machinery. In order to more effectively reuse waste by shredding and incorporating of sugarcane trash into the soil, particularly in ratoon crops without harming the crop, the tractor-operated two-row rotational sugarcane field shredder by Krishnan & Jayashree, [61]. The developed unit has two rotary members with swinging-type blades to cut the trash.

Figure 3.

Sugarcane residue handling and management machinery [57, 58].

2.4 Cotton stalk management

In Pakistan cotton is the most significant cash crop with high economic impact. In the year 2017–2018, approximately 2699 Mha area cultivated with the cotton cop with annually 11,935 thousand bales production [62]. Due to the large area of cultivation the residue produce in the bulk amount from the field. During the last few years, cotton became non-profitable for farmers due to the attack of pest/disease on cotton crop resulting in low yield and high input cost. The farmers even could not meet their actual expenses [63]. Moreover, mostly in the rural areas not enough energy sources, and cotton sticks are used as burning fuel for cooking and heating purposes. This activity leads to environmental problems such as CO2 and NOx emissions, as well as allowing the pink bollworm to finish its life cycle [64]. Since pulling and gathering the cotton stalks by hand is a time-consuming and laborious process, researchers have worked to create tools and strategies to manage it in the field.

Yumak & Evcim, [65] developed a two row cotton stalk pulling machine and conducted a study for its performance evaluation. The working efficiency of the developed machine was 9.2 ha/hr. by pull the cotton sticks from the field with the 95% efficiency. Gangade et al., [66] conducted a comparative research study of cotton stalk removal tractor operated uprooter, tractor operated slasher, and a tractor-drawn v-blade machine to investigate their working efficiencies for cotton sticks removal from the fied. The outcomes of the study concluded that the working efficiencies of the following machines were 80%, 100%, and 99%, respectively. Sheikh [67] developed a cotton stalk digger that consists of two digging units. The cutting length of the stick digger blade was 0.4 m in length. Ramadan [68] developed a prototype for the for management of the cotton sticks and perform field study to evaluate its working efficiency. The working efficiency with the tilt angle of blade was 45° at the 18.9 m/s rotating speed of under the 19% moisture content. A tractor-drawn cotton stalk puller-cum-chipper was developed by Murugesan et al., [69]. The conduccted study use the rigs test to measure the force requirment for to uproot the cotton stick from the field. Gadir [70] developed a cutting discs base cotton sticks puller machine. The disc for cutting the cotton sticks arrange in the series combination with equal spacing. The implement mounted on the tractor by three pin linkage. According to the findings, the machine worked its maximum (94%) at tilt angles of 30 degrees and rake angles of 20 degrees. It was discovered that 2.8 km/h was the ideal working speed for cotton stalk pulling. Akhtar et al., [71] was designed and developed cotton stalk puller shredder to control the pink boll warm which produces due to cotton stalk trash. The machine tested at three engine speeds and three levels of forward ground speed. A finite element analysis of parts of the cotton stalk puller shredder was performed for the purpose of improving the machine’s efficiency. Figure 4 shows the various cotton stalk handling machinery. Faisal et al., [63] was design and developed the cotton ball stripper to manage the cotton ball from the cotton stalks.

Figure 4.

Cotton stalk residue handling and management machinery [70, 71, 72].

3. Residue management for soil health

Currently, the extensive agriculture attracted much attention and depends on the inputs i.e., machinery, labor. In modern agriculture, farmers use the intensive agriculture to maximize their production by employing the crop rotation. Furthermore, the soil fertility is managed by properly maintain the crop residues. The crop residue management provides the soil surface cover, minimizing soil erosion and protect the soil form the climate effect [8]. Additionally, crop residue manages the physical, biological and chemical process within the soil [73]. If the soil is enriched with the crop residue which ultimately turns into the organic matter boosts the soil fertility and crop production. In contrast, still the crop residue is considered as the waste material due to its less economical value [74]. Crop residues, on the other hand, provide a number of possible pathways for nutrient recycling, including carbon sequestration in soil [8]. The physical, chemical, and biological characteristics of the soil, such as its structure, infiltration rate, plant water availability, nutrient cycling, cation exchange capacity, and species richness of the soil organisms are all improved by the retention of crop residues [22]. Crop residues affect the physical properties of the soil by improving the soil texture, total porosity, and decreasing the bulk density [75]. The chemical properties is also greatly influence the chemical properties i.e., pH, low buffering capacity. [75]. Figure 5 illustrates the effect of the crop residue cycle on soil condition Pan et al., [75] conducted a one month’s incubation experiment to investigate the ameliorating effects on an acidic ultimo with four crop straw decayed products (SDPs), and the results showed that the soil pH increased by 55–75% [77]. Crop residue could potentially increase the organic, carbon, nitrogen, phosphorus, and potassium concentration in the soil. The author conducted the research and concluded that by addition of the straw and partial fertilizers significantly enhances the soil nitrogen up to 20 cm and enhances the of 64% soil fertility cycle [78].

Figure 5.

Illustration of crop residue cycle on soil health profile [76].

4. Residue management for crop production

Crop residue incorporation is important aspect for the environment friendly agriculture. Moreover, crop residue return can improve crop quality and yields [79]. The meta-analysis was conducted to investigate the effect crop residue mulching on the production quantity [80, 81, 82]. Though the number of advantages of the crop residue, but some researcher also investigated that few negative impact of the crop residue incorporation on the soil. It disturbs the soil CN ratio [83] which ultimately results in loss of the crop yield [84]. So, in by-product of cereals, straw mulch can enhance a variety of soil texture and crop yield [85].

Aslam et al., [86] studied the impact of different organic mulch and nitrogen sources on wheat crop productivity. As a consequence of these findings, it was concluded that sorghum straw mulch and N in the form of calcium ammonium nitrate can successfully boost wheat productivity in semi-arid locations. The framework of crop residue effect on the crop production is shown in Figure 6. Reddy et al., [88] investigated the effect of crop residue on the crop yield enhancement. Mohammad et al., [89] conducted the research study to investigate the effect of tillage and crop residue rotation on the wheat productivity.

Figure 6.

Framework of crop residue effect on crop production [87].

5. Residue management for environment protection

The highest portion of greenhouse gas emissions from agriculture is related to emissions from arable soils (5.27%), followed by emissions from animal digestive fermentation (3.21%) and emissions from the use of livestock manure (1.58%) [90]. The adoption of precision farming on a large scale, the cultivation of crops with high carbon sequestration potential, such as energy crops, and grassland management, which offers the potential to store huge amounts of carbon in the soil, and the reforesting of agricultural land are actions that should be taken to reduce greenhouse gas emissions from agricultural practices [91]. Farmers are forced to burn the residue as a result of various socioeconomic, administrative, technical, and commercial issues, which causes a number of problems for the ecosystem [92]. In Asia, where rice is preferred over other crops, residue burning is substantially higher than on other continents. This is also true of India, where residue burning is 30% higher than in China (mainland) and 93% higher than in Pakistan [93]. Every single living organism in this area is negatively affected by residual burning. Burning residue has an extremely negative impact on soil health because it causes nitrogen (N) to be converted to nitrate (NO ⁻³) and organic matter to be lost as carbon dioxide (CO2) [92]. The agro-friendly earthworm and other microorganisms in the topsoil are also destroyed when crop residues are burned on site. Moreover, up to 80% and 90%, respectively, of the bacterial and fungal activity is reduced, while up to 65% of the microbial biomass is decreased [94]. Figure 7 presents that the crop residue management has the protentional to use conservation agriculture, for live stoke use and energy purpose.

Figure 7.

Residue management protentional for various sectors [92].

Therefore, academia conducted research studies to control the burning of crop residues to save the greenhouse gas emission and other toxic gases. Malhi et al., [95] studied the effect of tillage and residue management effect on crop yield and greenhouse gas emission. Ashraf et al., [96] studied the carbon emission estimation from rice and wheat cropping. Maucieri et al., [97] provided the meta-analysis on the crop residue management with different tillage systems to control the environmental pollution. The studies find out that the crop residue management in the field have a significant effect on both agriculture and environmental health.

6. Conclusion

Crop residue management and handling in the field is current focus of the conservational agriculture. This study aims to explore solutions for crop residue management and assess the effectiveness of available machinery for handling crop residue. This study has been thoroughly examined the performance of various types of machinery used for collecting and handling agricultural residue which concluded especially, at higher moisture content could be the best condition to chop the crop stubbles after harvesting. The literature of the study concluded that the use of machinery for residue management saves the labore requirement and timely sow the next crop that enhance the crop production. Moreover, the residue incorporation into the soil improves the soil health, reduce greenhouse gas emissions, and save environmental pollution. In addition, the performance of these machines depends on various factors such as fuel consumption, chopping capacity, and moisture content of soil and trash. This study provides the guidelines to the researchers and industrial stallholders should be work on small-scale trash management machinery.