Introduction
Crops play a very significant role in changing environment. Crop is the man-made culture involving biological and non-biological activities. Probably it is the product of human’s first biased act on the virgin earth. The crop is the man’s day-to-day needs obtaining from a limited source, utilizing merit, labor and natural resources to ensure the continuous supply regenerating as per choice and requirement. It may be for their direct, indirect, primary, secondary and tertiary purposes, e.g. food, fodder, cash crop, medicinal, fiber, forest, agriculture, horticulture, aquatic and marine crops etc.
The word “CROP” can be analyzed as follows:
‘C’ for Colonization, Civilization, Culture and Cultivation.
‘R’ for Regeneration, Reproduction, Re-growth, and Recycling.
‘O’ for Organism, Organization, Operation and Optimization.
‘P’ for Production, Processing, Preservation and Programming.
As a natural phenomenon, the population increases and colonizes under suitable conditions depending on the adaptability and availability of food and shelter. As the size of the population increases, the exploitation zone also enlarges or they migrate to other places. Nomadic life passed in the early ages through exploitation and migration. With the beginning of civilization man first started to culture and grow their desired things suppressing or eliminating the undesired ones from their surrounding environment.
Unlike other organisms, man has special demands and better adaptability since they possessed wisdom and is superior to others. Therefore, all creation of the universe is meant for the goodness of mankind. Thus man started cultivation of their required things, the crops. For cropping, physical organs were used, and then tools and equipment were developed. They learned to organize, adopted farming techniques utilizing their knowledge. From the beginning of civilization, they felt the necessities of easily available sources for food and shelter i.e. the primary needs for their survival. For that reason, they chose plants that regenerate easily; grow and re-produce quickly to meet immediate demand. Domestication of animals was started simultaneously and they selected according to their suitability in order to use for food, shelter, and protection in abnormal situations (heat, cold even in unfavorable conditions). Crops thus selected are easily utilizable, the whole biomass is re-cyclable through plants, animals, microbes, fire or other agents including human activities. The man also learned to rotate crops to conserve or return nutrients to the soil and balance the soil nutrients. To retain fertility, mixed or intercropping with legumes, symbiotic mycorrhiza, blue-green algae, Azolla, etc. is utilized.
Classification of Crops
Crops can be divided into four groups: Group 1: Primary crops: Those are directly related to human’s primary needs such as food, shelter, and protection, e.g. food, fibers, and timber etc. Group 2: Secondary Crops: Those are directly involved with the production of the primary crops, e.g. Cattle fodders and feeds, legumes or green crops, etc.Group 3: Tertiary crops: Crops grow for anticipatory purposes i.e. flavoring agents spices and cardamoms, betel nuts, cosmetics, beverages, and narcotics, etc.Group 4: Support crops: Crops that are used for processing of other crops or products (food, fiber, etc.) e.g. yeast, tannin, lubricants, and gums, etc. Man chose their needs with high yield evolved techniques for processing and also for preservation for transportation and for future use. Programs are made considering their growth, adaptability, and climatic and spatial conditions. Thus crop is something, which is directly related to the size of the population and their direct and indirect or demand or choice. American Prairie, African and Asian Savannahs, equatorial, tropical and subtropical forests, hills, lakes, ditches, and water bodies have already brought under human cropping culture. Although civilization started on the alluvial plains of Mesopotamia, Nile, Ganges, and the Yangtze but man’s needs crossed the boundaries of deserts, forests, and mountains and offshore increasing the exploitation zones by cropping. Thus cropping is the root of all changes in the environment. Therefore, cropping can significantly share in the conservation of nature through proper knowledge in production, processing, distribution, and optimization through balancing production and population growth of human beings. Increased productivity can also be achieved through diversification, changing habits and habitat, and increasing exploitation zone, utilizing sea resources. Quick recycling of the ingredients through the food chain, reproduction, growth, consumption, and decomposition involving more species in the cultural activities of forest and marine products. Cultivation of multipurpose crops, shade-loving aroids, root crops, tubers, corms, creepers and climbers with symbiotic or commensally behaviors, should be encouraged. Decomposes of garbage, wastage, excreta, and sludge, etc. from the cities, should return back to the cropping land as compost. The landscape should be maintained without hampering the water flow of the rivers, streams, and flood plains, etc. during the construction of roads, rails, highways, bridges, dams, and embankments, etc. The navigation system should be improved for quick transportation and communication instead of roads and bridges. Plainland should be planted with crops, e.g. vegetables, fruit, root and multipurpose timber crops etc. For retention and balancing of soil nutrients and to increase porosity crop rotation must be done periodically. It will also help to control harmful pathogens. Hunter and hunted theory is equally applicable to cropping culture. The man should be considered as one of the members of the food cycle. Forest crops should also be considered as other crops limiting their cycle for the use of mankind. Cropping cycle: It is one of the most important factors for resource conservation. Long rotation crops can cause imbalance to meet the increasing demand of the growing population. To solve this problem, their use can be endured long-lasting or minimizing the wastage through appropriate technology. Broad-spectrum use of limited quantity material should be ensured and production and utilization must be run parallel without any gap in the cropping cycle. Crops can also be classified on the basis of their growing environment depending on their basic needs: nutrients, water, air, light, and temperature; their availability and intensity, the association of other lives and agencies for the food chain, reproduction (breeding and pollination), protection, decomposition and degradation for nutrient recycling. Land crops.g. Erective, Creepers, Climbers, and Subsoil or Ground crops, etc. Aquatic crop e.g. Floating and Submerged: Azolla, Water hyacinths and Kelp, etc.
Surface crop e.g. Cattle Fodder and Poultry Feed
Marshland crop e.g. Makhna (Euryale) and Sedge etc.
Aerial crop e.g. Orchids and Vanilla etc. According to regional distribution crop can also be classified as follows:Tropical: Humid and Xerophytes Temperate: Alpine and SavannahArctic
According to light intensity Photonutral Photoperiodic; High light intensity, partial shade-loving, Shade-loving and Dark dweller. According to the cropping period crops can also be classified into Annual, Biennial, Perennial, Seasonal, Periodical, Diurnal etc.
Crops’ effect on the environment
Although the industrial revolution through the utilization of fossil fuel and minerals from the nineteenth century played a very significant role in changing global climatic change and affected the lives the crop has taken a silent part in the total changing of the environment. For cropping, forests, wetlands, and water bodies were cultivated as per man’s desire and need. Many species are facing extinction for the use of chemical fertilizer and pesticides. Although hybridization and clonal propagation have increased production and productivity but affected the beauty of natural diversity. Cropping culture: Creation of habitat and to fulfil the required basic needs e.g. irrigation and use of sub-soil water, terracing, manuring, weeding, waste disposal, etc. are the important factors those influence the surroundings. For instance, hills are terraced, water bodies are converted to marshland by landfilling, streams and rivers are diverting and canals are dug for creating new land for cropping. Hybridization and mutation for high yielding crops are done through genetic engineering and irradiation narrowing the selection and propagation wide range of species group. Crop related industries: Cultural methods, chemical fertilizer, pesticides, harvesting, processing, transportation, storage, and preservation, etc. their mechanization and motorization, added industrial effect on climate change.
Selection of crop
All creations are meant for the help of mankind. The man should ensure their proper and appropriate use. It should also be remembered that nothing in this world is uncalled for. Therefore, man has got the right to select his required things for his use on the basis of merit, but not indiscriminately. The selection of crops started from the prehistoric age. Easy cultivation, high yield, simple handling and preservation, and easy transportation are basic criteria of crop selection. However, some more points are suggested for wider adoption and less effect on the environment, a continuation of the beauty of the diversified nature and to prevent from the man-made effect on quick climatic change. Cosmopolitan nature: Crop should be selected which is widely adaptable in different ecological regions.Genetic diversity: Large numbers of varieties, clones, and strains of crops with genetic diversities, adaptability, and suitability in a wide range of environmental variation is essential. Heterogeneity: Cross-pollination or heterogenic behavior is more adaptable in a variable environment.Propagation: Self-grown, capable of propagating asexual and sexually are more resistant to withstand in adverse conditions.Synergism: Synergistic behavior with other species and micro-flora of the same habitat is preferred.Diversification: Crop must not be diversified only on the basic requirement like nutrients, water, air, light, and temperature but natural habitat should be considered. Cropping should not be done after creating a new environment at a different site, which can change the ecosystem. Studying the indigenous practices of utilization, broad-spectrum cropping with a large number of species according to habitat should be brought under cultivation. Yield and productivity must be considered on their multiple activities but not on the demand and high price of a specific crop. Crop rotation: Sequential rotation of crops, their timings, and cropping period should be maintained with other crops suitable to that habitat. Weeds and predators: Regeneration of weeds and predators must not be blocked but they should be considered as members of the food chain and source of biomass and should be utilized for the need of human beings, directly or indirectly. Landscape: No cultivation should be done disturbing the landscape and natural water flow. Product re-cycling: Crop buy without a prescription wastage, residual debris, corpse, and products should be re-cycled in the same type of ecological niche through the hunter-hunted and assimilation-degradation process, to balance the quantity of the basic ingredients. City wastes: Waste decomposes of the urban areas must not be dumped for landfills or into the ditches, lakes, rivers, and seas but should be returned back to its origin or hinterland as much as possible. Crop and environmental biotechnology: To meet the demand for food and other necessities for the increasing population biotechnological processes can help to solve the problems of health, agricultural industrial development, and energy production. In-depth research on crop production, bio-fertilizer, bio-fuels, basic biology, isotope, and radiation biology, and environmental biotechnology for industrial and agricultural applications can mitigate the present status of global climate change.
Conclusion
Cropping culture has a significant influence on changing the environment. Careful management of crops and recycling of ingredients through biotic, edaphic, and climatic environmental adaptability can minimize the detrimental effects of quick changes. It needs appropriate research on humans’ activities for exploitation of nature and sympathy to the creation.