Crops play a very significant rule 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. Crop is the man’s day-to-day needs obtaining from 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, population increases and colonizes under suitable condition depending on the adaptability and availability of food and shelter. As the size of the population increases, 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 demand and better adaptability since they possessed wisdom and is superior to others. Therefore, all creation of the universe is meant for the goodness of the mankind. Thus man started cultivation of their required things, the crops. For cropping, physical organs were used, and then tools and equipments were developed.They learned to organize, adopted farming techniques utilizing their knowledge. From the beginning of the 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 those 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. Man also learnt to rotate crops to conserve or return nutrients to the soil and balance the soil nutrients. To retain the fertility, mixed or intercropping with legumes, symbiotic mycorrhiza, blue green algae, azolla etc. is utilized.
Classification of Crops
Crops can be divided in to four groups:Group 1: Primary crops: Those are directly related with 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 primary crop, e.g. Cattle, fodders, feeds, legumes or green crops etc.Group 3: Tertiary crops: Crops grow for anticipatory purpose i.e. flavoring agents spices and cardamoms, betel nuts, cosmetics, beverages and narcotics etc.Group 4: Support crops: Crops those 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 with the size of population and their direct and indirect or demand or choice. American Prairie, African and Asian Savannahs, equatorial, tropical and sub tropical 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 Yangtze but man’s needs crossed the boundaries of deserts, forests, and mountains and off shores increasing the exploitation zones by cropping.Thus cropping is the root of all changes of the environment. Therefore, cropping can significantly share in 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 habit and habitat and increasing exploitation zone, utilizing sea resources.Quick recycling the ingredients through food chain, reproduction, growth, consumption and decomposition involving more species in 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.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. Navigation system should be improved for quick transportation and communication instead of roads and bridges. Plain land 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 controlling harmful pathogens.Hunter and hunted theory is equally applicable for cropping culture. 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 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, association of other lives and agencies for food chain, reproduction (breeding and pollination), protection, decomposition and degradation for nutrient recycling.Land crope.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 and Poultry
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 intensityPhotonutralPhotoperiodicHigh light intensityPartial Shade lovingShade loving3. Dark dwellerAccording to cropping period crops can also be classed into:AnnualBiannualSeasonalPeriodicalDiurnal
Crops’ effect on environment
Although industrial revolution through utilization of fossil fuel and minerals from the nineteenth century played a very significant role in changing global climatic change and affected the lives but crop has taken a silent part on 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 fulfill 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 land filling, 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 affect on climate change.
Selection of crop
All creations are meant for the help of mankind. 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. Selection of crop 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 affect on the environment, continuation of beauty of the diversified nature and to prevent from man made affect 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 wide range of environmental variation is essential. Heterogeneity: Cross-pollination or heterorgenic behavior is more adaptable in variable environment.Propagation: Self-grown, capable of propagate asexual and sexually are more resistant to withstand in adverse condition.Synergism: Synergistic behavior with other species and micro-flora of the same habitat are 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 new environment at different site, which can change the ecosystem. Studying the indigenous practices of utilization, broad spectrum cropping with large number of species in 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 food chain and source of biomass and should be utilized for the need of human being, 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 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 land fill or to the ditches, lakes, rivers and seas but should be return back to its origin or hinterland as much as possible.Crop and environmental bio-technology: To meet the demand of food and other necessities for the increasing population bio-technological 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 bio-technology for industrial and agricultural applications can mitigate the present status of global climate change.
Cropping culture has 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.
Latest posts by Dr. Mohammed Ataur Rahman (see all)
- আবর্তনে বিবর্তন - October 26, 2017
- আবর্তনে বিবর্তন - October 24, 2017
- Women Empowerment to Lead Change- Bangladesh Perspective - February 27, 2017