It is often stated that pests will be less damaging in fields with a mixture of crops than in fields with a single crop, also known as monocultures. Crop diversification and household food security status. Fewer crop species are feeding the world than 50 years ago, raising concerns about the resilience and nutritional value of the global food system, a study says. Agriculture report 2017 biological diversity in agricultural. The vector z i contains a set of variables thought to influence crop diversification. For example, crop diversity was reported to sustain soil quality, to buffer yield variance against adverse weather events and to substitute fertilizer use while maintaining economic competitiveness 24. Brief outlines of the two types of diversity indices of biodiversity are discussed in this article. In many parts of the world, traditional crop varieties landraces in the sense of harlan 5. The harvested production of cereals including rice in the eu was 295. Count perennial crops, such as, alfalfa andor grass as occurring once in a rotation even though they may occupy more than one year. Status provides the current state of agrobiodiversity using 7 indicators that measure diversity of crops, crop wild relatives, fish, livestock and pollinators at different levels varietal and. The role of crop diversification in improving household food.
Web of science, geobase, agris, agricola, greenfile to identify studies reporting the impacts of crop diversity and crop species on the biological diversity of fauna, flora and microbes in agricultural landscapes. Averaged across all sampling methods and years, the weed diversity index of the organic green manure rotation was 1. Agricultural production crops statistics explained. Characteristic domestication bottlenecks were also detected with chloroplast microsatellites. Count the number of crops since the same type of crop is used in the rotation for each crop not to exceed 4. If every person in the world donated just 12 cents, the crop. The recent experience in asia, particularly southeast asia, middle east and north africa indicates that policy. The conservation planner should develop alternative combinations of crops and field operations for the producer to consider.
Sustainability free fulltext crop diversity and common. Maize is the staple food crop, and as such, the majority of farmers grow it. Crop diversification a strategy to improve agricultural. Where p i is the relative abundance of species i, s is the total number of species present and ln is the natural log. The role of crop diversification in improving household. Yet each time a crop fails we look to these fields around the world for new varieties, new genes, new enemies of pests, new mutualists of our crops.
Ensuring food security, adapting to climate change, reducing environmental degradation, protecting nutritional security, reducing poverty and ensuring sustainable agriculture are just six reasons why it matters to conserve crop diversity. Increased weed diversity, density and aboveground biomass. Crop diversification index was worked out using tribal. National food production stabilized by crop diversity nature. Crop diversification and livelihoods of smallholder. Abundance and diversity of soil macrofauna in native forest. Conserving crop diversity is the first and most crucial step to ensuring food security. Pdf crop diversity for yield increase researchgate. Members of the crop wild relatives project from the crop trust joined their research partners in nepal on an expedition to collect wild. The case studies include detailed analysis of traditional. News out of harvard suggests that not only will climate change affect how food is grown, but it will also lower the nutrition levels of. For example, crop diversity is not directly considered in the sci estimates.
Global crop diversity trust crop diversity reporting tool. Jun 19, 2019 af, magnitude of the change in national yield stability as dependent on effective crop group diversity a and effective species diversity d, precipitation instability b, e and irrigation. Understanding crop genetic diversity under modern plant. Normalized difference vegetation index ndvi how ndvi works live green plants absorb solar radiation in the photosynthetically active radiation par spectral region, which they use as a source of energy in the process of photosynthesis. Status provides the current state of agrobiodiversity using 7 indicators that measure diversity of crops, crop wild relatives, fish, livestock and pollinators at different levels varietal and genetic, species, farm, landscape, ecosystem. The diversity of the soil macrofauna community was calculated by the shannon diversity index h for each lus. Erosion values must be adjusted for each alternative as a new sci is generated. Crop diversity and stability of revenue on farms in central. Aug 18, 2014 crop diversity is key to agricultural climate adaptation. Ensuring the conservation and availability of crop diversity for food security worldwide.
The authors discuss the economics of managing crop diversity onfarm in the context of crop variety attribute preferences, farmers perception of agrobiodiversity loss, and value addition and marketing of the products of traditional crop varieties. Shannonwiener index was used to calculate crop diversity because this index determines the shift of both crop species richness and abundance. Pi proportion of jlh crop entropy index is regarded as an in verse measure of crop concentration having logarithmic character. Aug 06, 2015 maximizing crop yield while at the same time minimizing crop failure for sustainable agriculture requires a better understanding of the impacts of plant breeding on crop genetic diversity. Lets use r to calculate h for the two communities in the example above. Along with this increased interest has come questions about the changing roles of the public and private sectors in collecting, conserving, and. Crop diversity is the variance in genetic and phenotypic characteristics of plants used in agriculture.
Definition and measurement of crop diversity for economic. I recommend to farmers who cant pencil out a third or fourth crop to try cover crops, says wick. Species composition and diversity index values for cover crop polycultures. With the support of individuals, the private sector, foundations, and the governments of the world, we can save crop diversity forever. A diversity index also called phylogenetic or simpsons diversity index is a quantitative measure that reflects how many different types such as species there are in a dataset a community and that can simultaneously take into account the phylogenetic relations among the individuals distributed among those types, such as richness, divergence or evenness. A modified diversity index and its application to crop. Moreover, the average simpson index diversity at the farm level is 0. Species diversity of the weed seedbank and the aboveground weed community, as determined by the shannon diversity index, were greatest in the organic green manure rotation. A global perspective of the richness and evenness of traditional crop. In this case, we created a crop diversification index 1 measuring the extent of crop diversification for each smallholder farmer which we then use to create the binary variable cd equals 1 if the crop diversification score is greater than 0 implying some diversification by smallholder farmer and 0 otherwise. Pandey and others published crop species diversity. Dominance indices are weighted toward the abundance of the commonest species.
Time series ndvi imagery is generated from the processing of sentinel2a msi l1c product. More than 70 percent of indias population lives in rural areas where the main occupation is agriculture. Aug 26, 2015 crop diversity encs at the national level increased from from1978 to 1987 fig 2. The north dakota state university extension soil health specialist encourages farmers to take a systems approach to manage. Hazra agriculture commissioner, department of agriculture and cooperation, ministry of agriculture, krishi bhawan, new delhi, india. Crop species diversity changes in the united states. Diversity index for crop rotations avoid conflicts among seeding and harvest times of different crops for example. Over the past 50 years, there has been a major decline in two components of crop diversity. The us has only 10% of the crop variety found in the worlds plant gene banks in its own collections soybean does not originate from brazil, yet brazil has the second largest production of soybean in the world wheat variety veery. Mar 03, 2014 fewer crop species are feeding the world than 50 years ago, raising concerns about the resilience and nutritional value of the global food system, a study says. In this country, the agricultural sector is dominated by smallholder farming and rainfed food production systems that are facing increasing challenges from land degradation and declining soil fertility. Crop breeding programs have increasingly focused on international needs. All major food crops, the staple crops grown and consumed by the vast majority of the worlds population, have their origins in the tropics and subtropics of asia, africa and latin america.
The relative frequency of the main groups in all lus was also. Fasching, state agronomist background historically, crop rotations were much more diverse than they are presently. A modified diversity index and its application to crop diversity in assam, india premananda bharatia, utpal kumar deb and manoranjan palc abiological anthropology unit, indian statistical institute, 203 bt road, kolkata 700108, india bdepartment of economics,northeastern hill university, shillong, 793022, meghalaya, india ceconomic research unit, indian statistical institute, 203 bt road. A widely used dominance index is simpsons diversity index. These indices provide a clear idea about the changing trajectory of the agricultural sector and cropping pattern in the state.
Its a way producers can get more diversity, and its a great way to start. Another common method for measuring the crop diversification is to count the number of crop grown by farmer. The period since 1970 has seen a growth in germplasm collection and conservation. Sections of the book explore the conservation of crop genetic resources and their diversity both ex situ and in situ, the impacts of diversity on the yield and yield stability of a crop outside the experiment station, and the effects of policies on the utilization of these resources by farmers and scientists. The six key areas where crop diversity is essential. This paper concerns the role of crop diversification in improving household food security in central malawi. Fred werneck, christine negra, coosje hoogendoorn, gianpiero menza.
With the advent of modern agricultural technology, especially during the period of the green revolution in the late sixties and early seventies, there is a continuous surge for diversified agriculture in terms of crops, primarily on economic considerations. Crop diversity decline threatens food security bbc news. Margalef and simpson indices4 as a measure of crop diversity. Abundance and diversity of soil macrofauna in native. The diversity indices were estimated using the vegan package for community ecology oksanen et al. Mar 21, 2018 this paper concerns the role of crop diversification in improving household food security in central malawi. This paper presents the application of ndvi technique for extracting net sown cropped area of major crops cultivated during the winter season octobermarch and calculation of crop diversity index at nyaya panchayat level in bara tehsil of allahabad district.
Mar 30, 2017 yet each time a crop fails we look to these fields around the world for new varieties, new genes, new enemies of pests, new mutualists of our crops. Cereal harvest in the eu sharply lower due to widespread drought conditions in central and northern member states. Crop diversity and land simplification effects on pest. This index is borrowed from information science, and is calculated as follows. Dwayne beck, sdsu dakota lakes research farm, pierre sd in the publication the power behind crop rotations. Crop diversity and land simplification effects on pest damage. Over the past 12,000 years, farmers selected and domesticated all major food crops on which humans depend today. Crop diversity and stability of revenue on farms in. Pdf a global perspective of the richness and evenness of. Many commonly used indices are drawn from ecological and agronomic literature and are based on some type of distance metric. Normalized difference vegetation index ndvi analysis for. There are several ways to measure crops diversification, and the most important include herfindahl index, simpson diversity index, ogive index, margalef index, shannon index, bergerparker index and entropy index. Scientific name, common name, phenological niche, nitrogen n acquisition strategy, and trait values for cover crop species.
Abbey wick sees the healthiest soils when there are three or more crops in rotation. The crop diversification is also taking place due to governmental policies, thrust on some crops, market reforms, infrastructure development, government subsidies, certain other price related support mechanisms, higher profitability and stability in production also induces crop diversification. Crop diversity is key to agricultural climate adaptation. Crop diversity is an important part of agrobiodiversity and is related to ecosystem services provided by agroecosystems. Pdf varietal data from 27 crop species from five continents were drawn together to determine overall trends in crop varietal diversity on farm find, read. Increase variety in crop rotation to boost the overall health of your field. A modified diversity index and its application to crop diversity in assam, india premananda bharatia, utpal kumar deb and manoranjan palc abiological anthropology unit, indian statistical institute, 203 bt road, kolkata 700108, india. Pdf relationships among rotational intensity, crop. In addition, non crop plants such as weeds, cover crops, and habitat plantings can be combined in space and time to influence numbers of pest and beneficial arthropods on the main crop. In addition, noncrop plants such as weeds, cover crops, and habitat plantings can be combined in space and time to influence numbers of pest and beneficial arthropods on the main crop. For example, a county producing 10 crops with each crop accounting for 10% of the acreage would have an. The closer the diversity index is to 1, the more diverse and healthy it is. Relationships among rotational intensity, crop diversity index, land utilization index and yield efficiency in biointensive and conventional farming systems article pdf available january. However, since 1987, crop diversity has decreased and crop diversity in 2012 was significantly lower than in 1978.
Encs is an easily interpreted index of crop species diversity, with a value representing an estimate of the number of crops dominating production in a particular county. The activity illustrates how to use math to calculate the diversity index of a selected habitat. Chapter 1 introduction crop diversification has emerged an important alternative to attain the objectives of output growth, employment generation and natural resources sustainability in the developing countries. Fao estimates that 75 per cent of crop diversity was lost between 1900 and 2000. Ndvi is calculated from the visible and nearinfrared light reflected by vegetation. In every province, the annual crop diversity was calculated from 1987 to 2012. Crop diversity in 1992 was similar to 1978 but by 2012, crop diversity was significantly lower than any other census period fig 2. Functional diversity in cover crop polycultures increases. Aug 22, 2017 however, that doesnt mean farmers shouldnt be trying to increase crop diversity, says wick. This measure is applied on acreage proportion to measure the crop diversification. Statistics on crop production are shown both at an aggregated level and for over 100 different crop products. We used shannon diversity indices expressed as effective number of crop species encs to quantify crop diversity.
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