Monday, May 21, 2012

Sugarcane Vulnerability Map During Extreme Weather Condition in Tarlac, Philippines






Introduction

Precision agriculture is an agricultural system that has the potential of dramatically changing agriculture in this 21st century. It lends itself to most agricultural applications and can be implemented at whatever levels are required. Precision agriculture is based on information technology, which enables the producer to collect information and data for better decision making. Also, it is a pro-active approach that reduces some of the risks and variables common to agriculture. Precision agriculture is considered a concept, management strategy, and even a philosophy that is environmentally sound and is an integral part in sustaining natural resources. The concept of precision agriculture offers the promise of increasing productivity while decreasing production cost and minimizing environmental impacts. (Michael Rasher).
By incorporating Global Positioning System (GPS) into standard farming practices, farmers, researchers, and consultants have been able to improve the precision of existing agronomic management activities by implementing them at a subfield scale. Perhaps the most influential development to expedite technology transfer to agriculture has been the development of GPS. Precision farming and associated variable rate technologies have been the result. Potentially, factors that influence crop productivity can be identified, mapped, and used to provide an implemented solution.

The increased efficiency and profitability that the proper application of technology can provide has made precision agriculture the hottest developing area within traditional agriculture. Modern farming is about optimizing agricultural production. In this aspect, nothing has changed for thousands of years. Farmers have always been aware of striking a balance when applying inputs that increase crop yields but incur costs and reduce the eventual value of their harvests. Ever increasing acceptance of information technology in everyday life has had an impact on farming, and this will only grow with increased accessibility.

Preserving the environment, managing assets, constant overproduction with low prices, changing government subsidies, biotechnology, and intense global competition are reasons agricultural professionals are using Geographic Information System (GIS) tech-nology. With increased awareness of geospatial technologies and its role in society, agriculture has and must continue to embrace GIS to adapt to these changing circumstances.

The Philippine Sugarcane Industry is being regulated through Sugar Regulatory Administration. The primary goal of the agency is to have a balance on the sugar prices where the sugar planters are making profit and also the sugar consumers are buying on a reasonable price. The pricing is based on the supply that will be available in the market. But the challenge is to have an accurate estimate on the production of sugar in the Philippines months before the actual milling operation will start.

Crop yield is one of the major factors which influence the productivity of any agriculture system. At present, the agency is facing many serious issues related to existing crop yield forecasting system. One of them is the time lag between the crop harvest and its final yield estimation. This time lag had caused heavy financial losses many times in the past. There is a need of a system which can seek a possibility to strengthen the existing yield forecast/estimation system. This will further ensure correct decision making in view of sugar regulation.

The Philippine Sugarcane Industry is divided into smaller units called Mill Districts, which are specific locations where sugar mills are. In Luzon, there are six (6) Mill Districts and one of these is the Tarlac Mill District. At present (Crop Year 2011-2012) Tarlac Mill District has an area of 15,700 ha planted to sugarcane. This are is estimated by GPS area survey, launched and funded by CAT management (Sugar Mill Company). The investment in GPS technology for area mapping has allowed our planters to obtain accurate field area measurements which they can utilize as a basis for an efficient use of farm inputs. Five (5) units of handheld GPS device were used, with an additional unit from the SRA-Extension Division.

Better and more accurate indicator for the district¡¦s productivity is hinged on a credible area estimate. The baseline data which dictates the performance of each crop year is the reliable area estimate. Recognizing the importance of productivity gage of the district, the need for more accurate sugarcane area must be first confirmed.

The sugar industry is gradually adopting and exploiting the full potential of GIS and developing awareness of the GPS capabilities. With the changing climate, certain adjustments and timely decisions are very vital in the field. Agricultural risks are inevitable; they can either make better or worse farmers. Technological tools are now within reach, which can aid in decision making. GPS mapping is the very first step towards precision agriculture. Investment in GPS technology for field boundary mapping has allowed producers to obtain
accurate field area measurements, usually resulting in a lower area than previously thought. Spatial analysis, the study of geographic features, and the relationships that exist between them, can be applied to many areas of the agriculture industry. By better understanding how features within the landscape interact, decision makers can optimize operational efficiency and improve economic returns. Regardless of scale, whether at farm field level or across an entire country analysis of crop yield information, GIS is becoming fully integrated and widely accepted for assisting government agencies to manage programs that support farmers and protect the environment. These are the areas where the Sugarcane Industry will be focusing with GIS application in the field:
- Combining agronomic and economic data sets (soil, topography, weather, farm inputs, variety performance and other site specific attributes)
- Field data management (historical data, sampling sites, fertilizer used, irrigation and drainage, factors influencing growth at different stages)
- Decision support for farm management (timing of planting and harvesting, fertilizer application, irrigation frequency, pest control, cultivation practices and others)
- Farm asset allocation (mechanization Level, available irrigation facility locations, Field input reporting, Cane Harvest pattern during normal weather condition and extreme conditions
- Crop Forecasting
- Crop damage due to flooding and drought (Effect of Climate Variability)

Statement of the Problem

Recently Tarlac Mill District was faced with a challenge of having a two consecutive low yielding crop year. One of the contributing factors is the uncalculated risks in sugarcane production is brought by Climate Variability. Timing of cultural practices seemed to be derailed with the prevailing micro climate. Challenges such as excess or inadequate rainfall, the number of Sunshine Durations (Degree Days), and changing temperatures can all lead to fluctuation on farm productivity. As a result, accuracy on crop forecasting is affected. Crop Forecasting is very important on planning and policy making. Also, the GPS data were merely for area estimation thus, the potential for further use of the data is not being exploited.

Project Objectives

1. With the aid of GIS, we can have a better understanding and analysis of the risks on certain areas that will be greatly affected by extreme weather phenomenon.
2. Crop forecast will have a higher level of accuracy and mitigation/interventions methods to minimize the losses and effect on the crop production can be implemented.
3. Crop Vulnerability map will be very useful in the assessment for crop growth that can be used as a reference in crop estimates.
Through time, these data can be used in:
- Coping and adapting agro meteorological risk
- Formulate risk management tools (decision making, policies, forecasts, etc.)
- Enhanced decision making, reducing climate risks exposures/ impacts.
- Decision making based on climate information, more accurate forecasts and estimates
- Improvement in cultural management timing (planting opportunity, fertilization,   peak of maturity during harvest).
- planning and operation for agricultural production
- pest and diseases monitoring
- Deliver a more adaptable technology in sugarcane production at specific weather condition for specific site.

Methodology

During the past years the district (Tarlac Mill District) came up with a plan that will identify the areas that will be the focus of the intensification intervention to increase the productivity. Physical environmental scanning, planter¡¦s interview on their farming experiences was done to identify the problems.
Actual Field Visits and Planter¡¦s interview
The observations were:
- Soil Analysis has never been practiced.
- Planters don¡¦t know the importance of fertilizer frequency and proper application (the losses through leaching, volatization and improper amount applied)
- Poor Land Preparation = poor ratoons
- Mostly ratoon establishment and management is a problem (Importance of stubble shaving).
- Poor timing on cultural operations.
- Poor soil condition/ deterioration especially on ¡§lahar areas¡¨.
- Lack of good varieties of sugarcane for specific soil type
- Improper cost reduction on certain cultural practices needed by the crop. (e.g. Cultivation, weeding, irrigation, land preparation)

Field Analysis

With this, certain programs have been formulated based on the need of the area. Modules or lecture materials answering their concerns will help them understand better how to increase their productivity. However, the equipping must be done on the part of CAT (milling company) fieldmen to realize and effectively/accurately deliver and monitor their planters. To attain the main goal constant visits and assistance must be done to increase the awareness and adaptability of the planters.
The whole thought of the program is to have an optimum yield at a maximum profit. Re-aligning the resources and inputs according to plant growth needs will help in achieving the main goal of increasing the level of productivity. San Pedro, Bamban Smut Infected Cubcub, Capas Patling, Capas Available resources Sta. Rosa, Concepcion SOIL SAMPLING SOIL SAMPLING
Upon the assessment and analysis of the situation and the historical data on the district, it was found out that one of the recent contributing factor on the productivity is weather (rainfall and sunshine duration) Identifying the areas that have high exposures to extreme events must be identified to focus the resources in this area and mitigate the effects of such phenomenon.
¡¨Generic¡¨ data, are those data that are also available for other mill districts, were used. And these are:
- Elevation
- Soil type
- River Proximity (that can be a threat during too much rainfall)
- GPS surveyed sugarcane areas( in Tarlac)
*for further study and analysis
   *Crop Productivity Map
   *Field Performance at Barangay Level

PROCEDURAL METHODS

First step is to identify the areas on the low lying locations and the areas on high elevations to visualize the general topography of the whole district. The data available is a raster file (DEM) and the GPS areas.
ELEVATION CLUSTERED SUGARCANE FIELD
Elevation Extraction from SRTM
- Load the SRTM (DEM raster file)
- Clip the raster data using the area bounded by the GPS areas
- Use Clip tool under the Raster Processor on the Data Management Tools
- Output: Clipped DEM
Enhancement of the DEM to visualize elevation differences on the area
- To make it more realistic, use Hillshade and under the Layers Properties use stretched Type: Standard ; Deviation n=3
- To enhance further, use Resample: Bilinear Interpolation under the Display, Properties
- To differentiate elevation ranges use Classify under the Properties tab Adjust breaks to the desired output (optional: add a contour index)
Addition of elevation data to the GPS bounded sugarcane areas
- Load Clipped DEM and GPS DATA
- Assign a centroid on each parcellary area of sugarcane
- Transfer the elevation data on the Dem to the parcellary area by using the Extract values to point under the Extraction on the Spatial Analyst tool.
Combination of the Enhanced clipped DEM and the GPS areas with elevation
- Load the Enhanced DEM and GPS areas
- With this a visual display of areas at different elevation is a very essential and useful data in analyzing the whole district

GENERALIZED SOIL MAP OF TARLAC (with sugarcane areas) LOAM CLAY SANDY

Second step is to locate the areas under the same soil type or texture to analyze the different soil classification within the sugarcane district.
SOIL MAP OF TARLAC (with sugarcane areas)

River Buffering at 1km

Third step is to analyse the river channels in case of heavy or high amounts of rainfall that could contribute or expose the sugarcane areas to flooding. A buffer of 1km is used to approximate the influence of the flooding scenario.
River channels buffered at 1km and the GPS areas Areas that has high vulnerability to river buffering at 1km

DISCUSSION AND ANALYSIS

Recently, during the months of September to October where great quantity of rainfall fills the main river channels and tributaries of Tarlac, areas laying on lower elevations were being flooded. Rainfall intensity is remarkably higher that before. Areas near these river channels are directly affected. On the other hand seepage water is eminent on the sugarcane areas though not directly affected by the flood water the excess moisture is not favourable for sugarcane. These waterlogged conditions adversely affect both cane yield and sugar recovery due to moisture stress. Especially during the La Nina occurrence, poor harvest is expected within these areas. In most of these areas, the crop experiences moisture stress during the formative phase of growth, affecting germination and tillering, thus leading to reduced stalk population and reduced initial stalk growth. Some early planted cane however; moisture stress coincides with the ground growth phase of the crop, thus affecting stalk elongation and stalk growth. While in the case of late planted crops, moisture stress affects the formative phase as well as maturity and ripening phases. Thus initial crop stand gets affected and also there could be disruption in the sugar synthesis and accumulation under severe stress during the ripening phase.

Sugarcane can withstand certain degree of moisture stress without any serious yield or quality loss as it has remarkable ability to recover and put up normal growth arc released from stress either through rainfall or irrigation. However, under severe stress the yield loss may go up to 60-70 per cent. This pose a great threat on the crop productivity.On the other hand areas with higher elevations do not have significant effect in terms of yield loss. With higher elevation, excess water will just be quickly drained out the field.

Soil Porosity

Soil texture and structure influence porosity by determining the size, number and interconnection of pores. Coarse textured soils have many large (macro) pores because of the loose arrangement of larger particles with one another. Fine-textured soils are more tightly arranged and have more small (micro) pores. Macropores in fine-textured soils exist between aggregates. Because fine-textured soils have both macro- and micropores, they generally have a greater total porosity, or sum of all pores, than coarse-textured soils. (Ann McCauley)
Soil porosity affects drainage, allowing soils to hold water for plant consumption, and draining excess water. Poor porosity facilitates erosion of soils as rainwater washes particles off the surface rather than penetrating into soil.

Clay and silt soils tend to stick together, not allowing water and air to penetrate soil structure. They have poor soil porosity and do not let water drain. Aeration is poor and many plants decline and die in these non-porous, waterlogged soils. While sandy soils drain well and have fairly good porosity, even though the spaces between the particles are small. Highly sandy soil does not hold water during heavy rains (La Nina) but the excess air in the soil can dry roots out quickly during drought (El Nino). On the other hand, loamy soils have the best porosity, which are mixtures of clay, silt and sand with organic matter. Loam holds water and nutrients, releases them to plants roots and drains excess water. Their porous nature allows rainwater penetration, reducing nutrient and mineral runoff and holds up moisture during dry conditions.

Other important bases of the analysis for soil texture: Sandy Soils „h Sandy soils drain the most quickly. They have little organic matter in them, and gardeners add compost to them before they plant. They require the most frequent amendments, both of organic matter and fertilizer, because the sand does not absorb water. The sand particles are abrasive to the organic matter added to them, breaking them down more quickly than soils with less sand. Clay Soils „h Clay soils have the least porosity. Their texture is heavy and smooth. Clay holds onto water by bonding tightly to it chemically, and is considered hydrophilic. When the moisture content of clay soils starts to dry, the soil competes with the plant roots and usually wins. As with sandy soils, adding compost or manure is a common practice to make the soils lighter so they drain faster. Clay soils normally have a high mineral content, although in alkaline conditions, the minerals may not be available to the plant roots.


CONCLUSION AND RECOMMENDATION

After the risks have been identified, crop forecasting can be improved. Yield adjustments in these areas during abnormal weather phenomenon can be predicted. The magnitude of the possible yield reduction can be analyzed using this map. Moreover, resources can now be channelled through these specific locations in order to improve the productivity at certain weather condition. Around 3,400 hectares are vulnerable during El Nino while 6,200 hectares are at high risk during La Nina. This threat is now an opportunity to enhance the farm management practices and decision making. Improvement in overall productivity of the district entails an increase in profit for sugarcane planters. The visual representation that a vulnerability map offers and the discussions that ensure after a presentation can be a major contribution to reduce the uncertainty and risks in agriculture. This will broaden the idea of each stake holder on how to decide at a particular weather risk scenario for the crop.
Vulnerability mapping begins with an accurate representation of natural features such as rivers, lakes, landforms, topography, soil type and others that can affect the growth and development of sugarcane. The vulnerability map is only part of the effort to monitor, assess and recommend certain improvements. It is also the key in attracting managers, decision makers, and farmers to adapt and cope up with the changing environment.

LA NINA Risk Mitigation Plan

  •  Proper Placement of Fertilizer

During the excessive rainfall the fertilizer applied has a high possible of being diluted in water and become unavailable to sustain the nutrients required for sugarcane growth. It is recommended to have an early fertilization schedule and a deeper fertilizer placement to anticipate nutrient losses and improve fertilizer efficiency

  •  Use high ridge furrow

On the occurrence of excessive precipitation, high ridges will facilitate drainage and also will serve as a support for the plant.


  • Construct Drainage System 
Provide drainage channels, which are deeper than the furrows along the field borders as well as within the field at regular intervals. Drainage channels are particularly important in the high rainfall areas to drain the excess water during rainy season.

EL NINO Risk Mitigation Plan



  • Deep Tillage Tillage operations through tractor drawn implements are most ideal and quick. For initial ploughing use either mould board plough or disc plough. Whenever, soil turning is desired, a mould board plough should be used. To prepare the field which permits optimal soil water air relations and optimize the rooting development of the crop. With a good rooting system, the deep root penetration can draw more available moisture in the soil.
  •  Plant/ Establish early

Areas with light soil (sandy areas), early establishment is advised. Available moisture content stored in the soil will increase the germination rate of sugarcane crop during this dry weather.
Early establishment on sandy area.

  • Irrigate

Conduct inventory of all the available water sources (ground water, SWIP, NIA, open channel) that will be utilized to sustain the moisture requirement of sugarcane growth. Proper placement of the irrigation wells will ensure efficiency and cost reduction.

  •  Use drought/water logged tolerant varieties

Certain varieties can tolerate mild drought and some can stand moisture stress. Knowing the areas vulnerable to weather, variety planning can be implemented properly. Plant the suitable varieties at a specific agroclimatic condition.

  •  Monitor the weather pattern

Install automatic weather stations to observe and record weather patterns. With the aid of weather data, farm operations can be in sync with the weather opportunity to grow and have a higher productivity.


FURTHER STUDY

Improved crop estimation is expected with the use of the vulnerability map. The exact location and size that will be affected with such climate abnormalities will help us understand the productivity drop in these areas. Vulnerability map is a very useful tool in decision making and policy creation that will guide the stake holders. Efficiency of farm inputs and also maximizing the profit is the primary objective of both the miller and the planter. Quantifying accurately is the next step in further analysing the crop yield.. For further analysis the following should be establish.

  •  The crop stage. This is vital in analysing the extent of possible losses in terms of production. At different growth stages of sugarcane yield loss due to weather condition also varies.
  •  Type of variety and crop class. Yield response to different weather condition is dependent on the variety performance and crop class (plant cane or ratoon)



References:
GIS based agriculture,Rajeew Kumar G.B.Pant University of Agriculture & Technology, Pantnagar-Uttrakhand
The use of GPS and mobile mapping for decision-based precision ...
http://www.gisdevelopment.net/application/agriculture/overview/agrio0011pf.htm
Ikisan - Sugarcane Under Moisture stress Conditions
http://www.ikisan.com/Crop%20Specific/Eng/links/ap_sugarcaneWater%20Management.shtml
Porosity of Different Types of Soils | eHow.com
http://www.ehow.com/list_6608020_porosity-different-types-soils.html
Total Porosity web.ead.anl.gov/resrad/datacoll/porosity.htm