Dryland Management Research Articles

Natural climate solutions in Indonesia: wetlands are the key to achieve Indonesia’s national climate commitment

Indonesia offers a dramatic opportunity to contribute to tackling climate change by deploying natural climate solutions (NCS), increasing carbon sequestration and storage through the protection, improved management, and restoration of drylands, peatlands, and mangrove ecosystems. Here, we estimate Indonesia’s NCS mitigation opportunity for the first time using national datasets. We calculated the maximum NCS mitigation potential extent using datasets of annual national land cover, peat soil, and critical lands. We collated a national emissions factor database for each pathway, calculated from a meta-analysis, recent publications from our team, and available literature. The maximum NCS mitigation potential in 2030 is 1.3 ± 0.04 GtCO2e yr−1, based on the historical baseline period from 2009–2019. This maximum NCS potential is double Indonesia’s nationally determined contribution (NDC) target from the forestry and other land use sector. Of this potential opportunity, 77% comes from wetland ecosystems. Peatlands have the largest NCS mitigation potential (960 ± 15.4 MtCO2e yr−1 or 71.5 MgCO2e ha−1 yr−1) among all other ecosystems. Mangroves provide a smaller total potential (41.1 ± 1.4 MtCO2e yr−1) but have a much higher mitigation density (12.2 MgCO2e ha−1 yr−1) compared to dryland ecosystems (2.9 MgCO2e ha−1 yr−1). Therefore, protecting, managing, and restoring Indonesia’s wetlands is key to achieving the country’s emissions reduction target by 2030. The results of this study can be used to inform conservation programs and national climate policy to prioritize wetlands and other land sector initiatives to fulfill Indonesia’s NDC by 2030, while simultaneously providing additional co-benefits and contributing to COVID-19 recovery and economic sustainability.

Prevalence and drivers of abrupt vegetation shifts in global drylands

The constant provision of plant productivity is integral to supporting the liability of ecosystems and human wellbeing in global drylands. Drylands are paradigmatic examples of systems prone to experiencing abrupt changes in their functioning. Indeed, space-for-time substitution approaches suggest that abrupt changes in plant productivity are widespread, but this evidence is less clear using observational time series or experimental data at a large scale. Studying the prevalence and, most importantly, the unknown drivers of abrupt (rather than gradual) dynamical patterns in drylands may help to unveil hotspots of current and future dynamical instabilities in drylands. Using a 20-y global satellite-derived temporal assessment of dryland Normalized Difference Vegetation Index (NDVI), we show that 50% of all dryland ecosystems exhibiting gains or losses of NDVI are characterized by abrupt positive/negative temporal dynamics. We further show that abrupt changes are more common among negative than positive NDVI trends and can be found in global regions suffering recent droughts, particularly around critical aridity thresholds. Positive abrupt dynamics are found most in ecosystems with low seasonal variability or high aridity. Our work unveils the high importance of climate variability on triggering abrupt shifts in vegetation and it provides missing evidence of increasing abruptness in systems intensively managed by humans, with low soil organic carbon contents, or around specific aridity thresholds. These results highlight that abrupt changes in dryland dynamics are very common, especially for productivity losses, pinpoint global hotspots of dryland vulnerability, and identify drivers that could be targeted for effective dryland management.

What is the potential to improve food security by restructuring crops in Northwest China?

Exploring the potential of crop type adjustment to improve regional food security, ecological security and net economic benefits is significant for agricultural water management, green production and sustainable development in drylands. Previous studies on the optimization of crop type were mostly concentrated within the region, without considering the impact of interregional food trade on the adjustment of regional crop type. It is difficult to give full play to the advantages of crop type optimization in improving regional food security. This paper introduces the virtual water trade theory into the optimization model of crop type. By quantifying the water footprint, carbon footprint, crop calories and net economic benefits of food crops in Northwest China and Central Asia. On the basis of fully considering farmers' planting willingness in Northwest China and food trade with Central Asian, the relative and absolute comparative advantage index is used as the optimization coefficient of the model. The food security and ecological security of the region, the blue water use efficiency, the green water ratio and the net food efficiency of the provinces (districts) in the region were used as objective functions to construct an open-ended crop type optimization model to optimize the crop type in the region. The results showed that the use of the constructed open crop type optimization model to guide regional food crop type adjustment increased the calories and grey water footprint provided by regional crops by 7.5% and −6.6%, respectively. The provinces in the region have seen varying degrees of improvement in the benefits of blue water use and net economic benefits, particularly in Gansu Province, which have increased by 51.0% and 53.5%, respectively. Due to the effect of crop type adjustment on the regional green water footprint and carbon footprint targets is less than satisfactory. On this basis, effective suggested measures to improve the efficiency of crop green water use and reduce the carbon footprint were proposed. In this study, the combination of relevant measures and grain crop type adjustment can give full play to the role of grain crop type adjustment in alleviating regional water resources and ecological pressure, improving food security, ecological security and sustainable grain production. It is expected to ensure global food security and promote green production and sustainable development of crops.

C, N, P, K stoichiometric characteristics of the “leaf-root-litter-soil” system in dryland plantations

• Tree species and afforestation years affected nutrient cycling of plantations. • The highest C was in fine roots and the highest N, P and K was in green leaves. • Green leaves absorbed more P and maintained P homeostasis to alleviate P limitation. • Caragana korshinskii was more suitable for ecological restoration in drylands. Plantation’s nutrient cycling can regulate and affect the material cycling of ecosystems, which is the key to maintain the sustainable development of the plantation ecosystem. However, the current understanding of the nutrient cycling characteristics of the “leave-root-litter-soil” continuum of dryland plantation ecosystems is limited. Therefore, in the Longzhong Loess Plateau of China, we selected nine typical dryland plantations to carry related research, including two evergreen ( Platycladus orientalis (13-years and 50-years) and Pinus tabuliformis ) and four deciduous ( Caragana korshinskii (13-years, 35-years and 55-years), Armeniaca sibirica , Populus hopeiensis and Tamarix chinensis ) tree species, and measured C, N, P and K contents of green leaves, fine roots, leaf litter and surface soil (0–20 cm). Results showed tree species and afforestation years strongly changed C, N, P and K contents and ratios of green leaves, fine roots, leaf litter and soil components, and also significantly affected leaf N, P and K reabsorption efficiencies. The average N, P and K contents of four components and soil available nitrogen (AN), available phosphorus (AP) and available potassium (AK) contents in deciduous plantations were higher than those in evergreen plantations, resulting in the lower C:N:P:K stoichiometry of deciduous plantations than evergreen plantations. Especially in 55-years C. korshinskii plantation, its soil C, N, AN, AP and AK contents were higher than those in A. sibirica , P. hopeiensis , P. orientalis and P. tabuliformis plantations. Moreover, soil C, N, P, AN, AP and AK contents in C. korshinskii plantations increased significantly with the increase of afforestation years. Thus, C. korshinskii was more suitable for ecological restoration in drylands. Due to the P limitation in plantations, P reabsorption efficiency was higher than N reabsorption efficiency, and significantly negatively correlated with P contents of four components. And green leaves had the homeostasis to soil AP, which may be the nutrient utilization strategies for plantations to alleviate P limitation. Correlation analysis revealed that the C cycling appeared in green leave-fine root and green leave-leaf litter, the N cycling appeared in green leave-leaf litter-soil-fine root, and the P cycling and K cycling appeared in green leave-leaf litter- soil and leaf litter-fine root. These results will provide guidance for ecological restoration and plantation management in drylands.

Optimising Water Management in Drylands to Increase Crop Productivity and Anticipate Climate Change in Indonesia

In the future, Indonesia will become increasingly dependent on dryland agriculture. New adaptive technology innovations able to transform drylands into arable land throughout almost the entire year have been developed to anticipate global climate change in tropical areas. This article reviews the results of research on the importance of climate and water management technology to increase the crop index and productivity in Indonesia. We found that irrigation treatment at 80% of the FAO-recommended rate resulted in the highest maize stover yield (around 13.65–14.10 t h−1). Irrigation treatment at 60% of the FAO-recommended rate for soybeans (at 0.24 L s−1 h−1) produced good-quality soybean seeds. The use of existing water resources can increase the planted area from 1.25 to 1.67 and increase the cropping index during the second planting season in the same area. Agricultural systems based on water management can improve their crop index and productivity, and anticipate climate change to increase farmers’ incomes and wellbeing. Support measures in the form of regulations, legislation, acts, programmes, and policies from central and local governments for land use and management are crucial. The development of infrastructure by establishing water management institutions at the village/farmers’ group levels to allocate irrigation water is a leverage point to develop dryland agricultural systems appropriately and judiciously to assist in sustainable development.

Sustainability Analysis on Economic and Ecological Aspects of Dry Land Management in Jerowaru District Using Multi Dimensional Scaling (MDS)

This study aims to determine the factors from the ecological and economic aspects that have the most sensitive attributes in influencing the sustainability of dry land management in Jerowaru District. This study uses the Multi Dimensional Scaling (MDS) analysis of Rapfish. The population in this study were all dry land farmers in Jerowaru District, East Lombok. The number of farmer respondents surveyed was 90 farmers spread over three villages with varied agricultural cropping patterns and topography. The sample unit in this study were individuals, namely dry land farmers. The sample in this research is some farmers who do dry land management. The analysis used is descriptive and MDS Rapfish is supported by qualitative analysis from field observations and in-depth interviews as outlined in a descriptive analysis to determine the characteristics of each respondent while MDS Rapfish is used to determine the most sensitive factors on ecological and economic aspects. The results of the feasibility study were tested with the r2 value which is close to one and the stress value <20% and the results of the Monte Carlo analysis which have a difference of <5% with the MDS results. The results of the MDS analysis show that the sustainability status on the economic aspect is 46.3 and on the ecological aspect it is 39.08. On the economic and ecological aspects in the less sustainable category. Leveraging factors from leveraging analysis to improve the status of sustainability in the economic aspect are the availability of inputs, especially fertilizers, access to marketing and availability of water for farming. While the lever factors in the ecological aspect are the use of biochar, the occurrence of floods / landslides, and vegetation cover. These levers must be a priority for sustainable dryland agricultural management in Jerowaru District, East Lombok.

Fallow replacement cover crops impact soil water and nitrogen dynamics in a semi-arid sub-tropical environment

Conventional dryland cropping systems rely upon frequent and lengthy fallow periods to conserve soil water and mineral nitrogen to stabilize crop production. However, this is associated with depletion of soil organic matter and decreased fallow efficiency. Intensifying cropping systems by planting cover crops has been touted as a means to stem soil organic matter loss and improve fallow efficiency. We investigated whether the manipulation of cover crop functional trait diversity and sowing proportions (utilizing Poaceae, Fabaceae, and Brassicaceae) could provide complementary functions that improve soil water and mineral N management during fallow. Grass-legume mixtures represented the best compromise between biomass production (> 4000 kg DM ha˗1), N retention (142 kg N ha˗1), N supply via biological N fixation (35 kg N ha˗1) and maintained an additional 70 mm of water at the end of fallow period. Regardless of functional trait type, cover crops increased N retention but maintained similar soil mineral N content at the end of fallow period. However, soil water effects were functional trait-specific, and there were significant soil water deficits with brassica-dominated cover crops. Soil water accumulation post cover crop termination was significantly higher in cover crops compared with conventional fallows, but the overall fallow efficiency was higher in the conventional fallow. This study demonstrates that cover crops are not universally beneficial, and careful selection of cover crop functional traits in mixtures could enhance fallow soil water and N management in semi-arid sub-tropical drylands.

Interacting water, nutrients, and shrub age control steppe grass‐on‐shrub competition: Implications for restoration

AbstractUnderstanding the factors that control grass–shrub interactions and coexistence is critical to the design of dryland management and restoration strategies. Using Stipa tenacissima tussocks as adult neighbor and Olea europaea var. sylvestris as target woody species, we performed a 5‐year‐long, large‐scale manipulative experiment to investigate the independent and combined effects of water and nutrient availability, and the modulating effects of O. europaea ontogeny on the net outcome of grass–shrub interaction. At two contrasting dryland sites, we conducted experimental plantings of Olea seedlings on two microsites: contiguous to a Stipa tussock (Stipa microsite) and on the intertussock bare‐soil areas (Open microsite), and manipulated resource availability by combining nutrient and water addition. The experiment followed a full factorial design, with all treatment combinations applied at each site. We monitored survival, height, and stem basal diameter of Olea individuals over a study period of 5 years. All across the wide range of conditions considered, negative effects of Stipa on Olea largely prevailed during the first 2 years after the plantation. We found that competition was stronger in the drier steppe, where extra inputs of water favored neutral interactions. Conversely, nutrient addition increased competition strength, particularly when combined with water inputs, pointing to the contrasting role of different resources and the importance of interactions between them in the control of plant–plant interaction outcome. The competition effects of Stipa faded with time and gradually shifted to neutral interaction as Olea individuals aged. Our results are particularly relevant to guide restoration efforts in formerly wooded xeric grasslands and rangelands.

Soil health within transitions from irrigation to limited irrigation and dryland management

AbstractThe decline in groundwater supply in the Texas High Plains is forcing some growers to convert center‐pivot irrigated cropland to dryland production. Transitioning toward reduced water input can lead to declines in soil health. We assessed short‐term changes in soil health indicators in two transition scenarios: (a) from high irrigation method to low irrigation method (center pivot to subsurface drip) and (b) from high irrigation method to dryland (center pivot to dryland), in comparison to continuous center‐pivot management. We monitored changes in chemical and biological indicators in four fields for each transition scenario and in three pivot‐irrigated fields. There were declines in soil water content, potassium (K), sodium (Na), and soil organic carbon with transition from irrigation to reduced irrigation and dryland. Severe drought in the final year revealed reduced amounts of multi‐enzyme activities, total ester‐linked fatty acid methyl ester (EL‐FAME), and total fungi. Transitioning to low water‐input management in this environment complicates efforts to maintain microbial components of soil health. Longer‐term comparisons are needed to detect slow changes in soil health indicators on producers’ fields.

Characterization of soil nematode community structure in semi‐arid dryland barley systems

AbstractSoil nematode community structure and composition can inform crop managers about soil quality. However, few studies have assessed the nematode community under agricultural systems in cool semi‐arid regions such as the U.S. northern Great Plains. We assessed soil nematode community structure of barley (Hordeum vulgare L.) and barley–pea (Pisum sativum L.) cropping systems from 2016 to 2018 in one tilled and two no‐till field experiments under dryland management in central and southwestern Montana. Soils were sampled prior to planting in the spring and following harvest in late summer and nematodes were classified to genus level via microscopy. Both in season moisture stress and overwinter stress explained decline in nematodes in the central Montana no‐till experiments, although consistent impacts of moisture or overwinter stress on nematodes were not detected in the tilled field experiment. Cropping system or sequence did not impact the nematode population (p > .1), but barley yield was positively correlated with larger nematode populations in both no‐till experiments (r > .60). The percentage of fungivores were negatively correlated (r = –.42) to barley yield under tillage. Plant parasitic nematodes were positively correlated (r = .43) to barley yield under tillage. These results suggest that factors which enhance cereal crop growth and productivity rather than crop diversification drive short‐term nematode community dynamics when crop rotations are established in cool semi‐arid regions. Future work is needed to determine if cropping system changes can impact nematode populations after several years in cool semi‐arid regions and, if so, what ecosystem services result from these transformations.

Wastewater‐recycled struvite as a phosphorus source in a wheat–soybean double‐crop production system in eastern Arkansas

AbstractFertilizer‐phosphorus (P) sources are mainly derived from rock phosphate (RP), which is a finite, actively mined resource. With growing human populations globally, alternative P sources are vitally important to ensure future food security. Precipitation of the mineral struvite (MgNH4PO4·6H2O) from wastewater could be a potential alternative fertilizer‐P option from crop production. The objective of this study was to evaluate the effects of chemically precipitated struvite (CPST), compared with triple superphosphate (TSP) and an unamended control (UC) treatment, and irrigation (irrigated and non‐irrigated/dryland) on above‐ (dry matter, yield, and tissue‐N, ‐P, and ‐Mg concentrations and uptake) and belowground (root tissue N, P, and Mg concentrations) soybean [Glycine max (L.) Merr.] and wheat (Triticum aestivum L.) response in a wheat–soybean, double‐crop production system on a silt‐loam soil (Aquic Fraglossudalfs) in eastern Arkansas. Soybean aboveground and wheat belowground Mg concentrations were 1.1 and 1.2 times, respectively, greater (p < .05) from CPST than from TSP, while soybean belowground Mg and wheat stem P concentrations were similar between CPST and TSP. Wheat stem Mg and belowground N concentrations were 1.1 times greater (p < .05) from TSP than from CPST. Soybean seed P and Mg concentrations were 1.2 and 1.1 times, respectively, greater (p < .05) under irrigated than under dryland management. Results substantiate the use of CPST as a potential alternative fertilizer‐P and ‐Mg source on a silt‐loam soil for crop production. Using wastewater‐recovered nutrients in a production‐scale setting may offset the need for energy‐intensive commercial fertilizers to supply essential plant nutrients.

English

The research objective was to formulate a sustainable dryland management strategy in Buleleng Regency, Bali Province. The results showed that the effective strategies were namely: (1) Utilizing available dryland to increase the quantity and quality of agricultural production; (2) Utilizing the research results of research institutes of the Ministry and University related to dryland; (3) Attracting investors to invest in the use of dryland, strengths-threats (ST) strategies; (4) Rearranging of inheritance of agricultural land to avoid narrowing agricultural land owners; (5) Application of agricultural technology 4.0 to attract millennials to work in agriculture; the weakness-opportunity (WO) strategy, (6) Increasing the productivity of dryland by applying technology produced by ministerial research institutes and University, (7) Increasing the availability of facilities and infrastructure to support dryland development, such as making jubang, drip irrigation, etc. (8) Increasing capital and facilitating access to capital, and market networks and partnership systems; The WT strategy, (9) Implementing the Perpetual Land Law to prevent land conversion for non-agricultural purposes, and (10) Improving the quality of farmers' human resources through trainings, so that farmers have the ability to take advantage of existing technology. Key words: Sustainable, dryland, strategy, management, strengths-opportunity (SO), strengths, weaknesses, opportunities, threats (SWOT).  

English

The East African drylands cover about 47% of the land surface and host about 20 million people. Rural people living in the drylands are mainly pastoralists who depend on livestock for both economic and social well-being. During the dry season, pastoralists apply strategic mobility to access grazing resources efficiently. However, this strategy has experienced change and constraints due to various demographic- and climate-related challenges. Pastoral lands have been cleared for large-scale agriculture while pastoralists have shifted towards agro-pastoralism. This has eroded many dryland trees and forests leading to environmental degradation. This review discusses important indigenous trees that can be utilized in ecological restoration of drylands as well as providing ecosystem goods and services. These include trees for gums and resins (Acacia, Commiphora and Boswellia), indigenous fruit trees (IFTs) (Adansonia digitata, Tamarindus indica and Balanites aegyptiaca), trees for wood (Melia volkensii and Terminalia brownie) and fodder (Acacia tortilis and Faidherbia albida). They are not only drought-tolerant but also have minimal disruption to the ecosystem. Various dryland restoration strategies and constraints are also discussed. For successful establishment, seedling planting should be integrated with other appropriate practices such as natural regeneration, silviculture and enrichment planting for sustainable dryland management.  Key words: Ecological restoration, drylands, indigenous trees, pastoralism.

Uncertainty analysis in parameter regionalization for streamflow prediction in ungauged semi-arid catchments

ABSTRACT Predicting in ungauged basins (PUB) depends on the modelling uncertainties in the donor catchments (DCs). However, PUB is normally limited to a unique outcome, which may be quite uncertain, mainly in semi-arid basins where streamflow variability is high. Our goal is to assess the uncertainty in the parameter regionalization for streamflow prediction in semi-arid ungauged basins (UB). We used Differential Evolution Adaptive Metropolis (DREAM) for a parameter calibration that considers its intrinsic uncertainty. A basin similarity regionalization was performed to transfer the parameters to UB, considering one, three and five DCs. Leave-one-out cross-validation was applied for 28 gauged catchments. Regionalization performance had average Nash-Sutcliffe efficiency above 0.50. The approach considering one DC performed better than the others. The model of a poorly monitored catchment performed better using the transferred parameters from long-recorded, similar catchments than using those calibrated in the catchment itself. The developed regionalization may be a relevant tool for water management in drylands.

Assessment of Vegetation Dynamics and Ecosystem Resilience in the Context of Climate Change and Drought in the Horn of Africa

Understanding the response of vegetation and ecosystem resilience to climate variability and drought conditions is essential for ecosystem planning and management. In this study, we assessed the vegetation changes and ecosystem resilience in the Horn of Africa (HOA) since 2000 and detected their drivers based mainly on analysis of the Moderate Resolution Imaging Spectroradiometer (MODIS) products. We found that the annual and seasonal trends of NDVI (Normalized Difference Vegetation Index) generally increased during the last two decades over the Horn of Africa particularly in western parts of Ethiopia and Kenya. The weakest annual and seasonal NDVI trends were observed over the grassland cover and tropical arid agroecological zones. The NDVI variation negatively correlated with Land Surface Temperature (LST) and positively correlated with precipitation at a significant level (p < 0.05) account for 683,197 km2 and 533,385 km2 area, respectively. The ecosystem Water Use Efficiency (eWUE) showed overall increasing trends with larger values for the grassland biome. The precipitation had the most significant effect on eWUE variation compared to LST and annual SPEI (Standardized Evapotranspiration Index). There were about 54.9% of HOA resilient to drought disturbance, whereas 32.6% was completely not-resilient. The ecosystems in the humid agroecological zones, the cropland, and wetland were slightly not-resilient to severe drought conditions in the region. This study provides useful information for policy makers regarding ecosystem and dryland management in the context of climate change at both national and regional levels.

The Resilient Recurrent Behavior of Mediterranean Semi-Arid Complex Adaptive Landscapes

Growing external pressures from human activities and climate change can exacerbate desertification, compromising the livelihoods of more than 25% of the world’s population. The dryland mosaic is defined by land covers that do not behave similarly, and the identification of their recurring or irregular changes over time is crucial, especially in areas susceptible to become desertified. To this aim, the methodological approach of this research is based on the integration of non-linear data analysis techniques, such as recurrence plots (RPs) and recurrence quantification analysis (RQA), applied to the Enhanced Vegetation Index (EVI), which is a functional ecological proxy of above ground net primary production. The research exploits the recurring change detected in vegetation cover over time to gauge the predictable (resilient) behavior of the EVI as well as its chaoticity in a semi-arid Mediterranean region (Apulia, Italy). Interestingly, the results have shown the spatial rendering of recurrence variables, confirming the well-known hot spots of soil degradation and desertification taking place in the region, which are characterized by greater EVI chaoticity, but they have also identified new potential candidate sites. As a result, the susceptibility to land degradation, as measured by the EVI-RQA approach, can help in measuring land desertification with evident operational benefits for landscape planning. The novelty of the research lies in the spatially explicit identification of resilient and less resilient areas to desertification that can support the definition of more targeted interventions and conservation priorities for better planning and sustainable management of Mediterranean drylands.

Soil quality indices as affected by long‐term burning, irrigation, tillage, and fertility management

AbstractUnderstanding the impacts of long‐term agricultural practices on soil quality (SQ) is key for sustaining agroecosystem productivity. This study investigated conventional and no‐tillage (NT), residue burning and no burning, residue level (high and low), and irrigation (irrigated and dryland) effects on soil properties, SQ, and crop yields following 16 yr of a wheat (Triticum aestivum L.)–soybean [Glycine max (L.) Merr.] double‐crop system via the Soil Management Assessment Framework (SMAF). A field experiment was conducted in the Lower Mississippi River Delta region on a silt‐loam soil. Bulk density, soil organic C (SOC), total N (TN), pH, electrical conductivity (EC), and soil P and K from the 0‐ to 10‐cm soil depth were used as SQ indicators investigated individually and as an overall soil quality index (SQI). Following 16 yr, residue burning reduced SOC (1.1%) compared with no burning (1.24%). Irrigation resulted in greater soil TN than dryland management systems (p < 0.05). Reduced soil pH and extractable soil P and K occurred under NT, high residue, and irrigated treatments. Irrigation increased soybean yields, regardless of the tillage system. Burned, NT–high residue management increased wheat yields (3.45 Mg ha−1). Irrigation reduced SQ because of low EC and K scores. High residue reduced SQ compared with the low residue treatment within NT systems, owing to low pH scores. The SMAF indices identified the impacts of irrigation, NT, and optimal N fertilization on SQ. Monitoring of soil pH, P, and K may be needed to maintain SQ in long‐term wheat–soybean systems.

PEMANFAATAN DAN OPTIMALISASI LAHAN KERING UNTUK PENGEMBANGAN BUDIDAYA TANAMAN PALAWIJA DI DESA PUDAY KECAMATAN WONGEDUKU KABUPATEN KONAWE PROVINSI SULAWESI TENGGARA

Land is one of the potential natural resources to be developed optimally to increase local revenue. Based on the availability of water, land is grouped into two major groups, which are wetland and dry land (upland). The use of dry land for agriculture is often ignored by policy makers. Problems in dry land management vary in each region, both technical and socio-economic aspects. However, with the right strategy and technology, these problems can be overcome. Efforts to manage dry land to increase food production face problems, including steep slopes, low soil fertility, and water shortages. These problems need to be overcome by applying the right technology. Dry land management technology is available, including management of soil fertility, soil conservation, land rehabilitation, and efficient management of water resources. The problem is the weak dissemination of innovative technology to farmers and the slow adoption of this technology. Utilization of dry land to increase food production requires appropriate planning and strategies.

Ecosystem Services of Indigenous Kaliwu Agroforestry System in Sumba, Indonesia

Agroforestry is an environmentally friendly land resource management applied by farmers in various countries. The differences in ethnicity, geography, biophysical environment, and socio-economic background influence the application of this agricultural model, known as indigenous agroforestry. However, information on the management and ecosystem services of indigenous agroforestry in semi-arid ecosystems is not widely known. This research examined the management and provision of service for the Indigenous Kaliwu Agroforestry System (IKAS) on Sumba island. It was carried out in the Central Sumba regency using survey and observation methods in 70 sample units of farmer households distributed in 7 villages. Data were collected through interviews and observations on IKAS management initiatives, including provision services for foodstuff, fuelwood, timbers, and fodders. The results showed that IKAS is a local initiative model for the management of flora biodiversity through the replication of natural forest models in traditional cultivation environments. This is reflected by the plant’s biodiversity developed at IKAS, including endemic and cultural keystone species. The development of various plant species has implications for the provision services for foodstuff in form of tubers and fruits, fuelwood, timbers, and fodder. In addition, IKAS plays a role in supporting sustainable dryland management, biodiversity conservation, and farmers’ livelihoods. This research recommends that the optimization of the IKAS role for community livelihoods and environmental conservation be carried out through the support of its development policies by local government in Sumba.

Soil Quality Assessment in Relation to Food Crop Productivity to Support Agribusiness-Based of Dry Land Management by Scoring of Soil Quality

To support Indonesian’s food self-sufficiency program, more quantitative and accurate data are required on the character of soil data needed, which can be more easily understood, practical and suitable for crop selection as well as for the right fertilizer recommendations to support the agribusiness development, implementation and operation. The purpose of this research is to develop and assess soil quality in relation to the productivity of major food crops by using Soil Quality Score Plus (SQS Plus) to support agribusiness-based management of dry lands. The use of SQS for assessing soil quality in principle determines the weighted average score obtained from the score of each selected key parameter multiplied by its weight. The SQS for the 36 locations observed varies from 2.36 (low) to 4.12 (high). SQS Plus adds letter(s) after a score to indicate the limiting factor(s) of soil ecosystem. The most limiting factor is low carbon organic content (72.2 % from the 36 locations observed), followed by low P availability (58.3%), and low total organic N (41.7%). Data of correlation between SQS and crop productivity is not good as expected. Crop growth and crop production are not only determined by soil quality and its limiting factors.
 
 Keywords: Crop productivity, dry land management, soil limiting factors, soil quality assessment, Soil Quality Score