Economic performance and sustainability of a novel intercropping system on the north China plain
Huang, C. ; Liu, Q. ; Heerink, N.B.M. ; Stomph, T.J. ; Li, B. ; Liu, R. ; Zhang, H. ; Wang, C. ; Li, X. ; Zhang, C. ; Werf, W. van der; Zhang, F. - \ 2015
PLoS ONE 10 (2015)8. - ISSN 1932-6203 - 16 p.
reducing environmental risk - nutrient-use efficiency - food security - crop productivity - n management - resource use - agriculture - competition - fertilizer - diversity
Double cropping of wheat and maize is common on the North China Plain, but it provides limited income to rural households due to the small farm sizes in the region. Local farmers in Quzhou County have therefore innovated their production system by integration of watermelon as a companion cash crop into the system. We examine the economic performance and sustainability of this novel intercropping system using crop yield data from 2010 to 2012 and farm household survey data collected in 2012. Our results show that the gross margin of the intercropping system exceeded that of the double cropping system by more than 50% in 2012. Labor use in the intercropping system was more than three times that in double cropping. The lower returns per labor hour in intercropping, however, exceeded the average off-farm wage in the region by a significant margin. Nutrient surpluses and irrigation water use are significant larger under the intercropping system. We conclude that the novel wheat-maize/watermelon intercropping system contributes to rural poverty alleviation and household-level food security, by raising farm incomes and generating more employment, but needs further improvement to enhance its sustainability.
Fish abundance, fisheries, fish trade and consumption in sixteenth-century Netherlands as described by Adriaen Coenen
Bennema, F.P. ; Rijnsdorp, A.D. - \ 2015
Fisheries Research 161 (2015). - ISSN 0165-7836 - p. 384 - 399.
pleuronectes-platessa l - atlantic bluefin tuna - southern north-sea - cod gadus-morhua - wadden sea - population-dynamics - medieval europe - resource use - lower rhine - history
Concern about fisheries impact on marine ecosystems has raised the interest in the reconstruction of the state of marine ecosystems and the nature of the human activities in the past. We present late 16th century information on the occurrence and relative abundance of biota in Dutch coastal and inland waters (50 marine fish, 13 diadromous or freshwater and 4 marine mammal species), as well as a description of the sea fisheries (target species, fishing grounds, gear), fish trade, export, and fish consumption in Holland as documented in the handwritten Fish Book by Adriaen Coenen (1577–1581). The species composition and abundances are compared to published trawl survey data from around 1900 and in the 1990s. Fish species that have disappeared almost completely, were already rare around 1900 and are characterised by a large body size (rays and sharks, sturgeon, ling), whereas currently abundant species were already abundant in the 16th century. Intensive fisheries for herring occurred near Orkney, Fairhill and Shetland. Coastal and freshwater fisheries provided fresh fish for local as well as export markets, but also provided bait for the massive offshore hook and line fishery for the production of salted cod, which remained largely unnoticed. Dried flatfish were exported to Germany. Consumption of fish and marine invertebrates differed between social classes. Coenen distinguished eight consumer categories, a refinement of the categories ‘rich’ and ‘poor’ used in archaeological studies.
Enhanced Input of Terrestrial Particulate Organic Matter Reduces the Resilience of the Clear-Water State of Shallow Lakes: A Model Study
Lischke, B. ; Hilt, S. ; Janse, J.H. ; Kuiper, J.J. ; Mehner, T. ; Mooij, W.M. ; Gaedke, U. - \ 2014
Ecosystems 17 (2014)4. - ISSN 1432-9840 - p. 616 - 626.
climate-change - food webs - humic substances - resource use - fresh-water - loch ness - land-use - carbon - ecosystem - phosphorus
The amount of terrestrial particulate organic matter (t-POM) entering lakes is predicted to increase as a result of climate change. This may especially alter the structure and functioning of ecosystems in small, shallow lakes which can rapidly shift from a clear-water, macrophyte-dominated into a turbid, phytoplankton-dominated state. We used the integrative ecosystem model PCLake to predict how rising t-POM inputs affect the resilience of the clear-water state. PCLake links a pelagic and benthic food chain with abiotic components by a number of direct and indirect effects. We focused on three pathways (zoobenthos, zooplankton, light availability) by which elevated t-POM inputs (with and without additional nutrients) may modify the critical nutrient loading thresholds at which a clear-water lake becomes turbid and vice versa. Our model results show that (1) increased zoobenthos biomass due to the enhanced food availability results in more benthivorous fish which reduce light availability due to bioturbation, (2) zooplankton biomass does not change, but suspended t-POM reduces the consumption of autochthonous particulate organic matter which increases the turbidity, and (3) the suspended t-POM reduces the light availability for submerged macrophytes. Therefore, light availability is the key process that is indirectly or directly changed by t-POM input. This strikingly resembles the deteriorating effect of terrestrial dissolved organic matter on the light climate of lakes. In all scenarios, the resilience of the clear-water state is reduced thus making the turbid state more likely at a given nutrient loading. Therefore, our study suggests that rising t-POM input can add to the effects of climate warming making reductions in nutrient loadings even more urgent.
Challenges for crop production research in improving land use, productivity and sustainability
Spiertz, J.H.J. - \ 2013
Sustainability 5 (2013)4. - ISSN 2071-1050 - p. 1632 - 1644.
food security - resource use - bioenergy production - trade-offs - energy - yield - agriculture - adaptation - management - services
The demand for food, feed, and feedstocks for bioenergy and biofactory plants will increase proportionally due to population growth, prosperity, and bioeconomic growth. Securing food supply and meeting demand for biomass will involve many biological and agro-ecological aspects such as genetic plant improvement, sustainable land use, water-saving irrigation, and integrated nutrient management as well as control of pests, diseases and weeds. It will be necessary to raise biomass production and economic yield per unit of land—not only under optimum growing conditions, but even more under conditions constrained by climate, water availability, and soil quality. Most of the advanced agronomic research by national and international research institutes is dedicated to the major food crops: maize, rice, wheat, and potato. However, research on crops grown as feedstock, for bio-energy and industrial use under conditions with biophysical constraints, is lagging behind. Global and regional assessments of the potential for growing crops are mostly based on model and explorative studies under optimum conditions, or with either water or nitrogen deficiencies. More investments in combined experimental and modeling research are needed to develop and evaluate new crops and cropping systems under a wide range of agro-ecological conditions. An integral assessment of the biophysical production capacity and the impact on resource use, biodiversity and socio-economic factors should be carried out before launching large-scale crop production systems in marginal environments.
Contagious cooperation, temptation and ecosystem collapse
Richter, A.P. ; Soest, D. van; Grasman, J. - \ 2013
Journal of Environmental Economics and Management 66 (2013)1. - ISSN 0095-0696 - p. 141 - 158.
resource use - punishment - management - dynamics - evolution - economics - model - extinction - fisheries - systems
Real world observations suggest that social norms of cooperation can be effective in overcoming social dilemmas such as the joint management of a common pool resource—but also that they can be subject to slow erosion and sudden collapse. We show that these patterns of erosion and collapse emerge endogenously in a model of a closed community harvesting a renewable natural resource in which individual agents face the temptation to overexploit the resource, while a cooperative harvesting norm spreads through the community via interpersonal relations. We analyze under what circumstances small changes in key parameters (including the size of the community, and the rate of technological progress) trigger catastrophic transitions from relatively high levels of cooperation to widespread norm violation—causing the social–ecological system to collapse.
Heterogeneity in farmers’ production decisions and its impact on soil nutrient use: Results and implications from northern Nigeria
Berkhout, E.D. ; Schipper, R.A. ; Keulen, H. van; Coulibaly, O. - \ 2011
Agricultural Systems 104 (2011)1. - ISSN 0308-521X - p. 63 - 74.
sustainable agricultural intensification - south-western niger - resource use - systems - management - policy - model - scenarios - dynamics - balances
Sustainable use (in terms of nutrients) of soil resources by farmers in Sub-Saharan Africa is constrained by institutions and markets. This paper explores the case of northern Nigeria, by using a combination of multi-attribute utility theory and bio-economic modelling. This approach allowed us to identify heterogeneity in production strategies and to quantify its effect on the use of soil nutrient resources. We find that farmers with larger land holdings place more emphasis on gross margins in their utility function, while those with larger holdings of fertile fadama fields place more emphasis on sustainability. Risk aversion, operationalised through variance minimization, appears an important attribute in the utility function of many farm households that are more dependent on agriculture for their overall income. A regression analysis shows that differences in production strategies significantly affect nutrient balances, but also shows that such effects are heterogeneous across locations. We find more favourable nutrient balances for some of the more market-oriented farm households who place more emphasis on sustainability. In farm plans of the most risk-averse households, the production of cereals for subsistence consumption dominates and leads to negative soil nutrient balances, especially for potassium. Farmers who place a large importance on gross margins are likely to benefit most from policies aimed at enhancing profitability through improving functioning of markets. The large group of risk-averse farmers will have the largest immediate gain in utility from policies and technologies aimed at reducing production risk in high-value crops. Additional policies aimed at creating a stronger market-oriented production by the least-endowed farm households could play a role in reducing intensity of soil fertility mining. Under these conditions, the efficient cropping pattern shifts partially from cereal cropping to high-value crops, associated with higher input use. The main results are similar to those in other studies, although some of the nutrient balances are less negative. The results do appear to be sensitive to the type of cropping activities included in the analysis, and additional methodological research is required. Extensions of the used method should further account for temporal and spatial differences in soil fertility, leading to differences in nutrient uptake and production, as well as potential temporal heterogeneity in production strategies.
Nitrogen, sustainable agriculture and food security. A review
Spiertz, J.H.J. - \ 2010
Agronomy for Sustainable Development 30 (2010)1. - ISSN 1774-0746 - p. 43 - 55.
dry-matter production - different water-regimes - wheat cropping systems - dairy farming systems - nutrient management - organic agriculture - resource use - ecosystem services - use efficiency - field margins
The impact of modern agriculture on natural resources has become a major global concern. Population growth and expanding demand for agricultural products constantly increase the pressure on land and water resources. A major point of concern for many intensively managed agricultural systems with high external inputs is the low resource-use efficiency, especially for nitrogen. A high input combined with a low efficiency ultimately results in environmental problems such as soil degradation, eutrophication, pollution of groundwater, and emission of ammonia and greenhouse gases. Evidently, there is a need for a transition of current agricultural systems into highly resource-use efficient systems that are profitable, but at the same time ecologically safe and socially acceptable. Here, opportunities to improve nitrogen-use efficiency in cropping and farming systems are analyzed and discussed. In the past and present, increased productivity of the major plant production systems has been derived from genetic improvement, and from greater use of external inputs such as energy, fertilizers, pesticides and irrigation water. Aiming at improving resource-use efficiencies, in high-input systems the focus should be on more yield with less fertilizer N. In low-input systems additional use of N fertilizer may be required to increase yield level and yield stability. Developing production systems that meet the goals of sustainable agriculture requires research on different scales, from single crops to diverse cropping and farming systems. It is concluded that N supply should match N demand in time and space, not only for single crops but for a crop rotation as an integrated system, in order to achieve a higher agronomic N-use efficiency. A combination of quantitative systems research, development of best practices and legislation will be needed to develop more environmentally-friendly agricultural systems. The growing complexity of managing N in sustainable agricultural systems calls for problem-oriented, interdisciplinary research
Light interception and utilization in relay intercrops of wheat and cotton
Zhang, L. ; Werf, W. van der; Bastiaans, L. ; Zhang, S. ; Li, B. ; Spiertz, J.H.J. - \ 2008
Field Crops Research 107 (2008)1. - ISSN 0378-4290 - p. 29 - 42.
radiation-use efficiency - solar-radiation - simple-model - resource use - row crops - growth - systems - productivity - temperature - environment
In China, a large acreage of cultivated land is devoted to relay intercropping of winter wheat and cotton. Wheat is sown in strips with interspersed bare soil in October and harvested in June of the next year, while cotton is sown in the interspersed paths in the wheat crop in April and harvested before the next wheat sowing in October. This paper addresses the question how strip width and number of plant rows per strip of wheat or cotton affect light interception (LI) and light use efficiency (LUE) of both component crops. Field experiments were carried out in three consecutive years: 2002, 2003 and 2004. Light interception and productivity were estimated in monocultures of wheat and cotton and four intercropping designs differing in strip and path width as well as number of rows per strip. The intercrop systems were identified by the number of rows per strip of wheat and cotton, respectively, as 3:1, 3:2, 4:2 and 6:2. Total light interception over a season was calculated from LAI measurements, using a model for light interception in a row crop. The spatial distribution and diurnal course of light in intercrops were also measured with sensors. Wheat monocrops intercepted 618 MJ m¿2 photosynthetically active radiation (PAR) from 18 March to harvest in 2002, 337 MJ m¿2 from 29 April to harvest in 2003, and 457 MJ m¿2 from 13 April to harvest in 2004. Averaged over 3 years, wheat in the four intercrops (3:1, 3:2, 4:2 and 6:2, respectively) intercepted 83, 71, 73 and 75% as much PAR as the sole wheat. From sowing to harvest, cotton monocrops intercepted 491 MJ m¿2 PAR in 2002, 426 MJ m¿2 in 2003, and 415 MJ m¿2 in 2004. Cotton in the four intercrops (3:1, 3:2, 4:2 and 6:2, respectively) intercepted 73, 93, 86 and 67% as much PAR as the sole cotton. LUE of wheat was 2.12 ± 0.14 g total dry matter MJ¿1 PAR during the reproductive period, while that of cotton was 1.33 ± 0.02 g dry matter MJ¿1 PAR over the whole growing period. No differences in LUE of wheat or cotton were found between systems. The analysis indicates that the high productivity of intercrops, compared to monocultures, can be fully explained by an increase in accumulated light interception per unit cultivated area. The component crops are thus complementary in their interception of light over space and time. The model results indicate that light interception can be modified by choice of the number of crop rows per strip and strip width. The best distribution of light is attained in systems with narrow strips, a high proportion of border rows, and high planting densities of cotton. Suggestions for system improvement are given.
Nitrogen economy in relay intercropping systems of wheat and cotton
Zhang, L.Z. ; Spiertz, J.H.J. ; Zhang, S. ; Li, B. ; Werf, W. van der - \ 2008
Plant and Soil 303 (2008)1-2. - ISSN 0032-079X - p. 55 - 68.
nutrient-uptake - reproductive-organs - use efficiency - resource use - growth - crops - responses - china - competition - tillage
Relay intercropping of wheat and cotton is practiced on a large scale in China. Winter wheat is thereby grown as a food crop from November to June and cotton as a cash crop from April to October. The crops overlap in time, growing as an intercrop, from April till June. High levels of nitrogen are applied. In this study, we analyzed the N-economy of the monocultures of cotton and wheat, and of four relay intercropping systems, differing in number of rows per strip of cotton or wheat. Field experiments were carried out from 2001/02 to 2003/04 in the Yellow River region in China. We quantified the nitrogen uptake and nitrogen use efficiency of wheat and cotton in relay intercropping systems to test if intercrops are more resource use efficient in comparison to monocrops. Nitrogen (N) yields of wheat per unit area in the four intercropping systems were lower than in the monocrop, which ranged from 203 to 288 kg ha(-1). The total N-uptake per unit biomass was similar between wheat in mono- and intercrops. On average, the N-yield of cotton per unit area was lower in intercrops than in monocrops, which ranged from 110 to 127 kg ha(-1), but the total N-uptake per unit biomass was higher in intercropped cotton, as dry matter production was reduced to a greater extent by intercropping than N-uptake. The N-uptake of cotton was diminished during the intercropping phase, but recovered partially during later growth stages. The physiological nitrogen use efficiency (IE) of wheat was not much affected by intercropping, but it was reduced in cotton, due to delayed flowering and less reproductive growth. Total N-efficiency of the system was assessed by comparing the relative nitrogen yield total (RNT), i.e. the sum of the ratio's of total N-uptake by a component crop in the intercrop relative to the N-uptake in the monocrop, to the relative yield total. RNT ranged from 1.4 to 1.7, while the relative yield total (RYT) ranged from 1.3 to 1.4, indicating that intercrops used more nitrogen per unit production than monocrops. An analysis of the crop nitrogen balance showed that the nitrogen surplus of sole crops amounted to 220 kg ha(-1) for wheat and 140 kg ha(-1) for cotton, while in the intercropping systems, the annual N surplus exceeded 400 kg ha(-1). Conventional N-management in intercrops thus results in high N-surpluses that pose an environmental risk. The N management could be improved by means of a demand-based rate and timing of N applications.
Assessing the intensity of temperate European agriculture at the landscape scale
Herzog, F. ; Steiner, B. ; Bailey, D. ; Baudry, J. ; Billeter, R. ; Bukacek, R. ; Blust, G. de; Cock, R. de; Dirksen, J. ; Dormann, C. ; DeFilippi, R. ; Frossard, E. ; Liira, J. ; Schmidt, T. ; Stockli, R. ; Thenail, C. ; Wingerden, W.K.R.E. van; Bugter, R.J.F. - \ 2006
European Journal of Agronomy 24 (2006)2. - ISSN 1161-0301 - p. 165 - 181.
land-use intensity - population-dynamics - southern england - natural enemies - farming systems - soil fertility - use efficiency - resource use - intensification - diversity
The intensity of agricultural production was assessed in 25 landscape test sites across temperate Europe using a standardised farmer questionnaire. The intensity indicators, nitrogen input (to arable crops and to permanent grassland), density of livestock units and number of pesticide applications (herbicides, insecticides, fungicides and retardants), were recorded and integrated into an overall intensity index. All three components were needed to appropriately characterise the intensity of agricultural management. Four hypotheses were tested. (i) A low diversity of crops is related to higher intensity. The contrary was observed, namely because diverse crop rotations contained a higher share of crops which are more demanding in terms of nitrogen and of plant protection. (ii) Intensity decreases when there is more permanent grassland. This was confirmed by our study. (iii) Large farms are managed more intensively. There was no relation between farm size and intensity. (iv) Large fields are managed more intensively. There was a tendency towards higher nitrogen input and livestock density in landscapes with larger fields but only a few of the results were statistically significant. The aggregated overall intensity index was of limited usefulness mainly because of limitations in interpretability.
A Parable of Small Animals and Megafauna Extinction: A Paleo-Economic Theory of Climate Change versus Human Overkill in the Pleistocene
Bulte, E.H. ; Horan, R.D. ; Shogren, J.F. - \ 2006
Journal of Economic Behavior and Organization 59 (2006)3. - ISSN 0167-2681 - p. 297 - 323.
resource use - population - rationality - economics - island - exploitation - environment - fishery - models
After centuries of debate, paleontologists are converging towards the conclusion that human overkill caused the massive extinction of large mammals in the late Pleistocene. This paper revisits the question of megafauna extinction by incorporating economic behavior into the debate. We allow for endogenous human population growth, and labor allocation decisions involving activities such as wildlife harvesting and (proto) agriculture. We find that the role of agriculture in deciding the fate of megafauna was small. In contrast, the presence of ordinary small animals that have been overlooked in previous non-economic extinction models is likely to have been much more important.