Agricultural Conversion Research Articles

The Potential of Agricultural Conversion to Shape Forest Fire Regimes in Mediterranean Landscapes

In densely populated fire-prone regions, interactions between global change drivers, such as land-cover changes and climate change, may increase the frequency and severity of wildfires impacting forest ecosystems, thus diminishing their capability of provisioning key ecosystem goods and services for these societies. Yet, landscape mosaics play a crucial role in fire dynamics and behaviour. Here, we argue that promoting heterogeneous agro-forest mosaics could reduce the area affected by future fires. Specifically, we evaluated 24 landscape-scale management scenarios based on agricultural conversion, i.e. the creation of new agricultural land, that also explicitly incorporated fire suppression. Scenarios differed in the annual rate of such conversion, the spatial pattern (aggregate vs. scattered), and the location of new agricultural patches. To quantify the interactions between vegetation dynamics, fires, land-cover changes, and fire suppression, we coupled two spatially explicit models: a landscape dynamic fire-succession model and a land-cover change model. When applied to the Mediterranean region of Catalonia (NE Spain), new landscape mosaics favoured firefighting extinction capacity only after 15 years (on average) of cumulative land transformations. Agricultural conversion of at least 100 km2 year−1 was required to reduce total area burnt. A conversion rate of 200 km2 year−1 substantially improved fire suppression effectiveness, but subsequent conversion increases did not. When aggregated, new agriculture patches contributed more effectively to reduction in total area burnt and decreased the edge effect on remaining forest patches. Agricultural conversion in Mediterranean landscapes opens a new window for long-term spatial planning aimed at minimizing negative impacts of wildfire on forest ecosystems. These alternative strategies could help to develop landscape management practices in other fire-prone regions.

Effects of cropland encroachment on prairie pothole wetlands: numbers, density, size, shape, and structural connectivity

Agricultural expansion is the greatest source of wetland loss in the Prairie Pothole Region (PPR) of North and South Dakota, a critical waterfowl production area in North America. It is unknown how wetland losses from grassland conversion may alter structural connectivity in the prairie pothole network, however. We examined how agricultural expansion over the period 2001–2011 altered the number, size, shape, and structural connectivity of PPR wetlands. We hypothesized that the loss of wetlands or wetland area would decrease structural connectivity on the landscape. We analyzed a published raster database that quantified 2001–2011 agricultural conversion of wetlands in the Dakotas. A suite of structural connectivity metrics was computed using the igraph R package. Wetland area decreased by 25% within the study area, density decreased by 16%, and average size decreased from 2.41 to 2.16 ha with no increase in perimeter:area ratios, thus indicating changes more from the splitting of larger wetlands (accounting for 23% of area lost) and “nibbling” at patch area (38%) than from complete wetland elimination (39%). Despite loss of wetlands and wetland area to cropland, however, the network did not display constrained structural connectivity. Structural connectivity has not been significantly affected by wetland losses because of the large number of remaining wetlands, but wetlands will continue to be lost with ongoing grassland conversion and climate shifts. It is unknown where the tipping point of wetland losses lies in the PPR that will incur ecological costs.

Perspectives on Agricultural Land Use Conversion and Food Security in Rural Ghana

Rapid peri-urbanization has resulted in increasing demand for and pressure on peri-urban lands at the expense of agricultural lands. Households’ decision to convert from agricultural land uses to residential and commercial land uses is driven by a myriad of factors, ranging from social to economic, in the Asante-Akim South district of the Asante region, Ghana. The paper examined the effects of agricultural land use trade-off on food production in the district. Using a triangulation of qualitative and quantitative methods, 115 household respondents were proportionately sampled from three selected communities in the district, for the collection of data through the administration of questionnaires. The data were subjected to the Pearson’s chi-square, embedded in the SPSS V.16, to test for association among the variables. We report that the increasing rate of agricultural land uses conversions was as a result of increasing demand for residential and commercial land usage at the expense of agricultural land uses. Converting prime agricultural lands into other land uses was seen as profitable to agricultural expansion. A re-examination of the district land use plans by the Ghanaian Physical (Town and Country) Planning Department in tandem with the Lands Commission is therefore recommended.

Landscape-moderated biodiversity effects of ground herb cover in olive groves: Implications for regional biodiversity conservation

Studies assessing the effect of extensive versus intensive agricultural practices and addressing how biodiversity patterns and the effectiveness of agri-environmental practices (AES) to recover biodiversity are moderated by the landscape complexity (LMB framework), underlie large-scale biodiversity conservation programs and policies in anthropogenic landscapes. Such studies are numerous with annual crops and grasslands yet infrequent in more complex and structurally stable arboreal croplands, where high capacity to retain biodiversity is expected. Here, we explore to what extent landscape complexity and extensification of agricultural practices enhance biodiversity in olive groves of Andalusia (southern Spain). We monitored birds, ants and herbs in paired olive farms (extensive versus intensive ground herb cover management) from 20 localities spread over Andalusia and along a landscape complexity gradient. For each biological group, we obtained gamma diversity (diversity at the olive farm level), beta diversity (between the productive and unproductive areas located within the olive farm) and infield alpha diversity (in the productive area within the olive farm). We tested for multi-diversity, and for each group separately, three major hypotheses of the LMB: the intermediate-landscape complexity, the dominance of beta diversity, and the landscape species pool hypotheses. These hypotheses were corroborated with multi-diversity, which was affected by intensification of weed management and landscape simplification, suffering a combined impact of 26% of gamma biodiversity loss. The effectiveness of extensification to recover biodiversity depended on the landscape context and peaked at intermediate-complexity landscapes. Beta multi-diversity and infield alpha-diversity increased with landscape complexity. Birds, ants and weeds responded differently but were negatively affected either by landscape simplification or by management intensification. Birds mirrored better than other groups the multi-diversity pattern and were the best candidates for a rapid indicator of the impact of agriculture and land conversion on biodiversity. We provide recommendations for biodiversity conservation in olive groves-dominated landscapes and show that, if adequately managed, olive groves’ landscapes have potential for the conservation of biodiversity in the Mediterranean region. Our results illustrate the need to reformulate the future EU-Common Agricultural Policy and particularly, to adapt AES to each landscape.

Grass to grain: Probabilistic modeling of agricultural conversion in the North American Great Plains

Conversion of temperate grasslands in the North American Great Plains has long been identified as a threat to native species and systems. Avoiding conversion, particularly to agricultural cover, has been modeled to show benefits for preserving species diversity and connectivity and maintaining ecosystem services provided by grasslands such as avoiding nutrient and sediment runoff. To identify areas of likely conversion, we employed a probabilistic ecoregion-wide model using soil, topography, and climate variables to simulate future conversion. Our results indicated that roughly 60% of the ecoregion is at moderate or higher risk of conversion or has previously been converted. These data can be used to direct grassland conservation efforts and as a metric to assess suitability of future crop expansion. Also, with added information on government subsidies, clean energy mandates, conservation incentives, and other economic data, our model can be used to assess the benefits and disadvantages of such programs and policies.

Dynamic multi-species occupancy models reveal individualistic habitat preferences in a high-altitude grassland bird community

Moist, high-altitude grasslands of eastern South African harbour rich avian diversity and endemism. This area is also threatened by increasingly intensive agriculture and land conversion for energy production. This conflict is particularly evident at Ingula, an Important Bird and Biodiversity Area located within the least conserved high-altitude grasslands and which is also the site of a new Pumped Storage Scheme. The new management seeks to maximise biodiversity through manipulation of the key habitat variables: grass height and grass cover through burning and grazing to make habitat suitable for birds. However, different species have individual habitat preferences, which further vary through the season. We used a dynamic multi-species occupancy model to examine the seasonal occupancy dynamics of 12 common grassland bird species and their habitat preferences. We estimated monthly occupancy, colonisation and persistence in relation to grass height and grass cover throughout the summer breeding season of 2011/12. For majority of these species, at the beginning of the season occupancy increased with increasing grass height and decreased with increasing grass cover. Persistence and colonisation decreased with increasing grass height and cover. However, the 12 species varied considerably in their responses to grass height and cover. Our results suggest that management should aim to provide plots which vary in grass height and cover to maximise bird diversity. We also conclude that the decreasing occupancy with increasing grass cover and low colonisation with increasing grass height and cover is a results of little grazing on our study site. We further conclude that some of the 12 selected species are good indicators of habitat suitability more generally because they represent a range of habitat needs and are relatively easy to monitor.

Adaptive strategies of livestock waste processing technology to vulnerability availability of animal feed

The sustainability of technology processing livestock waste resulting in solid or liquid organic manure, as well as biogas has several barriers. One of them is the availability of the main raw materials such as feces and urine. The production of feces and urine depend on the quantity of the cattle and the feed capacity. Currently, it was challenging to find forage (feeding ground) due to the reduction of grassland, climate change and the conversion of agriculture land into domestic and public facilities. This study aims to identify the adaptive strategy of livestock waste technology facing the vulnerability of the livestock feed ecology. The research was conduct by qualitative approach with comparative case study design on 3 (three) farmer groups at different locations in Pinrang regency result of this research found a several adaptive strategies for the farmers such as learning technology feed, making feed fermentation (silage) and feed concentrate, livestock pasturing in the rice fields after the harvest, buying land for planting fodder forage (HMT), buying urine and feces other livestock, doing other farm coop sanitation periodically, and takes fodder forage that grew into the roads, fields, and dikes on the embankment.

Investigating the feedbacks between CO2, vegetation and the AMOC in a coupled climate model

The Atlantic Meridional Overturning Circulation (AMOC) is an important component of the climate system, however its sensitivity to the terrestrial biosphere has been largely overlooked. Here the HadCM3 coupled climate model is run for millennial timescales to investigate the feedbacks between vegetation and the AMOC at increasing CO2. The impact of agricultural conversion (termed land-use change; LUC) and the role of the simulated ‘background’ vegetation (termed land cover change; LCC) are investigated. LUC cools climate in regions of high crop fraction due to increased albedo. LCC is shown to evolve at higher CO2, with a northward migration of the tree line in the Northern Hemisphere and dieback of the Amazon. This generally acts to enhance the impact of climate change primarily due to albedo changes. Density in the Greenland-Iceland-Norwegian (GIN) Seas is crucial in driving the AMOC. Increasing CO2 decreases regional sea surface density, reducing convection and weakening the AMOC. The inclusion of LCC is shown to be responsible for a significant proportion of this weakening; reflecting the amplification effect it has on climate change. This acts to decrease the surface density in the GIN Seas. At elevated CO2 (1400 ppm) the inclusion of dynamic vegetation is shown to drive a reduction in AMOC strength from 6 to 20%. Despite the cooling effect of LUC, the impact on the AMOC is shown to be small reflecting minimal impact it has on GIN Sea density. These results indicate the importance of including dynamic vegetation in future AMOC studies using HadCM3, but LUC may be insignificant. In the context of other climate models however, the importance of vegetation is likely to be overshadowed by other systemic model biases.

Stratification of reactivity determines nitrate removal in groundwater

Biogeochemical reactions occur unevenly in space and time, but this heterogeneity is often simplified as a linear average due to sparse data, especially in subsurface environments where access is limited. For example, little is known about the spatial variability of groundwater denitrification, an important process in removing nitrate originating from agriculture and land use conversion. Information about the rate, arrangement, and extent of denitrification is needed to determine sustainable limits of human activity and to predict recovery time frames. Here, we developed and validated a method for inferring the spatial organization of sequential biogeochemical reactions in an aquifer in France. We applied it to five other aquifers in different geological settings located in the United States and compared results among 44 locations across the six aquifers to assess the generality of reactivity trends. Of the sampling locations, 79% showed pronounced increases of reactivity with depth. This suggests that previous estimates of denitrification have underestimated the capacity of deep aquifers to remove nitrate, while overestimating nitrate removal in shallow flow paths. Oxygen and nitrate reduction likely increases with depth because there is relatively little organic carbon in agricultural soils and because excess nitrate input has depleted solid phase electron donors near the surface. Our findings explain the long-standing conundrum of why apparent reaction rates of oxygen in aquifers are typically smaller than those of nitrate, which is energetically less favorable. This stratified reactivity framework is promising for mapping vertical reactivity trends in aquifers, generating new understanding of subsurface ecosystems and their capacity to remove contaminants.

Identification of hotspots of at-risk terrestrial vertebrate species in the south-central Great Plains of North America: A tool to inform and address regional-scale conservation

Biodiversity is being lost at an unprecedented rate, and resources for conservation efforts are limited. This is particularly problematic in the Great Plains of North America, where land-cover conversion for agriculture and energy production has reduced habitat for many species. In the U.S. portion of the Great Plains, a growing human population and a concomitant increasing need for food, fiber, and energy have caused landscape transformations that have resulted in over 700 vertebrate species currently being listed by state and federal conservation agencies as being at-risk in this region. Conservation efforts for such a large number of species will be most efficient when applied to areas with large numbers of these species, but such areas have never before been identified. We overlaid range maps created by the U.S. Geological Survey’s Gap Analysis Program for terrestrial vertebrate species to identify hotspots of high concentrations of U.S. state-defined Species of Greatest Conservation Need (SGCN; species that have identified as being rare or otherwise vulnerable enough to warrant conservation action in a given state) in the short- and mixed-grass prairie ecoregions of the southern and central Great Plains of the United States. We identified hotspots for species currently listed as SGCN as well as those pending designation, and a combined (current and pending) group. We then used data from the U.S. Geological Survey’s Protected Areas Database on land ownership and from the U.S. Department of Agriculture’s National Agricultural Statistics Service on land use/land cover to quantify the types of land ownership and land use/land cover types in hotspots to give land managers necessary information to address conservation of at-risk species in the Great Plains. Sufficient data were present for examination of 289 at-risk terrestrial vertebrate species. Hotspots of these species were located mostly on state- or federally-managed land in eastern New Mexico, Colorado, and west Texas. The current hottest hotspots were associated with areas with more natural/less anthropogenic forms of land use/land cover; areas with the lowest numbers of SGCNs had proportionately more cropland and less grassland than did hotspots. Identifying regional hotspots of at-risk biodiversity, and describing land use/land cover features associated with such areas, offers an opportunity to take a multi-species approach in more precisely establishing areas of conservation concern in the U.S.

Decades of native bee biodiversity surveys at Pinnacles National Park highlight the importance of monitoring natural areas over time.

Thousands of species of bees are in global decline, yet research addressing the ecology and status of these wild pollinators lags far behind work being done to address similar impacts on the managed honey bee. This knowledge gap is especially glaring in natural areas, despite knowledge that protected habitats harbor and export diverse bee communities into nearby croplands where their pollination services have been valued at over $3 billion per year. Surrounded by ranches and farmlands, Pinnacles National Park in the Inner South Coast Range of California contains intact Mediterranean chaparral shrubland. This habitat type is among the most valuable for bee biodiversity worldwide, as well as one of the most vulnerable to agricultural conversion, urbanization and climate change. Pinnacles National Park is also one of a very few locations where extensive native bee inventory efforts have been repeated over time. This park thus presents a valuable and rare opportunity to monitor long-term trends and baseline variability of native bees in natural habitats. Fifteen years after a species inventory marked Pinnacles as a biodiversity hotspot for native bees, we resurveyed these native bee communities over two flowering seasons using a systematic, plot-based design. Combining results, we report a total of 450 bee species within this 109km2 natural area of California, including 48 new species records as of 2012 and 95 species not seen since 1999. As far as we are aware, this species richness marks Pinnacles National Park as one of the most densely diverse places known for native bees. We explore patterns of bee diversity across this protected landscape, compare results to other surveyed natural areas, and highlight the need for additional repeated inventories in protected areas over time amid widespread concerns of bee declines.

Study of Agricultural Waste Processing for Different Uses (Case Study of Tea Waste)

The processing and conversion of auxiliary products, waste and agricultural waste and reuse of them in the production cycle is a suitable solution for the economic use of these types of products for medical, industrial, agricultural, or related industries. Every year, a large portion of agricultural and horticultural products in the country are lost from planting to supply to consumer markets, or during processing. It is estimated that in Iran, on average, about 100 million tons of agricultural and garden products are produced each year, of which about 20-30 percent, equivalent to 20 to 30 million tons, are waste and waste. Recycling these waste and wastes could result in the return of these materials to the economic cycle of the country. With the proper planning for the development and support of the agricultural and agricultural conversion and complementary industries, the voluminous amounts of these wastes and wastes of various stages, which have caused irreparable losses to farmers and the economy of the country, have become value added. In this article, the types of wastes of agricultural origin are studied and finally, tea waste and its applications in Iran are briefly discussed.

Protecting forests at the expense of native grasslands: Land-use policy encourages open-habitat loss in the Brazilian cerrado biome

The agricultural conversion of natural habitats is one of the main drivers of biodiversity loss worldwide. In the ∼2million km2 Brazilian cerrado biome, a global biodiversity hotspot, vast areas have been converted into croplands and cattle pastures. Because the cerrado biome is overwhelmingly contained within private lands, Brazil's environmental legislation should serve as a decisive instrument in protecting these natural ecosystems. We assessed the role of Legal Reserves (LRs), legally defined as the minimum proportion of private landholdings set aside to protect natural vegetation, in the conservation of the cerrado biome. We assume that the property-scale allocation of LRs is primarily based on economic decision-making, creating a bias against cerrado protection. We therefore assessed the area ratio between forest vegetation (FV) and grassland vegetation (GV) areas across LRs within 48,762 landholdings, 9 formal protected areas (PAs) and 34 Indigenous Lands (ILs) within the cerrado (sensu lato) of the 903,357-km2 state of Mato Grosso, Brazil. We show that there are 7.26ha of forest lands for each hectare of native grasslands within private RLs of the cerrado biome within Mato Grosso, a ratio almost three-fold larger than that found in formal PAs and ILs. ILs protect in absolute values (hectares) six-fold more native grassland vegetation than PAs. We discuss the policy relevance of this severe land-use bias in maintaining the heterogeneity of cerrado habitats for biodiversity conservation within private properties, which account for 90% of the entire cerrado biome.

A Challenge in Providing Housing Land and Sustainable Agricultural Land; An Effort to Meet The Backlog of Housing and Food Security in West Sumatra

Population growth in urban areas tends to be faster than in rural areas; it is due to various factors. Population growth has increased housing demand. The need for housing should be filled with the provision of land and houses. The most common problems in urban housing provision are less urban land available for housing and higher the price. It is happening in cities of West Sumatra, changed of agricultural land (rice field) into housing although the Government of the Republic of Indonesia has issued Act No.26 / 2007 on Spatial Planning, which sets the land allotment for spatial in Indonesia. Supporting this, in the year 2009, the Indonesian government issued, Indonesian Act No. 41/ 2009 on Sustainable Land Farming Protection, concerning on sustainable land for food agriculture, that agricultural land must be maintained in order to produce agricultural products. This paper describes to what extent of the conversion of agriculture land into housing in the last five years in several regions in West Sumatra, Indonesia. Illustrate the process of transferring land functions (from rice filed to housing), which is permitted by government regulations. This study shows that there has been a relatively significant change in the function of a rice field in urban areas. The lack of government records on land use change needs to be an important note. A legal product is governing the conversion of agricultural land, Law enforcement of spatial use rules, detailed spatial plan, reliable maps as a reference (Spatial Planning) in determining the land use of the proposed location for the house to be built, should be of particular concern by the government. It is necessary to coordinate and integrate housing and agricultural planning so that housing construction can meet the needs of the house, on the other hand, the need for rice product can be produced without having to reduce agricultural land.

Interacting effects of agriculture and landscape on breeding wader populations

The capacity of different landscapes to sustain viable populations depends on the spatial and temporal availability of key population-specific resources. Heterogeneous landscapes provide a wider range of resources and often sustain higher levels of biodiversity than homogeneous ones. Across the globe, agricultural expansion has resulted in large-scale homogenisation of landscapes with associated declines in many taxa. However, during the early stages of agricultural development, in terms of area and intensity, increased landscape heterogeneity and changes in local productivity through fertilizer inputs can potentially increase resource availability for some species. Agriculture in Iceland is currently neither highly intensive nor extensive, and primarily occurs as hayfields (>90% of agricultural land) embedded within a mosaic of semi-natural wetlands and heaths. These landscapes support internationally important breeding populations of several wader species but the role of agricultural land in promoting or constraining breeding wader densities is currently unknown. Understanding the relationship between cultivation and wader populations is important as the area of cultivated land is predicted to expand in Iceland in near future, largely through conversion of the remaining semi-natural wetlands. Here we (a) quantify relationships between breeding wader densities in lowland Iceland and the amount of cultivated land and wetland in the surrounding landscape using density estimates from 200 transects in common semi-natural habitats, (b) assess the extent to which cultivated land affects wader densities in these landscapes, and the potential effects of future agricultural expansion at the expense of wetlands on wader populations. Wader densities in semi-natural habitats were consistently greater when surrounding landscapes had more wetland at scales ranging from 500 m to 2500 m, indicating the importance of wetland availability. However, the effects of cultivated land in the surrounding landscape varied with altitude (ranging from 0 to 200 m); in low-lying coastal areas, wader numbers decline with increasing amounts of cultivated land (and the lowest densities (<1 km2) occur in areas dominated with cultivated land), the inverse occurs at higher altitudes (>100 m a.s.l., where lowest densities occur in areas without cultivated land). This suggests that additional resources provided by cultivated land may be more important in the less fertile uplands. Further agricultural conversion of wetlands in low-lying areas of Iceland is likely to be detrimental for breeding waders, but such effects may be less apparent at higher altitudes.

Monitoring and mapping rural urbanization and land use changes using Landsat data in the northeast subtropical region of Vietnam

Rapid land use change has taken place in many neighboring provinces of the capital of Vietnam such as Thai Nguyen province over the past 2 decades due to urbanization and industrialization. Deriving accurate and updated land cover and land-use change information is essential for the environmental monitoring, evaluation and management. In this study, a robust classification algorithm, Random Forest (RF) was employed in R programming to map and monitor temporal and spatial characteristics of urban expansion and land-use change in Thai Nguyen province, Vietnam. The results showed that there has been a substantial and uneven urban growth and a significant loss of forest and cropland between 2000 and 2016. Most of the conversion of agriculture and forest into built-up and mining uses were largely detected in rural regions and suburbs of Thai Nguyen. Further GIS analysis revealed that rapid urban and industrial expansion was spatially occurred in the southern rural portions and central area of the province. This study also demonstrates the potential of Landsat data and combination of R programming language and GIS to provide a timely, accurate and economical means to map and analyze temporal land cover and land use changes for future national and local land development planning.

Uncertainties in assessing the extent and legal compliance status of riparian forests in the eastern Brazilian Amazon

Riparian forests play a vital role in conserving biodiversity, maintaining ecological connectivity and assisting the delivery of key ecosystem services (i.e. maintenance of water flows). Nevertheless, riparian forests are particularly threatened across the tropics, including in Brazil following widespread forest conversion for pasturelands and agriculture. Despite the significance of the landmark Brazilian Forest Code as the basis of environmental protection on private properties, the effectiveness of the legal protection afforded to riparian vegetation in permanent preservation areas (APP, in Portuguese) has been very poorly assessed. We provide the first fine-scale estimation of the total riparian APP distribution and deficit for the 1.25 Mkm2 Brazilian state of Pará, which has the highest deforestation rate in the Brazilian Amazon in recent years, using the available properties boundaries. We demonstrate how coarse-resolution mapping data (for landscape scale mapping, e.g. 1:100,000) consistently underestimates the extent of APP areas, highlighting the scale of the challenge involved in achieving compliance with the Brazilian Forest Code. Moreover, despite nearly half (49%) of the total extent of riparian APPs being forested, following the 2012 revision of the Forest Code, the area that does not need to be restored is six times the area obligated for restoration (940,000 ha). This suggests that some catchments in Pará may not recover fully functioning hydrological and ecological services, as around 5.7 Mha of already cleared APP are likely to remain deforested because there was a law amnesty. We also found that deforestation within APPs was greater than outside APPs for most municipalities in Pará, indicating that implementation of the Forest Code has not been sufficient to protect riparian forests to date. This shortfall in the legal requirement to restore riparian forest cover suggests that under the current enforcement regime regulatory measures on their own are insufficient and incentive-based mechanisms are needed to encourage restoration – even within the existing legal framework. Our work demonstrates the importance of using finer resolution land cover data and improved hydrological models for ensuring the effective implementation of Brazilian legislation and the safeguarding of the environmental benefits provided by these critically important ecosystems.

People’s knowledge and dependency on Rampur wetland of western Chitwan, Nepal

Understanding people’s knowledge and their dependency on wetland forms the basis of conserving them. The paper assessed the status of wetland in Rampur and local peoples’ dependency on it, conducted in the year of 2013. Study revealed that majority of respondents noticed change in wetland in past years and in their priority, drying ranked first followed by decrease in acreage, and biodiversity loss. It was found that factors responsible for these changes were drought, encroachment, flooding, erosion and succession by invasive weed species. Study found that local peoples have several impacts on wetland which were conversion for agriculture, discharge of pollutants, overexploitation of aquatic resources, overgrazing conversion for residential development, and conversion for aquaculture. However, Negative impacts of wetland were flooding, foul smell, incidence of insect pest/disease, coldness in winter, and bank cutting. It was found that people dependent on wetland for farming, fodder collection, fuel wood collection, medicinal plants, religious purpose, fishery, livestock grazing, wild edible plants, irrigation, commercial fishery and recreation. Study showed that local peoples have knowledge about several aspects of wetland and they are dependent for their livelihood. Therefore, in order to protect wetland from degradation, conservation and management activities need to be implemented properly with the involvement of local peoples.

Implications of Small Population Size in a Threatened Pitviper Species

Abstract Destruction and fragmentation of wildlife habitat often results in small, isolated populations that are highly susceptible to extirpation. In many cases, however, estimates of population size are lacking, precluding accurate assessments of population viability and sound conservation management recommendations. The Eastern Massasauga (Sistrurus catenatus) is a federally threatened pitviper species that has been extirpated throughout much of its historic range attributable to agricultural conversion of wetland habitat and other synergistic threats. Population size is generally unknown among extant massasauga populations, making site-specific management difficult. In this study, we estimated genetic effective population size (Ne) and census population size (Nc) for Eastern Massasaugas at two sites in southwest Michigan. For each population, we used mark–recapture models to estimate Nc and the linkage disequilibrium method to estimate Ne. Our results revealed small Nc, with approximately 108 (95% CI ...

Increasing carbon footprint of grain crop production in the US Western Corn Belt

Global agriculture is challenged to increase soil carbon sequestration and reduce greenhouse gas emissions while providing products for an increasing population. Growing crop production could be achieved through higher yield per hectare (i.e. intensive farming) or more hectares (extensive farming), which however, have different ecological and environmental consequences. Multiple lines of evidence indicate that expanding cropland for additional production may lead to loss of vegetation and soil carbon, and threaten the survival of wildlife. New concerns about the impacts of extensive farming have been raised for the US Corn Belt, one of the world’s most productive regions, as cropland has rapidly expanded northwestward unto grasslands and wetlands in recent years. Here we used a process-based ecosystem model to distinguish and quantify how natural drivers as well as intensive and extensive farming practices have altered grain production, soil carbon storage, and agricultural carbon footprint in the US Western Corn Belt since 1980. Compared to the period 1980–2005, we found that cropland expansion more than tripled in the most recent decade (2006–2016), becoming a significant factor contributing to growing grain production. Land use change in this period led to a soil carbon loss of 90.8 ± 14.7 Tg (1 Tg = 1012 g). As a result, grain production in this region shifted from carbon neutral to a carbon loss of 2.3 kg C kg−1 grain produced. The enlarging negative carbon footprint (ΔC/ΔP) indicates the major role that cropland expansion has had on the carbon cost of grain production in this region. Therefore, we should be more cautious to pursue high crop production through agricultural cropland conversion, particularly in those carbon-rich soils.