Wood to water : short-term effects of the re-introduction of wood to streams in agricultural environments

Rehabilitation of streams on agricultural properties has become a priority for landholders and managers in recent years in Australia. Fencing and re-vegetation of riparian zones are first priorities to improve riparian habitat values and biodiversity, however changes to in-stream habitat complexity are unlikely to result in the short term. Little evidence exists to guide subsequent rehabilitation actions to address this issue. Artificially re-introducing wood to such streams may be a useful strategy to increase habitat complexity more rapidly, thereby improving in-stream biodiversity values. To test this hypothesis, as a part of the larger Productive Grazing, Healthy Rivers project, small pieces of wood were introduced to eight sites on beef and dairy properties across southern Victoria, monitoring aquatic macroinvertebrates, water quality, hydrology and habitat quality. Comparing macroinvertebrate communities before and after treatment, and between experimental and control sites, changes in community composition and colonisation are explored.

Rehabilitating agricultural streams in Australia with wood : a review

Worldwide, the ecological condition of streams and rivers has been impaired by agricultural practices such as broadscale modification of catchments, high nutrient and sediment inputs, loss of riparian vegetation, and altered hydrology. Typical responses include channel incision, excessive sedimentation, declining water quality, and loss of in-stream habitat complexity and biodiversity. We review these impacts, focusing on the potential benefits and limitations of wood reintroduction as a transitional rehabilitation technique in these agricultural landscapes using Australian examples. In streams, wood plays key roles in shaping velocity and sedimentation profiles, forming pools, and strengthening banks. In the simplified channels typical of many agricultural streams, wood provides habitat for fauna, substrate for biofilms, and refuge from predators and flow extremes, and enhances in-stream diversity of fish and macroinvertebrates.

Most previous restoration studies involving wood reintroduction have been in forested landscapes, but some results might be extrapolated to agricultural streams. In these studies, wood enhanced diversity of fish and macroinvertebrates, increased storage of organic material and sediment, and improved bed and bank stability. Failure to meet restoration objectives appeared most likely where channel incision was severe and in highly degraded environments. Methods for wood reintroduction have logistical advantages over many other restoration techniques, being relatively low cost and low maintenance. Wood reintroduction is a viable transitional restoration technique for agricultural landscapes likely to rapidly improve stream condition if sources of colonists are viable and water quality is suitable.

Does adding wood to agricultural streams enhance biodiversity? An experimental approach

Riparian clearing and the removal of wood from channels have affected many streams in agricultural landscapes. As a result, these streams often have depauperate in-stream wood loads, and therefore decreased habitat complexity and lower levels of in-stream biodiversity. The introduction of wood was investigated as a possible rehabilitation technique for agricultural streams. Wood was re-introduced to eight streams in two separate high-rainfall, intensively grazed regions of Victoria, Australia and the effect on aquatic macroinvertebrate communities was measured. The addition of wood increased overall family richness and the richness of most functional feeding groups occupying edge and benthic habitats within the stream. Wood addition led to less overlap between benthic and edge macroinvertebrate communities, suggesting increased habitat heterogeneity within the stream ecosystem. Of all sampled habitats, wood supported the greatest density of families and was colonised by all functional feeding groups. Wood habitats also had the highest overall richness and supported the most taxa that were sensitive to disturbance. These findings suggest that re-introducing wood to agricultural streams is an appropriate rehabilitation technique where those streams are affected by reduced habitat complexity. Additional work is needed to confirm these findings over larger spatial and temporal scales.

Sui generis protection for plant varieties and traditional agricultural knowledge : the example of India

Explores the sui generis protection of intellectual property, particularly patents, in biotechnology and traditional agricultural knowledge under Indian law. Focuses on the impact of amendments to the Patents Act 1970 and of the Plant Variety Protection and Farmers' Rights Act 2001 and Biological Diversity Act 2002.

Quantifying the potential impacts of increasing agricultural fragmentation on land value

Societal expectations from rural lands have traditionally focused on the production of food and fibre. Yet the perception of rural areas is changing and they are now seen in many instances to be capable of delivering multiple functions or non‐commodity outputs including land conservation and the preservation of biodiversity, contributing to the sustainable management of renewable natural resources and enhancing the socio‐economic viability of many areas . The overall multi‐functionality is constrained or favoured by biophysical and socio‐economic drivers. As these types of drivers vary spatially and temporally, so does the functionality of the landscape and heterogeneous patterns emerge. Associated with multiple functions at a single location are a variety of pressures which can manifest themselves as conflict between interacting land uses. One such conflict in rural zones is that between agricultural use and residential use. Warrnambool City Council (WCC) is a Local Government Area (LGA) in southwest Victoria where the debate surrounding the best use of rural land is currently being debated. In a region where agriculture has historically been the mainstay of the economy there is some resistance to unplanned conversion to residential use. Despite concerns and much strategy being discussed it appears an investigation quantifying the impacts of these conversions is yet to be done. This paper addresses the issue of the allocation of land by using GIS mapping to incorporate economic, social and environmental attributes, and applying a theoretical economic framework for the optimal allocation of land to the comprehensive data set. Marginal values of land for competing purposes are estimated and discussed. The method is relevant for other regions where the rural/residential interface and associated planning decisions are highly topical.

Application of a hybrid MBR system to treat herbicides from agricultural runoffs

Agricultural discharge of herbicides to the Great Barrier Reef (GBR) poses significant threat to the marine ecosystem. This study evaluates the performance of a hybrid treatment system consists of a membrane bioreactor (MBR), UV disinfection unit and a granular activated carbon (GAC) column in treating Ametryn which is one of the major herbicides in agricultural discharges. While the MBR alone removes only 40% of Ametryn at a hydraulic retention time of 7.8 hours, the hybrid system removed Ametryn to below detection levels.

Dealing with rogue virtual machines in a cloud services environment

In current cloud services hosting solutions, various mechanisms have been developed to minimize the possibility of hosting staff from breaching security. However, while functions such as replicating and moving machines are legitimate actions in clouds, we show that there are risks in administrators being able to perform them. We describe three threat scenarios related to hosting staff on the cloud architecture and indicate how an appropriate accountability architecture can mitigate these risks in the sense that the attacks can be detected and the perpetrators identified. We identify requirements and future research and development needed to protect cloud service environments from these attacks.

Ordinal Boltzmann machines for collaborative filtering

Collaborative filtering is an effective recommendation technique wherein the preference of an individual can potentially be predicted based on preferences of other members. Early algorithms often relied on the strong locality in the preference data, that is, it is enough to predict preference of a user on a particular item based on a small subset of other users with similar tastes or of other items with similar properties. More recently, dimensionality reduction techniques have proved to be equally competitive, and these are based on the co-occurrence patterns rather than locality. This paper explores and extends a probabilistic model known as Boltzmann Machine for collaborative filtering tasks. It seamlessly integrates both the similarity and cooccurrence in a principled manner. In particular, we study parameterisation options to deal with the ordinal nature of the preferences, and propose a joint modelling of both the user-based and item-based processes. Experiments on moderate and large-scale movie recommendation show that our framework rivals existing well-known methods.

Mixed-variate restricted Boltzmann machines

Modern datasets are becoming heterogeneous. To this end, we present in this paper Mixed- Variate Restricted Boltzmann Machines for simultaneously modelling variables of multiple types and modalities, including binary and continuous responses, categorical options, multicategorical choices, ordinal assessment and category-ranked preferences. Dependency among variables is modeled using latent binary variables, each of which can be interpreted as a particular hidden aspect of the data. The proposed model, similar to the standard RBMs, allows fast evaluation of the posterior for the latent variables. Hence, it is naturally suitable for many common tasks including, but not limited to, (a) as a pre-processing step to convert complex input data into a more convenient vectorial representation through the latent posteriors, thereby oering a dimensionality reduction capacity, (b) as a classier supporting binary, multiclass, multilabel, and label-ranking outputs, or a regression tool for continuous outputs and (c) as a data completion tool for multimodal and heterogeneous data. We evaluate the proposed model on a large-scale dataset using the world opinion survey results on three tasks: feature extraction and visualization, data completion and prediction.